Genetic Counseling and Genetic Testing for Familial Hypercholesterolemia.

Familial hypercholesterolemia (FH) is one of the most common autosomal codominant Mendelian diseases. The major complications of FH include tendon and cutaneous xanthomas and coronary artery disease (CAD) associated with a substantial elevation of serum low-density lipoprotein levels (LDL). Genetic counseling and genetic testing for FH is useful for its diagnosis, risk stratification, and motivation for further LDL-lowering treatments. In this study, we summarize the epidemiology of FH based on numerous genetic studies, including its pathogenic variants, genotype-phenotype correlation, prognostic factors, screening, and usefulness of genetic counseling and genetic testing. Due to the variety of treatments available for this common Mendelian disease, genetic counseling and genetic testing for FH should be implemented in daily clinical practice.

Putative Pathogenic Variants of ABCG5 and ABCG8 of Sitosterolemia in Patients With Hyper-Low-Density Lipoprotein Cholesterolemia.

Objective: Sitosterolemia is a rare autosomal recessive disease caused by the deleterious variants of adenosine 5'-triphosphate (ATP)-binding cassette sub-family G member 5 (ABCG5) or ATP-binding cassette sub-family G member 8 (ABCG8). There are only few data on the pathogenicity of ABCG5 and ABCG8. This study aimed to propose a scheme for determining variant pathogenicity and to catalog the putative pathogenic variants in sitosterolemia. Methods: This study enrolled 377 consecutive Japanese patients with hyper-low-density lipoprotein cholesterolemia (mean age: 46.5±19.8 years, with 192 men) who have targeted-sequenced data on ABCG5 or ABCG8 (among 21 Mendelian lipid genes for any dyslipidemias) and serum sitosterol levels at Kanazawa University Hospital from 2016 to 2021. Serum sitosterol levels were divided by 0.79 in patients treated with ezetimibe, accounting for the average reduction with this drug. ABCG5 or ABCG8 variants were defined as putative pathogenic if associated with serum sitosterol levels ≥5 µg/mL or homozygous if associated with serum sitosterol levels ≥10 µg/mL. Results: Twenty-three ABCG5 or ABCG8 variants (16 missense, 2 nonsense, 2 frameshift, 2 deletion, and 1 splice mutation) were identified. Based on our definition, 11 putative pathogenic variants (median sitosterol level: 10.1 [6.5-17.1] µg/mL) were found in 36 individuals and 12 benign variants (median sitosterol: 3.5 [2.5-4.1] µg/mL) in 14 individuals. Conclusion: The scheme proposed for assessing the pathogenicity of genetic variations (ABCG5 and ABCG8) is useful. Using this scheme, 11 putative pathogenic, and 12 benign variants in ABCG5 or ABCG were classified.

Impact of the severe familial hypercholesterolemia status on atherosclerotic risks.

Risks of atherosclerotic events substantially vary even among patients with familial hypercholesterolemia (FH) with extremely high risk based on life-long exposure to high low-density lipoprotein cholesterol levels. This study aimed to examine the impact of the severe FH status defined by the International Atherosclerosis Society (IAS). Data of patients with FH (N = 1050, male = 490) who were admitted to Kanazawa University Hospital between 2000 and 2020 and who were followed up were retrospectively reviewed. The number of major adverse cardiac events (MACEs), including mortality associated with cardiovascular disease, acute coronary syndrome, and ischemic heart disease requiring coronary revascularization per 1000 person-years, was calculated. Hazard ratio was also calculated using Cox proportional model. Overall, 545 (51.9%) patients had severe FH. The median follow-up duration was 12.6 years. In total, 171 MACEs were recorded during the follow-up period. Severe FH was significantly associated with MACE (hazard ratio = 6.48, 95% confidence interval = 2.56-10.40, P = 1.2 × 10-5). The event rates per 1000 person-years in the primary prevention group of non-severe FH and severe FH, were 0.0 and 15.6, respectively. The event rates per 1000 person-years in the secondary prevention group of non-severe FH and severe FH, were 2.0 and 32.3, respectively. Patients with severe FH exhibited significantly higher risks in primary and secondary prevention settings. This simple criterion provides useful information for identifying patients with even higher risk who may need further management.

