VIRPrep — ARRT® VI Registry Exam Prep

Feature	VIRPrep	ExamEdge	Textbooks
Dedicated VI Registry questions	✓ 810	✓	—
Detailed explanations for every answer	✓	✗	—
Full study guide (all 5 areas)	✓	✗	✓
Spaced repetition algorithm	✓	✗	✗
Timed mock exam (3h 30m)	✓	✗	✗
Performance analytics dashboard	✓	✗	✗
Price	$99/year	$174 (20 tests only)	$80–120 (static)

Study Guide

All five ARRT® VI content areas — concise, clinical, exam-focused

Content Areas

22 Questions · 14% of Exam

Patient Care

Patient care is the highest-stakes section for clinical judgment. Expect questions on preprocedural assessment, contrast reactions, anticoagulation, pharmacology, and emergency management. Know the why — not just drug names and doses.

Why High-Yield

This section tests clinical decision-making in real IR scenarios. The exam loves questions where you must choose between similar drugs, recognize when a patient is deteriorating, or know which lab value to check before starting a procedure. Rote memorization fails here — pattern recognition wins.

Procedure Bleeding Risk — SIR Stratification

Risk Category (SIR 2019)	Example Procedures	INR	Platelets
Low	PICC (tip at cavoatrial junction), IVC filter placement/removal, dialysis access intervention, paracentesis, thoracentesis, superficial biopsy/aspiration, drainage catheter exchange	≤2.0–3.0	≥20,000/μL
High	TIPS, PTBD/biliary, new nephrostomy, solid-organ biopsy (liver/renal), lung biopsy, spine procedures, ablation, arterial access >7 Fr, lumbar puncture	≤1.5–1.8	≥50,000/μL

Key rule: SIR 2019 collapsed the old three-tier system into low vs high bleeding risk. Paracentesis and thoracentesis are LOW risk — routine INR correction is not required (INR up to 2.0–3.0, platelets ≥20,000/μL are acceptable). Fibrinogen >100 mg/dL applies to both categories.

Anticoagulation — Hold Times & Reversal

Hold Times (SIR 2019)

Aspirin — not held low/mod; hold 5 days high-risk
Clopidogrel — hold 5 days before high-risk procedures; per SIR 2019 it is not withheld for low-risk procedures
DOACs — hold 2–3 days (renal function dependent)
UFH (IV) — stop 4 hours before + confirm PTT/ACT normalized
LMWH (enoxaparin) — hold 24 hours before
Warfarin — hold 5 days; INR day-of

Reversal Agents

Warfarin urgent — 4F-PCC (Kcentra); FFP if PCC unavailable
Dabigatran — idarucizumab (Praxbind)
Factor Xa inhibitors — andexanet alfa (Andexxa)
UFH — protamine sulfate 1mg per 100 units UFH

Contrast Reactions — Recognition & Treatment (ACR 2023)

Severity	Key Signs	Treatment
Mild	Limited urticaria, flushing, nausea, single vomit	Observe; diphenhydramine 25–50mg PO/IM PRN
Moderate	Diffuse urticaria, mild bronchospasm, mild hypotension	O&sub2;, IV fluids; diphenhydramine IV; epi if progressing
Anaphylaxis	Bronchospasm, laryngeal edema, BP collapse, HR ↑	Epinephrine FIRST — 0.3mg IM (1:1,000) lateral thigh
Vasovagal	Hypotension + bradycardia, diaphoresis, pallor	Atropine 0.6–1mg IV; elevate legs; fluids

Critical distinction: Anaphylaxis = tachycardia. Vasovagal = bradycardia. The heart rate tells you which drug to grab first. Epinephrine for anaphylaxis. Atropine for vasovagal. The exam will flip them.

Prior reaction risk multiplier: ~5× increased risk (NOT 10×) — ACR 2024. Premedication protocol: methylprednisolone 32mg PO at 12h and 2h before contrast.

Key IR Medications — Must-Know Facts

Drug	Class/Use	Key Exam Fact
Heparin (UFH)	Anticoagulant	Reversed by protamine; monitor with aPTT or ACT
Alteplase (tPA)	Thrombolytic (CDT)	0.5–1 mg/hr intra-catheter; ABS CI: stroke <2 months
Epinephrine	Vasopressor/anaphylaxis	0.3mg IM (1:1,000) — FIRST drug in anaphylaxis
Atropine	Anticholinergic/vasovagal	0.6–1mg IV — bradycardia/vasovagal; not for anaphylaxis
Midazolam	Benzo/sedation	Reversed by flumazenil; respiratory depression risk
Fentanyl	Opioid/analgesia	Reversed by naloxone; shorter acting than morphine
Nitroglycerin	Vasodilator	100–200μg intra-arterial for vasospasm
Vasopressin	Vasoconstrictor	0.2–0.4 units/min intra-arterial for GI bleed embolization

Exam Traps — Patient Care

Trap: Paracentesis/thoracentesis require INR correction FALSE. Both are LOW bleeding risk — no routine correction needed. Low-risk thresholds still exist (INR ≤2.0–3.0, platelets ≥20,000/μL); they are simply far more permissive.
Trap: Prior contrast reaction = 10× risk FALSE. It’s ~5× (ACR 2024).
Trap: Vasovagal gets epinephrine FALSE. Vasovagal = bradycardia = atropine. Epi is for anaphylaxis (tachycardic).
Trap: UFH held 6 hours before procedure FALSE. SIR 2019 says 4 hours + confirm PTT/ACT normalized.
Trap: Warfarin reversed with FFP first FALSE. 4F-PCC (Kcentra) is preferred for urgent reversal.
Trap: Dabigatran reversed with vitamin K FALSE. Idarucizumab (Praxbind) is the specific reversal agent.

Clinical Scenarios

Scenario 1

Patient develops BP 70/40, HR 130, diffuse hives, and audible wheeze 90 seconds after contrast injection. First action?

Answer

Epinephrine 0.3mg IM (1:1,000) to lateral thigh — immediately. This is anaphylaxis. Tachycardia distinguishes it from vasovagal.

Scenario 2

INR is 1.8 day-of-procedure for a scheduled paracentesis. Procedure coordinator asks if you should delay. Your answer?

Answer

Proceed. Paracentesis is LOW bleeding risk and an INR of 1.8 sits well within the acceptable low-risk range (≤2.0–3.0 per SIR 2019). Routine correction is not required; delaying is incorrect.

Scenario 3

Patient on dabigatran needs emergent TIPS for variceal bleed. How do you reverse anticoagulation?

Answer

Idarucizumab (Praxbind) — the specific reversal agent for dabigatran. 4F-PCC is for warfarin.

Scenario 4

BP drops to 85/50, HR slows to 48, patient becomes pale and diaphoretic mid-procedure (no contrast given). What is this and how do you treat it?

Answer

Vasovagal reaction. Bradycardia is the key. Atropine 0.6–1mg IV + leg elevation + fluids. NOT epinephrine.

Preprocedure Communication & Universal Time-Out

The 3-Part Preprocedure Conversation

Explanation of procedure — reinforce what the physician explained; what patient will feel, duration, recovery
Radiation risk — explain ALARA, fluoroscopy use, skin injury risk at doses ≥5 Gy; required in consent for high-dose cases
Time-out (Universal Protocol) — entire team together, immediately before procedure

Time-Out Checklist (JC Universal Protocol)

Two patient identifiers: name + DOB or MRN
Correct procedure and site confirmed
Relevant imaging available on PACS
Correct devices/implant sizes available
Allergies confirmed, antibiotics given if indicated
All team members verbally agree — if anyone objects, procedure stops

Exam Trap: The time-out is performed by the entire team together — not the physician alone before entering the room.

Informed Consent & Emergent Consent

Type	When Used	Key Rules
Informed (written)	All elective procedures	Must be obtained before sedation; patient must understand risks, benefits, alternatives, right to refuse
Verbal	Minor additions mid-procedure	Must be documented in medical record immediately
Emergent (implied)	Incapacitated patient, life-threatening emergency	Legal presumption reasonable person would consent; document clinical status + absence of surrogate; contact family ASAP

Critical: A sedated patient cannot give new consent. Consent must be obtained before sedation begins.

