Incremental Value of the Preoperative Echocardiogram to Predict Mortality and Major Morbidity in Coronary Artery Bypass Surgery

Abstract

Background— Although echocardiography is commonly performed before coronary artery bypass surgery, there has yet to be a study examining the incremental prognostic value of a complete echocardiogram. Methods and Results— Patients undergoing isolated coronary artery bypass surgery at 2 hospitals were divided into derivation and validation cohorts. A panel of quantitative echocardiographic parameters was measured. Clinical variables were extracted from the Society of Thoracic Surgeons database. The primary outcome was in-hospital mortality or major morbidity, and the secondary outcome was long-term all-cause mortality. The derivation cohort consisted of 667 patients with a mean age of 67.2±11.1 years and 22.8% females. The following echocardiographic parameters were found to be optimal predictors of mortality or major morbidity: severe diastolic dysfunction, as evidenced by restrictive filling (odds ratio, 2.96; 95% confidence interval, 1.59-5.49), right ventricular dysfunction, as evidenced by fractional area change <35% (odds ratio, 3.03; 95% confidence interval, 1.28-7.20), or myocardial performance index >0.40 (odds ratio, 1.89; 95% confidence interval, 1.13-3.15). These results were confirmed in the validation cohort of 187 patients. When added to the Society of Thoracic Surgeons risk score, the echocardiographic parameters resulted in a net improvement in model discrimination and reclassification with a change in c-statistic from 0.68 to 0.73 and an integrated discrimination improvement of 5.9% (95% confidence interval, 2.8%-8.9%). In the Cox proportional hazards model, right ventricular dysfunction and pulmonary hypertension were independently predictive of mortality over 3.2 years of follow-up. Conclusions— Preoperative echocardiography, in particular right ventricular dysfunction and restrictive left ventricular filling, provides incremental prognostic value in identifying patients at higher risk of mortality or major morbidity after coronary artery bypass surgery.

Risk Prediction in Aortic Valve Replacement: Incremental Value of the Preoperative Echocardiogram

“…In the current study, as in our previous study of patients undergoing isolated CABG,7 measures of LV diastolic dysfunction and RV dysfunction emerged as the main incremental predictors of postoperative outcomes. Moreover, measures of LV remodeling and low mean aortic gradient emerged as strong predictors of postoperative outcomes in the setting of SAVR, reflecting the deleterious effect of this phenotypic response to chronic pressure overload.…”

“…This represents a missed opportunity to enhance risk prediction given the wealth of hemodynamic, functional, and structural data available in routinely performed preoperative echocardiograms. Recently, our group demonstrated the incremental prognostic value of preoperative echocardiograms in patients undergoing isolated CABG 7. Thus, we expanded this hypothesis to patients undergoing SAVR to determine the incremental prognostic value of the echocardiogram in addition to the STS risk score to predict short‐ and long‐term mortality and major morbidity.…”

Derivation and Validation of Prognosis-Based Age Cutoffs to Define Elderly in Cardiac Surgery

“…Inclusion criteria were (1) coronary artery bypass graft surgery (CABG), valve repair or replacement surgery, or combined CABG plus valve surgery performed during the study timeframe; (2) case captured by the STS Adult Cardiac Surgery Database for the Boston sites or by the Pre-Operative Surgical Stratification by Echocardiography (POSSE) database for the Montreal site 9 ; and (3) age ≥50 years at the time of surgery. Elective, urgent, and emergent surgeries were included.…”

Echocardiographic Predictors of Immediate Postoperative Outcomes in Patients With Severe Left Ventricular Systolic Dysfunction Undergoing On-Pump Coronary Artery Bypass Grafting

“…11 Afilao et al observed preoperative RV dysfunction and restrictive LV filling as powerful predictors of mortality or major morbidity after CABG, whereas RV dysfunction and pulmonary hypertension predicted long-term mortality over 3.2 years. 16 The right ventricle fractional area change has found to be predictive of inotropes requirement and ventilator hours in early postoperative period in patients with severe LV dysfunction undergoing CABG. 17 Longitudinal strain incrementally improves the risk stratification of both valvular and CABG surgery patients obtained even with the recently proposed Euro-SCORE II.…”