Refractory angina is a growing challenge for palliative medicine: a systematic review of non-invasive interventions.

Background: Refractory angina can have a significant effect on quality of life. Non-invasive interventions have been suggested but there are few guidelines on management. Our aim was to systematically review all studies that reported non-invasive interventions for refractory angina and report on their effectiveness and safety.

Methods: We performed a literature search of six databases and a grey literature search. Treatments considered first line or second line according to the European Society of Cardiology were excluded, as were interventions that had undergone review within the last 3 years. Design, setting and outcomes were extracted and quality was assessed. A narrative synthesis was undertaken, including an analysis of adverse effects.

Results: 4476 studies were screened, 14 studies were included in our analysis. Interventions were specialist multidisciplinary programmes, transcutaneous electrical nerve stimulation (TENS), perhexiline, medical optimisation, morphine and intranasal alfentanil. The effects of specialist programmes and perhexiline treatment were mixed. Positive effects were reported with TENS, opioids and medical optimisation, with improvements in symptoms, exercise capacity and quality of life. No major adverse effects were noted in any of the treatments.

Conclusion: There are non-invasive treatments for refractory angina that are overlooked by current guidelines. While the quality of these studies varies, positive changes have been reported in symptoms, exercise tolerance and quality of life with few adverse effects. There is a need for further research into these treatments which could be useful within the contexts of cardiology and palliative care.