Access Assessment — Allen Test & Barbeau Test

Allen Test (Radial Access Safety)

Compress both radial and ulnar arteries; patient opens/closes fist to exsanguinate
Release ulnar artery only
Normal (<7 sec): color returns → adequate ulnar collateral → radial access safe
Abnormal (>7–10 sec): inadequate collateral → radial access contraindicated

Barbeau Test (SpO&sub2; Waveform)

Type A: No change after radial compression → excellent collateral → proceed
Type B: Dampened then recovers → acceptable
Type C: Waveform lost, then recovers within 2 min → acceptable (proceed with caution)
Type D: Lost, does NOT recover → CONTRAINDICATED

NPO Status & Procedure Sequencing

Intake	Minimum Hold Before Procedure
Clear liquids	2 hours
Breast milk	4 hours
Light meal / nonhuman milk	6 hours
Full meal / fatty food	8 hours

Sequencing Rules

Nuclear scan + angiography same day → nuclear scan first (contrast reduces isotope uptake)
Biopsy + ablation same session → biopsy first, confirm diagnosis, then ablate
Metformin + contrast → hold metformin 48h only if eGFR <30 or AKI (current ACR guidance); no hold needed at eGFR ≥30 with stable renal function
Dialysis + iodinated contrast → no urgent dialysis required; do not start or reschedule dialysis solely for contrast (ACR), unless large-volume contrast or fluid-overload/cardiac concern. Gadolinium is the exception — dialysis promptly after

ECG Monitoring & Rhythm Recognition

Rhythm	Recognition	Action
Normal sinus	Regular 60–100 bpm, P before every QRS	Continue
Sinus bradycardia	Rate <60, otherwise normal	Atropine if symptomatic (BP drop, altered MS)
Sinus tachycardia	Rate >100, P waves present	Assess cause: pain, anxiety, hypovolemia, contrast reaction
PVCs	Wide bizarre QRS, no preceding P wave	Occasional = normal; frequent/multifocal → notify physician
Atrial fibrillation	Irregularly irregular, no P waves	Notify physician; rate assessment
Ventricular tachycardia	Wide QRS >100 bpm, regular	Pulseless → defibrillate; pulsatile → amiodarone
Ventricular fibrillation	Chaotic, no organized QRS	Immediate defibrillation + CPR

Capnography & Oxygen Delivery

Capnography (EtCO&sub2;)

Measures end-tidal CO&sub2; — reflects alveolar ventilation
Normal EtCO&sub2;: 35–45 mmHg
Detects respiratory depression 30–90 sec before SpO&sub2; drops
Flat waveform = apnea → stimulate, jaw thrust, reversal agents immediately
Recommended for ALL patients receiving moderate sedation

O&sub2; Delivery Devices

Nasal cannula: 1–6 L/min → 24–44% FiO&sub2; (standard for sedation)
Simple face mask: 6–10 L/min → 35–55% (min 6 L to flush CO&sub2;)
Non-rebreather: 10–15 L/min → 60–90% (significant hypoxia)
BVM: up to 100% → apnea/respiratory arrest

Exam Trap: SpO&sub2; of 97% does NOT mean breathing is adequate — capnography can show apnea while SpO&sub2; still reads normal. Flat EtCO&sub2; = act immediately.

Controlled Substance Management

DEA Schedules (IR-relevant)

Schedule II: Fentanyl, hydromorphone, morphine — highest abuse potential; two-person verification required
Schedule IV: Midazolam (Versed), lorazepam — require documentation

Wasting Protocol

Two qualified staff must be present for preparation AND waste
Witness physically observes waste — both sign the log
Waste immediately into an approved drug-deactivation/disposal system per facility and DEA policy — never saved for later (sink disposal is no longer acceptable at most institutions)
Discrepancy → immediate supervisor notification → mandatory investigation
Diversion = federal criminal offense + license revocation

Radiation Risk Communication

Tech reinforces physician's consent discussion — does not replace it
Explain: fluoroscopy uses ionizing radiation; ALARA techniques minimize dose
High-dose procedures (EVAR, TIPS, complex embolization): formal radiation risk is part of written consent
NCRP SRDL: 5 Gy cumulative air kerma — threshold for mandatory patient notification and follow-up
Young patients (especially women): higher radiosensitivity of breast, ovary, thyroid — acknowledge and explain dose reduction steps
Never say “no risk” — but contextualize: benefit typically far outweighs small statistical risk

Medical Equipment Monitoring

Equipment	Key Monitoring Points	Action if Problem
IV access	Site patency, no swelling/pain (infiltration)	Stop injection; assess; notify physician if extravasation
Drainage bags	Must stay below patient level at all times	Elevated bag → retrograde flow → infection risk
Chest tube	Output color/volume, water seal intact, no new air leak	Zero output → check for kink/obstruction; never clamp without order
Suction	Yankauer tip at bedside for all sedation cases	Verify functional before starting any sedation procedure
Oxygen	SpO&sub2; + EtCO&sub2; together; escalate O&sub2; if SpO&sub2; <92%	SpO&sub2; not improving on cannula → upgrade to non-rebreather mask

Quick Recall — Patient Care

Epinephrine 0.3mg IM (1:1,000) → anaphylaxis (tachycardic)
Atropine 0.6–1mg IV → vasovagal (bradycardic)
UFH: stop 4h + normalize PTT/ACT — NOT 6 hours
Clopidogrel: 5 days ALL procedures, no exceptions
Prior contrast reaction: ~5× risk (not 10×) — ACR 2024
Paracentesis & thoracentesis: LOW risk — no INR correction
Dabigatran reversal: idarucizumab | Factor Xa reversal: andexanet alfa
Urgent warfarin reversal: 4F-PCC first, FFP if PCC unavailable

26 Questions · 16% of Exam

Image Production

Image production tests your understanding of fluoroscopy physics, radiation safety, DSA technique, and equipment operation. The exam rewards techs who know why dose increases, not just which button to press.

Why High-Yield

This section has predictable, testable numbers (dose thresholds, scatter geometry, ALARA principles). If you know the 5 Gy Ka,r notification threshold, the 15 Gy tissue injury threshold, and the geometry of scatter radiation — you will answer most questions correctly. DSA artifact causes are also heavily tested.

Radiation Dose — NCRP Thresholds

Threshold	Value	Action Required	Source
SRDL notification	5 Gy Ka,r	Notify referring physician; follow-up at 30 & 60 days	NCRP Report 168
TJC Sentinel Event	15 Gy PSD	Report as sentinel event; skin injury likely	Joint Commission
Deterministic threshold	2 Gy PSD	Temporary erythema possible	NCRP 116
Permanent epilation	7 Gy PSD	Permanent hair loss possible	NCRP 116
Annual occupational limit	50 mSv/yr	Whole body; monitored with dosimeter	NCRP 116
Cumulative lifetime limit	10 mSv × age	Ongoing monitoring	NCRP 116

Fluoroscopy — ALARA Dose Reduction

Dose Reduction Techniques

Last image hold (LIH) — zero radiation, shows last frame
Pulsed fluoroscopy — reduces dose vs continuous
Collimation — reduces scatter and dose to patient
Maximum SID (source-to-image distance) — reduces dose
Minimum OID (object-to-image distance) — reduces magnification artifact
Remove grid for small patients — reduces dose
Low dose or pediatric mode

Dose Increase Factors

Smaller FOV (field of view) — MORE dose (AEC compensates)
Magnification mode — increases dose significantly
Steep oblique angles — increases patient dose
Continuous fluoroscopy vs pulsed
Larger patient habitus — AEC increases technique automatically
Boosted/high-dose mode

Scatter Radiation — Tube Position

X-ray Tube Position	Scatter Direction	Implication
Tube below table (PA) — standard IR setup	Backscatter directed downward (absorbed by table/floor)	Safer — keeps scatter from operator head/eyes/thyroid; table skirt shields legs
Tube above table (AP) — avoid unless required	Backscatter directed upward toward operator	More dose to operator face/eyes/thyroid; use ceiling shield + leaded glasses
LAO/RAO steep angles	Scatter toward operator side	Step back or use shield during acquisition

Rule: Backscatter is most intense on the beam-entrance side of the patient. Tube below the table (undercouch) sends backscatter downward = safer for the operator’s head/eyes/thyroid — this is why IR suites are built undercouch, with table skirts to shield the legs. Tube above the table sends backscatter upward at the operator. For lateral/oblique projections the operator closest to the tube gets the most scatter — stand on the detector side. (Separate rule, for patient skin dose: maximize source-to-skin distance and keep the patient close to the detector.)

DSA — Digital Subtraction Angiography

Issue	Cause	Fix
Misregistration artifact	Patient movement between mask and fill	Reacquire mask; breath hold coaching
Motion blur	High frame rate needed for fast vessels	Increase frames/sec (cardiac DSA)
Road mapping error	Patient moved after road map acquired	Re-acquire road map
Residual misregistration after re-mask	Small patient shift or bowel-gas movement	Pixel shifting — software re-alignment of mask to fill; reposition or re-mask if it fails

DSA principle: Mask image (no contrast) is subtracted from live image (with contrast), leaving only the vessel. Any movement between mask and fill = misregistration = artifact.

Hydrodissection — Critical Drug Safety

D5W ONLY for RFA hydrodissection. Normal saline conducts electrical current and can cause inadvertent tissue damage. This is a common safety question. D5W = electrically inert = safe to use as a thermal/electrical barrier.

Exam Traps — Image Production

Trap: Smaller FOV = less dose FALSE. Smaller FOV = MORE dose (AEC increases technique to maintain brightness).
Trap: LIH uses a small radiation burst FALSE. Last image hold = ZERO radiation. It holds the last acquired frame.
Trap: Tube above table is safer for staff FALSE. Backscatter follows the beam-entrance side: tube below the table sends it downward, away from your head — the safer, standard IR configuration. Tube above sends scatter up at your face and thyroid.
Trap: DSA misregistration is caused by contrast injection rate FALSE. Misregistration is caused by patient movement between mask and fill.
Trap: Normal saline is used for RFA hydrodissection FALSE. D5W only — NS conducts electricity.
Trap: Maximum SID increases patient dose FALSE. Maximum SID reduces dose (inverse square law).

Clinical Scenarios

Scenario 1

Cumulative fluoroscopy time reaches 85 minutes in a complex TIPS. Ka,r reads 5.2 Gy. What is your obligation?

