In SYNTAX, using an “all comers” design, patients with de novo 3-VD and/or LM disease were screened for study suitability by a local Heart Team that was composed of an interventional cardiologist, a cardiac surgeon, and the study coordinator. If the consensus decision was that comparably complete revascularization could be achieved by either PCI or CABG therapy, the patient was randomized to one of the treatment options. A total of 903 patients were assigned to PCI using TAXUS Express paclitaxel-eluting stents (Boston Scientific, Natick, Mass) and 897 patients were assigned to CABG surgery.
The primary study end point for the randomized cohort was the overall MACCE rate at 12 months’ follow-up, but patients were followed up to 5 years after allocation. The SYNTAX study also included two nested registries, one for PCI-ineligible patients (CABG registry) and one for CABG-ineligible patients (PCI registry). A total of 1079 patients were allocated to the CABG registry. Reasons not to randomize these patients were predominantly complex coronary anatomy (70.9%) and potentially untreatable coronary chronic total occlusion (22.0%). All patients were subdivided in three groups of escalating SYNTAX Score Risks. The raw SYNTAX score was predictive of outcomes in patients who underwent PCI but not for CABG.
Ultimately, a total of 1541 SYNTAX CABG patients were assigned to 5 years’ follow-up and analyzed for the current study (897 randomized and 644 registry patients). Overall 2-year follow-up was available on 1468 CABG patients, corresponding to a follow-up rate of 95.3%.