Partial mitral homograft was used in 22 patients with localized lesions contraindicating a conventional valve repair. The etiologies of valve disease were: calcified rheumatic stenosis (n=14) and acute bacterial endocarditis (n=8). One patient died three months after surgery from cancer. Another patient required reoperation for residual stenosis 14 months postoperatively. All other patients had an excellent functional result with 19 patients in sinus rhythm. In this series, partial homograft replacement of the mitral valve significantly extended the possibilities of reconstructive surgery.

How to cite: Acar, C., Berrebi, A., Tolan, M., & Chachqués, J. C. (1995). Partial mitral homograft: a new technique for mitral valve repair. The Journal of heart valve disease, 4(6), 665–668.

Between 1973 and 1993 sixty aortic homograft valved conduits in fifty-six patients were used to establish continuity between the right ventricle and the pulmonary artery in congenital heart disease. Age range was one day to 23.5 years (median 3.6 years) which included twenty-six patients less than one-year-old. Conduit size ranged from 11 to 23 mm (median 17.6 mm). there were nine hospital deaths and eight late deaths. The 45 survivors have been followed for a median of 8.6 years (range 6 months to 20 years). All patients have had serial echocardiographic assessments and 35 have had post repair cardiac catheterization. Almost all patients had mild-to-moderate degrees of homograft regurgitation. There were eleven with severe homograft regurgitation and two are being considered for reoperation. The follow up homograft gradient ranged from 0 to 64 mmHg (mean 24 mmHg). Freedom from reoperation for conduit obstruction was 98.2% at five years falling to 91% (C.L. 82%-100%) at 10 years. Of the 23 homografts inserted more than 10 years ago, only one (4.3%) has been replaced because it was causing important obstruction. None have been replaced for regurgitation. Our results indicate that larger sized aortic homografts used in reconstruction of the right ventricular outflow tract give satisfactory results and there is a low incidence of reoperation for replacement at medium term follow up.

How to cite: Tam, R. K., Tolan, M. J., Zamvar, V. Y., Slavik, Z., Pickering, R., Keeton, B. R., Salmon, A. P., Webber, S. A., Tsang, V., & Lamb, R. K. (1995). Use of larger sized aortic homograft conduits in right ventricular outflow tract reconstruction. The Journal of heart valve disease, 4(6), 660–664.

Both closing dynamics and the mechanical condition of a Björk-Shiley Convexo-Concave (BSCC) valve are significant in assessing the risks of outlet strut fracture. Risk of fracture increases with the presence of a pre-existing fracture in one of the two strut legs and with magnitude and frequency of loading. Recent analyses of in vivo data collected in clinical studies, and in vitro data from a computer-controlled pulse duplicator, indicate that the condition of an outlet strut can be evaluated by non-invasive passive acoustic measurement. The technique utilizes heuristic methods to identify features in time and frequency in the closing sound of BSCC valves. Because of patient-to-patient and beat-to-beat variability in the waveforms of closing sounds, the sound of beats are cross-correlated to identify thirteen characteristic waveform groups that are independent of valve strut condition. The groups are used for subsequent acceptance of each closing event. For each group, a Mahalanobis distance technique is used to identify features in time and frequency that characterize the mechanical condition of the BSCC valve. A Volterra expansion is used to optimize the features. A similar approach, where strain gages supply the measured strut load, is used to identify features associated with valve closing load, and to predict outlet strut forces on a beat-for-beat basis in vitro and in sheep. The characterization is based on a set of acoustic recordings made on patients prior to explant of each valve. Analysis is made using blinded and leave-one-out methods, preventing overlap between the data used in training and that used in testing. Results have demonstrated a sensitivity and specificity to strut fracture of 100 percent on a group of 33 patients for whom gold standard data was available. Analysis of additional blinded data will be useful to further quantify the robustness of the detection method. The relative ease with which data can be collected, and the excellent results, indicate that the method may develop into a practical and effective screen for outlet strut condition.

How to cite: Eberhardt, A. C., Chassaing, C. E., Ward, M. A., & Lewandowski, S. J. (1995). Acoustic characterization of mechanical valve condition and loading. The Journal of heart valve disease, 4(6), 649–659.

