An updated set of guidelines jointly released by the American College of Cardiology ( ACC ) and the American Heart Association ( AHA ) draws together the latest information on the diagnosis and treatment of patients with valvular heart disease.

Valve disease most often strikes the mitral valve, which controls blood flow between the left atrium and the left ventricle, or the aortic valve ( most prevalent type ), which controls blood flow between the left ventricle and the aorta. Valvular heart disease caused about 20,000 deaths in 2003. The total mentioned mortality ( i.e., underlying or contributing number of deaths ) is about 42,500. There were 95,000 first-listed hospital discharges in 2003 for valvular heart disease. An estimated 95,000 inpatient valve procedures were performed in the United States in 2003.

The guidelines discuss evaluating patients with heart murmurs, preventing and treating endocarditis, managing valve disease in pregnancy, and treating patients with concomitant coronary artery disease, as well as more specialized issues regarding specific valve lesions.

The new guidelines update an earlier set released in 1998. One of the key changes in the 2006 document is a focus on the proper timing of valve surgery. The guidelines include more precise and quantitative definitions of mild, moderate and severe valvular disease, based on the patient's symptoms and the results of exercise testing, echocardiography, and other tests. This change may prompt earlier referral of some patients for surgery, even before they develop noticeable symptoms.

" The guidelines encourage physicians to look behind the scenes, rather than waiting for symptoms to develop," said Patrick T. O'Gara, at Brigham & Women's Hospital and Harvard Medical School, Boston. " For example, an abnormal response to exercise could help identify patients with aortic stenosis who may be candidates for surgery sooner rather than later."

Other highlights of the guidelines include:

Surgical advances that increasingly permit repair, rather than replacement, of heart valves in many patients. These are particularly important for some patients with leaky mitral valves and are increasingly used in selected patients with aortic valve regurgitation.

The use of echocardiography in the operating room to guide surgery. This procedure, known as transesophageal echocardiography, involves passing a probe into the esophagus and using sound waves to create real-time pictures of the heart.

Further clarification of the use of blood thinners in patients who have undergone heart valve surgery.

An update on preventive medical treatment for some heart valve conditions.

The guidelines also acknowledge the complexity of managing many patients with valvular heart disease, including the selection of replacement heart valves. For example, a young woman who has surgery to replace a diseased heart valve with a mechanical heart valve would need blood-thinning medications to prevent blood clotting and stroke. If she became pregnant, blood thinners would pose a toxic risk to the fetus. Implanting a biological heart valve would eliminate the need for blood thinners, but it would be unlikely to last a lifetime, necessitating another open-chest surgery in the future.

Source: American College of Cardiology, 2006


XagenaMedicine2006



Link: Xapedia - Medical Encyclopedia