同种带瓣管道应用的远期效果

目的　评价同种带瓣管道应用后的远期效果。方法　1988年1月至1997年12月的10年间应用同种带管道瓣治疗165例多种复杂先天性心脏病(先心病)，其中主动脉带瓣管道136例、肺动脉带瓣管道29例。病人年龄1.3～22.0岁，平均7.6岁。体重9.5～58.0kg，平均22.0kg。管道直径17～22mm，平均19mm。结果　术后早期（30d内）死亡40例，死亡率为24%。术后随访10个月～12.1年，平均(37.0±8.6)个月。病人术后5、10年生存率分别为94.6%、83.8%，带瓣管道完好率分别为83%、58%。结论　应用同种带瓣管道治疗复杂先心病，远期疗效比较满意。     

Long-term outcome of right ventricular outflow tract reconstruction with bicuspidalized homografts

Objective: Given the shortage of small-sized cryopreserved homografts for right ventricle (RV) to pulmonary artery (PA) reconstructions, more readily available larger-sized homografts can be used after size reduction by bicuspidalization. The aim of our study was to determine and compare function over time of standard and bicuspidalized homografts in infants younger than 12 months, including patients with a Ross or extended Ross procedure. Methods: All consecutives infants under the age of 1 year, who underwent a surgical procedure in which a homograft was placed in the RV-PA position between January 1994 and April 2009, were included. Prospectively collected data from serial, standardized echocardiography from all patients were extracted from the database, and hospital records were retrospectively reviewed. Results: A total of 40 infants had a valved homograft conduit placed in the RV-PA position. In 20 of those patients, a bicuspidalized homograft was used. Twelve patients underwent a Ross procedure, of whom seven had an additional Konno-type aortic annulus enlargement. Median follow-up was 146 months (interquartile range (IQR), 117–170; total patient years: 178) in the group with standard use of the homograft and 95 months (IQR, 11–104; total patient years: 78) in the group with bicuspidalized conduits. Freedom from re-intervention (re-operation or percutaneous) was not different in the standard and bicuspidalized groups for all and Ross or Konno–Ross procedures (Tarone-Ware, p = 0.65 and p = 0.47, respectively). Consecutive echocardiographic maximum velocities in the right ventricular outflow tract were similar in the standard and bicuspidalized groups. Conclusion: When proper sized cryopreserved homografts for placement in the RV-PA position in Ross, Konno–Ross, and other procedures in infants under the age of 1 year are not readily available, bicuspidalized homografts provide an acceptable alternative.     

Long-term results of right ventricular outflow reconstruction with valved conduit

Twenty-nine patients who underwent right ventricular outflow tract reconstruction using a valved conduit 37 times and survived surgery, were reviewed in this study. Hancock, Ionescu-Shiley, Carpentier-Edwards and Polystan was used for RVOTR. Freedom from reoperation rates of Hancock, Ionescu-Shiley and Carpentier-Edwardsat at five and ten years after surgery were 100%, 85.7%, 89.2% and 75%, 28.6%, 89.2%, respectively. The freedom from reoperation rates of Hancock and Carpentier-Edwards were significantly higher than that of Ionescu-Shiley. In conclusion, the freedom from reoperation rate at ten years was high for both Hancock and Carpentier-Edwards.     

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.     

Carpentier edwards porcine valved conduit for right ventricular outflow tract reconstruction

Abstract Background: The optimal conduit for right ventricular outflow tract (RVOT) reconstruction is uncertain, with varying degrees of longevity reported for pericardial, homograft, and xenograft valves utilized in this position. Methods: A retrospective review of children and adults with congenital heart disease who underwent RVOT reconstruction with the Carpentier Edwards? (CE) porcine valved conduit was conducted from 2001 to 2009 at the University of Rochester and SUNY Upstate Medical Centers. Clinical data were analyzed for each subject according to conduit size, and all of the Doppler derived transconduit gradients from postoperative echocardiograms were analyzed. Results: Two hundred and eighteen patients received a single CE conduit for RVOT reconstruction with conduit size ranging from 12 to 30 mm. Perioperative mortality was 1.8% (4/218). Follow‐up data were available for 95% of subjects with duration of follow‐up ranging from 1 to 9 years. The increase in transconduit gradient over time was inversely proportional to conduit size. For the entire series, freedom from reoperation was 70.3% at 8.2 years. Patients receiving 25 and 30 mm conduits demonstrated no gradient development over this period of follow‐up. Conclusions: In this series, the CE conduit showed excellent longevity at intermediate term follow‐up, with slower progression of conduit stenosis as measured by RVOT gradient change compared with previous reports. (J Card Surg 2011;26:643‐649)     

