Electrocardiographic correlates of mechanical dyssynchrony in recipients of cardiac resynchronization therapy devices.
BACKGROUND
The relationship between electrical and mechanical indices of cardiac dyssynchronization in systolic heart failure (HF) remains poorly understood.


OBJECTIVE
We examined retrospectively this relationship by using the daily practice tools in cardiology in recipients of cardiac resynchronization therapy (CRT) systems.


METHODS
We studied 119 consecutive patients in sinus rhythm and QRS ≥ 120 ms (mean: 160 ± 17 ms) undergoing CRT device implantation. P wave duration, PR, ePR (end of P wave to QRS onset), QT, RR-QT, JT and QRS axis and morphology were putative predictors of atrioventricular (diastolic filling time [DFT]/RR), interventricular mechanical dyssynchrony (IVMD) and left intraventricular mechanical dyssynchrony (left ventricular pre-ejection interval [PEI] and other measures) assessed by transthoracic echocardiography (TTE). Correlations between TTE and electrocardiographic measurements were examined by linear regression.


RESULTS
Statistically significant but relatively weak correlations were found between heart rate (r=-0.5), JT (r=0.3), QT (r=0.3), RR-QT intervals (r=0.5) and DFT/RR, though not with PR and QRS intervals. Weak correlations were found between: (a) QRS (r=0.3) and QT interval (r=0.3) and (b) IVMD > 40 ms; and between (a) ePR (r=-0.2), QRS (r=0.4), QT interval (r=0.3) and (b) LVPEI, though not with other indices of intraventricular dyssynchrony.


CONCLUSIONS
The correlations between electrical and the evaluated mechanical indices of cardiac dyssynchrony were generally weak in heart failure candidates for CRT. These data may help to explain the discordance between electrocardiographic and echocardiographic criteria of ventricular dyssynchrony in predicting the effect of CRT.
Service de cardiologie et maladie vasculaire, CHU de Tours, 37000 Tours, France; LTSI, université Rennes 1, 35000 Rennes, France. Electronic address: albinbehaghel@chu-rennes.fr.
Albin
A
Behaghel
Service de cardiologie et maladie vasculaire, CHU de Tours, 37000 Tours, France.
Anne
A
Brunet-Bernard
Centre d'investigation clinique, CHU de Rennes, 35000 Rennes, France.
Emmanuel
E
Oger
Service de cardiologie et maladie vasculaire, CHU de Tours, 37000 Tours, France; LTSI, université Rennes 1, 35000 Rennes, France.
Raphaël
R
Martins
Service de cardiologie et maladie vasculaire, CHU de Tours, 37000 Tours, France; LTSI, université Rennes 1, 35000 Rennes, France.
Erwan
E
Donal
Service de cardiologie et maladie vasculaire, CHU de Tours, 37000 Tours, France; LTSI, université Rennes 1, 35000 Rennes, France.
Maxime
M
Fournet
Service de cardiologie et maladie vasculaire, CHU de Tours, 37000 Tours, France; LTSI, université Rennes 1, 35000 Rennes, France.
Damien
D
Feneon
Service de cardiologie et maladie vasculaire, CHU de Tours, 37000 Tours, France; LTSI, université Rennes 1, 35000 Rennes, France.
Christophe
C
Leclercq
Service de cardiologie et maladie vasculaire, CHU de Tours, 37000 Tours, France; LTSI, université Rennes 1, 35000 Rennes, France.
Philippe
P
Mabo
Service de cardiologie et maladie vasculaire, CHU de Tours, 37000 Tours, France; LTSI, université Rennes 1, 35000 Rennes, France.
Claude
C
Daubert
D058409:Cardiac Resynchronization Therapy Devices / Q000706:statistics & numerical data*; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006333:Heart Failure / Q000503:physiopathology / Q000628:therapy*; D006339:Heart Rate / Q000502:physiology*; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
Cardiac resynchronization; Corrélations électromécaniques; Electromechanical dyssynchrony; Heart failure; Insuffisance cardiaque; Resynchronisation cardiaque