NHLBI Working Group Recommendations to Reduce Lipoprotein(a)-Mediated Risk of Cardiovascular Disease and Aortic Stenosis

Review of recent clinical trials and their impact on the treatment of hypercholesterolemia

PURPOSE OF REVIEW

Cardiovascular disease is the leading cause of death in the United States with incidence expected to increase in the coming decades. Recent years have produced a variety of new and novel therapeutics aimed at reducing the global burden of cardiovascular disease. This review highlights these recent advancements.

RECENT FINDINGS

In addition to more rigorous therapeutic thresholds for traditional LDL lowering agents such as statins, recent studies have developed new pathways of lipid lowering for both typical cardiovascular disease and complex, genetic lipid disorders. This includes inhibition of the cholesterol synthesis enzyme ATP citrate lyase with bempedoic acid, prevention of PCSK9 mRNA translation with inclisiran, inhibition of the lipoprotein lipase inhibitor angiopoetin like 3 protein with evinacumab and the use of anti-sense oligonucleotides to lower lipoprotein(a) levels. Icosapent ethyl, while remaining a topic of debate and controversy, demonstrates efficacy in cardiovascular risk reduction when all available data are examined. Lastly fibrate therapy continues to produce negative results in terms of cardiovascular disease reduction.

SUMMARY

Recent years have yielded breadth and depth to cardiovascular treatments. This expanded armamentarium will allow for more effective and more consistent treatment and prevention of cardiovascular disease.

Lipoprotein(a) and Cardiovascular Disease in Chinese Population: A Beijing Heart Society Expert Scientific Statement

Elevated concentration of lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerotic cardiovascular disease, including coronary artery disease, stroke, peripheral artery disease, and so on. Emerging data suggest that Lp(a) contributes to the increased risk for cardiovascular events even in the setting of effective reduction of plasma low-density lipoprotein cholesterol. Nevertheless, puzzling issues exist covering potential genetic factors, Lp(a) assay, possible individuals for analysis, a cutoff point of increased risk, and clinical interventions. In the Chinese population, Lp(a) exhibited a distinctive prevalence and regulated various cardiovascular diseases in specific ways. Hence, it is valuable to clarify the role of Lp(a) in cardiovascular diseases and explore prevention and control measures for the increase in Lp(a) prevalence in the Chinese population. This Beijing Heart Society experts' scientific statement will present the detailed knowledge concerning Lp(a)-related studies combined with Chinese population observations to provide the key points of reference.

Lipoprotein(a): Evidence for Role as a Causal Risk Factor in Cardiovascular Disease and Emerging Therapies

Lipoprotein(a) (Lp(a)) is an established risk factor for multiple cardiovascular diseases. Several lines of evidence including mechanistic, epidemiologic, and genetic studies support the role of Lp(a) as a causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and aortic stenosis/calcific aortic valve disease (AS/CAVD). Limited therapies currently exist for the management of risk associated with elevated Lp(a), but several targeted therapies are currently in various stages of clinical development. In this review, we detail evidence supporting Lp(a) as a causal risk factor for ASCVD and AS/CAVD, and discuss approaches to managing Lp(a)-associated risk.

Aspirin for Primary Prevention of Cardiovascular Events in Relation to Lipoprotein(a) Genotypes

BACKGROUND

The role of aspirin in reducing lipoprotein(a)-mediated atherothrombotic events in primary prevention is not established.

OBJECTIVES

This study sought to assess whether low-dose aspirin benefits individuals with elevated plasma lipoprotein(a)-associated genotypes in the setting of primary prevention.

METHODS

The study analyzed 12,815 genotyped individuals ≥70 years of age of European ancestry and without prior cardiovascular disease events enrolled in the ASPREE (ASPirin in Reducing Events in the Elderly) randomized controlled trial of 100 mg/d aspirin. We defined lipoprotein(a)-associated genotypes using rs3798220-C carrier status and quintiles of a lipoprotein(a) genomic risk score (LPA-GRS). We tested for interaction between genotypes and aspirin allocation in Cox proportional hazards models for incidence of major adverse cardiovascular events (MACE) and clinically significant bleeding. We also examined associations in the aspirin and placebo arms of the trial separately.

RESULTS

During a median 4.7 years (IQR: 3.6-5.7 years) of follow-up, 435 MACE occurred, with an interaction observed between rs3798220-C and aspirin allocation (P = 0.049). rs3798220-C carrier status was associated with increased MACE risk in the placebo group (HR: 1.90; 95% CI: 1.11-3.24) but not in the aspirin group (HR: 0.54; 95% CI: 0.17-1.70). High LPA-GRS (vs low) was associated with increased MACE risk in the placebo group (HR: 1.70; 95% CI: 1.14-2.55), with risk attenuated in the aspirin group (HR: 1.41; 95% CI: 0.90-2.23), but the interaction was not statistically significant. In all participants, aspirin reduced MACE by 1.7 events per 1,000 person-years and increased clinically significant bleeding by 1.7 events per 1,000 person-years. However, in the rs3798220-C and high LPA-GRS subgroups, aspirin reduced MACE by 11.4 and 3.3 events per 1,000 person-years respectively, without significantly increased bleeding risk.

CONCLUSIONS

Aspirin may benefit older individuals with elevated lipoprotein(a) genotypes in primary prevention.

Elevated Lipoprotein(a) prevalence and association with family history of premature cardiovascular disease in general population with moderate cardiovascular risk and increased LDL cholesterol

Background

Elevated Lipoprotein(a) [Lp(a)] is independently associated with increased cardiovascular disease (CVD) risk. There are discrepancies regarding its epidemiology due to great variability in different populations. This study aimed to evaluate the prevalence of elevated Lp(a) in people with moderate CVD risk and increased LDL-c and to determine the association between family history of premature CVD and elevated Lp(a).

Methods

Random subjects from the CESCAS population-based study of people with moderate CVD risk (Framingham score 10–20 %) and LDL-c ≥ 130 mg/dL, were selected to evaluate Lp(a) by immunoturbidimetry independent of the Isoforms variability. The association between family history of premature CVD and elevated Lp(a) was evaluated using multivariate logistic regression models. Elevated Lp(a) was defined as Lp(a) ​​≥ 125 nmol/L.

Results

Lp(a) was evaluated in 484 samples; men = 39.5 %, median age = 57 years (Q1-Q3: 50–63), mean CVD risk = 14.4 % (SE: 0.2), family history of premature CVD = 11.2 %, Lp(a) median of 21 nmol/L (Q1-Q3: 9–42 nmol/L), high Lp(a) = 6.1 % (95 % CI = 3.8–9.6). Association between family history of premature CVD and elevated Lp(a) in total population: OR 1.31 (95 % CI = 0.4, 4.2) p = 0.642; in subgroup of people with LDL-c ≥ 160 mg%, OR 4.24 (95 % CI = 1.2, 15.1) p = 0.026.

Conclusions

In general population with moderate CVD risk and elevated LDL-c from the Southern Cone of Latin America, less than one over ten people had elevated Lp(a). Family history of premature CVD was significantly associated with the presence of elevated Lp(a) in people with LDL-c ≥ 160 mg/dL.

Integrated identification of key immune related genes and patterns of immune infiltration in calcified aortic valvular disease: A network based meta-analysis

Background: As the most prevalent valvular heart disease, calcific aortic valve disease (CAVD) has become a primary cause of aortic valve stenosis and insufficiency. We aim to illustrate the roles of immune related genes (IRGs) and immune cells infiltration in the occurrence of CAVD.

