Left ventricular torsion as a prognostic marker in patients with dilated cardiomyopathy

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background Left ventricular (LV) torsion is the wringing motion of the ventricle around its long axis induced by contracting obliquely oriented myofibers in the LV wall and it predicts functional capacity more appropriately than LV ejection fraction (EF). Purpose This study was intended to evaluate reduced LV torsion as a potential marker of disease severity and a predictor of hospitalization for worsening heart failure in patients with non-ischemic dilated cardiomyopathy (DCM). Methods This was a single center prospective observational study wherein 127 patients with a diagnosis of non-ischemic DCM with a LVEF <50% were enrolled. In addition, 48 age and sex matched healthy individuals without any prior history of cardiovascular diseases and normal LVEF were enrolled as controls. All these patients underwent detailed clinical assessment including symptomatology, NYHA function class evaluation and routine blood investigations including CPK-MB levels. In addition, all enrolled subjects underwent 2D transthoracic echocardiography along with speckle tracking imaging to determine the LV global longitudinal strain (LV-GLS), LV twist and LV torsion. Based on the measurement of LV torsion, patients were stratified into two groups: preserved LV torsion (>0.59 degrees/cm) and reduced LV torsion (<0.59 degrees/cm). These patients were followed up for six months in terms of MACE events. Results Reduced LV torsion was reported in 52/127 (40.9%) patients with DCM. These patients had significantly lower LVEF, altered LV geometry (base-apical distance) and higher levels of CPK-MB. Additionally, patients with reduced LV torsion had a worsened functional class and a greater frequency of hospital admissions (34 vs 6; P<0.001) over 6 months of follow-up as compared to those with preserved LV torsion. Multivariate logistic regression reported reduced LV torsion to be an independent predictor of MACE events over six months of follow-up (OR:4.20; P=0.001). Conclusion Findings from our study suggested that LV torsion can serve as an additional prognostic marker in patients with non-ischemic DCM.