Viagra good for the heart

A long-term daily treatment with Viagra can provide protection for the heart at different stages of heart disease with few side effects, the researchers reported.

"We found that this main ingredient in Viagra can be used as an effective, safe treatment for several patients with heart disease. Large clinical trials are now urgently needed to build on these encouraging findings," claimed lead study author Andrea Isidori from the Sapienza University of Rome, Italy.

Phosphodiesterase-5 inhibitor (PDE5i) is the main ingredient in Viagra and other drugs commonly used to treat erectile dysfunction.

The inhibitor blocks the enzyme PDE5, which prevents relaxation of smooth muscle tissue.

For the study, scientists carried out a meta-analysis of randomised controlled trials by searching for articles published between January 2004 and May 2014 to test the effectiveness of PDE5i in providing cardiac protection.

They identified 24 suitable trials involving 1622 patients from mixed populations who were treated with PDE5i or a placebo.

For the first time, they conducted a parallel analysis of the effects of the inhibitor on the size and shape of the heart and its performance.

The analysis shows that PDE5i prevented the heart from increasing in size and changing shape in patients suffering from left ventricular hypertrophy - a condition which causes thickening of the muscles in the left ventricle.

The inhibitor also improved heart performance in all patients with other heart conditions with no negative effect on the patients' blood pressure.

"The inhibitor could be reasonably administered to men who suffer from heart muscle thickening and early-stage heart failure," the authors concluded.