PERIOPERATIVE IMAGING STRATEGIES FOR CAROTID ENDARTERECTOMY - AN ANALYSIS OF MORBIDITY AND COST-EFFECTIVENESS IN SYMPTOMATIC PATIENTS

Objective.-To assess the cost-effectiveness of four diagnostic strateg ies for the preoperative evaluation of symptomatic patients who are po tential candidates for carotid endarterectomy tie, 70% to 99% stenosis ): (1) duplex sonography (DS), (2) magnetic resonance angiography (MRA ), (3) contrast angiography (CA), and (4) the combination of DS and MR A supplemented by CA for disparate results. Methods.-Cost-effectivenes s analysis based largely on published clinical trial data, Sensitiviti es and specificities of noninvasive tests were estimated from 81 patie nts undergoing prospective evaluation with DS, MRA, and CA. Outcome Me asure.-Incremental cost per quality-adjusted year of life gained. Resu lts.-For a hypothetical cohort of symptomatic patients undergoing eval uation for carotid endarterectomy, the combination of tests resulted i n the greatest quality-adjusted life expectancy of the four options co nsidered. After incorporating the costs of testing, surgery, and strok e, we found that neither the MRA nor the CA strategy was cost-effectiv e. The combination of tests was more effective but more costly than DS , resulting in an additional cost of $22 400 per quality-adjusted year of life gained, For centers that do not have adequate MRA, CA resulte d in an additional cost of $99 200 per quality-adjusted year of life s aved compared with DS. Conclusions.-Our results suggest that for the p reoperative detection of a 70% to 99% carotid stenosis, the combinatio n of DS and MRA, supplemented by CA for disparate results, is associat ed with the lowest long-term morbidity and mortality and has a favorab le cost-effectiveness ratio. The combination of tests, or DS alone whe n MRA is not available, could potentially replace the current practice of using CA alone in the preoperative evaluation of patients with sym ptomatic carotid stenosis.