MITRAL VALVE REPAIR DIAGNOSIS RESULTS

mitral valve repair - Diagnosis Preparation
Mitral valve stenosis is diagnosed by history, physical examination, listening to the sounds of the heart (cardiac auscultation), chest x ray, and ECG. Patients may have no symptoms of a valve disorder or may have shortness of breath (dyspnea), fatigue, or pulmonary edema (fluid in the lungs). Other patients present with atrial fibrillation (a cardiac arrhythmia) or an embolic event (result of a blood clot). Doppler echocardiography is the preferred diagnostic tool for evaluation of mitral valve stenosis, and can be performed in conjunction with non-invasive exercise testing by treadmill or bicycle.

Cardiac catheterization is reserved for patients who demonstrate discrepancies in Doppler testing. Both left- and right-heart catheterization should be performed in the presence of elevated pulmonary artery pressures. A diagnosis of mitral insufficiency requires a detailed patient history. Listening to the heart (auscultation) reveals the presence of a third heart sound. Chest x ray and ECG provide additional information. Again, Doppler echocardiography provides valuable information. Exercise testing with Doppler echocardiography can show the true severity of the disease.

After initial findings, patients may be followed with repeat visits and testing to monitor disease progress. If the patient has reached NYHA Class III or IV, replacement is considered. Severe pulmonary hypertension with pulmonary artery systolic pressures greater than 60 mm Hg is considered an indication for surgery. Left ventricular ejection fraction less than 60% also is an indication for surgery.

Aftercare
The patient receives continued cardiac monitoring in the intensive care unit and usually remains in intensive care for 24–48 hours after surgery. Ventilation support is discontinued when the patient is able to breathe on his/her own. If mechanical circulatory support and inotropic agents (a substance that influences the force of muscle contractions, e.g. digitalis) were needed during the surgical procedure, they are discontinued as cardiac function recovers. Tubes draining blood from the chest cavity are removed as bleeding from the surgical procedure decreases. Prophylactic antibiotics are given to prevent infective endocarditis and prevent the recurrence of rheumatic carditis.

If the patient recovers normally, discharge from the hospital occurs within a week of surgery. At discharge, the patient is given specific instructions about wound care and infection recognition, as well as contact information for the physician and guidelines about when a visit to the emergency room is indicated. Within three to four weeks after discharge, the patient is seen for followup office visit with the physician, at which time physical status will have improved for evaluation. Thereafter, asymptomatic, uncomplicated patients are seen at yearly intervals. Few limitations are placed on patient activity once recovery is complete.

Risks
There are always risks associated with general anesthesia and cardiopulmonary bypass. Risks specifically associated with mitral valve repair include embolism, bleeding, or operative valvular endocarditis. When valve repair does not produce adequate results, then increased operative time is required to replace the mitral valve. If the patient’s mitral valve is replaced with a mechanical valve, the patient must take an anticoagulation drug, such as Coumadin, for the rest of his/her life. An inadequately repaired valve, if left untreated, results in continued myocardial dysfunction resulting in pulmonary edema, congestive heart failure, and systemic thromboemboli generation.

Normal results
Patients treated by mitral valve repair for mitral insufficiency can expect improved myocardial function and relief of symptoms. Oxygen consumption by skeletal muscle continues to improve. Cardiac output improves and pulmonary hypertension resolves over several months after the initial decrease in left atrial pressure, pulmonary artery pressure, and pulmonary arteriolar resistance.

Excellent results in terms of improved cardiac function and symptom relief also are expected for patients that undergo mitral valve repair for mitral stenosis.

Morbidity and mortality rates Operative mortality associated with mitral valve repair for stenosis is 1–3%. The prognosis for restenosis (re-narrowing) is 30% at five years and 60% at nine years; additional surgery is required in 4–7% of patients at five years. Eighty to 90% of patients whose mitral valve stenosis was repaired by commissurotomy are complication free at five years after surgery.

Mitral valve repair for mitral insufficiency is the preferred approach because it preserves the valvular apparatus and left ventricular function. It also eliminates the risk of mechanical valve failure and the need for lifelong anticoagulation.

Alternatives
The asymptomatic patient with a history of rheumatic fever can be treated with prophylactic antibiotics and followed until symptoms are appear. If atrial fibrillation develops antiarrhythmic medications can be used for treatment. Atrial defibrillation may relieve atrial fibrillation. Anticoagulants may be prescribed to prevent the occurrence of systemic embolization.

Mitral valve repair for mitral regurgitation is not as successful if the anterior leaflet is involved. Rheumatic, ischemic, or calcific diseases decrease the likelihood of repair in even the most skilled hands. In the absence of mitral valve replacement, mitral valve repair is indicated.