Search

Background: Stentless bioprostheses are anticipated to cause improved hemodynamics and increased longevity over stented bioprosthesis. We have compared echocardiographic analysis of stented bioprosthesis "Freestyle" with stented "Mosaic" bioprosthesis. Because of similar technology (0 pressure fixation, anticalcification) any differences may relate to stent., Methods: Twenty-eight patients undergoing AVR were randomly assigned to receive either stented or stentless. Echocardiograms, by means of M-mode and Doppler were performed early, 3-6 months and 1 year postoperatively., Results: The peak flow velocity was significantly lower in the stentless group, especially 1 week and 6 months after surgery. Mean transvalvular gradient dropped significantly in stentless group and did not change in stented group. EOA did not change significantly in either of groups. AoV velocity time integral was increasing in stentless group. LV mass had fallen significantly in both groups but degree of mass reduction was comparable., Conclusions: There are marked improvements of stentless valves hemodynamics. However it is not necessary equal to higher degree of LV mass reduction during 1 year follow-up.

Background: We report the mid-term results of a prospective trial of a new bioprosthetic valve. The Mosaic bioprosthesis consists of porcine aortic valve that has been cross linked ed in glutaraldehyde solution under zero-pressure fixation and treated with alpha amino oleic acid to reduce the potential for calcification., Methods: Mosaic bioprosthetic valve replacement was performed in 67 consecutive patients between January 1995 and August 1998. There were 37 patients having aortic valve replacement (AVR) and 30 having mitral valve replacement (MVR) who entered this study. The patients age ranged 56 to 86 years (mean 74.9); 38 were female and 29 were male; 44 were in NYHA grade 3 and 21 were NYHA grade 4. All mitral valve replacements were performed with total preservation of subvalvular apparatus. Echocardiographic assessment of valve and LV function were performed on 7th day, 6 months 1,2 and 3 years., Results: There was no hospital mortality. 3 year survival was 85.9+/-5.9% for AVR and 100% for MVR. Freedom from antithromboembolic related haemorrhage has been 96.7% for MVR and 91.9% for AVR. Freedom from the transient neurological event was 96.7+/-3.3% for MVR and 100% for AVR Freedom from structural valve failure, permanent thromboembolism, thrombosis or endocarditis has been 100% for both AVR and MVR. In AVR group left ventricle mass, left ventricle mass index significantly decreased, when cardiac index and effective orifice area increased significantly during study period. Transvalvular gradient did not change. In MVR group transvalvular gradient, effective orifice area and cardiac index did not change., Conclusions: The valve was user friendly. The early results are very satisfactory. Echocardiography measurements after aortic valve replacement are showing very marked late postoperative remodelling of left ventricle. After mitral valve replacement there were exceptionally low transvalvular gradients, no left ventricle outflow tract obstruction.

Background: To evaluate the homeostasis of myocardium during simultaneous continuous retrograde and antegrade cardioplegia vs retrograde continuous cardioplegia., Methods: 40 patients who underwent elective operation of coronary arteries bypass grafting were randomly assigned to 2 groups: group one consisted of 24 patients who received retrograde continuous blood cardioplegia; group two consisted of 16 patients who received simultaneous continuous ante/retrograde cardioplegia. The following measurements were taken: acidosis, oxygen content, oxygen extraction and oxygen consumption; they were taken before and after cross-clamp releasing from coronary sinus effluent and from arterial line. Incidence of low cardiac output, ventricular fibrillation, raised cardiac enzymes and ischemic changes on ECG was noted., Results: In simultaneous group such parameters as acidosis, oxygen content, oxygen extraction and myocardial oxygen consumption recovered after cross-clamping and changes of their values were respectively: 0.0005, 0.87 ml/100 ml, 0.098 and 1.4 ml/min. The same parameters didn't recovered in retrograde group and changes were respectively: 0.05 - p=0.2; 3.7 ml/100 ml - p=0.006, 0.29 p=0.006 and 7.4 ml/min - p=0.03. These changes were significant between groups., Conclusions: Metabolic viability of myocardium measured with oxygen utilisation is better preserved with simultaneous antegrade and retrograde cardioplegia.

Unlabelled: To evaluate the results of mechanical prosthetic valve replacement for active endocarditis 71 patients were reviewed. They were treated surgically between 1988 and 1993 in our institution. Mechanical valves were used in 54 patients (group 1) and bioprosthetic valves were used in 17 patients (group 2). In terms of demographic, clinical and surgical variables prior to operation groups were statistically the same. Follow up ranged from 2-63 months averaged 21 months. This study was carried out to: asses cardiac status postoperatively and assess the rate of mortality, recurrency and reoperations., Methods: Evaluation of cardiac status was assessed on the basis of symptoms and findings by examination, ECG, X-ray, echocardiography, and laboratory tests. Data analysis was done by means of statistical tests like: Student's "t"-test, Fisher exact test, one sided test of difference between two percentages, Kaplan Meyer survival analysis and Cox test., Results: 4-year mortality was 20% in group 1 comparing to 28,6% in group 2, when early mortality were 13% in group 1 comparing to 17% in group 2. These differences were not significant. The recurrency rate was 8,5% in group 1 comparing to 28,6% in group 2 which was statistically significant (p=0.028). Especially early recurrency rates differed significantly between groups and were 4,2% in group 1 comparing to 21% in group 2 (p=0.022). The reoperations rate was 4,2% in group 1 comparing to 21% in group 2 which was statistically significant (p=0.022). Clinical status showed satisfactory values and significant improvement in both groups, slightly better after mechanical valve replacement., Conclusion: It is concluded that mechanical valve is recommended for valve replacement in active valvular endocarditis first of all due to low recurrency and reoperation rate.