Answer

Notify the referring physician (SRDL threshold is 5 Gy Ka,r per NCRP 168). Schedule follow-up skin assessment at 30 and 60 days.

Scenario 2

During DSA run, the subtracted image shows a ghosting artifact that looks like overlapping vessel outlines. Most likely cause?

Answer

Patient movement between mask acquisition and contrast fill = misregistration artifact. Re-acquire the mask.

Scenario 3

You switch from 9-inch to 6-inch FOV during a procedure. What happens to the patient’s radiation dose?

Answer

Dose increases. Smaller FOV triggers AEC to increase technique (kVp/mA) to maintain image brightness. Counter-intuitive but critical.

Scenario 4

Physician asks for saline to use as hydrodissection fluid during renal RFA. Your response?

Answer

Decline and provide D5W instead. Saline conducts electrical current and creates a path for thermal/electrical injury. D5W is electrically inert.

PACS — Picture Archiving & Communication System

Core Components

Acquisition interface — receives images from fluoro/DSA/CT, assigns to patient
Archive (server) — long-term storage with redundant backup
Workstations — physician/tech viewing, multiplanar reconstructions
RIS integration — links order to image; confirms patient identity before imaging
DICOM standard — universal image format; header contains patient data, dose parameters

IR Workflow

Patient registered → order placed in RIS
Workstation confirms patient identity before imaging begins
Images auto-sent to PACS after procedure
Prior imaging retrieved from PACS for intraprocedural roadmapping comparison
Physician reads from PACS; report entered in EMR

Automatic Pressure Injectors

Parameter	Typical Range	Clinical Point
Flow rate	2–25 mL/sec	Must match vessel size; too fast → dissection
Volume	5–50 mL	Enough for arterial phase; minimize contrast load
Pressure limit	Set to the catheter’s printed rating	Angiographic catheters (4–5 Fr, pigtail) are typically rated ~750–1200 PSI; PICCs/central lines are far lower at ~300–325 PSI. Always set at or below the rating on the catheter hub/package
Rise time	0.1–0.5 sec	Time to reach target flow; shorter = more abrupt

IMPORTANT: Microcatheters (2.7–2.9 Fr) have much lower pressure ratings than standard catheters. They can be power injected, but only within the manufacturer’s rated pressure and at low flow rates — never at standard large-vessel settings, which will rupture the catheter or dissect the vessel. Hand injection remains the default for superselective work. Always read the rating printed on the hub.

Air detector stops injection automatically if air detected in syringe/tubing
Flush syringe/tubing with saline before contrast to remove air
Single patient use only — never reuse syringes or tubing

Procedural Equipment — IVUS, Ablation, Thrombectomy

IVUS (Intravascular Ultrasound)

20–45 MHz catheter → 360° cross-sectional vessel image
Uses: IVC filter placement, TIPS guidance, stent apposition, dissection true/false lumen
Calcium = bright hyperechoic with posterior acoustic shadowing
Soft thrombus = low echogenicity, no shadowing

Ablation Comparison

RFA: ionic agitation → heat; grounding pads required; limited by charring; hydrodissection = D5W only
MWA: dielectric heating; no grounding pads; larger zones; not limited by charring; less heat-sink effect
Cryo: freeze-thaw ice ball; visible on CT; used near bile ducts/colon

Mechanical Thrombectomy Devices

Cryoablation (an ablation modality, listed here for comparison — not a thrombectomy device): freeze-thaw cycles; ice ball visible on CT; lethal isotherm −20°C to −40°C (several mm inside the visible 0°C ice-ball edge; probe tip ≈ −140°C); used near bile ducts/colon; less painful than RFA
Angiojet: rheolytic (Venturi effect); risk of hemolysis and bradycardia; FDA Black Box Warning — contraindicated in pulmonary arteries
Penumbra/Indigo: aspiration; continuous negative pressure
ClotTriever: large-bore mechanical removal for DVT

Intravascular Lithotripsy (Shockwave IVL)

Sonic pressure waves fracture calcified plaque without vessel injury
Balloon-based; allows subsequent DCB or stenting in calcified lesions
Available for peripheral (SFA, iliac) and coronary vessels

Radiation QC — Apron Integrity & Dose Calibration

Inspection Type	Frequency	What It Finds
Visual inspection	Each use	Visible external tears, cracks
Fluoroscopic/radiographic	At least annually	Internal lead discontinuities not visible externally

Remove from Service If:

Internal crack >1 cm in critical area (abdominal/gonadal region)
Any breach in lead lining confirmed on fluoroscopic inspection
No field repair method restores integrity — remove immediately, document in log

Storage & Calibration

Always hang on dedicated rack — never fold (creates cracks)
Annual dose calibration by qualified medical physicist
Miscalibrated unit may under-report dose — high-dose cases may have exceeded SRDL without triggering notification

Quick Recall — Image Production

5 Gy Ka,r → SRDL notification threshold (NCRP 168)
15 Gy PSD → TJC sentinel event threshold
Smaller FOV = MORE dose (AEC paradox)
LIH = ZERO radiation (holds last frame)
Tube below table (undercouch) = backscatter DOWN = safer for staff
DSA misregistration = patient movement (not injection rate)
D5W ONLY for RFA hydrodissection (not NS)
Maximum SID = less dose (inverse square law)

41 Questions · 26% of Exam

Vascular Diagnostic

The largest content area. Vascular diagnostic tests access techniques, catheter selection, anatomy, projections, and IVC anatomy for filter placement. Know your projections cold — they’re tested constantly.

Why High-Yield

26% of the exam. Master the projections (LAO 45° for aortic arch, lateral for celiac/SMA, LAO 15–30° for the renal ostia — not the old ipsilateral-oblique rule), know the Seldinger technique cold, and understand IVC anatomy variants. Femoral access details and catheter selection are tested heavily.

Vascular Access — Femoral Technique

Femoral Artery Access

Target: common femoral artery over the medial femoral head
Femoral head = backstop for compression post-procedure
Too high (above inguinal lig.) → retroperitoneal hematoma
Too low (below bifurcation) → pseudoaneurysm, AV fistula
Fluoroscopic landmark: inferior border of femoral head
Seldinger: needle → wire → dilator → sheath

Access Complications

Hematoma — most common complication
Pseudoaneurysm — pulsatile mass, visible on US
AV fistula — continuous bruit, venous pulsations
Retroperitoneal bleed — high stick, flank pain, ↓Hgb
Arterial dissection — resistance to wire
Vasovagal — bradycardia + hypotension post-procedure

Key Projections — Must Memorize

Vessel/Study	Best Projection	Why
Aortic arch	LAO 45°	Opens arch, shows origins of great vessels
Celiac axis	Lateral	Shows origin off aorta without overlap
SMA	Lateral	Same as celiac — both arise from the anterior aortic wall
Right renal artery	LAO 15–30°	Right renal ostium arises ~20–30° ventrally; an anterior oblique swings it off the aortic silhouette
Left renal artery	LAO ~10°	Measured angles average +21° (right) and +9° (left), positive = LAO; an empiric 10–20° LAO opens both ostia in ~75% of patients
Carotid bifurcation	Ipsilateral oblique (~30–45°), lateral if needed	Separates ICA from ECA; the working angle is chosen per side and per patient
Renal hilum	Ipsilateral posterior oblique	Shows bifurcation pattern
Adrenal vein sampling	Right = technically difficult	Short right adrenal vein drains directly to IVC. Selectivity index: adrenal vein cortisol ≥3× peripheral IVC (basal) confirms cannulation. Lateralization ratio >4:1 = unilateral adenoma → adrenalectomy.

IVC Anatomy Variants — Critical for Filter Placement

Variant	Prevalence	Impact on Filter Placement
Duplicated IVC	0.2–3%	Bilateral iliac filters OR suprarenal single filter
Circumaortic left renal vein	2.4–8.7% (~4%)	Must image both limbs; filter above highest LRV
Retroaortic left renal vein	~2–3%	Filter below LRV insertion to avoid thrombosis
Left-sided IVC	0.2–0.5%	Crosses midline; access may require repositioning

Cavagram rule: Mandatory before EVERY IVC filter placement regardless of prior imaging. Anatomy can change. Thrombus may extend higher than expected.

Standard filter position: Infrarenal IVC just below the lowest renal vein. Suprarenal placement only when infrarenal is not possible (e.g., thrombus up to renals, pregnancy, duplicated IVC).

Catheter Selection

Catheter	Shape/Use	Key Application
Cobra (C2)	Simple curve	Celiac, SMA, renal arteries from femoral
Simmons (SIM)	Reverse curve	Difficult arch anatomy; subclavian, carotid from femoral
Headhunter (H1)	Angled tip	Great vessel selection from femoral approach
Pigtail	Curled tip, multiple side holes	Aortogram, ventriculogram (high flow)
Bernstein	Slight angle	Selective vessel catheterization, brachial approach
Kumpe	Angled tip	Selective catheterization, drainage

Exam Traps — Vascular Diagnostic

Trap: Celiac/SMA best seen in AP FALSE. Lateral projection shows celiac and SMA origin off the anterior aorta.
Trap: Duplicated IVC is common (>5%) FALSE. Prevalence is only 0.2–3%. Circumaortic LRV is the more common variant at 2.4–8.7%.
Trap: Cavagram can be skipped if recent CT shows normal IVC FALSE. Mandatory before every filter placement.
Trap: Right adrenal vein sampling is straightforward FALSE. It’s technically difficult due to the short right adrenal vein draining directly to the IVC.
Trap: Femoral head is a landmark for arterial compression, not needle entry FALSE. The femoral head is the backstop for BOTH needle entry and post-procedural compression.
Trap: LAO 45° is used for renal arteries FALSE. LAO 45° = aortic arch. Renal arteries are opened with a shallow LAO (10–30°), not a 45° arch obliquity — and not the old “ipsilateral oblique” rule, which measured CT/MR angles have displaced.

