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Background and Aim of the Study: The study aim was to compare the hydrodynamics of the Carpentier-Edwards Magna 21 (CEM) and St. Jude Medical Biocor-Epic-Supra 21 (SJME) valves at increasing stroke volume and pulse rate in two different aortic conduits, namely straight and with sinuses of Valsalva present., Methods: Both valve types were tested in the aortic chamber of the Sheffield pulse duplicator, at rates of 70, 80 and 90 beats/min, and stroke volumes of 50 and 60 ml. The systolic and diastolic performances were each recorded. The leaflet coaptation time, ventricle isovolumetric time and maximum instantaneous flow rate were also recorded., Results: Regardless of the aortic conduit, CEM valves showed a significantly lower gradient than SJME valves (p < 0.05), and a significantly larger effective orifice area (EOA) (p < 0.05); the latter parameter was unaffected for both valves, at an increasing pulse rate (p > 0.05). The maximum transvalvular flow velocity was significantly higher in the straight conduit for both valves (p < 0.05). With regards to diastole, the SJME valve showed the lowest regurgitant volume (p < 0.05). The leaflet coaptation time was significantly shorter for the SJME valve than for the CEM valve (p < 0.05), but when tested in a straight conduit it was shortened significantly for both valves (p < 0.05)., Conclusion: An absence of the sinuses of Valsalva may modify the diastolic and systolic behaviors of the tissue valve leaflets by reducing the time required for leaflet coaptation, and increasing the valve closing volume and maximum transvalvular flow velocity. It is speculated that these hydrodynamic changes may increase the working stress on the valve tissue, leading to possible premature structural valve deterioration.

Background and Aim of the Study: Previous studies have shown that the Carpentier-Edwards Magna (CEM) valve is an excellent bioprosthesis in terms of its systolic performance; indeed, it has been described as 'a stented valve with stentless performance'. However, valve performance is not only a matter of gradients; it is also necessary to evaluate the diastolic-phase performance. Previous in-vitro studies have shown that the CEM has an excessive total regurgitant volume. Hence, the study aim was to compare the hydrodynamics of the CEM, with the newly evolved version of this valve, the CEM Ease (CEME)., Methods: The CEM and CEME valves (both 21 mm) were tested in the aortic chamber (23 mm diameter) of the Sheffield pulse duplicator. The tests were carried out at increasing pulse rates (PR; 70-100 beats/min), and at each pulse rate the valve was tested at different stroke volumes (SVs; 45-65 ml). The forward-flow pressure drop, closing leakage volumes and effective orifice area (EOA) were recorded., Results: The CEM and CEME valves showed a comparable systolic-phase performance, there being no significant differences in terms of transvalvular gradient, EOA and stroke work loss, regardless of the PR and SV. In fact, the new CEME exhibited a significantly improved diastolic performance, with the total regurgitant volume being significantly lower, due especially to a reduced leakage volume and, to a lesser extent, a reduced closing volume., Conclusion: The study results indicated that the new CEME valve would maintain the excellent systolic performance of the previous CEM model, but with a significantly improved diastolic performance.

Background and Aim of the Study: The most effective method for decellularization of the intact porcine aortic root remains controversial. Additionally, the hydrodynamic effect that such treatment may have on aortic roots has never been previously investigated. The study aim was to compare the in-vitro hydrodynamic performances of intact porcine aortic roots, both before and after decellularization treatment., Methods: Fifteen fresh porcine aortic roots were tested in the aortic chamber of the Sheffield pulse duplicator (SPD). For study purposes, the roots were first sutured to a silicone aortic root and then hydrodynamically tested. After in-vitro testing, the fresh porcine aortic roots, while still fixed within the silicone root, were decellularized according to various protocols (TRI-COL, TRI-DOC, sodium dodecyl sulfate (SDS) 0.03%, and SDS 0.1%). After decellularization, the valve roots were re-tested, adopting identical testing conditions. Forward flow pressure drop, closing leakage volumes, effective orifice area (EOA), and stroke work loss were each monitored. Three roots, used as a control group, were tested in identical fashion before and after storage (without decellularization) for comparative purposes., Results: The TRI-COL- and TRI-DOC-treated porcine aortic roots showed significantly lower transvalvular gradients, lower stroke work loss, lower valve resistance, and higher EOA than fresh intact porcine roots. In contrast, SDS 0.1%-treated porcine aortic roots showed opposing results, with the transvalvular gradients, stroke work loss and valve resistance each higher, and the EOA lower, than pre-treatment values. SDS 0.03% treatment had no significant effect on the hydrodynamic performance. After decellularization in all treatment groups, the diastolic parameters, total regurgitant volume and valve closing volume were each non-significantly increased. The aortic roots used as a control group showed similar results before and after storage., Conclusion: Based on these results using the SPD, all treatments except for SDS 0.03% modified the systolic and diastolic functions of intact porcine aortic roots.

