RT Journal Article
SR Electronic
T1 Mechanical dyssynchrony is additive to ECG criteria and independently associated with reverse remodelling and clinical response to cardiac resynchronisation therapy in patients with advanced heart failure
JF Open Heart
JO Open Heart
FD British Cardiovascular Society
SP e000246
DO 10.1136/openhrt-2015-000246
VO 2
IS 1
A1 Alan J Bank
A1 Ryan M Gage
A1 Josef J Marek
A1 Toshinari Onishi
A1 Kevin V Burns
A1 David Schwartzman
A1 Samir Saba
A1 John Gorcsan III
YR 2015
UL http://openheart.bmj.com/content/2/1/e000246.abstract
AB Background QRS duration and morphology are known established predictors of cardiac resynchronisation therapy (CRT) response, whereas mechanical dyssynchrony is not. Our aim was to determine if mechanical dyssynchrony provides independent prognostic information on CRT response.Methods We studied 369 consecutive patients with heart failure (HF) with low ejection fraction (EF) and widened QRS receiving CRT. Radial dyssynchrony (septal-posterior radial peak strain delay ≥130 ms by speckle tracking) assessment was possible in 318 patients (86%). Associations with left ventricular end-systolic volume (LVESV) changes were examined using linear regression, and clinical outcomes analysed using Cox regression adjusted for multiple established outcome correlates.Results Patients with radial dyssynchrony before CRT (64%) had greater improvements in EF (8.8±9.4 vs 6.1±9.7 units, p=0.04) and LVESV (−30±41 vs −10±30 mL, p<0.01). Radial dyssynchrony was independently associated with reduction in LVESV (regression coefficient −10.5 mL, 95% CI −20.5 to −0.5, p=0.040) as was left bundle-branch block (−17.7 mL, −27.6 to −7.7, p=0.001). Patients with radial dyssynchrony had a 46% lower incidence of death, transplant or implantation of a left ventricular assist device (adjusted HR 0.54, 95% CI 0.31 to 0.92, p=0.02) and a 39% lower incidence of death or HF hospitalisation (0.61, 0.40 to 0.93, p=0.02) over 2 years.Conclusions Radial dyssynchrony was associated with significant improvements in LVESV and clinical outcomes following CRT and is independent of QRS duration or morphology, and additive to current ECG selection criteria to predict response to CRT.