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

J Thorac Cardiovasc Surg. 2022 Jan;163(1):111-119.e2. doi: 10.1016/j.jtcvs.2020.03.040. Epub 2020 Mar 21.

Abstract

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, 1.30 [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 [1.37-1.55]; <25%, hazard ratio, 1.68 [1.58-1.79]). 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.

Keywords: coronary artery bypass grafting; ejection fraction; failure to rescue; postoperative complications; survival.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Coronary Artery Bypass* / adverse effects
  • Coronary Artery Bypass* / methods
  • Coronary Artery Disease* / complications
  • Coronary Artery Disease* / diagnosis
  • Coronary Artery Disease* / physiopathology
  • Coronary Artery Disease* / surgery
  • Early Medical Intervention / standards
  • Female
  • Humans
  • Long Term Adverse Effects* / diagnosis
  • Long Term Adverse Effects* / mortality
  • Long Term Adverse Effects* / physiopathology
  • Long Term Adverse Effects* / prevention & control
  • Male
  • Middle Aged
  • Postoperative Complications* / diagnosis
  • Postoperative Complications* / etiology
  • Postoperative Complications* / physiopathology
  • Postoperative Complications* / therapy
  • Preventive Health Services
  • Quality Improvement
  • Risk Assessment
  • Stroke Volume
  • Survival Analysis
  • Time-to-Treatment / standards
  • United States
  • United States Department of Veterans Affairs
  • Ventricular Dysfunction, Left* / complications
  • Ventricular Dysfunction, Left* / diagnosis
  • Ventricular Dysfunction, Left* / physiopathology
  • Ventricular Dysfunction, Left* / therapy