Background and Aim of the Study: In-vivo echocardiographic studies are limited by several confounding factors and technical pitfalls, and consequently the hypothetical differential hydraulic behavior between different prosthetic heart valves has not been identified. However, for surgeons it is essential to know the functional and geometric characteristics of the prostheses to be used. Herein, the in-vitro performance of two new supra-annular bileaflet prostheses--the Medtronic Advantage Supra and Sorin Bicarbon Overline--was compared with that of the 21-mm St. Jude Medical (SJM) Regent valve., Methods: Three high-performance, production-quality prostheses, including the sewing-ring cuffs, were tested in the aortic chamber of a Sheffield pulse duplicator. The sizes of the prostheses which fitted the 21-mm valve holder were: 21 mm Advantage Supra Medtronic; 19 mm SJM Regent, and 18 mm Sorin Bicarbon Overline. The tests were carried out at a fixed pulse rate (70 beats/min), and at increasing cardiac output (CO) of 2, 4, 5, and 7 l/min. Forward-flow pressure drop, total regurgitant volume, closing and leakage volumes, effective orifice area (EOA) and stroke work loss (SWL) were recorded while the valve was operated at each CO., Results: The SJM Regent and Sorin Bicarbon Overline valves each showed, at increasing CO, significantly lower mean and peak gradients. The calculated EOA and SWL were significantly better with the SJM Regent and Sorin Bicarbon Overline prostheses. The Medtronic Advantage Supra valve showed comparable results only while performing at 2 l/min CO. With regards to the regurgitant fraction, lowest values were observed with the Medtronic Advantage Supra valve., Conclusion: This hydrodynamic evaluation model allowed a comparison to be made of the efficiency of recently commercialized bileaflet prostheses, among which the older SJM Regent and the newer Sorin Bicarbon Overline valves demonstrated the best performances.

Background and Aim of the Study: The choice of aortic valve substitutes remains controversial. Malfunction and systemic valve complications affect the results of mechanical and tissue valves. Two devices--the Sorin Monocast (tilting disk) valve and the Hancock Standard valve were compared, the study aim being to determine whether the valve model is a marker or a causal influence of poor outcome after aortic valve replacement (AVR)., Methods: Between January 1970 and January 1984, patients aged < 70 years and operated on for aortic valve disease were selected. A total of 379 patients received either Sorin (group S) valves (n = 213; median age 51 years) or Hancock Standard (group HcK) valves (n = 192; median age 50 years) (p = NS). Total follow up was 2,471 patient-years (pt-yr) for group S and 2,368 pt-yr for group HcK. Follow up was 98% complete; median duration was 15 pt-yr for group S and 13.2 pt-yr for group HcK. Propensity matching for available patient intrinsic and operative risk factors was ultimately used to investigate whether biological or mechanical valve models impact upon outcome after aortic valve surgery. Patient survival was analyzed according to the 'intention to treat' principle., Results: The 30-day mortality was 7.5% for group S and 10.9% for group HcK (p = NS). The 19-year Kaplan-Meier freedom from valve-related mortality was 84% (group S) and 82% (group HcK) (p = NS), while overall survival was 42% (group S) and 35% (group HcK) (p = NS). Structural valve deterioration (SVD) was the major cause of reoperation in the HcK group. The 19-year freedom from all valve-related complications was 43% (group S) versus 19% (group HcK) (p = 0.0001). By propensity score, 61% of the valve replacements (247/405) were perfectly matched for available risk factors, with an equal distribution of risk covariates. When SVD and reoperation due to SVD were excluded, survival and freedom from all valve-related complications of the matched patients were identical between the prostheses under comparison., Conclusion: In this relatively young population, the Sorin valve showed a significantly lower valve-related complication rate than the Hancock Standard valve. The latter valve showed a significantly increasing rate of reoperation due to SVD, and thereby a relative inadequacy for use in younger patients. When analyzed according to an 'intention to treat' principle, the 19-year survival and freedom from valve-related complications of patients with the same propensity score for selection of either valve type were similar.

A 77-year-old woman was found accidentally to be in atrial fibrillation. Two-dimensional echocardiography revealed the presence of a mass attached to the anterior papillary muscle of the mitral valve. She was mildly symptomatic for dyspnea and asthenia. The patient was successfully operated on to excise the left ventricular mass and preserve the mitral valve apparatus. Morphological examination of the excised tissue led to a diagnosis of papillary fibroelastoma. Surgical treatment must be considered when such a tumor is diagnosed, even though asymptomatic, and especially if left-sided because of the high risk of systemic embolization.

There is general agreement that left-sided elastomas must be removed to avoid systemic complications. Right-sided localization is less risky and surgical treatment is not agreed upon. We report a case of surgical resected fibroelastoma of the tricuspid valve and discuss the indications to surgery by reviewing the literature on the few reported cases. We feel that, if surgery is timely, the tumor can be resected, thus preserving the native valve. This provides an opportunity to prevent possible right-sided complications due to increasing tumor size and embolization.

An acute type A aortic dissection, complicated by massive aortic regurgitation, was diagnosed in the case of a 32-year-old woman, thirty-three days post partum. Emergency operation (Cabrol II) was performed with an uneventful postoperative course. We draw attention to this high risk event, which is particularly apt to involve women within a short time after an otherwise uneventful pregnancy.

Seventy-two operative survivors of acute type A dissection between 1973 and 1993 had a complete follow up with a 16 years actuarial survival of 57% and a reoperation free actuarial survival of 34%. Follow up was 100% complete and covered a total of 500.6 patients-years with a median of seven years. Distal tear location (proximal, medium or distal aortic arch) with retrograde dissection toward the aortic valve was the single most important predictor of late mortality with a relative risk of 4.4 (70%CL 2.4-8.2) (p = 0.016). Mortality rate of patients with an aortic valve prosthesis was 6.2%/patient-year vs. 1.7/patient-year without aortic valve prosthesis, with a relative risk of 3.4 (70%CL 2.0-5.8) (p = 0.02). This finding could be due to confounding of variables related both to death and need of aortic valve replacement. Therefore a multivariate proportional hazard analysis, with mandatory inclusion of possible confounders, was done. It showed that patients with aortic valvular prosthesis had eight times higher risk (70% CL 2.7-24.2); prosthetic aortic valves and conservative aortic root procedures had an unconfounded relative risk of 14 times higher (70%CL 3.4-58.7) (P = 0.06), whereas patients with a composite conduit had a six times higher risk (70%CL 2.0-19.9) (p = 0.11). These findings support the attitude favoring a selective approach to aortic root repair and oppose standardized use of aortic valve prosthesis or composite conduit in acute type A dissection.