Early pacing in a child with Lodder–Merla syndrome and progressive sinus node dysfunction: a case report

Cardiac involvement in GNB5-related disorders may be overshadowed by the dominant neurodevelopmental presentation. This case highlights an important cardiovascular dimension to the syndrome. SND can be progressive and life-threatening, requiring early recognition and individualized pacing strategies. In young children with significant comorbidities, classic bradyarrhythmia symptoms may be absent, underscoring the need for a high index of suspicion and proactive rhythm surveillance to enable timely intervention.