Aurora Cardiovascular Services Case of the Month
ACS Editorial Board
Jasbir S. Sra, MD
Andrew Boyle, MD
Tanvir Bajwa, MD
David C. Kress, MD
Bijoy K. Khandheria, MD
A. Jamil Tajik, MD
Steven Port, MD
Masood Akhtar, MD
Percutaneous Repair of Clinically Significant Mitral Regurgitation
Scott Weslow, M.D, Tanvir Bajwa, M.D.
Mitral regurgitation (MR) affects millions of Americans, and in its severe form, can lead to heart failure and poor long-term survival. Medical therapy with vasodilators and afterload reduction in an attempt to increase forward flow through the aortic valve, rather than backward flow through the mitral valve, has not proven to be significantly beneficial for patients with chronic MR. Severe insufficiency of the mitral valve is a mechanical problem, and requires a mechanical solution. Surgical repair or replacement of the mitral valve has been the only definitive therapy for this condition to date. A new percutaneous option for treating MR is the MitraClip® system (Abbott Laboratories, Abbott Park, IL). We present a patient with severe symptomatic MR who underwent mitral valve repair using the MitraClip at Aurora St. Luke's Medical Center (ASLMC) and experienced dramatic improvement in symptoms.
A 76-year-old male with severe ischemic cardiomyopathy, ejection fraction 20%-25%, and severe MR experienced significant functional decline, requiring multiple hospitalizations for decompensated heart failure. He endured months of NYHA functional class III-IV symptoms despite all attempts at optimal medical therapy. He was unable to consistently tolerate beta-blocker and ACE inhibitor due to symptomatic hypotension. His comorbidities include coronary artery disease with coronary artery bypass grafting in 1996 (redone in 1997), atrial fibrillation status post AV node ablation and biventricular pacemaker, moderate aortic valve insufficiency, moderate pulmonary hypertension, chronic obstructive pulmonary disease (COPD), infrarenal abdominal aortic aneurysm status post stent graft, peripheral-arterial-disease-status femoral bypass, bilateral carotid atherosclerosis, hypertension, dyslipidemia, anemia, thrombocytopenia, anxiety, and depression.
Given the patient's decreased functional status, recurrent heart failure, multiple comorbidities, high surgical risk, and moderate-severe central functional MR, he was entered into the Endovascular Valve Edge-to-Edge REpair STudy (EVEREST) II nonrandomized, high-risk registry for placement of the MitraClip device (see Discussion). This was performed in the ASLMC catheterization laboratory under transesophageal echocardiographic guidance. The procedure had no complications, and the patient received immediate relief of his heart failure symptoms. His pre- and post-procedure echo images are shown below (Figs. 1 and 2). The night following the procedure, he was able to lie flat for the first time in 3 years and was discharged on post-procedure day three. Subsequent follow-up clinic visits found him to be completely devoid of heart failure symptoms at rest and with mild exertion (NYHA functional class II).
The MitraClip device essentially clips together the central parts of the two mitral valve leaflets, creating a double orifice valve, and was designed after the Alfieri stitch, first used by Dr. Ottavio Alfieri for surgical repair of the mitral valve in 1995 (1). Accordingly, a prerequisite for use of the device is a central jet of MR.
There are two trials investigating the MitraClip system – EVEREST I (115 patients) and EVEREST II (279 patients) (2). EVEREST I was a nonrandomized feasibility study that showed the device to be safe and effective. EVEREST II randomized patients in a 2-to-1 fashion to either surgery or mitral clipping (3), but also included a nonrandomized registry group for patients who were not surgical candidates, as was the case with our patient. There were 37 centers involved, and all patients had either functional (27%) or degenerative (73%) MR (1). The final results of EVEREST II were presented at the American College of Cardiology 2010 Scientific Sessions and demonstrated noninferiority of mitral clipping to surgical repair/replacement at one year, similar improvement in quality of life, and fewer complications in the MitraClip group (3-5).
The MitraClip system has been approved for use in Europe since 2007, and while use in the United States has only been investigational, it should receive FDA approval in the near future. Patient selection is essential to the clinical success of the procedure, and there will always be patients whose best option is surgery. However, we now have a low-risk, minimally invasive tool to mechanically treat the pathology of mitral regurgitation and, in doing so, dramatically improve quality and possibly duration of life in patients whose previous therapeutic options ranged from few to none.
- Wood S. EVEREST II: Mitral-clip device noninferior to surgical repair or replacement.
- Block PC. The EVEREST trials: A new option for treatment of mitral regurgitation?
- Cadet J. ACC: MitraClip system may present alternative for non-surgical patients.
- Abbott's investigational MitraClip® system demonstrates strong safety results and improved clinical outcomes for common causes of leaky heart valves (Abbott Laboratories press release, May 25, 2010).
- Feldman T. Primary safety and efficacy end points of the EVEREST II randomized clinical trial. Presented at the American College of Cardiology Scientific Sessions, Atlanta, March 14, 2010.
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