New onset arrhythmias after the extracardiac conduit Fontan operation compared with the intraatrial lateral tunnel procedure: early and midterm results

Background

Arrhythmias are one of the main causes of postoperative morbidity superseding Fontan operations. Comparative data on the incidence of sinus node dysfunction after the extracardiac Fontan operation (ECFO) and the intraatrial lateral tunnel Fontan operation (LTFO) are very limited and controversial. The aim of this study was to evaluate whether ECFO decreases the risk of postoperative arrhythmias compared with LTFO.

Methods

Seventy-four consecutive patients received either an LTFO (n = 29, 5 recordings in 1992 to 9 recordings in 1997) or an ECFO (n = 45, 11 recordings in 1995 to 5 recordings in 2001). The rhythm was documented preoperatively and postoperatively with standard electrocardiogram (ECG) recording and ECG monitoring. During follow-up all patients had 2-8 (median 3) standard ECG recordings per year. Additionally 45 patients (65%) had a Holter ECG at least once a year.

Results

Median follow-up post-ECFO was 4.4 years (1.6-7.2) and post-LTFO it was 7.9 years (5.4-11.1). There were 5 early deaths (3 LTFO, 2 ECFO) and 1 late death (LTFO) (total mortality 8%). Sinus rhythm persisted in 37 ECFO patients (86%) as compared with 13 LTFO patients (50%) (p < 0.001). The incidence of new onset supraventricular tachyarrhythmias (SVTs) post-ECFO compared with LTFO was lower: 5 patients (11%) versus 11 patients (38%) early postoperatively (p < 0.001) and none versus 7 patients (27%) during follow-up (p < 0.001), respectively. Early postoperatively 10 LTFO patients (34%) and another 3 patients during follow-up required permanent pacemaker implantation due to bradyarrhythmias, but none of the ECFO patients required this.

Conclusions

Our data suggest that ECFO decreases the incidence of postoperative new onset arrhythmias during early and midterm follow-up compared with LTFO.     

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     

Lateral tunnel versus extracardiac conduit Fontan procedure: a concurrent comparison

BACKGROUND: The aim of this study was to compare the outcomes of the lateral tunnel (LT) and extracardiac conduit (ECC) Fontan procedures at a single institution over the same time period. METHODS: From November 1995 through October 2002, 70 Fontan procedures were performed: 37 LT and 33 ECC. All were fenestrated; 96% were staged with a prior superior cavopulmonary connection. Compared with the ECC patients, the LT patients were younger (2.7 +/- 1.1 vs 3.9 +/- 2.5 years; p = 0.01), had a higher incidence of hypoplastic left heart syndrome (57% vs 21%; p < 0.01), and a longer aortic cross-clamp time (55 +/- 13 vs 26 +/- 15 min; p < 0.01). Weight, gender, preoperative cardiac catheterization values, and cardiopulmonary bypass time did not differ between the two groups. RESULTS: Operative mortality was 2.8%, 1 patient in each group (p = 1.0). Over the first 24 hours following operation the mean Fontan pressure, transpulmonary gradient, and common atrial pressure did not differ between LT and ECC patients. The median duration of mechanical ventilation (LT 12 vs ECC 18 hours), intensive care unit stay (LT 2 vs ECC 3 days), chest tube drainage (LT 10 vs ECC 8 days), and hospital stay (LT 11 vs ECC 12 days) did not differ. The ECC patients had a higher incidence of sinus node dysfunction both in the postoperative period (27% vs LT 8%; p = 0.09), and persisting at hospital discharge (10% vs LT 0%; p = 0.02). Mean follow-up was 3.6 +/- 1.6 years in LT, and 3.0 +/- 2.2 years in ECC patients (p = 0.2). There was one late death. Actuarial survival at 5 years is 97% for LT, and 91% for ECC patients (p = 0.4); 96% of patients are in NYHA class I, and 4% in class II, with no difference between groups. Sinus node dysfunction was seen during follow-up in 15% LT vs 28% ECC patients (p = 0.2). CONCLUSIONS: The LT and ECC approaches had comparable early and mid-term outcomes, including operative morbidity and mortality, postoperative hemodynamics, resource use, and mid-term survival and functional status. ECC patients had a higher incidence of sinus node dysfunction early after operation.     

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。     

A new method for reliable fenestration in extracardiac conduit Fontan operations

A fenestrated extracardiac conduit Fontan operation was performed with a new method in 5 patients by means of a pericardial tube anastomosed end to end with the inferior inlet of the right atrium.     

