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1.
J Card Surg ; 32(11): 680-685, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29119598

RESUMEN

BACKGROUND: Stentless valves have long been considered the ideal valves in terms of hemodynamics. Recently, the Trifecta valve, a stented bioprosthesis with excellent fluid dynamic characteristics, has become available. The aim of the study was to compare the opening/closing pattern of the Freestyle stentless valve and the Trifecta valve with that of the native aortic valve. METHODS: A total of 12 patients with a Freestyle and 10 with a Trifecta valve were compared to normal native aortic valves in 12 control patients. Leaflet kinematics and hemodynamic parameters were obtained by echocardiographic M-mode and Doppler measurements. RESULTS: The control group displayed significantly longer Rapid Valve Opening Time (45 ± 7 ms) and Rapid Valve Closing Time (42 ± 9 ms) than Freestyle patients (Rapid Valve Opening Time: 32 ± 7 ms; Rapid Valve Closing Time: 31 ± 8 ms) and Trifecta patients (Rapid Valve Opening Time: 31 ± 7 ms; Rapid Valve Closing Time: 30 ± 8 ms) (P < 0.0001). The maximal leaflet displacement reached at the end of rapid valve opening was 16.7 ± 3.2 mm, 17.7 ± 2.3 mm, and 17.7 ± 5.3 mm (P = 0.42) in the Freestyle, Trifecta, and control groups, respectively. The total opening time was shorter in the control group (223 ± 25 ms) than in Freestyle (319 ± 61 ms) and Trifecta (324 ± 46 ms) patients (P < 0.0001). CONCLUSIONS: The Freestyle stentless valve was not superior to the Trifecta valve in terms of kinematics and functions more like a stented bioprosthesis.


Asunto(s)
Válvula Aórtica/fisiología , Válvula Aórtica/cirugía , Bioprótesis , Prótesis Valvulares Cardíacas , Stents , Anciano , Anciano de 80 o más Años , Válvula Aórtica/diagnóstico por imagen , Fenómenos Biomecánicos , Ecocardiografía Doppler , Femenino , Implantación de Prótesis de Válvulas Cardíacas , Hemodinámica , Humanos , Masculino
2.
J Artif Organs ; 19(4): 350-356, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27230086

RESUMEN

Pericardial and porcine stented aortic valves have different leaflet kinematics. To study the biomechanics of a prosthesis thoroughly, the in vitro setting is the most appropriate. The aim of our study was to find out whether the prosthesis design in which the pericardial sheet is outside the stent post might influence the opening and closing patterns of the leaflets. Four pericardial prostheses (Magna Ease [MG] 21, Trifecta [TRI] 21, Soprano-Armonia [SA] 20 and Mitroflow [MF] 23) that fitted aortic roots with a native annulus diameter of 2.1 cm were implanted and their leaflet kinematics was studied by a high-speed digital camera. In the opening phase, MG showed the shortest RVOT and the highest RVOVI, with values of 12 ± 2 and 209 ± 17 ms, respectively. The RVOT of MG was significantly shorter than that of MF (p < 0.01), but not than that of TRI (p = 0.286). Both TRI and SA showed similar opening patterns (TRI: RVOT of 15 ± 3 ms and RVOVI of 132 ± 25 ms; SA: 17 ± 2 ms and 126 ± 19 ms), without statistically significant difference. Conversely, MF showed the slowest profile, with an RVOT of 23 ± 3 ms and an RVOVI of 94 ± 8 ms (Table 1; Fig. 3). The opening/closing profile is not influenced by the position of the pericardial leaflets, but depends on other intrinsic structural characteristics related to the material used for the stent and leaflets. Moreover, the kinematics does not affect the valve performance. Table 1 Kinematics and hydrodynamic results, reported as means and standard deviations, evaluated over the tested heart samples TRI SA MG MF ANOVA TRI versus SA TRI versus MG TRI versus MF SA versus MG SA versus MF MG versus MF p Value p Value p Value p Value p Value p Value p Value ET (ms) 1.0 1.0 1.0 1.0 RVOT (ms) 15 ± 3 17 ± 2 12 ± 2 23 ± 3 <0.01 1.0 0.286 <0.01 0.03 <0.01 <0.01 SVCT (ms) 247 ± 14 231 ± 15 256 ± 26 241 ± 11 0.170 0.463 0.853 0.931 0.213 1.0 1.0 RVCT (ms) 35 ± 19 52 ± 13 32 ± 17 52 ± 4 0.07 0.474 1.0 0.494 0.236 1.0 0.247 TVCT (ms) 283 ± 10 283 ± 19 289 ± 10 293 ± 11 0.584 1.00 1.0 1.0 1.0 1.0 1.0 RVOVI (ms-1) 132 ± 25 126 ± 19 209 ± 17 94 ± 8 <0.01 0.959 <0.01 0.02 <0.01 0.07 <0.01 SVCVI (ms-1) -0.9 ± 0.3 -1.1 ± 0.4 -0.57 ± 0.1 -0.55 ± 0.1 <0.01 1.0 0.353 0.292 0.045 0.04 1.0 RVCVI (ms-1) -16 ± 4 -10 ± 2 -18 ± 6 -10 ± 1 <0.01 0.396 1.0 0.513 0.025 1.0 0.03 Δp (mmHg) 6.7 ± 3.6 10.6 ± 5.5 15.2 ± 7.9 10.7 ± 6.1 <0.01 0.01 <0.01 0.01 0.04 1.0 <0.01 EOA (cm2) 2.2 ± 1.2 1.7 ± 0.9 1.5 ± 0.8 1.7 ± 0.9 <0.01 0.03 <0.01 0.01 0.261 0.617 0.11 El  % 7.3 ± 1 11.9 ± 1 15.4 ± 2 11.8 ± 3 <0.01 <0.01 <0.01 <0.01 0.04 1.00 0.03 CO (L/min) 3.1 ± 0.4 2.8 ± 0.5 3.1 ± 0.3 3.0 ± 0.5 0.534 0.282 0.792 0.702 0.106 0.552 0.559 ET ejection time, RVOT rapid valve-opening time, SVCT slow valve-closing time, RVCT rapid valve-closing time, TVCT total valve-closing time, RVOVI rapid valve-opening velocity index, SVCVI slow valve-closing velocity index, RVCVI rapid valve-closing velocity index, Δp mean pressure drop, EOA effective orifice area, El % energy loss, CO cardiac output.