Impact of providing genetics-based future cardiovascular risk on LDL-C in patients with familial hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) is an autosomal dominant monogenic disease characterized by high low-density lipoprotein cholesterol (LDL-C) levels. Although carrying causative FH variants is associated with coronary heart disease (CHD), it remains unclear whether disclosing its associated cardiovascular risk affects outcomes in patients with FH. OBJECTIVE: We aimed to evaluate the efficacy of providing future cardiovascular risk based on genetic testing in addition to a standard FH education program. METHODS: We conducted a randomized, wait-list controlled, open-label, single-center trial. In the intervention group, we reported a future cardiovascular risk based on the genetic testing adding to standard FH education at week 0. In the wait-list control group, we only disseminated standard FH education according to the guidelines at week 0; they later received a genetic testing-based cardiovascular risk assessment at week 24. The primary endpoint of this study was the plasma LDL-C level at week 24. RESULTS: Fifty eligible patients with clinically diagnosed FH, without a history of CHD, were allocated to the intervention group (n = 24) or the wait-list control group (n = 26). At week 24, the intervention group had a significantly greater reduction in LDL-C levels than the wait-list control group (mean changes, -13.1 mg/dL vs. 6.6 mg/dL; difference, -19.7 mg/dL; 95% confidence interval, -34 to -5.6; p = 0.009). This interventional effect was consistent with FH causative variant carriers but not with non-carriers. CONCLUSIONS: In addition to standard FH care, providing future cardiovascular risk based on genetic testing can further reduce plasma LDL-C levels, particularly among FH causal variant carriers. REGISTRATION: Japan Registry of Clinical Trials (jRCTs04218002). URL: https://jrct.niph.go.jp/latest-detail/jRCTs042180027.

Impact of Healthy Lifestyle in Patients With Familial Hypercholesterolemia.

Background: Pathogenic mutations are associated with poor outcomes in patients with familial hypercholesterolemia (FH). However, data on the effects of a healthy lifestyle on FH phenotypes are limited. Objectives: The authors investigated the interaction between a healthy lifestyle and FH mutation with prognosis in patients with FH. Methods: We investigated the associations of the interaction between genotypes and lifestyle, with the occurrence of major adverse cardiac events (MACE), such as cardiovascular-related mortality, myocardial infarction, unstable angina, and coronary artery revascularization, in patients with FH. We assessed their lifestyle based on 4 questionnaires (healthy dietary pattern, regular exercise, not smoking, and absence of obesity). The Cox proportional hazards model was used to assess the risk for MACE. Results: The median follow-up duration was 12.6 (IQR: 9.5-17.9) years. During the follow-up duration, 179 MACE were observed. Independent of classic risk factors, FH mutation and lifestyle score were significantly associated with MACE (HR: 2.73; 95% CI: 1.03-4.43; P = 0.02; and HR: 0.69, 95% CI: 0.40-0.98, P = 0.033, respectively). The estimated risk of coronary artery disease by 75 years of age varied according to lifestyle, ranging from 21.0% among noncarriers with a favorable lifestyle to 32.1% among noncarriers with an unfavorable lifestyle and ranging from 29.0% among carriers with a favorable lifestyle to 55.4% among carriers with an unfavorable lifestyle. Conclusions: A healthy lifestyle was associated with reduced risk for MACE among patients with FH with or without genetic diagnosis.

Attainment of the low-density lipoprotein cholesterol treatment target and prognosis of heterozygous familial hypercholesterolemia.

BACKGROUND AND AIMS: No previous study has investigated the association between attainment of low-density lipoprotein (LDL) cholesterol treatment target and better prognosis in patients with familial hypercholesterolemia (FH). The current research aimed to examine the association between attainment of LDL cholesterol treatment target and major adverse cardiac events (MACEs) in patients with FH to validate the current LDL cholesterol treatment targets in primary (<100 mg/dL) and secondary (<70 mg/dL) prevention settings. METHODS: The data of patients with FH who were admitted to Kanazawa University Hospital between 2000 and 2020 and who were followed-up were retrospectively reviewed. The number of MACEs, including mortality associated with cardiovascular disease, unstable angina, and myocardial infarction per 1000 person-years, was calculated for each stratum for the attainment of LDL cholesterol target. RESULTS: The median follow-up duration was 12.6 years. In total, 132 MACEs were recorded during the follow-up period. The numbers of patients who attained the LDL cholesterol target in the primary and secondary prevention groups were 228 (31.9%) and 40 (11.9%), respectively. The event rates per 1000 person-years for LDL cholesterol levels of <100 and ≥100 mg/dL in the primary prevention group were 2.6 and 4.4, respectively. The event rates per 1000 person-years for LDL cholesterol levels of <70 and ≥70 mg/dL in the secondary prevention group were 15.3 and 27.5, respectively. CONCLUSIONS: Attainment of the LDL cholesterol target is associated with better prognosis in patients with FH. However, the attainment rate is currently inadequate among Japanese.

