COAPT Evaluates Abbott's MitraClip to Treat Secondary Mitral Valve Regurgitation in Heart Failure Patients
September 23, 2018—The Cardiovascular Research Foundation (CRF) announced that findings from the randomized COAPT trial were presented by Gregg W. Stone, MD, at TCT 2018, the 30th annual Transcatheter Cardiovascular Therapeutics scientific symposium, which is sponsored by CRF and held September 21–25 in San Diego, California. The findings were simultaneously published online by Dr. Stone et al in The New England Journal of Medicine.
The COAPT data demonstrated that patients with heart failure and secondary mitral regurgitation (MR) who remained symptomatic despite maximally tolerated medical therapy demonstrated reduced rates of hospitalizations and death, as well as improved quality-of-life and functional capacity after being treated with the transcatheter MitraClip device (Abbott Structural Heart). These findings have the potential to significantly change current clinical practice, noted CRF.
In the CRF announcement, Dr. Stone commented, “The prognosis for heart failure patients who develop severe secondary mitral regurgitation is poor with limited treatment options. There is a great need to help improve outcomes for these very sick patients.” Dr. Stone is Professor of Medicine at Columbia University Irving Medical Center and Director of Cardiovascular Research and Education at the Center for Interventional Vascular Therapy at NewYork-Presbyterian/Columbia University Irving Medical Center in New York, New York.
The background of the study is that it is unknown if the MitraClip device is useful for secondary MR. The MitraClip is currently approved in the United States for use in primary MR.
According to CRF, COAPT was a randomized, parallel-controlled, open-label, multicenter trial evaluating transcatheter mitral valve repair with the MitraClip device in symptomatic heart failure patients with moderate-to-severe or severe secondary MR. A total of 614 patients were randomized at 78 centers in the United States and Canada. A total of 302 patients were assigned to the device and guideline-directed medical therapy (GDMT) in the device group and 312 patients were assigned to GDMT alone in the control group.
The primary effectiveness endpoint was the annualized rate of all heart failure hospitalizations through 24 months and the primary safety endpoint was freedom from device-related complications at 12 months.
The investigators found that after 2 years, there were total heart failure hospitalizations in 160 patients who received the mitral clip versus 283 patients for the control group. The annualized rates of heart failure hospitalization were 35.8% per patient-year in the device group versus 67.9% per patient-year in the control group (hazard ratio [HR], 0.53; 95% confidence interval [CI], 0.4–0.7; P < .001).
The 12-month freedom from device-related complications was 96.6% (lower 95% confidence limit, 94.8%), which exceeded the performance goal of 88.0% for the primary safety endpoint (P < .001).
All-cause mortality at 24 months with the device was 29.1% compared to 46.1% in the control group (HR, 0.62; 95% CI, 0.46–0.82; P < .001).
In addition to the reductions in hospitalizations and mortality, device treatment also resulted in the following improvements in quality-of-life measures and functional capacity:
- Kansas City Cardiomyopathy Questionnaire overall summary score changed from baseline to 12 months after transcatheter mitral repair of a mean 12.5-point increase compared to a mean 3.6-point reduction in the GDMT-alone group.
- Exercise capacity as measured by 6-minute walk distance decreased during 12-month follow-up by approximately 60 m with GDMT alone but remained unchanged after transcatheter mitral repair.
- NYHA heart failure classification improved to a greater degree with the transcatheter device compared with GDMT alone at all follow-up times.
Also, patients treated with the MitraClip also had a lower incidence of heart transplant or left ventricular assist device use (4.4% for the device group vs 9.5% for the control group).
Dr. Stone concluded in the CRF press release, “At 2 years, transcatheter mitral valve repair with the MitraClip device was found to be safe and effective. It substantially reduced the rate of hospitalizations and mortality, while improving quality-of-life and functional capacity. This procedure gives cardiologists an important option for high-risk heart failure patients with secondary MR who remain symptomatic despite optimal medical therapy.”