Ranolazine in refractory and chronic stable angina

Introduction: The current Scottish Intercollegiate Guidelines Network (SIGN) guidelines recommend beta blockers and dihydropiridine calcium channel blockers as first-line agents for refractory angina pectoris. Despite being optimally treated with pharmacotherapy and revascularisation, up to 40% of patients still experience symptoms. Ranolazine, a piperazine derivative, selectively inhibits late sodium currents and is of particular interest as it is currently not recommended routinely by SIGN guidelines and Scottish Medicine Consortium (SMC) but has been prescribed in Tayside, initially through IPTR since 2017 and recently through a Local New Medicine Treatment Protocol and Stable Angina Pathway. Real world experience of ranolazine prescribing in patients with chronic and often refractory angina is not widely reported. We therefore audited its use in Tayside to understand its prescribing pattern within our patient population and assess its effects on angina symptom relief. Methods: Electronic health records and prescribing data between 1st January 2012 and 31st December 2018 were retrospectively analysed. Data on baseline characteristics, prescribing information, past medical history, and angina symptom control were collected. Standard descriptive statistics were used for analysis. Results: 35 patients were identified as suitable for inclusion in the audit. Mean age was 71.4 ± 12.5 years old and 68.6% were male. 23 patients (65.7%) had either a previous percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG). The most common reason for ranolazine prescription was refractory angina (74.3%) with 375 mg BD being the most common dose. Prescription of guideline-recommended anti anginals was high with 80% of patients being on a beta blocker and a nitrate prior to commencing ranolazine. Encouragingly, 27 patients (77.1%) reported an improvement in Canadian Cardiovascular Society (CCS) angina class and the rate of non-responders was 22.9%. No adverse effects leading to discontinuation of ranolazine was found. Conclusion: Ranolazine may play a role as an additional anti anginal agent with reasonable achievement of symptom control in patients who have refractory angina despite the use of other guideline-recommended anti anginal agents