Asunto(s)
Válvula Aórtica , Bioprótesis/estadística & datos numéricos , Prótesis Valvulares Cardíacas/estadística & datos numéricos , Animales , Aorta , Fenómenos Biomecánicos , Gasto Cardíaco , Hemodinámica , Humanos , Hidrodinámica , Técnicas In Vitro , Pericardio/trasplante , Diseño de Prótesis , Stents , Porcinos
3.
J Heart Valve Dis ; 24(3): 360-7, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26901913

RESUMEN

BACKGROUND AND AIM OF THE STUDY: Aortic valve replacement in patients with a small aortic root may be associated to high residual gradients. In such patients, both stentless valves and aortic annulus enlargement can reduce these residual gradients. Several studies have reported that Trifecta valves yield very good hemodynamic results. The aim of the present study was to compare the hemodynamic performance of Trifecta vs. Freestyle valves at one year in patients with an aortic annulus ≤ 2.3 cm. METHODS: Between September 2011 and September 2013, 40 patients with a native aortic annulus diameter ≤ 2.3 cm and average age of 81 ± 4 years, were randomized to receive either a St-Jude Trifecta stented prosthesis (20 patients) or a Medtronic Freestyle stentless prosthesis (20 patients). RESULTS: No differences between Trifecta and Freestyle were found at one year in mean gradient s: 6.1 ± 3 mmHg and 6.6 ± 3 mmHg (p = 0.796); effective ori fice area: 1.82 ± 0.3 mmHg and 1.76 ± 0.4 mmHg (p = 0.676) or regression of left ventricular mass: - 25% ± 14 vs. -19% ± 16 (p = 0.204), respectively. Only moderate patient -pro sthesis mismatch was found, which affected 3 patient s in each group. CONCLUSION: At one year both stentless and stented prostheses yielded comparable hemodynamic results. These data suggest that Trifecta implantation is a valid means of avoiding patient -prosthesis mismatch in aortic valve replacement in elderly patients with a small native aortic annulus.


Asunto(s)
Válvula Aórtica/anatomía & histología , Válvula Aórtica/cirugía , Velocidad del Flujo Sanguíneo , Prótesis Valvulares Cardíacas , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/cirugía , Ecocardiografía Doppler , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Masculino , Estudios Prospectivos , Diseño de Prótesis , Ajuste de Prótesis
4.
J Card Surg ; 30(5): 400-4, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25756936

RESUMEN

BACKGROUND: Patients with a small aortic annulus, that is ≤ 23 mm, constitute a challenge for the surgeon, because they are at high risk of patient-prosthesis mismatch. Stentless valves provide better hemodynamic performance at rest and during exercise than stented valves, and are advocated in this group of patients. A new-generation stented valve, the Trifecta (St. Jude), has recently become available with improved hemodynamics. The aim of this study was to compare the hemodynamic performance of Freestyle (Medtronic) and Trifecta at rest and during exercise in patients with a small aortic annulus. METHODS: From September 2012 to September 2014, 22 patients with a native aortic annulus ≤ 23 mm underwent ergometric stress testing one year after aortic valve replacement with either a Trifecta (12 patients) or a Freestyle (10 patients) bioprosthesis as part of a randomized study. RESULTS: The mean gradient at rest was 6.0 ± 2.3 mmHg for Trifecta and 4.3 ± 3.5 for Freestyle (p = 0.213). The mean gradient at peak of exercise was 9.7 ± 3.4 mmHg for Trifecta and 7.4 ± 5 mmHg for Freestyle (p = 0.243). No significant differences were found between the two prostheses regarding other hemodynamic parameters: effective orifice area, velocity index, and performance indexes. CONCLUSION: Both the stented Trifecta and stentless Freestyle prostheses provide excellent hemodynamic results during physical stress in patients with a small aortic annulus. Our study confirms that Trifecta implantation results in low gradients at rest and during exercise and that the performance of Trifecta is similar to that of a stentless valve.


