Monocusp valve in right ventricular outflow tract

Sixty patients aged 5 days-10.3 years (mean 2.9 years) received monocusp valve implants in the right ventricular outflow tract in corrective surgery for congenital heart disease. The free edge of the monocusp valve was attached to the posterior wall of the new pulmonary tract to cover the entire root of the pulmonary tract when the monocusp valve closed. Follow-up was 3.8 (0-11.5) years. Early mortality was 8.3% (5/60) and late mortality 3.6% (2/55). Monocusp valve regurgitation developed in all patients. Moderate or severe valve failure was found in 30 patients at median 1.4, mean 2.2 (0.2-6.8) years postoperatively. Repeat surgery was performed in seven cases because of monocusp failure. It is emphasized that monocusps potentially give short-term reduction of pulmonary regurgitation when used for right ventricular outflow tract reconstruction. Only long-term follow-up can disclose whether all patients with a monocusp valve will require repeat surgery.     

Endovascular stent implantation for the management of postoperative right ventricular outflow tract obstruction: clinical efficacy.

OBJECTIVE: Extracardiac conduits between the right ventricle and pulmonary arteries commit patients to multiple reoperations. We reviewed our experience with stent implantation in obstructed conduits. METHODS: Between 1990 and 1997, stents were implanted across 43 conduits. The median age at procedure was 6 years (0.5-17 years), and the median interval between conduit insertion and stent implantation was 2.4 years (0.3-14 years). RESULTS: Mean systolic right ventricular pressures and gradients, respectively, decreased from 71 +/- 18 mm Hg and 48 +/- 19 mm Hg before to 48 +/- 15 mm Hg and 19 +/- 13 mm Hg after stent placement. Mean percentage of predicted valve area for body surface area increased from 26% +/- 12% to 48% +/- 17% after stent placement. Fifteen patients underwent a second transcatheter intervention (dilation or additional stent), and 2 patients, a third, allowing further postponement of surgery in 8 patients. One sudden death occurred 2.8 years after stent placement. Surgical conduit replacement has occurred in 20 patients. Body growth was maintained during follow-up. Freedom from surgical reintervention was 86% at 1 year, 72% at 2 years, and 47% at 4 years. Higher right ventricular pressure and gradient before and after stent placement and lower percentage of predicted valve area for body surface area after stent placement were associated with shorter palliation. CONCLUSION: Endovascular stent placement across obstructed conduits is a safe and effective palliation that allows for normal body growth.     

PTFE monocusp valve reconstruction of the right ventricular outflow tract

BACKGROUND: Transannular patching of right ventricular outflow tract obstructive (RVOTO) defects results in pulmonary insufficiency (PI). Biologic monocusp valves (MO) can prevent acute PI but are prone to early degeneration and progressive regurgitation. Polytetrafluoroethylene (PTFE, 0.1 mm) MO leaflets demonstrated favorable characteristics in animal studies, and the technique was applied to a variety of RVOTO anomalies. METHODS: From June 1990 through June 1999, 158 patients underwent either PTFE MO RVOT reconstruction (n = 115 patients; 120 implants) or nonvalved transannular repair (TA) repairs (n = 43 patients; 5 subsequent MO implants) at our institution. Standard MO construction techniques and TA repairs were utilized. Intraoperative, postoperative, and echocardiographic data with a mean interval of 2.6 years (range 6 months to 8 years) were used in retrospective fashion to compare clinical outcomes. In addition, PTFE monocusp valves beyond 6 months postimplant underwent echocardiographic analysis of MO function and durability. RESULTS: There were 4 early (MO-3, TA-1) and no late deaths. Overall, perioperative complications were not significantly different between MO and TA groups, nor were total hospitalization days (9.1 versus 10.7, p = 0.24). However, a significant difference in intensive care unit (ICU) utilization (3.6 versus 5.8 days, p = 0.03) favored MO patients. Patients with tetralogy of Fallot (TOF) and ventricular septal defect/pulmonary atresia (VSD/PA) undergoing the MO implant demonstrated a trend toward improved survival (p = 0.08) when compared to TA repairs. Intraoperative PI was graded mild in the MO group and moderate-severe in the TA group (p = 0.003). Progressive MO regurgitation occurred (mild-moderate) but remained significantly less than the transannular patch repairs (p < 0.05). CONCLUSIONS: Utilization of a PTFE MO valve prevents short-term and significantly reduces midterm PI. It is inexpensive, easy to construct, and demonstrates no evidence of stenosis, calcification, or embolization. Despite longer cardiopulmonary bypass and ischemic times, it reduces ICU stay and, in both TOF and VSD/PA patients, decreases operative morbidity and mortality.     

