Trends in Utilization of Surgical and Transcatheter Mitral Valve Repair in the United States^⋆⋆

Degenerative mitral valve disease (myxomatous degeneration or fibroelastic deficiency) is the most common indication for surgical referral to treat mitral regurgitation. Mitral valve repair is the procedure of choice whenever feasible and when the results are expected to be durable. Posterior leaflet prolapse is the commonest lesion, found in up to two-thirds of patients. It is the easiest to repair, particularly when limited to one segment. In these cases, rates of repairability and procedural success approach 100%, and there is now ample evidence that the immediate and long-term results are better than those of valve replacement. Notably, minimally invasive valvular procedures, surgical or interventional, have attracted increasing interest in the last decade. When performed by experienced groups, mitral valve repair is unrivaled irrespective of the severity of lesions, from simple to complex, which leaflets are involved, and the type of degenerative involvement (myxomatous or fibroelastic). Its results should be viewed as the benchmark for other present and future technologies. By contrast, percutaneous mitral valve repair is still in its infancy and its results so far fall short of those of surgical repair. Nevertheless, continued investment in transcatheter procedures is of great importance to enable development and improved accessibility, particularly for patients who are considered unsuitable for surgery. In this review, we analyze the current status of management of degenerative mitral valve disease, discussing mitral valve anatomy and pathology, indications for intervention, and current surgical and transcatheter mitral valve procedures and results.

A doença valvar mitral degenerativa – deficiência mixomatosa ou fibroelástica – é a indicação mais comum de referência cirúrgica para tratamento da regurgitação mitral. A plastia da válvula mitral é o procedimento de escolha sempre que possível e os resultados são duradouros. O prolapso do folheto posterior é a lesão mais comum, encontrada em cerca de dois terços dos pacientes. É mais fácil de reparar, principalmente quando limitado a um segmento. Nesses casos, as taxas de reparabilidade e de sucesso aproximam-se dos 100% e agora há ampla evidência de que os resultados imediatos e a longo prazo são melhores do que os da substituição valvular. Os procedimentos valvares minimamente invasivos, cirúrgicos ou de intervenção, têm ganhado crescente interesse na última década. Quando realizada por grupos experientes, a plastia da valva mitral não tem rival, independentemente da gravidade das lesões, das simples às complexas, de quais os folhetos envolvidos e do tipo de patologia degenerativa (deficiência mixomatosa versus fibroelástica). Os resultados devem ser usados como referência para outras tecnologias presentes e futuras. Por outro lado, o tratamento percutâneo da válvula mitral ainda é incipiente e os resultados, até ao momento, ficam aquém dos da correção cirúrgica. No entanto, o investimento contínuo em procedimentos transcateter é de extrema importância para possibilitar a evolução e acessibilidade aos pacientes, principalmente àqueles aos quais é recusada a cirurgia. Nesta revisão, analisamos o estado atual do tratamento da doença degenerativa da válvula mitral, discutindo a anatomia e patologia valvular, as indicações para a intervenção, os procedimentos e resultados cirúrgicos e transcateter atuais.

Transcatheter mitral valve repair (TMVR) utilization has increased significantly in the United States over the last years. Yet, a risk-prediction tool for adverse events has not been developed. We aimed to generate a machine-learning-based algorithm to predict in-hospital mortality after TMVR.

Patients who underwent TMVR from 2012 through 2015 were identified using the National Inpatient Sample database. The study population was randomly divided into a training set (n = 636) and a testing set (n = 213). Prediction models for in-hospital mortality were obtained using five supervised machine-learning classifiers.

A total of 849 TMVRs were analyzed in our study. The overall in-hospital mortality was 3.1%. A naïve Bayes (NB) model had the best discrimination for fifteen variables, with an area under the receiver-operating curve (AUC) of 0.83 (95% CI, 0.80–0.87), compared to 0.77 for logistic regression (95% CI, 0.58–0.95), 0.73 for an artificial neural network (95% CI, 0.55–0.91), and 0.67 for both a random forest and a support-vector machine (95% CI, 0.47–0.87). History of coronary artery disease, of chronic kidney disease, and smoking were the three most significant predictors of in-hospital mortality.

We developed a robust machine-learning-derived model to predict in-hospital mortality in patients undergoing TMVR. This model is promising for decision-making and deserves further clinical validation.

In the era of emerging options for mitral valvular intervention, we sought to characterize the relative utilization, outcomes, and posthospital dispositions of patients referred for transcatheter mitral valve repair (TMVRepair) and surgical mitral valve procedures (SMVP), by cancer-status. Leveraging the National Inpatient Sample, a representative national dataset, ICD-9 codes for all adults >18 years with co-morbid mitral regurgitation, and cancer without metastatic disease admitted from 2003 to 2015 were queried. TMVRepair was performed in 700 hospitalizations from 2012 to 2015, whereas SMVP was utilized during 12,863 hospitalizations from 2003 to 2015. During follow-up, we observed a proportional increase in TMVRepair utilization among cancer patients (vs noncancer), particularly in 2015 (14.2% vs 8.2%, p <0.0001). There was no difference in in-hospital mortality (1.4% vs 1.8%, p = 0.71), ischemic stroke (0.7% vs 0.6%, p = 0.97), major bleeding (8.6% vs 10.9%, p = 0.36), and home discharge (62.1% vs 65.7%, p = 0.45) by cancer-status among patients who underwent TMVRepair; but, cost of care was increased ($52,325 vs $48,832, p <0.0001). Similarly, there was no difference in in-hospital mortality (3.1% vs 3.4%, p = 0.36), ischemic stroke (2.6% vs 3.1%, p = 0.16) as well as the cost-of-care ($58,106 vs $58,844, p = 0.49) among those who underwent SMVP across the same period; but, cancer was associated with increased major bleeding (34.9% vs 30.5%, p <0.0001), and lower likelihood of home discharge (32.8% vs 38.6%, p <0.0001). In conclusion, TMVRepair and SMVP were associated with comparable in-hospital mortality and outcomes in cancer versus noncancer patients. However, cancer patients treated with SMVP experienced more frequent bleeding related complications compared with noncancer patients.