Asunto(s)
Válvula Aórtica/fisiología , Ejercicio Físico/fisiología , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Prótesis Valvulares Cardíacas , Hemodinámica , Anciano , Anciano de 80 o más Años , Válvula Aórtica/cirugía , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Evaluación de Resultado en la Atención de Salud , Diseño de Prótesis
5.
J Heart Valve Dis ; 23(5): 633-41, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25799714

RESUMEN

BACKGROUND AND AIM OF THE STUDY: Aortic valve replacement (AVR) in patients with a small aortic root is often associated with some degree of obstruction and residual gradients. Stentless valves display better hemodynamic performance than stented valves, and might be ideal in patients with a small aortic annulus. A new stented bioprosthesis, the Trifecta valve, has recently become available and has yielded interesting early results. The study aim was to compare the hemodynamic performance of the Trifecta valve with that of the Freestyle valve in patients with an aortic annulus ≤ 2.3 cm. METHODS: Between September 2011 and September 2013, a total of 40 patients with pure aortic stenosis and native aortic annulus diameter ≤ 2.3 cm was randomized to receive either a St. Jude Medical Trifecta stented prosthesis (n = 20) or a Medtronic Freestyle stentless prosthesis (n = 20). Hemodynamics results were compared between the two groups on discharge from hospital. RESULTS: The Trifecta valve showed slightly better hemodynamics, with peak gradients of 11 ± 5 mmHg and 17 ± 9 mmHg (p = 0.009), and mean gradients of 5.5 ± 3 mmHg and 7.5 ± 4 mmHg (p = 0.06) for the Trifecta and Freestyle valves, respectively. The average indexed effective orifice area (EOAi) was 1.14 ± 0.23 cm2/m2 and 1.09 ± 0.20 cm2/m2 (p = 0.520) for the Trifecta and Freestyle, respectively. Patient-prosthesis mismatch (PPM) occurred in two patients of the Freestyle group, and in three patients of the Trifecta group. CONCLUSION: In the present study, the stentless and stented prostheses each yielded comparable and excellent early hemodynamics results. The data obtained suggest that Trifecta valve implantation is a valid means of avoiding PPM after AVR in patients with a small native aortic annulus.


Asunto(s)
Estenosis de la Válvula Aórtica/patología , Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/patología , Válvula Aórtica/cirugía , Bioprótesis , Prótesis Valvulares Cardíacas , Hemodinámica , Anciano de 80 o más Años , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/fisiopatología , Femenino , Implantación de Prótesis de Válvulas Cardíacas , Humanos , Masculino , Estudios Prospectivos , Diseño de Prótesis , Stents , Resultado del Tratamiento , Ultrasonografía
6.
Semin Thorac Cardiovasc Surg ; 32(4): 635-643, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31356867

RESUMEN

In Sleeve procedure, the leaflets-sinus unit is maintained. We hypothesized that this feature partially preserves aortic root (AR) dynamics and leaflets kinematics and limits tensions in the leaflets. We tested our hypothesis based on in vivo and computational assessment of leaflets and AR dynamics. AR and aortic leaflet kinematics was assessed by transthoracic echocardiography in 10 patients treated with the Sleeve procedure and in 10 healthy patients. Numerical calculations with the Finite Element Method were performed to support the analysis of the clinical results and provide a better understanding of the behavior of the AR treated via the Sleeve procedure. Echocardiographic evidence showed that AR expansion in the Sleeve group was partially preserved as compared to the Control group (2.9 ± 2.5% vs 7.7 ± 6.3%, P = 0.038) and of the sinotubular junction (2.9 ± 1.5% vs 7.3 ± 3.8%, P = 0.003), and significantly preserved at the Valsalva sinuses level (6.7 ± 2.6% vs 9.5 ± 4.3%) with not statistically significant differences (P = 0.11). In none of the cardiac phases, differences in aortic valve leaflets kinematics were measured between the 2 groups; computational results were rather consistent with this evidence. Computational results well matched echocardiographic evidences, allowing for their mechanistic interpretation. Near-normal opening and closing characteristics can be accomplished by a technique that preserves the shape and the dynamics of the Valsalva sinuses. Whether the substantial preservation of the AR distensibility and leaflets kinematics observed in this study will favorably affect long-term valve durability it remains to be ascertained.


Asunto(s)
Aorta/cirugía , Aneurisma de la Aorta/cirugía , Insuficiencia de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Ecocardiografía , Modelos Cardiovasculares , Modelación Específica para el Paciente , Procedimientos Quirúrgicos Vasculares , Adulto , Aorta/diagnóstico por imagen , Aorta/fisiopatología , Aneurisma de la Aorta/diagnóstico por imagen , Aneurisma de la Aorta/fisiopatología , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiopatología , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/fisiopatología , Fenómenos Biomecánicos , Estudios de Casos y Controles , Femenino , Análisis de Elementos Finitos , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Recuperación de la Función , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos
7.
J Cardiovasc Surg (Torino) ; 61(2): 250-255, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31985188

RESUMEN

BACKGROUND: Patients with aortic root ectasia and bicuspid aortic valve benefit of the treatment with aortic valve sparing procedure, with excellent long-term results. The Sleeve-procedure is one of the options in patients with aortic root diseases and it might be suitable for patients with a bicuspid valve. METHODS: From October 2006 to December 2018, 42 consecutive patients with bicuspid aortic valve and aortic root ectasia/aneurysm, with or without aortic regurgitation, were surgically treated with the Sleeve-procedure. RESULTS: In 20 patients (48%) leaflets surgery was necessary and consisted of raphe mobilization/resection in 17 patients, plication of both leaflets in 2 patients and a two-commissures resuspension in 1 patient. During a mean clinical follow-up time of 4.4±3.1 years, the survival rate was 100%, 1 patient required a reoperation at 6.1 years postoperatively, with an overall freedom from reoperation of 94±5%. The rest of the patients (41/42), had no more than mild residual aortic valve regurgitation. With a mean follow-up of 4.3±1.7 years the magnetic resonance imaging performed in 26 patients, did not show signs of aortic wall herniation through the key-holes or persisting creases of the aortic wall inside the prosthesis. CONCLUSIONS: Patients with aortic root disease and bicuspid aortic valve may be treated with Sleeve technique with excellent midterm results. However, a longer follow-up is required before drawing any solid conclusion.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Insuficiencia de la Válvula Aórtica/cirugía , Válvula Aórtica/anomalías , Procedimientos Quirúrgicos Cardíacos/métodos , Enfermedades de las Válvulas Cardíacas/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Monitoreo Fisiológico/métodos , Adulto , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/mortalidad , Enfermedad de la Válvula Aórtica Bicúspide , Procedimientos Quirúrgicos Cardíacos/mortalidad , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Humanos , Imagen por Resonancia Cinemagnética/métodos , Masculino , Persona de Mediana Edad , Tratamientos Conservadores del Órgano , Estudios Retrospectivos , Medición de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
8.
J Cardiothorac Surg ; 14(1): 94, 2019 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-31113456

