Mitral Regurgitation in Transcatheter Aortic Valve Replacement

Abstract

Transcatheter aortic valve replacement (TAVR) has emerged as an alternative treatment for patients with symptomatic aortic stenosis (AS) who are at an unacceptably high risk for conventional surgical aortic valve replacement (AVR).1,2 Approximately 60 000 patients worldwide have undergone TAVR in the 11 years since it was introduced.3 Although good procedural success and favorable clinical outcomes have been reported,4,5 issues remain regarding the best patient selection for the procedure. Risk calculators commonly used to estimate the risk of valvular surgery, such as the logistic EuroSCORE and the Society of Thoracic Surgeons model, are not considered accurate in patients undergoing TAVR because they do not account for all clinical characteristics that may significantly affect procedural and postprocedural mortality. The current selection criteria are based on those used in randomized trials, and, in conjunction with the clinical evaluation, echocardiography is a mainstay in the assessment of candidates for this procedure. Beyond the clinical and anatomic exclusion criteria, severe pulmonary hypertension with right ventricular dysfunction, very severe left ventricular (LV) systolic dysfunction (ejection fraction <20%), and severe mitral regurgitation (MR) are among the echocardiographic exclusions.6 Moreover, each of the commercially available prosthesis manufacturers presents its own recommendations for the procedure, with the CoreValve being more restrictive with respect to concomitant valvular disease. Article see p 2145 Nevertheless, the criteria for patient selection are still open to debate and are not considered binding. As a consequence, patients found in TAVR registries often have characteristics that go beyond the recommended criteria, and this procedure is being considered in a wider array of patients with off-label indications. TAVR in patients with significant MR is one example, and several large series have reported up to 48% of patients with moderate or severe MR.7,8 Nevertheless, until recently, the …