Why Some Patients Undergoing Lipoprotein Apheresis Therapy Develop New Cardiovascular Events?

State of the Art: Lipoproteinapherese

Lipoprotein apheresis (LA) is usually a last resort in cardiovascular high-risk patients in the context of secondary prevention after lifestyle measures and maximal pharmacotherapy have failed to prevent the occurrence of new atherosclerotic cardiovascular events (ASCVDE) or to achieve the internationally accepted target values for LDL cholesterol (LDL-C). Patients with homozygous familial hypercholesterolemia (hoFH), in whom myocardial infarctions can occur even in children < 10 years of age without adequate therapy, often owe their survival to LA (used here in primary prevention). Severe hypercholesterolemia (HCH) can often be well controlled with modern potent lipid-lowering agents, including PCSK9 approaches, so that the need for LA has decreased here over the years. In contrast, the number of patients in whom elevation of lipoprotein(a) (Lp(a)) is relevant to atherogenesis is increasing in applications to the apheresis committees of the associations of panel physicians (KV). For this indication, LA is currently the only therapeutic procedure approved by the Federal Joint Committee (G-BA). LA significantly reduces the new occurrence of ASCVDE (comparison with the situation before the start of LA), especially in Lp(a) patients. There are convincing observational studies and a German LA Registry with now 10-year data, but there is no randomized controlled trial. This had been requested by the G-BA in 2008, and a corresponding concept was designed but not accepted by the ethics committee. In addition to the highly effective reduction of atherogenic lipoproteins, many discussed pleiotropic effects of LA itself, the medical rounds and motivating discussions also with the nursing staff, which take place within the weekly LA, certainly contribute to the success of the therapy (steady adjustment of all cardiovascular risk factors, lifestyle measures including smoking cessation, adherence of medication intake). This review article summarizes and discusses the study situation, clinical practical experience as well as the future of LA against the background of the currently rapid development of new pharmacotherapies.

[Lipoprotein apheresis : State of the art and case report of the longest HELP treatment worldwide]

Lipoprotein apheresis is an extracorporeal procedure for the treatment of patients with homozygous familial hypercholesterolemia, patients with severe treatment-resistant hypercholesterolemia and patients with lipoprotein(a) hypercholesterolemia, who show progressive atherosclerotic cardiovascular disease despite optimal treatment. This article reports on the historical developments of the procedures, the most frequently used methods for apheresis as well as the data situation on efficacy and tolerability. Randomized prospective studies on clinical outcomes are not available. Furthermore, the article reports on a patient with homozygous familial hypercholesterolemia and 34 years of treatment with heparin-induced extracorporeal low-density lipoprotein (LDL) precipitation (HELP) apheresis, the longest treatment of this kind worldwide. A second patient with combined heterozygous familial hypercholesterolemia and 31 years of liposorber and HELP apheresis is also described. The observational studies and the case reports demonstrate the safety and long-term tolerability of the procedure.

Modern Approaches to Lower Lipoprotein(a) Concentrations and Consequences for Cardiovascular Diseases

Lipoprotein(a) (Lp(a)) is a low density lipoprotein particle that is associated with poor cardiovascular prognosis due to pro-atherogenic, pro-thrombotic, pro-inflammatory and pro-oxidative properties. Traditional lipid-lowering therapy does not provide a sufficient Lp(a) reduction. For PCSK9 inhibitors a small reduction of Lp(a) levels could be shown, which was associated with a reduction in cardiovascular events, independently of the effect on LDL cholesterol. Another option is inclisiran, for which no outcome data are available yet. Lipoprotein apheresis acutely and in the long run decreases Lp(a) levels and effectively improves cardiovascular prognosis in high-risk patients who cannot be satisfactorily treated with drugs. New drugs inhibiting the synthesis of apolipoprotein(a) (an antisense oligonucleotide (Pelacarsen) and two siRNA drugs) are studied. Unlike LDL-cholesterol, for Lp(a) no target value has been defined up to now. This overview presents data of modern capabilities of cardiovascular risk reduction by lowering Lp(a) level.

LDL Apheresis and Lp (a) Apheresis: A Clinician's Perspective

Purpose of Review

Lipoprotein apheresis is the most effective means of lipid-lowering therapy. However, it’s a semi-invasive, time consuming, and chronic therapy with variable adherence. There are still no specific guideline recommendations for the management of patients on lipid apheresis. The purpose of this review is to discuss the clinical indications and major drawbacks of lipid apheresis in the light of recent evidence.

Recent Findings

Lipoprotein apheresis should be initiated at early ages and performed frequently to receive the expected cardiovascular benefits. However, in clinical practice, most patients experience ineffective apheresis and fail to reach lipid targets. This real-world failure is due to several factors including late diagnosis, delayed referral, and improper frequency of procedures. All these denote that awareness is still low among physicians. Another important factor is the semi-invasive, time consuming nature of the apheresis, leading to high refusal and low adherence rates. Moreover, apheresis decreases quality of life and increases the risk of depression. Mental status is also deteriorated in patients with familial hypercholesterolemia on lipid apheresis. New effective lipid lowering agents are underway with promising cardiovascular results.

Summary

To overcome the drawbacks, a structured approach, including standardized protocols for lipoprotein apheresis with regular cardiovascular follow-up is warranted. New effective lipid lowering agents with documented cardiovascular benefit, should be integrated into the treatment algorithms of patients on lipoprotein apheresis.