Björk-Shiley Convexo-Concave (CC) valves sometimes experience fracture of the outlet strut. Previously implicated valve characteristics that predict strut fracture include larger valve size, larger opening angle (70 degrees vs 60 degrees), remilling, weld date, and implant in the mitral position. While the associations between risk, size, and opening angle suggest that part of the elevated incidence of strut fracture might be due to the design of the Björk-Shiley valves, only a small fraction of implanted valves have experienced strut fracture. In consequence, previously unexamined variations in the manufacturing process have been suggested as possible factors affecting the failure risk of individual valves; materials, manufacturing steps, quality control, and specific workers have all been put forward as potential explanations for valve-to-valve variation in risk. We conducted a case-control study of CC60 degrees valves implanted in the USA and Canada and manufactured between January 1, 1979 and March 31, 1984. Cases included all verified strut fractures reported to the manufacturer from 1979 through January, 1992. up to 10 controls were selected for each case. Controls were matched to cases on implanting surgeon and were required to have been implanted and functioning at least as long as their respective case valves. We reviewed case and control manufacturing records. There were 150 cases and 1095 surgeon-matched controls. Large mitral valves were at greatest risk of strut fracture; 33mm mitral valves were estimated to be 23 times more likely to fracture than 21-25mm aortic valves. Valves welded in 1979 and 1980 were less likely to fracture than those welded in any other time period; however, no specific manufacturing procedures or personnel were uniquely associated with this time period. Valves with more flexible outlet struts, as determined by the hook deflection and load deflection tests during manufacture, appear to have been at higher risk than valves with more rigid outlet struts. There were three welders who had worked on a sufficient number of valves to allow separate estimation of the risk in the valves they welded. One welder's work was associated with about one-third the risk of valves worked on by the other two. Examination of receiver operating characteristic curves revealed, however, that welder identity added little to the discriminating information already available in the form of valve size and implant position. It is concluded that welder identity and strut flexibility appear to contribute to the risk of outlet strut fracture in Björk-Shiley CC60 degrees valves. Neither of these factors, however, is sufficient to account for much of the previously unexplained variation in risk. No other characteristic measurable in existing manufacturing records appears to predict risk of strut fracture in any useful way.

How to cite: Walker, A. M., Funch, D. P., Sulsky, S. I., & Dreyer, N. A. (1995). Manufacturing characteristics associated with strut fracture in Björk-Shiley 60 degrees Convexo-Concave heart valves. The Journal of heart valve disease, 4(6), 640–648.

In a prospective study, 292 consecutive patients received 336 Omnicarbon cardiac valves from September 1984 through September 1992 at the Montpellier University Hospital. There were 153 aortic (52%), 95 mitral (33%) and 44 double (15%) mitral and aortic replacements. Mean age was 58 years; 57% were male. Total follow up was 1,383 patient-years, with a maximum of nine and a mean of 4.87 years. Early mortality was 2.75% overall. Late mortality occurred at a rate of 1.9%/patient-year. Nine-year probability of freedom from mortality (including early mortality) was 85.0% +/- 2.6% overall. There were no cases of structural failure. Thromboembolic events occurred in nine patients, producing a linearized rate of 0.7%/patient-year. Hemorrhage associated with anticoagulant therapy occurred at a rate of 0.8%/patient-year. Therefore, the combined rate of thromboembolic/hemorrhagic events was 1.5%/patient-year. Cumulative overall freedom from thromboembolism and hemorrhage was 91.5% +/- 1.9% at nine years; it was 86.2% +/- 4.3% after mitral and 95.1% +/- 2.0% after aortic valve replacement. Hemolytic anemia was not observed. Endocarditis occurred eight times (0.6%/patient-year), and there were seven cases of perivalvular lead (0.5%/patient-year). At the end of the follow up, 86% of the patients were in NYHA class I. It is concluded that clinical results over a nine-year period are excellent with the Omnicarbon prosthesis.

How to cite: Thevenet, A., & Albat, B. (1995). Long term follow up of 292 patients after valve replacement with the Omnicarbon prosthetic valve. The Journal of heart valve disease, 4(6), 634–639.

