Regional Myocardial Systolic Function Assessed by Strain Tissue Doppler Imaging in Patients With Isolated Noncompaction of Left Ventricular Myocardium: A Study of Two Cases

Abstract

Isolated noncompaction of the left ventricular myocardium (INVM) is associated with a high incidence of heart failure. However, it is difficult to determine accurately left ventricular (LV) systolic function because of the trabeculated ventricles. The purpose of this study was to clarify whether strain imaging could detect regional myocardial systolic function in 2 patients with INVM. We recorded myocardial strain profiles at the basal, mid-, and apical portions of the LV free wall and ventricular septum (VS) in the apical LV long-axis view. Case 1 (15-year-old male) was referred to our hospital because of ECG abnormalities. Case 2 (83-year-old female) was admitted to our hospital for congestive heart failure. Two-dimensional echocardiography in both patients showed numerous prominent trabeculations and deep intertrabecular recesses at the apex of the LV wall. Because of the trabeculations, it was difficult to determine accurately LV ejection fraction by 2-dimensional echocardiography. The percent fractional shortening of the LV (%FS) in both cases was within a normal range. However, the peak systolic strains at the apical, mid-, and basal portions of the LV free wall were lower in Case 2 (-12, -12, and -11%, respectively) than in Case 1 (-33, -37, and -37%, respectively). The peak systolic strains at the apical, mid-, and basal portions of the VS were also lower in Case 2 (-11, -16, and -11%, respectively) than in Case 1 (-27, -27, and -29%, respectively). We conclude that strain measurements are useful for evaluating regional myocardial systolic function in patients with INVM.