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PURPOSE OF REVIEW: A polygenic risk score (PRS) is a measure of genetic liability to a disease and is typically normally distributed in a population. Individuals in the upper tail of this distribution often have relative risk equivalent to that of monogenic form of the disease. The majority of currently available PRSs for coronary heart disease (CHD) have been generated from cohorts of European ancestry (EUR) and vary in their applicability to other ancestry groups. In this report, we review the performance of PRSs for CHD across different ancestries and efforts to reduce variability in performance including novel population and statistical genetics approaches. RECENT FINDINGS: PRSs for CHD perform robustly in EUR populations but lag in performance in non-EUR groups, particularly individuals of African ancestry. Several large consortia have been established to enable genomic studies in diverse ancestry groups and develop methods to improve PRS performance in multi-ancestry contexts as well as admixed individuals. These include fine-mapping to ascertain causal variants, trans ancestry meta-analyses, and ancestry deconvolution in admixed individuals. SUMMARY: PRSs are being used in the clinical setting but enthusiasm has been tempered by the variable performance in non-EUR ancestry groups. Increasing diversity in genomic association studies and continued innovation in methodological approaches are needed to improve PRS performance in non-EUR individuals for equitable implementation of genomic medicine.

Background: The Clinical Genome Resource Consortium (ClinGen) recommends MaxEntScan (MES) model to predict the effects of LDLR splice variants. We developed “MaxSpliZer”, a software tool to automate the implementation of MES, and validated it using ClinVar and UK-Biobank (UKBB) data. Method: We tested concordance of MaxSpliZer predictions with ClinVar classifications of benign/likely benign (B/LB) and pathogenic/likely pathogenic (P/LP) for LDLR variants with potential effect on splicing. We also annotated LDLR splice variants in 200,618 UKBB participants, categorizing them using MaxSpliZer as deleterious (n=90) and non-deleterious (n=7,404). Low-density lipoprotein cholesterol (LDL-C) levels were compared in these two groups after adjustment for lipid-lowering medication use. Results: MaxSpliZer prediction was concordant with the ClinVar classification in 128 of 138 P/LP variants (sensitivity 93%) and 432 of 436 B/LB variants (specificity 99%). In the UKBB, splice variants predicted as deleterious by MaxSpliZer had higher LDL-C than non-deleterious splice variants (158.7±47.4 vs. 146.0±34.8mg/dL, p-value = 0.014). Compared to manual curation time of 12±7 min per variant, MaxSpliZer took 0.52±0.11 min for single entries and 1.5 s per variant for biobank-scale data. Conclusion: MaxSpliZer, a software tool that implements MES based on the ClinGen guideline, can accurately classify LDLR splice variants in a rapid automated fashion.

Supplemental Digital Content is available in the text., Background: Abdominal aortic aneurysm (AAA) is an important cause of cardiovascular mortality; however, its genetic determinants remain incompletely defined. In total, 10 previously identified risk loci explain a small fraction of AAA heritability. Methods: We performed a genome-wide association study in the Million Veteran Program testing ≈18 million DNA sequence variants with AAA (7642 cases and 172 172 controls) in veterans of European ancestry with independent replication in up to 4972 cases and 99 858 controls. We then used mendelian randomization to examine the causal effects of blood pressure on AAA. We examined the association of AAA risk variants with aneurysms in the lower extremity, cerebral, and iliac arterial beds, and derived a genome-wide polygenic risk score (PRS) to identify a subset of the population at greater risk for disease. Results: Through a genome-wide association study, we identified 14 novel loci, bringing the total number of known significant AAA loci to 24. In our mendelian randomization analysis, we demonstrate that a genetic increase of 10 mm Hg in diastolic blood pressure (odds ratio, 1.43 [95% CI, 1.24–1.66]; P=1.6×10−6), as opposed to systolic blood pressure (odds ratio, 1.06 [95% CI, 0.97–1.15]; P=0.2), likely has a causal relationship with AAA development. We observed that 19 of 24 AAA risk variants associate with aneurysms in at least 1 other vascular territory. A 29-variant PRS was strongly associated with AAA (odds ratioPRS, 1.26 [95% CI, 1.18–1.36]; PPRS=2.7×10−11 per SD increase in PRS), independent of family history and smoking risk factors (odds ratioPRS+family history+smoking, 1.24 [95% CI, 1.14–1.35]; PPRS=1.27×10−6). Using this PRS, we identified a subset of the population with AAA prevalence greater than that observed in screening trials informing current guidelines. Conclusions: We identify novel AAA genetic associations with therapeutic implications and identify a subset of the population at significantly increased genetic risk of AAA independent of family history. Our data suggest that extending current screening guidelines to include testing to identify those with high polygenic AAA risk, once the cost of genotyping becomes comparable with that of screening ultrasound, would significantly increase the yield of current screening at reasonable cost.

