Transmyocardial laser revascularization (TMLR) ith an 850-W CO2 laser involves driling 1-mm channels into a beating heart after left thoracotomy. Clotting acutely occludes tthe channels on the subepicardiam (Sep); in the long term, camerosinusoidal connections improve subendocardial (Sen) PERFUSION.

We treated 21 consecutive patients (pts) (mean age 63 yr, 3 women) who had hibernating myocardium or reduced coronary flow reserve by positron emission tomography (PET) and low-dose dobutamine echocardiography (DE). All pts had distal difuse coronary artery disease refractory to antionginal therapy; 4 had unstable angina (mean angina class (AC) =3.76), and 14 had resting LVEF less than 50%. Of 5 (24%) pts who died postoperatively, 4 (80%) had mitral valve regurgitation and CHF preoperatively (p less than 0.03). Postmortem microscopy in 1 pt revealed multiple patent, endotheliumlined neochannels connected to the native sinusoidal vascularature. The mean AC was 2.5 at 3 mo (n=11 pts, p less than 0.005) and 1.6 at 6 mo (n=8 pts, p less than 0.001). At 3 mo, mean SEn/SEp perfusion ratio on PET had increased in lased anterior and lateral regions but decreased in nonlased septal regions (n=10 pts, p less than 0.05); on DE (n=7 PTS), the perentage of normokinetic segments (15-segment analysis) had increased from 51% at baseline to 64% (p less than 0.05). These results suggest that, at 3mo, TMLR improves clinical status and produces objective benefits in pts without CHF.