Long-term effect of polystan monocusp ventricular outflow patch after right ventricular outflow tract reconstruction

Forty-eight patients who underwent right ventricular outflow tract reconstruction with Monocusp Ventricular Outflow Patch (MVOP) fifty-five times and survived surgery, were reviewed in this study. Mean age at surgery was 6.4 years-old and mean follow-up interval was 75.2 months. There was no late death, however reoperation was performed 7 times. Freedom from reoperation rate was 97.2% and 80.7% after 5 and 10 years after surgery, respectively. The main cause for reoperation were right ventricular outflow obstruction RVOTO (5 cases). All of the RVOTO occurred at the distal end of the anastomosis. However, there was no RVOTO in patients who underwent RVOTR with MVOP during the past ten years. So, we considered the cause of RVOTO a technical problem. Pulmonary regurgitation was one to two degree early after surgery, and had worsened by almost two or three degrees more than 5 years after surgery. Moreover, five of six patients who underwent cardiac catheterization more than 10 years after surgery had three degrees of pulmonary regurgitation as well as a large CTR. In conclusion, according to long-term results, especially more than 10 years post operatively, pulmonary regurgitation was the most important problem.     

重建右心室流出道中BalMedic管道与同种异体带瓣管道比较

目的 比较国产牛颈静脉带瓣BalMedic管道与同种异体带瓣管道(Homograft)在右心室流出道重建中的临床效果.方法 2003年1月至2009年7月,使用Homograft管道重建右心室流出道患者10例,使用BalMedic管道重建右心室流出道患者14例.术后1年复查超声心动图,检测移植管道内径、远端吻合口压差、新建肺动脉瓣跨瓣压差、有无血栓形成或瘤样扩张及肺动脉瓣反流程度.结果 Homograft组9例治愈出院,1例因感染性心内膜炎引起多器官功能衰竭死亡,与管道明确相关;BalMedic管道组13例治愈出院,1例于术后第2天因心力衰竭死亡.两组肺动脉瓣及远端吻合口均未见明显狭窄(压差＜ 20 mm Hg)(1 mm Hg=0.133 kPa),且组间差异无统计学意义(P＞0.05).两组均无血栓形成,且未见瘤样扩张.Homograft组肺动脉瓣轻度反流2例,中度1例;BalMedic管道组轻度反流4例,无中、重度反流.结论 对于右心室流出道重建,两种管道可获相同治疗效果.鉴于BalMedic管道方便获取、易于保存及更加匹配等特点,将有更好的应用前景.     

Late results of right ventricular outflow tract reconstruction with a bicuspid expanded polytetrafluoroethylene valved conduit

Background and Aim to Read

We report the results of a bicuspid expanded polytetrafluoroethylene (ePTFE) valved conduit used for right ventricular outflow tract reconstruction (RVOTR).

Methods

Between November 2005 and February 2009, 12 conduits were used for RVOTR. The mean age and weight of patients were 43.5 ± 46.4 months and 13.4 ± 8.6 kg. The main diagnosis was tetralogy of Fallot with pulmonary atresia in eight patients. The most common conduit size was 18 mm. The mean follow‐up was 88.0 ± 35.9 months.

Results

There were no operative and late mortalities. At discharge, the mean peak systolic pressure gradient across the RVOT was 14.1 ± 11.3 mmHg. There was no conduit valve regurgitation in nine patients. At the latest echocardiography (mean follow‐up: 84.3 ± 35.5 months), the mean peak systolic pressure gradient across the RVOT was 59.7 ± 20.2 mmHg, and there was no conduit valve regurgitation in six patients. Freedom from conduit malfunction was 100% and 83.3%, at 1 and 8 years, respectively. Two conduits were explanted due to sternal compression and four from conduit malfunction. Freedom from explantation was 83.3% and 74.2% at 2 and 8 years, respectively.

Conclusions

ePTFE bicuspid valved conduit has good late function in terms of valve regurgitation, but the pressure gradient across the conduit increases with time, which is the main cause of conduit failure and explantation.     

