thus restoring the natural anatomy of the valve. With both techniques, an annuloplasty ring is typically secured to the annulus, or opening of the mitral valve, to provide additional structural support. In some cases, the "double orifice" (or 'Alfieri') technique for mitral valve repair, the opening of the mitral valve is sewn closed in the middle, leaving the two ends still able to open. This ensures that the mitral valve closes when the left ventricle pumps blood, yet allows the mitral valve to open at the two ends to fill the left ventricle with blood before it pumps. In general, mitral valve surgery requires "open-heart" surgery in which the heart is arrested and the patient is placed on a heart-lung machine (cardiopulmonary bypass). This allows the complex surgery to proceed in a still environment. Due to the physiological stress associated with open-heart surgery, elderly and very sick patients may be subject to increased risk, and may not be candidates for this type of surgery. As a consequence, there are attempts to identify means of correcting MR on a beating heart. The Alfieri technique for instance, has been replicated using a percutaneous catheter technique, which installs a "MitraClip" device to hold the middle of the mitral valve closed. Indications for surgery for chronic MR include signs of left ventricular dysfunction with ejection fraction less than 60%, severe pulmonary hypertension with pulmonary artery systolic pressure greater than 50 mmHg at rest or 60 mmHg during activity, and new-onset atrial fibrillation. Epidemiology Significant mitral valve regurgitation has a prevalence of approximately 2% of the population, affecting males and females equally. It is one of the two most common valvular heart diseases in the elderly, and the commonest type of valvular heart disease in low and middle income countries. In a study of 595 male elite football players aged 18–38 and 47 sedentary non-athletes, mitral regurgitation was found in 20% football players and 15% in control group. Football players with mitral regurgitation were found to have larger mitral annulus diameter compared to athletes without regurgitation, and left atrium diameter was larger in athletes with MR. See also Tricuspid regurgitation Aortic regurgitation Pulmonary insufficiency References External links Valvular heart disease Chronic rheumatic heart diseases