Premium
Mechanical dyssynchrony or myocardial shortening as MRI predictor of response to biventricular pacing?
Author(s) -
Rüssel Iris K.,
Zwanenburg Jaco J.M.,
Germans Tjeerd,
Marcus J. Tim,
Allaart Cornelis P.,
de Cock Carel C.,
Götte Marco J.W.,
van Rossum Albert C.
Publication year - 2007
Publication title -
journal of magnetic resonance imaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.563
H-Index - 160
eISSN - 1522-2586
pISSN - 1053-1807
DOI - 10.1002/jmri.21133
Subject(s) - cardiology , medicine , ventricle , cardiac resynchronization therapy , qrs complex , ventricular dyssynchrony , heart failure , ejection fraction
Purpose To investigate whether mechanical dyssynchrony (regional timing differences) or heterogeneity (regional strain differences) in myocardial function should be used to predict the response to cardiac resynchronization therapy (CRT). Materials and Methods Baseline mechanical function was studied with MRI in 29 patients with chronic heart failure. Using myocardial tagging, two mechanical dyssynchrony parameters were defined: the standard deviation (SD) in onset time ( T onset ) and in time to first peak ( T peak,first ) of circumferential shortening. Electrical dyssynchrony was described by QRS width. Further, two heterogeneity parameters were defined: the coefficient of variation (CV) in end‐systolic strain and the difference between peak septal and lateral strain (DiffSLpeakCS). The relative increase in maximum rate of left ventricle pressure rise (d P /d t max ) quantified the acute response to CRT. Results The heterogeneity parameters correlated better with acute response (CV: r = 0.58, DiffSLpeakCS: r = 0.63, P < 0.005) than the mechanical dyssynchrony parameters (SD( T onset ): r = 0.36, SD( T peak,first ) r = 0.47, P = 0.01, but similar to electrical dyssynchrony ( r = 0.62, P < 0.001). When a heterogeneity parameter was combined with electrical dyssynchrony, the correlation increased ( r > 0.70, P incr < 0.05). Conclusion Regional heterogeneity in myocardial shortening correlates better with response to CRT than mechanical dyssynchrony, but should be combined with electrical dyssynchrony to improve prediction of response beyond the prediction from electrical dyssynchrony only. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.