Short- and intermediate-term clinical outcomes from direct myocardial laser revascularization guided by biosense left ventricular electromechanical mapping.

BACKGROUND

Direct myocardial revascularization (DMR) has been examined as an alternative treatment for patients with chronic refractory myocardial ischemic syndromes who are not candidates for conventional coronary revascularization. Methods and Results-We used left ventricular electromagnetic guidance in 77 patients with chronic refractory angina (56 men, mean age 61+/-11 years, ejection fraction 0.48+/-0.11) to perform percutaneous DMR with an Ho:YAG laser at 2 J/pulse. Procedural success (laser channels placed in prespecified target zones) was achieved in 76 of 77 patients with an average of 26+/-10 channels (range 11 to 50 channels). The rate of major in-hospital cardiac adverse events was 2.6%, with no deaths or emergency operations, 1 patient with postprocedural pericardiocentesis, and 1 patient with minor embolic stroke. The rate of out-of-hospital adverse cardiac events (up to 6 months) was 2.6%, with 1 patient with myocardial infarction and 1 patient with stroke. Exercise duration after DMR increased from 387+/-179 to 454+/-166 seconds at 1 month and to 479+/-161 seconds at 6 months (P=0.0001). The time to onset of angina increased from 293+/-167 to 377+/-176 seconds at 1 month and to 414+/-169 seconds at 6 months (P=0.0001). Importantly, the time to ST-segment depression (>/=1 mm) also increased from 327+/-178 to 400+/-172 seconds at 1 month and to 436+/-175 seconds at 6 months (P=0.001). Angina (Canadian Cardiovascular Society classification) improved from 3.3+/-0.5 to 2.0+/-1.2 at 6 months (P<0.001). Nuclear perfusion imaging studies with a dual-isotope technique, however, showed no significant improvements at 1 or 6 months.

CONCLUSIONS

Percutaneous DMR guided by left ventricular mapping is feasible and safe and reveals improved angina and prolonged exercise duration for up to a 6-month follow-up.