RESUMEN

BACKGROUND: Sparing Aortic Valve procedure requires to reproduction of the geometry of the physiologic anatomy of the aortic root. Thus, the materials adopted may make a difference. CARDIOROOT is a one-piece collagen-coated woven vascular graft with pseudo-sinuses, which was designed for use in the treatment of aortic root disease. We report the results of a prospective, multicenter, observational post-market surveillance study evaluating the safety and performance of the CARDIOROOT in patients requiring aortic root surgery. METHODS: Patients with aortic root disease suitable for treatment with a vascular graft with pseudo-sinuses CARDIOROOT graft were eligible for participation. The enrolled patients were assessed intraoperatively, post-operatively, at discharge and at 1-year. Sites assessed complications at each visit, and recorded any reported adverse events. The study endpoint was mortality and complications through 1-year post-procedure. RESULTS: Fifty-two patients were enrolled from 6 European centers. All procedures were technically successful. Operative mortality was 1.9%: one patient suffered hemorrhagic shock unrelated to the graft 1 day following surgery. At 1-year follow-up the survival rate was 96.2%, with a late death due to pneumonia 5 months post-procedure. Eleven serious adverse events occurred in 7 patients, which included cardiac complications (pericardial effusion, myocardial infarction and ventricular arrhythmia), infection (pericardial infection, deep sternal infection and superficial sternal infection), vascular disorders, including hemorrhagic shock and pleural effusion requiring drainage. Nine of the 11 events were deemed procedure-related by the local investigator, and all were deemed unrelated to the device. There were no reports of graft-related adverse events, infection, occlusion or graft failure. CONCLUSIONS: The results of this 1-year follow-up study showed that the CARDIOROOT vascular graft is safe and effective for the treatment of aneurysmal aortic root in immediate and mid-term follow-up. However, longer term follow-up is needed before conclusions can be made on the long-term safety and effectiveness. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01609270. Registered 31 May 2012.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/instrumentación , Adulto , Anciano , Aneurisma de la Aorta Torácica/mortalidad , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Vigilancia de Productos Comercializados , Estudios Prospectivos , Diseño de Prótesis , Tasa de Supervivencia , Adulto Joven
9.
ASAIO J ; 64(1): 86-90, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28475560

RESUMEN

Hydrodynamic performance of stented bioprostheses is far below that of the native valve. One of the reasons is that the internal diameter of the prosthesis is usually smaller than that of the native valve. However, other valve characteristics are also important in generating the pressure drop. We aimed to assess, in an ex vivo pulsatile mock loop, the hydrodynamic behavior of two bioprostheses, Trifecta and Mitroflow, to ascertain which geometric terms are limiting factors in hydrodynamic performance. At stroke volumes between 30 and 60 ml, Trifecta showed lower pressure drop, energy dissipation and valve resistance, and greater effective orifice area. This trend was overturned at higher stroke volumes, with Mitroflow slightly outperforming Trifecta. The geometric determinants were consistent with these results. Trifecta achieved its maximum opening area already at the lowest stroke volumes, featuring a divergent shape at the systolic peak. Mitroflow showed a complex opening pattern, featuring a convergent shape at the systolic peak for lower stroke volumes, while reaching its maximum opening area at higher stroke volumes, with a divergent shape. The two bioprostheses, although similar in design, displayed different biomechanical behaviors. The internal diameter of each bioprosthesis did not show to be strictly correlated with its hydrodynamic characteristics.


Asunto(s)
Válvula Aórtica/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Prótesis Valvulares Cardíacas/estadística & datos numéricos , Hemodinámica/fisiología , Animales , Válvula Aórtica/fisiopatología , Bioprótesis/estadística & datos numéricos , Hidrodinámica , Pericardio/cirugía , Diseño de Prótesis , Stents , Volumen Sistólico/fisiología , Porcinos
10.
Case Rep Surg ; 2017: 3831749, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28203474

RESUMEN

Mediastinal radiation is commonly used to treat Hodgkin's and non-Hodgkin's lymphoma, lung and breast cancer. Cardiac complications after radiation therapy are well described, although rare. A large spectrum of injuries can occur, causing long term morbidity among survivors. We describe a case of post-actinic ascending aortic wall thickening that prevented saphenous vein proximal anastomosis and was successfully managed with aortic no-touch off-pump coronary artery bypass grafting (OPCAB), 25 years after radiation therapy for Hodgkin's lymphoma.

