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Any heart valve can become stenotic or insufficient, causing hemodynamic changes long before symptoms. Most often, valvular stenosis or insufficiency occurs in isolation in individual valves, but multiple valvular disorders may coexist and a single valve may be both stenosed and insufficient.
Diagnosis involves echocardiography. Standard 2-dimensional studies show the anatomy. Doppler echocardiography evaluates pressure gradients and blood flow.
Management of a valvular lesion commonly requires only periodic observation, with no active treatment for many years. Intervention is usually indicated only when a moderate or severe valvular lesion causes symptoms or cardiac dysfunction. The intervention may involve valvuloplasty or valve replacement and may be carried out either percutaneously or surgically. If coronary artery bypass surgery is being done, it is usual to surgically treat (during the same operation) any moderate or severe valve lesions, even if asymptomatic.
Two kinds of valve prosthesis are used:
Traditionally, a mechanical valve has been used in patients < 65 and in older patients with a long life expectancy because bioprosthetic valves deteriorate over 10 to 12 yr. Patients with a mechanical valve or bioprosthetic mitral valve require lifelong anticoagulation (to prevent thromboembolism) and antibiotics before some medical or dental procedures (to prevent endocarditis). An aortic bioprosthetic valve, which does not require anticoagulation beyond the immediate postoperative period, has been used in patients > 65, younger patients with a life expectancy < 10 yr, and those with some right-sided lesions. However, newer bioprosthetic valves may be more durable than 1st-generation valves; thus, patient preference regarding valve type can now be considered.
Women of childbearing age who require valve replacement and plan to become pregnant must balance the teratogenic risk due to warfarin when mechanical valves are used against the risk of accelerated valve deterioration when bioprosthetic valves are used. Teratogenic risks can be reduced by use of heparin instead of warfarin in the first 12 wk and last 2 wk of the pregnancy, but management is difficult and careful discussion is required before surgery.
Endocarditis prophylaxis is rarely indicated for patients with native valve disorders.
Last full review/revision November 2012 by Guy P. Armstrong
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