Impact of left ventricular rotational mechanics on clinical outcomes in patients with dilated cardiomyopathy
D M Toader, A Craciun-Mirescu, O Mirea, M Iovanescu, S Militaru, R P Tudorascu, M Chitu, I Donoiu, O Istratoaie, C MilitaruAbstract
Background
Dilated cardiomyopathy (DCM) defines left ventricular (LV) dilation and dysfunction in the absence of significant coronary artery disease or abnormal loading conditions. The studies identified LV rotational mechanics by speckle-tracking echocardiography (STE) as a sensitive marker of LV function.
Purpose
The study aimed to characterize rotational parameters and identify associations between these indices at discharge and complications, including cardiac rehospitalization and all-cause mortality, at two-year follow-up in patients with DCM and advanced-stage heart failure (HF).
Methods
The study included 109 patients with dilated DCM (47,7% of ischemic etiology), left ventricular ejection fraction (LVEF) below 40%, and NYHA class IV of HF. All patients underwent a comprehensive clinical, ECG, biological, and echocardiographic evaluation after compensation, before discharge, in accordance with the latest guidelines. We used an E95 machine for image acquisition and an ECHOPAC 206 for image postprocessing. LV rotational parameters were obtained using two-dimensional STE with quantitative analysis software. For LV rotational parameters, the images were acquired in the parasternal short-axis view at the basal (mitral valve) and apical (distal to the papillary muscles) levels. The measured parameters were LV basal and apical rotation, twist, and torsion.
Results
1. The patients with ischemic etiology of DCM presented lower values of rotational parameters compared with patients without coronary artery disease: basal rotation: -1.87 (SD 3.8) vs -3.34 (SD 6.4) (p =0.15), apical rotation: 2.78 (SD 5.94) vs 3.46 (SD 5.94) (p=0.55), twist: 2 (SD 6.64) vs 2.18 (SD 5.13) (p=0.87), torsion: 0.31 (SD 0.77) vs 0.41 (SD 0.58) (p= 0.44). 2. 2. 51 (46,78%) of patients were admitted for HF decompensation. Their rotational parameters compared with patients without hospitalization were: basal rotation: -1.37 (SD 3.96) vs. -4 (SD 6.47) (p= 0.001), apical rotation: 1.44 (SD 6.47) vs. 4.63 (SD 4.99) (p=0.004), twist 0.60 (SD 5.08) vs 3.39 (SD 6.3) (p=0.01), torsion 0.09 (SD 0.64) vs 0.42 (SD 0.8) (p=0.02). 3. 25 (30%) of patients died during follow-up. Their rotational parameters compared with no event DCM patients were: basal rotation: -0.91 (SD 4.83) vs -3.3 (SD 5.47) (p=0.05), apical rotation: 0.95 (SD 4.4) vs 3.7 (SD 6.18) (p=0.04), twist: -0.142 (SD 3.3) vs 2.98 (SD 6.32) (p=0.02), torsion: 0.01 (SD 0.49) vs 0.37 (SD 0.85) (p=0.04).
Conclusions
1. In patients with DCM, LV rotational parameters were not significantly different between ischemic and non-ischemic etiologies. 2. Reduced basal and apical rotation, twist, and torsion were associated with HF decompensation requiring hospitalization. 3. Impaired rotational mechanics were also associated with all-cause mortality during follow-up. These findings suggest that LV rotational parameters may serve as markers of disease severity and adverse prognosis in patients with DCM.LVEF measurement in a patient with DCMLV rotation by STE: a-normal subject; b-DCM