Cochrane: This review examines the effectiveness and safety of a surgical intervention
using a laser device directly on the heart surface for patients
suffering from angina for whom other interventions are not suitable.
This is an updated version of the original review published in 2009.
Patients with prolonged or recurrent chest pain due to heart disease have different treatment options, such as medication, catheter interventions, or coronary artery surgery. In spite of the optimal use of such treatments, an increasing number of patients progress to advanced disease, becoming less responsive to medical treatment, suffering from more severe symptoms, very limited exercise capacity and poor quality of life. Transmyocardial laser revascularization (TMLR) is a surgical intervention intended to re-establish blood flow in some areas of the heart, using a laser device directly on the heart surface, thereby relieving angina and improving symptoms.
Several studies have been carried out to determine the efficacy and safety of this intervention, but most had important methodological limitations and high risk of performance bias in relation to subjective outcomes such as angina pain. Overall, 43.8% of patients in the group treated with laser had their chest pain improved significantly, compared with 14.8% in the medication group. However, the evaluation of chest pain was performed without blinding (patients and doctors were aware of the intervention) and this may have biased the results. On the other hand, the risk of dying at one year was similar between the groups, but there is an excess risk of early mortality following the intervention in the laser group.
This updated review concludes that there is no evidence of clinical benefits after TMLR, but data on safety suggests that the procedure may pose unacceptable risks. The intervention is becoming obsolete and it is not expected that new research in this field would change this conclusion.
Patients with prolonged or recurrent chest pain due to heart disease have different treatment options, such as medication, catheter interventions, or coronary artery surgery. In spite of the optimal use of such treatments, an increasing number of patients progress to advanced disease, becoming less responsive to medical treatment, suffering from more severe symptoms, very limited exercise capacity and poor quality of life. Transmyocardial laser revascularization (TMLR) is a surgical intervention intended to re-establish blood flow in some areas of the heart, using a laser device directly on the heart surface, thereby relieving angina and improving symptoms.
Several studies have been carried out to determine the efficacy and safety of this intervention, but most had important methodological limitations and high risk of performance bias in relation to subjective outcomes such as angina pain. Overall, 43.8% of patients in the group treated with laser had their chest pain improved significantly, compared with 14.8% in the medication group. However, the evaluation of chest pain was performed without blinding (patients and doctors were aware of the intervention) and this may have biased the results. On the other hand, the risk of dying at one year was similar between the groups, but there is an excess risk of early mortality following the intervention in the laser group.
This updated review concludes that there is no evidence of clinical benefits after TMLR, but data on safety suggests that the procedure may pose unacceptable risks. The intervention is becoming obsolete and it is not expected that new research in this field would change this conclusion.
Authors' conclusions:
This review shows that risks associated with TMLR outweigh the potential clinical benefits. Subjective outcomes are subject to high risk of bias and no differences were found in survival, but a significant increase in postoperative mortality and other safety outcomes suggests that the procedure may pose unacceptable risks.