Transmyocardial laser revascularization in the patient with unmanageable unstable angina

Background. Transmyocardial laser revascularization (TMR) provides relief f or patients with chronic angina, nonamenable to direct coronary revasculari zation. Unmanageable, unstable angina (UUA) defines a subset of patients wi th refractory angina who are at high risk for myocardial infarction and dea th. Patients were classified in the UUA group when they had been admitted t o the critical care unit with unstable angina for 7 days with three failed attempts at weaning them off intravenous antianginal medications. Methods. Seventy-six treated patients were analyzed to determine if TMR is a viable option for patients with unmanageable unstable angina. These patie nts were compared with 91 routine protocol patients (protocol group [PG]) u ndergoing TMR for chronic angina not amenable to standard revascularization . The procedure was performed through a left thoracotomy without cardiopulm onary bypass. These patients were followed for 12 months after the TMR proc edure. Both unmanageable and chronic angina patients had a high incidence o f at least one prior surgical revascularization (87% and 91%, respectively) . Results. Perioperative mortality(less than or equal to 30 days post-TMR) wa s higher in the UUAG versus PG (16% vs 3%, p = 0.005). Late mortality, up t o 1 year of follow-up, was similar (13% vs 11%, UUAG vs PG; p = 0.83). A ma jority of the adverse events in the UUAG occurred within the first 3 months post-TMR, and patients surviving this interval did well, with reduced angi na of at least two classes occurring in 69%, 82%, and 82% of patients at 3, 6, and 12 months, respectively. The percent improvement in angina class fr om baseline was statistically significant at 3, 6, and 12 months. A compara ble improvement in angina was found in the protocol group of patients. Conclusions. TMR carried a significantly higher risk in unmanageable, unsta ble angina than in patients with chronic angina. In the later follow-up int ervals, however, both groups demonstrated similar and persistent improvemen t in their angina up to 12 months after the procedure. TMR may be considere d in the therapy of patients with unmanageable, unstable angina who otherwi se have no recourse to effective therapy in the control of their disabling angina. (C) 1999 by The Society of Thoracic Surgeons.