A non-invasive method of assessing cardiac electrical synchrony is described.
•Synchrony over a range of cardiac resynchronization device settings is mapped.
•Optimal device settings can be found, potentially improving patient outcomes.
•Timing of RV-paced, LV-paced and native electrical wavefronts can be quantified.
•Lack of resynchronization over the entire map suggests poor lead position.
AbstractPurposeThere is no clinical methodology for quantification or display of electrical dyssynchrony over a wide range of atrial-ventricular delays (AVD) and ventricular-ventricular delays (VVD) in patients with cardiac resynchronization therapy (CRT). This study aimed to develop a new methodology, based on wavefront fusion, for mapping electrical synchrony.
MethodsA cardiac resynchronization index (CRI) was measured at multiple device settings in 90 patients. Electrical dyssynchrony maps (EDM) were constructed for each patient to display CRI at any combination of AVD and VVD. An optimal synchrony line (OSL) depicted the AVD/VVD combinations producing the highest CRIs. Fusion of right ventricular paced (RVp), left ventricular paced (LVp), and native wavefront offsets were calculated.
ResultsCRI significantly increased (p < 0.0001) from 58.0 ± 28.1% at baseline to 98.3 ± 1.7% at optimized settings. EDMs in patients with high-grade heart block (n = 20) had an OSL parallel to the simultaneous biventricular pacing (BiVPVV-SIM) line with leftward shift across all AVDs (RVp-LVpOFFSET = 50.5 ± 29.8 ms). EDMs in patients with intact AV node conduction (n = 64) had an OSL parallel to the BiVPVV-SIM line with leftward shift at short AVDs (RVp-LVpOFFSET = 33.4 ± 23.3 ms), curvilinear at intermediate AVDs (triple fusion), and vertical at long AVDs (native-LVpOFFSET = 85.2 ± 22.8 ms) in all patients except those with poor LV lead position (n = 6).
ConclusionA new methodology is described for quantifying and graphing electrical dyssynchrony over a physiologic range of AVDs/VVDs. This methodology offers a noninvasive, practical, clinical approach for measuring electrical synchrony that could be applied to optimization of CRT devices.
KeywordsCardiac resynchronization therapy
Electrical dyssynchrony
Optimization
Electrocardiography
Wavefront fusion
AbbreviationsA-LVINTERVALatrial sensed/paced to LV paced interval
A-RVINTERVALatrial sensed/ paced to RV paced interval
ApRVsatrial paced RV sensed
AsRVsatrial sensed RV sensed
BiVPVV-SIMsimultaneous biventricular pacing
BiVPVV-SEQsequential biventricular pacing
CRIcardiac resynchronization index
EDMelectrical dyssynchrony mapping
L-IVCDinterventricular conduction delay with LV activation delay
OSLoptimal synchrony line
Native-LVpOFFSETNative to LV paced timing offset
Native-RVpOFFSETNative to RV paced timing offset
RVp-LVpOFFSETRV paced to LV paced timing offset
© 2022 The Authors. Published by Elsevier Inc.
留言 (0)