Introduction: Clonal hematopoiesis of indeterminate potential (CHIP) refers to the formation of genetically distinct subpopulations of blood cells due to somatic mutations. CHIP is associated with a variety of adverse outcomes, including hematological cancers, cardiovascular disease, and death. We sought to investigate the association of CHIP with incident venous thromboembolism (VTE). Methods: We analyzed exome sequence data from 200,628 individuals in the UK Biobank cohort using Mutect2 to identify a prespecified list of somatic mutations in DNMT3A, TET2, and ASXL1, which are known genetic drivers of CHIP. CHIP was defined as harboring a somatic mutation at a variant allele fraction (VAF) ≥10% and individuals with VAF Results: Among 200,628 individuals, we identified 3,885 individuals with CHIP at baseline and 748 incident VTE events during a median follow-up of 9.2 years. In 748 incident cases and 5984 matched controls, CHIP was associated with increased risk of incident VTE independent of conventional risk factors for VTE, namely, age, sex, BMI, smoking, and history of malignancy (incidence rate ratio [95% confidence interval]; 1.60 [1.04-2.46], p=0.032). When we restricted the cases to individuals with incident pulmonary embolism (n=441), we observed a stronger association with CHIP (1.80 [1.08-3.05], p=0.025). Conclusions: CHIP is associated with increased risk of VTE independent of history of malignancy and other conventional risk factors. The pathophysiological basis for this association needs further investigation.

Introduction: The potential use of polygenic risk scores (PRSs) in clinical practice is tempered by concern about their portability among diverse populations. To prevent disparities in genomic medicine, there is an urgent need to conduct genome-wide association studies in non-European ancestry cohorts. Methods: We conducted whole genome sequencing (WGS) with 30x coverage on coronary heart disease patients (n=1,067, mean age ± SD = 59.96 years ± 10.99; 70.32% males) and controls (n=6,170, mean age ± SD = 40.02 years ± 12.56; 43.45% males) in a Middle Eastern cohort to compare the performance of available PRSs for CHD (LDpred, metaGRS, lassosum, and P+T) and identify common variants associated with CHD (via generalized linear mixed models). Results: Excepting lassosum, all PRSs performed well. LDpred and metaGRS performed similarly (AUC= ~0.685) and outperformed P+T (AUC=0.667). Based on the OR per 1 SD increase (OR 1sd ), P+T (OR 1sd =1.85 [1.69-2.02], P =3.69x10 -41 ) outperformed other PRSs (OR 1sd =1.61 [1.48-1.74], P =3.02x10 -31 for LDpred and OR 1sd =1.61 [1.49-1.75], P =9.47x10 -31 for metaGRS). After binning PRSs into 10 deciles, the odds of CHD in the top decile compared to all others was highest for metaGRS (3.87 [3.07-4.88]) and LDpred (3.45 [2.74-4.341]). Thirty-two known GWAS loci (e.g., ABCG8 , CELSR2 , and SLC22A4 ) were replicated in our analysis with P P -6 ) with relevant biological function were identified (e.g., CORO7 , RBM47 , and PDE4D ). The well-established 9p21 locus was not replicated. Conclusions: Genome-wide PRSs derived from European ancestry cohorts performed well in a Middle Eastern cohort. Further studies are needed to develop and validate an ancestry specific PRS and to confirm the suggestive loci/genes.

