Catheter Management of Mitral Stenosis

Mitral stenosis is a progressive valvular disorder that results in left atrial (LA) enlargement, atrial fibrillation, and heart failure. Despite advances in modern medicine, rheumatic heart disease remains the most common cause of mitral stenosis, especially in low- and middle-income countries. Rheumatic mitral stenosis usually presents in patients aged between 20 and 40 years, about 10 to 15 years after the onset of rheumatic fever. In the United States, mitral stenosis secondary to rheumatic heart disease most commonly presents in the immigrant population and those with limited access to healthcare facilities. Calcific degenerative mitral valve stenosis is another cause of mitral stenosis, but it is far less common and typically seen in older adults. Patients with symptomatic mitral stenosis usually present with symptoms of heart failure, atrial fibrillation, or thromboembolism. Risk factors for rheumatic mitral stenosis include a history of rheumatic fever and a previously untreated streptococcus infection. Some data suggest that patients with chronic kidney diseases and dialysis are at increased risk for calcific, degenerative mitral stenosis.  The key physical examination findings in hemodynamically significant mitral stenosis may include irregular pulse (due to atrial fibrillation), prominent a wave in the jugular venous examination, tapping apex beat, signs of pulmonary hypertension/right-heart failure, an opening snap, and the classic low-pitched, middiastolic rumbling murmur with presystolic accentuation. A chest radiograph may show the prominence of the pulmonary arteries, the straightening of the left heart border, the LA, and signs of pulmonary edema. The electrocardiogram may show atrial fibrillation or evidence of LA enlargement and right ventricular hypertrophy. The 2-dimensional and Doppler echocardiogram is the best imaging modality for diagnosing mitral stenosis and assessing its severity and hemodynamic consequences.  Medical therapy is used as an initial symptomatic treatment for severe mitral stenosis; however, it does not improve the long-term outcomes of the disease. As assessed by echocardiography, percutaneous mitral balloon commissurotomy (PMBC) is recommended as the first-line treatment for rheumatic mitral stenosis in patients with suitable mitral valve anatomy. Meanwhile, surgical mitral valve repair/replacement is limited to patients whose valves are unsuitable. Valves designed for transcatheter aortic valve replacement have been used in a percutaneous transcatheter mitral valve replacement technique to treat degenerative mitral stenosis. PMBC treats mitral stenosis by splitting the fusion of the mitral valve commissures, and it is most effective in rheumatic mitral stenosis and certain forms of congenital mitral stenosis. This activity will provide a detailed description of the mitral valve, the pathology of mitral stenosis, and possible options for catheter management, including indications, contraindications, complications, and the clinical significance of catheter management.