NPPB and myocardial infarction: Compared with the MI+PBS (control) group, the serum N‐terminal pro‐brain natriuretic peptide (NT‐proBNP) concentration, and the values of left ventricular end‐diastolic diameter (LVDd) and left ventricular end‐systolic diameter (LVDs) of the MI+AAV‐ELA (gene therapy) group were significantly decreased, while the value of left ventricular ejection fraction was significantly increased at 2 and 4 weeks after operation.