Methods: Integrative meta-analysis of expression data (INMEX) was adopted to incorporate multiple gene expression datasets of CAVD from Gene Expression Omnibus (GEO) database. By matching the differentially expressed genes (DEGs) to IRGs from “ImmPort” database, differentially expressed immune related genes (DEIRGs) were screened out. We performed enrichment analysis and found that DEIRGs in CAVD were closely related to inflammatory response and immune cells infiltration. We also constructed protein–protein interaction (PPI) network of DEIRGs and identified 5 key DEIRGs in CAVD according to the mixed character calculation results. Moreover, CIBERSORT algorithm was used to explore the profile of infiltrating immune cells in CAVD. Based on Spearman’s rank correlation method, correlation analysis between key DEIRGs and infiltrating immune cells was performed.

Results: A total of 220 DEIRGs were identified and the enrichment analysis of DEIRGs showed that they were significantly enriched in inflammatory responses. PPI network was constructed and PTPN11, GRB2, SYK, PTPN6 and SHC1 were identified as key DEIRGs. Compared with normal aortic valve tissue samples, the proportion of neutrophils, T cells CD4 memory activated and macrophages M0 was elevated in calcified aortic valves tissue samples, as well as reduced infiltration of macrophages M2 and NK cells activated. Furthermore, key DEIRGs identified in the present study, including PTPN11, GRB2, PTPN6, SYK, and SHC1, were all significantly correlated with infiltration of various immune cells.

Conclusion: This meta-analysis suggested that PTPN11, GRB2, PTPN6, SYK, and SHC1 might be key DEIRGs associated with immune cells infiltration, which play a pivotal role in pathogenesis of CAVD.

The Inherited Hypercholesterolemias

Inherited hypercholesterolemias include monogenic and polygenic disorders, which can be very rare (eg, cerebrotendinous xanthomatosis (CTX)) or relatively common (eg, familial combined hyperlipidemia [FCH]). In this review, we discuss familial hypercholesterolemia (FH), FH-mimics (eg, polygenic hypercholesterolemia [PH], FCH, sitosterolemia), and other inherited forms of hypercholesterolemia (eg, hyper-lipoprotein(a) levels [hyper-Lp(a)]). The prevalence, genetics, and management of inherited hypercholesterolemias are described and selected guidelines summarized.

Study design and rationale for the Olpasiran trials of Cardiovascular Events And lipoproteiN(a) reduction-DOSE finding study (OCEAN(a)-DOSE)

BACKGROUND

Data support lipoprotein(a) (Lp[Lp(a)]) being a risk factor for atherosclerotic cardiovascular disease (ASCVD). Olpasiran is a small interfering RNA molecule that markedly reduces Lp(a) production in hepatocytes.

STUDY DESIGN

The Olpasiran trials of Cardiovascular Events And lipoproteiN(a) reduction-DOSE finding study is a multicenter, randomized, double-blind, placebo-controlled dose-finding study in 281 subjects with established ASCVD and Lp(a) > 150 nmol/L. Patients were randomly allocated to one of 4 active subcutaneous doses of olpasiran (10 mg q12 weeks, 75 mg q12 weeks, 225 mg q 12 weeks, or 225 mg q24 weeks) or matched placebo. The primary objective is to evaluate the effects of olpasiran dosed every 12 weeks compared with placebo on the percent change in Lp(a) from baseline at 36 weeks. Enrollment is now complete and follow-up is ongoing.

CONCLUSIONS

OCEAN(a)-DOSE trial is assessing the Lp(a)-lowering efficacy and safety of olpasiran. These data will be used to determine optimal dosing and design for a cardiovascular outcomes trial.

Ancestry, Lipoprotein(a), and Cardiovascular Risk Thresholds: JACC Review Topic of the Week

This study reviews ancestral differences in the genetics of the LPA gene, risk categories of elevated lipoprotein(a) [Lp(a)] as defined by guidelines, ancestry-specific Lp(a) risk, absolute and proportional risk, predictive value of risk thresholds among different ancestries, and differences between laboratory vs clinical accuracy in Lp(a) assays. For clinical decision-making, the preponderance of evidence suggests that the predictive value of Lp(a) does not vary sufficiently to mandate the use of ancestry-specific risk thresholds. This paper interprets the literature on Lp(a) and ancestral risk to support: 1) clinicians on understanding cardiovascular disease risk in different ancestral groups; 2) trialists for the design of clinical trials to ensure adequate ancestral diversity to support broad conclusions of drug effects; 3) regulators in the evaluation of the design and interpretation of results of Lp(a)-lowering trials with different Lp(a) inclusion thresholds; and 4) clinical laboratories to measure Lp(a) by assays that discriminate risk thresholds appropriately.

Use of Lipoprotein(a) in clinical practice: A biomarker whose time has come. A scientific statement from the National Lipid Association

Lipoprotein(a) [Lp(a)] is a well-recognized, independent risk factor for atherosclerotic cardiovascular disease, with elevated levels estimated to be prevalent in 20% of the population. Observational and genetic evidence strongly support a causal relationship between high plasma concentrations of Lp(a) and increased risk of atherosclerotic cardiovascular disease-related events, such as myocardial infarction and stroke, and valvular aortic stenosis. In this scientific statement, we review an array of evidence-based considerations for testing of Lp(a) in clinical practice and the utilization of Lp(a) levels to inform treatment strategies in primary and secondary prevention.

Relation of Serum Lipoprotein(a) Levels to Lipoprotein and Apolipoprotein Profiles and Atherosclerotic Diseases in Japanese Patients with Heterozygous Familial Hypercholesterolemia: Familial Hypercholesterolemia Expert Forum (FAME) Study

AIMS

Lipoprotein(a) [Lp(a)] is a plasma lipoprotein consisting of a low-density lipoprotein (LDL)-like particle with apolipoprotein (Apo)(a), attached via a disulfide bond to Apo B100. Previous studies have shown that high Lp(a) levels are associated with an increased risk of cardiovascular disease in patients with familial hypercholesterolemia (FH). To date, limited data are available as to distribution of Lp(a) in FH and associations of Lp(a) with other lipid profiles and cardiovascular disease. Our study aimed to investigate serum Lp(a) levels in relation to other lipid profiles and clinical conditions in the national largest-ever cohort of Japanese FH patients.

METHODS

This study is a secondary analysis of the Familial Hypercholesterolemia Expert Forum (FAME) Study that includes a Japanese nationwide cohort of FH patients. In 399 patients under treatment for heterozygous FH who had a baseline measurement of serum Lp(a), the present study examined the distribution of Lp(a) levels and associations of Lp(a) with other lipid profiles and clinical conditions including coronary artery disease (CAD).

RESULTS

The distribution of Lp(a) was skewed to the right with a median of 20.8 mg/dL, showing a log-normal distribution. Serum Apo B and Apo E levels were positively associated with Lp(a) levels. Age-adjusted mean of Apo B was 8.77 mg/dL higher and that of Apo E was 0.39 mg/dL higher in the highest category (40+ mg/dL) of Lp(a) than in the lowest category (＜20 mg/dL). LDL-C levels did not show such an association with Lp(a) levels. A tendency towards a positive relationship between Lp(a) and prevalent CAD was observed in men.

CONCLUSION

Our study demonstrated a distribution pattern of Lp(a) in Japanese FH patients and positive relationships of Lp(a) with Apo B and Apo E levels.

