Can Fontan Conversion for Patients Without Late Fontan Complications be Justified?

The mid-term outcome of Fontan conversion compared with primary total cavopulmonary connection

BACKGROUND

The indication of Fontan conversion (FC) from atriopulmonary connection (APC) to total cavopulmonary connection (TCPC) is unclear. We sought to analyze the mid-term outcome of prophylactic and therapeutic Fontan conversion compared with that of primary TCPC.

METHODS

Patients with a univentricular heart who underwent cardiac catheterization at >18 years of age between July 2005 and July 2019 were included and divided into three groups: symptomatic APC patients who underwent therapeutic FC (t-FC, n = 13), asymptomatic APC patients after prophylactic FC (p-FC, n = 15), and patients who had primary TCPC procedure (pTCPC, n = 24).

RESULTS

The mean last follow up was at the age of 32.0 ± 7.8, 26.8 ± 3.8, and 27.3 ± 7 years (p = 0.07) in t-FC, p-FC, and pTCPC, respectively. There was no late death. All of t-FC and 12 (80%) of p-FC cases underwent concomitant arrhythmic surgery. Consequently, five and four patients in t-FC and p-FC groups required pacemaker implantations mostly due to sinus node dysfunction. Thromboembolism was seen in 2 cases in both t-FC (15%) and p-FC (13%), and 1 case in pTCPC (4%) (p = 0.50). The last cardiac catheterization was performed at the age of 29.5 ± 8.5, 24.6 ± 3.8, and 26.3 ± 7.1 years (p = 0.11) in t-FC, p-FC, and pTCPC patients, respectively. There was no significant difference in central venous pressure, aortic pressure, and cardiac index among the three groups. There was no late supraventricular tachyarrhythmic event seen in t-FC and p-FC, whereas two patients in pTCPC had newly developed atrial flutter.

CONCLUSIONS

FC is a safe and feasible procedure to bring APC patients back onto the same track of primary TCPC patients in terms of hemodynamics as well as arrhythmia. The antiarrhythmic procedure should be carefully chosen because sinus node dysfunction can frequently occur and FC itself would reduce the risk of arrhythmia.

Long-term therapeutic effect of Fontan conversion with an extracardiac conduit

OBJECTIVES

The aim of this study was to identify the long-term therapeutic effect of total cavopulmonary connection (TCPC) conversion with an extracardiac conduit.

METHODS

Between 1991 and 2014, 36 patients underwent TCPC conversion with an extracardiac conduit. Half of these patients were diagnosed with tricuspid atresia or its variant. The left ventricle was dominant in 26 patients (72.2%). Median age at conversion and interval from initial Fontan operation to conversion were 24.1 years (interquartile range 18.9-29.2) and 17.8 years (15.4-20.9), respectively. Surgical cryoablation was concomitantly performed in 32 patients (88.9%). Cardiac catheter examination was performed preoperatively (36 patients, 100%) and at 1 year (31 patients, 86%), 5 years (25 patients, 69%) and 10 years (13 patients, 36%) after TCPC conversion. Symptom-limited treadmill exercise with expired gas analysis was performed preoperatively (32 patients, 88.9%) and at 1 year (27 patients, 75.0%), 5 years (20 patients, 55.6%) and 10 years (12 patients, 33.3%) after conversion.

RESULTS

All patients received follow-up; the mean follow-up period was 8.2 ± 4.8 years. Actuarial survival rate, protein-losing enteropathy-free survival rate and rate of survival with sinus rhythm maintenance at 10 years were 79.2%, 67.8% and 48.5%, respectively. The survival curve declined steeply when the duration of Fontan circulation exceeded 25 years. New cases of protein-losing enteropathy developed postoperatively in 2 patients. Permanent pacemakers were implanted in 12 patients (33%), but atrial tachyarrhythmia was not sustained in any of the remaining patients. Pulmonary arterial pressure (11.0 ± 3.1 to 9.5 ± 3.6 mmHg, P = 0.003), pulmonary vascular resistance (2.1 ± 0.7 to 1.3 ± 0.5 WU/m2, P < 0.0001) and cardiac index (2.0 ± 0.3 to 2.9 ± 0.6 l/min/m2, P < 0.0001) significantly improved from preoperative evaluation to 1 year after the conversion, and these improvements were maintained during the entire follow-up period. Peak oxygen uptake remained unchanged from the preoperative evaluation (49.7 ± 11.5% predicted) to 1 year (52.5 ± 12.0%), 5 years (56.2 ± 9.6%) and 10 years (51.2 ± 9.4%) after conversion (P = 0.19).

CONCLUSIONS

Owing to its anti-arrhythmic effect and Fontan pathway recruitment effect, TCPC conversion with an extracardiac conduit prevented the natural decline of exercise tolerance that is seen in classic Fontan patients.

149 Fontan Conversions

Patients with a functionally univentricular heart who have had an atriopulmonary Fontan are at risk for atrial dilatation, atrial arrhythmias, and progressive circulatory failure. Between 1994 and 2018, we performed 149 Fontan conversions with arrhythmia surgery and epicardial pacemaker placement at Ann & Robert H. Lurie Children's Hospital of Chicago. This operation converts the atriopulmonary Fontan to an extracardiac Fontan that improves hemodynamics and controls the atrial arrhythmias. Operative mortality during that time was 2%, and freedom from death or heart transplant at 10 years is 84%. For properly selected patients, Fontan conversion improves both survival and quality of life. Patients with an atriopulmonary Fontan constitute an eroding population, as they face many comorbidities and have a decreased life expectancy without treatment; therefore, all patients with an atriopulmonary Fontan should be evaluated for this procedure.

Outcomes of the Conversion of the Fontan-Kreutzer Operation to a Total Cavopulmonary Connection for the Failing Univentricular Circulation

Background

The Fontan-Kreutzer procedure (FK) was widely performed in the past, but in the long-term generated many complications resulting in univentricular circulation failure. The conversion to total cavopulmonary connection (TCPC) is one of the options for treatment.

Objective

To evaluate the results of conversion from FK to TCPC.

Methods

A retrospective review of medical records for patients who underwent the conversion of FK to TCPC in the period of 1985 to 2016. Significance p < 0,05.

Results

Fontan-type operations were performed in 420 patients during this period: TCPC was performed in 320, lateral tunnel technique in 82, and FK in 18. Ten cases from the FK group were elected to conversion to TCPC. All patients submitted to Fontan Conversion were included in this study. In nine patients the indication was due to uncontrolled arrhythmia and in one, due to protein-losing enteropathy. Death was observed in the first two cases. The average intensive care unit (ICU) length of stay (LOS) was 13 days, and the average hospital LOS was 37 days. A functional class by New York Heart Association (NYHA) improvement was observed in 80% of the patients in NYHA I or II. Fifty-seven percent of conversions due to arrhythmias had improvement of arrhythmias; four cases are cured.

Conclusions

The conversion is a complex procedure and requires an experienced tertiary hospital to be performed. The conversion has improved the NYHA functional class despite an unsatisfactory resolution of the arrhythmia.