• Posted May 24, 2023

Large Study Supports Less Invasive Way to Treat 'Leaky' Heart Valves

When one of the heart's valves springs a big leak, that can spell big trouble.

The good news: The condition, known as degenerative mitral regurgitation (DMR), is treatable using a minimally invasive intervention known as TEER (transcatheter edge-to-edge repair), a procedure that involves the insertion of a small clip to enable proper valve closure and blood flow.

The better news? A new real-world analysis is the first to definitively conclude that the vast majority of patients who undergo the procedure do well afterwards.

That should reassure the more than 2 million Americans who have been diagnosed with DMR.

"Treatment was successful in nearly 9 out of every 10 patients in whom TEER was used to repair their mitral valve,"study lead author Dr. Raj Makkar said in a statement.

"These strong safety and efficacy outcomes were validated, despite the advanced age and significant co-morbidities [other health complications] of these patients,"added Makkar, vice president of cardiovascular innovation and intervention at Cedars-Sinai Medical Center in Los Angeles.

Makkar and his colleagues noted that the average age of the more than 19,000 patients tracked by the study team was about 82 years. All of the patients had been diagnosed with severe DMR.

According to the American Heart Association (AHA), when a major valve leak occurs what ends up happening is that every time the left heart chamber contracts, the blood that should then flow in just one direction -- from the heart ventricle through the aortic valve -- ends up flowing in two directions instead. As a result, the heart has to work harder than normal to pump the same amount of blood, potentially increasing pressure both in the left heart chamber and in the veins that lead from the heart to the lungs.

Beyond impeding lung function, if left untreated a severe mitral leakage can ultimately cause the heart to enlarge to such a degree that heart failure develops.

The condition is more common than some might think, noted Makkar, who pointed out that "almost 1 out of 10 persons above the age of 75 has a leaky valve."

For many such patients, open heart surgery is the common intervention.

But "there are lots of older patients who are not the best candidates for open heart surgery,"he cautioned.

Instead, many of those patients may fare better with a less invasive procedure such as TEER, in which "the mitral valve is repaired by placing a clip on the leaky portion of the mitral valve... Most patients go home in less than 24 hours, with low risk of in-hospital mortality."

Because the patients in the study ranged in age from 76 to 86, the investigators noted that many struggled with health complications beyond a leaky heart valve.

As a result, the study team divided the patient pool into three groups based on the risk that the patient would ultimately not survive the TEER procedure. About 10% were deemed to face low surgical risk, nearly 70% were classified as intermediate risk, and just over 20% were identified as high risk.

Information on TEER outcomes were gleaned from a database maintained by the Society of Thoracic Surgeons and the American College of Cardiology.

A successful TEER outcome was defined as resulting in a change in leak status from "severe"to "better-to-moderate,"without any narrowing of the leaky valve. Post-procedure death rates were also assessed at three points: while patients were still hospitalized, and both a month and a year post-procedure.

In the end, the investigators found just 2.7% of TEER patients died during the 30-day period.

And across all patient risk categories, TEER reduced valve leak severity among more than 95% of patients by the 30-day post-procedure mark.

"The procedure is getting many patients back to a more energetic life, and back to activities some haven't been able to do for years,"Makkar said.

Still, his team also observed that by the same 30-day mark a far lower number of patients (67%) ended up with what investigators characterized as a leak status amounting to "mild or less."

That is concerning, said Dr. Gregg Fonarow, director of the Ahmanson-UCLA Cardiomyopathy Center and co-director of the UCLA Preventative Cardiology Program in Los Angeles.

Noting that "there have been relatively few analyses of this procedure in U.S. clinical practice,"Fonarow acknowledged that Makkar's study suggests that for moderate-to-severe valve leak patients, the procedure "appears to be a reasonable treatment option."

But at the same time, he suggested that "there remains further opportunities to improve upon this procedure,"given the lower number of patients who achieved a "mild"leak status following TEER.

Fonarow noted that a large randomized trial comparing the relative benefits of other surgery options verses TEER is already underway.

The findings were published May 23 in the Journal of the American Medical Association.

More information

There's more on leaky mitral valves at the American Heart Association.

SOURCES: Raj Makkar, MD, associate director, Smidt Heart Institute, and vice president, cardiovascular innovation and intervention, Cedars-Sinai Medical Center, Los Angeles; Gregg Fonarow, MD, director, Ahmanson-UCLA Cardiomyopathy Center, co-director, UCLA Preventative Cardiology Program, and co-chief, division of cardiology, University of California, Los Angeles; Journal of the American Medical Association, May 23, 2023