Myocardial performance after transmyocardial revascularization with CO(2)laser. A dobutamine stress echocardiographic study.

Aims: Transmyocardial laser revascularization is a treatment for patients with severe angina pectoris not eligible for conventional revascularization. The effects on myocardial function and reversible ischaemia have not been clarified. Methods and Results: One hundred patients with refractory angina not eligible for conventional revascularization were randomized 1:1 to receive continued optimal medical treatment or transmyocardial revascularization with CO2 laser in addition to medical treatment. Dobutamine stress echocardiography examinations were performed at baseline and at 3 and 12 months after randomization. The effects of transmyocardial revascularization on myocardial function and reversible ischaemia were assessed by visual interpretation of cineloops at rest and during stress in a 16-segment model. After transmyocardial revascularization resting left ventricular wall motion abnormalities increased ( P <0·01), whereas wall motion during dobutamine stimulation remained unchanged. The number of probably non-viable segments increased ( P <0·01) with a corresponding decrease in the number of ischaemic segments. Fewer patients had the dobutamine infusion discontinued because of chest pain after transmyocardial revascularization with laser, but the chest pain threshold did not increase significantly. Conclusion: Following transmyocardial revascularization, resting wall motion abnormalities worsened, wall motion abnormalities during dobutamine stimulation remained unchanged and the number of probably non-viable segments increased.