Introduction: The prevalence of atrial fibrillation (AF) increases with age and inflammation plays a key pathophysiologic role. Somatic mosaicism increases with age and promotes inflammation. Therefore, we investigated whether Clonal Hematopoiesis of Indeterminate Potential (CHIP) is a risk factor for incident AF. Methods: We assessed exome sequence (ES) data from 200,628 participants in the UK biobank. Using the Genome Analysis Toolkit pipeline, we ascertained a predefined list of CHIP mutations in DNMT3A , TET2 , and ASXL1 . CHIP was defined as variant allele frequency (VAF) >10% and those with VAF Results: Of 200,628 participants, 3885 (1.9%) had CHIP. The number of participants with mutations in DNMT3A , TET2 , and ASXL1 was 2512, 1065, and 439, respectively. During a median follow-up of 9 years, 4,676 incident AF and 3,584 incident lone AF occurred. CHIP was an independent risk factor for developing incident AF and also for developing lone AF. CHIP in TET2 and ASXL1 but not DNMT3A was associated with AF ( Table 1 ). Conclusions: The presence of CHIP involving TET2 and ASXL1 is associated with an increased risk of incident AF including the subset with lone AF. Our findings reveal somatic mosaicism in blood cells to be a novel risk factor for AF.

Introduction: We aimed to identify and characterize carotid artery stenosis (CAS), defined as ≥40% stenosis in the internal carotid artery (ICA) or the common carotid artery (CCA), among participants of the Mayo Vascular Disease Biorepository (VDB, n = 11,814). Hypothesis: A string-based text processing (TP) tool coded in R can analyze radiology text reports to ascertain and characterize CAS. Methods: After importing a radiology report into R, it was segmented for analysis and each segment was tested for 22 unique features. The TP tool was able to i) identify stenosis in the ICA or the CCA while excluding stenosis of vertebral arteries, subclavian arteries, or external carotid arteries, ii) recognize both quantitative and qualitative descriptions of CAS, iii) interpret numerical expressions by considering the surrounding text, iv) detect negations, and v) ascertain previous revascularization procedures if mentioned in the text. We manually ascertained CAS and characterized it in 800 randomly selected radiology reports to assess the performance of the TP tool in terms of precision, recall, and F-score. Results: We retrieved 21,651 imaging reports for 6,342 unique patients including 20,461 ultrasonography reports, 812 magnetic resonance imaging reports, 357 computed tomography scan reports, and 21interventional radiology reports. The performance of TP is outlined in Table 1 . Conclusion: We demonstrate that a string-based TP tool coded in R is efficient and accurate in identifying and characterizing CAS from carotid radiology reports. The tool does not require natural language processing and could be used in a wide range of settings for genetic and biomarker studies.

Background Hypertriglyceridemia is associated with increased risk of coronary heart disease but the association is often attributed to concomitant metabolic abnormalities. We investigated the epidemiology of primary isolated hypertriglyceridemia (PIH) and associated cardiovascular risk in a population‐based setting. Methods and Results We identified adults with at least one triglyceride level ≥500 mg/dL between 1998 and 2015 in Olmsted County, Minnesota. We also identified age‐ and sex‐matched controls with triglyceride levels P = 0.022). There was no statistically significant association between PIH and cerebrovascular disease (HR, 1.06; 95% CI, 0.65‐1.73, P = 0.813), peripheral artery disease (HR, 1.27; 95% CI, 0.43‐3.75; P = 0.668), or the composite end point of all 3 (HR, 1.28; 95% CI, 0.92‐1.80; P =0.148) in adjusted models. Conclusions PIH was associated with incident coronary heart disease events (although there was attenuation after adjustment for conventional risk factors), supporting a causal role for triglycerides in coronary heart disease. The condition is relatively prevalent but awareness and control are low.

There are limited data from the US on outcomes of patients in specialty care for familial hypercholesterolemia (FH).CASCADE FH Registry data were analyzed to assess longitudinal changes in medication usage, in low density lipoprotein cholesterol (LDL-C) levels, and the rate of major adverse cardiovascular events (MACE (myocardial infarction, coronary revascularization, stroke or transient ischemic attack) in adults with FH followed in US specialty clinics.The cohort consisted of 1900 individuals (61% women, 87% Caucasian), with mean age of 56 ± 15 years, 37% prevalence of ASCVD at enrollment, mean pretreatment LDL-C 249 ± 68 mg/dl, mean enrollment LDL-C 145 mg/dl and 93% taking lipid lowering therapy. Over follow up of 20 ± 11 months, lipid lowering therapy use increased (mean decrease in LDL-C of 32 mg/dl (p0.001)). Only 48% of participants achieved LDL-C100 mg/dl and 22% achieved LDL-C70 mg/dl; ASCVD at enrollment was associated with greater likelihood of goal achievement. MACE event rates were almost 6 times higher among patients with prior ASCVD compared to those without (4.6 vs 0.8/100 patient years). Also associated with incident MACE were markers of FH severity and conventional ASCVD risk factors.With care in FH specialized clinics, LDL-C decreased, but LDL-C persisted100 mg/dl in 52% of patients. High ASCVD event rates suggest that adults with FH warrant designation as having an ASCVD risk equivalent. Earlier and more aggressive therapy of FH is needed to prevent ASCVD events.

