Summary of treatment options in refractory angina pectoris

TENS: transcutaneous electrical nerve stimulation; SCS: spinal cord stimulation; TMR: transmyocardial laser revascularization; PLR: percutaneous laser revascularization; LSGB: left stellate ganglion blockade.
Strength of evidence is based upon amount of scientific documentation: A: Well-designed, well-conducted, controlled trials (randomized and non-randomized) with statistically significant results that consistently support the recommendations. B: Observational studies or controlled trials with less consistent results to support the guideline recommendations. C: Expert opinion that supports the guideline recommendation because the available scientific evidence did not present consistent results, or controlled trials were lacking.