Clinical Scenarios

Scenario 1

Cavagram before IVC filter placement shows two IVC channels from L4 to the confluence. What are your filter options?

Answer

Duplicated IVC (<1% prevalence). Options: bilateral common iliac filters OR single suprarenal filter above the duplication.

Scenario 2

Physician asks for best projection to visualize the celiac axis takeoff during an aortogram. What do you set up?

Answer

Lateral projection. The celiac and SMA originate from the anterior aorta — lateral view shows these origins without vessel overlap.

Scenario 3

Post-femoral arterial puncture, patient has a pulsatile groin mass with a bruit. What complication and what diagnostic test?

Answer

Pseudoaneurysm. Diagnose with duplex ultrasound. Treat with ultrasound-guided compression or thrombin injection.

Scenario 4

During right renal arteriogram, the origin of the right renal artery is not well visualized in AP. What projection do you try?

Answer

A shallow LAO (about 15–30°). The right renal artery arises roughly 20–30° ventrally from the aorta, so a left anterior oblique brings the ostium into profile. An empiric 10–20° LAO opens both renal ostia in about 75% of patients.

Central Venous Device Check

Performed for malfunctioning central venous devices: no blood return, poor flow, difficult infusion.

Finding	Fluoroscopic Appearance	Management
Fibrin sheath	Contrast outlines outside of catheter and flows back up tract	Alteplase (tPA) dwell: 2 mg in 2 mL, 30–120 min, then aspirate
Tip malposition	Tip in IJ, axillary, or azygos vein — not in SVC	Reposition over guidewire
Intraluminal thrombus	Filling defect within catheter lumen	tPA dwell; consider exchange if failed
Catheter fracture	Contrast leak at fracture site	Remove catheter; foreign body retrieval if fragment embolized
Pinch-off syndrome	Catheter kinked at costoclavicular space	Remove before complete fracture and embolization

Ideal Catheter Tip Positions

PICC/Port: lower SVC or SVC–RA junction
Too high (above right clavicle): malposition → reposition
Right atrium: arrhythmia risk → pull back
Right ventricle: urgent repositioning — perforation risk

Port Access

Access only with non-coring Huber needle (right-angle bent tip)
Resistance + pain at port site → stop; assess for needle malposition before any injection
Ports sustain 1,000–3,500+ access cycles depending on model

Lymphangiography

Indications

Chylous leak (chylothorax, chylous ascites) — pre-thoracic duct embolization mapping
Chylothorax clue: milky pleural fluid, triglycerides >110 mg/dL

Technique & Key Facts

Contrast: Lipiodol (ethiodized oil) — oil-based; persists in nodes for months
Intranodal approach (preferred): ultrasound-guided direct inguinal node puncture
Cisterna chyli: L1–L2; thoracic duct drains to left subclavian–jugular junction
Thoracic duct embolization (TDE): coils ± NBCA; ~70–80% success

Exam Trap: Lipiodol is oil-based — NOT standard iodinated aqueous contrast. Do not confuse them.

Vascular Anatomy — Aorta & Celiac Territory

Abdominal Aortic Branches (T12–L5)

Branch	Level
Celiac trunk	T12–L1
Superior mesenteric artery (SMA)	L1
Renal arteries (bilateral)	L1–L2
Inferior mesenteric artery (IMA)	L3
Aortic bifurcation → common iliac	L4

Celiac Trunk Trifurcation

Left gastric artery — smallest; supplies lesser curvature of stomach
Splenic artery — largest and most tortuous; runs along superior pancreatic border
Common hepatic artery — gives off GDA then becomes proper hepatic artery → divides into right and left hepatic arteries
Classic trifurcation present in ~89% of individuals

Exam Trap: The gastroduodenal artery (GDA) passes POSTERIOR to the first part of the duodenum. Posterior duodenal ulcers erode the GDA — the classical cause of massive upper GI hemorrhage treated by GDA coil embolization.

Hepatic Arterial Variants — Michels Classification

Hepatic arterial anatomy is highly variable. Every patient undergoing TACE or hepatic embolization requires complete mapping before treatment.

Variant	Prevalence	Clinical Impact
Replaced RHA from SMA	10–15%	Most common variant — absent right hepatic on celiac arteriogram → catheterize SMA
Replaced LHA from left gastric	~10%	Second most common — runs in lesser omentum → superselect left gastric
Accessory RHA from SMA	~7%	Additional right hepatic supply alongside normal RHA — both must be embolized
Michels Type IX (replaced CHA from SMA)	Rare	Entire liver supplied by SMA — no hepatic branches visible on celiac arteriogram
Normal (Type I)	~55%	Celiac gives off all three vessels; standard hepatic supply

Critical: Before any hepatic embolization — perform celiac arteriogram FIRST, then SMA arteriogram to identify replaced/accessory hepatic vessels. Missing a replaced hepatic artery = incomplete treatment or non-target embolization.

IVC Anatomy & Variants — Critical for Filter Placement

Normal IVC Anatomy

Forms at L4–L5 from junction of common iliac veins
Ascends on the RIGHT side of aorta
Receives renal veins at L1–L2, hepatic veins at T8–T9
Passes through caval hiatus of diaphragm at T8
Standard filter placement: infrarenal (below renal veins)

IVC Variants — Alter Filter Strategy

Duplicated IVC (0.2–3%) — bilateral infrarenal filters OR suprarenal filter above confluence
Left-sided IVC (0.2–0.5%) — joins left renal vein → crosses anterior to aorta; filter in left-sided IVC via left femoral access
Circumaortic LRV (2.4–8.7%) — two left renal veins encircle aorta; retro-aortic limb may be lower — may need suprarenal filter
Retro-aortic LRV (~3%) — single left renal vein crosses posterior to aorta

Cavogram Tip: Duplicated IVC suspected when left common iliac vein inflow defect is absent on right femoral cavogram and infrarenal IVC appears smaller than expected.

Portal Venous System & Mesenteric Collaterals

Portal System Formation

Portal vein = SMV + splenic vein, posterior to pancreatic neck at L1–L2
IMV drains into splenic vein (NOT directly into portal confluence)
Portal vein ascends in hepatoduodenal ligament with hepatic artery (left) and bile duct (right)
Divides at porta hepatis into right and left portal veins

Key Mesenteric Collaterals

Arc of Riolan — middle colic (SMA) → left colic (IMA); central mesentery; prominent in SMA/IMA occlusion
Marginal artery of Drummond — runs along inner colon margin; connects SMA and IMA territories
Pancreaticoduodenal arcade — connects celiac and SMA; preserved if either is occluded

Renal & Adrenal Venous Anatomy

Structure	Left Side	Right Side
Renal vein length	Longer — crosses anterior to aorta	Short — drains directly into IVC
Tributaries	Left gonadal + left adrenal + left phrenic	None — right gonadal and adrenal drain directly into IVC
Adrenal vein	Drains into left renal vein	Drains directly into right IVC posterolateral wall (3–5mm) — most challenging AVS catheterization
Gonadal vein	Left gonadal → left renal vein (varicocele/PCS embolization via left renal vein)	Right gonadal → directly into IVC

Nutcracker Syndrome: Left renal vein compressed between abdominal aorta and SMA → left renal venous hypertension → hematuria, left flank pain, left varicocele/pelvic congestion. Treatment: LRV stenting or transposition.

Cerebrovascular Anatomy — Arch to Circle of Willis

Aortic Arch Branches (Proximal to Distal)

Brachiocephalic (innominate) trunk — divides into right common carotid + right subclavian
Left common carotid artery
Left subclavian artery

Left vertebral artery arises directly from arch in ~6% (between left CCA and left subclavian).

