The noncompaction of the left ventricular myocardium: our paediatric experience.

OBJECTIVES

The noncompaction of the left ventricular myocardium is a rare congenital heart disease, characterized by an excessive prominence of trabecular meshwork, spaced out by deep intertrabecular recesses, consequent to the arrest of the normal myocardium embryogenesis. Although there are numerous descriptions, the physiopathological effects of the structural alterations, just like the clinical spectrum and the evolution of the disease, are not totally clarified. In the present study, we have evaluated the natural history of the disease, the familial incidence and the alterations of the systolic and diastolic function.

METHODS

We collected a series of 21 young patients who were affected by noncompaction of left ventricular myocardium. In all cases, a diagnosis was echocardiographically made on the basis of a reported spongy/compacted ratio > 2 in one or more segments of the left ventricle. Thirteen patients were male and eight were female, with a mean age of 12.7 years (range 21 days to 27 years). The average follow-up time was 7.8 years (range 1-18 years); all patients were periodically tested by ECG Holter and two-dimensional and Doppler echocardiogram. In 14 patients, the last echocardiographic evaluation included the analysis of tissue Doppler imaging (TDI).

RESULTS

The noncompaction of left ventricular myocardium was isolated in nine cases and associated with a structural cardiopathy in 12 cases: with atrial septal defect in four cases, ventricular septal defect in four cases, aortopulmonary window in one case, aortic coarctation in one case and bicuspid aortic valve in one case. One case presented a type Kent ventricular pre-excitation. Twelve cases were symptomatic at the moment of the diagnosis (for heart failure in 11 cases and for syncope in one case). Nine cases were asymptomatic and the diagnosis was made during a family screening or occasionally. In ten of the 11 subjects affected by congestive heart failure, medical therapy re-established a good haemodynamic balance (in two cases, it was possible to suspend the therapy). In one case with congestive heart failure and pulmonary hypertension in New York Heart Association class III, we recommended heart transplantation. We did not find any dysrhythmia in any of the cases. Diastolic function impairment, tested by transmitral blood pressure monitoring and TDI, was found in seven of 14 patients, all with reduced left ventricular contractility.

CONCLUSIONS

We noticed a considerable variability of clinical presentation in our cases, according to the number of the ventricular segments affected by the anomaly. According to our data, middle-term prognosis appears to be better than that previously reported in the literature. We found a reduction of the systolic function only in 50% of cases, all with severe involvement of the apical and postero-lateral segments. Diastolic function was compromised only in those patients with severe impairment of systolic function.