Mitral Regurgitation After Transcatheter Aortic Valve Replacement: Prognosis, Imaging Predictors, and Potential Management.

OBJECTIVES: This study sought to analyze the clinical impact of the degree and improvement of mitral regurgitation in TAVR recipients, validate the main imaging determinants of this improvement, and assess the potential candidates for double valve repair with percutaneous techniques. BACKGROUND: Many patients with severe aortic stenosis present with concomitant mitral regurgitation (MR). Cardiac imaging plays a key role in identifying prognostic factors of MR persistence after transcatheter aortic valve replacement (TAVR) and for planning its treatment. METHODS: A total of 1,110 patients with severe aortic stenosis from 6 centers who underwent TAVR were included. In-hospital to 6-month follow-up clinical outcomes according to the degree of baseline MR were evaluated. Off-line analysis of echocardiographic and multidetector computed tomography images was performed to determine predictors of improvement, clinical outcomes, and potential percutaneous alternatives to treat persistent MR. RESULTS: Compared with patients without significant pre-TAVR MR, 177 patients (16%) presented with significant pre-TAVR MR, experiencing a 3-fold increase in 6-month mortality (35.0% vs. 10.2%; p < 0.001). After TAVR, the degree of MR improved in 60% of them. A mitral annular diameter of >35.5 mm (odds ratio: 9.0; 95% confidence interval: 3.2 to 25.3; p < 0.001) and calcification of the mitral apparatus by multidetector computed tomography (odds ratio: 11.2; 95% confidence interval: 4.03 to 31.3; p < 0.001) were independent predictors of persistent MR. At least 14 patients (1.3% of the entire cohort, 13.1% of patients with persistent MR) met criteria for percutaneous mitral repair with either MitraClip (9.3%) or a balloon-expandable valve (3.8%). CONCLUSIONS: Significant MR is not uncommon in TAVR recipients and associates with greater mortality. In more than one-half of patients, the degree of MR improves after TAVR, which can be predicted by characterizing the mitral apparatus with multidetector computed tomography. According to standardized imaging criteria, at least 1 in 10 patients whose MR persists after TAVR could benefit from percutaneous mitral procedures, and even more could be treated with MitraClip after dedicated pre-imaging evaluation.

Approaches to the management of functional tricuspid regurgitation.

Functional tricuspid regurgitation (FTR) is an acquired valvular abnormality that is most frequently encountered during the evaluation and operative management of left-sided heart failure and left heart valve disease. Observational studies have demonstrated that uncorrected significant FTR during mitral valve surgery can result in inferior early and late outcomes due to progression of FTR and underlying right heart failure. The 2012 ESC/EACTS and 2014 ACC/AHA guidelines strongly encourage the surgical correction of greater than mild tricuspid regurgitation or tricuspid annular dilation greater than 4 cm in patients undergoing left-sided valve surgery. Prospective randomized trials are needed to bolster the evidence behind the current recommendations. Percutaneous therapies in development may eventually result in less invasive options for treating FTR.

Transcatheter aortic valve replacement in elderly patients.

Aortic stenosis is the most common native valve disease, affecting up to 5% of the elderly population. Surgical aortic valve replacement reduces symptoms and improves survival, and is the definitive therapy in patients with symptomatic severe aortic stenosis. However, despite the good results of classic surgery, risk is markedly increased in elderly patients with co-morbidities. Transcatheter aortic valve replacement (TAVR) allows implantation of a prosthetic heart valve within the diseased native aortic valve without the need for open heart surgery and cardiopulmonary bypass, offering a new therapeutic option to elderly patients considered at high surgical risk or with contraindications to surgery. To date, several multicenter registries and a randomized trial have confirmed the safety and efficacy of TAVR in those patients. In this chapter, we review the background and clinical applications of TAVR in elderly patients.