SURGICAL REPAIR AND RECONSTRUCTION OF VALVULAR LESIONS

Thirty-six years have passed since the inception of mitral valve repai r by Lillehei and McGoon. In the period presently under review it is a pparent that mitral valve repair and the late results have become more predictable. Previously, repair was not attempted because of concern that valve replacement, with its attendant problems, might be necessar y. This attitude appears to be slowly changing. The current issue is w hether patients who have severe mitral regurgitation but are relativel y asymptomatic should be referred for repair before ventricular functi on deteriorates or atrial fibrillation develops. Current evidence sugg ests that approximately 10% of asymptomatic patients will progress suf ficiently each year to require surgical intervention. Systolic anterio r motion of the mitral valve causing left ventricular outflow tract ob struction, has, since the era of routine intraoperative transesophagea l echocardiography, become a well-recognized occasional consequence of mitral valve repair. Numerous theories have been suggested as to its cause: the most plausible suggest that risk factors include the presen ce of excess valvular tissue, a bulging septum, a nondilated hyperdyna mic left ventricle, and a narrow mitral-aortic angle. The fact that nu merous annuloplasty techniques exist, each having its own proponent(s) , suggests that different techniques or types of annuloplasty are equa lly effective. Reparative techniques for the aortic valve have lagged behind those for the mitral valve because of limited previous success. The type of valve pathology was recently classified in terms of repai r and new techniques, which are briefly documented, have been tried. I n industrialized societies, where rheumatic fever is uncommon, annuloa ortic ectasia is the most common reason for aortic valve regurgitation and replacement. In many patients the valve cusps, which are often no rmal, can be preserved using innovative techniques. Surgical repair of the tricuspid valve is infrequently undertaken and, because this valv e is exposed to low pressure, is often successful. The issues involved with repair are reviewed, as are suggestions as to which annuloplasty to use. The use of a resorbable De Vega annuloplasty in patients with low pulmonary vascular resistance who are undergoing concomitant left -sided valve surgery is particularly innovative.