What do you look for in angiography for Peripheral Vascular Disease (PVD)?

What to Look for in Angiography for Peripheral Vascular Disease

When performing contrast angiography for PVD, you must obtain a complete anatomic assessment that includes the occlusive lesion itself, arterial inflow proximal to the lesion, and outflow distal to the lesion, as this comprehensive evaluation is essential for planning any revascularization strategy. 1

Primary Anatomic Targets

The diagnostic lower extremity arteriogram must image the iliac, femoral, and tibial bifurcations in profile without vessel overlap. 1 This technical requirement ensures you can accurately assess:

• Location and degree of stenosis at each arterial segment from aortoiliac vessels through tibial vessels 1
• Inflow vessels proximal to the target lesion to ensure adequate blood supply for revascularization 1
• Outflow vessels distal to the lesion to identify suitable targets for bypass anastomosis or endovascular intervention 1

Assessment of Lesion Significance

When the significance of an obstructive lesion appears ambiguous on angiography, you must obtain transstenotic pressure gradients and supplementary angulated views to definitively characterize the hemodynamic impact. 1 This is critical because:

• Visual estimation of stenosis severity can be discordant with actual hemodynamic significance 2
• Multiple viewing angles prevent misinterpretation from vessel overlap or eccentric plaque 1
• Pressure gradients provide objective hemodynamic data when anatomic severity is unclear 1

Technical Imaging Standards

Digital subtraction angiography (DSA) is the required technique because it provides enhanced imaging capabilities compared to conventional unsubtracted angiography. 1 DSA allows:

• Visualization of poorly opacified vessels 3
• Multiple viewing angles while minimizing total contrast dose 3
• Superior contrast resolution for identifying distal target vessels 4

Selective or superselective catheter placement must be performed during lower extremity angiography because this approach enhances imaging quality, reduces contrast dose, and improves both sensitivity and specificity of the procedure. 1, 5

Specific Anatomic Details to Document

You should systematically evaluate and document:

• Vessel diameter measurements at normal and stenotic segments 2
• Degree of stenosis using diameter reduction methods, recognizing that area stenosis may be underestimated by angiography alone 2
• Plaque morphology including whether lesions are concentric or eccentric, though angiography tends to overestimate concentricity compared to intravascular ultrasound 2
• Calcification patterns, acknowledging that angiography may overestimate the severity of calcification 2
• Collateral vessel pathways that may provide alternative perfusion routes 6

Critical Pitfalls to Avoid

Suboptimal angiographic technique causes significant diagnostic errors in severe PVD. 4 Common technical errors include:

• Poor collimation causing incorrect exposure and gray scale 4
• Nonselective injection resulting in inadequate vessel opacification 4
• Failure to profile lesions due to incorrect patient positioning 4
• Pseudo-occlusion from external pressure or plantar flexion 4
• Inadequate contrast volume or density, particularly in distal vessels 4

For patients with severe resting ischemia, especially those with diabetes, high-quality selective DSA is essential to ensure all distal vessels suitable for distal bypass grafting are identified. 4 Missing a patent distal target vessel can eliminate a viable revascularization option.

Pre-Procedural Requirements

Before performing angiography, you must:

• Obtain complete vascular examination and medical history to optimize access site selection and minimize contrast dose and catheter manipulation 1, 3, 5
• Document any history of contrast reactions and administer appropriate pretreatment before contrast administration 1
• Assess renal function and provide hydration for patients with baseline renal insufficiency 1
• Consider n-acetylcysteine prophylaxis for patients with creatinine >2.0 mg/dL 1, 5

Post-Procedural Monitoring

Follow-up clinical evaluation within 2 weeks after angiography is required to detect delayed adverse effects including atheroembolism, renal function deterioration, or access site complications such as pseudoaneurysm or arteriovenous fistula. 1, 5