1993 Volume 14 Issue Supplement Pages 437-440
Recently, clinical study on percutaneous translumial laser coronary angioplasty (PTLCA) has been started and cases of vascular perforation were seen among the reports pointing out necessities of detailed preoperative diagnosis of arteriosclerosis and monitoring of intraoperative state of ablation. we applied a newly developed coronary endoscopic fluorescence spectrum analyser (exciting light: mercury-xenon lamp filtered light 405nm wavelength) to clinical uses and examined its usefulness together with the result obtained in the heart of a dead body.
First of all, as a basic study, we analyzed spectra using non-arteriosclerotic and arteriosclerotic rabbits. after excision of the aorta out of the respective rabbits, autofluorescence spectrum was determined in the arteriosclerotic and normal regions using a fluorescence spectrum analyser. then, the same arterial specimens were incubated in a doxycyclin solution for 15 minutes and fluorescence spectrum was measured again from the same regions. Thereafter, the regions where spectrum was measured were examined histologically. Next, 30 sites in the coronary artery of a dead body were classified into normal regions, white atheroma and yellow atheroma and autofluorescence was determined, respectively. Further, these specimens were processed with doxycycline similarly as in the case of rabbits and fluorescence was measured again for histological examination. In 30 cases of ischemic heart diseases with 90% or more coronary stenosis, coronary endoscopy was performed according to the double guiding catheter method and analyzed the spectrum in the observation sites. In 10 cases out of these, 200mg doxycycline were administered after observation by coronary endoscopy and similar measurements were made. In the result, autofluorescence of 540nm peak was obtained in the tunica media in the healthy regions of the rabbits and coronary artery of a dead body while the height of this wave was reduced in the arteriosclerotic regions. After doxycycline processing, the spectrum peak shifted from 540 to 560nm and augumented in the arteriosclerotic regions. In clinical applications, a flurorescence spectrum was clearly measurable in coronary arteriosclerotic lesions. In the cases given doxycycline, a unique spectrum with its peak at 560nm was observed in the arteriosclerotic lesion.In the present study, it was confirmed clinically that doxycyclin flurorescence was measurable as a photosensitizer. When this method is employed as an intraoperative monitoring during PTLCA, the doxycyclin peak height is considered to indicate the depth of ablation and is expected to serve as a meansto prevent vascular perforation.
