Abstract
BACKGROUND: The left ventricular pressure-strain loop (LV-PSL) technique, which is noninvasive and independent of pressure load, is more sensitive than is left ventricular speckle tracking imaging in detecting subtle changes in myocardial function. This study evaluated the improvement in cardiac function after application of LV-PSL in patients with heart failure with reduced ejection fraction (HFrEF) after acute myocardial infarction (MI) treated with sacubitril/valsartan plus dapagliflozin as compared to treatment with sacubitril/valsartan monotherapy. METHODS: This prospective, multicenter, open-label study recruited 60 MI survivors with HFrEF between March 2021 and June 2022. The patients were randomly assigned in 1:1 groups, as stratified by center. Patients were randomly categorized into either an observation group [n=30; conventional treatment + 100 mg (49/51 mg) of sacubitril/valsartan, + 10 mg of dapagliflozin] or a control group [n=30; conventional treatment + 100 mg (49/51 mg) of sacubitril/valsartan]. Patients were assessed at three time points: 1 month after discharge (T1), 3 months after discharge (T3), and 6 months after discharge (T6). Two-dimensional ultrasound images were routinely collected, two-dimensional speckle tracking imaging was applied to calculate the left ventricular global longitudinal strain (LV-GLS) rate for both groups, and LV-PSL analysis was used for the assessment of myocardial work, including global work index (GWI), global constructive work (GCW), global wasted work, and global work efficiency. The results at the three follow-up visits were compared with the predischarge results (baseline, T0). RESULTS: Compared with the values at T0, the LV-GLS and left ventricular myocardial work index (LVMWI) values increased in both the observation and control groups at T1, T3, and T6, with GWI and GCW showing significantly greater improvement in the observation group at T6 (GWI: 1,204±336 vs. 987±417 mmHg%, P=0.03; GCW: 1,401±348 vs. 1,206±356 mmHg%, P=0.04). Survival analysis revealed that the overall incidence of major adverse cardiovascular events (MACEs) in the observation group was significantly lower than that in the control group (P=0.03). In a multivariate logistic regression analysis including GCW, GWI, GLS, and left ventricular eject fraction (LVEF), GCW emerged as the only independent predictor of occurrence of MACEs (odds ratio =1.08; 95% CI: 0.63-0.93; P<0.001). CONCLUSIONS: Sacubitril/valsartan and dapagliflozin combination therapy led to a moderate improvement of cardiac function in patients with post-MI heart failure (P-MI-HF) compared to treatment with sacubitril/valsartan alone. Moreover, LV-PSL analysis can be used to assess the early prognosis of patients with P-MI-HF.