Initial optimal medical therapy with or without invasive strategy for stable coronary disease: a meta-analysis and systematic review.

INTRODUCTION There is a persistent controversy regarding the benefit and timing of angiography in patients with stable coronary artery disease (CAD). With this meta-analysis of randomized controlled trials (RCTs) the advantages of initial invasive strategy and medical therapy compared with only medical therapy. METHODS We conducted a literature search of the following databases Pubmed/MEDLINE, Cochrane Library and Embase. Data was collected from all the RCTs that compared early invasive approach with medical therapy alone in treating stable CAD which was conducted by two independent authors. Primary outcomes were all-cause mortality and myocardial infarction (MI), while the secondary outcomes included major adverse cardiovascular events (MACE), cardiovascular mortality, cardiovascular hospitalization, hospitalization due to unstable angina and revascularization events. The Mantel-Haenszel random-effects model was used to estimate risk ratios (RRs) and 95% confidence intervals (CIs). RESULTS We included 15 RCTs (13 916 patients, mean age 63.1, 78.9% men). The early invasive strategy, compared with medical therapy alone, did not reveal a significant reduction in the incidence of all-cause mortality (RR, 0.94; 95% CI, 0.84-1.05, P = 0.30) or MI (RR, 0.93; 95% CI, 0.79-1.10, P = 0.42). Furthermore, the early invasive strategy did not reduce the incidence of cardiovascular mortality, cardiovascular hospitalization or the revascularization rate compared with medical therapy alone (P > 0.05). However, the incidence of MACE and hospitalization due to unstable angina were lower in patients treated with early invasive strategy (RR, 0.79; 95% CI, 0.63-0.99, P = 0.04), and (RR, 0.46; 95% CI, 0.32-0.67, P < 0.0001), respectively. CONCLUSIONS Early invasive strategy with medical therapy did not reduce the incidence of all-cause mortality and MI when compared with medical therapy alone among patients with stable CAD with significant stenosis. However, there was a significant reduction in the incidence of MACE and hospitalization due to unstable angina in the early invasive group.