Abstract 12656: Does Repeat Myocardial Revascularization Benefit Outcome in Asymptomatic Patients with Ischemia on Follow-Up after Previous Revascularization?

Abstract

Background. Coronary artery disease is progressive and recurring, thus stress myocardial perfusion scintigraphy (MPS) is widely used to identify ischemia in patients with prior revascularization (RVS). We sought to compare survival of patients with ischemia who underwent RVS or medical therapy (MT).

Methods. Of 6750 patients with previous RVS undergoing SPECT between January 1 2005-December 31 2007, we identified 769 patients (67.7±9.5 years, 85% men) who had ischemia and were asymptomatic. A propensity score was developed to express the associations of RVS. Patients were followed over a median of 5.7 years, Interquartile range (IQR) of [4.7-6.4 years] for all-cause death. A Cox proportional hazards model (CPH) was used to identify the association of RVS with all-cause death, with and without adjustment for the propensity score. The model was repeated in propensity-matched groups undergoing MT vs. RVS.

Results. Among 769 patients, 115 (15%) underwent RVS, after a median of 13 days (IQR [6-31 days]) after SPECT scan. There were 143 deaths; mortality of MT was 18% vs 22% RVS (p=0.84). In a CPH model (χ2=89.4) adjusting for baseline characteristics, type of prior RVS, MPS data and propensity scores, only age and hypercholesterolemia but not RVS were associated with mortality (Table). This result was confirmed in a propensity-matched group (Figure).

Conclusion. Asymptomatic patients with prior RVS and inducible ischemia realize no survival benefit from repeat RVS. In post-RVS patients, an ischemia imaging based treatment strategy did not alter outcome.