Ten-year survival benefit and appropriateness of surgical versus percutaneous revascularization in synergy between percutaneous coronary intervention with Taxus and cardiac surgery randomized trial

Objectives: Average treatment effects from randomized trials do not reflect the heterogeneity of an individual's response to treatment. This study evaluates the appropriate proportions of patients for coronary artery bypass grafting, or percutaneous intervention based on the predicted/observed ratio of 10-year all-cause mortality in the SYNTAX population.

Methods: The study included 1800 randomized patients and 1275 patients in the nested percutaneous (n = 198) or surgical (n = 1077) registries. The primary end point was 10-year all-cause mortality. The SYNTAX score II-2020 was validated internally in the randomized cohort and externally in the registry cohort. Proportions of patients with survival benefits from coronary artery bypass grafting or percutaneous intervention were determined using SYNTAX score II-2020.

Results: Ten-year mortality was 23.8% for coronary artery bypass grafting, 28.6% for percutaneous intervention in the randomized cohort, 27.6% for coronary artery bypass grafting and 55.4% for percutaneous intervention in the registries. In the coronary artery bypass grafting registry, the SYNTAX score II-2020 predicted 10-year mortality with helpful calibration and discrimination (C-index: 0.70, intercept: 0.00, slope: 0.76). The proportion of patients deriving a predicted survival benefit from coronary artery bypass grafting over percutaneous intervention was 82.4% (2143/2602) and 17.7% (459/2602) for the entire SYNTAX trial population, translating into a 4.7 to 1 appropriate ratio of treatment allocation to coronary artery bypass grafting and percutaneous intervention.

Conclusions: Choosing a revascularization modality should depend on an individual's long-term prognosis rather than average treatment effects. Additionally, patients should be informed about their predicted prognosis.

Trial registration: Registered on clinicaltrial.gov.

Syntaxes: NCT03417050 (https://clinicaltrials.gov/ct2/show/NCT03417050).

Syntax: NCT00114972 (https://www.clinicaltrials.gov/ct2/show/NCT00114972).