A study published in the New England Journal of Medicine found that compared to mitral valve repair, mitral valve replacement results in a lower rate of heart failure and fewer hospitalizations for cardiovascular complications at two years after surgery.
The team of researchers tracked 251 ischemic mitral regurgitation patients following implantation of either a repair or replacement device. After two years, they were evaluated for occurrence of stroke, subsequent mitral valve surgery, heart failure, rehospitalization, recurrent regurgitation, quality of life and mortality, according to New York City's Montefiore Medical Center, which participated in the study.
"Building on the one-year clinical data reported in 2014, we concluded that while there was no difference in the rate of survival for valve replacement or repair, mitral valve replacement did prove to be a more durable option for the treatment of severe ischemic regurgitation," said the study's senior author, Dr. Michael Acker, a professor of surgery at the University of Pennsylvania's Perelman School of Medicine, in a statement. "Recurrence of MR (mitral regurgitation) led to increased cardiovascular readmissions and more heart failure adverse events when compared to replacement. Until we can reliably predict the patients who will recur after repair, replacement is a more reliable treatment for patients with severe ischemic mitral regurgitation. Additional research is needed to better predict the patients who can be repaired without recurrence."
In addition to the clinical implications, the study has potential business implications as well, especially to the burgeoning field of transcatheter mitral valve devices. The NEJM study analyzed mitral valve implants that were surgically implanted, for there are no approved procedurally implanted transcatheter replacement devices, and only one FDA-approved for repair.
Medtronic ($MDT), Edwards ($EW) and Abbott ($ABT) have dropped a combined $100 million on the transcatheter mitral valve replacement market in recent months, in the hopes of a repeat of the clinical and financial success of TAVRs, or transcatheter devices that replacement the aortic valve without the complications of open heart surgery, which is often too risky in frail patients.
With the exception of HeartWare ($HTWR), which is attempting to buy Israel's Valtech Cardio, the transcatheter replacement market has not seen any M&A activity of late.
Additional studies will be needed to determine if the NEJM findings related to surgically implanted implants extend to transcatheter ones that installing by inserting a delivery catheter into the heart. And it's certainly possible that both transcatheter repair and replacement end up coexisting side by side.
At the TCT conference in San Francisco, Harpoon Medical reported patients in a feasibility study of its investigational minimally invasive mitral valve repair technology experienced a reduction or elimination of mitral valve regurgitation, but it was used to treat degenerative mitral regurgitation patients.