Autogenous pericardial valve conduit for right ventricular outflow tract reconstruction

Conduit failure is a common late complication of use of allogra0t conduits. Pericardial membrane valve conduits were used as an alternative to homografts for reconstruction of the right ventricular outflow tract (RVOT). A novel and expeditious technique of conduit reconstruction using autogenous and vascularized pericardium is described. The advantage of this technique is the ease of its construction and potential for growth of the conduit since intact and vascularized pericardium is used for reconstruction.     

Homologous monocuspid valve patch in right ventricular outflow tract reconstruction

BACKGROUND: In the surgical repair of tetralogy of Fallot or pulmonary atresia, pulmonary regurgitation may be detrimental in the postoperative period. We have used homograft monocuspid valve patch to prevent pulmonary insufficiency. METHODS: From September 1996 to December 1998, twenty-five patients, 4 months to 8 years of age (median 10.1 months) had homograft monocuspid valve in the procedure of right ventricular outflow tract reconstruction. The function of the monocuspid valve was assessed by echocardiogram and graded as trivial to mild, mild to moderate, moderate, and severe. We evaluated the degree of pulmonary insufficiency before discharge, at 3-6 months, and at 12 months after the operation. RESULTS: There was one hospital death due to fulminate adeno viral pneumonia. On echocardiogram, 21 patients (88%, 21/24) had no significant pulmonary insufficiency. Only one patient (4.5%) showed a moderate degree of pulmonary insufficiency. At 3-6 months, seventeen of twenty-one (81%) patients had no significant pulmonary insufficiency. There were fourteen patients who had follow-up over 1 year, and no patients showed newly developed significant pulmonary insufficiency. CONCLUSIONS: We concluded that the homograft monocuspid valve patch for right ventricular outflow tract reconstruction has provided excellent early results for the prevention of pulmonary insufficiency. However these effects are limited in duration and further close follow-up should be needed.     

Homograft valve insertion for pulmonary regurgitation late after valveless repair of right ventricular outflow tract obstruction.

OBJECTIVE: Pulmonary regurgitation after valveless repair of right ventricular outflow tract obstruction (RVOTO) results in progressive right ventricular (RV) dilatation and dysfunction in an increasing number of patients. Since 1989, we have exclusively used cryopreserved homografts to restore pulmonary valve competence in these patients. Our 9-year-experience with pulmonary valve insertion (PVI) in such cases has been reviewed to evaluate the indications for this procedure and its benefits. METHODS: From 1989 to 1998, 49 patients (original diagnosis: tetralogy of Fallot in 42 patients and pulmonary stenosis in seven) aged from 3 to 42 years (mean 18 +/- 9 years) underwent PVI with homografts late (mean 13 +/- 7 years) after valveless repair of RVOTO (transannular patch, n = 38; pulmonary valvulotomy therefore tau chi infundibular patch, n = 11). Preoperatively, all patients had severe pulmonary regurgitation, cardiomegaly, significant to severe RV dilatation and dysfunction, fatigue, reduced exercise tolerance, and were in NYHA class II (n = 43) or III (n = 6). Ten patients had ventricular arrhythmia. RESULTS: There was one early death, due to air embolism, and one late death, due to ventricular arrhythmia. All survivors but one, who subsequently underwent heart transplant, had symptomatic improvement after homograft insertion. The mean RV end-diastolic diameter decreased from 38 +/- 9 to 26 +/- 8 mm (P < 0.01), and cardiothoracic ratio decreased from 0.62 +/- 0.07 to 0.54 +/- 0.04 (P < 0.01). Good late homograft function was the rule, with all the survivors being free of reoperation for valve failure. At a mean follow-up of 42 +/- 28 months, 41 patients (87% of the survivors) were in New York Heart Association (NYHA) class I and six in class II. Within this group three patients are still in treatment for RV failure and five for ventricular arrhythmias. In these patients, the average interval between RVOTO repair and PVI was significantly longer than in the others (18 +/- 7 vs. 12 +/- 6 years, P < 0.01). CONCLUSION: Homograft PVI is safe and provides clinical improvement with a significant reduction in RV volume overload and excellent mid-term results in most patients with severe PR late after RVOTO repair. This procedure should be undertaken early in symptomatic patients, before severe RV failure and ventricular arrhythmias ensue.     

