Aim: Our objective was to evaluate regional systolic myocardial contraction properties along the long and short axes of the left ventricle (LV) in patients with isolated LV non-compaction (IVNC).
Methods and results: Pulsed tissue Doppler imaging (TDI) was used to record myocardial velocities along these axes in 25 patients with IVNC (10 asymptomatic-LV ejection fraction [LVEF] > or = 50%; 15 symptomatic-LVEF < 50%) and 15 healthy controls. In all cases, the systolic velocity pattern featured 2 distinct peaks (SW1, SW2). These peak velocities and the intervals from the electrocardiographic Q wave to each peak (Q-SW1, Q-SW2) were recorded for each axis, and group means were calculated. The asymptomatic group displayed significantly higher long axis SW2 and significantly longer long axis Q-SW1 than the controls. The symptomatic group had significantly lower SW1 and SW2 on both axes and significantly longer short axis Q-SW1 than the asymptomatic group and the controls. Long axis Q-SW1 and short axis Q-SW1 in the symptomatic group were significantly longer than the corresponding control findings, but were not significantly different from the corresponding asymptomatic group findings.
Conclusion: In conclusion, patients with IVNC exhibit distinct systolic myocardial shortening velocities along the long and short axes of the LV. Further, these pulsed TDI findings suggest that asymptomatic patients (those with normal LVEF) have subclinical myocardial dysfunction.