Seven and a half year clinical experience with the CarboMedics prosthetic heart valve is presented. A total of 287 valves were inserted in 277 patients. The first 132 patients were followed in a prospective, and the remaining 145 patients in a partly prospective and partly retrospective manner. The follow up was 98.9% complete with a total of 1,055 patient-years. Actuarial survival at 7.5 years was 74.0% +/- 3.5% overall; 76.0% +/- 4.3% for single aortic, 75.0% +/- 6.5% for single mitral and 76.0% +/- 11.4% for double valve replacements. The actuarial rates of freedom from complications were as follows: valve thrombosis 99.6% +/- 0.4%, embolism 96.0% +/- 1.7%, and anticoagulant-related bleeding 88.0% +/- 2.4%. There was no hemolysis, prosthetic valve dysfunction, or structural deterioration. The linearized rates per 100 patients-years were as follows: valve thrombosis 0.09 (mitral 0.30); embolism 0.75 (aortic 0.31, mitral 1.80); anticoagulant related bleeding 2.84; paravalvular leakage overall 0.19 (aortic 0.31); prosthetic valve endocarditis 0.19 (aortic 0.31). Over a 7.5-year time frame, the CarboMedics prosthetic heart valve has been highly reliable with a low incidence of valve related complications.

How to cite: Aagaard, J., Hansen, C. N., Tingleff, J., & Rygg, I. (1995). Seven-and-a-half years clinical experience with the CarboMedics prosthetic heart valve. The Journal of heart valve disease, 4(6), 628–633.

Mitral annulus anatomy and dynamics were evaluated in 12 subjects using a three-dimensional transesophageal echocardiographic technique. The mitral annular area, diameters and distance from the left ventricular apex were measured in end-diastole, mid-systole, end-systole and mid-diastole. The mitral annulus had its largest area in end-systole and the smallest area in end-diastole. The shape of the annulus changed during the cardiac cycle with the maximal change occurring in the diameters passing close to the middle of the mitral leaflets. In the vertical plane, the annulus had a shallow ski-slope shape, with the attachment of the anterior leaflet being farthest from the apex. In other words, the highest point of the annulus was situated anteromedially and was visualized in the long axis imaging plane.

How to cite: Pai, R. G., Tanimoto, M., Jintapakorn, W., Azevedo, J., Pandian, N. G., & Shah, P. M. (1995). Volume-rendered three-dimensional dynamic anatomy of the mitral annulus using a transesophageal echocardiographic technique. The Journal of heart valve disease, 4(6), 623–627.

The bicuspid aortic valve is the most frequent congenital cardiac malformation; it may be isolated or associated with other congenital heart disease. The present investigation consists of a study of bicuspid aortic valves in 1022 heart specimens belonging to the anatomical collection of the Institute of Pathological Anatomy of the University of Padua. A bicuspid aortic valve was observed in 95 specimens. It occurred as an isolated congenital cardiac defect in 28 cases, seven of which had spontaneous laceration of the aortic valve (aortic dissection). It was associated with other congenital cardiac malformations in 67 out of the remaining 994 specimens (6.7%), 41 of which (61.2%) showed obstruction of the aortic arch. The frequency of bicuspid aortic valve in specimens with complete transposition of great arteries was only 1%. Bicuspid aortic valve was particularly frequent in association with ventricular septal defect and was significantly more frequent in cases with (51.1%) than in cases without (20.5%) aortic arch obstruction (p < 0.001). There was no significant relationship between the occurrence of bicuspid aortic valves and left ventricular outflow tract obstructions or mitral valve malformations. The morphology of the pulmonary valve was also examined. Concurrence of a bicuspid aortic and pulmonary valve was detected in 11 specimens, five of these had trisomy-18. Our findings cast doubt on the assumption that altered fetal blood flow through the aortic valve may be the main factor producing the bicuspid condition. Indeed, they rather support the hypothesis that most bicuspid aortic valves are expressions of a developmental complex that affects the aortic arch and the wall of the ascending aorta as well as the aorta valve.

How to cite: Duran, A. C., Frescura, C., Sans-Coma, V., Angelini, A., Basso, C., & Thiene, G. (1995). Bicuspid aortic valves in hearts with other congenital heart disease. The Journal of heart valve disease, 4(6), 581–590.