Just over a decade ago, an interventional cardiology team led by Richard Smalling, MD, PhD, at McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), knew it had a problem as results of a dye test lit up the monitor.

A patient with a thickening heart muscle was down to her last hope for easing the shortness of breath and debilitating fatigue that came with the rare condition. She wasn’t a candidate for open heart surgery, and the other option – alcohol septal ablation (ASA) – had just been ruled out because of the anatomy of her heart.

But Smalling decided to try something different – the deployment of coils into blood vessels feeding the thickened muscle that impeded blood flow through the heart.

It worked.

The positive safety and efficacy results of a 10–year clinical trial launched after that first procedure were recently published in the journal Catheterizations and Cardiovascular Interventions. The procedures took place at Memorial Hermann Heart & Vascular Institute–Texas Medical Center (HVI).

Called septal coil embolization, the procedure is for a condition called hypertrophic obstructive cardiomyopathy (HOCM), which occurs when the heart muscle thickens and impedes the flow of blood out of the heart’s left ventricle. About 1 in 500 adults have it.

To gauge the safety and effectiveness of coil embolization, Smalling’s team studied 24 patients who had the procedure between 2005 and 2015. Twenty–two of the patients experienced significant improvement.

Smalling said the benefits of coil embolization over ASA include fewer complications, shorter hospital stay and less pain during the procedure. Only about 5 percent of coil embolization patients required a pacemaker in comparison to up to 30 percent with ASA.

Smalling, the study’s senior author and chief of interventional cardiology at McGovern Medical School and HVI, said the next step will be a clinical trial comparing coil embolization to ASA.