Lipid Parameters and Proprotein Convertase Subtilisin/Kexin Type 9 in Healthy Lebanese Adults

Background: High levels of non-HDL cholesterol (non-HDL-C), triglycerides (TG), lipoprotein (a) (Lp(a)), and Proprotein convertase subtilisin/kexin type 9 (PCSK9) as well as low levels of HDL-C are strongly associated with cardiovascular disease (CVD). Our study aims to estimate the prevalence of dyslipidemia and high Lp(a) in the Lebanese population and to study the relationship of these variables with gender, age, body mass index (BMI), and PCSK9. Methods: This cross-sectional study was carried out on a sample of healthy volunteers aged 18 to 65. Blood samples were drawn from volunteers for total cholesterol (TC), HDL-C, TG, PCSK9, and Lp(a) measurements. Non-HDL-C was calculated by subtracting HDL-C from TC. Results: In total, 303 volunteer subjects with an average age of 38.9 years were included in the study. Respectively, 44%, 29.8%, and 44% of men had high non-HDL-C and TG with low HDL-C versus 23.5%, 8%, and 37% in women. Non-HDL-C and TG were significantly higher in men than in women, while the reverse was observed for HDL-C (p < 0.0001 for the three comparisons). Non-HDL-C and TG were significantly correlated with age and BMI (p< 0.0001 for all correlations), while HDL-C was inversely correlated with BMI (p < 0.0001) but not with age. Abnormal Lp(a) levels (≥75 nmol/L) were found in 19.1% of the population, predominantly in women (24.1% versus 13.4% in men, p = 0.004). The median PCSK9 and its interquartile was 300 (254−382) ng/L with no gender difference (p = 0.18). None of the following factors: gender, age, BMI, non-HDL-C, HDL-C, or TG, were independently associated with Lp(a), while PCSK9 was significantly correlated with age, non-HDL-C, and TG in both men and women and inversely correlated with HDL-C in men. Dyslipidemia is very common in the Lebanese population and is associated with age, high BMI, and male sex. Lp(a) is higher in women without any correlation with the lipid profile, whereas PCSK9 is associated with non-HDL-C and TG. Further studies are needed to evaluate the potential role of Lp(a) and PCSK9 in predicting CVD in healthy populations.

Lipoprotein(a) in the Korean Pediatric Population Visiting Local Clinics and Hospitals

In this paper we investigate serum lipoprotein(a), an independent risk factor for cardiovascular disease in the Korean pediatric population. Visiting local clinics and hospitals, 600 lipoprotein(a) tests were performed on 416 Korean children and adolescents (124 boys and 292 girls), with a median age of 11.1 years (interquartile range, IQR, 9.8–13.9). The median lipoprotein(a) level was 21.5 nmol/L (IQR, 8.2–51.7). Among the 416 patients, the 90th percentile value of the initial lipoprotein(a) measurement was 107.8 nmol/L. The proportion of patients with lipoprotein(a) ≥ 100 nmol/L was 11.3%. The lipoprotein(a) level and the proportion of patients with lipoprotein(a) ≥ 100 nmol/L were not significantly different among sex, or age group. Among the 416 patients, 122 (29.3%, 21 boys and 101 girls) underwent at least two follow-up lipoprotein(a) measurements. The median follow-up period was 6.7 months (IQR, 5.5–11.8). The median lipoprotein(a) level across the 122 patients was 25 nmol/L (IQR 10.0–72.0). Among those patients, seven (5.7%) experienced an increase in serum lipoprotein(a) to ≥100 nmol/L during follow-up measurements. Further studies are needed in the Korean pediatric population in order to clarify the clinical significance of this change long-term.

Non-Lipid Effects of PCSK9 Monoclonal Antibodies on Vessel Wall

Elevated low density lipoprotein (LDL) cholesterol and lipoprotein(a) (Lp(a)) levels have an important role in the development and progression of atherosclerosis, followed by cardiovascular events. Besides statins and other lipid-modifying drugs, PCSK9 monoclonal antibodies are known to reduce hyperlipidemia. PCSK9 monoclonal antibodies decrease LDL cholesterol levels through inducing the upregulation of the LDL receptors and moderately decrease Lp(a) levels. In addition, PCSK9 monoclonal antibodies have shown non-lipid effects. PCSK9 monoclonal antibodies reduce platelet aggregation and activation, and increase platelet responsiveness to acetylsalicylic acid. Evolocumab as well as alirocumab decrease an incidence of venous thromboembolism, which is associated with the decrease of Lp(a) values. Besides interweaving in haemostasis, PCSK9 monoclonal antibodies play an important role in reducing the inflammation and improving the endothelial function. The aim of this review is to present the mechanisms of PCSK9 monoclonal antibodies on the aforementioned risk factors.

Elevated lipoprotein(a) as a predictor for coronary events in older men

Elevated circulating lipoprotein (a) [Lp(a)] is associated with an increased risk of first and recurrent cardiovascular events; however, the effect of baseline Lp(a) levels on long-term outcomes in an elderly population is not well understood. The current single-center prospective study evaluated the association of Lp(a) levels with incident acute coronary syndrome to identify populations at risk of future events. Lp(a) concentration was assessed in 755 individuals (mean age of 71.9 years) within the community and followed for up to 8 years (median time to event, 4.5 years; interquartile range, 2.5–6.5 years). Participants with clinically relevant high levels of Lp(a) (>50 mg/dl) had an increased absolute incidence rate of ASC of 2.00 (95% CI, 1.0041) over 8 years (P = 0.04). Moreover, Kaplan-Meier cumulative event analyses demonstrated the risk of ASC increased when compared with patients with low (<30 mg/dl) and elevated (30–50 mg/dl) levels of Lp(a) over 8 years (Gray’s test; P = 0.16). Within analyses adjusted for age and BMI, the hazard ratio was 2.04 (95% CI, 1.0–4.2; P = 0.05) in the high versus low Lp(a) groups. Overall, this study adds support for recent guidelines recommending a one-time measurement of Lp(a) levels in cardiovascular risk assessment to identify subpopulations at risk and underscores the potential utility of this marker even among older individuals at a time when potent Lp(a)-lowering agents are undergoing evaluation for clinical use.

Elevated Lp(a) and course of COVID-19: Is there a relationship?

Background

Lipoprotein (a)–Lp(a) has proinflammatory, prothrombotic and proatherogenic properties and may theoretically influence the course of COVID-19.

Objectives

The aim of the study was to explore whether patients hospitalized due to COVID-19 with Lp(a) ≥30mg/dl may develop a worse course of the disease, increased incidence of thromboembolic complications, intubation and ICU hospitalization or death.

Patients and methods

A retrospective analysis was performed of 124 patients hospitalized due to COVID-19 in the Department of Internal Diseases and Clinical Pharmacology between 29 November 2020 and 15 April 2021. The only exclusion criterion was age≥80 years. Patients were divided into two groups: 1. COVID-19 patients with Lp(a) <30mg/dl regarded as not elevated n = 80; 2. COVID-19 patients with Lp(a) ≥30 regarded as elevated n = 44.

Results

A total of 124 COVID-19 patients were included in the study (66 men and 58 women) with a mean age of 62.8±11 years. COVID-19 patients with elevated Lp(a) level had significantly longer hospitalization time (11 vs. 9.5 days; p = 0.0362), more extensive radiological changes in CT scan (35 vs. 30%; p = 0.0301) and higher oxygen demand on admission (8 vs. 5L/min; p = 0.0428). Elevated Lp(a) was also associated with significantly higher OR for High Flow Nasal Oxygen Therapy (HFNOT) OR = 3.5 95%CI(1.2;8.9), p = 0.0140, Intubation and ICU OR = 4.1 95%CI(1.1;15.2) p = 0.0423, Death OR = 2.8 95%CI(0.9;8.5), p = 0.0409.

Conclusions

Elevated Lp(a) might be one of the factors which contribute to a more severe course of COVID-19; however, further studies including larger groups of patients are needed.

