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Related Experiment Video

Updated: May 28, 2026

Simultaneous Brightfield, Fluorescence, and Optical Coherence Tomographic Imaging of Contracting Cardiac Trabeculae Ex Vivo

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Physiological relevance of quantifying segmental contraction synchrony.

Lauren Johnson¹, Bouchra Lamia, Hyung Kook Kim

¹Cardiovascular Systems Laboratory, Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.

Pacing and Clinical Electrophysiology : PACE

|October 25, 2011

Summary

This summary is machine-generated.

A new method, CCSI(seg), quantifies left ventricular (LV) segmental contraction synchrony. This segmental analysis provides better insights into LV contraction patterns and contractility than global measures.

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Area of Science:

Cardiology
Biomedical Engineering
Physiology

Background:

Current left ventricular (LV) synchrony indices primarily use global measures.
A novel method for quantifying LV segmental contraction synchrony has been developed.

Purpose of the Study:

To develop and assess the physiological relevance of a novel method for quantifying LV segmental contraction synchrony.
To compare a new segmental synchrony index with existing global indices and contractility measures.

Main Methods:

Echocardiographic and pressure-volume data were collected from dogs under various pacing modes (RA, RV, CRTa, CRTf).
Cross-correlation-based segmental (CCSI(seg)) and integrated (CCSI(int)) synchrony measures were derived from speckle-tracking radial strain.
Left ventricular contractility was assessed using end-systolic pressure-volume relationship (ESPVR) slope (Ees) and ESPVR area (ESPVR(area)).

Main Results:

Right ventricular (RV) pacing reduced global synchrony (CCSI(int)), an effect improved by cardiac resynchronization therapy apex (CRTa) pacing.
CCSI(seg) identified specific myocardial segments responsible for dyssynchrony and poor resynchronization.
RV pacing decreased LV contractility (ESPVR(area)) and stroke work, with only CRTa improving these parameters.
CCSI(seg) changes strongly correlated with global LV contractility alterations (R²=0.698, P=0.005).

Conclusions:

The CCSI(seg) method offers enhanced insights into left ventricular contraction patterns.
Segmental synchrony analysis provides a better correlation with global LV contractility changes compared to integrated measures.