Abstract 19420: Epicardial Paracoronary Chemical Ablations Using Endocardial Approach Preserve Coronary Patency
Background: Epicardial ablations are often neccesary to treat ventricular tachycardia (VT). However, this procedure carries significant risk of damage to coronary vessels. We hypothesized that paracoronary epicardial ablations can be performed safely using intra-myocardial injection of alcohol from the endocardial approach.
Methods: 5 swines underwent 3D rotational angiography guided intra-myocardial injection of 1 cc of ethanol at a depth of 5 mm into the myocardium. Lesions were placed at 1-3 locations under the LAD. The animals were survived for 3 days and then sacrificed and the myocardium stained with TTC. Hearts were excised and sectioned for lesion analysis and for histological evaluation.
Results: Injections resulted in lesions that engulfed the coronary vessels, but by angiography and histology did not cause coronary stenosis. In 5/5 (100%) animals the lesions extended to the epicardial surface and were not transmural. Average lesion volume was 325.4 ± 73.5 mm3 and average epicardial scar area was 48.3 ± 23.9 mm2. Injections caused transient ST and blood pressure (BP) changes that return to baseline with a mean time to BP normalization of 159 ± 74 sec. Histological analysis demonstrated disruption of the paracoronary myocardium and the coronary tunica adventitia as well as partial disruption of the tunica media. There were no visible changes in the tunica intima.
Conclusions: Paracoronary epicardial ablations can be performed safely using injection of alcohol from endocardial approach. This novel approach mitigates many of the risks of epicardial RF ablations and should be considered as an alternative to the current methods. Further studies are warranted to determine the long term efficacy of this method. Figure 1. Injection catheter was placed underneath the LAD (A) and alcohol mixed with contrast was injected. (B) Angiography shows that the arteries were patent post injection. (C) Epicardial view reveals epicardial lesions. (D) section through the LV wall
- © 2012 by American Heart Association, Inc.