Early results of the extracardiac conduit Fontan operation

BACKGROUND: Among the modifications of the Fontan operation, the extracardiac approach may offer the greatest potential for optimizing early postoperative ventricular and pulmonary vascular function, insofar as it can be performed with short periods of normothermic partial cardiopulmonary bypass and without cardioplegic arrest in most cases. In this study, we reviewed our experience with the extracardiac conduit Fontan operation, with a focus on early postoperative outcomes. METHODS AND RESULTS: Between July 1992 and April 1997, 51 patients (median age 4.9 years) underwent an extracardiac conduit Fontan operation. Median cardiopulmonary bypass time was 92 minutes and has decreased significantly over the course of our experience. Intracardiac procedures were performed in only 5 patients (10%), and the aorta was crossclamped in only 11 (22%). Intraoperative fenestration was performed in 24 patients (47%). There were no early deaths. Fontan failure occurred in 1 patient who was a poor candidate for the Fontan procedure. Transient supraventricular tachyarrhythmias occurred in 5 patients (10%). Median duration of chest tube drainage was 8 days. Factors significantly associated with prolonged resource use (mechanical ventilation, inotropic support, intensive care unit stay, and hospital stay) included longer bypass time and higher Fontan pressure. At a median follow-up of 1.9 years, there was 1 death from bleeding at reoperation. CONCLUSIONS: The extracardiac conduit Fontan procedure can be performed with minimal mortality and morbidity. Improved results may be related to advantages of the extracardiac approach and improved preservation of ventricular and pulmonary vascular function.     

体外循环心脏不停跳下心外管道Fontan手术

目的评估体外循环心脏不停跳下心外管道Fontan手术的方法及其效果。方法本组42例中,男性31例、女性11例,年龄3～19岁,其中心室双人口19例,三尖瓣闭锁10例,二尖瓣闭锁3例,其他复杂先天性心脏病10例。均在常温体外循环心脏不停跳下施行心外管道Fontan手术,其中8例加行开窗术;1例先做了双向腔肺动脉分流术,术后2年行心外管道Fontan手术。结果术后早期和晚期各死亡1例,分别死于急性肝功能衰竭和反复肺部感染,随访1．0～4．5年,40例心功能为Ⅰ级和Ⅱ级,动脉血氧饱合度92％～96％。结论体外循环心脏不停跳下心外管道Fontan手术的近、中期效果满意．可在单一心室修复中选用。     

Optimal conduit size for extracardiac Fontan operation

Background: Lack of conduit growth potential and thrombogenicity are the main drawbacks of the extracardiac Fontan operation (ECFO). Optimal size of the conduit according to the patients age and inferior vena cava diameter has not been established. Objectives: We set out to ascertain whether the optimal dimensions of the conduit could be determined before an ECFO. Methods: Actual and expected age-related inferior vena cava diameters were compared with the extracardiac conduit diameter in 20 patients after ECFO. In 50 other pediatric and adult patients, the distance between intrapericardial part of the inferior vena cava and the undersurface of the right pulmonary artery (IVC–RPA) was measured. Cases of conduit thrombosis were analyzed. Results: The actual diameter of the inferior vena cava was variable and has a weak correlation with anthropmetric data and expected diameter (R=0.07–0.23, P=0.32–0.76). The IVC–RPA distance correlated with height (R=0.87, P=0.0001), but was also variable. At the age of 2–4 years and body weight 12–15 kg IVC diameter and IVC–RPA distance are equal to 60–80% of adult values. Conduit thrombosis developed in two patients with unfavorable Fontan hemodynamics and oversized conduits. Conclusions: Considering the inferior vena cava size, ECFO may be performed at the age of 2–3 years and at a body weight 12–15 kg, when a hemodynamically optimal almost adult sized conduit can be implanted. Optimization of the conduit is necessary on the basis of the actual inferior vena cava diameter and IVC–RPA distance. Anticoagulation postoperatively should be considered to prevent conduit thrombosis in patients with suboptimal Fontan circulation     

Results of an extracardiac pericardial-flap lateral tunnel Fontan operation.

