Abstract

Aims: To evaluate whether short-axis function plays a part in determining left ventricular (LV) geometric and functional improvement after cardiac resynchronisation therapy (CRT).

Methods and results: 39 patients who received CRT were enrolled. 2D speckle tracking echocardiography was performed at baseline and three months after CRT to assess mean systolic circumferential (ϵ-circum), radial (ϵ-radial) and longitudinal (ϵ-long) strain and torsion. Responders of reverse remodelling (n = 21) had higher baseline mean ϵ-circum than non-responders (p<0.05), who also had improvement in mean ϵ-circum and mean ϵ-radial (both p<0.05) after CRT. Also, the increase in mean ϵ-circum correlated with increase in ejection fraction (r = 0.57, p<0.001) and decrease in mid-cavity width (r = −0.52, p = 0.001). A baseline mean ϵ-circum of ⩾6.5% predicted a gain in ejection fraction ⩾5%, with a sensitivity of 73% and a specificity of 71%. The baseline ϵ-long was not different between the two groups, and remained unchanged after CRT. The torsion did not improve in responders, but was worsened in non-responders (p<0.05).

Conclusions: The improvement of LV short-axis function but not long-axis function or torsion contributes to the improvement in LV global function and geometry at three-month follow up. A relatively preserved mean ϵ-circum of ⩾6.5% might be useful to predict favourable responses after CRT.