Conduction System Stimulation to Avoid Left Ventricle Dysfunction
Carlos E González-Matos1,2,3,4, Oriol Rodríguez-Queralto1,3, Fátima Záraket1,3
1Electrophysiology Unit, Cardiology Department, Hospital del Mar, Barcelona, Spain (C.E.G.-M., O.R.-Q., F.Z., J.J., B.C., E.V.).
Circulation. Arrhythmia and Electrophysiology
|January 29, 2024
Summary
Conduction system pacing (CSP) preserves left ventricular function and reduces heart failure hospitalizations compared to right ventricular apical pacing (RVAP) in patients needing frequent ventricular pacing. This study highlights CSP as a potentially superior pacing strategy.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiovascular Research
Background:
- Right ventricular apical pacing (RVAP) is associated with left ventricular dysfunction.
- Conduction system pacing (CSP) has shown promise in reversing left ventricular dysfunction, but data on its preventive effects in patients with preserved ejection fraction are limited.
- There is a need to evaluate CSP's efficacy in preventing left ventricular dysfunction during high-burden ventricular pacing.
Purpose of the Study:
- To compare the effects of CSP versus RVAP on preserving normal ventricular function in patients with a high burden of ventricular pacing.
- To assess the impact of CSP on left ventricular ejection fraction (LVEF) and left ventricular dimensions compared to RVAP.
- To evaluate the rates of heart failure-related hospital admissions between the CSP and RVAP groups.
Main Methods:
- A prospective, randomized, parallel, controlled study involving patients with high-degree atrioventricular block and preserved or mildly deteriorated LVEF (>40%).
- Patients were randomized to receive either conventional RVAP or CSP.
- Outcomes including LVEF, left ventricular end-diastolic diameter, QRS duration, and heart failure admissions were assessed at 6 months.
Main Results:
- Seventy-five patients were randomized; 70 were included in intention-to-treat analysis.
- CSP group showed significantly shorter stimulated QRS duration (124.2±20.2 ms) compared to RVAP (160.4±18.1 ms).
- LVEF significantly decreased in the RVAP group (-5.8%) compared to CSP. RVAP also showed increased left ventricular end-diastolic diameter and higher heart failure admissions (22.6% vs 5.1%) compared to CSP.
Conclusions:
- Conduction system stimulation effectively prevents LVEF deterioration and reduces heart failure-related hospitalizations in patients with normal or mildly impaired LVEF requiring significant ventricular pacing.
- CSP demonstrates a superior profile in maintaining ventricular function and reducing adverse cardiac events compared to RVAP in this patient population.
- These short-term findings warrant confirmation through larger, long-term studies.
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