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Ventriculo-arterial (VA) coupling and fQRS as new selection criteria for primary prevention ICD placement
Nathan Engstrom1,2, Hayley L Letson1, Kevin Ng3
1Heart, Sepsis and Trauma Research Laboratory, College of Medicine & Dentistry, James Cook University, 1 James Cook Drive, Townsville, QLD, 4811, Australia.
Insights
Left ventricular ejection fraction (LVEF) is insufficient for identifying heart failure patients who benefit from implantable cardioverter defibrillators (ICDs). Ventriculo-arterial coupling and fragmented QRS (fQRS) may improve risk stratification for sudden cardiac death.
Area of Science:
- Cardiology
- Biomedical Engineering
- Electrophysiology
Background:
- Left ventricular ejection fraction (LVEF < 35%) is a primary criterion for implantable cardioverter defibrillator (ICD) eligibility in heart failure (HF).
- LVEF is an inadequate predictor of sudden cardiac death (SCD) and excludes many HF patients with preserved or mildly reduced LVEF.
- Current international guidelines for primary prophylactic ICD therapy are insufficient for comprehensive risk stratification.
Purpose of the Study:
- To investigate ventriculo-arterial (VA) coupling and fragmented QRS (fQRS) as improved markers for risk stratification in HF patients.
- To enhance patient selection for ICD therapy, particularly for those with varying LVEF and risk of SCD.
- To advance personalized medicine approaches for HF management and SCD prevention.
Main Methods:
- Utilizing VA coupling to assess cardiac and aortic mechanics.
- Analyzing fragmented QRS (fQRS) morphologies to predict arrhythmogenic substrate.
- Correlating these parameters with patient functional capacity and predisposition to lethal arrhythmias.
Main Results:
- Hypothesize that VA coupling and fQRS can better stratify HF patients for ICD benefit than LVEF alone.
- Suggests that HF patients with low physiological reserve may not benefit from ICDs, while those with higher reserves and arrhythmogenic substrate may.
- Proposes a novel approach to identify patients at high risk for SCD.
Conclusions:
- Ventriculo-arterial coupling and fragmented QRS offer a promising alternative to LVEF for optimizing ICD therapy in heart failure.
- This combined approach has the potential to expand eligibility for ICDs to a broader HF population (both low and high LVEF).
- Integrating VA coupling and fQRS can lead to more personalized and effective strategies for preventing sudden cardiac death in heart failure patients.
Abstract:
For decades, left ventricular ejection fraction (LVEF < 35%) has been a mainstay for identifying heart failure (HF) patients most likely to benefit from an implantable cardioverter defibrillator (ICD). However, LVEF is a poor predictor of sudden cardiac death (SCD) and ignores 50% of HF patients with mildly reduced and preserved LVEF. The current international guidelines for primary prophylaxis ICD therapy are inadequate. Instead of LVEF, which is not a good measure of LV contractility or hemodynamic characterization, we hypothesize ventriculo-arterial (VA) coupling combined with fragmented QRS (fQRS) will improve risk stratification and patient suitability for an ICD. Quantifying cardiac and aortic mechanics, and predicting active arrhythmogenic substrate, from varying fQRS morphologies, may help to stratify ischemic and non-ischemic patients with different functional capacities and predisposition for lethal arrhythmias. We propose HF patients with a low physiological reserve may not benefit from ICD therapy, whereas those patients with higher reserves and extensive arrhythmogenic substrate may benefit. Our hypothesis combining VA coupling with fQRS changes has the potential to widen HF patient participation (low and high LVEF) and advance personalized medicine for HF patients at high risk of SCD.
