Data are limited regarding the impact of acute coronary syndromes (ACSs) on the relative benefits of coronary artery bypass grafting (CABG) versus stent-assisted percutaneous coronary intervention (PCI).
The SoS trial compared patients with multivessel disease who were randomly assigned to CABG (n = 500) or stent-assisted PCI (n = 488). The impact of treatment on 1-year outcomes was compared in ACS (n = 126, CABG; n = 116, PCI) and non-ACS (n = 374, CABG; n = 372, PCI) subgroups.
Baseline characteristics were similar between treatment groups within ACS and non-ACS groups, as was the 1-year composite incidence of mortality and myocardial infarction (ACS, 5.2% for PCI vs 5.6% for CABG, P = .89; non-ACS, 7.0% vs 8.3%, P = .50). The need for repeat revascularizations was higher after PCI versus CABG within each subgroup (ACS, 15.5% vs 7.1%, P = .04; non-ACS, 18.0% vs 3.2%, P < .001). At 6 and 12 months, scores on the Seattle Angina Questionnaire improved significantly in patients with and without ACS. In patients without ACS, CABG was associated with greater improvement in physical limitation, angina frequency, and quality of life at 6 and 12 months. In patients with ACS, there was only a nonsignificant slight trend toward greater improvement with CABG at 1 year. The total 1-year costs for PCI and CABG in patients without ACS were 5760 pound sterling and 8509 pound sterling (Delta = 2749 pound sterling, 95% CI 1890 pound sterling - 3409 pound sterling), and in patients with ACS, 8014 pound sterling and 10080 pound sterling (Delta = 2066 pound sterling, 95% CI -690 pound sterling to 3487 pound sterling).
In patients with and without ACS, CABG had similar clinical outcomes, less need for repeat revascularization and higher costs compared to PCI. The benefit of CABG relative to PCI in improving patients' health status tended to be greater in patients without ACS than in patients with ACS.