Functional Mitral Regurgitation

Mitral valve regurgitation is one of the most common valve lesions. Clinical decision making for mitral regurgitation depends on accurate assessment of the mechanism and quantitation of mitral regurgitation. The mechanism of mitral regurgitation in a significant proportion of patients especially in the developed countries is functional. The mechanism underlying functional mitral regurgitation is due to left ventricular dilation. Furthermore, as functional mitral regurgitation is by nature a dynamic problem, accurate assessment of severity can be challenging. Echocardiography which enables real time imaging of the heart is the primary imaging modality in the diagnosis and assessment of functional mitral regurgitation. Important information can be obtained from a systematic echocardiographic assessment of the whole mitral apparatus and the underlying ventricular myocardium. Due to the complex spatial and dynamic pattern of flow across the mitral valve in patients with functional mitral regurgitation, obtaining accurate flow quantification using standard two-dimensional measures can be challenging. Three-dimensional echocardiographic techniques have been successful in overcoming some of the inherent geometric limitations of two-dimensional imaging. This chapter outlines the key aspects of functional mitral regurgitation and includes an overview of the anatomy of the mitral valve in the context of functional mitral regurgitation and standard flow measures as assessed using two-and three dimensional echocardiography.