Helping Little Hearts Pump Better

Viagra use shows improvement in pumping ability for young people with heart defects

(RxWiki News) Viagra may not just be for dads anymore. Drugs can often be used for multiple unrelated purposes, and it turns out sildenafil, the generic version of Viagra, might help children and young adults with heart defects.

A recent small study has found that the drug helped improve the functioning of the heart in a group of children who had a specific type of congenital heart defect.

Sildenafil is already used to treat high blood pressure in the lungs, and some evidence has shown it might be able to treat adults with heart failure.

"Talk to your child's cardiologist about emerging heart defect treatments."

David Goldberg, MD, a pediatric cardiologist at The Children's Hospital of Philadelphia, led the study as part of a larger phase 2 clinical trial called Sildenafil After the Fontan Operation (SAFO).

This smaller study included 27 children and young adults - an average age of 15 - with a heart problem called single ventricle heart disease palliation.

This defect occurs when one of the heart's two ventricles has not fully developed, so the heart has a much harder time pumping blood to the body. (Normally, the right ventricle pumps blood to the lungs and the left pumps it to the rest of the body.)

Each of the participants had already received a surgery in early childhood called a Fontan operation, the last of three surgeries typically given to people who have this single-ventricle defect.

The Fontan procedure redirects blood circulation so that blood coming from the rest of the body gets sent directly to the lungs to get oxygenated instead of going through the heart, thereby freeing up the working ventricle of the heart to pump more blood to the rest of the body.

The 27 participants received either Sildenafil (Viagra) or a placebo pill for six weeks. Then the participants took no medication for six weeks before switching to the opposite treatment for six weeks. In other words, those who took Sildenafil before now took the placebo and vice versa.

The participants did not know when they were taking the real drug and when they were taking the placebo, and neither did the person who gave them the medication.

Goldberg's team used echocardiograms, which are ultrasounds for the heart, to measure how well the heart pumped blood in these participants. They found that taking Sildenafil led to significant improvements in the pumping ability of the ventricles in these children and young adults.

Because researchers don't fully understand the biological system that impacts how ventricles operate, they cannot know for certain how Sildenafil works in these patients.

Past studies, however, have provided some clues, and Goldberg said that more studies should be conducted to find out if the improvement in the heart's pumping performance can last more than the short-term and whether it can improve the quality of life for these patients.

Although Fontan procedures can improve mortality and heart circulation in people with an underdeveloped single-ventricle, people with this defect still have long-term problems and a risk of early death.

"If Sildenafil is safe over the medium and long-term, and if it produces durable functional improvements, patients with single-ventricle heart disease could have their first effective long-term treatment," Goldberg said.

The study appeared online in February in the journal Pediatric Cardiology. The research was funded by grants from the Mark H. and Blache M. Harrington Foundation, from Big Hearts to Little Hearts and from the National Institutes of Health.

Review Date: 
May 8, 2012