Circle of Willis Connections

AComm (anterior communicating) — bridges L and R anterior circulations (ACAs) — most common aneurysm site (30–35%)
PComm (posterior communicating) — bridges ICA to PCA bilaterally
Vertebral arteries arise from subclavian arteries → unite at pontomedullary junction → basilar artery → bilateral PCAs
Left vertebral dominant ~45%; right dominant ~30%; co-dominant ~25%

CCA Bifurcation (Key for Carotid Stenting)

Bifurcates at C3–C4 (upper thyroid cartilage level)
ICA — larger, posterior/lateral; NO branches in the neck
ECA — smaller, anterior/medial; multiple neck branches
Carotid body (chemoreceptor) + carotid sinus (baroreceptor) at bifurcation

ARRT Exam Focus

Aortic arch anatomy required for catheter selection in neuro cases
Bovine arch (common origin CCA + brachiocephalic) — ~7% of population
Vertebral artery anomalies affect access for vertebral angiography
Know Mani vs Simmons catheter for difficult aortic arch configurations

Peripheral Arterial Anatomy — Lower Extremity Runoff

Vessel	Location / Course	Key Clinical Point
Common femoral artery (CFA)	Overlies medial third of femoral head	Standard access site; target puncture over femoral head for hemostasis
Profunda femoris	Arises from CFA 3–5cm below inguinal ligament	Collateral source in SFA occlusion; not a target for angioplasty
Superficial femoral artery (SFA)	Passes through adductor (Hunter's) canal	Most common site of PAD; transitions to popliteal at adductor hiatus
Popliteal artery	Posterior to knee in popliteal fossa	Divides at lower popliteal fossa into AT and tibioperoneal trunk
Anterior tibial artery	Passes through interosseous membrane anteriorly	Continues as dorsalis pedis at foot
Tibioperoneal trunk	Short segment after AT takeoff	Divides into posterior tibial (medial) and peroneal (lateral/fibular)
Posterior tibial artery	Medial calf behind medial malleolus	Supplies plantar foot; palpable posterior to medial malleolus
Peroneal artery	Lateral compartment alongside fibula	Often last patent vessel in critical limb ischemia — may be only outflow

Pelvic Projections: 25° RAO profiles the LEFT internal iliac system; 25° LAO profiles the RIGHT — counterintuitive but high-yield ARRT question.

Quick Recall — Vascular Diagnostic

Aortic arch → LAO 45°
Celiac & SMA → Lateral
Right renal → LPO | Left renal → RPO
Femoral head = backstop for compression AND needle entry landmark
Cavagram mandatory before EVERY IVC filter (no exceptions)
Duplicated IVC <1% → bilateral iliac filters or suprarenal
Circumaortic LRV 3–4% | Retroaortic LRV 2–3%
Right adrenal vein = technically difficult (short, directly to IVC)

41 Questions · 26% of Exam

Vascular Interventional

The most procedure-heavy section. TIPS, IVC filters, embolization, CDT, Y-90, and ablation. Know your PSG targets, embolization agent properties, and CDT contraindications cold.

Why High-Yield

This section rewards techs who understand procedure rationale, not just steps. Know why TIPS targets PSG <12 mmHg, why Gelfoam is temporary, why D5W is used for RFA, and why MWA has no heat-sink effect. These are the distinctions that separate passing from failing.

TIPS — Transjugular Intrahepatic Portosystemic Shunt

Parameter	Value	Notes
PSG target (all indications)	<12 mmHg	AASLD 2021; applies to varices AND refractory ascites
Optimal PSG	<8–10 mmHg	Better variceal bleed control
Standard stent	VIATORR (ePTFE-covered)	Reduces pseudointimal hyperplasia vs bare metal
Most common delayed complication	Hepatic encephalopathy	25–35% of patients; ammonia elevation
Access vein	Right hepatic vein → right portal vein	Most common approach
Absolute CI	Severe right heart failure, polycystic liver, uncontrolled sepsis	Relative CI: moderate encephalopathy

PSG math: During TIPS the gradient is measured directly: portal vein pressure − right atrial (or IVC/free hepatic vein) pressure. Do not subtract the wedged hepatic pressure — wedging estimates portal pressure itself, so that would give roughly zero. The indirect equivalent used at transjugular biopsy is HVPG = wedged HVP − free HVP. A gradient ≥12 mmHg before TIPS means varices are likely to re-bleed; the goal after TIPS is <12 mmHg.

Embolization Agents — Properties

Agent	Duration	Primary Use	Key Fact
Gelfoam	Temporary (days–weeks)	Trauma, GI bleed, post-partum hemorrhage	Resorbs; vessel recanalizes
Coils	Permanent	Aneurysms, AVMs, vessel occlusion	Mechanical occlusion; platinum or stainless
PVA particles	Permanent	UAE (500–900 μm), tumor embolization	Size selection determines level of occlusion; 500–900 µm matched to uterine artery caliber
CO₂ contrast	—	Contrast allergy, renal insufficiency (below diaphragm)	Absolutely contraindicated above diaphragm (cerebral, coronary, pulmonary). No nephrotoxicity.
Embospheres	Permanent	UAE, HCC, tumor	Calibrated microspheres; more uniform than PVA
Onyx (EVOH)	Permanent	AVM, aneurysm	Liquid agent; requires DMSO-compatible microcatheter
n-BCA glue	Permanent	Rapid hemorrhage, AVF	Polymerizes on contact with blood; fast set
Ethanol (EtOH)	Permanent	Renal ablation, AVM sclerosis	Cytotoxic; extreme pain — general anesthesia

CDT — Catheter-Directed Thrombolysis

CDT Protocol

Drug: alteplase (tPA) — 0.5–1 mg/hr intra-catheter
Concurrent UFH: 300–500 units/hr (systemic anticoagulation)
Check fibrinogen q8h — stop if <150 mg/dL
Neurological checks q1h during infusion
Post-CDT: angioplasty/stent for underlying stenosis

CDT Contraindications

Absolute: Active intracranial hemorrhage
Absolute: Stroke <2 months (ischemic OR hemorrhagic)
Absolute: Active internal bleeding
Absolute: Recent (<2 months) intracranial/spinal surgery
Relative: Recent surgery <10 days, pregnancy, severe hypertension

Y-90 Radioembolization

Parameter	Value/Details
Isotope	Yttrium-90 (Y-90) — pure beta emitter
Pre-procedure imaging	Tc-99m MAA scan (mandatory) — assesses lung shunt fraction
Lung shunt CI	>20% lung shunt fraction = contraindication
GI shunting concern	Aberrant vessels to bowel = risk of radiation gastroenteritis
Main indication	Unresectable HCC, colorectal liver mets
Post-embolization syndrome	Fever, nausea, fatigue — expected; manage supportively

Tc-99m MAA rule: Always required before Y-90. If lung shunt >20%, do NOT proceed. No exceptions.

Ablation — RFA vs MWA

Feature	RFA (Radiofrequency)	MWA (Microwave)
Mechanism	Ionic agitation → heat	Water molecule oscillation → heat
Heat-sink effect	Yes — vessels >3mm reduce ablation zone	No — not limited by adjacent vessels
Hydrodissection fluid	D5W ONLY (electrically inert)	D5W preferred but less critical
Speed	Slower	Faster (higher temps achieved)
Tumors near vessels	Suboptimal (heat-sink)	Preferred

Exam Traps — Vascular Interventional

Trap: TIPS PSG target is <8 mmHg PARTIAL. <12 mmHg is the standard target per AASLD 2021 for ALL indications. Optimal is <8–10 mmHg but <12 is what’s tested.
Trap: Gelfoam is a permanent embolic agent FALSE. Gelfoam is temporary; recanalizes within days to weeks.
Trap: MWA has a heat-sink effect near vessels FALSE. MWA is NOT affected by heat-sink. RFA is.
Trap: CDT with tPA is safe 3 months post-stroke FALSE. Stroke <2 months is an absolute contraindication.
Trap: Y-90 Tc-99m MAA scan is optional if CT looks clean FALSE. Mandatory. Lung shunt fraction >20% = absolute contraindication.
Trap: TIPS encephalopathy rate is <10% FALSE. 25–35% of patients develop hepatic encephalopathy post-TIPS.

Clinical Scenarios

Scenario 1

Post-TIPS, the directly measured portal pressure is 18 mmHg and the right atrial pressure is 9 mmHg. Is the procedure successful?

Answer

PSG = portal − right atrial = 18 − 9 = 9 mmHg. Yes — below the <12 mmHg AASLD target, so the shunt is hemodynamically successful. (Note the gradient is taken against right atrial/IVC pressure, not against a wedged pressure.)

Scenario 2

Pre-Y-90 Tc-99m MAA scan shows 22% lung shunt fraction. What do you do?

Answer

Do NOT proceed. Lung shunt >20% is an absolute contraindication to Y-90 radioembolization. Radiation pneumonitis risk is too high.

Scenario 3

During RFA of a 3.5cm renal tumor adjacent to the renal vein, ablation zones are consistently smaller than expected. Why?

Answer

Heat-sink effect. The adjacent large vessel (renal vein) dissipates heat, reducing the effective ablation zone. Consider MWA instead.

Scenario 4

Patient had ischemic stroke 6 weeks ago and now has acute iliofemoral DVT with phlegmasia. Can you perform CDT?

Answer

No. Stroke <2 months is an absolute contraindication to CDT. The risk of intracranial hemorrhage is too high.

Atherectomy — Four Types

Type	Device Example	Mechanism	Key Fact
Directional	SilverHawk, TurboHawk	Rotating cutter shaves plaque; collected in nosecone for removal	Debris removed from body in nosecone
Rotational	Rotablator	Diamond burr at high speed; microparticles <7μm pass distally	Debris embolizes distally into the microcirculation; particles are small enough to traverse capillaries and be cleared by the reticuloendothelial system
Orbital	Diamondback 360	Eccentric diamond crown; larger zone at higher speed	Bidirectional; one crown size treats multiple vessel diameters
Laser (Excimer)	Turbo-Elite	308 nm UV photons break molecular bonds (no heat)	CTO, in-stent restenosis, thrombus

Exam Trap: Rotational atherectomy debris goes distally (small enough to cross the capillary bed rather than being retrieved). Directional atherectomy debris is collected in the nosecone and removed. This distinction is tested.

