title: Transmyocardial revascularization with a carbon dioxide laser in patients with end-stage coronary artery disease.
abstract: BACKGROUND
  The construction of subendocardial channels to perfuse ischemic areas of the myocardium has been investigated since the 1950s. We assessed the safety and efficacy of transmyocardial revascularization with a carbon dioxide laser in patients with refractory angina and left ventricular free-wall ischemia that was not amenable to direct coronary revascularization.
  
  
  METHODS
  In a prospective, controlled, multicenter trial, we randomly assigned 91 patients to undergo transmyocardial revascularization and 101 patients to receive continued medical treatment. The severity of angina (according to the Canadian Cardiovascular Society [CCS] classification), quality of life, and cardiac perfusion (as assessed by thallium-201 scanning) were evaluated at base line and 3, 6, and 12 months after randomization.
  
  
  RESULTS
  At 12 months, angina had improved by at least two CCS classes in 72 percent of the patients assigned to transmyocardial revascularization, as compared with 13 percent of the patients assigned to medical treatment who continued medical treatment (P<0.001). Patients in the transmyocardial-revascularization group also had a significantly improved quality of life as compared with the medical-treatment group. Myocardial perfusion improved by 20 percent in the transmyocardial-revascularization group and worsened by 27 percent in the medical-treatment group (P=0.002). In the first year of follow-up, 2 percent of patients assigned to undergo transmyocardial revascularization were hospitalized because of unstable angina, as compared with 69 percent of patients assigned to medical treatment (P<0.001). The perioperative mortality rate associated with transmyocardial revascularization was 3 percent. The rate of survival at 12 months was 85 percent in the transmyocardial-revascularization group and 79 percent in the medical-treatment group (P=0.50).
  
  
  CONCLUSIONS
  In patients with angina refractory to medical treatment and coronary artery disease that precluded coronary-artery bypass surgery or percutaneous transluminal coronary angioplasty, transmyocardial revascularization improved cardiac perfusion and clinical status over a 12-month period.
authors.affiliation: Department of Cardiovascular Surgery and Research, Texas Heart Institute, Houston 77225-0345, USA.
authors.forename: O H
authors.initials: OH
authors.lastname: Frazier
authors.forename: R J
authors.initials: RJ
authors.lastname: March
authors.forename: K A
authors.initials: KA
authors.lastname: Horvath
mesh_terms: D000368:Aged; D000787:Angina Pectoris / Q000145:classification / Q000188:drug therapy / Q000401:mortality / Q000601:surgery*; D003326:Coronary Circulation; D018592:Cross-Over Studies; D018572:Disease-Free Survival; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D053685:Laser Therapy; D008297:Male; D008875:Middle Aged; D009204:Myocardial Revascularization / Q000379:methods*; D011183:Postoperative Complications / Q000401:mortality; D011446:Prospective Studies; D011788:Quality of Life; D012720:Severity of Illness Index; D015996:Survival Rate; D015899:Tomography, Emission-Computed, Single-Photon