The most common heart operations are coronary artery bypass surgery and heart valve replacements. When there is a narrowing in the arteries of the heart, there is reduced blood supply, which leads to angina. If the artery gets blocked, it can cause a heart attack. Coronary artery bypass surgery is needed when medicines alone are not sufficient. Stents to coronary artery narrowing’s can be used but in some cases where there is diffuse disease or for technical issues, bypass surgery may be the only option.
The other common heart operation is heart valve surgery. The heart has four valves namely: aortic, mitral, pulmonary and tricuspid valves. These valves can be affected in different medical conditions such as rheumatic disease, infections or function abnormally due to degeneration and sometimes secondary to other problems in the heart. Although rheumatic disease was one of the common causes of valve problems in the past, it is on the decline. Infection of the heart valves is called endocarditis. Medicines can treat this condition but sometimes when the infection is aggressive, surgery will be needed. I.V drug abusers and patients with recurrent dental infections are prone to endocarditis. Sometimes the valves themselves are fine but cannot function properly due to other issues. An example of this is when someone has a heart attack, a part of the heart muscle can die and this part of the heart can dilate (commonly the ventricular chamber of the heart). Because the heart becomes distended, the valve cannot function normally and this causes the valve to leak. Sometimes, the structures supporting the valve, (chordae) which are thin strands break and this can cause valve to leak. Other conditions are due to degenerative disease or small defects in the valve tissue (mitral valve cleft or perforations).If there is a little amount of leak, the heart can tolerate this but if the leak is very big, patients will not tolerate it. Mitral valve is commonly the valve, which has this type of problem.
When the valve is not functioning normally, initially the body tries to cope with it but when this becomes severe, the body cannot tolerate it and in such conditions, they might need an operation. One option is to replace the valve using a metal or a tissue valve. Another option that is becoming more and more popular is valve repair. Here, the valve is repaired so that the patient’s own valve becomes normal and therefore there is no need to replace the valve with an artificial valve. Valve repair surgeries for mitral and tricuspid valves are becoming very common in the western world. Artificial materials like a ring and artificial chordae are sometimes used as a part of the repair.
Does this mean that all valves can be repaired and there is no need for valve replacement surgery? The answer is NO. Although repairing the valve is much better than replacement, it is not possible in every situation and every valve. In rheumatic heart disease, the valve tissues are very thickened and damaged. Besides the valve, the tissues around the valve are also damaged. Therefore in these patients, valve repair is not possible. Some units do valve repair for aortic valve problems particularly in the young patients. But of all the valves, mitral valve is most commonly repaired. This is for conditions I have described above. In addition to valve repair, patients might need coronary artery surgery as well at the same time.
One very important reason why repair is becoming more popular is the availability of intra operative echocardiogram (Transoesophageal echocardiogram or T.O.E). Here a small probe is put in the food pipe during the operation and this allows identifying the specific valve defect and also allows the surgeon to know if the repair is successful in the theatre before completion of surgery. T.O.E has revolutionised valve repair surgery.
The advantages of valve repair are that patient’s own natural tissues are preserved and there is no need for long term use of Warfarin (needed if a mechanical valve is used). Any artificial valve can fail after 10 – 20 years needing a second operation. This will not be the case after a successful repair.
Picture showing a leaking mitral valve due to ruptured chordae. Valve can be preserved by removing the abnormal part of the valve leaflet and repairing it.
Dr. Hemanth Kaukuntla
CARDIOTHORACI SURGEON
FRCS Glas, FRCS Ed, M.D, FRCS C-Th, UK.
Care Hospital, Banjara Hills. Hderabad. India.
Phone 099599979989
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