John L. Rink

Correlation of coronary angioscopic to angiographic findings in coronary artery disease

An Olympus ultrathin fiberscope, 1.8 mm outer diameter, was inserted intraluminally into 11 stenoses of the left anterior descending and circumflex coronary arteries in 8 patients at coronary bypass surgery. Intraluminal views were obtained by coupling the angioscope to a color video camera and videotape recorder, and compared with preoperative coronary angiographic findings in right and left anterior oblique views. Atherosclerotic plaque was observed as yellow-white mass attached onto the luminal lining, which may be large enough to virtually obliterate the vascular lumen. Angioscopy provided a topographic view and cross-sectional picture of stenosis not observed by angiography. Single-plane angioscopic cross-sectional stenotic lumens correlated well (r = 0.90, p less than 0.001) with calculated angiographic luminal narrowings. However, with subtotal obstruction, lesion length must be assessed angiographically. Coronary angioscopy can be a useful adjunct to angiography by providing the added dimension of the true cross-sectional view of obstruction.

Laser Treatment of Coronary Artery Disease

Extension of the principle of microwave amplification by stimulated emission of radiation (maser) [1] afforded the development of laser (light amplification by stimulated emission of radiation) from devices that emit energized light within the visible spectrum [2]. Initial medical application of such photoradiation included retinal coagulation [3], tumor ablation [4], dermal surgery [5], and gastric hemostasis [6]. These advances have led to progress in the dissolution of obstructive atherosclerotic vascular disease with laser radiation [7]. In experiments carried out in our laboratories in the late 1970s performing balloon angioplasty in human cadaver coronary arteries [8], we found that balloon catheters could not traverse many subtotal coronary stenoses. Our initial concept of using lasers was to create a large enough channel through the obstructive lesion to allow the passage of a balloon catheter for coronary angioplasty. The application of laser as it has evolved during the past few years into the clinical treatment of coronary artery disease is described in the present report.