Objective: Extracardiac pericardial-flap lateral tunnel Fontan operation has the theoretical advantage of growth potentiality of the extracardiac tunnels. The mid-term results of this technique and morphologic change of the lateral tunnel were studied. Methods: Clinical data were reviewed in 42 patients who underwent extracardiac pericardial-flap lateral tunnel Fontan operation between November 1993 and December 2004. The age was 2.8+/-1.5 years and the body weight was 12.3+/-3.2kg. Extracardiac tunnel was constructed using the pedicled pericardium with the base undetached. By reviewing the follow-up cardiac angiograms (2.3+/-1.4 years postoperatively), ratios of diameter and cross-sectional area of the lateral tunnel to those of inferior vena cava were obtained. Results: There were 4 surgical mortalities (10%). Postoperative morbidity included prolonged pleural effusion in 5 patients and heart block in 1 patient. Follow-up was possible in 37 patients and the follow up duration was 3.8+/-2.2 years. There were two late deaths due to ventricular dysfunction and sudden death of unknown causes. Two patients required reoperation due to subaortic stenosis and stenosis between inferior vena cava and lateral tunnel. In one patient, bradyarrhythmia was observed but there was no thromboembolic complication. Follow-up anteroposterior and lateral diameter ratio were 1.1+/-0.5 and 1.2+/-0.5. The cross-sectional area ratio was 2.6+/-2.3. In 5 patients, fusiform dilatation of the lateral tunnel was observed, but in the remaining patients, the lateral tunnel preserved tubular morphology with good hemodynamics. Conclusions: Extracardiac pericardial-flap lateral tunnel Fontan operation is relatively simple and feasible even in patients with previous median sternotomies. The mid-term results were acceptable, and the lateral tunnel demonstrated a tendency to preserve its tubular shape. However in some patients, dilatation of the pericardial-flap tunnel was observed during follow up. Longer follow-up is required to determine the morphologic changes of the lateral tunnel and the value of this technique.     

Modified extracardiac Fontan with a fenestrated pericardial patch

Extracardiac Fontan is a preferred treatment strategy in many centers treating patients with single ventricle physiology, and many of these centers regularly include a fenestration between the extracardiac conduit and the common atrium. Spontaneous closure of the fenestration is a common complication of this technique and is independently associated with increased morbidity and mortality. Recently, we introduced a novel technique for fenestration of the extracardiac conduit wherein a pericardial patch is utilized at the fenestration point with excellent outcomes in the midterm fenestration patency rates, thus reducing the risk of acute post-Fontan complications.     

Revision of previous Fontan connections to total extracardiac cavopulmonary anastomosis: A multicenter experience

BACKGROUND: Conversion to total extracardiac cavopulmonary anastomosis is an option for managing patients with dysfunction of a prior Fontan connection. METHODS: Thirty-one patients (19.9 +/- 8.8 years) underwent revision of a previous Fontan connection to total extracardiac cavopulmonary anastomosis at four institutions. Complications of the previous Fontan connection included atrial tachyarrhythmias (n = 20), progressive heart failure (n = 17), Fontan pathway obstruction (n = 10), effusions (n = 10), pulmonary venous obstruction by an enlarged right atrium (n = 6), protein-losing enteropathy (n = 3), right atrial thrombus (n = 2), subaortic stenosis (n = 1), atrioventricular valve regurgitation (n = 3), and Fontan baffle leak (n = 5). Conversion to an extracardiac cavopulmonary connection was performed with a nonvalved conduit from the inferior vena cava to the right pulmonary artery, with additional procedures as necessary. RESULTS: There have been 3 deaths. Two patients died in the perioperative period of heart failure and massive effusions. The third patient died suddenly 8 months after the operation. All surviving patients were in New York Heart Association class I (n = 20) or II (n = 7), except for 1 patient who underwent heart transplantation. Early postoperative arrhythmias occurred in 10 patients: 4 required pacemakers, and medical therapy was sufficient in 6. In 15 patients, pre-revision arrhythmias were improved. Effusions resolved in all but 1 of the patients in whom they were present before revision. The condition of 2 patients with protein-losing enteropathy improved within 30 days. CONCLUSIONS: Conversion of a failing Fontan connection to extracardiac cavopulmonary connection can be achieved with low morbidity and mortality. Optimally, revision should be undertaken early in symptomatic patients before irreversible ventricular failure ensues.     

Catheter closure of autologous pericardial extracardiac Fontan fenestration

We describe two patients who required fenestration of an autologous pericardial extracardiac Fontan (APEF), short-medium term angiographic follow-up, and subsequent successful transcatheter closure of the fenestration.     

