PERIPHERAL ARTERY DISEASE (PAD)
• Prev. ↑ w/ age: <1% if <40 y, ~15% if ≥70 y; risk factors incl. smoking, DM, HTN, chol
• Claudication (dull ache, often in calves) precip by walking and relieved by stopping (vs. spinal stenosis, qv); Leriche synd = claudication, ↓ or femoral pulses, & erectile dysfxn
• Critical limb ischemia (CLI): rest pain (↑ w/ elevation b/c ↓ perfusion), ulcer (typically at pressure foci, often dry; in contrast, venous ulcers are more often at medial malleolus, wet, and with hemosiderin deposition) or gangrene, due to PAD, and >2-wk duration (implies chronicity vs. acute limb ischemia, see below)
• ↓ peripheral pulses; other signs of chronic PAD: hair loss, skin atrophy, nail hypertrophy
• Ankle:brachial index (ABI): nl 1–1.4; borderline 0.91–0.99; abnl ≤0.90; if >1.4, non-dx possibly due to calcified noncompressible vessel → ✓ PVR. If ABI abnl → segmental ABI w/ PVR to localize disease. If sx but nl ABI, ✓ for ↓ lower extrem BP after exercise.
• Duplex arterial U/S; CTA w/ distal run-off; MRA or angio
Treatment (JACC 2013;61:1555; JAMA 2013;309:453)
• Risk factor modification. Supervised exercise Rx. Screen for CAD.
• Cilostazol (if no HF) & ? ACEI to ↓ sx. ASA or clopi to ↓ D/MI/stroke if claud. or ABI <0.9.
• Revasc if CLI or limiting/refractory claudication
Acute limb ischemia (ALI)
• Sudden decrement in limb perfusion that threatens viability; viable (no immed threat of tissue loss): audible art. Doppler signals, sensory & motor OK threatened (salvage requires prompt Rx): loss of arterial Doppler signal, sensory or motor
• Etiologies: embolism > acute thrombosis (eg, athero, APLA, HITT), trauma to artery
• Clinical manifestations (6 Ps): pain (distal to proximal, ↑ in severity), poikilothermia, pallor, pulselessness, paresthesias, paralysis
• Testing: thorough pulse & neuro exam; arterial Doppler; angiography, either CT w/ bilateral run-off through feet or arteriography
• Urgent consultation w/ vascular medicine and/or vascular surgery
• Treatment: immediate anticoagulation ± intraarterial lytic; angioplasty or surgery