Scientists at The University of Manchester have discovered a drug that is commonly used to treat erectile dysfunction could reverse heart failure symptoms.
Funded by The British Heart Foundation, the research looked at the effect of Tadalafil, which is similar to Viagra, finding it was able to slow down or even treat heart failure when tested on sheep.
While the experiment has not been conducted on humans yet, lead author Professor Andrew Trafford said the same impact is likely to occur as the physiology of sheep hearts are similar to those of humans.
Professor Trafford said: “The discovery is an important advance in a devastating condition which causes misery for thousands of people across the UK and beyond.”
The sheep involved in the study, which has been published in the journal Scientific Reports, were fitted with pacemakers that brought on heart failure before they were administered with Tadalafil.
After a short while, their breathlessness – caused by the heart’s inability to respond to adrenaline – stopped worsening, and actually started to reverse.
This is due to the drug blocking the Phosphodiesterase 5 (PDE5S) enzyme that regulates how the body responds to hormones, including adrenaline.
In the case of heart failure, Tadalafil was able to alter the chemical reactions so the heart could, once again, respond to adrenaline and force blood around the body when working harder.
Heart failure occurs when the heart becomes too weak to pump enough blood around the body that a human requires. As a result, a build-up of fluid occurs in the lungs, leading to swelling in the body and breathlessness.
Associate medical director at the British Heart Foundation Professor Metin Avkiran noted that erectile-dysfunction drugs were actually originally developed as potential treatments for heart disease. However, after revealing other side effects they became commonly used for men who suffer from poor erectile performance.
“We seem to have gone full-circle, with findings from recent studies suggesting that they may be effective in the treatment of some forms of heart disease – in this case, heart failure,” the professor stated.
He added there is an urgent need for this condition, which he labels “cruel and debilitating”. Despite affecting more than one million people in the UK, sufferers are only given a survival rate of five years once diagnosed.
The NHS notes there is currently no cure for heart failure, though its symptoms – including swollen ankles and legs, fast heart rate, dizziness, persistent cough, breathlessness and feeling tired – can be controlled. This can be done through making changes to diet and exercise regimes, quitting smoking, fitting devices in the chest to control the cardiac rhythm, or in some cases, a bypass operation or even a heart transplant.
“The evidence from this study – that a Viagra-like drug could reverse heart failure – should encourage further research in humans to determine if such drugs may help to save and improve lives,” Professor Avkiran commented.
While the results so far from the study are encouraging, Professor Trafford warned against heart disease patients treating themselves with Tadalafil.
He noted that despite being a “very safe drug with minimal side effects”, it is only suitable for those with systolic heart failure and could clash with other drugs the sufferer is taking.
If further studies prove Tadalafil is a viable treatment for heart failure, pharma packaging companies could find themselves busy getting the drug out to the people who need it urgently.