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Lipoprotein(a) [Lp(a)] has risen to the level of an accepted cardiovascular disease risk factor, but final proof of causality awaits a randomized trial of Lp(a) lowering. Inhibiting apolipoprotein(a) production in the hepatocyte with ribonucleic acid therapeutics has emerged as an elegant and effective solution to reduce plasma Lp(a) levels. Phase 2 clinical trials have shown that the antisense oligonucleotide pelacarsen reduced mean Lp(a) levels by 80%, allowing 98% of subjects to reach on-treatment levels of <125 nmol/l (∼50 mg/dl). The phase 3 Lp(a)HORIZON (Assessing the Impact of Lipoprotein(a) Lowering With TQJ230 on Major Cardiovascular Events in Patients With CVD) outcomes trial is currently enrolling approximately 7,680 patients with history of myocardial infarction, ischemic stroke, and symptomatic peripheral arterial disease and controlled low-density lipoprotein cholesterol to pelacarsen versus placebo. The co-primary endpoints are major adverse cardiovascular events in subjects with Lp(a) >70 mg/dl and >90 mg/dl, in which either of the two being positive will lead to a successful trial. Additional ribonucleic acid-targeted therapies to lower Lp(a) are in preclinical and clinical development. The testing of the Lp(a) hypothesis will provide proof whether Lp(a)-mediated risk can be abolished by potent Lp(a) lowering., Competing Interests: Funding Support and Author Disclosures Dr.Tsimikas has received research support from the Fondation Leducq and partial support from National Institutes of Health grants HL136275, HL106579, HL108735, HL136098, HL128550, and HL135737. Dr. Tsimikas is an employee of the University of California-San Diego and of Ionis Pharmaceuticals; is a co-inventor and receives royalties from patents owned by the University of California San Diego on diagnostic and therapeutic applications; and is a co-founder and has an equity interest in Oxitope and its affiliates (“Oxitope”) as well as in Kleanthi Diagnostics (“Kleanthi”) (although these relationships have been identified for conflict-of-interest management based on the overall scope of the project and its potential benefit to Oxitope and Kleanthi, the research findings included in this particular publication may not necessarily relate to the interests of Oxitope and Kleanthi; the terms of this arrangement have been reviewed and approved by the University of California San Diego in accordance with its conflict-of-interest policies). Dr. Moriarty has served as an advisor, consultant, and received research support from Regeneron, Sanofi, Amgen, Esperion, Kaneka, Amarin, Stage II Innovations/Renew, Novartis, Ionis, Akcea, FH Foundation, GB Life Sciences, Aegerion, Gemphire, and Pfizer. Dr. Stroes has received fees paid to his institution from Amgen, Akcea, Athera, Sanofi-Regeneron, Esperion, Novo Nordisk, Lily, and Novartis., (Copyright © 2021 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objective: Lipoprotein(a)-hyperlipoproteinemia (Lp(a)-HLP) along with progressive cardiovascular disease has been approved as indication for regular lipoprotein apheresis (LA) in Germany since 2008. We aimed to study the long-term preventive effect of LA and to assess hypothetical clinical correlations of apolipoprotein(a) (apo(a)) by analyzing genotypes and phenotypes., Approach and Results: This prospective observational multicenter study included 170 patients with Lp(a)-HLP and progressive cardiovascular disease (48.9 years median age at diagnosis) despite other cardiovascular risk factors, including low-density lipoprotein cholesterol had maximally been treated (mean baseline low-density lipoprotein cholesterol: measured, 2.56 mmol/L [98.9 mg/dL] and corrected, 1.72 mmol/L [66.3 mg/dL]). Patients were prospectively investigated during a 5-year period about annual incidence rates of cardiovascular events. In addition, apo(a) isoforms and polymorphisms at the apo(a) gene (LPA) were characterized. One hundred fifty-four patients (90.6%) completed 5 years of follow-up. Mean Lp(a) concentration before commencing regular LA was 108.1 mg/dL. This was reduced by a single LA treatment by 68.1% on average. Significant decline of the mean annual cardiovascular event rate was observed from 0.58±0.53 2 years before regular LA to 0.11±0.15 thereafter (P<0.0001); 95.3% of patients expressed at least 1 small apo(a) isoform. Small apo(a) isoform (35.2%) carrying phenotypes were not tagged by single-nucleotide polymorphisms rs10455872 or rs3798220., Conclusions: Results of 5 years of prospective follow-up confirm that LA has a lasting effect on prevention of cardiovascular events in patients with Lp(a)-HLP. Patients clinically selected by progressive cardiovascular disease were characterized by a highly frequent expression of small apo(a) isoforms. Only Lp(a) concentration seemed to comprehensively reflect Lp(a)-associated cardiovascular risk, however., (© 2016 American Heart Association, Inc.)