Development and Validation of an Isoform Independent Monoclonal Antibody-Based ELISA for Measurement of Lipoprotein(a)

The study aims were to develop a new isoform-independent enzyme-linked immunoassay (ELISA) for the measurement of lipoprotein(a) [Lp(a)], validate its performance characteristics, and demonstrate its accuracy by comparison with the gold-standard ELISA method and an LC-MS/MS candidate reference method, both developed at the University of Washington. The principle of the new assay is the capture of Lp(a) with monoclonal antibody LPA4 primarily directed to an epitope in apolipoprotein(a) KIV₂ and its detection with monoclonal antibody LPA-KIV9 directed to a single antigenic site present on KIV₉. Validation studies were performed following the guidelines of the Clinical Laboratory Improvement Amendments and the College of American Pathologists. The analytical measuring range of the LPA4/LPA-KIV9 ELISA is 0.27–1,402 nmol/L, and the method meets stringent criteria for precision, linearity, spike and recovery, dilutability, comparison of plasma versus serum, and accuracy. Method comparison with both the gold-standard ELISA and the LC-MS/MS method performed in 64 samples with known apolipoprotein(a) isoforms resulted in excellent correlation with both methods (r=0.987 and r=0.976, respectively). Additionally, the variation in apolipoprotein(a) size accounted for only 0.2% and 2.2% of the bias variation, respectively, indicating that the LPA4/LPA-KIV9 ELISA is not affected by apolipoprotein(a) size polymorphism. Peptide mapping and competition experiments demonstrated that the measuring monoclonal antibodies used in the gold-standard ELISA (a-40) and in the newly developed ELISA (LPA-KIV9) are directed to the same epitope, ⁴⁰⁷⁶LETPTVV⁴⁰⁸², on KIV₉. In conclusion, no statistically or clinically significant bias was observed between Lp(a) measurements obtained by the LPA4/LPA-KIV9 ELISA and those obtained by the gold-standard ELISA or LC-MS/MS, and therefore, the methods are considered equivalent.

Ten things to know about ten cardiovascular disease risk factors - 2022

The American Society for Preventive Cardiology (ASPC) "Ten things to know about ten cardiovascular disease risk factors - 2022" is a summary document regarding cardiovascular disease (CVD) risk factors. This 2022 update provides summary tables of ten things to know about 10 CVD risk factors and builds upon the foundation of prior annual versions of "Ten things to know about ten cardiovascular disease risk factors" published since 2020. This 2022 version provides the perspective of ASPC members and includes updated sentinel references (i.e., applicable guidelines and select reviews) for each CVD risk factor section. The ten CVD risk factors include unhealthful dietary intake, physical inactivity, dyslipidemia, pre-diabetes/diabetes, high blood pressure, obesity, considerations of select populations (older age, race/ethnicity, and sex differences), thrombosis (with smoking as a potential contributor to thrombosis), kidney dysfunction and genetics/familial hypercholesterolemia. Other CVD risk factors may be relevant, beyond the CVD risk factors discussed here. However, it is the intent of the ASPC "Ten things to know about ten cardiovascular disease risk factors - 2022" to provide a tabular overview of things to know about ten of the most common CVD risk factors applicable to preventive cardiology and provide ready access to applicable guidelines and sentinel reviews.

Lipoprotein(a) and cardiovascular and valvular diseases: A genetic epidemiological perspective

Rates of atherosclerotic cardiovascular diseases (CVD) in the Western world have spectacularly decreased over the past 50 years. However, a substantial proportion of high-risk patients still develop heart attacks, strokes and valvular heart diseases despite benefiting from state-of-the-art treatments including lipid-lowering therapies. Over the past 10-15 years, it has become increasingly clear that Lipoprotein(a) (Lp[a]) is a critical component of this so-called residual risk. Genetic association studies revealed that Lp(a) is robustly, independently and causally associated with a broad range of cardiovascular and valvular heart diseases. Up to 1 billion people around the globe may have an Lp(a) level that places them in a high-risk category. Lp(a) is strongly associated with calcific aortic valve stenosis (CAVS), coronary artery disease (CAD), peripheral arterial disease (PAD) and to a lesser extent with ischemic stroke (IS) and heart failure (HF). Because of this strong association with cardiovascular and valvular heart diseases, Lp(a) even emerged as one of the most important genetic determinants of human lifespan and healthspan. Here, we review the evidence from the largest and most informative genetic association studies and prospective studies that have investigated the association between Lp(a) and human lifespan, healthspan, CVD, CAVS and non-cardiovascular diseases. We present Lp(a) threshold values that may be clinically relevant and identify other cardiovascular risk factors that may modulate the absolute risk of CVD in individuals with high Lp(a) levels. Finally, we identify key clinical and research questions that require further investigation to eventually and optimally reduce CVD risk in patients with high Lp(a) levels.

Lipoprotein(a) and Cardiovascular Outcomes in Patients With Coronary Artery Disease and Different Metabolic Phenotypes

Background

The positive relationship between metabolic healthy obesity (MHO) and cardiovascular risk has been under debate in recent years. Previously, strong evidence supported the causal role of increased plasma lipoprotein(a) [Lp(a)] levels in cardiovascular disease (CVD). The current study aimed to investigate the different associations of Lp(a) and cardiovascular events (CVEs) in patients with coronary artery disease (CAD) and different metabolic phenotypes.

Methods

A total of 5,089 patients who were angiography-proven CAD were consecutively included and followed up for CVEs. Obesity was defined as a body mass index (BMI) ≥25 kg/m² according to Asia-specific BMI criteria. Patients were divided into four groups according to metabolic phenotypes, namely metabolically healthy/unhealthy non-obese and metabolically healthy/unhealthy obese [metabolically healthy non-obese (MHN), MHO, metabolically unhealthy non-obese (MUN), and metabolically unhealthy obesity (MUO)]. Comparisons of CAD severity and outcomes were performed among four groups. Cox regression analyses and cubic spline models were used to examine the relationship between Lp(a) and CVEs in patients with different metabolic phenotypes.

Results

During a median of 7.5 years’ follow-up, 540 (10.6%) CVEs occurred. MUN and MUO populations had more severe coronary stenosis than MHN ones, while no significant difference in the Gensini score (GS) was observed between MHN and MHO. Patients with MUN and MUO presented a higher risk of CVEs than patients with MHN (hazard ratio [HR]: 1.414, 95% CI: 1.024–1.953–1.556 and HR: 1.747, 95% CI: 1.295–1.363, p < 0.05). In subgroup analysis, restricted cubic spline models showed that there was no association between Lp(a) and CVEs in patients in MHN and MHO, while the MUN and MUO groups presented increasing associations between Lp(a) and CVEs and such association was stronger in the MUO group. In Cox regression analysis, Lp(a) >50 mg/dl was associated with a 2.032- and 2.206-fold higher risk of subsequent CVEs in the MUO and MUN subgroups, respectively.

Conclusion

Among patients with angiography-proven stable CAD, Lp(a) had a more significant prognostic value in both MUO and MUN individuals regardless of obesity, suggesting the importance of screening for cardiovascular risk with Lp(a) in metabolically unhealthy patients.

Familial Hypercholesterolemia and Elevated Lipoprotein(a): Cascade Testing and Other Implications for Contextual Models of Care

Elevated lipoprotein(a) [Lp(a)], a predominantly genetic disorder, is a causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valvular disease, particularly in patients with familial hypercholesterolemia (FH), a Tier I genomic condition. The combination from birth of the cumulative exposure to elevated plasma concentrations of both Lp(a) and low-density lipoprotein is particularly detrimental and explains the enhanced morbidity and mortality risk observed in patients with both conditions. An excellent opportunity to identify at-risk patients with hyper-Lp(a) at increased risk of ASCVD is to test for hyper-Lp(a) during cascade testing for FH. With probands having FH and hyper-Lp(a), the yield of detection of hyper-Lp(a) is 1 individual for every 2.1-2.4 relatives tested, whereas the yield of detection of both conditions is 1 individual for every 3-3.4 relatives tested. In this article, we discuss the incorporation of assessment of Lp(a) in the cascade testing in FH as a feasible and crucial part of models of care for FH. We also propose a simple management tool to help physicians identify and manage elevated Lp(a) in FH, with implications for the care of Lp(a) beyond FH, noting that the clinical use of RNA therapeutics for specifically targeting the overproduction of Lp(a) in at risk patients is still under investigation.

How Do Lipoprotein(a) Concentrations Affect Clinical Outcomes for Patients With Stable Coronary Artery Disease Who Underwent Different Dual Antiplatelet Therapy After Percutaneous Coronary Intervention?

