The influence of left bundle branch-block and cardiac dyssynchrony on 2D-strain parameters in patients with heart failure complicating ischemic cardiomyopathy.

UNLABELLED: Coronary artery disease is the underlying cause in approximately two-thirds of patients with heart failure. Torsional and longitudinal deformations are essential components of left ventricular (LV) performance. Electric conduction defects can reduce LV ejection fraction (LVEF) and decrease cardiac output.

AIM: To investigate the influence of left bundle branch-block (LBBB) and cardiac dyssynchrony on 2D-strain parameters in patients with HF complicating ischemic cardiomyopathy.

METHODS

We analyzed 106 consecutive patients with HF complicating ischemic cardiomyopathy, in sinusal rhythm. LV strain, LV twist and LV torsion were measured by echocardiographic 2D-strain imaging. LV dyssynchrony was assessed using validated tissue Doppler parameters. Patients were divided into three groups: HF with normal LVEF (group 1), HF with reduced LVEF without LBBB (group 2) and with LBBB (group 3).

RESULTS

LVEF, LV strain, LV torsion and LV twist were significantly better in group 1 (each p < 0.01). In group 3, LV torsion and LV twist were significantly lower compared to group 2 (0.80 +/- 0.4 vs. 1.21 +/- 0.23 degrees/cm, p = 0.007, and 5.18 +/- 2.4 vs. 8.31 +/- 1.5 degrees, p = 0.004, respectively), but LV strain and LVEF were not different between group 3 and 2 (-4.91 +/- 2.3 vs. -6.28 +/- 1.8%, p = 0.056, and 30.6 +/- 8.8 vs. 34.4 = 8.3%, p = 0.11, respectively). Cardiac dyssynchrony induces a reduction of all 2D-strain analyzed parameters (each p < 0.05).

CONCLUSION

In HF complicating ischemic cardiomyopathy, LBBB and cardiac dyssynchrony induce a reduction of LV strain, torsion and twist. In patients with reduced LVEF, LBBB induces predominantly a significant reduction ofLV torsion and LV twist, while LV strain was apparently not influenced.