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Related Experiment Video

Updated: Jul 10, 2026

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

Effect of multisite pacing on ventricular coordination.

C Varma¹, P O'Callaghan, N G Mahon

¹Department of Cardiological Sciences, St George's Hospital Medical School, Cranmer Terrace, London SW17 0RE, UK. cvarma@sghms.ac.uk

Heart (British Cardiac Society)

|March 22, 2002

Summary

Right ventricular pacing improved coordination in heart failure patients with baseline incoordination. However, left ventricular or biventricular pacing may worsen coordination by causing asynchronous contractions.

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Last Updated: Jul 10, 2026

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

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Area of Science:

Cardiology
Cardiac Electrophysiology
Heart Failure Management

Background:

Left ventricular (LV) dysfunction and dyssynchrony are common in heart failure.
Multisite pacing strategies are explored to optimize cardiac function.

Purpose of the Study:

To evaluate the impact of different multisite pacing configurations on left ventricular function and coordination in patients with heart failure and left bundle branch block.

Main Methods:

Prospective observational study involving 18 heart failure patients.
Pacing at right ventricle (RV) apex, RV outflow tract, LV, and simultaneous biventricular sites.
Echocardiography and LV pressure measurements assessed LV function and cycle efficiency.

Main Results:

The optimal pacing site for improved cycle efficiency varied among patients.
Right ventricular pacing significantly improved cycle efficiency in patients with baseline incoordination.
Left ventricular or biventricular pacing induced asynchronous contractions in some patients, potentially worsening coordination.

Conclusions:

Pacing can enhance ventricular coordination in heart failure patients with baseline incoordination.
Careful selection of pacing sites is crucial, as some configurations may lead to asynchronous contractions.
Further research is needed to define the clinical implications of these findings.