What is the Mitral Valve?
The mitral valve is a two-leaf structure in the left side of the heart which lies between the atrium (upper chamber) and the ventricle (lower chamber). It opens when the left atrium pumps blood to the ventricle and closes to prevent back flow of the blood as the ventricle pumps the blood forward and away from the heart to the rest of the body.
There are congenital and acquired abnormalities of the mitral valve that cause it to fail from completely opening (mitral valve stenosis) or closing (mitral valve prolapse) every time the heart contracts and relaxes, and these can cause signs and symptoms that lead to eventual heart failure. When medications are not enough to treat these conditions, heart surgery is often indicated to repair or replace the mitral valve.
How is Minimally Invasive Mitral Valve Repair Done?
Unlike traditional open heart surgery where the chest is split open along the breast bone (sternum), minimally invasive mitral valve repair involves creating two to four small (2-inch) incisions on the right chest beside the sternum to reach into the heart. Using a tiny camera and special instruments endoscopic surgery may be done on the diseased valve. A robotically assisted valve surgery may also be done with the aid of a specialized computer that controls the robotic arms and allows three-dimensional viewing of the patient’s heart on an external monitor. If the valve is far too damaged by disease to be repaired, a mitral replacement may be done instead.
This procedure is done under general anesthesia. Instead of attaching the patient to a heart-lung machine like in open surgery to immobilize the heart, medications may be used to slow down the heart during valve repair. It takes about two and half hours on the average to do the surgery with minimal incisions. After the operation the patient’s chest fluids are drained with chest tubes that are generally removed after three days. If the heart rate slows down too much heart failure is prevented by implanting a pacemaker.
What are Advantages and Risks of Minimally Invasive Surgery?
Common complications in mitral valve repair are blood loss, infection, blood clots, stroke, kidney failure and irregular heartbeats. These are minimized in surgery with small incisions. Compared to open chest surgery, minimally invasive approach results in less blood loss, trauma and post-operative pain to the patient. There is also less risk of infection and the patient can recover faster and go home usually within four to five days.
However, not all patients with mitral valve defects are candidates for this procedure. Those who are markedly obese, the elderly and patients who have severely reduced cardiac function are not advised to undergo this approach. Some patients may need a concomitant surgery such as coronary artery bypass grafting and aortic valve repair to be done with the mitral valve repair, so an open procedure might be well indicated.
Minimally invasive surgery involves the use of robotics and computers that require surgical expertise and experience. This is the reason why it is not routinely performed and very few specialists perform the procedure. Its success is influenced by the precision of surgical technique and hospital capabilities in controlling infection and providing good nursing care.
UMMC, “Study Details Safe, Effective, Minimally Invasive Mitral Valve Repair At The University Of Maryland Medical Center” accessed 1/15/11
MedlinePlus, “Mitral valve surgery – minimally invasive” accessed 1/15/11