Medical Versus Surgical Management of Moderate Mitral Regurgitation Following Percutaneous Coronary Intervention

Medical Versus Surgical Management of Moderate Mitral Regurgitation Following Percutaneous Coronary Intervention

Medical Versus Surgical Management of Patients With Moderate Mitral Regurgitation Following Percutaneous Coronary Intervention for Myocardial Infarction: A Pilot Prospective Randomized Trial

The pilot prospective randomized trial is designed to determine the safety and feasibility of enrolling patients to surgically correct residual Mitral Regurgitation (MR) following Percutaneous Coronary Intervention (PCI) for Myocardial Infarction (MI) verses ongoing medical management of MR. The investigators hypothesize that if moderate MR is corrected in this patient subset, the patients will have improved outcomes as measured by decreased number of major adverse cardiac events, including death, congestive heart failure requiring hospitalization, atrial fibrillation, deterioration of New York Heart Association (NYHA) functional status and improved quality of life.

Mitral regurgitation (MR) is a frequent complication of myocardial infarction. Ischemic MR portends a poor prognosis on long term follow up. This pilot prospective randomized trial is a safety and feasibility trial to evaluate mitral valve repair versus surgical management in patients with residual MR after primary percutaneous coronary intervention (PCI). Patients will be screened for possible inclusion to identify those that have first MI treated with primary PCI. Patients with moderate MR at 6 or more weeks following first primary PCI will be randomized to continued medical management versus surgical mitral valve repair. Patients with previous or subsequent coronary artery bypass surgery and patients with severe ventricular dysfunction will be excluded. Patients will be followed for one year from the time of randomization. The safety and feasibility data will be used to design a large trial powered to detect a difference in mortality between treatment arms. Results of this study could lead to a radical change in the treatment paradigm for patients with ischemic MR following PCI for acute MI. In addition, insight gained from this study could advance our understanding of the interrelationship between LV remodeling and MR and shed some light into the mechanism of ventricular function deterioration following MI. Moreover, it may provide a framework for the development of further recommendations with respect to the indications for surgical intervention in this patient population.

Non-invasive transesophageal echocardiography will be performed on all study volunteers to determine if the individual has mitral regurgitation and, if so, to what degree. Mitral valve repair will be performed with mitral valve annuloplasty via median sternotomy, utilizing cardiopulmonary bypass and moderate hypothermia.

Clinical observation will be continued without surgery. Non-invasive transesophageal echocardiography will be performed on all study volunteers to determine if the individual has mitral regurgitation and, if so, to what degree.

Mitral valve repair will be performed via median sternotomy, utilizing cardiopulmonary bypass and moderate hypothermia. The mitral valve will be approached through a left atrial incision. Following inspection of the valve, mitral valve annuloplasty will be accomplished with a complete semi-rigid annuloplasty ring. Additional techniques to address residual regurgitation will be at the discretion of the surgeon. The left atriotomy will then be closed and the patient weaned off and separated from the cardiopulmonary bypass. Intraoperative transesophageal echocardiography will be performed on all study volunteers.

Patient survival will be prospectively documented for all study subjects from recruitment through one year. A stopping rule for the surgical arm is a pre-specified cut-off of 5% based on the method proposed by Kramar and Bascoul-Mollevi in "Early Stopping Rules in Clinical Trials Based on Sequential Monitoring of Serious Adverse Events" [39]. A data and safety monitoring board (DSMB) that includes five independent investigators and a statistician has been established to conduct ongoing study review to maintain safety of all participants.

Hospitalization for congestive heart failure will be prospectively documented for all study subjects from recruitment through one year.

Transthoracic echocardiogram will be obtained to assess the presence and or severity of mitral regurgiation.

Inclusion Criteria: Patients who have undergone PCI for first acute MI (index MI) since 7/1/09 at MMC and STJ documented moderate mitral regurgitation on follow up echocardiography six or more weeks after PCI procedure English speaking Exclusion Criteria: CABG after PCI for acute MI History of previous MI prior to index MI History of previous PCI or CABG prior to index PCI EF <30 % on the echocardiogram at 6 weeks after PCI for MI

Vassileva CM, Boley T, Markwell S, Hazelrigg S. Meta-analysis of short-term and long-term survival following repair versus replacement for ischemic mitral regurgitation. Eur J Cardiothorac Surg. 2011 Mar;39(3):295-303. doi: 10.1016/j.ejcts.2010.06.034. Epub 2010 Aug 19.