Review Question - QID 107590

This vignette describes a vasculopathic patient experiencing acute limb ischemia due to an arterial embolic occlusion. Catheter-based thrombectomy or thrombolysis will most likely improve the limb viability.

Acute arterial occlusion is caused either by embolization from a cardiac or proximal vascular site or by thrombus formation. The origin of arterial emboli is most commonly the heart (particularly in this question's patient given his atrial fibrillation). Symptoms and signs that may develop due to reduced blood supply distal to the embolism can be summarized by the 6 P's: paresthesia, pain, pallor, paralysis, poikilothermia, and pulselessness. The first-line treatment to restore circulation in mild cases is catheter-based thrombolysis, but thrombectomy using balloon-tipped Fogarty catheters is also feasible.

Sontheimer reviews peripheral vascular disease management and prevention. While this is a chronic disease, its presentation is worth comparing in the context of acute arterial occlusion. This question's patient could have been describing claudication, or exertional limb fatigue and pain. Furthermore, physical exam findings such as decreased or absent distal pulses and muscle wasting distal to the stenosed vessels can also be found. However, timing is the key dividing factor between peripheral vascular disease and acute arterial occlusion; claudication can occur multiple times depending on disease severity.

Van den Berg also reviews the literature on catheter-based thrombolysis for acute arterial occlusion compared to surgical thrombectomies. In essence, percutaneous intervention is noninferior with low complication rates. This question's patient has multiple comorbidities that increase his risk of intra- and postoperative complications, including myocardial infarction, stroke, shock, and death. A less invasive approach can mitigate these possibilities.

Incorrect Answers:
Answer 1: Percutaneous translumenal stent implantation is a possible intervention for patients with peripheral arterial disease not responding to an exercise regimen and maximal medical therapy. It is not employed in acute arterial occlusion.
Answers 2, 3, and 5: Anticoagulant agents such as heparin (and later warfarin or a novel anticoagulant such as rivaroxaban) should be provided to patients with proven acute arterial occlusion to prevent propagation of the clot and to reduce the likelihood of future embolic events. However, they do not treat the underlying occlusion.