Background: Lipoprotein(a) (Lp(a)) hyperlipoproteinemia is a major risk factor for cardiovascular disease, which is not affected by treatment of other cardiovascular risk factors. This study sought to assess the effect of chronic lipoprotein apheresis (LA) on the incidence of cardiovascular events in patients with progressive cardiovascular disease receiving maximally tolerated lipid-lowering treatment., Methods and Results: In a prospective observational multicenter study, 170 patients were investigated who commenced LA because of Lp(a)-hyperlipoproteinemia and progressive cardiovascular disease. Patients were characterized regarding plasma lipid status, lipid-lowering drug treatment, and variants at the LPA gene locus. The incidence rates of cardiovascular events 2 years before (y-2 and y-1) and prospectively 2 years during LA treatment (y+1, y+2) were compared. The mean age of patients was 51 years at the first cardiovascular event and 57 years at the first LA. Before LA, mean low-density lipoprotein cholesterol and Lp(a) were 2.56±1.04 mmol·L(-1) (99.0±40.1 mg·dL(-1)) and Lp(a) 3.74±1.63 µmol·L(-1) (104.9±45.7 mg·dL(-1)), respectively. Mean annual rates for major adverse coronary events declined from 0.41 for 2 years before LA to 0.09 for 2 years during LA (P<0.0001). Event rates including all vascular beds declined from 0.61 to 0.16 (P<0.0001). Analysis of single years revealed increasing major adverse coronary event rates from 0.30 to 0.54 (P=0.001) for y-2 to y-1 before LA, decline to 0.14 from y-1 to y+1 (P<0.0001) and to 0.05 from y+1 to y+2 (P=0.014)., Conclusions: In patients with Lp(a)-hyperlipoproteinemia, progressive cardiovascular disease, and maximally tolerated lipid-lowering medication, LA effectively lowered the incidence rate of cardiovascular events., Clinical Trial Registration Url: https://drks-neu.uniklinik-freiburg.de. Unique identifier: DRKS00003119.

Aims: The aims of the study were, first, to critically evaluate lipoprotein(a) [Lp(a)] as a cardiovascular risk factor and, second, to advise on screening for elevated plasma Lp(a), on desirable levels, and on therapeutic strategies., Methods and Results: The robust and specific association between elevated Lp(a) levels and increased cardiovascular disease (CVD)/coronary heart disease (CHD) risk, together with recent genetic findings, indicates that elevated Lp(a), like elevated LDL-cholesterol, is causally related to premature CVD/CHD. The association is continuous without a threshold or dependence on LDL- or non-HDL-cholesterol levels. Mechanistically, elevated Lp(a) levels may either induce a prothrombotic/anti-fibrinolytic effect as apolipoprotein(a) resembles both plasminogen and plasmin but has no fibrinolytic activity, or may accelerate atherosclerosis because, like LDL, the Lp(a) particle is cholesterol-rich, or both. We advise that Lp(a) be measured once, using an isoform-insensitive assay, in subjects at intermediate or high CVD/CHD risk with premature CVD, familial hypercholesterolaemia, a family history of premature CVD and/or elevated Lp(a), recurrent CVD despite statin treatment, ≥3% 10-year risk of fatal CVD according to European guidelines, and/or ≥10% 10-year risk of fatal + non-fatal CHD according to US guidelines. As a secondary priority after LDL-cholesterol reduction, we recommend a desirable level for Lp(a) <80th percentile (less than ∼50 mg/dL). Treatment should primarily be niacin 1-3 g/day, as a meta-analysis of randomized, controlled intervention trials demonstrates reduced CVD by niacin treatment. In extreme cases, LDL-apheresis is efficacious in removing Lp(a)., Conclusion: We recommend screening for elevated Lp(a) in those at intermediate or high CVD/CHD risk, a desirable level <50 mg/dL as a function of global cardiovascular risk, and use of niacin for Lp(a) and CVD/CHD risk reduction.