Background Lp(a) (lipoprotein[a]) plays an important role in predicting cardiovascular events in patients with coronary artery disease through its proatherogenic and prothrombotic effects. We hypothesized that prolonged dual antiplatelet therapy (DAPT) might be beneficial for patients undergoing percutaneous coronary intervention who had elevated Lp(a) levels. This study aimed to evaluate the effect of Lp(a) on the efficacy and safety of prolonged DAPT versus shortened DAPT in stable patients with coronary artery disease who were treated with a drug-eluting stent. Methods and Results We selected 3201 stable patients with CAD from the prospective Fuwai Percutaneous Coronary Intervention Registry, of which 2124 patients had Lp(a) ≤30 mg/dL, and 1077 patients had Lp(a) >30 mg/dL. Patients were divided into 4 groups according to Lp(a) levels and the duration of DAPT therapy (≤1 year versus >1 year). The primary end point was major adverse cardiovascular and cerebrovascular event, defined as a composite of all-cause death, myocardial infarction, or stroke. The median follow-up time was 2.5 years. Among patients with elevated Lp(a) levels, DAPT >1 year presented lower risk of major adverse cardiovascular and cerebrovascular event and definite/probable stent thrombosis compared with DAPT ≤1 year. In contrast, in patients with normal Lp(a) levels, the risks of major adverse cardiovascular and cerebrovascular event and definite/probable stent thrombosis were not significantly different between the DAPT >1 year and DAPT ≤1 year groups. Prolonged DAPT had 2.4-times higher risk of clinically relevant bleeding than shortened DAPT in patients with normal Lp(a) levels, although without statistical difference. Conclusions In stable patients with coronary artery disease, who underwent percutaneous coronary intervention with a drug-eluting stent, prolonged DAPT was associated with reduced risk of cardiovascular events among those with elevated Lp(a) levels, whereas it did not show statistically significant evidence of benefit for reducing ischemic events and tended to increase clinically relevant bleeding among those with normal Lp(a) levels.

Effect of PCSK9 Inhibitor on Blood Lipid Levels in Patients with High and Very-High CVD Risk: A Systematic Review and Meta-Analysis

Objectives

We aimed to investigate the effects of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor on blood lipid levels in patients with high and very-high cardiovascular risk.

Design

14 trials (n = 52,586 patients) comparing treatment with or without PCSK9 inhibitors were retrieved from PubMed and Embase updated to 1st Jun 2021. The data quality of included studies was assessed by two independent researchers using the Cochrane systematic review method. All-cause mortality, cardiovascular mortality, and changes in serum low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglyceride (TG), apolipoprotein B (ApoB), lipoprotein (a) (LP (a)), non-high-density lipoprotein cholesterol (non-HDL-C), high-density lipoprotein cholesterol (HDL-C), and apolipoprotein A1 (ApoA1) from baseline were analyzed using Rev Man 5.1.0 software.

Results

Compared with treatments without PCSK9 inhibitor, addition of PCSK9 inhibitors (evolocumab and alirocumab) had obvious decreasing effects on the levels of LDL-C [MD = −46.86, 95% CI (−54.99 to −38.72), P < 0.00001], TC [MD = −31.92, 95% CI (−39.47 to −24.38), P < 0.00001], TG [MD = −8.13, 95% CI (−10.48 to −5.79), P < 0.00001], LP(a) [MD = −26.69, 95% CI (-27.93 to −25.44), P < 0.00001], non-HDL-C [MD = −42.86, 95% CI (−45.81 to −39.92), P < 0.00001], and ApoB [MD = −38.44, 95% CI (−42.23 to -34.65), P < 0.00001] in high CVD risk patients. Conversely, changes of HDL-C [MD = 6.27, CI (5.17 to 7.36), P < 0.00001] and ApoA1 [MD = 4.33, 95% CI (3.53 to 5.13), P < 0.00001] from baseline were significantly more in high cardiovascular disease risk patients who received PCSK9 inhibitors treatment.

Conclusion

Addition of PCSK9 inhibitors to standard therapy resulted in definite improvement in blood lipid levels compared with therapies that did not include them.

Elevated lipoprotein (a) levels and risk of peripheral artery disease outcomes: A systematic review

BACKGROUND

Despite strong association of elevated lipoprotein (a) (Lp(a)) levels with incident coronary and cerebrovascular disease, data for incident peripheral artery disease (PAD) are less robust. The main objective of the present systematic review was to analyze the association between elevated Lp(a) levels and PAD outcomes.

METHODS

This systematic review was performed according to PRISMA guidelines. A literature search was performed to detect randomized clinical trials or observational studies with a cohort design that evaluated the association between Lp(a) levels and PAD outcomes.

RESULTS

Fifteen studies including 493,650 subjects were identified and considered eligible for this systematic review. This systematic review showed that the vast majority of the studies reported a significant association between elevated Lp(a) levels and the risk of PAD outcomes. The elevated Lp(a) levels were associated with a higher risk of incident claudication (RR: 1.20), PAD progression (HR: 1.41), restenosis (HR: 6.10), death and hospitalization related to PAD (HR: 1.37), limb amputation (HR: 22.75), and lower limb revascularization (HR: 1.29 and 2.90). In addition, the presence of elevated Lp(a) values were associated with a higher risk of combined PAD outcomes, with HRs in a range between 1.14 and 2.80, despite adjusting for traditional risk factors. Heterogeneity of results can be explained by different patient populations studied and varying Lp(a) cut-off points of Lp(a) analyzed.

CONCLUSION

This systematic review suggests that evidence is available to support an independent positive association between Lp(a) levels and the risk of future PAD outcomes. PROSPERO Registration No.: 289253.

Sortilin enhances secretion of apolipoprotein(a) through effects on apolipoprotein B secretion and promotes uptake of lipoprotein(a)

Elevated plasma lipoprotein(a) (Lp(a)) is an independent, causal risk factor for atherosclerotic cardiovascular disease and calcific aortic valve stenosis. Lp(a) is formed in or on hepatocytes from successive noncovalent and covalent interactions between apo(a) and apoB, although the subcellular location of these interactions and the nature of the apoB-containing particle involved remain unclear. Sortilin, encoded by the SORT1 gene, modulates apoB secretion and LDL clearance. We used a HepG2 cell model to study the secretion kinetics of apo(a) and apoB. Overexpression of sortilin increased apo(a) secretion, while siRNA-mediated knockdown of sortilin expression correspondingly decreased apo(a) secretion. Sortilin binds LDL but not apo(a) or Lp(a), indicating that its effect on apo(a) secretion is likely indirect. Indeed, the effect was dependent on the ability of apo(a) to interact noncovalently with apoB. Overexpression of sortilin enhanced internalization of Lp(a), but not apo(a), by HepG2 cells, although neither sortilin knockdown in these cells or Sort1 deficiency in mice impacted Lp(a) uptake. We found several missense mutations in SORT1 in patients with extremely high Lp(a) levels; sortilin containing some of these mutations was more effective at promoting apo(a) secretion than WT sortilin, though no differences were found with respect to Lp(a) internalization. Our observations suggest that sortilin could play a role in determining plasma Lp(a) levels and corroborate in vivo human kinetic studies which imply that secretion of apo(a) and apoB are coupled, likely within the hepatocyte.

Oxidized phospholipids and lipoprotein(a): An update

Over the past few years, there has been an undiminished interest in lipoprotein(a) [Lp(a)] and oxidized phospholipids (OxPLs), mainly carried on this lipoprotein. Elevated Lp(a) has been established as an independent causal risk factor for cardiovascular disease. OxPLs play an important role in atherosclerosis. The main questions that remain to be answered, however, is to what extent OxPLs contribute to the atherogenicity of Lp(a), what effect hypolipidaemic medications may have on their levels and the potential clinical benefit of their reduction. This narrative review aimed to summarize currently available data on OxPLs and cardiovascular risk, as well as the effect of established and emerging hypolipidaemic medications on Lp(a)-OxPLs.

