Atrial ablation with an IRK-151 infrared coagulator.
BACKGROUND
The purpose of this study was to develop a method of atrial ablation. In the IRK-151 infrared coagulator, light from a tungsten-halogen lamp is focused into a quartz rod. The distal exit plane is connected to a tip made of sapphire to allow linear ablation.


METHODS
Thirty-six lesions were created in 9 mongrel dogs. The beating ventricular myocardium was ablated from the epicardium. In each dog, 4 lesions were created by using the following durations of application: 3, 9, 15, and 21 seconds. After the ablation, the myocardium was fixed and stained. A linear lesion on the beating right atrial free wall was created. Before and after the ablation, epicardial plaque-electrode mapping was performed. Three months after ablation, remapping was performed.


RESULTS
The ablated myocardium had well-demarcated necrosis without carbonization or vaporization. The maximum depth was 10.3 +/- 0.8 mm. The conducting pathway was blocked. The block, once made, continued for 3 months.


CONCLUSIONS
The IRK-151 produces well-demarcated lesions that were deep enough for atrial ablation to block the conducting pathway.
Department of Cardiothoracic Surgery, University of Tokyo, Japan.
H
H
Kubota
A
A
Furuse
M
M
Takeshita
Y
Y
Kotsuka
S
S
Takamoto
D000538:Aluminum Silicates; D000818:Animals; D018780:Body Surface Potential Mapping; D002244:Carbon; D017115:Catheter Ablation / Q000295:instrumentation* / Q000379:methods; D004285:Dogs; D004867:Equipment Design; D005500:Follow-Up Studies; D006219:Halogens; D006325:Heart Atria / Q000601:surgery*; D006329:Heart Conduction System / Q000601:surgery; D006352:Heart Ventricles / Q000601:surgery; D007259:Infrared Rays; D008028:Light Coagulation / Q000295:instrumentation* / Q000379:methods; D009206:Myocardium / Q000473:pathology; D009336:Necrosis; D010496:Pericardium / Q000601:surgery; D011791:Quartz; D013997:Time Factors; D014414:Tungsten; D014835:Volatilization
D000538:Aluminum Silicates; D006219:Halogens; D011791:Quartz; D002244:Carbon; D014414:Tungsten