Impact of Complete Revascularization in the ISCHEMIA Trial

Abstract

BackgroundAnatomic complete revascularization (ACR) and functional complete revascularization (FCR) have been associated with reduced death and myocardial infarction (MI) in some prior studies. The impact of complete revascularization (CR) in patients undergoing an invasive (INV) compared with a conservative (CON) management strategy has not been reported. ObjectivesAmong patients with chronic coronary disease without prior coronary artery bypass grafting randomized to INV vs CON management in the ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) trial, we examined the following: 1) the outcomes of ACR and FCR compared with incomplete revascularization; and 2) the potential impact of achieving CR in all INV patients compared with CON management. MethodsACR and FCR in the INV group were assessed at an independent core laboratory. Multivariable-adjusted outcomes of CR were examined in INV patients. Inverse probability weighted modeling was then performed to estimate the treatment effect had CR been achieved in all INV patients compared with CON management. ResultsACR and FCR were achieved in 43.4% and 58.4% of 1,824 INV patients. ACR was associated with reduced 4-year rates of cardiovascular death or MI compared with incomplete revascularization. By inverse probability weighted modeling, ACR in all 2,296 INV patients compared with 2,498 CON patients was associated with a lower 4-year rate of cardiovascular death or MI (difference −3.5; 95% CI: −7.2% to 0.0%). In comparison, the event rate difference of cardiovascular death or MI for INV minus CON in the overall ISCHEMIA trial was −2.4%. Results were similar but less pronounced with FCR. ConclusionsThe outcomes of an INV strategy may be improved if CR (especially ACR) is achieved. (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches [ISCHEMIA]; NCT01471522)