Sveric KM, Ulbrich S, Rady M, Ruf T, Kvakan H, Strasser RH, Jellinghaus S

Circ J. 2017 Mar 24;81(4):529-536. doi: 10.1253/circj.CJ-16-0965. Epub 2017 Jan
24. (Article from Dresden)

BACKGROUND: LV twist has a key role in maintaining left ventricular (LV)
contractility during exercise. The purpose of this study was to investigate LV
torsion instead of twist as a surrogate marker of peak oxygen uptake (peak V̇O2)
assessed by cardiopulmonary exercise testing (CPET) in patients with non-ischemic
dilated cardiomyopathy (DCM).Methods and Results:We evaluated 45 outpatients with
DCM (50±12 years, 24% females) with 3D speckle-tracking electrocardiography prior
to CPET. LV torsion, LV ejection fraction (EF), LV diastolic function, LV global
longitudinal (GLS) and circumferential (GCS) strain were quantified. A reduced
functional capacity (FC) was defined as a peak V̇O2<20 mL/kg/min. LV torsion correlated most strongly with peak V̇O2(r=0.76, P<0.001). LV torsion instead of twist was an independent predictor of peak V̇O2(B: 0.59 to 0.71, P<0.001) in multivariable analyses. Impaired LV torsion <0.61 degrees/cm was able to predict a reduced FC with higher sensitivity and specificity (0.91 and 0.81; area under the curve (AUC): 0.88, P<0.001) than LV EF, GLS or GCS (AUC 0.64, 0.63 and 0.66; P<0.05 for differences in AUC). CONCLUSIONS: Peak V̇O2 correlated more strongly with LV torsion than with LV diastolic function, LV EF, GLS or GCS. LV torsion had high accuracy in identifying patients with a reduced FC.