Impact of High-Density Lipoprotein Function, Rather Than High-Density Lipoprotein Cholesterol Level, on Cardiovascular Disease Among Patients With Familial Hypercholesterolemia.

BACKGROUND: Recently, the function of high-density lipoprotein (HDL), rather than the HDL cholesterol (HDL-C) level, has been attracting more attention in risk prediction for coronary artery disease (CAD).Methods and Results: Patients with clinically diagnosed familial hypercholesterolemia (FH; n=108; male/female, 51/57) were assessed cross-sectionally. Serum cholesterol uptake capacity (CUC) levels were determined using our original cell-free assay. Linear regression was used to determine associations between CUC and clinical variables, including low-density lipoprotein cholesterol and the carotid plaque score. Multivariable logistic regression analysis was used to test factors associated with the presence of CAD. Among the 108 FH patients, 30 had CAD. CUC levels were significantly lower among patients with than without CAD (median [interquartile range] 119 [92-139] vs. 142 [121-165] arbitrary units [AU]; P=0.0004). In addition, CUC was significantly lower in patients with Achilles tendon thickness ≥9.0 mm than in those without Achilles tendon thickening (133 [110-157] vs. 142 [123-174] AU; P=0.047). Serum CUC levels were negatively correlated with the carotid plaque score (Spearman's r=0.37; P=0.00018). Serum CUC levels were significantly associated with CAD, after adjusting for other clinical variables (odds ratio=0.86, 95% CI=0.76-0.96, P=0.033), whereas HDL-C was not. CONCLUSIONS: HDL function, assessed by serum CUC level, rather than HDL-C level, adds risk stratification information among FH patients.

Impact of variants of uncertain significance of LDL receptor on phenotypes of familial hypercholesterolemia.

BACKGROUND: Data on the effect of variants of uncertain significance (VUS) of LDL receptor (LDLR) on familial hypercholesterolemia (FH) phenotype is limited. OBJECTIVE: To investigate the associations between genotypes and phenotypes, including low-density lipoprotein (LDL) cholesterol level and occurrence of major adverse cardiac events (MACEs), in FH patients (N = 1050, male/female = 490/560). METHODS: We retrospectively assessed the data of patients with FH admitted at Kanazawa University Hospital between 1990 and 2020. Based on genotype, the patients were divided into patients without variants, with VUS of LDLR, and with pathogenic variants. Cox proportional hazard model was used to identify the factors associated with MACEs. RESULTS: The median follow-up duration was 12.6 years (interquartile range: 9.5-17.9 years). Altogether, 777 patients had FH mutation and 273 had pathogenic mutation, with 92 having VUS. Over the follow-up duration, 175 MACEs were observed. LDL cholesterol level was found to be significantly higher in patients with pathogenic variants (251 mg/dL) than in patients with VUS (225 mg/dL) and without variants (203 mg/dL). Pathogenic variants and VUS are significantly associated with MACEs (hazard ratio [HR] = 1.52, 95% confidence interval [CI] = 1.02-2.02, P = 0.033 and HR = 3.18, 95% CI = 2.00-4.36, P = 1.9 × 10-5, relative to patients without any variants, respectively), independent of classical risk factors. CONCLUSION: VUS of LDLR was significantly associated with poor outcomes in FH patients. Genetic testing is useful for the diagnosis and risk stratification of FH patients.

Whole Exome Sequencing Insufficient for a Definitive Diagnosis of a Patient with Compound Heterozygous Familial Hypercholesterolemia.

Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disorder, and a genetic analysis is important to make a definitive diagnosis. A comprehensive genetic analysis using next generation sequencing (NGS) and whole exome sequencing (WES) is feasible. However, the application of NGS in the assessment of genomic structural variations is generally limited, and a substantial number of control samples are needed for such assessments. Thus, NGS alone is unlikely to detect genomic structural variations in a "singleton." We present the case of a patient with compound HeFH (heterozygous FH), whose causative mutations in the LDLR gene could not be identified by WES, necessitating the application of the multiplex ligation-dependent probe amplification (MLPA) technique.

Achilles Tendon Thickness Assessed by X-ray Predicting a Pathogenic Mutation in Familial Hypercholesterolemia Gene.

AIM: The 2017 Japan Atherosclerosis Society (JAS) familial hypercholesterolemia (FH) criteria adopt a cut-off value of ≥ 9 mm of Achilles tendon thickness (ATT) detected by X-ray as one of the three key items. This threshold was determined based on an old data evaluating the ATT of 36 non-FH individuals that was published in 1977. Although the specificity of these clinical criteria is extremely high due to a strict threshold, there are a significant number of patients with FH whose ATT ＜9 mm. We aimed to determine a cut-off value of ATT detected by X-ray to differentiate FH and non-FH based on genetic diagnosis. METHODS: The individuals (male/female=486/501) with full assessments of genetic analyses for FH-genes (LDLR and PCSK9), serum lipids, and ATT detected by X-ray at the Kanazawa University Hospital and National Cerebral and Cardiovascular Center Research Institute were included in this study. Receiver operating characteristic (ROC) analyses were conducted to determine a better cut-off value of ATT that predicts the pathogenic mutation of FH. RESULTS: The ROC analyses revealed that the best cut-off values of ATT are 7.6 mm for male and 7.0 mm for female, with the sensitivities/specificities of 0.83/0.83 for male and 0.86/0.85 for female, respectively. If the thresholds of ATT of 8.0/7.5 mm and 7.5/7.0 mm were applied to the diagnosis of male/female FH, the sensitivities/specificities predicting the pathogenic mutation of FH by the 2017 JAS FH clinical criteria would be 0.82/0.90 and 0.85/0.88, respectively. CONCLUSIONS: These results suggest that the cut-off value of ATT detected by X-ray is obviously lower than 9.0 mm, which was adopted by the 2017 JAS FH clinical criteria.

Genetic mutations, regression of Achilles tendon thickness, and cardiovascular events among patients with familial hypercholesterolemia.

BACKGROUND AND AIMS: Achilles tendon thickness (ATT) can be regressed through LDL-lowering in patients with familial hypercholesterolemia (FH). We aimed to determine factors associated with regression of ATT and its role in development of major adverse cardiovascular events (MACE). METHODS: Patients with clinically diagnosed FH (N = 1,050, male/female = 490/560) were retrospectively assessed. FH-related gene mutations and ATT data using X-ray were collected. Multivariable linear regression analysis was exploited to test the factors associated with deterioration of ATT. Cox proportional hazards models were used to assess factors associated with MACE, including cardiovascular death and acute coronary events. RESULTS: The median follow-up period was 12.6 years. FH-linked mutations were identified in 777 patients. During the follow-up period, 113 MACEs were observed, and median ATT was regressed from 8.7 to 8.5 mm. We found that there was more significant positive correlation between cholesterol-year score and ATT among patients with FH-related gene mutation (p < 2.2 × 10-16; Spearman's r = 0.42). Multivariable linear regression analyses revealed that age (standardized coefficients [SCs] = 0.307, 95% confidence interval [CI] = 0.241-0.373), hypertension (SCs = 0.069, 95%CI = 0.001-0.138), and diabetes (SCs = 0.059, 95% CI = 0.003-0.115) were positively correlated with changes in ATT (progression). Baseline ATT (SCs = -0.474, 95%CI = -0.535-0.413) and FH-related mutations (SCs = -0.058, 95%CI = -0.091-0.024) were negatively correlated with changes in ATT (regression). Considering this confounding factors, regression of ATT was significantly associated with reduced MACE (hazard ratio [HR] = 0.67, 95%CI = 0.51-0.89, per 1.0 mm). CONCLUSIONS: Assessed ATT condition and presence of FH-linked gene mutations represent diagnostic values and risk stratification information among patients with FH.

