Hand-sewn expanded polytetrafluoroethylene valved conduit for right ventricular outflow tract reconstruction / 中南大学学报(医学版)

OBJECTIVES@#Due to the lack of large-sized pulmonary valved conduit products in clinical practice, hand-sewn expanded polytetrafluoroethylene (ePTFE) valved conduit has been used for right ventricular outflow tract (RVOT) reconstruction in many heart centers around the world. This study aims to summarize the early results of the ePTFE valved conduit and the sewing technology of the conduit in combination with the latest progress, and to provide a reference for the application of ePTFE valved conduit.@*METHODS@#A total of 21 patients using ePTFE valved conduit for RVOT reconstruction in the Second Xiangya Hospital, Central South University from October 2018 to October 2020 were prospectively enrolled in this study. The age at the implantation of the conduit was 4.3 to 43.8 (median 15.1) years old, with weight of (38.9±4.1) kg. In this cohort, 14 patients underwent re-reconstruction of RVOT, including 12 patients with pulmonary regurgitation at 6.3 to 31.0 (median 13.8) years after tetralogy of Fallot (TOF) repair, and 2 patients with failed bovine jugular vein conduit (BJVC). Seven patients underwent Ross operations. Among them, 3 were for aortic valve stenosis, 2 were for aortic regurgitation, and 2 were for both stenosis and regurgitation. The ePTFE valved conduits were standard hand-sewn during the surgery. The 3 leaflets were equal in size with arc-shaped lower edge of the valve sinus. The free edge of the valve leaflets was straight with the length of about 1 mm longer than the diameter. The height of the valve sinus was 4/5 of the diameter. The junction of the valve leaflet was 3/4 of the height of the sinus. The designed leaflets were then continuous non-penetrating sutured into the inner surface of Gore-Tex vessel to make a valved conduit. Valved conduits with diameter of 18, 20, and 22 mm were used in 2, 9, and 10 cases, respectively. The surgical results, postoperative recovery time, and serious complications were summarized, and the changes of postoperative cardiac function status and hemodynamic status of the conduits were investigated.@*RESULTS@#During the implantation of ePTFE valved conduit for RVOT reconstruction, 2 patients underwent mechanical mitral valve replacement with Ross operation, 2 patients with pulmonary regurgitation with repaired TOF underwent left and right pulmonary artery angioplasty, and 1 patient with failed BJVC underwent tricuspid valvuloplasty. The cardiopulmonary bypassing time for patients underwent re-reconstruction of RVOT was (130.9±16.9) min, with aorta clamping for 1 patient to repair the residual defect of the ventricular septum. The cardiopulmonary bypassing and aorta clamping time for Ross operation were (242.7±20.6) min and (145.6±10.5) min, respectively. The duration of postoperative ventilator assistance, intensive care unit stay, and hospital stay were 3.5 h to 7.7 d (median 17.1 h),11.2 h to 29.5 d (median 1.9 d), and 6.0 to 56.0 (median 13.0) d, respectively. All patients survived after discharge from hospital. The follow-up rate after discharge was 100% with median time at 15.0 (13.0 to 39.0) months. No death happened during the follow-up. One patient underwent stent implantation due to right coronary stenosis 2 months after Ross operation. One patient underwent balloon dilation due to right pulmonary artery ostium stenosis 1 year after re-reconstruction of RVOT. The cardiac function of all patients recovered to NYHA class I 6 months after operation. The peak pressure gradient across the valve measured by transthoracic echocardiography before discharge was (9.4±2.6) mmHg (1 mmHg=0.133 kPa), and (18.3±6.1) mmHg at the last follow-up. There was no significant increase in the gradient during the follow-up (P=0.134). No patient suffered from mild or more pulmonary regurgitation.@*CONCLUSIONS@#Hand-sewn ePTFE valved conduit is feasible for RVOT reconstruction. It is a promising material for RVOT reconstruction which can effectively meet clinical need. In our experience, the ePTFE valved conduit is simple to manufacture with satisfactory early outcomes.In the application of ePTFE valved conduit, attention should be paid to implantation indications and postoperative anticoagulation management, especially to the preparation details of the valved conduit, to obtain better function and durability of the conduit after implantation.

