Abstract
Severe secondary mitral regurgitation carries a poor prognosis with one in five patients dying within 12 months of diagnosis. Fortunately, there are now a number of safe and effective therapies available to improve outcomes. Here, we summarise the most up-to-date treatments. Optimal guideline-directed medical therapy is the mainstay therapy and has been shown to reduce the severity of mitral regurgitation in 40-45% of patients. Rapid medication titration protocols reduce heart failure hospitalisation and facilitate earlier referral for device therapy. The pursuit of sinus rhythm in patients with atrial fibrillation has been shown to significantly reduce mitral regurgitation severity, as has the use of cardiac resynchronisation devices in patients who meet guideline-directed criteria. Finally, we highlight the key role of mitral valve intervention, particularly transcatheter edge-to-edge repair (TEER) for management of moderate-severe mitral regurgitation in carefully selected patients with poor left ventricular systolic function, with a number needed to treat of 3.1 to reduce heart failure hospitalisation and 5.9 to reduce all-cause death. To slow the rapid accumulation of morbidity and mortality, we advocate a proactive approach with accelerated medical optimisation, followed by management of atrial fibrillation and cardiac resynchronisation therapy if indicated, then, rapid referral to the Heart Team for consideration of mitral valve intervention in patients with ongoing symptoms and at least moderate-severe mitral regurgitation. Mitral TEER has been shown to be 'reasonably cost-effective' (but not cost-saving) in the UK in selected patients, although TEER remains underused with only 6.5 procedures per million population (pmp) compared with Germany (77 pmp), Switzerland (44 pmp) and the USA (32 pmp).