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Correlation of extent of left ventricular endocardial unipolar low-voltage zones with ventricular tachycardia in
Deep Chandh Raja1, Jenish Shroff1, Anugrah Nair1
1The Australian National University, Australian Capital Territory, Australia; Canberra Heart Rhythm Centre, Australian Capital Territory, Australia.
Heart Rhythm
|April 18, 2024
Summary
In nonischemic cardiomyopathy, unipolar endocardial electrogram (EGM) low-voltage zones predict ventricular tachycardia (VT). Specific cutoffs for extent and area of these zones demonstrate good diagnostic accuracy for VT risk stratification.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Diagnostics
Background:
- Endocardial electrogram (EGM) characteristics in nonischemic cardiomyopathy (NICM) lack sufficient exploration for prognostic value.
- Understanding these characteristics is crucial for predicting adverse events in NICM patients.
Purpose of the Study:
- To investigate the correlation between bipolar and unipolar EGM parameters and left ventricular ejection fraction (LVEF) in NICM.
- To identify predictors of ventricular tachycardia (VT) in NICM patients using EGM characteristics.
Main Methods:
- Electroanatomic mapping of the left ventricle was performed in 43 NICM patients.
- Bipolar and unipolar EGM characteristics were correlated with LVEF.
- VT predictors were identified by comparing patients with and without VT.
Main Results:
- Unipolar EGM variables, including voltage and low-voltage zone (LVZ) area, showed better correlation with LVEF than bipolar variables.
- Global mean unipolar voltage, extent of unipolar LVZ, and percentage area of unipolar LVZ were significant predictors of VT.
- Extent and percentage area of unipolar LVZ demonstrated high diagnostic accuracy (AUC 0.82-0.83) for VT prediction.
Conclusions:
- Extent and percentage area of unipolar LVZs are significant predictors of VT in NICM.
- Specific cutoffs for unipolar LVZ extent (>3 segments) and area (>33%) offer good diagnostic accuracy for VT association.
Keywords:
Bipolar voltageElectroanatomic mappingLow-voltage zoneNonischemic cardiomyopathyUnipolar voltageVentricular tachycardiaMore Related Videos
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