Linear lesions in heart tissue using diffused laser radiation

Nathaniel M. Fried, Albert C. Lardo, Ronald D. Berger, Hugh Calkins, Henry R. Halperin

Research output: Contribution to journalConference articlepeer-review


Transmural, continuous, and linear lesions may be necessary for successful catheter ablation of cardiac arrythmias such as atrial fibrillation. Laser ablation was studied as an alternative to radiofrequency ablation, which is noted to produce superficial and discontinuous lesions as well as tissue charring and vaporization. Samples of canine myocardium were placed in a saline bath and irradiated with an 1.06-μm Nd:YAG laser operated in either pulsed or continuous mode. For pulsed mode, the laser pulse duration was 10 s with 10 s cooling between pulses. Laser radiation was delivered radially through diffusing optical fiber tips oriented parallel to the endocardial surface. In CW mode, transmural (6-mm-deep), linear (16-mm-long), and continuous lesions were produced using a laser power of 30 W and an irradiation time of 180 s. Peak tissue temperatures measured 51±1 °C at the endocardial surface, 61±6 °C in the mid-myocardium, and 55±6 °C at the epicardial surface. There was no evidence of tissue charring or vaporization. Pulsed laser irradiation produced comparable lesion depths to CW irradiation with more uniform heating of the subsurface myocardium, but at the expense of longer operation times. Further in vivo study of laser ablation is warranted for possible clinical applications.

Original languageEnglish (US)
Pages (from-to)544-551
Number of pages8
JournalProceedings of SPIE - The International Society for Optical Engineering
StatePublished - Jan 1 2000
EventLasers in Surgery: Advanced Characterization, Therapeutics, and Systems X - San Jose, CA, USA
Duration: Jan 22 2000Jan 25 2000

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Linear lesions in heart tissue using diffused laser radiation'. Together they form a unique fingerprint.

Cite this