Myocardial contractile reserve by contrast and low-dose dobutamine echocardiography predicts 6-month left ventricular reverse remodeling after sacubitril/valsartan in ischemic cardiomyopathy

The response of left ventricular reverse remodeling (LVRR) following sacubitril/valsartan therapy varies substantially among patients with ischemic cardiomyopathy (ICM). Conventional clinical indicators have limited ability to identify myocardial recovery potential and predict treatment response. This study investigated the predictive value of myocardial contractile reserve assessed by stress echocardiography for LVRR after sacubitril/valsartan treatment. In this study, 174 patients with ICM underwent baseline evaluation and initiated sacubitril/valsartan therapy. Left heart contrast echocardiography and low-dose dobutamine stress echocardiography was performed before treatment. Myocardial contractile reserve was evaluated using changes in left ventricular ejection fraction (ΔLVEF), wall motion score index (ΔWMSI), and the number of contractile reserve-positive segments. LVRR was defined as a ≥ 15% reduction in left ventricular end-systolic volume index (LVESVI) at 24 ± 2 weeks compared with baseline. Logistic regression, receiver operating characteristic (ROC) analysis, incremental model assessment, and sensitivity analyses were performed. Of the 164 patients who completed follow-up, 67 (40.85%) achieved LVRR. Compared with the non-LVRR group, patients with LVRR exhibited significantly greater myocardial contractile reserve, characterized by higher ΔLVEF, lower ΔWMSI, and a greater number of contractile reserve-positive segments (all P < 0.05). After adjustment for clinical variables, all three indices remained independently associated with LVRR (all P < 0.001). The corresponding AUC values were 0.84, 0.80, and 0.82, respectively. Adding ΔLVEF to the clinical model improved the AUC from 0.70 to 0.88 ( P < 0.001). Myocardial contractile reserve is a strong predictor of left ventricular reverse remodeling after 6 months of sacubitril/valsartan therapy in patients with ischemic cardiomyopathy and may facilitate individualized risk assessment for reverse remodeling following treatment. Because all participants received sacubitril/valsartan, these findings should not be interpreted as demonstrating treatment-specific response classification. Clinical trial registration This observational study was approved by the institutional ethics committee. Clinical trial registration was not required according to local regulations.