Transmyocardial laser revascularization for inoperable coronary artery disease

Interest in transmyocardial laser revascularization for the treatment of otherwise inoperable coronary artery disease has increased rather dramatically in recent years. The results of several industrially sponsored clinical series have been reported recently, all with significant improvement in angina pectoris that appears both rapid and sustained. In most instances, an associated improvement in exercise tolerance has been reported. Improvement in regional myocardial perfusion has been proclaimed, although it is less consistent and less complete than symptom relief. The mechanisms whereby this clinical effect is achieved remain unknown. Histologic analysis of autopsy material has yielded somewhat conflicting results regarding the persistent patency of laser-created channels. The results of laboratory investigations of this therapy have been equally inconsistent. Despite our ignorance regarding the mechanism of angina relief, clinical experience continues to grow. In addition to the CO2 laser energy source used in early studies, trials of alternative devices using holmium:yttrium-aluminum-garnet and eximer lasers are underway. The latter two employ fiberoptic technology and are currently under development for endovascular approaches.