AR, and in 22 of 25 patients (88%) with l+ AR. Saal et al3showed that pulsed Doppler echocardiographyidenti- fied the presence of AR in 34 of 35 patients (97%) with documentedAR. AR was diagnosedby pulsed Doppler echocardiography in 29%of our elderly patients. The AR was severe or moderate in 70 of our 122 patients (57%) with AR. Grayburn et al1 heard an AR murmur in 60 of 82 patients (73%) with AR documented by supravalvular aortography and in 2 of 24 patients (8%) with a normal aortogram.Saal et al3 heard an AR murmur in 28 of 35 patients (80%) with angiographically documented AR and in 1 of 10 patients (10%) without AR. Meyers et al4 heardan AR murmur in 48 of 66 patients (73%) with AR documented by supravalvular aortography and in 2 of 9 patients (22%) without AR. An AR murmur was heard in 105of our 131 patients (80%) with AR demonstrated by pulsed Doppler echocardiography, in 70 of our 74 patients (95%) with severe or moderate AR, in 35 of our 57 patients (61%) with mild AR and in 8 of our 312 patients (3%) without AR. TABLE I Aortic Regurgitation (AR) Murmur Correlated with Presence or Absence of AR Diagnosed by Pulsed Doppler 1. Grayburn PA, Smith MD, Handshoe R, Friedman BJ, DeMaria AN. Detec- tion of aortic insufficiency by standard echocardiography, pulsed Doppler echo- cardiography, and auscultation. A comparison of accuracies. Ann Intern Med 1986;104:599-605. 2. Ciobanu M, Abassi AS, Allen M, Hermer A, Spellberg R. Pulsed Doppler echocardiography in the diagnosis and estimation of severity of aortic insufficien- cy. Am J Cardiol 1982;49:339-343. 3. Saal AK, Gross BW, Franklin DW, Pearlman AS. Noninvasive detection of aortic insufficiency in patients with mitral stenosis by pulsed Doppler echocardi- ography. JACC 1985;5:176-181. 4. Meyers DG, Sagar KB, Ingram RF, Paulsen WJH, Romhilt DW. Diagnosis of aortic insufficiency: comparison of auscultation and M-mode echocardiography to angiography. Southern Med J 1982;75:1192-1194. Mode of Failure of the Hancock Pericardial Valve Xenograft Gaetano Thiene, MD, Uberto Bortolotti, MD, Marialuisa Valente, MD, Aldo Milano, MD, Fiorella Calabrese, MD, Enrico Talenti, MD, Alessandro Mazzucco, MD, and Vincenzo Gallucci, MD B ioprostheses made of bovine pericardium became they had superior hemodynamic performancecompared popular as cardiac valve substitutes mainly because with porcine bioprostheses.1%2 However, after a period of initial enthusiasm, reports showed that some of these From the Departments of Pathology, Cardiovascular Surgery and Ra- devices are not free of complications.3-7 We8 have ob- diology, University of Padua, Medical School, 35 121 Padua, Italy. This study was supported by the Ministry of Education and grant served similar results at medium-term follow-up in pa- 87.00719.57 from the National Research Council, Target Project “Bio- tients with the Hancock pericardial xenograft. We now medical Technology”, Rome, Italy. Manuscript received June 20, 1988; describe the pathologic substratesof failure of such de- revised manuscript received and accepted September 13, 1988. vices. FIGURE 1. A, view of an unimplanted Hancock pericardial valve xenografl, showing the cross stitches suturing the leaflet to the stent post. The arrow indimtes the vertical top stitch that aligns the confluent cusps at each commissure. B, typical tear at 1 commissure, in correspondence with the vertical top stitch (arrow) in an aortic xenograft explanted 39 months after operation because of valve regurgitation. THE AMERICAN JOURNAL OF CARDIOLOGY JANUARY 1. 1989 12