Temporary fenestration using venoatrial extracorporeal membrane oxygenation after the Fontan operation

A 28.7-month-old male child who had undergone a Norwood operation and bidirectional cavopulmonary shunt at the age of 5 days and 6.6 months, respectively, underwent the extracardiac conduit Fontan operation. After the operation, high-volume resuscitation was needed, which led to high central venous pressure (CVP) and low arterial oxygen saturation. Venoatrial extracorporeal membrane oxygenation (ECMO) was initiated between the superior vena cava and the right atrium with one third of the expected normal cardiac output. This low-flow venoatrial ECMO immediately terminated the vicious cycle caused by high venous pressure in the Fontan circulation. He was weaned from ECMO and discharged home.     

Venous cannulation for extracorporeal circulation after total cavopulmonary connection with extracardiac conduit

We report two cases of venous cannulation after a total cavopulmonary connection (TCPC) with extracardiac conduit. Venous cannulation was performed via side graft sutured to the extracardiac conduit in an end-to-side fashion. The first case was a 3-year-old girl, who suffered from an atypical inferior vena cava obstruction after TCPC. The obstruction region was distal to the anastomosis site of extracardiac conduit and inferior vena cava. She underwent a surgical release of obstruction under cardiopulmonary bypass without circulatory arrest. The second case was a 2-year-old girl, who needed an extracorporeal membrane oxygenation support after TCPC due to severe low cardiac output syndrome. She was decannulated successfully after thirty-nine-hour support.     

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.     

Total cavopulmonary connection with an extracardiac conduit: experience with 100 patients

BACKGROUND: In the Fontan procedures total cavopulmonary connection with an extracardiac conduit is a concern. The potential benefits of an extracardiac conduit may be the avoidance of postoperative supraventricular arrhythmias over the long-term, hemodynamic benefits due to laminar flow, possibility of completion without anoxic arrest, and applicability to anomalous systemic or pulmonary venous return, or both anomalous systemic and pulmonary venous return. We demonstrate early to midterm results of total cavopulmonary connection with an extracardiac conduit. METHODS: Between March 1994 and February 2000, a total of 100 patients underwent total cavopulmonary connection with an extracardiac conduit. In 27 patients, who underwent a single stage total cavopulmonary connection operation, 7 were done without palliation. Seventy-three patients had undergone a bidirectional Glenn shunt before completion of the total cavopulmonary connection. We used an expanded polytetrafluoroethylene tube graft as the extracardiac conduit. RESULTS: Cardiopulmonary bypass time was 133.2+/-55.2 minutes. Myocardial ischemic time was 38.5+/-23.2 minutes in 40 patients who needed cardioplegic cardiac arrest for intracardiac procedures. Intraoperative fenestration was done in only 1 patient. There were no operative deaths. During follow-up of 37.3 months, there were 5 late deaths. When compared with the patients treated by the lateral tunnel technique in our institute, there was no significant difference in actuarial survival rate, but the event free rate of the extracardiac conduit group was significantly superior to the lateral tunnel group. CONCLUSIONS: Total cavopulmonary connection with the extracardiac conduit produced good results in short to midterm follow-up.     

Comparison of extracardiac Fontan techniques: pedicled pericardial tunnel versus conduit reconstruction

OBJECTIVE: This study was designed to determine whether either of 2 alternative methods of extracardiac Fontan reconstruction provides superior results. METHODS: We reviewed 58 consecutive Fontan procedures performed between 1995 and 2001 with a pedicled pericardial tunnel (group P, n = 21) or an extracardiac conduit of polytetrafluoroethylene or allograft aorta (group C, n = 37). Operations were performed with cardiopulmonary bypass at 32 degrees C; an aortic crossclamp was applied in only 6 patients. All group P patients and 33 (89%) group C patients received fenestrations. RESULTS: The groups were similar in terms of age, weight, anatomy, and preoperative hemodynamics. There were 3 hospital deaths (5%; 70% confidence limit, 2%-30%), all in group C. Median durations of mechanical ventilation (group P, 1 day; group C, 1 day), intensive care unit stay (group P, 3 days; group C, 3 days), chest tube drainage (group P, 8 days; group C, 7 days), and hospitalization (group P, 10 days; group C, 9 days) were not significantly different. There were no late deaths. All patients received warfarin sodium, and there were no late strokes. Before the Fontan procedure, 1 patient in group P and 3 patients in group C required pacemaker implants. Of the 51 surviving patients in sinus rhythm before the Fontan procedure, only 1 patient in group C subsequently required a pacemaker. CONCLUSIONS: Extracardiac Fontan procedures with either a pericardial baffle or conduit are associated with low operative mortality and low risks of arrhythmia and late thromboembolic complication.