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Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System

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Relationships between paced QRS duration and left cardiac structures and function.

Yangang Su¹, Wenzhi Pan, Xue Gong

¹Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, PR China.

Acta Cardiologica

|May 30, 2009

Summary

This summary is machine-generated.

Paced QRS duration (pQRSd) correlates with cardiac structure and left ventricular ejection fraction (LVEF) in patients with right ventricular pacing. A pQRSd of 180 ms or greater indicates left atrial dilation.

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Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing

Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing

Published on: December 11, 2017

Area of Science:

Cardiology
Cardiac Electrophysiology
Echocardiography

Background:

QRS duration (QRSd) in heart failure patients links to ejection fraction, dyssynchrony, and prognosis.
Relationships between paced QRS duration (pQRSd), cardiac structure/function, and dyssynchrony in chronic right ventricular apical (RVA) pacing are not well understood.

Purpose of the Study:

To investigate the associations between pQRSd and echocardiographic variables in patients with chronic RVA pacing.
To determine if pQRSd predicts cardiac structural changes or ventricular dyssynchrony.

Main Methods:

Seventy patients with DDD(R) pacemakers for atrioventricular block were studied.
Echocardiographic variables including dimensions, LVEF, and dyssynchrony indices (IVMD, Ts-SD) were measured.
Statistical analysis examined correlations between pQRSd and echocardiographic findings.

Main Results:

pQRSd positively correlated with LV dimensions (LVDd, LVDs), left atrial dimension (LAD), and interventricular septum thickness (IVST).
pQRSd negatively correlated with LVEF.
No significant correlation was found between pQRSd and ventricular dyssynchrony indices (IVMD, Ts-SD).
A pQRSd cutoff of 180 ms predicted left atrial dilation with 85.71% sensitivity and 66.67% specificity.

Conclusions:

pQRSd is associated with left cardiac structure and LV systolic function in RVA pacing.
pQRSd exceeding 180 ms is indicative of left atrial dilation.
pQRSd does not correlate with ventricular dyssynchrony in this patient group.