Early and medium-term results after modified Fontan operation in adults

Single ventricle palliation is rarely performed in adults and the results are less optimal than in children. In this article we analyze our experience with the modified Fontan operation in this age group.

Data of 15 consecutive patients with single ventricle with a mean age of 26 (range 16-38) years, who underwent Fontan operation between 3/92 and 1/2000 were retrospectively analyzed. Five patients had previously had an aortopulmonary shunt in childhood and two patients had previously received a bi-directional cavopulmonary shunt as adults. Eleven patients were preoperatively in NYHA class III and four in class II. The main factors for the selection of the patients before surgery were well-developed pulmonary arteries with lower lobe index 120+30 mm/m(2), pulmonary artery pressure <18 mmHg, good cardiac function and enddiastolic systemic ventricular pressure <12 mmHg. The lateral tunnel Fontan operation (LTFO) was performed in ten patients and extracardiac Fontan operation (ECFO) in five. A fenestration 4-5 mm in size was constructed in all patients with LTFO and in three of five patients with ECFO.

There was one intraoperative and one late death (total mortality 13%). The mean extubation time and hospital stay were 24 h and 21 days, respectively. Severe postoperative complications were observed in three patients (20%). Two LTFO patients out of a total of eight patients (53%) with perioperative arrhythmias received a permanent pacemaker due to bradyarrhythmia. During the median follow-up of 5.0 (range 2.3-10.1) years, four patients developed arrhythmias; one of them had new onset bradyarrhythmia after LTFO and required permanent pacemaker implantation. The median postoperative oxygen saturation was 93% (range 90-98%). NYHA class improved significantly in 12 survivors. Cardiac catheterization (0.5-4 years postoperatively, n=12) showed excellent Fontan hemodynamics in all patients.

The modified Fontan operation can be performed in adults with acceptable early and midterm mortality and morbidity and leads to either complete or marked relief of cyanosis and enhanced exercise tolerance in all survivors. Postoperative arrhythmias are one of the main drawbacks but the incidence of arrhythmias after ECFO seems to be lower. The long-term follow-up has yet to be established.