Longitudinal Somatic Growth in Patients with Complex Univentricular Heart Disease Undergoing Fontan Operation: Relation to Suboptimal Outcomes

Background: Children with univentricular heart disease have been reported to have considerable somatic growth retardation. We sought to characterize longitudinal somatic growth in patients with univentricular heart disease undergoing staged palliation and to explore relationships of somatic growth with outcome.

Method: From 428 patients who underwent Fontan operations in our institutions from 1989 to 2020, a total of 401 were included in the study, excluding 27 patients who were operated as adults. Anthropometric data and additional clinical data from stage 2 palliation, Fontan operation and long-term follow-up were recorded. Z-scores for weight, height and body mass index (BMI) were calculated from recent national reference charts.

Results: Stage 2 palliation was performed at a median of 0.7 [IQR: 0.5, 1.5] and the Fontan operation at 3.6 [IQR: 2.8, 4.7] years, respectively. Overall median Z-Scores at stage 2 palliation were −1.55 [IQR: −2.32, −0.63] for weight, −1.15 [IQR: −2.09, 0.07] for height and −1.19 [IQR: −2.01, −0.18] for BMI. There was a significant weight increase until Fontan operation to a median Z-score of −1.01 (p < 0.001), whereas Z-scores remained stable thereafter throughout follow-up (all p > 0.05). Similar, a significant height increase was observed until Fontan operation to a median Z-score of −0.61 (p < 0.001), whereas no additional catch-up growth was observed thereafter (all p > 0.05).

There was a significant association of early Fontan failure (<1 year postoperatively) and late Fontan failure with reduced weight Z-scores at stage 2 palliation (non-failing −1.47 [IQR: −2.19, −0.62] vs. early failure −1.87 [IQR: −3.78, −1.09], p = 0.006, vs. late failure −2.38 [IQR: −4.05, −0.33], p = 0.043) or at Fontan operation (non-failing −0.88 [IQR: −1.82, −0.08] vs. early failure −1.59 [IQR: −3.31, −0.92], p < 0.001, vs. late failure −1.75 [IQR: −3.05, −0.88], p < 0.001). Moreover, lower weight Z-scores at Fontan operation correlated with increased postoperative hospital stay (r = −0.13, p = 0.013).

Conclusion: Abnormal anthropometry is common in patients with univentricular heart disease throughout staged palliation. Despite catch-up growth after Fontan operation, patients’ weight and height frequently remain below average. Low weight Z-scores prior to Fontan operation, which might result from more pronounced preoperative hemodynamic impairments, are associated with adverse outcomes. Thus, weighted Z-scores represent an important detail in evaluating suitability for Fontan operation.

Publication History

Article published online:
28 January 2023