Long-term clinical outcomes of vasodilating beta-blockers in acute myocardial infarction patients with preserved left ventricular ejection fraction after a successful stent implantation

Abstract

The long-term effectiveness of beta-blockers (BB) in acute myocardial infarction (AMI) patients with preserved left ventricular (LV) ejection fraction (EF) remains unclear. Vasodilating beta-blockers may offer additional physiological benefits, yet their long-term clinical impact in this population has not been well defined.

This study assessed the association between vasodilating BB therapy and long-term outcomes in AMI patients with preserved LVEF.

Among 13624 patients who enrolled in the nationwide AMI database of South Korea, the KAMIR-NIH Registry, 6076 AMI patients with preserved LVEF were selected for this study. After 1:2:2 PSM, 485 patients were assigned to the no BB group, while 970 patients each were included in the conventional and vasodilating BB groups. The primary outcome was a composite of cardiac death, recurrent MI, or hospitalization for heart failure during 3-year follow up period.

In the PSM cohort, the primary outcomes occurred in 34 patients (7.0%) in the no BB group, 59 patients (6.1%) in the conventional BB group and 40 patients (4.1%) in the vasodilating BB group. The vasodilating BB group was associated with a significantly lower incidence of the primary outcome compared to the no BB group (HR 0.61, 95% CI 0.39-0.98, P=0.039). Although the event rate in the vasodilating BB group was numerically lower than that in the conventional BB group, the difference was not statistically significant (HR 0.69, 95% CI 0.46-1.03, P=0.067). No significant difference was observed between the conventional BB and no BB groups (HR 0.90, 95% CI 0.59–1.37; P = 0.623).

In AMI patients with preserved LVEF, prescription of vasodilating BB at discharge was associated with better long-term clinical outcomes compared to the use of conventional BB or no BB use.For image description, please refer to the figure legend and surrounding text.For image description, please refer to the figure legend and surrounding text.