Lipoprotein Apheresis in Refractory Angina Study

Overview

The goal of this study is to determine the impact of apheresis on clinical parameters and symptoms of patients with refractory angina and raised Lp(a). The investigators will conduct a prospective, randomised controlled crossover study of 20 patients with refractory angina and raised Lp(a), randomised to undergoing lipoprotein apheresis weekly for three months or sham apheresis weekly for three months with assessment of myocardial perfusion, carotid atherosclerosis, endothelial vascular function, thrombogenesis, exercise capacity, angina symptoms and quality of life at the beginning and end of treatment. Patients will then crossover to the opposite study arm with the protocol repeated. The hypothesis is that the above parameters will be improved by lipoprotein apheresis in patients with raised Lp(a) and Refractory Angina. Investigators will also test for the genotypic presence of apolipoprotein(a) gene (LPA) locus variants (rs10455872 and rs3798220) which are thought to be associated with an increased level of Lp(a) and an increased risk of coronary disease.

Angina which is refractory to conventional medical therapy and revascularisation is challenging to manage. Lipoprotein(a) or Lp(a) is a genetically determined form of LDL-cholesterol, elevation of which is an independent risk factor and predictor of adverse cardiovascular events. Lp(a) is felt to increase cardiovascular risk via its prothrombotic effect and by enhancing intimal lipoprotein deposition. Lipoprotein apheresis is the most effective treatment for raised Lp(a). Lipid lowering agents such as statins have little to no effect on Lp(a) levels.