Cardiac Resynchronization Therapy Response Assessment with Electromechanical Activation Mapping within 24 Hours of Device Implantation: A Pilot Study - 02/07/21
Abstract |
Background |
Cardiac resynchronization therapy (CRT) response assessment relies on the QRS complex narrowing criterion. Yet one third of patients do not improve despite narrowed QRS after implantation. Electromechanical wave imaging (EWI) is a quantitative echocardiography-based technique capable of noninvasively mapping cardiac electromechanical activation in three dimensions. The aim of this exploratory study was to investigate the EWI technique, sensitive to ventricular dyssynchrony, for informing CRT response on the day of implantation.
Methods |
Forty-four patients with heart failure with left bundle branch block or right ventricular (RV) paced rhythm and decreased left ventricular ejection fraction (LVEF; mean, 25.3 ± 9.6%) underwent EWI without and with CRT within 24 hours of device implantation. Of those, 16 were also scanned while in left ventricular (LV) pacing. Improvement in LVEF at 3-, 6-, or 9-month follow-up defined (1) super-responders (ΔLVEF ≥ 20%), (2) responders (10% ≤ ΔLVEF < 20%), and (3) nonresponders (ΔLVEF ≤ 5%). Three-dimensionally rendered electromechanical maps were obtained under RV, LV, and biventricular CRT pacing conditions. Mean RV free wall and LV lateral wall activation times were computed. The percentage of resynchronized myocardium was measured by quantifying the percentage of the left ventricle activated within 120 msec of QRS onset. Correlations between percentage of resynchronized myocardium and type of CRT response were assessed.
Results |
LV lateral wall activation time was significantly different (P ≤ .05) among all three pacing conditions in the 16 patients: LV lateral wall activation time with CRT in biventricular pacing (73.1 ± 17.6 msec) was lower compared with LV pacing (89.5 ± 21.5 msec) and RV pacing (120.3 ± 17.8 msec). Retrospective analysis showed that the percentage of resynchronized myocardium with CRT was a reliable response predictor within 24 hours of implantation for significantly (P ≤ .05) identifying super-responders (n = 7; 97.7 ± 1.9%) from nonresponders (n = 17; 89.9 ± 9.9%).
Conclusion |
Electromechanical activation mapping constitutes a valuable three-dimensional visualization tool within 24 hours of implantation and could potentially aid in the timely assessment of CRT response rates, including during implantation for adjustment of lead placement and pacing outcomes.
Le texte complet de cet article est disponible en PDF.Graphical abstract |
Highlights |
• | LWAT (2D and 3D) can significantly differentiate BiV pacing conditions. |
• | EWI provides 3D visualization of ventricular dyssynchrony change directly after CRT. |
• | EWI can quantify amount of myocardium resynchronized within 24 hours of implantation. |
• | Post-CRT %RMLV is a reliable predictor to distinguish super- from nonresponders. |
Keywords : Echocardiography, Electromechanical wave imaging, Cardiac resynchronization therapy, Ventricular resynchrony assessment, Response prediction, Heart failure
Abbreviations : 2D, 3D, BiV, CRT, EWI, HF, LBBB, LV, LVEF, LWAT, %RM, RV, RWAT
Plan
This study was supported in part by the National Institutes of Health, United States (grants R01 HL114358, R01 EB006042 and R01 HL140646). |
|
Conflicts of interest: None. |
Vol 34 - N° 7
P. 757 - juillet 2021 Retour au numéroBienvenue sur EM-consulte, la référence des professionnels de santé.
L’accès au texte intégral de cet article nécessite un abonnement.
Déjà abonné à cette revue ?