Familial Hypercholesterolemia in Patients with Acute Coronary Syndrome: Genetic Insights from EXPLORE-J.

AIM: Genetic testing can provide a definitive diagnosis of familial hypercholesterolemia (FH). However, accessibility of genetic testing may be limited in certain countries where it is not considered "standard of care," including Japan. In addition, mutations responsible for FH cannot be identified in approximately 30% of patients. METHODS: EXPLORE-J is a multicenter, prospective, observational study of patients presenting with acute coronary syndrome (ACS). The genetic data were analyzed and adjudicated as pathogenic, indeterminate, or nondetectable pathogenic variant. RESULTS: Of 1,944 patients, 431 underwent genetic screening. Overall, most patients had nonpathogenic variants of LDLR, LDLRAP1, or PCSK9 (n=396, 91.9%). Of the 25 (5.8%) patients with pathogenic variants, variants of the LDLR gene and the PCSK9 gene were seen in 10 and 15 patients, respectively. Indeterminate variants were observed in 10 (2.3%) patients. Of the 431 patients, eight (1.9%) met the criteria for a diagnosis of FH using the Japanese Atherosclerosis Society (JAS) 2017 guidelines. When genetic data were incorporated, 33 (7.7%) patients met the JAS guidelines. No patients with FH pathogenic variants satisfied the JAS clinical criteria for a diagnosis of FH. CONCLUSIONS: The results revealed a higher prevalence of genetic mutations of FH among Japanese patients with ACS and a low sensitivity of the FH diagnostic criteria of the JAS 2017 guidelines. These findings highlight the difficulties of FH diagnosis in patients with ACS in the acute phase and suggest the importance of genetic testing and family history.

Effect of Cumulative Exposure to Low-Density Lipoprotein-Cholesterol on Cardiovascular Events in Patients With Familial Hypercholesterolemia.

BACKGROUND: Recent studies suggest that cumulative exposure to low-density lipoprotein-cholesterol (LDL-C) leads to the development of atherosclerotic cardiovascular disease (ASCVD). However, few studies have investigated whether this link extends to individuals with familial hypercholesterolemia (FH), a relevant patient population.Methods and Results:We retrospectively investigated the health records of 1,050 patients with clinical FH diagnosis between April 1990 and March 2019. We used Cox proportional hazards models adjusted for established ASCVD risk factors to assess the association between cholesterol-year-score and major adverse cardiovascular events (MACEs), including death from any cause or hospitalization due to ASCVD events. Cholesterol-year-score was calculated as LDL-C max × [age at diagnosis/statin initiation] + LDL-C at inclusion × [age at inclusion - age at diagnosis/statin initiation]. The median follow-up period for MACE evaluation was 12.3 (interquartile range, 9.1-17.5) years, and 177 patients experienced MACEs during the observation period. Cholesterol-year-score was significantly associated with MACEs (hazard ratio, 1.35; 95% confidence interval, 1.07-1.53; P=0.0034, per 1,000 mg-year/dL), independent of other traditional risk factors including age and LDL-C, based on cross-sectional assessment. Cholesterol-year-score improved the discrimination ability of other traditional risk factors for ASCVD events (C-index, 0.901 vs. 0.889; P=0.00473). CONCLUSIONS: Cumulative LDL-C exposure was strongly associated with MACEs in Japanese patients with FH, warranting early diagnosis and treatment initiation in these patients.

Homozygous Familial Hypercholesterolemia.

Familial hypercholesterolemia (FH) is an inherited disorder with retarded clearance of plasma LDL caused by mutations of the genes involved in the LDL receptor-mediated pathway and most of them exhibit autosomal dominant inheritance. Homozygotes of FH (HoFH) may have plasma LDL-C levels, which are at least twice as high as those of heterozygous FH (HeFH) and therefore four times higher than normal levels. Prevalence of HoFH had been estimated as 1 in 1,000,000 before but more recent genetic analysis surveys predict 1 in 170,000 to 300,000. Since LDL receptor activity is severely impaired, HoFH patients do not or very poorly respond to medications to enhance activity, such as statins, and have a poorer prognosis compared to HeFH. HoFH should therefore be clinically distinguished from HeFH. Thorough family studies and genetic analysis are recommended for their accurate diagnosis.Fatal cardiovascular complications could develop even in the first decade of life for HoFH, so aggressive lipid-lowering therapy should be initiated as early as possible. Direct removal of plasma LDL by lipoprotein apheresis has been the principal measure for these patients. However, this treatment alone may not achieve stable LDL-C target levels and combination with drugs should be considered. The lipid-lowering effects of statins and PCSK9 inhibitors substantially vary depending on the remaining LDL receptor activity of individual patients. On the other hand, the action an MTP inhibitor is independent of LDL receptor activity, and it is effective in most HoFH cases.This review summarizes the key clinical issues of HoFH as well as insurance coverage available under the Japanese public healthcare system.

