A long-term prevention study with oxprenolol in coronary heart disease

Area of Science:

• Cardiology
• Clinical Trials
• Pharmacology

Background:

• Secondary prevention after myocardial infarction (MI) is crucial for improving patient outcomes.
• The role of beta-blockers in long-term post-MI management requires further investigation, particularly regarding treatment timing.

Purpose of the Study:

• To evaluate the efficacy of low-dose oxprenolol in secondary prevention following acute myocardial infarction.
• To determine if the timing of oxprenolol initiation influences its impact on mortality and cardiac events.

Main Methods:

• A randomized, double-blind, placebo-controlled trial involving 1103 men aged 35-65 with a history of MI.
• Participants received either 40mg oxprenolol or placebo twice daily for seven years.
• Analysis stratified by the time of treatment initiation post-MI.

Main Results:

• Overall, no significant difference in mortality or cardiac events was observed between oxprenolol and placebo groups.
• Early treatment (within 4 months post-MI) showed a significant increase in 6-year survival with oxprenolol (77% to 95%, P<0.001).
• Late treatment (1-7.5 years post-MI) was associated with a reduced 6-year survival rate in the oxprenolol group (92% to 79%, P=0.002).

Conclusions:

• Low-dose oxprenolol is beneficial for secondary prevention in patients treated relatively soon after myocardial infarction.
• Initiating oxprenolol therapy several years after MI may be detrimental, potentially due to late adverse effects after treatment withdrawal.
• Treatment timing is a critical factor influencing the effectiveness of oxprenolol in post-MI secondary prevention.