Factors contributing to perforations resulting from laser coronary angioplasty: observations in an intact human postmortem preparation of intraoperative laser coronary angioplasty.

This investigation was designed to assess the potential use of laser coronary angioplasty as an intraoperative adjunct in the surgical treatment of ischemic heart disease. Among 17 postmortem hearts, simulated laser coronary angioplasty was performed at 53 sites with a No. 4F guiding catheter and 240 micron (200 micron core) quartz optical fiber. Perforation complicated laser coronary angioplasty in 33 (62%) of the 53 attempts. Most (n = 29) perforations were thermal; four were purely mechanical. Perforation sites were characterized by extensive calcific deposits (21 of 33 cases [64%] ) and the origin of a side branch (13 of 33 [39%] ). Excessive tortuosity of the extramural coronary artery contributed to arterial perforation in four cases, and precluded attempts to perform laser coronary angioplasty in two other cases. In 19 of the 53 attempts to perform laser coronary angioplasty, a high-frequency two-dimensional echocardiographic probe was used to image the coronary artery during antegrade manipulation of the optical fiber/guiding catheter and laser irradiation of the target arterial stenosis. Although perforation nevertheless occurred in 11 (58%) of 19 sites, only one mechanical perforation resulted; the remaining 10 were thermal. Characteristics of the perforation sites in this group were similar to those noted for the group as a whole. Experience with this model of laser coronary angioplasty indicates that even when access problems associated with percutaneous laser coronary angioplasty are obviated by a simulated intraoperative approach, perforation of the underlying coronary arterial wall continues to represent the "rate-limiting" complication of laser coronary angioplasty. Most perforations occurred in relation to calcific deposits, branch points, and tortuous coronary segments.(ABSTRACT TRUNCATED AT 250 WORDS)