Modified extracardiac Fontan in a patient with separate hepatic venous drainage

We describe an alternative technique to the extracardiac Fontan procedure in a patient with a univentricular heart, in which the inferior caval vein and the hepatic vein drained separately into the common atrium and the intraatrial orifice of the hepatic vein was adjacent to the opening of the left lower pulmonary vein.     

Bovine valved xenograft (Contegra) conduit in the extracardiac Fontan procedure: the preliminary experience

OBJECTIVE: Constructing a competent valve using the xenograft valved conduit (Contegra) in the extracardiac Fontan connection may maintain better forward flow into the pulmonary circulation. The preliminary results and potential advantages of using the Contegra are discussed in this review. METHOD: A retrospective review of 18 patients who underwent the extracardiac Fontan connection using the Contegra conduit from June 2002 to September 2005. RESULTS: Median age at the time of operation was 4.5 year (range 2.5-34 years). In 15 patients (83%) a 4 mm fenestration was created. Overall operative mortality was 11 % (two patients); one patient died because of arrhythmia & sepsis, and the other one due to thrombosed Fontan connection. The ranges of intensive care unit stay, chest tube duration, and hospital stay were 1-18 days (median, 2 days), 4-38 days (median, 7 days), and 5-47 days (median, 12.5 days), respectively. Follow-up is available for 15 (94%) patients at a mean of 15.8 months (range 8-48 months) postoperatively. They were all asymptomatic and their room air oxygen saturation ranged between 88% and 100% (mean, 96.1%). There have been no further thromboembolic episodes during follow up. Echocardiograms demonstrated patent conduit in all patients with no hepatic vein reversal flow except to a minimal degree in five patients; however the valve competency was demonstrated radiologically. CONCLUSIONS: The Contegra xenograft is a potential alternative conduit for the extracardiac Fontan connections. These encouraging preliminary results may support better pulmonary forward flow.     

Comparison of lateral tunnel and extracardiac conduit Fontan procedure

The purpose of this study was to compare the outcomes of lateral tunnel (LT) and extracardiac conduit (ECC) Fontan procedures at a single institution. From April 1995 to December 2006, 165 Fontan procedures were performed (67 LT, 98 ECC). Pre-, intra- and postoperative variable values were compared between two different techniques. Operative mortality was 5 (3 LT, 2 ECC). Immediate postoperative transpulmonary gradient (LT 8.5+/-ECC 2.5 vs. 6.6+/-2.4 mmHg) and central venous pressure (LT 18.3+/-3.8 vs. ECC 15.6+/-2.4 mmHg) showed significant difference (P<0.001). The LT patients had a higher incidence of sinus node dysfunction in the postoperative period (22.4% vs. ECC 11.2%; P=0.05). Mean follow-up was 74.1+/-31.5 months in LT, and 31.7+/-28.1 months in ECC patients. There was one late death. Actuarial survival at 10 years is 92% for LT, and 89% for ECC patients (P=0.796). The LT and ECC, both, showed comparable early and mid-term outcomes in operative morbidity and mortality, postoperative hemodynamics, survival. Use of ECC for modified Fontan operation reduces the risk of sinus node dysfunction and shows better outcome of immediate postoperative hemodynamics.     

Comparison of somatic development and status of conduit after extracardiac Fontan operation in young and older children

Objective: We set out to examine whether the extracardiac Fontan operation (ECFO) in young children is beneficial for the early postoperative course and whether it has a negative impact on the mid-term hemodynamics and growth of the children due to absent growth potential of the prosthetic conduit. Therefore we compared our medium-term experience with ECFO in children under 4 years of age to that in older children regarding the incidence of postoperative complications, somatomotoric development and conduit status. Methods and results: Between 11/95 and 12/02 ECFO was performed in 30 children under 4 years of age and 21 older children aged 4–13 years. There were no deaths in children under 4 years of age and two older children died. No prolonged support (>72 h) of suprarenin was required in small children compared to 4 older children. In twenty-seven children, who underwent postoperative heart catheterization no pulmonary artery or systemic vein distortion occurred. One re-operation and one transcatheter intervention were performed because of the partial conduit stenosis. During the median follow-up of 4.8 years a manifestly accelerated postoperative weight gain was observed in children operated on under 4 years of age, compared to that in older children (up to the 50 vs. 10th percentile, P<0.05). Conclusions: The ECFO could be performed in young children with low morbidity and mortality rates. In the majority of patients, implanted prosthetic grafts maintain stable form without the development of stenosis. Accelerated somatic development, especially in small children, is to be observed after completion of the Fontan circulation.