Hypercoagulable abnormalities and postoperative failure of arterial reconstruction

Abstract

Objectives: To determine whether preoperative hypercoagulable abnormalities are independent risk-factors for the failure of arterial reconstruction in leg ischaemia.

Methods: Sixty consecutive patients were studied before, and for 1 year following, elective peripheral revascularisation. Antithrombin III, protein C and protein S levels, and tests for lupus anticoagulant were performed preoperatively, and then repeated on the first and third postoperative days and after 1 and 6 months. Heparin-associated thrombocytopenia was also investigated if there was a postoperative fall in platelet count greater than 100 x 10(9)/l.

Results: Forty-six (77%) procedures were performed for critical ischaemia and 15 (25%) involved infrapopliteal reconstruction. The nature of surgery or accepted risk factors for occlusion were comparable between the 40 (67%) patients with patent reconstructions at 1 year and the 20 (33%) who had suffered failure. Preoperative hypercoagulable abnormalities were detected in 21 (35%) patients, with a three times greater incidence in those whose reconstructions failed (65% vs. 20%, p < 0.01), and in 11 of 12 patients suffering early (within 1 month) occlusion. The lupus anticoagulant was more frequently detected when prosthetic grafts were already present (p < 0.05) and carried a positive predictive value for reocclusion of 67% (p < 0.01). All three postoperative deaths occurred in patients with low protein S levels before surgery.

Conclusions: Hypercoagulable abnormalities are common prior to arterial revascularisation and are independently associated with subsequent failure.