Heart Disease Weekly

Researchers from Laval University publish new studies and findings in the area of angiotensins

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"There is currently no medical treatment proven effective to slow the evolution of this cardiomyopathy. Vasodilators were once thought to have protective effects, but recent publications have cast some doubts about their effectiveness. We hypothesized that drugs targeting the renin-angiotensin system should be more effective than those having no direct effect on the renin-angiotensin system. We designed a protocol comparing the effects of 3 vasodilators in a rat AR model (n=9 to I I animals per group). The effects of a 6-month treatment of (1) nifedipine, (2) captopril, or (3) losartan were compared in mate AR rats. Sham-operated and untreated AR animals were used as controls. Nifedipine-treated animals displayed hemodynamics, LV dilatation, hypertrophy, and loss of function similar to those of the untreated group. Both captopril and losartan were effective in improving hemodynamics, slow LV dilatation, hypertrophy, and dysfunction. Gene expression analysis confirmed the lack of effects of the nifedipine treatment at the molecular level. Using an animal model of severe AR, we found that vasodilators targeting the renin-angiotensin system were effective to slow the development of LV remodeling and to preserve LV function," wrote E. Plante and colleagues, Laval University.

The researchers concluded: "As recently shown in the most recent human clinical trial, nifedipine was totally ineffective. targeting the renin-angiotensin system seems a promising avenue in the treatment of this disease, and clinical trials should be carefully designed to re-evaluate the effectiveness of angiotensin I-converting enzyme inhibitors or angiotensin 11 receptor blockers in AR. (Circ Heart Fail. 2009;2:25-32.)."

Plante and colleagues published their study in Circulation - Heart Failure (Comparative Study of Vasodilators in an Animal Model of Chronic Volume Overload Caused by Severe Aortic Regurgitation. Circulation - Heart Failure, 2009;2(1):25-32).

For more information, contact M. Arsenault, Laval University, Hopital Laval, Center Rech, Group Rech Valvulopathies, Institute Cardiology Quebec, 2725 Chemin St. Foy, Ste. Foy, PQ G1V 4G5, Canada.

Publisher contact information for the journal Circulation - Heart Failure is: Lippincott Williams & Wilkins, 530 Walnut St., Philadelphia, PA 19106-3621, USA.

Keywords: Canada, Angiotensins, Angiotensin, Angiotensin II Receptor Antagonist, Antiarrhythmic, Antihypertensive, Captopril, Cardiology, Cardiomyopathies, Cardiomyopathy, Clinical Trial Research, Critical Care Medicine, Drugs, Heart Disease, Heart Failure, Hypertrophy, Losartan, Nifedipine, Pharmaceuticals, Therapy, Treatment, Laval University.

This article was prepared by Heart Disease Weekly editors from staff and other reports. Copyright 2009, Heart Disease Weekly via NewsRx.com.