No-reflow after rotational atherectomy: treat with intracoronary vasodilators (adenosine, nitroprusside, or verapamil) — NOT stenting.

Endograft Placement — EVAR & TEVAR

EVAR (Abdominal)

Indications: AAA ≥5.5 cm (men), ≥5.0 cm (women), or rapidly enlarging (>0.5 cm/6 mo)
Requires: infrarenal neck ≥10–15 mm, angulation <60°, iliac access ≥7 mm
Post-EVAR follow-up: CTA at 1 month, 12 months, then annually

TEVAR (Thoracic)

Indications: descending TAA ≥5.5–6 cm, traumatic transection (zone 3–4), complicated type B dissection
Spinal cord ischemia = most feared complication — coverage of T8–L2 intercostals
Prevention: CSF drainage + maintain MAP >80–85 mmHg

Endoleak Types

Type	Source	Management
Type I	Seal failure at landing zone (Ia proximal, Ib distal)	Urgent repair — highest rupture risk
Type II	Branch vessels (IMA, lumbar) filling sac retrogradely	Observe if sac stable; embolize if sac grows
Type III	Graft defect or junction separation	Urgent repair
Type IV	Graft porosity (rare with modern grafts)	Usually self-limited

Transvenous (Transjugular) Liver Biopsy

Indications (vs. Percutaneous)

Coagulopathy (INR >1.5–2.0) — bleeding tracks into hepatic vein, not peritoneum
Tense ascites — avoids hepatic capsule traversal
Thrombocytopenia (platelets <50,000)
Simultaneous HVPG measurement desired

HVPG Measurement

HVPG = Wedged HVP − Free HVP
Normal: 1–5 mmHg
>10 mmHg = clinically significant portal HTN
>12 mmHg = variceal hemorrhage risk
TIPS target: <12 mmHg (AASLD 2021)

Complication to know: Hemobilia — hepatic artery to biliary fistula → Quincke’s triad: RUQ pain + jaundice + GI bleeding (delayed 1–5 days). Treatment: hepatic artery embolization.

Adequate biopsy: minimum 6 portal tracts; 11 recommended for reliable fibrosis staging.

Distal Protection Devices

Type	Mechanism	Examples
Filter wire	Micropore basket captures debris distal to lesion; retrieved after stent	SpiderFX, Emboshield NAV6, FilterWire EZ
Proximal occlusion	Balloons in ECA + CCA create no-flow field; debris aspirated before restoring flow	Mo.Ma Ultra

Mandatory for carotid artery stenting (CAS) — Class I recommendation. Filter deployed in disease-free distal ICA; retrieved with dedicated catheter after stent + post-dilation. This is a tested ARRT topic.

Foreign Body Retrieval

Common Foreign Bodies

Fractured guidewires (most common)
Broken port catheter fragments (pinch-off syndrome)
Embolized IVC filter struts
Misdeployed coils

Retrieval Devices

Gooseneck snare (Amplatz): most common; 90° loop lassoes object
En Snare: three-loop design for irregular objects
Alligator forceps: jaw-style grasper for right heart objects

Critical technique: Object is snared and pulled INTO a large sheath before extraction — never pulled directly through vessel wall. Sheath must accommodate the object.

Pinch-off syndrome: port catheter compressed between clavicle and 1st rib → fracture → fragment lodges in RV or PA. Recognized by >90° catheter angle at costoclavicular space on fluoroscopy.

Hybrid OR — Interventional Suite vs. Hybrid Operating Room

Feature	IR Suite	Hybrid OR
Imaging	Fixed angiography system	Same + CBCT, fusion imaging capability
Surgical capability	Minor open access only	Full open surgery: anesthesia boom, surgical lighting, instrument tables
Team	IR tech, interventionalist, RN	All of above + surgeon, anesthesiologist, scrub tech
Key advantage	—	In-room surgical conversion without patient transport
Room size	~480–600 sq ft	~750–1,100 sq ft

Why it matters on the exam: EVAR/TEVAR failure → immediate surgical conversion in same room. Fixed flat-panel detectors → superior image quality at lower dose vs. mobile C-arm. Added to ARRT spec in 2022 update.

Procedural Anatomy — Key Relationships for Interventions

Uterine Artery Embolization (UAE)

Uterine artery — first major branch of anterior division of internal iliac
Crosses superior to the ureter (“water under the bridge”)
Ovarian artery arises directly from aorta — separate supply to uterine fundus
Non-target embolization of ovarian artery → premature ovarian failure

Artery of Adamkiewicz — TEVAR Risk

Dominant anterior spinal artery feeder to thoracolumbar cord
Arises from left intercostal/lumbar artery between T8–L1 in ~75%
Left-sided in ~80% of individuals
TEVAR coverage of this level → spinal cord ischemia (paraplegia)
Prevention: CSF drainage + MAP >80–85 mmHg

Hepatic Dome HCC Parasitic Supply

Right inferior phrenic artery (IPA) — most common extrahepatic feeder for HCC in segments VII/VIII (hepatic dome)
Occurs in ~10–15% of HCC cases — must catheterize separately for complete TACE
Other feeders: intercostal arteries, right internal mammary, omental vessels

TIPS Anatomy

Access via right hepatic vein (most common) from right IJV
Needle directed anteriorly, inferiorly, medially toward right portal vein
HVPG measured: WHVP − FHVP
Normal HVPG: 1–5 mmHg; >10 = clinically significant PHT; >12 = variceal risk
TIPS target: <12 mmHg (AASLD 2021)

Quick Recall — Vascular Interventional

TIPS PSG target: <12 mmHg (AASLD 2021) — ALL indications
TIPS most common delayed complication: hepatic encephalopathy (25–35%)
Gelfoam = temporary | Coils/PVA/Onyx = permanent
CDT alteplase dose: 0.5–1 mg/hr intra-catheter
CDT absolute CI: stroke <2 months
Y-90 pre-procedure: Tc-99m MAA mandatory — lung shunt >20% = stop
RFA: heat-sink effect near vessels | MWA: no heat-sink
D5W ONLY for RFA hydrodissection — never NS

30 Questions · 19% of Exam

Nonvascular

Nonvascular covers the breadth of IR: nephrostomy, biliary drainage, biopsy, spine procedures, and drainage. Know your access points, cement properties, and why urosepsis is the most dangerous nonvascular complication.

Why High-Yield

The exam tests nephrostomy access anatomy (posterior lower pole calyx), biliary drainage hierarchy, vertebroplasty vs kyphoplasty distinctions, and complication management. Biopsy needle types and yield are also frequently tested. Urosepsis as the #1 life-threatening nonvascular complication appears on almost every exam.

Percutaneous Nephrostomy — Access Anatomy

Optimal Access

Target: posterior lower pole calyx
Approach: Brödel’s avascular line (lateral avascular plane)
Posterior calyces point posterolaterally → most accessible
Needle passes through renal parenchyma into collecting system
Fluoroscopy + ultrasound guidance for initial access

Upper Pole Risks

Upper pole access → risk of pneumothorax (above 12th rib)
Also: pleural effusion, hydrothorax
Avoid if possible; use subcostal approach
If upper pole required: expiration approach, confirm with CXR post-procedure

Complication	Type	Notes
Urosepsis	Most dangerous	Can be fatal; antibiotics BEFORE procedure mandatory
Perinephric hematoma	Most common	Usually self-limiting; watch Hgb
Pneumothorax	Upper pole access	CXR after any above-12th-rib access
Injury to adjacent organs	Colon, spleen	Pre-procedure CT to assess anatomy

Biliary Drainage — PTC & PTBD

Procedure Hierarchy

PTC (cholangiogram) — diagnostic only; delineates biliary anatomy
PTBD (biliary drain) — therapeutic; external or internal-external
External drain — above obstruction only; bile drains to bag
Internal-external — crosses obstruction; bile into duodenum + bag
Fully internalized (stent) — no external drain; bile drains internally only

Key Safety Rules

Antibiotics BEFORE biliary procedure — infected bile = immediate sepsis risk
Right-sided access: 10th–11th intercostal space at or just anterior to the midaxillary line — below the 10th rib, because the pleural reflection reaches the 10th rib here and a higher stick is transpleural (pneumothorax, biliary pleural effusion, empyema)
Left-sided access: subxiphoid/epigastric approach
Cholangiography: contrast fills system; identify level of obstruction

Vertebroplasty vs Kyphoplasty

Feature	Vertebroplasty	Kyphoplasty
Mechanism	PMMA cement injected directly into fracture	Balloon tamp inserted first → cavity created → cement
Height restoration	Minimal to none	Possible (balloon expands before cement)
Cement volume	Higher (no cavity)	Lower (fills cavity)
Cement leak risk	Higher	Lower (cavity contains cement)
Cost	Lower	Higher
Indication	Painful osteoporotic VCF, myeloma	Same; preferred when height restoration desired

Critical safety rule: Cement leak into the epidural space → STOP injection immediately + neurological check. Epidural cement = potential cord compression.

PMMA (polymethylmethacrylate) = bone cement used in both procedures. Viscosity matters: too thin → leaks; too thick → won’t flow.