In vitro evaluation of right ventricular outflow tract reconstruction with bicuspid valved polytetrafluoroethylene conduit

Conduits available for right ventricular outflow tract (RVOT) reconstruction eventually become stenotic and/or insufficient due to calcification. In order to reduce the incidence of reoperations we have developed and used a bicuspid valved polytetrafluoroethylene (PTFE) conduit for the RVOT reconstruction. The purpose of this study is to investigate the hemodynamic performance of the new design using a pediatric in vitro right heart mock loop. PTFE conduit has been used for the complete biventricular repair of 20 patients (age 1.7±6 years) with cyanotic congenital defects. To account for the large variability of conduit sizes, 14, 16, 22, and 24-mm conduit sizes were evaluated using an in vitro flow loop comprised of a pulsatile pump with cardiac output (CO) of 1.2-3.2L/min, bicuspid valved RVOT conduit, pulmonary artery, venous compartments, and the flow visualization setup. We recorded the diastolic valve leakage and pre- and post-conduit pressures in static and pulsatile settings. In vitro valve function and overall hemodynamic performance was evaluated using high-speed cameras and ultrasonic flow probes. Three-dimensional flow fields for different in vivo conduit curvatures and inflow regimes were calculated by computational fluid dynamics (CFD) analysis to further aid the conduit design process. The average pressure drop over the valved conduits was 0.8±1.7mm Hg for the CO range tested. Typical values for regurgitant fraction, peak-to-peak pressure gradient, and effective office area were 23±2.1%, 13±2.4mm Hg, and 1.56±0.2 cm(2) , respectively. High-speed videos captured the intact valve motion with asymmetrical valve opening during the systole. CFD simulations demonstrated the flow skewness toward the major curvature of the conduit based on the pulmonic curvature. In vitro evaluation of the bicuspid valved PTFE conduit coincides well with acceptable early clinical performance (mild insufficiency), with relatively low pressure drop, and intact valve motion independent from the conduit curvature, orientation or valve location, but at the expense of increased diastolic flow regurgitation. These findings benchmark the baseline performance of the bicuspid valved conduit and will be used for future designs to improve valve competency.     

Reoperative homograft right ventricular outflow tract reconstruction

BACKGROUND: Homografts are implanted in the right ventricular outflow tract (RVOT) of children, with the knowledge that reoperation might be required. We reviewed 14 years of homograft RVOT reconstruction to assess the feasibility of homograft replacement and to determine risk factors for homograft survival. METHODS: From February 1985 through March 1999, 223 children (age 5 days to 16.9 years) underwent primary RVOT reconstruction with an aortic or pulmonary homograft. Of these, 35 patients underwent homograft explant at the implanting hospital with insertion of a second homograft from 2 months to 13.3 years after the first implantation. The primary operation and reoperation patient groups were compared with regard to incidence of early death, late death, homograft-related intervention without explant, and homograft explant. RESULTS: Actuarial survival and event-free curves for initial and replacement homografts were not significantly different. Univariable analysis was performed for the following risk factors: weight (p < 0.0001), age (p < 0.003), homograft diameter (p < 0.0001), homograft type (p < 0.01), surgery date (not significant [NS]), gender (NS), Blood Group match (NS), and type of distal anastomosis (NS). Multivariable analysis of significant univariable risks revealed small homograft diameter to be a significant risk factor (p < 0.001) for replacement. CONCLUSIONS: The RVOT homografts eventually require replacement. Patient and homograft survival for replacement homografts is similar to primary homografts. Reoperative homograft RVOT reconstruction is possible, with reasonably low morbidity and mortality.     

Options for right ventricular outflow tract reconstruction

The popularity of the Ross operation has drawn attention to the need for a satisfactory replacement of the excised pulmonary valve and artery. Although living autogenous tissue is desirable, it has not been possible to manufacture a satisfactory living conduit, and pulmonary homografts have provided a satisfactory long-term solution. Now, with the increasing shortage of homografts, a number of alternative options have to be considered. The most useful and readily acceptable replacement is a porcine pulmonary xenograft, which is now commercially available. Other prospects for future consideration relate to the use of transgenic pig tissue and developing techniques of tissue engineering. In emergency conditions where a valve conduit is unavailable, a temporary solution is to use a simple tube of autogenous pericardium.     