Prognostic impact of cascade screening for familial hypercholesterolemia on cardiovascular events.

BACKGROUND: Familial hypercholesterolemia (FH) is an autosomal dominant disorder mainly caused by mutations in the low-density lipoprotein (LDL) receptor or associated genes, resulting in elevated serum cholesterol levels and an increased risk of premature atherosclerotic cardiovascular disease (ASCVD). OBJECTIVE: We aimed to evaluate the prognostic impact of cascade screening for FH. METHODS: We retrospectively investigated the health records of 1050 patients with clinically diagnosed FH, including probands and their relatives who were cascade-screened, who were referred to our institute. We used Cox models that were adjusted for established ASCVD risk factors to assess the association between cascade screening and major adverse cardiac events (MACE). The median period of follow-up evaluating MACE was 12.3 years (interquartile ranges [IQR] = 9.1-17.5 years), and MACE included death associated with ASCVD, or acute coronary syndrome. RESULTS: During the observation period, 113 participants experienced MACE. The mean age of patients identified through cascade screening was 18-years younger than that of the probands (38.7 yr vs. 57.0 yr, P < 0.0001), with a lower proportion of ASCVD risk factors. Interestingly, patients identified through cascade screening under milder lipid-lowering therapies were at reduced risk for MACE (hazard ratio [HR] = 0.67; 95%CI = 0.44 to 0.90; P = 0.0044) when compared with the probands, even after adjusting for those known risk factors, including age, and prior ASCVD. CONCLUSIONS: The identification of patients with FH via cascade screening appeared to result in better prognosis.

Clinical Diagnostic Criteria of Familial Hypercholesterolemia　- A Comparison of the Japan Atherosclerosis Society and Dutch Lipid Clinic Network Criteria.

BACKGROUND: This study is aimed to compare the efficacy of the 2017 Japan Atherosclerosis Society (JAS) familial hypercholesterolemia (FH) criteria, which focuses on only 3 essential clinical manifestations, with that of Dutch Lipid Clinic Network (DLCN) FH criteria, which adopts a scoring system of multiple elements.Methods and Results:A total of 680 Japanese dyslipidemic participants (51% men) were enrolled between 2006 and 2018, all of whom had full evaluations of low-density lipoprotein (LDL) cholesterol, Achilles tendon X-rays, family history records, and genetic analysis of FH-associated genes (LDLR,APOB, andPCSK9). Predictive values for the existence of FH mutations by both clinical criteria were evaluated. Overall, 173 FH patients were clinically diagnosed by using the 2017 JAS criteria and 100, 57, 156, and 367 subjects were also diagnosed as having definite, probable, possible, and unlikely FH by the DLCN FH criteria, respectively. The positive and negative likelihood ratio predicting the presence of FH mutations by using the 2017 JAS FH criteria were 19.8 and 0.143, respectively; whereas, using the DLCN criteria of definite, probable, and possible FH, the ratios were 29.2 and 0.489, 9.70 and 0.332, and 3.43 and 0.040, respectively. CONCLUSIONS: Among Japanese patients, the JAS 2017 FH criteria is considered superior to diagnose FH mutation-positive patients and simultaneously rule out FH mutation-negative patients compared with the DLCN FH criteria.

A case with familial hypercholesterolemia complicated with severe systemic atherosclerosis intensively treated for more than 30 years.