11.
Ann Thorac Surg ; 103(5): 1451-1459, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27756469

RESUMEN

BACKGROUND: Aortic root aneurysm can be treated with valve-sparing procedures. The David and Yacoub techniques have shown excellent long-term results but are technically demanding. Recently, a new and simpler procedure, the Sleeve technique, was proposed with encouraging results. We aimed to quantify the biomechanics of the initially aneurysmal aortic root (AR) after the Sleeve procedure to assess whether it induces abnormal stresses, potentially undermining its durability. METHODS: Two finite element (FE) models of the physiologic and aneurysmal AR were built, accounting for the anatomical asymmetry and the nonlinear and anisotropic mechanical properties of human AR tissues. On the aneurysmal model, the Sleeve and David techniques were simulated based on the corresponding published technical features. Aortic root biomechanics throughout 2 consecutive cardiac cycles were computed in each simulated configuration. RESULTS: Both sparing techniques restored physiologic-like kinematics of aortic valve (AV) leaflets but induced different leaflets stresses. The time course averaged over the leaflets' bellies was 35% higher in the David model than in the Sleeve model. Commissural stresses, which were equal to 153 and 318 kPa in the physiologic and aneurysmal models, respectively, became 369 and 208 kPa in the David and Sleeve models, respectively. CONCLUSIONS: No intrinsic structural problems were detected in the Sleeve model that might jeopardize the durability of the procedure. If corroborated by long-term clinical outcomes, the results obtained suggest that using this new technique could successfully simplify the surgical repair of AR aneurysms and reduce intraoperative complications.


Asunto(s)
Aorta Torácica/fisiopatología , Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/fisiopatología , Aneurisma de la Aorta Torácica/cirugía , Fenómenos Biomecánicos/fisiología , Análisis de Elementos Finitos , Simulación por Computador , Humanos , Modelos Cardiovasculares , Dinámicas no Lineales , Seno Aórtico/fisiopatología , Seno Aórtico/cirugía
12.
Diabetes Care ; 25(3): 530-6, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11874942

RESUMEN

OBJECTIVE: This study examined the metabolic effects of heart transplantation in patients in end-stage cardiac failure. RESEARCH DESIGN AND METHODS: A total of 18 patients after heart transplantation for end-stage heart disease (age 47 +/- 3 years; transplant age 5.5 +/- 1.5 years; BMI 25.8 +/- 0.8 kg/m(2); cyclosporin A 4.2 +/- 0.6 mg/[kg.day]; azathioprine 0.87 +/- 0.31 mg/[kg.day]), 12 patients with type 2 diabetes (D-Tx), and 6 patients without type 2 diabetes (Tx) were studied by means of 1) an oral glucose tolerance test (OGTT) to assess the beta-cell secretory response, 2) a euglycemic-hyperinsulinemic (1 mU/[kg.min]) clamp combined with indirect calorimetry and a primed continuous infusion of [6,6-2H2]glucose and [1-13C]leucine to measure postabsorptive and insulin-stimulated carbohydrate and protein metabolism, and 3) 1H-NMR spectroscopy of the calf muscles to measure intramyocellular triglyceride (IMCL) content. The patients were selected from 480 transplant patients in whom there was a 6% prevalence of type 2 diabetes. Five healthy subjects matched for anthropometric parameters served as control subjects (CON). RESULTS: Tx had postabsorptive and insulin-stimulated glucose, leucine, and free fatty acid metabolism, as well as IMCL content, similar to that of CON. D-Tx were characterized by a reduced secretory response during the OGTT and peripheral insulin resistance with respect to glucose metabolism, which was paralleled by increased plasma free fatty acid concentrations and IMCL content. A defective insulin-dependent suppression of the endogenous leucine flux (index of proteolysis) was also evident during the clamp in D-Tx. CONCLUSIONS: Heart transplantation, notwithstanding the immunosuppressive therapy, was characterized by a normal postabsorptive and insulin-stimulated glucose, leucine, and free fatty acid metabolism in Tx. In contrast, insulin resistance with respect to glucose, free fatty acids, and protein metabolism was present in D-Tx regardless of whether diabetes was preexisting or consequent to heart transplantation.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus/metabolismo , Metabolismo Energético , Trasplante de Corazón/fisiología , Lípidos/sangre , Adulto , Albuminuria/epidemiología , Péptido C/sangre , Colesterol/sangre , Diabetes Mellitus/sangre , Diabetes Mellitus/fisiopatología , Neuropatías Diabéticas/epidemiología , Femenino , Estudios de Seguimiento , Glucagón/sangre , Técnica de Clampeo de la Glucosa , Humanos , Insulina/sangre , Masculino , Persona de Mediana Edad , Conducción Nerviosa/fisiología
13.
J Thorac Cardiovasc Surg ; 149(3): 912-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25466861

RESUMEN

BACKGROUND: The in vivo hemodynamic performance of a bioprosthesis implanted in an aortic position is affected by the characteristics of the prosthesis and the sizing strategy adopted. Recently, it has been hypothesized that the type of suture used to implant the prosthesis might influence hemodynamics. METHODS: Bioprostheses with labeled sizes of 19 mm and 21 mm were implanted in 2 groups of 5 porcine aortic roots, with native annuli of 19 mm and 21 mm, by means of 2 different suture techniques: simple interrupted and noneverting mattress with pledgets. The aortic roots were tested in an in vitro mock loop. The stroke volume imposed by the mock loop was set at 40 mL, and was increased by steps of 15 mL until a stroke volume of 100 mL was attained. Main fluid-dynamic parameters were analyzed. RESULTS: At each level of stroke volume, ie, 40 mL, 55 mL, 70 mL, 85 mL, and 100 mL, the mean and peak pressure drops were significantly greater with the noneverting mattress suture with pledgets than with the simple interrupted suture. The effective orifice area behaved accordingly, being significantly smaller in the former case. CONCLUSIONS: Our data show that the type of suture technique can influence bioprosthesis performance and that it is reasonable to assume that this is especially true in small annuli (≤ 21 mm). Thus, to optimize prosthesis performance and reduce the incidence of patient-prosthesis mismatch, the role of the suture technique should not be disregarded.


