Geographic variation in the treatment of acute myocardial infarction in the VALsartan In Acute myocardial iNfarcTion (VALIANT) trial.

BACKGROUND

The VALIANT trial compared the efficacy and safety of captopril, valsartan, and their combination in patients with left ventricular systolic dysfunction, heart failure, or both after acute myocardial infarction (MI). By examining this international trial population of high-risk patients, we sought to determine geographic variations in the use of 3 key treatments for MI.

METHODS

We analyzed data from 14,512 high-risk patients with MI in the VALIANT trial from the 20 countries that had enrolled >100 patients. International variation in the proportion of patients receiving (1) reperfusion therapy (thrombolysis or primary percutaneous coronary intervention), (2) beta-blockers, or (3) aspirin at the time of MI was measured by using adjusted W scores. These scores correspond to the number of additional or fewer patients who received each of the therapies compared with the number expected, as estimated from multivariable regression models that account for patients' baseline characteristics.

RESULTS

There was marked variation between countries in the use of reperfusion therapy (equivalent to a difference of up to 36/100 potentially eligible patients) and beta-blockers (41/100), whereas there was much less variation in the use of aspirin (13/100).

CONCLUSIONS

Marked geographic variation persists in the use of standard evidence-based therapy advocated by international guidelines. Our findings have implications not only for care of patients but also for the conduct of international trials.