Implante percutáneo de válvula pulmonar: a propósito de dos casos colombianos / Percutaneous pulmonary valve implant: Two Colombian case reports

Resumen Los pacientes con cardiopatías congénitas que afectan la continuidad del ventrículo derecho con la arteria pulmonar deben someterse con frecuencia a intervenciones debido a la limitada vida útil de los conductos quirúrgicos, lo que lleva al desarrollo de disfunción ventricular derecha por cambios en la geometría ventricular y predisposición a arritmias letales, con el consiguiente riesgo de reintervenciones. El implante valvular percutáneo pulmonar es una nueva alternativa terapéutica, menos invasiva en comparación con la quirúrgica, para pacientes seleccionados. Se realiza una revisión de las publicaciones médicas actuales disponibles y se describe la experiencia inicial del implante valvular pulmonar percutáneo en un centro colombiano de alta complejidad para el tratamiento de enfermedades cardiovasculares, en dos pacientes con disfunción del homoinjerto aórtico en posición pulmonar con doble lesión valvular, en los cuales el implante valvular pulmonar percutáneo fue una conducta exitosa. Se eligió a pacientes con cardiopatías congénitas, conductos quirúrgicos disfuncionales con estenosis o insuficiencia pulmonar significativa, y disfunción y dilatación ventricular derechas. Se empleó la técnica regular para el implante de la válvula pulmonar Melody, sin documentarse complicaciones durante el procedimiento ni al año de seguimiento. El implante percutáneo de la válvula pulmonar es un gran avance en el tratamiento de pacientes con cardiopatías congénitas, con resultados favorables a corto y mediano plazos, lo cual hace posible la restauración de la función ventricular con riesgo mínimo, frente al reemplazo quirúrgico en pacientes seleccionados.

Abstract Patients with congenital heart disease that involves reconstruction of the right ventricular outflow tract must frequently undergo interventions derived from the limited useful life of the surgical canals, which leads to the development of right ventricular dysfunction due to changes in the ventricular geometry and predisposition to lethal arrhythmias, with the consequent risk of reinterventions. The percutaneous pulmonary valvular implant is a new therapeutic alternative, less invasive, compared to surgery, for selected patients. A review of the available literature is made and the initial experience of percutaneous pulmonary valve implantation in a Colombian center of high complexity for the treatment of cardiovascular diseases is described, in two patients with aortic homograft dysfunction in a pulmonary position with double valvular lesion, in which the percutaneous pulmonary valve implant was a successful strategy. Patients with congenital heart disease were chosen, with dysfunctional surgical conduits with stenosis or significant pulmonary insufficiency, with dysfunction and right ventricular dilatation. The standard technique for the implantation of the Melody pulmonary valve was used, without complications during the procedure or one year of follow-up. Percutaneous implantation of the pulmonary valve is a great advance in the management of patients with congenital heart diseases, with favorable results in the short and medium term, allowing the restoration of ventricular function with minimal risk, compared to surgical replacement in selected patients.

Emprego e avaliação em médio prazo da cúspide de homoenxerto decelularizado na correção da tetralogia de Fallot / The use and midium-term evaluation of decellularized allograft cusp in the surgical treatment of the tetralogy of Fallot

OBJETIVO: Descrever a técnica de preparo e a evolução ecocardiográfica das cúspides de homoenxerto decelularizado utilizadas em pacientes com tetralogia de Fallot. MÉTODOS: No período de março de 2005 a agosto de 2007, 15 pacientes foram submetidos ao implante deste tipo de enxerto e foram acompanhados clinicamente e com ecocardiograma para avaliar o resultado morfofuncional dos enxertos. RESULTADOS: O acompanhamento médio foi de 12,7 meses (1-25 meses). A análise ecocardiográfica em médio prazo revelou: insuficiência pulmonar leve em nove (60 por cento) pacientes, moderada em três (20 por cento) e importante em três (20 por cento); a função sistólica do ventrículo direito esteve preservada em 13 (86,7 por cento) pacientes e com disfunção leve em dois (13,3 por cento); 11 (73,4 por cento) pacientes não apresentaram gradientes na via de saída do ventrículo direito (VD), e em quatro (26,6 por cento) pacientes evidenciou-se a presença de estenose leve; a mobilidade da cúspide foi normal em todos os pacientes; não houve espessamento maior de 1,5mm nas cúspides analisadas; não se detectou nenhuma calcificação nas cúspides. Catorze (93,3 por cento) pacientes apresentaram Z score entre -1 e 0,7 e um (6,7 por cento) paciente apresentou anel pulmonar com Z score de + 2,5. CONCLUSÃO: O retalho de homoenxerto decelularizado parece ser uma boa opção para a ampliação da via de saída do VD nos pacientes submetidos à correção total da tetralogia de Fallot em médio prazo.

