RESUMO
OBJECTIVE: Parents and their infants with complex congenital heart disease (CHD) face relational challenges, including marked distress, early separations, and infant hospitalizations and medical procedures, yet the prevalence of parent-infant interaction difficulties remains unclear. Using a standardized observational paradigm, this study investigated mother-infant dyadic synchrony, interactional patterns, and associated predictors in mother-infant pairs affected by CHD, compared with typically-developing pairs. METHODS: In this prospective, longitudinal cohort study, mothers and their infants requiring cardiac surgery before age 6-months (n=110 pairs) and an age- and sex-matched Australian community sample (n=85 pairs) participated in a filmed, free-play interaction at 6.9±1.0 months. Mother-infant dyadic synchrony, maternal and infant interactional patterns, and relational risk were assessed using the Child-Adult Relationship Experimental (CARE) Index. Maternal and infant predictors were assessed at 32 weeks gestation, 3- and 6-months postpartum. RESULTS: Most mother-infant interactions were classified as "high risk" or "inept" (cardiac: 94%, control: 81%; p=.007). Dyadic synchrony (p<.001), maternal sensitivity (p=.001), and infant cooperativeness (p=.001) were lower for cardiac than control pairs. Higher maternal traumatic stress at 6-months postpartum predicted lower dyadic synchrony for mother-infant pairs affected by CHD (B=-.04, p=.03). Dyadic synchrony was higher among older infants in the total (B=.40, p=.003) but not cardiac sample (B=.24, p=.06). CONCLUSIONS: Relational difficulties were almost universal among mother-infant pairs affected by CHD and were also high in the Australian community sample. Widespread education initiatives are recommended to increase awareness of heightened mother-infant relational risk in congenital heart care and well-child settings, alongside relationally-focused prevention and early intervention programs.