Objective: To examine whether the vaccination with low density lipoprotein (LDL) antibodies could have a protective effect on rats developed atherosclerosis through the action of atherogenic diet., Methods: Four groups of rats (ranged 8 and 14) were treated for 8 weeks (13 January 2007 to 9 March 2007) at the animal house, Faculty of Pharmacy, King Saud University, Riyadh, Saudi Arabia, with normal control diet (NC), normal control diet+LDL-Ab (NC +I), atherogenic diet (AT), and atherogenic diet + LDL-Ab (AT+I). Lipid concentrations and other different parameters were measured in serum., Results: The concentrations of total cholesterol in atherogenic rats treated with LDL-Ab (AT+I) (n=9) were significantly decreased from 5.72 +/- 0.21 mmol/l to 1.81 +/- 0.08 mmol/l (p<0.001). Low density lipoprotein-cholesterol concentrations were also significantly decreased in AT+I group (p<0.001), as it dropped by 73% from 3.06 +/- 0.09 mmol/l to 0.84 +/- 0.04 mmol/l. Phospholipids concentrations were also decreased in AT+I group (p<0.01). The concentrations of both HDL-cholesterol and triacylglycerol were not significantly different from their matched groups., Conclusion: Results of the present study showed that treatment of atherogenic rats with LDL-Ab significantly decreased the serum concentrations of TC and LDL-C. Our findings suggest that immunization with LDL-Ab has a protective effect on artherogenic rats.

Noninvasive tools to quantitate transgene expression directly are a prerequisite for clinical gene therapy. We established a method to determine location, magnitude, and duration of low-density lipoprotein (LDL) receptor (LDLR) transgene expression after adenoviral gene transfer into LDLR-deficient Watanabe hypercholesterolemic rabbits by following tissue uptake of intravenously injected (111)In-labeled LDL using a scintillation camera. Liver-specific tracer uptake was calculated by normalizing the counts measured over the liver to counts measured over the heart that represent the circulating blood pool of the tracer (liver/heart (L/H) ratio). Our results indicate that the optimal time point for transgene imaging is 4 h after the tracer injection. Compared with control virus-injected rabbits, animals treated with the LDLR-expressing adenovirus showed seven-fold higher L/H ratios on day 6 after gene transfer, and had still 4.5-fold higher L/H ratios on day 30. This imaging method might be a useful strategy to obtain reliable data on functional transgene expression in clinical gene therapy trials of familial hypercholesterolemia.

Epidemiologic studies and in vitro experiments indicate that low density lipoprotein (LDL) subtypes differ concerning their atherogenic potential. Small, dense LDL are more atherogenic than large, buoyant LDL. LDL apheresis is a potent therapeutic modality to lower elevated LDL-cholesterol. It is unknown whether such therapy induces a shift in the LDL subtype distribution. In this study we evaluated the influence of LDL apheresis on the LDL subtype distribution in patients with CHD and familial hypercholesterolemia (FH, n = 22), combined hyperlipidemia (CHLP, n = 6), or Lp[a]-hyperlipoproteinemia (Lp[a]-HLP, n = 4) regularly treated by LDL apheresis (immunoadsorption (n = 14), HELP apheresis (n = 8), dextran sulfate adsorption (n = 7), cascade filtration (n = 3)). On the basis of 6 LDL subfractions (d 1.020;-1.057 g/mL) isolated by density gradient ultracentrifugation the LDL-density profile was determined in each patient before and after apheresis. There was a relative increase of LDL-subfractions 1, 2, and 3 (P < 0.01, P < 0. 05, and P < 0.01, respectively) and a concomitant decrease of LDL subfractions 5 and 6 (P < 0.05) after apheresis. Subgroup analysis indicates that the degree of the small, dense LDL reduction was much more prominent in patients with CHLP compared to patients with FH or Lp[a]-HLP, whereas the type of apheresis technique had no effect. The extent of small, dense LDL reduction correlated with the preapheresis concentrations of small, dense LDL and triglycerides but not with the extent of triglyceride reduction.We conclude that LDL apheresis not only decreases LDL mass, but also improves LDL-density profile, particularly in patients with CHLP.

