Reversal of cardiac dysfunction after enzyme replacement in patients with infantile-onset Pompe disease.

OBJECTIVE

To compare the effects of enzyme replacement therapy (ERT) on cardiac performance in symptomatic and symptom-free infants with Pompe disease.

STUDY DESIGN

Patients diagnosed between 1983 and 2008 were identified. Before the initiation of ERT, systolic dysfunction appeared only in patients > or = 5 months; thus we used this cut-point in age to divide clinically symptomatic patients into early and late treatment groups (Clin-E and Clin-L). Newborn screening (NBS) identified symptom-free patients.

RESULTS

Among a total of 40 patients, 14 received ERT: 5 in the Clin-L, 4 in the Clin-E, and 5 in the NBS groups. All patients showed cardiomegaly, hypertrophic myocardium, and elevated B-type natriuretic peptide (measured in the Clin-E and NBS groups). ERT improved the survival and outcomes. Regressed myocardial hypertrophy and lowered B-type natriuretic peptide level occurred after 1 to 6 months of ERT. Nonetheless, there were 2 deaths and 2 survivors requiring ventilator support in the Clin-L group. Despite the regressed QRS voltage and shortened QT dispersion, life-threatening arrhythmias were still observed in 3, but none in the NBS group.

CONCLUSION

ERT may restore the cardiac function in both symptomatic and symptom-free patients, but the beneficial effect may be unpredictable if given after the age of 5 months.