LDL-apheresis: indications and clinical experience in a tertiary cardiac centre

Vascular Access in Therapeutic Apheresis: One Size Does not Fit All

BACKGROUND

Therapeutic apheresis has been used in treating hematological and non-hematological diseases. For a successful procedure, efficient vascular access is required. Presently, peripheral venous access (PVA), central venous catheterization (CVC), implantable ports, and arteriovenous fistulas (AVFs) are used. This review aims to evaluate different type of access and their pros and cons to help physicians determine the best venous access.

METHODS

The electronic search included PubMed and Google Scholar up to Nov. 2020. The Mesh terms were apheresis, peripheral catheterization, central catheterization, and arteriovenous fistula.

RESULTS

A total of 228 studies were found through database searching. Two independent authors reviewed the articles using their titles and abstracts; 88 articles were selected and the full text was reviewed. Finally, 25 were included. The inclusion criteria were studies incorporating patients with any indication for apheresis.

CONCLUSION

PVA has been promoted in recent years in many centers across the United States to lower the rate of complications associated with vascular access and to make this procedure more accessible. Several factors are involved in selecting appropriate venous access, such as the procedure's duration and frequency, patient's vascular anatomy, and staff's experience. In short-term procedures, temporary vascular access like PVA or CVC is preferred. Permanent vascular access such as AVF, tunneled cuffed central lines, and implantable ports are more beneficial in prolonged treatment period but each patient has to be evaluated individually by apheresis team for the most appropriate method.

Vascular access in lipoprotein apheresis: a retrospective analysis from the UK's largest lipoprotein apheresis centre

INTRODUCTION

Lipoprotein apheresis (LA) has proven to be an effective, safe and life-saving therapy. Vascular access is needed to facilitate this treatment but has recognised complications. Despite consistency in treatment indication and duration there are no guidelines in place. The aim of this study is to characterise vascular access practice at the UK's largest LA centre and forward suggestions for future approaches.

METHODS

A retrospective analysis of vascular access strategies was undertaken in all patients who received LA treatment in the low-density lipoprotein (LDL) Apheresis Unit at Harefield Hospital (Middlesex, UK) from November 2000 to March 2016.

RESULTS

Fifty-three former and current patients underwent 4260 LA treatments. Peripheral vein cannulation represented 79% of initial vascular access strategies with arteriovenous (AV) fistula use accounting for 15%. Last used method of vascular access was peripheral vein cannulation in 57% versus AV fistula in 32%. Total AV fistula failure rate was 37%.

CONCLUSIONS

Peripheral vein cannulation remains the most common method to facilitate LA. Practice trends indicate a move towards AV fistula creation; the favoured approach receiving support from the expert body in this area. AV fistula failure rate is high and of great concern, therefore we suggest the implementation of upper limb ultrasound vascular mapping in all patients who meet treatment eligibility criteria. We encourage close ties between apheresis units and specialist surgical centres to facilitate patient counselling and monitoring. Further prospective data regarding fistula failure is needed in this expanding treatment field.

Lipoprotein(a) in postmenopausal women: assessment of cardiovascular risk and therapeutic options

INTRODUCTION

Lipoprotein(a) [Lp(a)], a low-density lipoprotein (LDL)-like particle, has been independently associated with increased cardiovascular disease (CVD) risk in various populations, such as postmenopausal women. The purpose of this narrative review is to present current data on the role of Lp(a) in augmenting CVD risk in postmenopausal women and focus on the available therapeutic strategies.

METHODS

PubMed was searched for English language publications until November 2015 under the following terms: "therapy" OR "treatment" AND ["lipoprotein (a)" OR "Lp(a)"] AND ("postmenopausal women" OR "menopausal women" OR "menopause").

RESULTS

Only hormone replacement therapy (mainly oral estrogens) and tibolone have been specifically studied in postmenopausal women and can reduce Lp(a) concentrations by up to 44%, although evidence indicating a concomitant reduction in CVD risk associated with Lp(a) is lacking. As alternative treatments for women who cannot, or will not, take hormonal therapies, niacin and the upcoming proprotein convertase subtilisin / kexin type 9 (PCSK-9) inhibitors are effective in reducing Lp(a) concentrations by up to 30%. Statins have minimal or no effect on Lp(a). However, data for these and other promising Lp(a)-lowering therapies including mipomersen, lomitapide, cholesterol-ester-transfer protein inhibitors and eprotirome are derived from studies in the general, mainly high CVD risk, population, and include only subpopulations of postmenopausal women.

CONCLUSIONS

Past, present and emerging therapies can reduce Lp(a) concentrations to a varying extent. Overall, it remains to be proven whether the aforementioned reductions in Lp(a) by these therapeutic options are translated into CVD risk reduction in postmenopausal women.

Systematic Review of Low-Density Lipoprotein Cholesterol Apheresis for the Treatment of Familial Hypercholesterolemia

BACKGROUND

Apheresis is an important treatment for reducing low-density lipoprotein cholesterol (LDL-C) in patients with familial hypercholesterolemia (FH). We systematically reviewed the current literature surrounding LDL-C apheresis for FH.

METHODS AND RESULTS

Electronic databases were searched for publications of LDL-C apheresis in patients with FH. Inclusion criteria include articles in English published in 2000-2013 that provide descriptions of practice patterns, efficacy/effectiveness, and costs related to LDL-C apheresis in patients with FH. Data were stratified by country and FH genotype where possible. Thirty-eight studies met the inclusion criteria: 8 open-label clinical trials, 11 observational studies, 17 reviews/guidelines, and 2 health technology assessments. The prevalence of FH was not well characterized by country, and underdiagnosis was a barrier to FH treatment. Treatment guidelines varied by country, with some guidelines recommending LDL-C apheresis as first-line treatment in patients with homozygous FH and after drug therapy failure in patients with heterozygous FH. Additionally, guidelines typically recommended weekly or biweekly LDL-C apheresis treatments conducted at apheresis centers that may last 2 to >3 hours per session. Studies reported a range for mean LDL-C reduction after apheresis: 57-75% for patients with homozygous FH and 58-63% for patients with heterozygous FH. Calculated annual costs (in US$2015) may reach US$66 374 to US$228 956 per patient for weekly treatment.

CONCLUSIONS

LDL-C apheresis treatment may be necessary for patients with FH when drug therapy is inadequate in reducing LDL-C to target levels. While apheresis reduces LDL-C, high per-session costs and the frequency of guideline-recommended treatment result in substantial annual costs, which are barriers to the optimal treatment of FH.