Mixed valvular heart disease: diagnosis and management

Mixed valvular diseases (MVDs) are common but have received little attention in the literature, especially regarding the mitral valve (MV) and the right-sided cardiac valves. Whereas echocardiography plays a pivotal diagnostic role, the diagnosis is made difficult due to haemodynamic interactions that may invalidate common indices of severity used in isolated stenosis or regurgitation. The diagnostic strategy should aim at initially separately assessing stenosis and regurgitation, taking into account the diagnostic pitfalls, with complementary use of multimodality imaging in cases of persisting diagnostic uncertainties. Unlike aortic stenosis, the calcium score cannot be used as a surrogate for haemodynamic severity of mixed MV disease. Severe stenosis and/or severe regurgitation are indicative of severe MVD, and management should follow recommendations on the predominant lesion. However, some patients with the combination of moderate stenosis and moderate regurgitation have a poor prognosis when left untreated. Concordant data suggest that, in patients with mixed aortic or MV disease, transvalvular velocities and pressure gradients are more powerful prognostic indicators than valve area or the severity of regurgitation. It is essential to consider the global repercussions that indicate poor outcomes in patients with MVD. However, whereas symptoms and/or ventricular dysfunction are considered as clear indication for intervention, imaging cut-offs have not been validated for balanced moderate regurgitation and stenosis. Although emerging evidence tends to support earlier management, further prospective studies are required, and pending the results of these studies, asymptomatic patients with MVD should be closely monitored.