The negative impact of incomplete angiographic revascularization on clinical outcomes and its association with total occlusions: the SYNTAX (Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery) trial

Abstract

Objectives: The study sought to evaluate the clinical impact of angiographic complete (CR) and incomplete (ICR) revascularization and its association with the presence of total occlusions (TO), after percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) surgery in the "all-comers" SYNTAX (Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery) trial.

Background: In patients with complex coronary artery disease undergoing PCI or CABG, the long-term prognostic implications of CR versus ICR is unsettled.

Methods: In this post hoc study, consisting of randomized (n = 1,800) and nested PCI (n = 198) and CABG (n = 649) registries, 4-year clinical outcomes were compared in groups, with and without angiographic CR, in the PCI and CABG arms. Clinical outcomes were analyzed with Kaplan-Meier estimates, log-rank comparisons, and Cox regression analyses. Multivariate predictors of ICR were determined. Similar analyses were undertaken in the TO and non-TO treated groups of both study arms.

Results: Angiographic CR was achieved in 52.8% of the PCI arm and 66.9% of the CABG arm. Within the PCI and CABG arms, ICR (compared with CR) seemed to be a surrogate marker of a greater burden of anatomical coronary complexity and clinical comorbidity and was associated with significantly higher frequencies of 4-year mortality, all-cause revascularization, stent thrombosis (PCI arm), and major adverse cardiac and cerebrovascular events. The presence of a TO was the strongest independent predictor of ICR after PCI (hazard ratio: 2.70, 95% confidence interval: 1.98 to 3.67, p < 0.001). Eight hundred and forty patients (PCI: 26.3%, CABG: 36.4%, p < 0.001) were identified to have 1,007 TOs, with 68.1% of TOs located in the proximal-mid coronary vasculature. The findings associating ICR (compared with CR) with higher frequencies of 4-year mortality and major adverse cardiac and cerebrovascular events remained consistent in the TO-treated groups in the PCI and CABG arms.

Conclusions: Within the PCI and CABG arms of the all-comers SYNTAX trial, angiographically determined ICR has a detrimental impact on long-term clinical outcomes, including mortality. This effect remained consistent in patients with and without TOs.