Author + information
- Received November 26, 1984
- Revision received October 8, 1985
- Accepted October 16, 1985
- Published online March 1, 1986.
- Eugene Downar, MDa,
- Jagdish Butany, MD,
- Anthony Jares and
- Boris P. Stoicheff, PhD
- ↵aAddress for reprints: Eugene Downar, MD, Women's College Hospital, 76 Grenville Street, Toronto, Ontario, Canada M5S 1B2.
A xenon-chlorine excimer laser was used to irradiate normal endocardium of fresh sheep and pig hearts as well as unfixed human endocardial scar. Forty pulses of 370 J and 35 ns each resulted in penetration of up to 12 mm in normal tissue and only 3.5 mm in scarred endocardium. Dosimetry indicated that the volume of vaporized scarred tissue was 1/10th that of normal endocardium (0.19 to 0.40 versus 1.35 to 3.22 mm3/J). Ultrastructurally, there was a sharp demarcation of only 10 μbetween the region of injury and normal myocardium, with little evidence of heat injury. The high power and short duration of these lasers coupled with the lack of a boundary zone of injury suggest that excimers may be an ideal tool for arrhythmia ablation.
- Received November 26, 1984.
- Revision received October 8, 1985.
- Accepted October 16, 1985.
- American College of Cardiology Foundation