Low left ventricular ejection fraction, complication rescue, and long-term survival after coronary artery bypass grafting

Objectives: To evaluate the association between low left ventricular ejection fraction (LVEF), complication rescue, and long-term survival after isolated coronary artery bypass grafting. Methods: National cohort study of patients who underwent isolated coronary artery bypass grafting (2000-2016) using Veterans Affairs Surgical Quality Improvement Program data. Left ventricular ejection fraction was categorized as >= 35% (n = 55,877), 25%-34% (n = 3893), or <25% (n = 1707). Patients were also categorized as having had no complications, 1 complication, or more than 1 complication. The association between LVEF, complication rescue, and risk of death was evaluated with multivariable Cox regression. Results: Among 61,477 patients, 6586 (10.7%) had a perioperative complication and 2056 (3.3%) had multiple complications. Relative to LVEF >= 35%, decreasing ejection fraction was associated with greater odds of complications (25%-34%, odds ratio, 130 [1.18-1.42]; <25%, odds ratio, 1.65 [1.43-1.92]). There was a dose-response relationship between decreasing LVEF and overall risk of death ( >= 35% [ref]; 25%-35%, hazard ratio, 1.46 [137-1.55]; <25%, hazard ratio, 1.68 [1.581.79]). Among patients who were rescued from complications, there were decreases in 10-year survival, regardless of LVEF. Among those rescued after multiple complications, LVEF was no longer associated with risk of death. Conclusions: While decreasing LVEF is associated with post-coronary artery bypass grafting complications, patients rescued from complications have worse long-term survival, regardless of left ventricular function. Prevention and timely treatment of complications should remain a focus of quality improvement initiatives, and future work is needed to mitigate their long-term detrimental impact on survival.

Automated summary

This study aimed to evaluate the association between low left ventricular ejection fraction (LVEF), complication rescue, and long-term survival after coronary artery bypass grafting. It was found that decreasing LVEF was associated with increased odds of complications and overall risk of death. Patients who were rescued from complications had worse long-term survival regardless of their left ventricular function.