Excimer laser coronary angioplasty: Initial experience at St. Thomas' Hospital

Abstract

Photochemical ablation of coronary artery atheroma using pulsed xenon-chloride excimer laser has, over the past 18 months produced promising results. Worldwide experience amounts to some 2000 cases.

In the first 6 months following installation of the Dymer 200+ laser (Advanced Interventional Systems, Irvine, California, USA) at St. Thomas' Hospital, 53 procedures have been performed in 49 patients. Of these, 52.8% were ‘high risk’ (triple vessel disease, unstable angina, LV ejection fraction <35%, need to treat sole remaining coronary conduit).

Complications were two in hospital deaths (18 and 48 h post-procedure-3.8%); one ELCA related myocardial infarct (1.9%); two haemorrhage requiring transfusion (3.8%); no emergency bypass graft surgery (0%).

Current indications for the use of laser include: (1) long-segment diffuse disease; (2) proximal or ostial stenoses in coronary artery or graft; (3) restenosis after balloon angioplasty; (4) total occlusions crossed by a guidewire; (5) severe stenoses crossed by guidewire but not balloon; and (6) bifurcation lesions or stenoses compromising an important side-branch.

Potential complications include: arterial perforation; aneurysm formation; peripheral embolization by plaque material; abrupt thrombotic closure; dissection; late sudden occlusion; spasm; and restenosis.

Minor problems at the start of the programme involved: modifications to the machine to meet local laser safety requirements; special gases required for the machine; supply and design of fibre optic catheters; guiding catheters; heparin dose; dissection of the coronary artery (major and minor); and selection of patients.