Preoperative expectations and clinical outcome of transmyocardial laser treatment in patients with angina pectoris

BACKGROUND: The aims of this study were to evaluate the effect of transmyocardial laser treatment on quality of life and to assess the correlation between preoperative expectations and clinical improvement after one year. MATERIAL AND METHODS: 13 patients (median age 56 years) with disabling angina pectoris were subjected to transmyocardial holmium: YAG laser. Quality of life was assessed preoperatively and at three and 12 months by Hospital Anxiety and Depression Scale (HAD), Physical Symptom Distress Index (PSDI) and Life Satisfaction Index (LSI). Expectations were evaluated by Leedham's scale. RESULTS: A significant improvement in Canadian Cardiovascular Society Score (CCS) from 3.4 +/- 0.5 (mean +/- SD) preoperatively to 1.6 +/- 1.0 and 1.7 +/- 0.8 three and 12 months after treatment was observed (p < 0.01). Quality of life (PSDI and LSI) improved. No significant changes in ejection fraction or exercise performance were found. Preoperative expectations were generally high, but did not correlate significantly with improvements in CCS or quality of life. INTERPRETATION: Although no changes in objective parameters were found, the lack of significant correlations between preoperative expectation and subjective clinical improvement indicate that the improvement of angina pectoris only partly can be explained by placebo effects.