Quantification of mitral regurgitation by echocardiography

### Learning objectives Mitral regurgitation (MR) is becoming increasingly prevalent, despite the reduced incidence of rheumatic disease, and is anticipated to increase in prevalence as the population ages. Approximately 10% of people ≥75 years of age have significant MR; these patients have decreased survival regardless of whether MR is a consequence of a primary mitral valve abnormality or secondary to left ventricular (LV) dysfunction.1 Surgery is only indicated in patients with severe MR, so an accurate quantification of MR severity is mandatory. Several methods may be used for quantification of MR severity. Cardiac magnetic resonance (CMR) can be used for MR evaluation and provides assessment of the effects of regurgitant lesions on cardiac chambers; however, it is not widely available, dedicated imaging phases are required that can be time consuming, significant experience is necessary, and accuracy and reproducibility data are limited. Using cardiac catheterisation, assessment of regurgitation may be limited when based on a single projection and requires assumptions regarding jet geometry. Cardiac CT (CCT) has the highest spatial resolution, but limitations arise from its poor temporal resolution, its inability to assess flow, and radiation exposure.2 Echocardiography remains the cornerstone for the evaluation of MR. It allows comprehensive evaluation of MR, from aetiology and mechanism to severity assessment and impact on cardiac morphology and function. Transthoracic echocardiography (TTE) is the first line imaging technique for the diagnosis and complete evaluation of MR. In most cases TTE is enough to derive a full characterisation of the pathology. However, in selected cases of poor acoustic …