Asunto(s)
Válvula Aórtica/cirugía , Bioprótesis , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Prótesis Valvulares Cardíacas , Hemodinámica , Técnicas de Sutura , Animales , Válvula Aórtica/patología , Válvula Aórtica/fisiopatología , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Modelos Animales , Complicaciones Posoperatorias/patología , Complicaciones Posoperatorias/fisiopatología , Diseño de Prótesis , Estrés Mecánico , Volumen Sistólico , Técnicas de Sutura/efectos adversos , Porcinos
14.
Ann Thorac Surg ; 99(4): 1228-33, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25662437

RESUMEN

BACKGROUND: The aim of this retrospective study was to evaluate our experience of using a simplified aortic valve sleeve procedure to treat aortic root ectasia and aneurysms with or without aortic regurgitation. In experienced hands, 2 aortic valve-sparing procedures, ie, Yacoub and David, have yielded excellent long-term results in the treatment of aortic root aneurysms, with or without aortic regurgitation. However, these techniques are demanding and not widely used. Recently, a new and simplified valve-sparing technique, named "sleeve procedure," has been proposed, and has yielded encouraging early results. METHODS: Ninety consecutive patients with aortic root aneurysms underwent sleeve procedures from October 2006 to October 2012. Follow-up data (clinical 100% complete and echocardiographic 93% complete) were acquired from our outpatient clinic or from the referring cardiologist. RESULTS: The mean age of the patients was 61.5 ± 12.5 years, 79% were male, 16 (18%) had a bicuspid valve, 3 had Marfan syndrome, and 2 had aortic dissection. Over a mean clinical follow-up of 34 ± 19 months, 2 patients died from noncardiac causes and 1 was reoperated on for the recurrence of aortic regurgitation. On follow-up echocardiography after a mean of 18 ± 9 months, aortic regurgitation was absent/negligible, mild or moderate in 62%, 37%, and 1% of patients, respectively, and the diameters of the annulus, Valsalva sinuses, and sinotubular junction were 27.3 + 2.2, 37.0 + 3.4, and 30.6 + 3.1 mm, respectively. CONCLUSIONS: Our encouraging early and medium term results suggest that the sleeve procedure is a safe and effective aortic valve-sparing technique for the treatment of aortic root ectasia and aneurysm. However, longer follow-up is needed in order to draw definitive conclusions.


Asunto(s)
Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Válvula Aórtica/cirugía , Anuloplastia de la Válvula Cardíaca/métodos , Tratamientos Conservadores del Órgano/métodos , Anciano , Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/patología , Válvula Aórtica/diagnóstico por imagen , Estudios de Cohortes , Dilatación Patológica/patología , Dilatación Patológica/cirugía , Ecocardiografía Doppler/métodos , Circulación Extracorporea , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Seguridad del Paciente , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/fisiopatología , Estudios Retrospectivos , Medición de Riesgo , Esternotomía/métodos , Técnicas de Sutura , Factores de Tiempo , Resultado del Tratamiento
15.
Eur J Cardiothorac Surg ; 47(2): e62-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25414428

RESUMEN

OBJECTIVES: Small-sized aortic bioprostheses may cause high postoperative gradients. In clinical practice, it is difficult to compare bioprostheses from different manufactures, owing to the discrepancy between the true size and the nominal size of the prosthesis and the inter-patient variability in aortic root characteristics. In vitro studies provide accurate data, and using a system in which it is possible to implant bioprostheses in a true aortic root should enable a fair comparison to be made. The present study compared the four most widely used pericardial stented bioprostheses from different manufacturers surgically implanted in small annulus, to detect any differences in their fluid-dynamic performance. METHODS: The four types of bioprostheses, each implanted in a randomized sequence in eight porcine aortic roots, with a native annulus of 2.1 cm, were tested in a mock loop at 65 ml of stroke volume by calculating hydrodynamic parameters, namely mean pressure drop and effective orifice area, performance index, valve resistance and % of energy loss. The prostheses that fitted the aortic root after sizing were as follows: a Magna Ease 21, a Trifecta 21, a Soprano-Armonia 20 and a Mitroflow 23. RESULTS: Effective orifice areas were 1.57 ± 0.2, 1.77 ± 0.2, 2.3 ± 0.3 and 1.75 ± 0.2 cm(2) (P < 0.001) for Magna Ease, Mitroflow, Trifecta and Soprano-Armonia, respectively. The mean gradients were 13.2 ± 3, 10.2 ± 3, 6.1 ± 2 and 9.6 ± 2 mmHg (P < 0.001) for Magna Ease, Mitroflow, Trifecta and Soprano-Armonia, respectively. The performance indices were 0.50 ± 0.06, 0.63 ± 0.08, 0.89 ± 0.13 and 0.56 ± 0.07 (P < 0.001) for Magna Ease, Mitroflow, Trifecta and Soprano-Armonia, respectively. The valve resistance, expressed in (dyn*s/cm(5)), was 69 ± 16, 55 ± 13, 33 ± 10 and 51 ± 11 (P < 0.001) for Magna Ease, Mitroflow, Trifecta and Soprano-Armonia, respectively. The percent of energy loss was 13.5 ± 0.5, 10.7 ± 2.5, 6.6 ± 1.6, 10.9 ± 1.8 (P < 0.001) for Magna Ease, Mitroflow, Trifecta and Soprano-Armonia, respectively. CONCLUSION: Our study combined the fluid-dynamic reproducibility of the in vitro study with, by using porcine aortic roots, the specificity of surgery. The results confirmed that bioprostheses are inherently obstructive compared with the native aortic valve and showed that bioprostheses with the pericardium outside the stent are more efficient.


