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In vivo electromechanical assessment of heart failure patients with prolonged QRS duration
- Source :
- Heart Rhythm, 12(6), 1259-1267. Elsevier Science
- Publication Year :
- 2015
- Publisher :
- Elsevier Science, 2015.
-
Abstract
- Combined measurement of electrical activation and mechanical dyssynchrony in heart failure (HF) patients is scarce but may contain important mechanistic and diagnostic clues.The purpose of this study was to characterize the electromechanical (EM) coupling in HF patients with prolonged QRS duration.Ten patients with QRS width120 ms underwent left ventricular (LV) electroanatomic contact mapping using the Noga® XP system (Biosense Webster). Recorded voltages during the cardiac cycle were converted to maps of depolarization time (TD). Electrode positions were tracked and converted into maps of time-to-peak shortening (TPS) using custom-made deformation analysis software. Correlation analysis was performed between the 2 maps to quantify EM coupling. Simulations with the CircAdapt cardiovascular system model were performed to mechanistically unravel the observed relation between TD and TPS.The delay between earliest LV electrical activation and peak shortening differed considerably between patients (TPSmin-TDmin = 360 ± 73 ms). On average, total mechanical dyssynchrony exceeded total electrical activation (ΔTPS = 177 ± 47 ms vs ΔTD = 93 ± 24 ms, P.001), but a large interpatient variability was observed. The TD and TPS maps correlated strongly in all patients (median R = 0.87, P.001). These correlations were similar for regions with unipolar voltages above and below 6mV (Mann-Whitney U test, P = .93). Computer simulations revealed that increased passive myocardial stiffness decreases ΔTPS relative to ΔTD and that lower contractility predominantly increases TPSmin-TDmin.EM coupling in HF patients is maintained, but the relationship between TD and TPS differs strongly between patients. Intra-individual and inter-individual differences may be explained by local and global differences in passive and contractile myocardial properties.
- Subjects :
- medicine.medical_specialty
Magnetic Resonance Spectroscopy
medicine.medical_treatment
Heart Ventricles
Cardiac resynchronization therapy
610 Medicine & health
11171 Cardiocentro Ticino
2705 Cardiology and Cardiovascular Medicine
Contractility
QRS complex
Electrocardiography
2737 Physiology (medical)
Interquartile range
Physiology (medical)
Internal medicine
medicine
Humans
Computer Simulation
Aged
Heart Failure
Cardiac cycle
business.industry
Left bundle branch block
Depolarization
medicine.disease
Myocardial Contraction
Heart failure
Cardiology
Cardiology and Cardiovascular Medicine
business
Subjects
Details
- Language :
- English
- ISSN :
- 15563871 and 15475271
- Volume :
- 12
- Issue :
- 6
- Database :
- OpenAIRE
- Journal :
- Heart Rhythm
- Accession number :
- edsair.doi.dedup.....27b56c6e116aafa6793db695a9ec178f