ESC: Abbott MitraClip study shows gains in functional-yet-leaky heart valves

A study from Abbott found that employing its cardiac valve repair implant during earlier phases of heart failure—when a patient’s leaky mitral valve is still considered to be functional—could lead to fewer related hospitalizations while improving health status and quality of life.

The trial’s long-awaited results were once expected to settle some of the differences between two previous examinations of the company’s MitraClip approach: one in 2018 that found no difference between death rates or hospitalizations within one year, when comparing the heart repair device to standard medical therapy, and a subsequent study that demonstrated lower rates of both out to 24 months.

The latest data, taken from the RESHAPE-HF2 study, largely included patients with moderate to severe functional mitral regurgitation, versus the previous two trials—dubbed MITRA-FR and COAPT, respectively—which enrolled people in comparatively more severe categories of the condition overall.

Functional mitral regurgitation arises not from issues with the valve itself but as a result of problems with the heart’s surrounding left ventricle and atrium that keep the valve’s leaflets from properly closing. If untreated, the symptomatic condition can worsen over time; however, care guidelines currently only recommend intervening if the patient requires a separate surgical procedure at the same time.

RESHAPE-HF2’s results were published in The New England Journal of Medicine and are set to be presented this weekend during the annual meeting of the European Society of Cardiology, held in London.

The study randomized 505 patients to receive either the MitraClip plus the standard of care or simply the current recommended drug therapies. The minimally invasive procedure pinches together a portion of the mitral valve’s leaflets to help it close more completely and halt the backflow of blood through the heart.

After two years, significantly fewer patients in the MitraClip arm either died or reported their first or subsequent hospitalizations due to heart failure versus the control group—described by researchers as 37.0 events per 100 patient-years, compared to a rate of 58.9. When counting only hospitalizations, the study pegged the 24-month relative difference between the two sides of the study at 41%.

In addition, during the first year patient-reported measures of quality of life increased by an average difference of nearly 11 points, as recorded on the Kansas City Cardiomyopathy Questionnaire.

Researchers noted that, while RESHAPE-HF2 was not designed to show differences in mortality alone, the study did not demonstrate lower rates of death from any cause between the two arms, and attributed that in part to cases of less advanced heart failure.

The investigators also pointed out that the control group in RESHAPE-HF2 saw fewer overall deaths and hospitalizations compared to the control in the COAPT study, which suggested the patients enrolled had less severe disease as well.