Asunto(s)
Válvula Aórtica/cirugía , Bioprótesis , Prótesis Valvulares Cardíacas , Modelos Cardiovasculares , Pericardio/cirugía , Animales , Hemodinámica , Diseño de Prótesis , Porcinos
16.
J Cardiothorac Surg ; 10: 169, 2015 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-26589286

RESUMEN

BACKGROUND: The Trifecta aortic bioprosthesis (St. Jude Medical, Inc., St. Paul, MN, USA) is a stented pericardial heart valve with excellent preliminary results. Aim of the study was to evaluate its early clinical and hemodynamic performances in a multicenter regional registry. METHODS: Between January 2011 and June 2012, 178 consecutive patients undergoing aortic valve replacement with the Trifecta bioprosthesis were prospectively enrolled at 9 Italian centers. Clinical and echocardiographic data were collectedat discharge, 6-months and at 1-year postoperatively. RESULTS: The average age was 75.4 ± 7.7 years,and 95 (53 %) were men. Indication for valve replacement included stenosis in 123 patients (69 %), mixed lesions in 25 (14 %), and regurgitation in 30 (17 %). Ninety-three (52 %) patients were in NYHA functional class III/ IV. Hospital mortality accounted for 5 (2.8 %) patients. No valve-related perioperative complications were encountered. Median follow-up was 20.5 months (range: 1-34). Early (≤6 months) complications included one thromboembolic event, one major bleeding, and 3 endocarditis (2 explants). Two late (>6 months) thromboembolic events and two endocarditis (1 explant) were registered. No valve thrombosis or structural deterioration were observed after discharge. At 30-months, freedom from all-cause mortality was 87 %, freedom from valve-related mortality 99.4 %, freedom from endocarditis 97.5 %, and freedom from valve explants 98 %. At 1-year, mean gradients ranged from 8 to 16 mmHg, and effective orifice area indexes from 1.0 to 1.2 cm(2)/m(2) for valve sizes from 19 to 27 mm, respectively. No patients had severe prosthesis-patient mismatch. CONCLUSIONS: Trifecta bioprosthesis provided favourable clinical and hemodynamic results over time.


Asunto(s)
Insuficiencia de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Bioprótesis , Prótesis Valvulares Cardíacas , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Diseño de Prótesis , Factores de Tiempo
17.
J Thorac Cardiovasc Surg ; 127(2): 555-62, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14762368

RESUMEN

OBJECTIVE: The clinical features and outcomes of patients undergoing heart transplantation after a failed Fontan operation are still debated. The aim of this study was to retrospectively evaluate our experience in 14 patients undergoing heart transplantation after previous Fontan-type operations. METHODS: From 1990 to 2002, 14 patients underwent heart transplantation in our institution after a previous Fontan procedure. The mean age at the time of the Fontan operation and at transplantation was 7.3 +/- 2.8 and 17.2 +/- 6.3 years, respectively. The indication for transplantation was protein-losing enteropathy in 7 patients, arrhythmia with ventricular dysfunction in 5 patients, and heart failure in 2 patients. All patients received basic immunosuppressive therapy with cyclosporine (INN: ciclosporin) and azathioprine without induction therapy or maintenance steroids. RESULTS: Two hospital deaths occurred: one patient died on the fifth postoperative day of graft failure, and the second died on the 17th postoperative day after an acute neurologic event. Two patients died later, one 23 months after transplantation of acute rejection and the other after 90 months of chronic rejection and endocarditis. One patient underwent successful reintervention 2 years after heart transplantation for pulmonary vein obstruction. The 10 surviving patients are in New York Heart Association class I, with a mean follow-up of 64.5 +/- 42 months. One of them was delivered of a healthy baby 5 years after transplantation. Patients with protein-losing enteropathy reached a normal protein level within a mean of 10 months (range, 6-18 months) after transplantation. Four patients required a temporary administration (3-6 months) of oral steroid therapy for recurrent rejection episodes. Currently, 7 patients are taking cyclosporine, and 3 are taking cyclosporine and azathioprine. The actuarial survival at 1, 5, and 10 years was 86% +/- 9%, 77% +/- 12%, and 62% +/- 17%, respectively. CONCLUSION: Heart transplantation is a good option for patients with a failing Fontan operation. We documented the reversibility of protein-losing enteropathy in all patients. No mortality caused by surgical complications was observed.


Asunto(s)
Procedimiento de Fontan , Trasplante de Corazón , Ácido Micofenólico/análogos & derivados , Adolescente , Adulto , Azatioprina/administración & dosificación , Biomarcadores/sangre , Proteínas Sanguíneas/metabolismo , Gasto Cardíaco Bajo/mortalidad , Gasto Cardíaco Bajo/cirugía , Niño , Preescolar , Creatinina/sangre , Ciclosporina/administración & dosificación , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Cardiopatías Congénitas/mortalidad , Cardiopatías Congénitas/cirugía , Humanos , Inmunosupresores/administración & dosificación , Italia , Tiempo de Internación , Masculino , Ácido Micofenólico/administración & dosificación , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/terapia , Reoperación , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
18.
Ann Thorac Surg ; 77(1): 314-7, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14726087

RESUMEN

Takayasu's arteritis (TA) is a chronic large vessel vasculitis, first described in 1908 by the Japanese ophthalmologist Takayasu, affecting more frequently young women. The typical lesions represented by aneurysmatic dilatation or obliteration, and narrowing of the arterial lumen may pose technical difficulties as well as demanding decision making for treatment. Since Jarvell first described aortic regurgitation in TA in 1954, unresolved problems still remain for aortic valve replacement, particularly because of the young age of these patients. We report the case of a 28-year-old woman, with a known history of TA, referred to our department.