Polytetrafluoroethylene monocusp valve technique for right ventricular outflow tract reconstruction

Nonvalve transannular patch repair of right ventricular outflow tract obstructive (RVOTO) defects results in pulmonary insufficiency, which can contribute to early postoperative right ventricular dysfunction. In both animal and clinical studies, monocusp valves provide perioperative RVOT competence and improved right ventricular functional characteristics. In these reports, monocusp leaflet construction with 0.1-mm polytetrafluoroethylene (PTFE) appeared equal, or superior, to biologic monocusp valves. Construction of the polytetrafluoroethylene monocusp valve is an inexpensive and straightforward way to create a competent RVOT in a variety of RVOTO anomalies. Based on our clinical experience, it effectively prevents short-term and significantly reduces midterm pulmonary insufficiency without evidence of stenosis.     

One hundred pulmonary valve replacements in children after relief of right ventricular outflow tract obstruction

Background. Surgical repair of obstructive lesions of the right ventricular outflow tract (RVOT) in children commonly creates pulmonary valve incompetence that may eventually require pulmonary valve replacement (PVR). We reviewed our experience with PVR late after RVOT reconstruction.

Methods. We performed 100 PVRs in 93 children 1.1 months to 22.4 years (median 8) after RVOT reconstruction. Children with right ventricular to pulmonary artery conduits and primary PVRs were excluded. Age at PVR was 4.5 months to 27.9 years (median 9.5 years). Initial diagnosis was tetralogy of Fallot and variants, 62; critical pulmonary stenosis, 15; pulmonary atresia with intact ventricular septum, 7; and others, 9. Eleven patients had a redo PVR. A total of 62 PVRs were homografts; 38 were porcine valves.

Results. There was one early death. On follow-up of 5 months to 12.4 years (mean 4.9 years) there were no late deaths although 1 child underwent cardiac transplantation. Actuarial freedom from redo PVR at 8 years was 100% for porcine valves but 70% for homograft valves (p = 0.17). For children younger than 3 years at PVR, freedom from reoperation was 76% at 1 year and 39% at 8 years compared with freedom from redo PVR at 8 years of 100% for children older than 3 years. On latest echocardiogram 97% of porcine valves had mild or no pulmonary regurgitation compared with 72% of homograft valves.

Conclusions. PVR after RVOT reconstruction can be performed with low risk. Porcine valves may be superior to homograft valves although this advantage may be due to older age at time of PVR.     

Myxoma of right ventricular outflow tract with pulmonary artery obstruction

Myxomas in the ventricles are uncommon. We report one such case where the myxoma, arising from the right ventricle, was obstructing the right ventricular outflow tract and the patient presented with chest pain and severe dyspnea. The patient was operated upon urgently and the tumor was successfully removed after opening right ventricular outflow tract and pulmonary artery under cardiopulmonary bypass.     

Recurrent pulmonary intimal sarcoma involving the right ventricular outflow tract

Intimal sarcoma of the pulmonary artery is commonly misdiagnosed as chronic pulmonary embolism. Rarely, it can involve the right ventricular outflow tract and the pulmonary valve. We report a patient who was treated surgically for an intimal sarcoma of the pulmonary artery involving the right ventricular outflow tract and the pulmonary valve. The sarcoma recurred in about 8 weeks. It responded favorably to chemoradiation therapy and shows some signs of regression.     

Modified technique for heterotopic implantation of a right ventricular outflow tract conduit

This article describes a modified technique of side-to-side proximal connection of a conduit during heterotopic implantation in the right ventricular outflow tract. It results in a better geometry of the right ventricular outflow and avoids distortion of the valve annulus, especially when the newer generation of straight xenografts are used.     

