Catheter-directed thrombolysis for acute limb ischemia

Abstract

Acute limb ischemia is a potentially life-threatening clinical event. Thrombosis in situ, bypass graft thrombosis, and embolic occlusion are the three major precipitating events leading to acute limb ischemia. Management of acute ischemia depends on the clinical status of the affected limb and patient comorbidities. Catheter-directed thrombolysis (CDT) is the treatment of choice for patients with relatively mild acute limb ischemia (Rutherford categories I and IIa) with no contraindications to thrombolytic therapy. Patients with severe acute limb ischemia (Rutherford category IIb) need emergent revascularization. CDT should be considered, nonetheless, if the relative risks compared with primary operation are favorable. CDT is a life- and limb-saving treatment for many patients despite limitations of efficacy and associated complications. This article is a review of the etiology of acute arterial occlusion; clinical triage of patients presenting with acute limb ischemia; catheter guide wire techniques, pharmacological agents, and devices in current use for CDT; as well as the outcomes of CDT.

Keywords: Thrombolysis; acute limb ischemia; anticoagulation; plasminogen activator.

Figure 1

An elderly woman with history of atrial fibrillation presented with painful and cold left hand and absent brachial and wrist pulses. Initial angiography from a left CFA approach showed tandem emboli in the (A) proximal and (B) distal left brachial artery. Following 36-hour infusion of alteplase at 1.0 mg/h divided between a 5F multi-side hole infusion catheter and a 3F microcatheter, with heparin at 300 U/h, there was no residual embolus in the (C) left upper arm or (D) the left forearm.

Figure 2

An 80-year-old man with history of hypertension presented with a painful and cold left foot and absent popliteal and pedal pulses. (A) Initial angiography from a right CFA approach showed acute occlusion of the left superficial femoral artery. (B) After placing a 6F up-and-over sheath, a 5F multi-side hole infusion catheter was placed with the tip in the distal left popliteal artery. Alteplase (1.0 mg/h via the catheter) and heparin (200 U/h via the sheath) infusions were initiated. (C) Follow-up angiography the next day showed no residual thrombus, a high-grade stenosis at the origin of the left peroneal artery, and proximal occlusion of the left posterior and anterior tibial arteries.

Figure 3

A 67-year-old man 1 week after left popliteal artery reconstruction using autologous vein bypass graft presented with acute ischemia in the left foot and calf. The patient was referred for CDT because of risks involved in reoperation and despite warning of significant bleeding risks with CDT therapy. (A) A 5F multi-side hole catheter was placed within the graft and alteplase (0.5 mg/h via the catheter) and heparin (200 U/h via an up-and-over sheath) were initiated. (B) Follow-up angiography the next day showed a large pseudoaneurysm at the proximal anastamosis and persistent occlusion of the distal anastamosis. The patient was then taken to the operating room emergently for hematoma evacuation and graft repair.