Effects of transmyocardial revascularization on myocardial perfusion and systolic function assessed by nuclear and magnetic resonance imaging methods

Objective-There is no obvious explanation, except placebo, to the symptomat ic effect of transmyocardial laser revascularization (TMR) in patients with refractory angina. Whether TMR improves myocardial perfusion or relieves s ymptoms without altering cardiac function is not clarified. Methods-One hundred patients with refractory angina were randomized 1:1 to TMR (CO2 laser) and medical treatment, or medical treatment alone. Techneti um 99m (Tc-99m)-tetrofosmin myocardial perfusion tomography (SPECT), quanti tative myocardial perfusion gated SPECT (QGSPECT), technetium 99m (Tc-99m) multiple gated acquisition radionuclide ventriculografi (MUGA) and cine-mag netic resonance imaging (cine-MRI) were performed at baseline and after 3 a nd 12 months. Results-Following TM:R, a slight reduction in left ventricular ejection fra ction (LVEF) (p < 0.05) was observed (MUGA and QGSPECT) compared to baselin e. Inclusion of incomplete studies (QGSPECT) revealed a significant reducti on in LVEF and increase in left ventricular end-diastolic volume (LVEDV) (p < 0.05) compared to a control group. Otherwise, no between-group compariso ns showed statistically significant differences. Conclusion-TMR did not improve myocardial perfusion, but led to a reduction in LVEF and increase in LVEDV, however not significantly different from th e control group.