Beta-blockers face fresh scrutiny after MI, especially with preserved heart function. The REBOOT trial's new analysis splits outcomes into acute and chronic phases. This helps doctors weigh therapy benefits clearly.
Study Design and Cohorts
Researchers used REBOOT trial data for this pre-specified landmark analysis. They divided patients into two groups post-MI. Cohort 1 covered the ACS phase in the first year (n = 8,438). Cohort 2 looked at the CCS phase beyond 1 year (n = 7,783 event-free patients). The primary endpoint tracked all-cause death, nonfatal reinfarction, or heart failure hospitalization.
Event Rates Across Phases
A total of 623 primary events occurred. In the first year, 238 events happened at 28.9/1,000 patient-years. Later, 385 events arose at 19.3/1,000 patient-years. Beta-blocker use stayed high overall. Yet, patients with early events got them less often than those with late or no events.
No Benefits in Either Phase
Beta-blockers linked to no lower risk of primary or component outcomes in ACS or CCS phases. A weak trend toward benefit showed in the first year for LVEF 41–49%. In CCS, higher doses tied to worse outcomes. This held for invasively treated MI patients with LVEF >40%.
Guideline Shifts Ahead
These results question routine beta-blockers in this group. Long-term users may qualify for deprescription. Findings urge guideline updates to match real-world outcomes.