Purpose: The clinical trial data were reviewed on effects of physical activity on obesity-related dyslipoproteinemias (specifically low HDL-cholesterol (HDL-C), elevated triglycerides (TG), and high total and LDL-cholesterol (TC and LDL-C)) in adult men and women., Methods: Effort was made to identify all randomized clinical trials (RCT), with exercise intervention programs of at least 4 months' duration, which had lipoprotein outcomes. Those that had both an exercise only intervention and control groups or both a diet plus exercise and identical diet only intervention groups were reviewed. Tables were developed of baseline characteristics and weight and lipoprotein changes for aerobic exercise trials by body mass index: 1) < 25.0 kg x m(-2), 2) 25.0-29.9 kg x m(2), and 3) > or = 30.0 kg x m(-2)and for studies involving resistance exercise or increased energy expenditure from daily activities versus structured exercise programs., Results: Very few RCT were found that specifically addressed the role of physical activity in preventing or treating obesity-related adverse lipoprotein levels. There was essentially no evidence found in lean or overweight men or women to support a specific role for exercise in improving undesirable lipoprotein levels; however, trial data strongly suggest that the addition of exercise to a hypocaloric, reduced-fat diet improves HDL-C and TG in men and women with generally desirable initial levels and reduces LDL-C in men and women with initially elevated LDL-C levels. The evidence is also reasonably strong that weight loss, including that achieved solely by exercise, improves HDL-C and TG in obese men, without reducing LDL-C, whereas it remains weak for women. There are also virtually no trial data to support a role for resistance exercise or an increase in daily living activities for improving obesity-related lipoproteins., Conclusions: Current evidence from RCT is too limited to determine whether physical activity can raise low HDL-C or lower high TG or LDL-C levels in overweight and obese individuals.

The effect of heparin-induced extracorporal lipid precipitation (HELP) on the activities of paraoxonase (EC 3.1.8.1) and arylesterase (EC 3.1.1.2) was studied in serum of a patient with hyperlipoproteinaemia (A) and of a patient with non-insulin dependent diabetes mellitus and hyperlipoproteinaemia (B). The enzyme activities were measured spectrophotometrically (Tris-HCl buffer, pH 7.4, 37 degrees C) with paraoxon and phenylacetate as substrates of paraoxonase and arylesterase, respectively. Both patients underwent HELP applications once a week over a period of 7 weeks. Over that period no overall change was observed either in enzyme activities or in the lipid and protein content of the sera. However, each HELP session caused an immediate decrease of EDTA-insensitive arylesterase activity (on average 56% in A and 42% in B), while EDTA-sensitive arylesterase remained almost unaltered. Paraoxonase remained unchanged in A, but decreased in B (approximately 60%). Of the atherogenic lipoprotein parameters, the most pronounced decrease was found in VLDL-cholesterol and in triglycerides (on average 45% in A and 32% in B), while the anti-atherogenic HDL-cholesterol decreased < 10%. Possible implications of the effect of HELP on the enzyme activities studied remain to be explained.

This paper focuses on the development and study of multiple population models for multivariate random length data, of the type often encountered in clinical trials. If experimental outcomes per subject consist of multiple measurements of a quantitative variable and the number of these measurements, then a multivariate random length vector is observed. For this type of data, the experimental treatment is likely to affect both the quantitative measurements and the number of these measurements. One example of such data is from the National Heart, Lung and Blood Institute Type II coronary intervention study (Brensike et al. (1982; Controlled Clinical Trials 3, 91-111; 1984, Circulation 69, 313-324)). The outcome data consist of vectors of lesion sizes with lengths determined by the number of underlying lesions assessed from the patients' angiograms, where both the numbers and the lesion sizes depend on patients' overall disease status. We propose models which can realistically describe the relationships between the quantitative variables and the number of responses. The asymptotic covariance of the maximum likelihood estimators is obtained. Data from the Type II study are analyzed using this multiple population model.

Hyperlipoproteinemia is common in patients with renal disease, but increased lipids are only one of several risk factors frequently identified for coronary artery disease. Before treatment options are instituted, renal disease status, current medications, and possible interactions between drugs must be considered. Hypertriglyceridemia is common in patients with renal failure; therapeutic options are influenced by the levels of serum triglycerides and high-density lipoprotein cholesterol. If nonsteroidal drugs improve renal function and decrease proteinuria in patients with renal disease, hyperlipidemia frequently abates. Interactions between drugs are important considerations when lipid-lowering drug treatment is prescribed in recipients of renal transplants.

Lipoprotein(a), or Lp(a), is a lipoprotein having lipid composition similar to that of LDL, but a protein moiety consisting of ApoB 100 linked by disulfide bridge to apo(a), a glycoprotein with structural similarity to plasminogen. Lp(a) can be both atherogenic and thrombogenic. These two actions are likely to be mutually operative, a fact that on a molar basis makes Lp(a) more of a cardiovascular pathogen than LDL.