Is thrombolysis of lower extremity acute arterial occlusion cost-effective?

The TOPAS (thrombolysis or peripheral artery surgery) trial randomized 544 patients with acute lower extremity ischemia to either surgery or thrombolysis. Although statistically equivalent 1-year morbidities and mortalities were demonstrated, the comparative cost-effectiveness of these two interventions has not been explored.

We constructed a Markov decision-analytic model to determine the cost-effectiveness of thrombolysis relative to surgery for a hypothetical cohort of patients with acute lower extremity arterial occlusion. Our measure of outcome was the cost-effectiveness ratio (CER), defined as the incremental lifetime cost per quality-adjusted life year gained. Estimates of 1-year outcomes were based on the TOPAS trial: mortality (lysis, 20%; surgery, 17%), amputation (lysis, 15%; surgery, 13%), the number of additional interventions required following the initial procedure (lysis, 544; surgery, 439). Procedural costs were estimated from the cost accounting system at the New York Presbyterian Hospital as well as from the literature.

Operative intervention for acute lower extremity arterial occlusion extended life and was less costly compared to thrombolysis. The projected life expectancy for patients who underwent initial surgery was 5.04 years versus 4.75 years for initial thrombolysis. The lifetime costs were $57,429 for surgery versus $dollar;76,326 for thrombolysis. In performing sensitivity analyses, a threshold CER of $60,000 was considered what society would pay for accepted medical interventions. Thrombolysis became cost-effective if the 1-year mortality rate for lysis was lowered from 20 to 10.7%, if the amputation rate for lysis diminished from 15 to 3.9%, or if the 1-year cost of lysis could be reduced to a level below $13,000.

Initial surgery provides the most efficient and economical utilization of resources for acute lower extremity arterial occlusion. The high cost of thrombolysis is related to the expense of the lytic agents, the need for subsequent interventions in patients treated with initial lysis, and the long-term costs of amputation in patients who fail lytic therapy.