Arterial · IR Playbook

Diagnostic Lower-Limb Angiography (DSA LL)

Diagnostic lower-limb angiography is catheter-based digital subtraction angiography used to define arterial inflow, femoropopliteal disease, infrapopliteal runoff and pedal circulation. It is primarily performed when non-invasive imaging is inconclusive, when precise anatomical characterization is required or immediately before a planned endovascular intervention. Complete angiography should demonstrate the arterial tree from the infrarenal aorta or iliac inflow through the pedal vessels while minimizing contrast volume, radiation exposure and access-site complications.

Learning objectives

• Select appropriate indications for catheter angiography after reviewing duplex ultrasound, CT angiography or MR angiography.
• Choose between retrograde common femoral, contralateral crossover, ipsilateral antegrade, radial and alternative arterial access.
• Perform systematic inflow, outflow, tibial runoff and pedal-arch angiography.
• Recognize stenoses, occlusions, collateral pathways, distal targets and angiographic signs of acute limb ischemia.
• Prevent and manage access-site, thromboembolic and contrast-related complications.

Indications

• Chronic limb-threatening ischemia with rest pain, non-healing ulcer or gangrene when detailed arterial mapping is required for revascularization planning.
• Lifestyle-limiting claudication being considered for endovascular or surgical revascularization.
• Acute limb ischemia requiring rapid anatomical definition and possible immediate endovascular treatment.
• Inconclusive, discordant or technically limited duplex ultrasound, CT angiography or MR angiography.
• Severe arterial calcification, metallic hardware or other factors limiting non-invasive angiography.
• Evaluation of arterial trauma, pseudoaneurysm, arteriovenous fistula, embolic disease, vasculitis or other non-atherosclerotic arterial disorders.
• Preoperative mapping of inflow, runoff and potential distal bypass targets.
• Assessment of suspected restenosis, occlusion or other complication following previous endovascular or surgical revascularization.

Relative contraindications

• Uncorrected clinically significant coagulopathy or severe thrombocytopenia.
• Active bleeding or inability to obtain safe arterial access and postprocedural haemostasis.
• Previous severe immediate hypersensitivity reaction to iodinated contrast without an acceptable alternative or premedication plan.
• Acute kidney injury or severe chronic kidney disease when the expected diagnostic benefit does not outweigh contrast-associated risk.
• Uncontrolled hypertension, decompensated heart failure or severe cardiopulmonary instability.
• Local infection over the intended access site.
• Pregnancy unless the procedure is urgent and expected to alter management.
• Patient refusal or inability to cooperate when appropriate anaesthetic support is unavailable.

Equipment

• Ultrasound machine with high-frequency linear transducer and sterile probe cover
• Micropuncture access set with 21 G needle, 0.018-inch guidewire and 4 to 5 Fr introducer
• 18 G arterial access needle and 0.035-inch J-tip guidewire when standard access is used
• 4 or 5 Fr vascular sheath, typically 10 to 25 cm depending on access and anatomy
• 4 or 5 Fr pigtail or multiside-hole flush catheter for infrarenal aortography and bilateral runoff
• 4 or 5 Fr angled diagnostic catheter such as Cobra, Simmons, RIM, Omni Flush or internal mammary configuration for iliac selection
• 0.035-inch hydrophilic angled guidewire, typically 150 to 260 cm
• 0.035-inch stiff or exchange-length guidewire when stable crossover access is required
• Non-ionic low-osmolar or iso-osmolar iodinated contrast medium
• Power injector with pressure-limited tubing and manifold
• Heparinized saline flush according to institutional protocol
• Digital subtraction angiography system with bolus-chase, road-map and last-image-hold capability
• Manual compression materials and an appropriately sized vascular closure device when indicated

