CARDIAC-CATHETERIZATION AND OTHER IMAGING MODALITIES IN THE EVALUATION OF VALVULAR HEART-DISEASE

This review describes recent publications using cardiac catheterization and diagnostic imaging modalities, excluding transesophageal and transthoracic echocardiography, to evaluate valvular heart disease. Radionuclide techniques and magnetic resonance imaging continue to be studied as to whether they can improve the quantification of valvular regurgitation. As yet, however, they are not justified in the routine evaluation of patients with valvular heart disease. Cardiac catheterization has been used by several authors to assess more completely the obstructive physiology of valve stenosis, including obtaining a better understanding of transvalvular pressure gradients; the phenomenon of downstream pressure recovery; and the utility of valve resistance in quantifying the severity of the valve stenosis, which complements the calculated valve area, especially in cases of low cardiac output. Traditional cardiac catheterization techniques have recently been used to show a sex difference in left ventricular systolic performance in aortic stenosis. Intracardiac ultrasound and electrocardiography are being studied as methods to guide percutaneous valvotomy. The analysis of myocardial tissue samples obtained by endocardial biopsy promises understanding gene-protein-function interactions. Specifically, myosin alterations in aortic valve disease and protooncogene expression in hypertrophy are exciting, emerging areas of investigation.