Implications of the ISCHEMIA trial on the practice of surgical myocardial revascularization

Coronary artery bypass grafting versus medical therapy in patients with stable coronary artery disease: An individual patient data pooled meta-analysis of randomized trials

OBJECTIVES

It is unclear whether coronary artery bypass grafting (CABG) improves survival compared with medical therapy (MT) in patients with stable coronary artery disease (CAD). The aim of this analysis was to perform an individual-patient data-pooled meta-analysis of contemporary randomized controlled trials that compared CABG and MT in patients with stable CAD.

METHODS

A systematic search was performed in January 2021 to identify randomized controlled trials enrolling adult patients with stable CAD, randomized to CABG or MT. Only trials using at least aspirin, beta-blockers, and statins in the MT arm were included. Individual patient data were obtained from all eligible studies and pooled. The primary outcome was all-cause mortality.

RESULTS

Four trials involving 2523 patients (1261 CABG; 1262 MT) were included with a median follow-up of 5.6 (4.0-9.2) years. CABG was associated with increased risk of all-cause mortality within 30 days (hazard ratio [HR], 4.81; 95% confidence interval [CI], 1.95-11.83) but subsequent reduction in the long-term risk of death (HR, 0.79; 95% CI, 0.69-0.89). As such, the cumulative 10-year mortality rate was lower in patients treated with CABG compared with MT (45.1% vs 51.7%, respectively; odds ratio, 0.70; 95% CI, 0.58-0.85). Age and race were significant treatment effect modifier (interaction P = .003 for both).

CONCLUSIONS

In patients with stable CAD, initial allocation to CABG was associated with greater periprocedural risk of death but improved long-term survival compared with MT. The survival advantage for CABG became significant after the fourth postoperative year and was particularly pronounced in younger and non-White patients.

Myocardial Revascularization Surgery: JACC Historical Breakthroughs in Perspective

Coronary artery bypass grafting (CABG) was introduced in the 1960s as the first procedure for direct coronary artery revascularization and rapidly became one of the most common surgical procedures worldwide, with an overall total of more than 20 million operations performed. CABG continues to be the most common cardiac surgical procedure performed and has been one of the most carefully studied therapies. Best CABG techniques, optimal bypass conduits, and appropriate patient selection have been rigorously tested in landmark clinical trials, some of which have resolved controversy and most of which have stoked further debate and trials. The evolution of CABG cannot be properly portrayed without presenting it in the context of the parallel development of percutaneous coronary intervention. In this Historical Perspective, we a provide a broad overview of the history of coronary revascularization with a focus on the foundations, evolution, best evidence, and future directions of CABG.