This prospective, double-blind, randomized, sham-controlled trial was designed to control for patient and investigator bias in assessing symptomatic improvement after percutaneous myocardial laser revascularization (PMLR) therapy. Eighty-two patients with stable angina pectoris (class III or IV) not amenable to conventional revascularization and with evidence of reversible ischemia, ejection fraction >25%, and myocardial wall thickness >8 mm were randomized to either PMLR with optimal medical therapy (n
40) or to a sham procedure with optimal medical therapy (n
42). With the exception of 1 laser technician, all patients, investigators, and assessors were blinded to treatment through the 12-month follow-up. The primary end point was restricted to Canadian Cardiovascular Society angina class improvement to limit the number of patients exposed to a sham procedure. Secondary assessments included medication usage, quality of life, exercise testing, ejection fraction, and hospitalizations. The incidence of serious adverse events, as determined by cardiac event-free survival at 12 months, was similar between groups. At 12 months, Canadian Cardiovascular Society angina scores improved by >2 classes in significantly more PMLR-treated patients than sham control patients (35% vs 14%, p
0.04). Angina-specific quality-of-life measures were significantly higher in the PMLR group at each follow-up (p