Right ventricular outflow tract reconstruction with an allograft conduit

BACKGROUND: Allograft conduits are used for reconstruction of the right ventricular outflow tract in patients with congenital heart disease and in the pulmonary autograft procedure. A retrospective evaluation of our experience with the use of allograft conduits for reconstruction of the right ventricular outflow tract was conducted. METHODS: Between August 1986 and March 1999, 316 allografts (246 pulmonary, 70 aortic) were implanted in 297 patients for reconstruction of the right ventricular outflow tract. Main diagnostic groups were aortic valve pathology (n = 112, 35%), tetralogy of Fallot (n = 71, 22%), and pulmonary atresia with ventricular septal defect (n = 46, 14%). Kaplan-Meier analyses were done for survival, valve-related reoperation, and valve-related events. In addition, Cox regression analysis was used for evaluation of potential risk factors. RESULTS: Mean age at operation was 18 years (range, 7 days to 61 years). Mean follow-up was 4 years (range, 2 days to 12 years). Twelve patients (4%) died within 30 days after operation. Patient survival was 90% (95% confidence interval [CI], 86% to 94%) at 5 years and 88% (95% CI, 83% to 94%) at 8 years. Twenty-four reoperations were required for allograft dysfunction in 23 patients; 21 allografts were replaced. Freedom from valve-related reoperation was 91% (95% CI, 86% to 95) at 5 years and 87% (95% CI, 81% to 93%) at 8 years. Twenty-nine valve-related events were reported (2 deaths, 24 reoperations, 2 balloon dilatations, and 1 endocarditis). Freedom from valve-related events was 90% (95% CI, 85% to 94%) at 5 years after implantation, and 84% (95% CI, 77% to 91%) at 8 years. Risk factors for accelerated allograft failure were extra-anatomic position of the allograft (p = 0.03; hazard ratio, 9.7) and the use of an aortic allograft (p = 0.02; hazard ratio, 2.4). CONCLUSIONS: Right ventricular outflow tract reconstruction with an allograft conduit has good medium-term results, although progression of allograft degeneration is noted. Aortic allografts should preferably not be used for reconstruction of the right ventricular outflow tract.     

Expanded polytetrafluoroethylene-valved conduit with bulging sinuses for right ventricular outflow tract reconstruction in adults

Purpose  

Generally, right ventricular outflow tract reconstruction in adults is performed using homografts or xenograft. However, sufficient graft material is difficult to obtain and has the problems of calcification and structure destruction. We, therefore, evaluated using expanded polytetrafluoroethylene- (ePTFE)-valved conduits with bulging sinuses for right ventricular outflow tract reconstruction in adults.     

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.     

Right ventricular outflow tract reconstruction using Contegra valved conduit: natural history and conduit performance under pressure.

OBJECTIVE: To assess the performance of the bovine Contegra valved conduit used for right ventricular (RV) outflow tract reconstruction, particularly in relation to post-operative RV pressure. METHODS: Follow-up study of 64 consecutive right ventricular to pulmonary artery-conduit implants in 62 patients between January 2000 and April 2003. The majority of cases were forms of pulmonary atresia/VSD (n=24, 39%) or Fallot's tetralogy (n=13, 21%). Thirteen cases (21%) had aortic atresia, truncus arteriosus or discordant connections with pulmonary atresia/VSD. Twelve cases (19%) were conduit replacements. Echocardiography was performed for a median follow-up of 14 months (range 0-38 months). RESULTS: Median age at implantation was 13.8 months (range 0.1-244 months) and median weight was 8.9 kg (range 2.1-84.1 kg). Thirty-eight patients (59.4%) were <10 kg at the time of surgery. Early mortality was 6.4% (n=4). During follow-up there were four explantations (one for endocarditis and three for conduit dilatation) and 16 (28.6%) catheter interventions. Overall freedom from intervention at 1 and 3 years was 71+/-6% and 53+/-11%, respectively. Freedom from conduit-specific reintervention was 66+/-11% at the end of the study period. Reintervention was associated with small conduits (p=0.04), age <1 year (p=0.04) and with high RV/LV pressure ratio in the immediate post-operative period (p=0.0003). On multivariate analysis, the RV/LV pressure ratio was the strongest single factor predicting the overall reintervention (OR 5.45). Acquired distal conduit stenosis at suture line was the commonest indication for conduit-specific reintervention and was associated with the smaller conduits. The conduits explanted for dilatation showed neointimal proliferation, thrombosis, calcification and chronic inflammation. CONCLUSIONS: The Contegra conduit is widely applicable to RVOT reconstruction with satisfactory mid-term results. However, there is a significant incidence of conduit-related complications, particularly with the smaller conduits. Adverse performance was strongly associated with high RV/LV pressure ratio at completion of surgery. We would recommend cautious use of the conduits in patients with predicted high RV/LV pressure ratios, where careful monitoring of conduit performance is crucial. There is some element of unpredictability, which adds to the importance of close follow-up. Further studies are needed to explore the issues of thrombogenicity, degeneration, possible 'rejection', and the potential role of anti-platelet and anti-inflammatory modulation.