Author + information
- Received December 10, 1985
- Revision received March 3, 1986
- Accepted March 26, 1986
- Published online September 1, 1986.
- Richard N.W. Hauer, MD*,1,
- Willem Straks, MD1,
- Cornelius Borst, MD1 and
- Etienne O. Robles De Medina, MD, FACC1
- ↵*Address for reprints: Richard N.W. Hauer, MD, Department of Cardiology, University Hospital Utrecht, Catharijnesingel 101, P. O. Box 16250, 3500 CG Utrecht, The Netherlands.
Electrical catheter ablation of arrhythmogenic sites is now being used for the treatment of ventricular tachycardias. However, the extent and type of the ablation lesion in relation to energy level are controversial and not well known. In 10 beagles, single cathodal shocks of 30 (4 dogs), 80 (2 dogs) or 250 J (4 dogs) were delivered to the endocardial ventricular wall (5 dogs left ventricular, 5 dogs right ventricular). One week after ablation the dogs were killed for histopathologic examination. In the left ventricular wall, ablation lesion volumes calculated from measured extensions in three perpendicular directions were 0.4 and 0.9 cc at 30 J, 1.9 cc at 80 J and 2.8 and 3.4 cc at 250 J; in the right ventricular wall they were 0.4 and 0.5 cc at 30 J, 1.3 cc at 80 J and 2.5 and 4.2 cc at 250 J. In the right ventricular wall all 30 to 250 J lesions were transmural, whereas in the left ventricular wall only 250 J lesions were transmural. AH lesions showed a necrotic area surrounded by granulation tissue with degenerated myofibrils.
Thus, the size of the ablation lesion depends on delivered energy, whereas the pattern of histopathologic change is identical in the 30 to 250 J energy range. These results suggest that with accurate localization of the ar-rhythmogenic site one low energy shock may be successful with less myocardial damage.
- Received December 10, 1985.
- Revision received March 3, 1986.
- Accepted March 26, 1986.
- American College of Cardiology Foundation