We present a case of a Japanese patient with familial hypercholesterolemia (FH) caused by a low-density lipoprotein (LDL) receptor gene mutation. A 47-year-old female was referred to our hospital due to her systemic xanthomatosis associated with elevated LDL-cholesterolemia (292 mg/dl). She was diagnosed with heterozygous FH, and started to be treated with simvastatin 10 mg. During her clinical course, she underwent percutaneous coronary intervention (PCI) (at 69 years), coronary artery bypass grafting (CABG) twice (at 62 years, and 75 years), femoral popliteal bypass surgery (at 67 years), together with intensification of lipid-lowering therapies, including proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor. She was admitted to our hospital due to dyspnea on effort, caused by severe aortic valve stenosis as well as sick sinus syndrome at the age of 78 years. transcatheter aortic valve implantation (TAVI) using balloon expandable valve was successfully performed after DDD pacemaker implantation. She was discharged from our hospital without any symptoms. During more than 30 years of treatment period in our institute, we have introduced the latest therapeutic strategies, and treated her intensively. We are proud that we can save life even in this severe case through multiple strategies developed over the decades; however, this case clearly suggests that lipid-lowering therapies should be started much earlier in patients with FH. .

Hokuriku-plus familial hypercholesterolaemia registry study: rationale and study design.

INTRODUCTION: Familial hypercholesterolaemia (FH) is an autosomal-dominant inherited genetic disease. It carries an extremely high cardiovascular risk associated with significantly elevated low-density lipoprotein (LDL) cholesterol. The diagnostic rate of this disease in some European nations is quite high, due to the presence of multiple prospective registries. On the other hand, few data-and in particular multicentre data-exist regarding this issue among Japanese subjects. Therefore, this study intends to assemble a multicentre registry that aims to comprehensively assess cardiovascular risk among Japanese FH patients while taking into account their genetic backgrounds. METHODS AND ANALYSIS: The Hokuriku-plus FH registry is a prospective, observational, multicentre cohort study, enrolling consecutive FH patients who fulfil the clinical criteria of FH in Japan from 37 participating hospitals mostly in Hokuriku region of Japan from April 2020 to March 2024. A total of 1000 patients will be enrolled into the study, and we plan to follow-up participants over 5 years. We will collect clinical parameters, including lipids, physical findings, genetic backgrounds and clinical events covering atherosclerotic and other important events, such as malignancies. The primary endpoint of this study is new atherosclerotic cardiovascular disease (ASCVD) events. The secondary endpoints are as follows: LDL cholesterol, secondary ASCVD events and the occurrence of other diseases including hypertension, diabetes and malignancies. ETHICS AND DISSEMINATION: This study is being conducted in compliance with the Declaration of Helsinki, the Ethical Guidelines for Medical and Health Research Involving Human Subjects, and all other applicable laws and guidelines in Japan. This study protocol has been approved by the Institutional Review Board at Kanazawa University. We will disseminate the final results at international conferences and in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: UMIN000038210.

A catalog of the pathogenic mutations of LDL receptor gene in Japanese familial hypercholesterolemia.

BACKGROUND: Little data exist on the pathogenic mutations of LDL receptor in Japanese familial hypercholesterolemia (FH). OBJECTIVE: We aimed to catalog the pathogenic mutations of LDL receptor gene in the 2 major Japanese FH-care centers (Kanazawa University and National Cerebral and Cardiovascular Center Research Institute), where genetic testing of FH has been performed centrally on requests from institutes all over Japan during more than past 2 decades. METHODS: 796 FH subjects from 472 families who had nonsynonymous mutations in LDL receptor gene were included in this study. Genetic mutations were analyzed for mutations by Sanger sequencing as well as by multiplex ligation probe dependent amplification technique for large rearrangements. Pathogenic mutations were defined either as 1) protein truncated variants, 2) registered as pathogenic in ClinVar, or Human Gene Mutation Database (HGMD), or meet the criteria of American College of Medical Genetics and Genomics guideline, or 3) CADD score > 10. RESULTS: We found 138 different mutations. Among them, 132 mutations were considered as pathogenic, including 19 large rearrangement mutations. However, 6 missense mutations were classified as variants of unknown significance. A single mutation accounted for as much as 41% of the FH subjects recruited from Kanazawa University mainly due to founder gene effect, whereas many singleton mutations were found from National Cerebral and Cardiovascular Center Research Institute located in Osaka. CONCLUSIONS: We provided the largest catalog of pathogenic mutations of LDL receptor gene in Japanese FH. This could aid to determine the pathogenicity of the LDL receptor genetic mutations not only in Japanese but also in other ethnicities.