Sildenafil, a popular medication used to treat erectile dysfunction, may increase the severity of abdominal aortic aneurysms (AAAs), according to new data published in the Journal of the American Heart Association.
Sildenafil, a phosphodiesterase 5 (PDE5) inhibitor, is most famously sold under the name Viagra. In addition to treating erectile dysfunction, it is also regularly prescribed for pulmonary hypertension.
The study's authors evaluated the effect of sildenafil on mice by inducing AAAs and then treating each mouse with the sildenafil or a placebo for a total of four weeks.
After those four weeks, the researchers noted that AAAs were significantly larger among mice given sildenafil—37% wider, in fact. In addition, the mice given sildenafil had almost 50% more elastin fiber degradation.
“Our study suggests that sildenafil aggravated the progression of AAAs, likely through disrupting the smooth muscle cells’ ability to contract and function properly,” corresponding author Chen Yan, PhD, a professor in the department of medicine at Aab Cardiovascular Institute at the University of Rochester School of Medicine and Dentistry, said in a prepared statement. “These findings may raise caution about prescribing PDE5 inhibitors like sildenafil for patients who have existing aortic aneurysmal lesions. Clinical studies and other types of animal models of abdominal aortic aneurysm may be warranted to study this further.”
"Caution may be appropriate in chronic usage of sildenafil-like medications among men with aneurysms or who are at highest risk for an aneurysm," added lead study investigator Chongyang Zhang, MS, a PhD candidate at Aab Cardiovascular Institute.
Read the full study here.