Intravascular laser therapy of acute myocardial infarction. The efficacy of a new method of treatment, endovascular blood irradiation with He-Ne laser, developed by the authors, was studied in 295 patients with primary acute transmural myocardial infarction (MI). Twenty-four-hour Holter monitoring findings before and after laser irradiation suggested the possibility of preventing sudden death in the acute period of MI owing to the high anti-arrhythmic efficacy of the method with respect to high-grade ventricular arrhythmias. Precodial ECG mapping and serial determination of blood enzyme activities (CPK and MB-CPK) showed that irradiation performed within the first hours of MI development contributed to effective limitation of the infarction area and restricted the spread of the area of myocardial ischemic damage. 