First mitral procedures show transapical implantation is feasible

Transcatheter mitral valve implantation looks like the next frontier in treatments for patients who are at high risk for surgical valve repair or replacement. In a first-in-man report, physicians demonstrated that a transapical approach is technically feasible and potentially safe.

Anson Cheung, MD, of the cardiothoracic surgery division at St. Paul’s Hospital in Vancouver, and colleagues performed two transapical mitral valve implantations using the Tiara system (Neovasc). The catheter-based system was specifically designed as a treatment for mitral regurgitation with a valve that conforms to the D-shaped mitral annulus. They published their results in the Oct. 28 issue of the Journal of the American College of Cardiology.

The two patients qualified for compassionate treatment because they were too high risk for surgery and not appropriate candidates for percutaneous mitral valve repair. The first patient, a 73-year-old man, had severe ischemic cardiomyopathy, functional mitral regurgitation, New York Heart Association (NYHA) class IV heart failure and left ventricular ejection fraction (LVEF) of 15 percent to 20 percent. The second patient, a 61-year-old woman, had ischemic cardiomyopathy, severe functional mitral regurgitation, NYHA class III to IV heart failure and LVEF of 25 percent.

Both patients underwent cardiac-gated multislice CT imaging in preparation of the procedure, which occurred in a hybrid operating room. After implantation, they had no significant mitral regurgitation on angiograms.

The first patient required cardiopulmonary resuscitation on day 21 after the procedure due to a hypotensive episode following hemodialysis. He also developed pneumonia and sepsis. He was discharged at five weeks and readmitted for heart failure.

“Despite a well-functioning prosthesis and elimination of MR [mitral regurgitation], Patient #1 experienced refractory end-stage cardiac failure,” they wrote. “Palliative care was initiated, and the patient died on day 69 post-implant.”

The hospital discharged the second patient five days after implantation. At two months, she showed “significant improvement,” with functional NYHA class II symptoms.

Valve function was normal with no device-related complications in both patients at four days, one month and two months after implantations, as assessed by echocardiograms. “The procedure was performed without hemodynamic compromise, was minimally invasive, and off-pump,” they wrote.

Based on this demonstration of its feasibility, mitral valve implantation “may present another chapter in the evolution in the treatment of valvular heart disease.”