Abstract 15545: Incremental Prognostic Value of Echocardiographic Markers of Left Ventricular Remodeling and Diastolic Function in the Surgical Treatment for Ischemic Heart Failure Trial
Introduction: Whether echocardiographic (echo) markers of left ventricular (LV) remodeling and diastolic dysfunction contribute incremental and independent prognostic information to clinical risk markers in patients (Pts) with coronary artery disease and severe LV systolic dysfunction is unclear. We sought to determine which echo variables provide the greatest prognostic value in the Surgical Treatment for Ischemic Heart Failure (STICH) population. Methods: Pts enrolled in STICH for whom transmitral Doppler (E/A ratio) was available on a baseline echo interpreted by an echo core laboratory blinded to treatment and outcomes formed the analysis cohort. Comprehensive datasets to account for missing echo data were created by multiple imputation and the impact on all-cause mortality was determined with the Cox’s regression model. Results: E/A ratio could be measured in 1511 of the 2136 Pts enrolled in STICH. Amongst markers of diastolic dysfunction, E/A ratio was the most significant predictor of mortality (χ 2 41.05, p <0.001) with a non-linear, u-shaped, relationship. Mortality was lowest with E/A ratio = 1.0, and increased for E/A ratio <0.6 and >1.0 up to 2.3, beyond which there was no further increase in risk. The combination of larger LV end-systolic volume index (LVESVI), low or high E/A ratio, and mitral regurgitation severity grade, had highly significant incremental negative effects on mortality (χ 2 69.65, p<0.001) when added to a multivariable model with clinical risk markers. Overall, creatinine (χ 2 30.00, p <0.001), followed by LVESVI (χ 2 27.26, p<0.001), age, and E/A ratio (χ 2 12.46, p<0.001) were among the most significant predictors of mortality and accounted for 74% of the total prognostic information. LVESVI and E/A ratio were stronger predictors of poor prognosis than New York Heart Association (NYHA) functional class, hemoglobin, diabetes, stroke, or atrial fibrillation. Conclusions: Echo markers of advanced LV remodeling and diastolic dysfunction add incremental prognostic value to clinical risk markers and are more predictive of poor prognosis than advanced NYHA functional class or anemia. LVESVI and E/A ratio outperformed other echo markers and should be considered standard in assessing risk in Pts with ischemic LV dysfunction.
Clinical Characteristics and Outcomes of Patients with and without Diabetes in the Surgical Treatment for Ischemic Heart Failure (STICH) Trial
Abstract Aims Hypothesis 1 of the Surgical Treatment for Ischemic Heart Failure (STICH) trial enrolled 1212 patients with an LVEF of ≤35% and CAD amenable to coronary artery bypass grafting (CABG). Patients were randomized to CABG and optimal medical therapy (MED) or MED alone. The objective was to assess whether or not patients with diabetes mellitus (DM) enrolled in the STICH trial would have greater benefit from CABG than patients without DM. Methods and results The characteristics and clinical outcomes of patients with and without DM randomized to CABG and MED or MED alone were compared. DM was present in 40%. At baseline, patients with DM had more triple vessel CAD, higher LVEF, and smaller left ventricular volumes. In patients with DM, the primary outcome of all-cause mortality occurred in 39% of patients in the MED group and 39% in the CABG group [hazard ratio (HR) with CABG 0.96, 95% confidence interval (CI) 0.73–1.26]. In patients without DM, the primary outcome occurred in 41% of patients in the MED group and 32% in the CABG group (HR with CABG 0.80, 95% CI 0.63–1.02). While numerically it would appear that the treatment effect of CABG is blunted in patients with DM, there was no significant interaction between DM and treatment group on formal statistical testing. Conclusions Patients with DM enrolled in the STICH trial had more triple vessel disease, smaller hearts, and higher LVEF than those without DM. CABG did not exert greater benefit in patients with DM.