Reduced regional systolic function is not confined to the noncompacted segments in noncompaction cardiomyopathy
Background: Isolated ventricular noncompaction (IVNC) is a relatively rare genetic primary cardiomyopathy. The aim of the present study was to investigate with regional real-time three-dimensional echocardiographic analysis whether there is a difference between the contribution of noncompacted and compacted left ventricular (LV) segments to global LV dysfunction in patients with IVNC. Methods: The study comprised 289 segments of 17 patients with stringent diagnostic criteria for IVNC. Their results were compared to 153 segments of 9 control subjects. The systolic performance of compacted and noncompacted LV segments was assessed using the wall motion score during 2D echocardiography. The 3D images were acquired with a RT3DE system with X4 matrix-array transducer and were used for the regional volume measurements. Results: Wall motion score index was markedly abnormal in the compacted LV segments of IVNC patients but significantly less abnormal compared to the noncompacted segments (2.21 ± 0.63 vs. 2.01 ± 0.74, p < 0.05). No relationship was found between the number of noncompacted segments per patient and LV ejection fraction or end-diastolic volume. In the IVNC patients, noncompacted and compacted LV segments had comparable increased 3D regional volumes and reduced systolic function. Conclusions: These results suggest that systolic LV dysfunction observed in IVNC is not confined to noncompacted LV segments.