Echophonocardiographic evaluation of normal and abnormal prosthetic valve function.
In addition to the clinical examination, echophonocardiography is mandatory in the diagnostic evaluation of patients with suspected prosthetic valve malfunction. Two-dimensional echocardiography is particularly useful in assessing patients with porcine valve heterografts. Valve alignment, ring motion, and individual leaflet motion can be better evaluated with this technique than by M-mode echocardiography. In addition, porcine prosthetic valve malfunction can be readily differentiated from severe left ventricular dysfunction by two-dimensional echocardiography. With regard to the metallic valves, two-dimensional echocardiography (especially with phased array systems) offers little or no advantage over M-mode echocardiography. Moreover, side lobe echoes from the suture ring and reverberating echoes from the metallic disc or leaflet may mask underlying prosthetic valve malfunction or be misinterpreted as representing intra-atrial masses. Combined echophonocardiography permits measurement of time intervals; changes in these intervals may be useful in predicting prosthetic valve malfunction, particularly if the patient serves as his own control. The characteristic M-mode echocardiographic and phonocardiographic findings in the commonly used prosthetic valves are highlighted in this review. The clinician must be aware of the range of normal and abnormal findings for each particular prosthetic valve.
D001021:Aortic Valve; D001283:Atrioventricular Node / Q000503:physiopathology; D001705:Bioprosthesis; D002933:Cineradiography; D004452:Echocardiography / Q000379:methods*; D006350:Heart Valve Prosthesis / Q000009:adverse effects; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008943:Mitral Valve; D010701:Phonocardiography / Q000379:methods*