OBJECTIVE: To describe the technique of implantation and to show the echocardiographic follow-up of the decellularized cusps allografts used in patients with tetralogy of Fallot. METHODS: Fifteen patients underwent this implantation between March 2005 and August 2007 and they were clinically followed-up. An echocardiogram was performed to evaluate the morphofunctional result of the allografts. RESULTS: The mean follow-up was 12.7 months (1-25 months). The echocardiography results showed that pulmonary insufficiency was mild in nine (60 percent) patients, moderate in three (20 percent) patients, and severe in three (20 percent) patients. The results also showed that the systolic right ventricle function was normal in 13 (86.7 percent) and that there was mild dysfunction in two (13.3 percent). Eleven (73.4 percent) patients did not present any gradient in the right ventricular outflow tract and four (26.6 percent) presented mild stenosis. The mobility of the cusps were normal in all cases and there was no thickness larger than 1,5mm. There was no calcification; 14 patients (93,3 percent) presented Z score between -1 and 0,7 and one patient presented dilated pulmonary annulus with a Z score of + 2.5. CONCLUSION: In midium-term follow-up, the decellularized allograft seemed to be a good option for right ventricle outflow tract enlargement in patients underwent tetralogy of Fallot.

Anuloplastia de homoenxerto pulmonar criopreservado com anel de Delrin na atresia pulmonar com comunicação interventricular / Annuloplasty of cryopreserved pulmonary homograft with Delrin stent in pulmonary atresia with ventricular septal defect

Criança de seis anos portadora de atresia pulmonar com comunicação interventricular, submetida a correção total com um ano, empregando monoválvula de pericárdio bovino na reconstrução da via de saída do ventrículo direito. Evoluiu com importante regurgitação valvar pulmonar (RVP) e disfunção do ventrículo direito. Na reoperação foi implantado homoenxerto pulmonar criopreservado (HPC) com anuloplastia, utilizando anel de Delrin com o intuito de evitar distorção geométrica do conduto. Após dois anos, o ecocardiograma, semelhante ao pós-operatório imediato, demonstra RVP discreta e função ventricular direita normal, sugerindo que essa manobra pode ser utilizada como coadjuvante para otimizar o resultado do implante do HPC.

A six-year-old child was suffering from pulmonary atresia with ventricular septal defect after a total correction at 1 year of age using a bovine pericardial monocusp valve in the reconstruction of the right ventricle outflow tract. The infant evolved with significant pulmonary valve regurgitation (PVR) and right ventricle dysfunction. On reoperation, a cryopreserved pulmonary homograft (CPH) was implanted with annuloplasty utilizing a Delrin ring with the aim of avoiding geometric distortion of the vessel. After two years, an echocardiogram proved a similar state to the immediate postoperative period with slight pulmonary valve regurgitation and normal right ventricular function suggesting that this maneuver may be used as coadjuvant treatment to optimize the result of CPH implantation.

Agenesia de valva pulmonar. Avaliação clínico-cirúrgica de 32 pacientes / Absent Pulmonary Valve. Clinical and Surgical Evaluation of 32 Patients