Atherothrombotic factors and atherosclerotic cardiovascular events: the multi-ethnic study of atherosclerosis

AIMS

Traditional atherosclerotic cardiovascular disease (ASCVD) risk factors fail to address the full spectrum of the complex interplay of atherosclerotic and atherothrombotic factors integral to ASCVD events. This study sought to examine the association between atherothrombotic biomarkers and ASCVD events.

METHODS AND RESULTS

The association between atherothrombotic biomarkers and 877 ASCVD events with and without adjustment for traditional risk factors was evaluated via Cox proportional hazards models and factor analysis in 5789 Multi-Ethnic Study of Atherosclerosis participants over a median follow-up of 14.7 years. Factor analysis accounted for multidimensional relationship and shared variance among study biomarkers, which identified two new variables: a thrombotic factor (Factor 1), principally defined by shared variance in fibrinogen, plasmin-antiplasmin complex, factor VIII, D-dimer, and lipoprotein(a), and a fibrinolytic factor (Factor 2), principally defined by shared variance of plasminogen and oxidized phospholipids on plasminogen. In a model including both factors, the thrombotic factor was associated with the higher risk of ASCVD events [hazard ratio (HR) 1.57, 95% confidence interval (CI) 1.45, 1.70], while the fibrinolytic factor was associated with the lower risk of ASCVD events (HR 0.76, 95% CI 0.70, 0.82), with estimated ASCVD free survival highest for low atherothrombotic Factor 1 and high atherothrombotic Factor 2.

CONCLUSION

Two atherothrombotic factors, one representative of thrombotic propensity and the other representative of fibrinolytic propensity, were significantly and complementarily associated with incident ASCVD events, remained significantly associated with incident ASCVD after controlling for traditional risk factors, and have promise for identifying patients at high ASCVD event risk specifically due to their atherothrombotic profile.

Value of repeated measurements of lipoprotein (a) to assess cardiovascular risk: a retrospective study

Background: High plasma concentrations of lipoprotein (a) [Lp(a)] are associated with an increased cardiovascular risk. Current guidelines recommend measurement of only a single Lp(a) in an individual's lifetime under specific circumstances to improve cardiovascular risk prediction. Accordingly, the question raised is the number of false positives and negatives missed through only a single measurement.Methods: All Lp(a) measurements between 2004 and March 2021 were retrieved from the laboratory database of the Erasme hospital. Only patients with repeated measurement were included. The first and subsequent Lp(a) measurement were compared. Two different cohorts were studied as a result of a change in Lp(a) determination methodology (n = 2049 and n = 309, respectively). The effects of a third Lp(a) measurement were assessed through binary analyses (n = 678). The 180 mg/dl (430 nmol/L) threshold recommended in the ESC guidelines was assessed first. Analysis was repeated for 100, 70 and 50 mg/dl thresholds of raised Lp(a) levels.Results: A low rate of false negatives (0.8%-1%) and false positives (0.6-0.3%) were revealed with two Lp(a) measurements. There was no difference in regards to the divergent Lp(a) thresholds nor the measurement of Lp(a) on two or three occasions.Conclusion: The present study showed Lp(a) determination to be reproducible. A single measurement is sufficient to assess if a patient exceeds various cut-off values of elevated Lp(a) levels.

Impact of Fetuin-A, Lp(a), matrix gla protein and macrophage density on calcific aortic valve disease: a clinical study

BACKGROUND

Calcific aortic valve disease (CAVD) has a substantial and increasing burden in the ageing population with occult onset.Present study aimed to assess association of clinical characteristics of these patients and occurrence of CAVD.

METHODS

Patients diagnosed with CAVD and those receiving healthy medical examination in our hospital from January 2019 to February 2021 were enrolled in this retrospective study. Clinical characteristics, ultrasonic indicators, serological indicators and histology of CAVD were collected and compared among different groups. Logistic regression and Pearson correlation analysis was used to explore relationship between these indexes and occurrence of CAVD.

RESULTS

DBP, SBP, LVESD, LVEDD, IVS, PW, AV Vmax, TC, TG, LDL-C, Fetuin-A, Lp(a) in severe group were higher than mild, moderate and control groups (P<0.05), while those indexes of patients in moderate group were higher than that in mild and controlled groups (P<0.05). Besides, theses indexes of patients in mild group were also higher than that of controlled one (P<0.05). However, LVEF, HDL-C and MGP of patients in severe group was the lowest (P<0.05), while those in moderate group were lower than mild and controlled groups. Moreover, these indexes in mild group were also lower than control group (P<0.05). In Logistic regression analysis, MGP, Fetuin-A and Lp(a) were all independently associated with occurrence of CAVD (P<0.05). In Pearson correlation analysis, Fetuin-A and Lp(a) were positively correlated with progression of the disease, while MGP and macrophage density were negatively correlated with it.

CONCLUSIONS

Fetuin-A, MPG and Lp(a) were independently associated with the occurrence of CAVD, and they might be potential predictors for diagnosis of this disease.

Apo(a) and ApoB Interact Noncovalently Within Hepatocytes: Implications for Regulation of Lp(a) Levels by Modulation of ApoB Secretion

BACKGROUND

Elevated plasma Lp(a) (lipoprotein(a)) levels are associated with increased risk for atherosclerotic cardiovascular disease and aortic valve stenosis. However, the cell biology of Lp(a) biosynthesis remains poorly understood, with the locations of the noncovalent and covalent steps of Lp(a) assembly unclear and the nature of the apoB-containing particle destined for Lp(a) unknown. We, therefore, asked if apo(a) and apoB interact noncovalently within hepatocytes and if this impacts Lp(a) biosynthesis.

METHODS

Using human hepatocellular carcinoma cells expressing 17K (17 kringle) apo(a), or a 17KΔLBS7,8 variant with a reduced ability to bind noncovalently to apoB, we performed coimmunoprecipitation, coimmunofluorescence, and proximity ligation assays to document intracellular apo(a):apoB interactions. We used a pulse-chase metabolic labeling approach to measure apo(a) and apoB secretion rates.

RESULTS

Noncovalent complexes containing apo(a)/apoB are present in lysates from cells expressing 17K but not 17KΔLBS7,8, whereas covalent apo(a)/apoB complexes are absent from lysates. 17K and apoB colocalized intracellularly, overlapping with staining for markers of endoplasmic reticulum trans-Golgi, and early endosomes, and less so with lysosomes. The 17KΔLBS7,8 had lower colocalization with apoB. Proximity ligation assays directly documented intracellular 17K/apoB interactions, which were dramatically reduced for 17KΔLBS7,8. Treatment of cells with PCSK9 (proprotein convertase subtilisin/kexin type 9) enhanced, and lomitapide reduced, apo(a) secretion in a manner dependent on the noncovalent interaction between apo(a) and apoB. Apo(a) secretion was also reduced by siRNA-mediated knockdown of APOB.

CONCLUSIONS

Our findings explain the coupling of apo(a) and Lp(a)-apoB production observed in human metabolic studies using stable isotopes as well as the ability of agents that inhibit apoB biosynthesis to lower Lp(a) levels.

The dawn of a new era of targeted lipid-lowering therapies

Lipid risk factors for cardiovascular disease depend in part on lifestyle, but optimum control of lipids often demands additional measures. Low-density lipoprotein (LDL) doubtless contributes causally to atherosclerosis. Recent human genetic findings have substantiated a number of novel targets for lipid-lowering therapy including apolipoprotein C-III, angiopoietin-like protein 3 and 4, apolipoprotein V, and ATP citrate lyase. These discoveries coupled with advances in biotechnology development afford new avenues for management of LDL and other aspects of lipid risk. Beyond LDL, new treatments targeting triglyceride-rich lipoproteins and lipoprotein(a) have become available and have entered clinical development. Biological and RNA-directed agents have joined traditional small-molecule approaches, which themselves have undergone considerable refinement. Innovative targeting strategies have increased efficacy of some of these novel interventions and markedly improved their tolerability. Gene-editing approaches have appeared on the horizon of lipid management. This article reviews this progress offering insight into novel biological and therapeutic discoveries, and places them into a practical patient care perspective.

