Washington, Nov 19 (IANS) Sildenafil, a drug for treating impotence, also perks up cardiac function in kids and young adults with single-ventricle congenital heart disease post Fontan surgery that redirects deoxygenated blood directly to the pulmonary arteries, bypassing the heart.

Single-ventricle defects are a collection of cardiac malformations that impair the heart's ability to pump blood.

'The enhanced heart performance may improve exercise performance and quality of life in these children and young adults,' said David J. Goldberg, paediatric cardiologist at The Children's Hospital of Philadelphia, who led the study.

Researchers hypothesised that Sildenafil may help cardiac performance by directly improving the squeeze of the heart muscle and by allowing for better filling of the heart.

Researchers randomised children and young adults who had undergone the Fontan operation to receive placebo or Sildenafil three times a day for six weeks.

Subsequently, subjects were switched to the opposite treatment course. The researchers found significant improvement in heart performance during treatment with Sildenafil, said a Children's Hospital release.

He presented the abstract on Nov 17 at the American Heart Association Scientific Sessions in Orlando.