PCSK9 inhibitors in the management of hypercholesterolaemia after heart transplantation in the UK, a single centre observational study

We looked to establish if Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor therapy can be safely initiated in heart transplant recipients and effectively reduce target low density lipoprotein (LDL). This prospective audit reviewed heart transplant recipients between 1st June 2019 and 1st November 2022 at Harefield Hospital in London. At baseline all patients must have attempted statin and ezetimibe therapy. All patients who remained with an LDL > 3.5 with very high cardiovascular risk or LDL > 4.0mmol/L with high risk were initiated on alirocumab injection every 2 weeks. Monitoring including biochemical analysis including immunotherapy levels, troponin, brain natriuretic peptides, electrocardiograph and echocardiogram. PCKS9i therapy was tolerated in 9/11 patients with 2 stopping treatment, one due to nausea & vomiting and one due to elevation in creatinine kinase. No adverse effects related to the heart transplant were detected and no significant change in creatinine kinase, liver function or left ventricular ejection fraction were seen. A significant reduction in LDL, total cholesterol, triglycerides was seen with LDL cholesterol reduction of 55% from 4.14 ± 0.47mmol/L at baseline to 1.86 ± 0.89mmol/L at 12 months. Estimated treatment effects constant over time expects to reduce LDL by about 2.19 to 2.77 mmol/L with 95% probability. Total cholesterol is likely to be lowered by 2.22 to 2.91 mmol/L and triglycerides by 0.42 to1.6 mmol/L with the same probability. This audit demonstrates limited safety and efficacy data of PCSK9i therapy in heart transplant recipients with elevated LDL cholesterol.