European Journal of Preventive Cardiology | 2019
Meta-analysis of long-term outcomes of percutaneous coronary intervention versus medical therapy in stable coronary artery disease
Abstract
Percutaneous coronary intervention (PCI) improves survival and reduces the risk of recurrent myocardial ischemia in patients with acute coronary syndrome. Conversely, the role of PCI in patients with stable coronary artery disease (CAD) remains controversial. In the ORBITA trial, PCI was not associated with significant improvement in exercise time or angina frequency compared with a sham procedure, whereas long-term outcomes of the FAME 2 trial showed that a fractional flow reserve (FFR)-guided PCI strategy was superior to medical therapy (MT) in terms of cardiovascular outcomes. To address this controversy, we have performed an updated meta-analysis comparing the efficacy of PCI versus MT at a mean follow-up duration of 5 years. A comprehensive search strategy was devised using MEDLINE, EMBASE and CENTRAL (inception to 30 May 2018) to identify randomized controlled trials (RCTs) with a sample size greater than 400 patients (to avoid small study effects) and over 4 years follow-up duration. We included trials reporting PCI with stent implantation in 70% or more of the patients and statin therapy in 50% or more patients in the study population. The outcomes of interest were all-cause mortality, myocardial infarction (MI), stroke, cardiovascular mortality, revascularization and angina relief. Quality assessment of each trial was performed using the Cochrane risk of bias tool. The literature search, data extraction and bias risk assessment was done by authors ANL, MSK and UF independently. Estimates were pooled using the DerSimonian and Laird random effects model and reported as risk ratio (RR) with 95% confidence interval (CI). Heterogeneity was quantified by I with values greater than 75% consistent with high grade heterogeneity. Publication bias was assessed using Egger’s regression test. Analyses were conducted at 5% significance. Comprehensive Meta-Analysis (version 3) was used for meta-analysis. Five RCTs (8117 patients) 3,5–8 were finalized in this meta-analysis (Table 1). At a mean follow-up duration of 5 years, there were no significant differences between PCI and MT in terms of all-cause mortality (RR 0.99, 95% CI 0.86–1.15, P1⁄4 0.95, I1⁄4 0%), MI (RR 1.00, 95% CI 0.80–1.25, P1⁄4 0.99, I1⁄4 54%), stroke (RR 1.14, 95% CI 0.83–1.57, P1⁄4 0.43, I1⁄4 0%), revascularization (RR 0.61, 95% CI 0.28–1.31, P1⁄4 0.21, I1⁄4 97%), cardiovascular mortality (RR 1.06, 95% CI 0.82–1.36, P1⁄4 0.67, I1⁄4 0%) or angina relief (RR 1.03, 95% CI 0.93–1.15, P1⁄4 0.54, I1⁄4 66%) (Figure 1). Egger’s regression test did not detect publication bias (P (two-tailed)1⁄4 0.19). This meta-analysis suggests that in patients with stable CAD, PCI was not associated with a reduction in cardiovascular outcomes, angina relief or survival benefit compared with MT at 5 years mean follow-up duration. The former meta-analyses included studies with shorter follow-ups with the lesser use of stents, which is contrary to the current standard of care. The current study is unique because of the inclusion of more contemporary trials with longer follow-up durations and studies in which the use of stents ranged from 72% to 97% in the PCI arm. Therefore, these