Abstract 17188: Abnormal Local Electrograms in Hibernating Myocardium: a Three-dimensional Electro-anatomic Assessment of Arrhythmogenic Substrate in Patients With Ventricular Tachycardia
Background: Hibernating myocardium has been traditionally thought to have normal electrical properties. This study aimed to assess the local electrogram (EGM) properties in hibernating myocardium.
Methods and Results: Endocardial voltage mapping, metabolic 18FDG-positron emission tomography (PET) scans and perfusion 82Rb, 201Tl or 99mTc scans were performed in 61 ischemic heart disease patients undergoing ventricular tachycardia (VT) ablation. Hibernating areas were identified, which was followed by 3D-PET reconstructions and integration with voltage maps to allow hybrid metabolic-electro-anatomic 3D-assessment of the arrhythmogenic substrate. A total of 303 bipolar voltage recordings were obtained within hibernating myocardium. Local EGMs were categorized into: 1.Normal (sharp biphasic or triphasic spikes, voltage≥3mV, duration0.046); 2.Fractionated (voltage≤0.5mV, duration≥133ms, amplitude/duration ratio<0.005); 3.Isolated potentials (separated from ventricular EGM by isoelectrical segment/low voltage noise20 ms duration). 4.Abnormal. Only 40 of 303 local EGMs (13.2%) were normal. Local EGMs were fractionated in 31 recordings (10.2%), while the remaining 232 (76.6%) were abnormal. Additionally, isolated potentials were observed in 16 recordings (5.3%) in association with abnormal local ventricular EGM caracteritics.
Conclusion: Hibernating myocardium displayed abnormal local EGMs. The findings might underlie the vulnerability to ventricular tachycardia in patients with hypoperfused yet viable hibernating myocardium.
Author Disclosures: M.S. Abdulghani: None. A. Hussien: None. R. Asoglu: None. M. Smith: None. W. Chen: None. R. Vunnam: None. A. Saliaris: None. V. See: None. S. Shorofsky: None. V. Dilsizian: Research Grant; Modest; GE. T. Dickfeld: Research Grant; Modest; Biosense and GE research grant. Consultant/Advisory Board; Modest; Biosense.
- © 2014 by American Heart Association, Inc.