Maternal Diabetes Mellitus is the Condition Associated with Neonatal Hypertrophic Cardiomyopathy
The answer is B - Diabetes Mellitus (DM). Maternal diabetes, both pregestational and gestational, is well-established as the primary maternal condition causing transient hypertrophic cardiomyopathy in neonates 1.
Pathophysiology and Mechanism
Infants of diabetic mothers (IDMs) develop hypertrophic cardiomyopathy through hyperinsulinemia-driven mechanisms 2:
- Fetal hyperinsulinemia acts as a growth factor, causing myocardial hypertrophy, particularly of the interventricular septum 2, 3
- Elevated neonatal IGF-I levels are significantly associated with fetal HCM in diabetic pregnancies (80 ± 16 ng/mL in those with HCM vs 61 ± 18 ng/mL without, P < .001) 4
- The hypertrophy can affect both ventricles but most commonly involves septal hypertrophy 3, 5
Clinical Presentation and Prevalence
The spectrum of disease varies considerably 2, 3:
- Hypertrophic cardiomyopathy occurs in 38% of infants of diabetic mothers 3
- Most cases are asymptomatic and detected incidentally on echocardiography 2
- Severe cases can present with congestive heart failure, hydrops fetalis, or even fetal death 6, 5
- Both Type 1 diabetes and gestational diabetes can cause significant fetal cardiac disease 5
Prognosis and Resolution
The condition is generally transient and benign 2, 6:
- Hypertrophy typically normalizes within 6 weeks to 6 months after birth without specific treatment 2, 5
- In one study, only 8% had persistent HCM at 6 months of age 4
- Fatal cases are rare but have been documented, particularly when associated with hydrops fetalis 6
Impact of Glycemic Control
Careful diabetic management during pregnancy significantly reduces the severity of hypertrophic cardiomyopathy 2:
- IDMs of mothers with well-controlled diabetes continue to show mild generalized hypertrophy compared to controls 2
- However, none developed symptomatic congestive heart failure with good maternal glycemic control 2
- This supports aggressive glucose management throughout pregnancy 2
Why the Other Options Are Incorrect
- SLE (Option A): Not associated with neonatal hypertrophic cardiomyopathy; maternal SLE is associated with congenital heart block in neonates, not HCM
- Glycogen storage disease (Option C): This is a neonatal/fetal genetic condition, not a maternal condition. While glycogen storage diseases can cause HCM, they are inherited metabolic disorders of the infant itself 1