Dynamic Electrophysiological Changes after Ethanol Ablation for Ventricular Septum: Insights from a Septal Pacing Lead

Figures

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  Figure 1. Fluoroscopic view of ventricular pacing lead and left ventriculography. Left ventriculography showing the anatomical relationship between a pacing lead and interventricular septal hypertrophy (left anterior oblique 30°, cranial 30° projection). The pacing lead was in close proximity to the area of septal hypertrophy.

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  Figure 2. Injection of ice water and carbon dioxide. A microcatheter has been passed through a left anterior descending coronary artery and inserted into the septal branch. When contrast was injected from the tip of the microcatheter, the distal portion of the septum became stained with contrast. The staining was close to the pacing lead. After injection of ice water and carbon dioxide into the septal branch, no pacing failure occurred. Ao = aorta; LA = left atrium; LV= left ventricle.

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  Figure 3. Time course of pacemaker parameters. Temporal changes in pacing parameters after ethanol septal ablation. Lead impedance (A), sensing amplitude (B), and pacing threshold (C) measured from the ventricular pacing lead. The table above shows the trends for each parameter, and the graph below illustrates these trends. Immediately after ethanol injection (1 hour), sensing amplitude markedly decreased, indicating acute myocardial injury. Pacing threshold gradually increased and peaked on day 4, while lead impedance showed a delayed peak on day 5. All parameters subsequently stabilized and remained unchanged between 8 days and 1 year.