Novel algorithms to predict 10-year mortality and MACCE after coronary artery bypass grafting

The PRIORITY (PRedictIng long-term Outcomes afteR Isolated coronary artery bypass surgerY) project was designed to identify preoperative risk factors for 10-year all-cause mortality and major adverse cardiac and cerebrovascular events (MACCE) after isolated coronary artery bypass grafting (CABG).

PRIORITY is an observational cohort study merging two prospective multicenter studies conducted in 2002-2004 and 2007-2008 on isolated CABG. Follow-up information was obtained through administrative databases and was truncated 10 years after the intervention. The primary endpoint was long-term all-cause mortality and the secondary endpoint was a composite of MACCE.

The study cohort included 10 989 patients with complete 10-year follow-up. Mortality up to 10 years was associated with almost all variables defined by EuroSCORE and the risk factors with higher impact were left ventricular ejection fraction (LVEF) <30% [hazard ratio (HR) 2.29, 95% confidence interval (CI) 1.95-2.69], diabetes (HR 3.17, 95% CI 2.31-4.34), and cirrhosis (HR 3.90, 95% CI 2.09-7.28). Also, 10-year MACCE was affected by preoperative comorbidities defined by EuroSCORE, with different weights compared with 30-day prediction scores. The risk factors with the worst effect on long-term MACCE were LVEF <30% (HR 1.61, 95% CI 1.39-1.86), dialysis (HR 2.52, 95% CI 1.87-3.40), and cirrhosis (HR 1.93, 95% CI 1.09-3.41). Both scores demonstrated good performance in terms of discrimination and calibration.

The PRIORITY study confirms the importance of long-term follow-up for patients who undergo CABG and has led to the design of online risk calculators for predicting all-cause mortality and MACCE up to 10 years to support the clinical management of patients.