肺动脉带瓣管道重建右心室流出道

目的 总结多中心临床试验采用佰仁思(BalMedic)肺动脉带瓣管道(以下简称带瓣管道)作为右心室流出道重建的临床试用情况和随访结果.方法 2007年1月至2010年10月,多中心的50例复杂先天性心脏病患儿(者)采用佰仁思肺动脉带瓣管道,男23例,女27例;年龄6个月～ 39岁,平均(4.90 ±7.63)岁;体质量4.50 ～ 65.00 kg,平均(16.20±13.69) kg.病种包括肺动脉闭锁伴室间隔缺损22例,纠正型大动脉错位伴肺动脉狭窄10例,永存动脉干7例,右心室双出口伴肺动脉狭窄4例,法洛四联症3例,完全性大动脉错位伴肺动脉狭窄2例,肺动脉狭窄和主动脉瓣狭窄伴关闭不全各1例.取相应大小的带瓣管道,重建右心室与肺动脉的连接.患儿(者)术后1个月、3～6个月和≥12个月,接受心脏超声复查,并填写随访表.结果 患儿(者)手术无死亡.术后随访≥12个月者中3例失访,1例死亡.肺动脉瓣环无狭窄率91.1％,中度反流率16.0％,右心室流出道无狭窄率95.6％,主肺动脉无狭窄率80.O％,左、右肺动脉无狭窄率73.3％.结论 多中心临床试验结果表明,佰仁思(BalMedic)肺动脉带瓣管道的有效性和安全性可满足临床治疗要求,中长期疗效有待进一步随访和观察.     

Aneurysm of pericardial right ventricular outflow tract patches.

Among 1,022 patients who underwent repair of tetralogy of Fallot, 252 received a pericardial patch of the right ventricular outflow tract; of these, 10 subsequently developed an aneurysm of the right ventricular outflow tract. Cardiac catheterization and angiography revealed moderate pulmonary insufficiency in all patients, a residual pressure gradient in the right ventricular outflow tract in 7, and a residual ventricular septal defect in 2 patients. Reoperation was indicated in 8 patients because of progressive distention of the aneurysm, residual infundibular or pulmonary artery stenosis, and recurrent ventricular septal defect. Reconstruction of the right ventricular outflow tract was accomplished by resection of the aneurysm and insertion of a woven Dacron patch in 5 patients, primary suture of the pulmonary artery in 2, and implantation of a woven Dacron conduit containing a Björk-Shiley cardiac valve prosthesis in 1 patient. There were no early or late deaths. When reconstruction of the right ventricular outflow tract is necessary, we recommend a woven Dacron patch because pericardium may form an aneurysm.     

Hemangioma of the right ventricular outflow tract

Obstruction of the right ventricular outflow tract by a primary cardiac tumor is rare. Six cases of right ventricular outflow tract obstruction by a primary cardiac hemangioma have been reported; all but one were detected before the age of 25 years. In this report, we review the literature and describe what we believe to be only the second reported case of right ventricular outflow tract obstruction produced by a cardiac hemangioma that presented in late adulthood.     

Palliative reconstruction of right ventricular outflow tract in tetralogy with hypoplastic pulmonary arteries.

Twenty-five symptomatic patients with tetralogy of Fallot underwent palliative reconstruction of the right ventricular outflow tract without closure of the ventricular septal defect. Their ages ranged from 5 months to 20 years (mean age, 3.5 years). Eight patients had had 13 prior systemic-pulmonary arterial shunts. There were six hospital deaths (24%). Three patients needed a repeat right ventricular outflow reconstruction. There was one late death. The other patients manifested clinical improvement; hematocrit decreased from 0.54 to 0.43 (p less than 0.01) and arterial oxygen saturation increased from 63.0% to 83.2% (p less than 0.01). The size of the pulmonary artery, defined as the ratio of the sum of the diameter of the right and left pulmonary arteries to the diameter of the descending aorta, increased from 0.72 to 2.06 (p less than 0.01). Sixteen patients underwent a corrective operation 2.4 years after palliation. The results of palliative right ventricular outflow tract reconstruction suggest that it may be an optional strategy for the treatment of symptomatic patients who have tetralogy of Fallot with severely hypoplastic pulmonary arteries.