Lipoprotein(a) Levels at Birth and in Early Childhood: The COMPARE Study

BACKGROUND AND OBJECTIVE

High lipoprotein(a) is a genetically determined causal risk factor for cardiovascular disease, and 20% of the adult population has high levels (ie, >42 mg/dL, >88 nmol/L). We investigated whether early life lipoprotein(a) levels measured in cord blood may serve as a proxy for neonatal venous blood levels, whether lipoprotein(a) birth levels (ie, cord or venous) predict levels later in life, and whether early life and parental levels correlate.

METHODS

The Compare study is a prospective cohort study of newborns (N = 450) from Copenhagen, Denmark, including blood sampling of parents. Plasma lipoprotein(a) was measured in cord blood (N = 402), neonatal venous blood (N = 356), and at 2 (N = 320) and 15 months follow-up (N = 148) of infants, and in parents (N = 705).

RESULTS

Mean lipoprotein(a) levels were 2.2 (95% CI, 1.9-2.5), 2.4 (2.0-2.7), 4.1 (3.4-4.9), and 14.6 (11.4-17.9) mg/dL in cord, neonatal venous, and 2- and 15-month venous samples, respectively. Lipoprotein(a) levels in cord blood correlated strongly with neonatal venous blood levels (R2 = 0.95, P < 0.001) and neonatal levels correlated moderately with 2- and 15-month levels (R2 = 0.68 and 0.67, both P < 0.001). Birth levels ≥ 90th percentile predicted lipoprotein(a) > 42 mg/dL at 15 months with positive predictive values of 89% and 85% for neonatal venous and cord blood. Neonatal and infant levels correlated weakly with parental levels, most pronounced at 15 months (R2 = 0.22, P < 0.001).

CONCLUSIONS

Lipoprotein(a) levels are low in early life, cord blood may serve as a proxy for neonatal venous blood, and birth levels ≥ 90th percentile can identify newborns at risk of developing high levels.

Elevated Lipoprotein(a) Level Influences Familial Hypercholesterolemia Diagnosis

Familial hypercholesterolemia (FH) and elevated lipoprotein(a) [Lp(a)] level are the most common inherited disorders of lipid metabolism. This study evaluated the impact of high Lp(a) level on accuracy Dutch Lipid Clinic Network (DLCN) criteria of heterozygous FH diagnosis. A group of 206 individuals not receiving lipid-lowering medication with low-density lipoprotein cholesterol (LDL-C) >4.9 mmol/L was chosen from the Russian FH Registry. LDL-C corrected for Lp(a)-cholesterol was calculated as LDL-C − 0.3 × Lp(a). DLCN criteria were applied before and after adjusting LDL-C concentration. Of the 206 patients with potential FH, a total of 34 subjects (17%) were reclassified to less severe FH diagnosis, 13 subjects of them (6%) were reclassified to “unlike” FH. In accordance with Receiver Operating Characteristic curve, Lp(a) level ≥40 mg/dL was associated with FH re-diagnosing with sensitivity of 63% and specificity of 78% (area under curve = 0.7, 95% CI 0.7−0.8, p < 0.001). The reclassification was mainly observed in FH patients with Lp(a) level above 40 mg/dL, i.e., 33 (51%) with reclassified DLCN criteria points and 22 (34%) with reclassified diagnosis, compared with 21 (15%) and 15 (11%), respectively, in patients with Lp(a) level less than 40 mg/dL. Thus, LDL-C corrected for Lp(a)-cholesterol should be considered in all FH patients with Lp(a) level above 40 mg/dL for recalculating points in accordance with DLCN criteria.

Assessing the Accuracy of Estimated Lipoprotein(a) Cholesterol and Lipoprotein(a)-Free Low-Density Lipoprotein Cholesterol

Background

Accurate measurement of the cholesterol within lipoprotein(a) (Lp[a]‐C) and its contribution to low‐density lipoprotein cholesterol (LDL‐C) has important implications for risk assessment, diagnosis, and treatment of atherosclerotic cardiovascular disease, as well as in familial hypercholesterolemia. A method for estimating Lp(a)‐C from particle number using fixed conversion factors has been proposed (Lp[a]‐C from particle number divided by 2.4 for Lp(a) mass, multiplied by 30% for Lp[a]‐C). The accuracy of this method, which theoretically can isolate “Lp(a)‐free LDL‐C,” has not been validated.

Methods and Results

In 177 875 patients from the VLDbL (Very Large Database of Lipids), we compared estimated Lp(a)‐C and Lp(a)‐free LDL‐C with measured values and quantified absolute and percent error. We compared findings with an analogous data set from the Mayo Clinic Laboratory. Error in estimated Lp(a)‐C and Lp(a)‐free LDL‐C increased with higher Lp(a)‐C values. Median error for estimated Lp(a)‐C <10 mg/dL was −1.9 mg/dL (interquartile range, −4.0 to 0.2); this error increased linearly, overestimating by +30.8 mg/dL (interquartile range, 26.1–36.5) for estimated Lp(a)‐C ≥50 mg/dL. This error relationship persisted after stratification by overall high‐density lipoprotein cholesterol and high‐density lipoprotein cholesterol subtypes. Similar findings were observed in the Mayo cohort. Absolute error for Lp(a)‐free LDL‐C was +2.4 (interquartile range, −0.6 to 5.3) for Lp(a)‐C<10 mg/dL and −31.8 (interquartile range, −37.8 to −26.5) mg/dL for Lp(a)‐C≥50 mg/dL.

Conclusions

Lp(a)‐C estimations using fixed conversion factors overestimated Lp(a)‐C and subsequently underestimated Lp(a)‐free LDL‐C, especially at clinically relevant Lp(a) values. Application of inaccurate Lp(a)‐C estimations to correct LDL‐C may lead to undertreatment of high‐risk patients.

Lipoprotein(a): A Genetically Determined, Causal, and Prevalent Risk Factor for Atherosclerotic Cardiovascular Disease: A Scientific Statement From the American Heart Association

High levels of lipoprotein(a) [Lp(a)], an apoB100-containing lipoprotein, are an independent and causal risk factor for atherosclerotic cardiovascular diseases through mechanisms associated with increased atherogenesis, inflammation, and thrombosis. Lp(a) is predominantly a monogenic cardiovascular risk determinant, with ≈70% to ≥90% of interindividual heterogeneity in levels being genetically determined. The 2 major protein components of Lp(a) particles are apoB100 and apolipoprotein(a). Lp(a) remains a risk factor for cardiovascular disease development even in the setting of effective reduction of plasma low-density lipoprotein cholesterol and apoB100. Despite its demonstrated contribution to atherosclerotic cardiovascular disease burden, we presently lack standardization and harmonization of assays, universal guidelines for diagnosing and providing risk assessment, and targeted treatments to lower Lp(a). There is a clinical need to understand the genetic and biological basis for variation in Lp(a) levels and its relationship to disease in different ancestry groups. This scientific statement capitalizes on the expertise of a diverse basic science and clinical workgroup to highlight the history, biology, pathophysiology, and emerging clinical evidence in the Lp(a) field. Herein, we address key knowledge gaps and future directions required to mitigate the atherosclerotic cardiovascular disease risk attributable to elevated Lp(a) levels.