Biopsy — Needles & Yield

Type	Needle	Sample	Best For
Fine needle aspiration (FNA)	20–25G cutting/aspiration	Cytology (cells)	Thyroid, lymph nodes, cysts
Core needle biopsy	14–18G spring-loaded	Histology (tissue architecture)	Liver, lung, renal, soft tissue
Coaxial technique	Introducer + inner needle	Multiple samples, one pass	Reduces tract seeding risk
Vacuum-assisted	8–11G rotational	Larger samples	Breast, bone marrow

Lung biopsy specific: Most common complication = pneumothorax. Occurs in 20–35% but only ~5% require chest tube. High bleeding risk per SIR 2019 (INR ≤1.5–1.8, platelets ≥50,000/μL).

Exam Traps — Nonvascular

Trap: Upper pole nephrostomy is the preferred access FALSE. Posterior lower pole calyx is standard. Upper pole = pneumothorax risk.
Trap: Kyphoplasty always restores vertebral height FALSE. Height restoration is possible, not guaranteed. Depends on fracture acuity.
Trap: Vertebroplasty has lower cement leak risk than kyphoplasty FALSE. Vertebroplasty injects directly — higher leak risk. Kyphoplasty fills a pre-formed cavity.
Trap: Perinephric hematoma is the most dangerous nephrostomy complication FALSE. Most common yes, but most dangerous = urosepsis (can be fatal).
Trap: Biliary procedures don’t require pre-procedure antibiotics if patient is afebrile FALSE. All biliary procedures require antibiotics BEFORE starting, regardless of fever status.
Trap: FNA provides tissue architecture for histology FALSE. FNA = cytology only. Core needle biopsy = histology (tissue architecture).

Clinical Scenarios

Scenario 1

During PTBD, patient becomes febrile and hypotensive immediately after bile is aspirated. What is happening and what do you do?

Answer

Urosepsis/biliary sepsis from infected bile entry into bloodstream. Broad-spectrum antibiotics immediately, IV fluids, blood cultures, and expedite drainage. This is life-threatening.

Scenario 2

During kyphoplasty cement injection, the patient reports sudden new back pain. Fluoroscopy shows cement tracking toward the posterior cortex. What do you do?

Answer

Stop injection immediately. Assess for epidural leak. Neurological check. Epidural cement can cause cord compression — this is a surgical emergency if neurological deficits develop.

Scenario 3

Nephrolithiasis patient needs nephrostomy drainage above the 11th rib due to anatomy. Post-procedure, patient is dyspneic. First test?

Answer

Chest X-ray to rule out pneumothorax. Upper pole/intercostal access carries risk of pneumothorax. May require chest tube if large.

Scenario 4

Pathology requests tissue architecture for suspected hepatocellular carcinoma. Which biopsy needle type do you use?

Answer

Core needle biopsy (14–18G spring-loaded). FNA provides cytology only — insufficient for tissue architecture/histology required for HCC diagnosis.

Suprapubic Catheter Placement

Indications: urinary retention not amenable to urethral catheterization (stricture, trauma, false passage); long-term bladder drainage
Critical requirement: bladder must be adequately distended (>300 mL) — confirmed by ultrasound before puncture
Access: midline suprapubic, 2–3 cm above pubic symphysis; ultrasound + fluoroscopy guidance
Confirm with contrast injection — fills bladder lumen, no perivesical extravasation
First exchange: wait 2–4 weeks for tract maturation; routine exchange every 4–8 weeks

Antegrade Urography & Whitaker Test

Antegrade Urography

Contrast injected through existing nephrostomy tube
Assesses: collecting system, ureteral obstruction location, stricture, leak, passage to bladder

Whitaker Test (Pressure-Perfusion)

Differentiates obstructed vs. non-obstructed dilated system
Saline perfused at 10 mL/min; renal pelvis pressure measured simultaneously
Normal: <15 cmH&sub2;O
Obstructed: >22 cmH&sub2;O
Equivocal: 15–22 cmH&sub2;O

Enteric Tube Evaluation (G-tube / GJ-tube Verification)

Inject water-soluble contrast (Gastrografin / diatrizoate — NOT barium) through tube under fluoroscopy
Contrast fills stomach = G-tube correct; passes to jejunum = GJ-tube correct
Extravasation into peritoneum = tube dislodged → STOP feeds immediately
Barium is contraindicated — peritoneal barium causes chemical peritonitis

Cholecystostomy

Indications

Acute cholecystitis in patients too high-risk for surgery (elderly, critically ill)
Acalculous cholecystitis in ICU patients
Bridge to surgical cholecystectomy

Technique

Transhepatic approach preferred — liver provides tamponade layer, reduces bile leak vs. transperitoneal
Ultrasound guidance; locking drainage catheter placed into gallbladder
Confirm with contrast injection — fills gallbladder, no extravasation
Catheter matured 4–6 weeks before cystogram or stone extraction

Exam Trap: Preferred access is transhepatic, not transperitoneal. The liver acts as a tamponade reducing bile leak risk.

Tunneled Drainage Catheters (PleurX)

PleurX (Tunneled Pleural)

Indication: recurrent malignant or refractory pleural effusion
15.5 Fr catheter tunneled from pleural entry to skin exit site
Drained at home via vacuum bottles 3×/week
Spontaneous pleurodesis in ~40–50% of malignant cases
Proprietary one-way valve — requires specific drainage kit; standard syringes cannot connect

Peritoneal Tunneled Drain

Indication: recurrent malignant ascites
Same tunneling technique as PleurX
Allows outpatient drainage without repeated paracentesis

Lumbar Puncture & Myelogram

Lumbar Puncture

Entry level: L3–L4 or L4–L5 (below conus medullaris at L1–L2)
Preferred needle: 22–25G pencil-point (Sprotte or Whitacre) → reduces post-LP headache
Normal opening pressure: 7–18 cmH&sub2;O (lateral decubitus)
Post-LP headache (10–30%): supine, fluids, caffeine; blood patch if severe

Myelogram — Critical Safety

Contrast: Iohexol (Omnipaque) ONLY — nonionic water-soluble, intrathecally approved
NEVER: ionic contrast (seizures), gadolinium (not standard of care), barium (absolute CI)
Post-procedure: keep patient upright 30–45° for 4–6 hours
Post-myelogram CT within 60 minutes

Epidural Steroid Injection (ESI)

Approach	Best For	Notes
Transforaminal (TFESI)	Unilateral radiculopathy; targeted	Most common in IR; “Scotty dog” oblique view; inject to safe triangle
Interlaminar (ILESI)	Central/bilateral symptoms	Broad spread; between laminae
Caudal	L5–S1 predominant; prior surgery	Via sacral hiatus

CRITICAL SAFETY RULE: For cervical transforaminal ESI — use dexamethasone ONLY (non-particulate). Triamcinolone or methylprednisolone (particulate steroids) can embolize to the vertebral or anterior spinal artery → cord infarction / stroke. This is a high-stakes ARRT exam topic.

Paracentesis — SIR Risk & Albumin Replacement

SIR Bleeding Risk Classification

Paracentesis = LOW risk — same as thoracentesis
No specific INR or platelet correction threshold required
Coagulation parameters do not reliably predict bleeding for low-risk procedures

Albumin Replacement (LVP >5 L)

Prevents paracentesis-induced circulatory dysfunction (PICD)
IV albumin: 6–8 g per liter removed, given after procedure
Normal saline is NOT an acceptable substitute
Volumes <5 L: albumin not required

Exam Trap: Candidates assume coagulopathy requires correction before paracentesis — SIR guidance does NOT support routine correction for this LOW-risk procedure.

Procedural Anatomy — Nonvascular Access

Nephrostomy Access Anatomy

Target: posterior lower pole calyx via posterolateral approach
Access through posterior axillary line — avoids descending colon anteriorly
Needle directed in axis of infundibulum toward calyx
Upper pole access reserved for ureteropelvic junction obstruction or complex stone work
Collecting system accessed under fluoroscopic + ultrasound guidance

Biliary Anatomy

Right + Left hepatic ducts → common hepatic duct at porta hepatis
Cystic duct joins CHD → forms common bile duct (CBD)
CBD descends in hepatoduodenal ligament (with portal vein posterior, hepatic artery left)
CBD traverses pancreatic head → drains at ampulla of Vater into D2
PTC/PTBD: right or left intrahepatic approach targeting peripheral ducts

Lumbar Puncture Layers (L3–L4 or L4–L5)

Skin → subcutaneous fat
Supraspinous ligament
Interspinous ligament
Ligamentum flavum (“pop” felt here)
Epidural space
Dura mater → arachnoid → subarachnoid space (CSF)

Vertebroplasty Access

Transpedicular approach — needle through pedicle into posterior vertebral body
Critical boundary: medial pedicle wall must not be violated → spinal canal
Lateral wall violation → pneumothorax (thoracic) or retroperitoneal injury (lumbar)
Cement must NOT cross posterior vertebral cortex

Quick Recall — Nonvascular

Nephrostomy access: posterior lower pole calyx via Brödel’s line
Upper pole access → pneumothorax risk (post-CXR mandatory)
Most dangerous nephrostomy complication: urosepsis (can be fatal)
Most common nephrostomy complication: perinephric hematoma
Biliary procedure: antibiotics BEFORE, no exceptions
Kyphoplasty: balloon first → cavity → cement (possible height restoration)
Vertebroplasty: direct cement injection (more leak risk)
Cement epidural leak → stop immediately + neuro check
Core needle = histology | FNA = cytology only