PURPOSE--To study the surgical and clinical evolution of 32 cases with absent pulmonary valve to propose the ideal period of time for surgical correction. METHODS--Clinical and laboratorial analysis were performed in 32 infants, under 12 months of age, between 1980 an 1993, in an evolutive character. From the clinical viewpoint, hypoxic and/or congestive features were considered in previous and late periods related to surgical repair. Laboratorial studies as ECG (cavities overload), chest X-ray (cardiac size and pulmonary vascular markings) and echocardiogram (associated defects, pressure gradients and anatomical aspects of pulmonary arteries) were also analyzed. Cardiac catheterization was performed in 15 patients. RESULTS--Early cyanosis in 84 of cases and "to and for "murmur in 90 of them facilitate clinical diagnosis in whom tetralogy of Fallot was associated in 30 patients. Refractory respiratory and cardiac insufficiency were responsible for operative indication in 12 patients, half of them, operated on under 12 months of age, died. Survival patients were repaired between two to 11 years old. Four deaths occurred early in life, before any surgical consideration and the 16 remaining patients will electively be considered for an opportune repair. CONCLUSION--Conservative clinical treatment is indicated, waiting for a more rigid bronchial wall can support the pressure of the dilated pulmonary arteries. This way, surgical repair is postponed for at least two years of age.

Reconstituiçäo da valva pulmonar e via de saída do ventrículo direito, com prótese bivalvular e prótese tubular valvada de tronco pulmonar de porco estudo experimental e aplicaçäo clínica / Pulmonary valve and outlet right ventricle reconstruction with bivalvular prosthesis and valved tubular prosthesis of the pig pulmonary trunk: experimental study and clinical application

A obstruçao da via de saída do ventrículo direito (VSVD) tem gerado muita polêmica em torno da técnica da sua correçao cirúrgica, sendo a reconstituiçao ainda motivo de controvérsias. Com essa finalidade, foram desenvolvidas duas próteses a partir do tronco pulmonar (TP) de porco: 1) a prótese bivalvular: poderia ser usada na correçao da tétrade de Fallot associada a hipoplasia do anel pulmonar: 2) a prótese tubular valvada, possuindo a própria valva pulmonar: poderia ser empregada na correçao de malformaçoes com descontínuidade entre o VD e TP. Estes dois tipos de próteses foram testados em modelo experimental. Seis ovelhas foram submetidas a implante de prótese bivalvular, com o auxílio da circulaçao extracorpórea (CEC), após ampla ressecçao do infundíbulo pulmonar, incluindo duas válvulas da valva pulmonar, procurando-se, com isto, imitar a reconstituiçao empregada no Fallot. O implante da protese tubular valvada foi realizado em 12 ovelhas, sem o auxílio da CEC, mediante pinçamento tangencial do infundíbulo e TP, permitindo o desvio do fluxo sangüíneo através do conduto, após ligadura do TP. A prótese bivalvular implantada foi avaliada mediante parâmetros hemodinâmicos e ecocardiográficos na fase intra-operatória, conferindo desempenho satisfatório (insuficiência pulmonar discreta ou ausente e gradientes VD-TP menores de 10 mmHg). A seguir, os animais foram sacrificados. O desempenho da prótese tubular valvada foi avaliada na fase intra-operatória com medidas hemodinâmicas, mostrando gradientes acima de 1O mmHg em apenas 3 casos. Sete ovelhas tiveram controle ecocardiográfico com 99 a 135 dias de evoluçao, registrando gradientes de 9,85 mmHg a 49 mmHg (média 19,7). Quatro casos foram submetidos a estudo hemodinâmico no 6( mês de evoluçao, registrando discreto aumento do gradiente (média 22,3); a seguir os animais foram sacrificados e encaminhados para estudo anatomopatológico. A aplicaçao clínica da prótese bivalvular foi realizada em 3 pacientes portadores de t.de Fallot associada a hipoplasia do anel pulmonar (2 casos) e agenesia da valva pulmonar (1 caso), com idades de 16, 2 e 7 anos. Após evoluçao de 3 a 10 meses, os gradientes variaram entre 10 mmHg e 20 mmHg e discreta insuficiência pulmonar valvar ao estudo ecodopplercardiográfico...

Right ventricular outflow tract reconstruction with the revuelta monocusp patch

El tratamiento de las cardiopatías congénitas con obstrucción del tracto de salida del ventrículo derecho requiere ensanchamiento del infundibulo pulmonar, el anillo valvular y la arteria pulmonar con un parche. Como se ha demostrado que la insuficiencia pulmonar no es deseable, se diseñó un parche con una válvula monocúspide para el tratamiento de estas cardiopatías. Este trabajo resume el curso de un paciente con una Pentalogía de Fallot, tratado con esta prótesis