By: Thomas Pickering, MD, DPhil, FRCP, Director of Integrative and Behavioral Cardiology Program
of the Cardiovascular Institute at Mount Sinai School of Medicine, New York.

Congestive heart failure is on of the major outcomes of hypertension, and unlike coronary heart disease, the death rate resulting from it is showing so sign of decreasing. It is caused by weakening of the heart muscle, and its symptoms are weakness and shortness of breath.

It has been suggested that angiotensin receptor blockers (ARB) such as Losartan may be superior to ACE inhibitors at preventing the progression of heart failure. The two classes of drug work in a somewhat similar way, since both antagonize the effect of angiotensin, although the angiotensin receptor blockers cause less cough. One of the reasons for thinking that the ARBs might be better than ACE inhibitors (the standard treatment) was the ELITE study (Losartan Heart Failure Survival Study), which was a pilot study for the larger ELITE II, and in which 722 elderly patients with failing hearts were given either losartan or an ACE inhibitor (captopril). The mortality was nearly 50% lower in the losartan group, mainly because less people in the losartan group died suddenly. The rates of hospitalization for heart failure were not different in the two groups. Sudden and unexpected death is generally attributed to heart disease. The lower rate of sudden death was unexpected.

ELITE II enrolled 3,152 patients over the age of 60 with mild heart failure (most of these patients were not hypertensive), and allocated them to be treated with either losartan (50 milligrams a day) or captopril (50 milligrams 3 times a day), and followed them for one and a half years. In this case there was no difference between the two groups in either mortality or the rates of hospitalization for heart failure. There were, however, fewer side effects in the losartan treated group. These results suggest that the apparent benefit from losartan in the earlier smaller study may have been due to chance.

Doctor’s comments

From what is known about ACE inhibitors and ARBs from other studies, there was no good reason to expect that the ARB (losartan) would result in less sudden deaths than an ACE inhibitor in the first pilot study. One of the reasons for doing the pilot study was to see if the ARB would cause any deterioration of kidney function in older people (it did not). In one sense the results of ELITE II were negative, in that it did not show any improvement in survival as a result of being treated with losartan, but on the other hand, it can also be said that the losartan-treated patients did just as well as the ACE inhibitor-treated group (better if you allow for the fewer side effects) and it has already been established that ACE inhibitors are better than many other types of blood pressure –lowering drugs at preventing death from heart failure, so it could be argued that losartan is an alternative.

Where it was published