Test	Normal	Threshold & Use
INR	0.8–1.2	<2.0 low-risk / <1.5 moderate & high-risk (SIR)
aPTT	25–35 sec	50–100 sec = therapeutic IV UFH
ACT	70–120 sec	>200 sec = procedural anticoagulation (tableside)
Platelets	150–400 K/µL	>50,000 required for all IR procedures
Creatinine	0.6–1.2 mg/dL	Elevated → eGFR → CIN risk assessment
eGFR	>60 mL/min	<30 = high CIN risk → IOCM or CO₂
K⁺	3.5–5.0 mEq/L	Correct if abnormal — arrhythmia risk with sedation

Drug	Use & Dose	Reversal
Heparin (UFH)	Procedural anticoag. ACT monitoring.	Protamine 1mg per 100U UFH
Alteplase (tPA)	CDT 0.5–1mg/hr via catheter	FFP/cryoprecipitate (no specific reversal)
Fentanyl	Opioid — 100× potency of morphine	Naloxone 0.4–2mg IV
Midazolam (Versed)	Benzo — anxiolysis/amnesia	Flumazenil 0.2mg IV (max 1mg)
Epinephrine	Anaphylaxis — 0.3mg IM (1:1,000)	N/A
Atropine	Vasovagal bradycardia — 0.5–1mg IV	N/A
Nitroglycerin	Arterial spasm — 100–200mcg IA	N/A
Methylprednisolone	Contrast premedication — 32mg PO ×2	N/A

Parameter	Limit
Occupational whole body (annual)	50 mSv/year (5 rem)
Occupational lens of eye	150 mSv/year
Occupational extremity	500 mSv/year
Declared pregnancy (total)	5 mSv entire pregnancy
Patient reporting threshold	≥5 Gy cumulative air kerma
DAP units	mGy·cm²
TLD advantage	Can be re-read; accurate integrated dose

Procedure	Access	Technical Goal	Key Complication
TIPS	Right IJV → hepatic vein → portal vein (transhepatic)	PSG <12 mmHg	Hepatic encephalopathy (25–35%)
IVC Filter	Right femoral or IJV. Infrarenal below lowest renal vein.	PE prevention (cavagram first)	Filter fracture, IVC thrombosis, perforation
Nephrostomy	Posterior lower pole calyx. Prone. US + fluoro.	Decompress obstructed system	Hemorrhage (most common), urosepsis
Biliary Drain (PTCD)	Transhepatic right lobe. Prophylactic Abx mandatory.	Decompress obstructed bile duct	Biliary sepsis (most dangerous)
Vertebroplasty	Transpedicular under fluoroscopy	Pain relief in VCF	PMMA cement leak → epidural or PE
TACE	CFA → hepatic artery → tumor feeder	Tumor devascularization + local chemo	Post-embolization syndrome (expected)
Y-90	CFA → hepatic artery (after MAA shunt study)	Radiation delivery to tumor	Radiation pneumonitis if shunt >20%
Carotid Stenting (CAS)	CFA → aorta → carotid with distal EPD	Stent across stenosis with EPD deployed	Stroke/TIA from distal embolization
Tunneled HD Catheter	Right IJV preferred. Subcutaneous tunnel.	Tip at SVC-RA junction	Fibrin sheath, infection, thrombosis
Percutaneous Gastrostomy	Air insufflation + T-fastener gastropexy	Secure tube through gastropexied stomach	Peritonitis (pneumoperitoneum >48h)

Structure	Origin / Level	Key Clinical Fact
Celiac trunk	Anterior aorta at T12–L1	Trifurcation: left gastric + splenic + common hepatic (~89%)
Replaced RHA	From SMA (10–15%)	Most common hepatic variant — must identify before TACE
Replaced LHA	From left gastric (~10%)	Second most common — runs in lesser omentum
Michels Type IX	Entire hepatic supply from SMA	No hepatic branches on celiac arteriogram — check SMA
SMA origin	Anterior aorta at L1	Passes anterior to D3 (duodenum); arc of Riolan = SMA–IMA collateral
IVC formation	L4–L5 confluence of common iliac veins	Ascends RIGHT of aorta; passes through T8 caval hiatus
Duplicated IVC	Prevalence 0.2–3%	Bilateral filters OR suprarenal filter required
Left-sided IVC	Prevalence 0.2–0.5%	Joins left renal vein → crosses anterior to aorta → right suprarenal IVC
Circumaortic LRV	Prevalence 2.4–8.7%	Two left renal veins encircle aorta — alters filter placement zone
Portal vein	SMV + splenic vein posterior to pancreatic neck at L1–L2	IMV drains into splenic vein (not portal confluence directly)
Left renal vein	Crosses anterior to aorta	Receives left gonadal + left adrenal + left phrenic veins
Right adrenal vein	3–5mm — drains directly into IVC	Most challenging AVS catheterization; right IVC posterolateral wall
Aortic arch branches	Proximal to distal	1. Brachiocephalic → 2. Left CCA → 3. Left subclavian
Vertebral arteries	From subclavian arteries bilaterally	Unite at pontomedullary junction → basilar artery; left dominant ~45%
CCA bifurcation	C3–C4 (upper thyroid cartilage)	ICA = posterior/lateral; ECA = anterior/medial; carotid body here
Anterior communicating artery	Between bilateral ACAs	Most common intracranial aneurysm site (~30–35%)
SFA → popliteal transition	Adductor (Hunter's) canal → adductor hiatus	Common SFA occlusion site due to repetitive flexion stress
Popliteal trifurcation	Lower popliteal fossa / proximal fibular head	AT → anterior; Tibioperoneal trunk → PT + peroneal
Uterine artery	Anterior division of internal iliac	'Water under bridge' — crosses superior to ureter
Artery of Adamkiewicz	Left T8–L1 intercostal/lumbar (75%)	Dominant anterior spinal feeder — TEVAR coverage → spinal ischemia
Right IPA	Right inferior phrenic artery	Most common extrahepatic HCC feeder (hepatic dome, seg VII/VIII)
Internal iliac projections	25° RAO → left IIA in profile; 25° LAO → right IIA in profile	Counterintuitive — contralateral oblique profiles each IIA

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Lab Values & Procedural Thresholds

Contrast Reactions — ACR 2023 Treatment

Medications & Reversal Agents

Radiation Protection — NCRP Limits

Key Procedures — Access, Goals & Complications

Vascular Anatomy — Key Facts & Variants

Patient Prep — NPO, Consent & Monitoring

Severity	Key Signs	Treatment
Mild	Limited urticaria, flushing, nausea	Observe. Diphenhydramine 25–50mg PRN.
Moderate	Diffuse urticaria, mild bronchospasm	O₂, IV fluids, Benadryl 50mg IV. Epi IM if progressing.
Anaphylaxis	Bronchospasm, collapse, tachycardia	Epinephrine FIRST: 0.3mg IM (1:1,000) or 0.1mg IV (1:10,000)
Vasovagal	Bradycardia + hypotension	Legs up, fluids, O₂, Atropine 0.5–1mg IV. NOT epi.
CIN	Cr ↑ ≥0.3mg/dL in 48h	Pre-hydration NS, minimize contrast, IOCM, hold metformin

Topic	Key Rule	Source
NPO — Clear liquids	2 hours minimum before procedure	ASA guidelines
NPO — Light meal	6 hours minimum	ASA guidelines
NPO — Full meal	8 hours minimum	ASA guidelines
Informed consent	Must be obtained BEFORE sedation; covers risks, benefits, alternatives, right to refuse	JCAHO
Emergent (implied) consent	Incapacitated patient + life-threatening emergency; document absence of surrogate	Legal standard
Universal time-out	Entire team together, immediately before procedure; patient ID + procedure + site confirmed	JC Universal Protocol
Allen test normal	Color returns to palm within 7 seconds after releasing ulnar artery	Standard technique
Barbeau Type D	SpO₂ waveform lost and does NOT recover → radial access CONTRAINDICATED	Barbeau 2001
EtCO₂ normal	35–45 mmHg; flat waveform = apnea (detects 30–90s before SpO₂ drops)	AANA standards
Controlled substance waste	Two qualified staff witness AND sign; physical waste immediately; no saving	DEA 21 CFR
Lead apron inspection	Visual each use; fluoroscopic/radiographic annually; never fold — always hang	NCRP / facility policy
Metformin + contrast	Hold 48h after contrast only if eGFR <30 or AKI; no hold needed at eGFR ≥30. Resume when renal function confirmed stable	ACR guidelines (current)

Pass the VI Registry.The first time.

Everything you need. Nothing you don't.

Built to the exact ARRT® blueprint.

The honest comparison.

One price. Everything included.

Frequently asked questions.

Lab Values & Procedural Thresholds

Contrast Reactions — ACR 2023 Treatment

Medications & Reversal Agents

Radiation Protection — NCRP Limits

Key Procedures — Access, Goals & Complications

Vascular Anatomy — Key Facts & Variants

Patient Prep — NPO, Consent & Monitoring

Pass the VI Registry.
The first time.