We welcome this study but would suggest that more research needs to be done

British Heart Foundation spokeswoman

But doctors at the Phillips University of Marburg in Germany have found ACE Inhibitors can work to break down this tissue and restore the normal function of the heart.

They enrolled 35 volunteers in their study. Each of these patients had high blood pressure, which is one of the symptoms of heart failure.

Each patient underwent an operation to remove a sample of collagen from their heart.

They were prescribed either an ACE Inhibitor or a diuretic, an older anti-blood pressure drug for six months.

They then underwent the operation again and had another sample removed from their heart.

This enabled the doctors to measure the levels of collagen in the heart at the beginning and end of the study.

They found that levels of collagen had fallen in those who had taken ACE Inhibitors.

Restored

Professor Christian Brilla, from the Philipps University of Marburg and head of the study, said: "We took tissue samples directly from the heart which showed, for the first time, a significant improvement."

She added: "At the beginning of the study patients had stiff and damaged hearts but after treatment, their hearts were restored towards normal."

The British Heart Foundation welcomed the study. But a spokeswoman said there was still no cure for heart failure.

"Heart failure is an increasing problem. There isn't a cure for it but we have found that ace inhibitors can help.

"The problem though is that it is not suitable for everyone and not all patients want to take it. It probably is underused.

"We welcome this study but would suggest that more research needs to be done."

The study was published in the American Heart Association's journal Circulation.