Use of magnetic resonance imaging to assess myocardial perfusion after transmyocardial laser revascularization.

Background: Transmyocardial laser revascularization (TMLR) is an alternative treatment modality for patients with refractory angina who are not candidates for conventional surgical or percutaneous revascularization. Clinical studies of TMLR have not shown one-to-one correlation between increased myocardial perfusion and improved clinical status.

Methods: Three patients (51, 53, and 70 years old) with severe, diffuse coronary artery disease not amenable to conventional surgical revascularization and with angina (Canadian Cardiovascular Society [CCS] class 3-4) refractory to maximal medical therapy underwent TMLR with a CO2 laser. Preoperative and postoperative cardiac magnetic resonance imaging (MRI) were performed to assess left ventricular perfusion and wall-motion changes in the laser-treated areas. Postoperative MRIs were performed within 6 months of TMLR and at 12 months. Angina status was assessed with the Seattle Angina Questionnaire.

Results: Postoperative adenosine stress myocardial perfusion imaging with MRI revealed improved overall perfusion and a reduction in subendocardial hypoperfused areas when compared to preoperative images. In all patients, an improvement in CCS class was consistent with an improvement in perfusion.

Conclusions: Cardiac MRI can be used to assess improved subendocardial perfusion after TMLR treatment. In our study, we found that endocardial perfusion was maintained over a 12-month period.