Asunto(s)
Válvula Aórtica/trasplante , Arteritis de Takayasu/cirugía , Adulto , Femenino , Humanos , Procedimientos Quirúrgicos Vasculares/métodos
19.
Ann Thorac Surg ; 74(6): 2016-21, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12643389

RESUMEN

BACKGROUND: Stentless bioprostheses and homografts show better hemodynamic profiles compared with conventional stented bioprostheses and mechanical valves. Few data are available on stentless aortic valve implantation for patients with severe left ventricular dysfunction. The aim of this retrospective study was to assess the potential benefits of stentless aortic valve implantation for patients undergoing isolated aortic valve replacement with left ventricular ejection fraction < or = 35%. METHODS: From November 1988 through March 2000, 53 patients (45 men and 8 women, aged 64.2 +/- 15.2 years) with a LVEF < or = 35% (mean EF, 28.7 +/- 5.4%) underwent isolated, primary aortic valve replacement for chronic aortic valve disease. Twenty patients received stentless aortic valves and 33 patients received conventional stented bioprostheses and mechanical valves. Predictive factors for LVEF recovery at echocardiographic follow-up (36.2 +/- 32.1 months) were analyzed by simple and multiple regression analysis. RESULTS: There were no significant differences between groups in early and late mortality. Stentless aortic valve implantation required a longer aortic cross-clamp time (p = 0.037). The stentless aortic valve group showed a better LVEF recovery (p = 0.016). Stentless aortic valves had a larger indexed effective orifice area compared with conventional stented bioprostheses and mechanical valves (p < 0.0001). A smaller indexed effective orifice area (p = 0.0008), chronic obstructive pulmonary disease (p = 0.015), and implantation of a conventional stented bioprosthesis or mechanical valve (p = 0.016) were related to reduced LVEF recovery by univariate analysis. A larger indexed effective orifice area (p = 0.024) was an independent predictive factor for a better LVEF recovery by multivariate analysis. CONCLUSIONS: Stentless aortic valve implantation for patients with severe left ventricular dysfunction, even if technically more demanding, is a safe procedure that warrants a larger indexed effective orifice area leading to an enhanced LVEF recovery.


Asunto(s)
Válvula Aórtica , Prótesis Valvulares Cardíacas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Estudios Retrospectivos , Volumen Sistólico , Función Ventricular Izquierda
20.
Ital Heart J Suppl ; 3(7): 728-37, 2002 Jul.
Artículo en Italiano | MEDLINE | ID: mdl-12187633

RESUMEN

BACKGROUND: Aortic valve surgery for infective endocarditis is still a high-risk procedure and the optimal valve substitute remains controversial. The aim of this study was to evaluate the results of our experience using homografts in the treatment of native (NVE) or prosthetic valve endocarditis (PVE). METHODS: Between May 1992 and December 2000, 37 patients with NVE and 16 patients with PVE underwent aortic valve replacement with homografts for infective endocarditis. In the two groups of patients the mean age was 57 and 61 years and 38% and 50% were in NYHA functional class IV or V. At the time of surgery, 28 patients had gross vegetations, 23 single or multiple abscess cavities, 3 ventricular septal perforations, and 9 mitral valve endocarditis. Homograft insertion was performed in a subcoronary position in 47 cases and as a root replacement in 6 cases. In 21 cases associated surgical procedures were also performed. RESULTS: Follow-up was 94% complete at a mean of 56 months after valve replacement. There were 1 hospital and 7 delayed deaths; the actuarial survival at 5 years was 85.5 +/- 6% for NVE and 80.8 +/- 10% for PVE. Endocarditis recurred early in 2 cases (both with fungal infection) and late in 3 cases with an endocarditis-free 5-year period of 87.1 +/- 5%. Delayed echocardiography demonstrated aortic incompetence classified as grade II in 40 cases and as grade III and IV in 2 cases. Thirty-nine patients are in NYHA class I and 3 in class II or III. CONCLUSIONS: On the basis of our experience we can conclude that in case of acute endocarditis, if the results of surgery are to be optimized, an early diagnosis and aggressive medical therapy need to be combined with earlier surgical referral. In the presence of NVE without annular abscesses the likelihood of recurrent endocarditis is probably more likely to depend on the infective organism than on the type of valve implanted. Our results support the suggestion that in the presence of NVE with extensive annular abscesses or in case of PVE the homograft valve is the replacement device of choice.


Asunto(s)
Válvula Aórtica/trasplante , Endocarditis Bacteriana/cirugía , Prótesis Valvulares Cardíacas , Infecciones Relacionadas con Prótesis/cirugía , Análisis Actuarial , Adolescente , Adulto , Anciano , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Bacterias/aislamiento & purificación , Endocarditis Bacteriana/microbiología , Endocarditis Bacteriana/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Válvula Mitral , Cuidados Posoperatorios , Complicaciones Posoperatorias , Recurrencia , Reoperación , Factores de Tiempo , Trasplante Homólogo
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