Lipoprotein(a)—The Crossroads of Atherosclerosis, Atherothrombosis and Inflammation

Increased lipoprotein(a) (Lp(a)) levels are an independent predictor of coronary artery disease (CAD), degenerative aortic stenosis (DAS), and heart failure independent of CAD and DAS. Lp(a) levels are genetically determinated in an autosomal dominant mode, with great intra- and inter-ethnic diversity. Most variations in Lp(a) levels arise from genetic variations of the gene that encodes the apolipoprotein(a) component of Lp(a), the LPA gene. LPA is located on the long arm of chromosome 6, within region 6q2.6–2.7. Lp(a) levels increase cardiovascular risk through several unrelated mechanisms. Lp(a) quantitatively carries all of the atherogenic risk of low-density lipoprotein cholesterol, although it is even more prone to oxidation and penetration through endothelia to promote the production of foam cells. The thrombogenic properties of Lp(a) result from the homology between apolipoprotein(a) and plasminogen, which compete for the same binding sites on endothelial cells to inhibit fibrinolysis and promote intravascular thrombosis. LPA has up to 70% homology with the human plasminogen gene. Oxidized phospholipids promote differentiation of pro-inflammatory macrophages that secrete pro-inflammatory cytokines (e. g., interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor-α). The aim of this review is to define which of these mechanisms of Lp(a) is predominant in different groups of patients.

Benefit and Risk of Prolonged Dual Antiplatelet Therapy After Percutaneous Coronary Intervention With Drug-Eluting Stents in Patients With Elevated Lipoprotein(a) Concentrations

Background: Lipoprotein(a) is positively related to cardiovascular events in patients with coronary artery disease (CAD). Given that lipoprotein(a) has a prothrombotic effect, prolonged dual antiplatelet therapy (DAPT) might have a beneficial effect on reducing ischemic events in patients with elevated lipoprotein(a) levels after percutaneous coronary intervention (PCI). We performed this study to assess the efficacy and safety of prolonged DAPT (>1 year) in this population.

Methods: We evaluated a total of 3,025 CAD patients with elevated lipoprotein(a) levels who were event-free at 1 year after PCI from the prospective Fuwai PCI Registry, of which 913 received DAPT ≤ 1 year and 2,112 received DAPT>1 year. The primary endpoint was major adverse cardiovascular and cerebrovascular event (MACCE), defined as a composite of all-cause death, myocardial infarction or stroke.

Results: After a median follow-up of 2.4 years, patients who received DAPT>1 year were associated with lower risks of MACCE compared with DAPT ≤ 1 year (1.6 vs. 3.8%; hazard ratio [HR] 0.383, 95% confidence interval [CI] 0.238–0.616), which was primarily driven by the lower all-cause mortality (0.2 vs. 2.3%; HR 0.078, 95% CI 0.027–0.227). In addition, DAPT>1 year was also associated with lower risks of cardiac death, and definite/probable stent thrombosis than those who received DAPT ≤ 1 year (P < 0.05). Conversely, no difference was found between the two groups in terms of clinically relevant bleeding. Similar results were observed in multivariate Cox regression analysis and inverse probability of treatment weighting analysis.

Conclusions: In patients with elevated lipoprotein(a) concentrations after PCI, prolonged DAPT (>1 year) reduced ischemic cardiovascular events, including MACCE, all-cause mortality, cardiac mortality, and definite/probable stent thrombosis, without increase in clinically relevant bleeding risk compared with ≤ 1-year DAPT. Lipoprotein(a) levels might be a new important consideration when deciding the duration of DAPT after PCI.

Recent dynamic studies of the metabolism of atherogenic lipoproteins: elucidating the mode of action of new therapies

PURPOSE OF REVIEW

LDL, triglyceride-rich lipoprotein (TRL) and lipoprotein(a) [Lp(a)] particles are the key atherogenic lipoproteins. Deranged metabolism of these lipoproteins accounts for a spectrum of clinically important dyslipidemias, such as FH, elevated Lp(a) and diabetic dyslipidemia. We review the findings from recent dynamic and tracer studies that have contributed to expanding knowledge in this field.

RECENT FINDINGS

Deficiency in LDL receptor activity does not only impair the catabolism of LDL-apoB-100 in FH, but also induces hepatic overproduction and decreases catabolism of TRLs. Patients with elevated Lp(a) are characterized by increased hepatic secretion of Lp(a) particles. Elevation of TRLs in diabetes is partly mediated by increased production of apoB-48 and apoC-III, and impaired clearance of apoB-48 in the postprandial state. Tracer kinetic studies show that proprotein convertase subtilisin/kexin type 9 mAbs alone or in combination with statin can increase the catabolism and decrease production of LDL and Lp(a) particles. By contrast, angiopoietin-like protein 3 inhibitors (e.g. evinacumab) reduce VLDL production and increase LDL clearance in FH. Glucagon-like peptide-1 receptor agonists can improve diabetic dyslipidemia by increasing the catabolism of apoB-48 and decreasing the production of apoB-48 and apoC-III.

SUMMARY

Dynamic studies of the metabolism of atherogenic lipoproteins provide new insight into the nature of dyslipidemias and point to how new therapies with complementary modes of action may have maximal clinical impact.

Association between lipoprotein (a) and heart failure with reduced ejection fraction development

Background

The current study aimed to evaluate the relationship between baseline serum lipoprotein (a) [Lp(a)] level and heart failure with reduced ejection fraction (HFrEF) development.

Methods

This was a retrospective study, and participants were enrolled from the outpatient clinic. All data were extracted from the electronic health record of the outpatient clinic system. The follow‐up was performed through reviewing the clinical notes at the outpatient clinic system, and study outcome of the current study was the first diagnosis of HFrEF. Participants were divided into low Lp(a) (<30 mg/dl, n = 336) and high Lp(a) (≥30 mg/dl, n = 584) groups.

Results

Individuals in the high Lp(a) group were more likely to be men and have diabetes mellitus (DM) and dyslipidemia. Increased Lp(a) at baseline was positively associated with serum N‐terminal pro‐B natriuretic peptide level while negatively associated with left ventricular ejection fraction (LVEF) at follow‐up. After adjusting for covariates, per 10 mg/dl increase in baseline Lp(a) remained significantly associated with HFrEF, with odds ratio of 1.17 (95% confidence interval of 1.05, 1.46). The magnitude of association between baseline Lp(a) level and HFrEF was greater in men and in individuals with DM or coronary heart disease (CHD), while it was weaker in individuals treated with beta‐blocker at baseline.

Conclusion

Increased Lp(a) at baseline was associated with HFrEF development. The adverse effects of Lp(a) were greater on men and individuals with DM or CHD, which were mitigated by beta‐blocker therapy. These findings together underscore the possibility and usefulness of Lp(a) as a new risk factor to predict HFrEF.

Dyslipidemia and aortic valve disease

PURPOSE OF REVIEW

Degenerative aortic stenosis (AS) is one of the most prevalent heart valve diseases in the adult population. The understanding of AS pathophysiology and involved risk factors have recently undergone a great advance, with low-density lipoprotein cholesterol (LDL-C), lipoprotein (a) [Lp(a)] and other clinical conditions taking on a relevant role. Although little is known about the prevention of AS, we can progressively find more evidence of the possible use of drugs to control risk factors as tools that may delay the progression to severe AS and aortic valve replacement.

RECENT FINDINGS

Several factors have shown to be solid predictors of the development of AS. Mendelian randomization and observational studies on risk factors specifically lipid factors, such as hypercholesterolemia, Lp(a), proprotein convertase subtilisin/kexin type 9 and hypertension have provided meaningful new information. The SAFEHEART study has significantly contributed to define the role of LDL-C and Lp(a) in AS.

SUMMARY

In this review we discuss the interrelationship of dyslipidemia, especially hypercholesterolemia and Lp(a) in the development and prognosis of valvular AS. New imaging tools may contribute to its early detection. Future studies with proprotein convertase subtilisin/kexin type 9 inhibitors and specific therapies to lower Lp(a) might contribute to delay AS development.