Direct visualization of atherosclerosis in small coronary arteries using the epifluorescence stereoscope.
OBJECTIVE
To visualize specifically at the beating heart surface atherosclerosis in small coronary arteries using the photosensitiser, mono-L-aspartyl chlorin e6 (NPe6).


METHODS
Cholesterol-fed atherosclerotic rabbits were injected intravenously with 2.0 mg/kg of NPe6. Atherosclerosis was visualized by allowing NPe6 to accumulate in atheromatous plaques, and then used as a potent fluoroprobe to illuminate atherosclerotic coronary arteries upon excitation by light. An epifluorescence stereoscope system was used to visualize atherosclerosis in small coronary arteries.


RESULTS
Although it was unable to specify the parts of the coronary arteries which had atherosclerotic changes under room light with the naked eye, several brightly illuminated branching small coronary arteries were observed clearly against the dark heart surface through the epifluorescence stereoscope, as an exciting mercury blue light beam was used to irradiate the beating heart. A fluorescence micrograph of the coronary artery, at which orange-red fluorescence was seen through the epifluorescence stereoscope, showed that the atheromatous plaques emitted orange-red fluorescence.


CONCLUSIONS
The presence and extent of small coronary atherosclerosis were demonstrated in the beating heart. Such information may help assess the clinical significance of atherosclerosis in small coronary arteries.
Hayashi
J
J
Department of Medicine and Gerontology, School of Medicine, Kyorin University, Tokyo, Japan.
Saito
T
T
Sato
H
H
Kuroiwa
Y
Y
Aizawa
K
K
D000818:Animals; D003324:Coronary Artery Disease / Q000473:pathology*; D003331:Coronary Vessels / Q000473:pathology*; D005260:Female; D008856:Microscopy, Fluorescence; D011166:Porphyrins; D011817:Rabbits
D011166:Porphyrins; C053434:Talaporfin