Impact of Veno-venous Collaterals on Outcome after the Total Cavopulmonary Connection

Background: Although outcomes after total cavopulmonary connection (TCPC) have improved continuously, there still remain Fontan-specific late complications. The development of veno-venous collaterals (VVCs) is one of these complications that demonstrate cyanosis and require interventional therapy. The purpose of this study is to evaluate the prevalence of VVCs after TCPC and to analyze their impact on outcomes.

Methods: We performed a retrospective analysis of 635 patients with univentricular heart who underwent TCPC between January 1994 and December 2022. Patients who underwent TCPC conversion from classic Fontan procedure were excluded from this study. Development of VVCs after TCPC was retrospectively depicted using cardiac catheterization records. The incidence of VVCs was evaluated, the impact of VVCs on outcomes was identified, and the risks for the development of VVCs were analyzed using linear regression models.

Results: Median age and median weight at TCPC were 2.3 (interquartile ranges (IQR): 1.8–3.3) years, and 12.0 (10.7–14.0) kg, respectively. Prior bidirectional cavopulmonary shunt (BCPS) was performed in 586 (92.3%) patients at a median age of 5.3 (3.6–9.9) months. The most frequent diagnosis was HLHS in 173 patients. VVCs were found in 94 (14.8%) patients at a median of 2.8 (0.1–11.8) years after TCPC. The incidence of VVCs was similar between the dominant right (14.7%) and left (14.9%) ventricle (p = 0.967). Mean pulmonary artery pressure (16.2 vs. 16.0 mm Hg, p = 0.902), left atrial pressure (5.5 vs. 5.7 mm Hg, p = 0.480), transpulmonary gradient (4.0 vs. 3.8 mm Hg, p = 0.277) and arterial oxygen saturation (81.4 vs. 82.6%, p = 0.480) before TCPC were similar between the patients with and without VVCs. The number of palliation was identified as a risk for the development of VVCs after TCPC (p = 0.012, odds ratio: 1.350, confidence interval: 1.069–1.704). There was no impact of VVCs on survival after TCPC (96 vs. 94% at 10 years, p = 0. 635). Whereas, there was a significant difference in freedom from protein losing enteropathy (PLE)/plastic bronchitis (PB) in patients with and without VVCs (82 vs. 90% at 10 years, p = 0.015). Interventional closure of VVCs was performed in 61 (9.6%) patients at a median 8.9 (0.6–15.1) years after TCPC.

Conclusion: The prevalence of developing VVCs after TCPC was 15%. VVCs had no impact on transplant-free survival following TCPC, whereas patients who had VVCs demonstrated lower freedom from PLE/PB after TCPC.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
13 February 2024