The impact of a dose of the angiotensin receptor blocker valsartan on post-myocardial infarction ventricular remodelling.

AIMS: Although clinical guidelines advocate the use of the highest tolerated dose of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers after acute myocardial infarction (MI), the optimal dosing or the risk-benefit profile of different doses have not been fully identified.

METHODS AND

RESULTS

In this multicentre trial, 495 Korean patients with acute ST segment elevation MI and subnormal left ventricular (LV) ejection fraction (<50%) were randomly allocated (2:1) to receive maximal tolerated dose of valsartan (titrated up to 320 mg/day, n = 333) or low-dose valsartan (80 mg/day, n = 162) treatment. The primary objective was to assess the changes in echocardiographic parameters of LV remodelling from baseline to 12 months after discharge. After treatment, end-diastolic LV volume (LVEDV) decreased significantly in the low-dose group, but the difference in LVEDV changes was insignificant between the maximal-tolerated-dose and low-dose groups. End-systolic LV volume decreased significantly in both groups, to a similar degree between groups. LV ejection fraction rose significantly in both study groups, to a similar degree. Changes in plasma levels of neurohormones were also comparable between the two groups. Drug-related adverse effects occurred more frequently in the maximal-tolerated-dose group than in the low-dose group (7.96 vs. 0.69%, P < 0.001).

CONCLUSIONS

In the present study, treatment with the maximal tolerated dose of valsartan did not exhibit a superior effect on post-MI LV remodelling compared with low-dose treatment and was associated with a greater frequency of adverse effect in Korean patients. Further study with a sufficient number of cases and statistical power is warranted to verify the findings of the present study.