Background: Left ventricular (LV) torsion is a key parameter in cardiac function and predicts functional capacity (FC) more appropriately than LV ejection fraction (EF). We sought to investigate LV torsion as a marker of hospitalization for worsening heart failure (HF) in non-ischemic dilated cardiomyopathy (DCM) patients. Methods and Results: The 91 outpatients with newly diagnosed DCM (53±13 years, 20% female) were evaluated with 3D speckle-tracking imaging and followed up for 12 months; 43 healthy sex- and age-matched volunteers served as controls. LV torsion, LVEF, right ventricular function, LV global longitudinal (GLS) and circumferential (GCS) strain values, peak oxygen uptake (peak V̇O2) from FC and B-type natriuretic peptide levels were measured at baseline. Peak V̇O2correlated successively with LV torsion, diastolic filling and GCS (r=0.70, -0.52 and -0.41, P<0.01) disclosing the central role of LV torsion. During follow-up (median 272 days), 24 (26%) cardiac events occurred. A reduced LV torsion (<0.59 degrees/cm) predicted cardiac events similar to a reduced peak V̇O2(<19 mL/kg/min) (unadjusted hazard ratio 6.41 and 5.90, P<0.001). LV torsion provided a significant incremental value over right ventricular function and peak V̇O2(C-index: 0.85, P=0.02).
Conclusions: The results demonstrated a clear relation between LV torsion and disease severity, suggesting that LV torsion has additional prognostic relevance in DCM patients.
Keywords: 3D speckle-tracking echocardiography; Heart failure; Left ventricle; Non-ischemic dilated cardiomyopathy; Torsion.