Procedure steps

1. Review symptoms, examination findings, kidney function and prior imaging. Decide the required proximal starting level, laterality, access route and whether immediate intervention is possible.Pearl: In chronic limb-threatening ischemia, plan the pedal acquisitions before starting so the study does not end with an incomplete tibial runoff.
2. Place the patient supine with both groins and the selected alternative access site prepared when necessary. Position both legs straight and minimize external rotation to reduce subtraction and anatomic distortion.Pearl: Immobilize the feet gently before bolus-chase acquisition because distal motion is a common cause of nondiagnostic pedal images.
3. Identify the common femoral artery, bifurcation, calcification and adjacent vein using ultrasound. Puncture the anterior wall over the femoral head and introduce a 4 or 5 Fr sheath using micropuncture or standard Seldinger technique.Pearl: Save an ultrasound image documenting needle entry into the artery.
4. Inject a small contrast volume through the sheath in an ipsilateral oblique projection when the puncture level is uncertain or a closure device is planned. Confirm entry into the common femoral artery without dissection, severe stenosis or puncture near the bifurcation.
5. Advance a flush catheter over a guidewire into the infrarenal aorta, keeping the catheter below the renal arteries unless more proximal imaging is required. Perform an anteroposterior aortogram, with oblique pelvic views when iliac stenosis, overlap or bifurcation disease requires clarification.Pearl: Typical adult aortography uses approximately 15 to 25 mL at 10 to 15 mL per second, but volume and rate must be tailored to catheter position, vessel size, cardiac output and equipment.
6. For contralateral evaluation, engage the common iliac artery with a flush or shaped catheter and pass a hydrophilic wire into the external iliac or common femoral artery. Advance the catheter across the bifurcation over the wire without forcing resistance.Pearl: Secure catheter position in the distal external iliac artery or common femoral artery for selective runoff while avoiding obstruction of a critically stenosed inflow vessel.
7. Acquire anteroposterior images from the common femoral artery through the superficial and profunda femoris arteries. Use ipsilateral oblique projections to separate the superficial and profunda origins and to profile eccentric stenoses.Pearl: Always include the profunda femoris because it is an important collateral and potential surgical inflow or outflow vessel.
8. Continue imaging through the superficial femoral artery, adductor canal and popliteal artery. Acquire additional oblique or flexed-knee views when overlap, calcification or a suspected focal lesion prevents accurate assessment.
9. Image the popliteal trifurcation, anterior tibial artery, tibioperoneal trunk, posterior tibial artery and peroneal artery through the ankle. Use selective injections, lower injection rates and delayed acquisitions when proximal occlusion or slow flow limits distal opacification.Pearl: Selectively positioning the catheter closer to the knee can markedly improve tibial visualization while reducing contrast volume.
10. Obtain dedicated magnified foot images demonstrating the dorsalis pedis, medial and lateral plantar arteries, deep plantar connection and pedal arch. Tailor projections and timing to the ulcer location and suspected target arterial path.Pearl: For tissue loss, document whether continuous in-line flow reaches the foot and whether the artery supplying the wound-related angiosome is patent.
11. Use orthogonal projections, magnification, road mapping or selective catheterization to characterize ambiguous stenoses, occlusion caps, collateral origins, bypass grafts or suspected aneurysms. Record lesion length and identify proximal and distal reference vessels.Pearl: When treatment is contemplated, image beyond the lesion sufficiently to identify safe landing zones, distal targets and collateral branches.
12. Review the final images and distal limb perfusion before removing the catheter and sheath. Obtain haemostasis with manual compression or an appropriate closure device, then confirm the access-site appearance and distal pulses or Doppler signals.Pearl: Document distal pulses immediately before and after sheath removal.

Complications

• Access-site hematoma or bleeding, approximately 1 to 3 percent
• Femoral pseudoaneurysm, approximately 0.2 to 2 percent
• Arteriovenous fistula, generally below 1 percent
• Arterial dissection, thrombosis or distal embolization, generally below 1 percent
• Contrast-associated acute kidney injury, incidence variable and increased in high-risk patients
• Acute iodinated contrast reaction, allergic-like reactions approximately 0.6 percent and severe reactions approximately 0.04 percent
• Access-site infection, below 1 percent

Exam pearls

• The ideal common femoral puncture is over the femoral head, below the inguinal ligament and above the femoral bifurcation.
• A high femoral puncture risks retroperitoneal hemorrhage; a low puncture risks pseudoaneurysm and arteriovenous fistula.
• Complete chronic limb-threatening ischemia angiography must include dedicated ankle and foot images.
• Never label a distal artery occluded without delayed imaging when proximal disease or slow flow is present.
• The profunda femoris is a major collateral pathway and must be included in femoral angiography.
• Carbon dioxide is useful below the diaphragm but is generally inferior to iodinated contrast for tibial and pedal vessels.

Viva questions

What is the preferred femoral puncture site for lower-limb angiography?

The preferred site is the common femoral artery over the femoral head, below the inguinal ligament and above the origins of the superficial and profunda femoris arteries. This location permits effective compression and reduces retroperitoneal bleeding and low-puncture complications.

Why should the foot be imaged in chronic limb-threatening ischemia?

Foot imaging demonstrates the dorsalis pedis, plantar arteries, pedal arch and the artery supplying the wound-related angiosome. This information is essential for selecting a target arterial path and confirming whether in-line flow can be restored to the foot.

What are the advantages and limitations of bolus-chase angiography?

Bolus-chase angiography rapidly surveys both lower limbs with one proximal injection. Its limitations include motion and misregistration artifacts, unequal flow between limbs and inadequate depiction of slow-flow tibial and pedal vessels.

How do you differentiate true distal occlusion from slow flow?

Obtain delayed acquisitions and a selective injection closer to the suspected lesion after confirming adequate proximal inflow. Collateral reconstitution and late distal opacification indicate delayed flow rather than absence of a patent distal vessel.

What is the role of carbon dioxide angiography?

Carbon dioxide can reduce iodinated contrast exposure in selected patients with kidney dysfunction or iodinated contrast hypersensitivity. It performs best in larger vessels below the diaphragm, provides poorer distal runoff images and must not be injected into arterial territories above the diaphragm.

What information should be reported for an arterial occlusion?

Report the arterial segment, occlusion length, proximal cap morphology, calcification, collateral pathways, distal reconstitution, number and quality of runoff vessels and the condition of the pedal circulation.

What is the most dangerous consequence of a high common femoral puncture?

A high puncture above the inguinal ligament can cause non-compressible retroperitoneal hemorrhage. It may present with hypotension, tachycardia, falling haemoglobin and abdominal, flank or back pain.

What should you do if the distal pulse disappears after angiography?

Immediately reassess the limb and perform targeted angiography or duplex ultrasound to identify thrombosis, dissection or embolization. Maintain wire access when possible and initiate urgent endovascular or surgical rescue according to limb viability.

References