Sudden Cardiac Death in Patients With Ischemic Heart Failure Undergoing Coronary Artery Bypass Grafting

Abstract

Background The risk of sudden cardiac death (SCD) in patients with heart failure following CABG has not been examined in a contemporary clinical trial of surgical revascularization. This analysis describes the incidence, timing and clinical predictors of SCD after CABG. Methods Patients enrolled in the Surgical Treatment of Ischemic Heart Failure (STICH) trial who underwent CABG with or without surgical ventricular reconstruction (SVR) were included. We excluded patients with prior ICD and those randomized only to medical therapy. The primary outcome was SCD as adjudicated by a blinded committee. A Cox model was used to examine and identify predictors of SCD. The Fine and Gray method was used to estimate the incidence of SCD accounting for the competing risk of other deaths. Results Over a median follow-up of 46 months, 113 patients of 1411 patients who received CABG without (n = 934) or with SVR (n = 477) had SCD; 311 died of other causes. The mean LVEF at enrollment was 28±9%. The 5-year cumulative incidence of SCD was 8.5%. Patients who had SCD and those who did not die were younger and had fewer comorbid conditions than those who died for reasons other than SCD. In the first 30 days after CABG, SCD (n=5) accounted for 7% of all deaths. The numerically greatest monthly rate of SCD was in the 31–90 day time period. In a multivariable analysis including baseline demographics, risk factors, coronary anatomy and LV function, ESVI and BNP were most strongly associated with SCD. Conclusions The monthly risk of SCD shortly after CABG among patients with a low LVEF is highest between the first and third month, suggesting that risk stratification for SCD should occur early in the postoperative period, particularly in patients with increased preoperative ESVI and/or BNP. Clinical Trial Registration NCT0002359 (www.stichtrial.org)

Perioperative changes in left ventricular systolic function following surgical revascularization

“…Our results build on a previous analysis of SCD from the STICH trial by Rao et al [26]. Analyzing all 1,411 patients who underwent CABG across the STICH trial, Rao et al observed 113 occurrences of SCD over 5 years for an 8.5% 5-year cumulative incidence of SCD [26]. Notably, SCD risk was greatest in the postoperative window from 30-90 days.…”

“…Previous studies have shown that improvement in LVEF is associated with reduced risk of SCD [23][24][25]. Our results build on a previous analysis of SCD from the STICH trial by Rao et al [26]. Analyzing all 1,411 patients who underwent CABG across the STICH trial, Rao et al observed 113 occurrences of SCD over 5 years for an 8.5% 5-year cumulative incidence of SCD [26].…”

“…Notably, SCD risk was greatest in the postoperative window from 30-90 days. Additionally, while lower preoperative LVEF predicted increased risk of perioperative SCD, increased preoperative end-systolic volume index and B-type natriuretic peptide were the most robust independent predictors of SCD risk [26]. Given the highest risk of SCD was within the first 3 months of CABG, post-CABG LVEF assessments at 4 months, as in current analysis, would fail to capture the LVEF change within PLOS ONE most individuals experiencing SCD [27,28].…”

Secondary prevention of sudden cardiac death

“…Third, although there have been considerable advancements in the mode and care of coronary revascularization since the era of secondary prevention randomized trials, contemporary mode-of-death analyses continue to identify sudden death as a common mechanism of cardiovascular death in patients undergoing percutaneous 77 and surgical revascularization. 78 Future efforts are needed to further refine arrhythmic risk evaluation in secondary prevention patients with ischemic heart disease. Specific populations of interest include those with residual coronary disease and/or ischemia after “culprit lesion” revascularization.…”

Electrical storm – still an extremely poor prognosis. Do these acute states of life-threatening arrhythmias require a multidirectional approach from the start?

“…The recently published results from the Sudden Cardiac Death in Patients With Ischemic Heart Failure Undergoing Coronary Artery Bypass Grafting (STICH) trial indicate that the monthly risk of SCD shortly after CABG among patients with a low LVEF is the highest between the first and the third month. In such patients, especially those with an increased perioperative end-systolic volume index and/or B-type natriuretic peptide, the risk stratification for SCD should occur early in the postoperative period [36].…”