Objective— It is unclear to what extent genetic susceptibility variants are shared between peripheral artery disease (PAD) and coronary heart disease (CHD), both manifestations of atherosclerotic vascular disease. We investigated whether common and low-frequency/rare variants in loci associated with CHD are also associated with PAD. Approach and Results— Targeted sequencing of 41 genomic regions associated with CHD in genome-wide association studies was performed in 1749 PAD cases (65±11 years, 61% men) and 1855 controls (60±11 years, 56% men) of European ancestry. PAD cases had a resting/postexercise ankle-brachial index ≤0.9, or history of lower extremity revascularization; controls had no history of PAD. We tested the association of common (defined as minor allele frequency ≥5%) variants with PAD assuming an additive genetic model with adjustment for age and sex. To identify low-frequency/rare variants (minor allele frequency SH2B3, ABO , and ZEB2 to be associated with PAD ( P −5 ). At the gene level, the strongest associations were for LPL and SH2B3 . Conclusions— Targeted sequencing of 41 genomic regions associated with CHD revealed several common variants/genes to be associated with PAD, highlighting the basis of shared genetic susceptibility between CHD and PAD.

Background: \ud Spontaneous coronary artery dissection (SCAD) is an increasingly recognized cause of acute coronary syndromes (ACS) afflicting predominantly younger to middle-aged women. Observational studies have reported a high prevalence of extracoronary vascular anomalies, especially fibromuscular dysplasia (FMD) and a low prevalence of coincidental cases of atherosclerosis. PHACTR1/EDN1 is a genetic risk locus for several vascular diseases, including FMD and coronary artery disease, with the putative causal noncoding variant at the rs9349379 locus acting as a potential enhancer for the endothelin-1 (EDN1) gene.\ud \ud Objectives: \ud This study sought to test the association between the rs9349379 genotype and SCAD.\ud \ud Methods: \ud Results from case control studies from France, United Kingdom, United States, and Australia were analyzed to test the association with SCAD risk, including age at first event, pregnancy-associated SCAD (P-SCAD), and recurrent SCAD.\ud \ud Results: \ud The previously reported risk allele for FMD (rs9349379-A) was associated with a higher risk of SCAD in all studies. In a meta-analysis of 1,055 SCAD patients and 7,190 controls, the odds ratio (OR) was 1.67 (95% confidence interval [CI]: 1.50 to 1.86) per copy of rs9349379-A. In a subset of 491 SCAD patients, the OR estimate was found to be higher for the association with SCAD in patients without FMD (OR: 1.89; 95% CI: 1.53 to 2.33) than in SCAD cases with FMD (OR: 1.60; 95% CI: 1.28 to 1.99). There was no effect of genotype on age at first event, P-SCAD, or recurrence.\ud \ud Conclusions: \ud The first genetic risk factor for SCAD was identified in the largest study conducted to date for this condition. This genetic link may contribute to the clinical overlap between SCAD and FMD.

Background: Sequencing Mendelian arrhythmia genes in individuals without an indication for arrhythmia genetic testing can identify carriers of pathogenic or likely pathogenic (P/LP) variants. However, the extent to which these variants are associated with clinically meaningful phenotypes before or after return of variant results is unclear. In addition, the majority of discovered variants are currently classified as variants of uncertain significance, limiting clinical actionability. Methods: The eMERGE-III study (Electronic Medical Records and Genomics Phase III) is a multicenter prospective cohort that included 21 846 participants without previous indication for cardiac genetic testing. Participants were sequenced for 109 Mendelian disease genes, including 10 linked to arrhythmia syndromes. Variant carriers were assessed with electronic health record–derived phenotypes and follow-up clinical examination. Selected variants of uncertain significance (n=50) were characterized in vitro with automated electrophysiology experiments in HEK293 cells. Results: As previously reported, 3.0% of participants had P/LP variants in the 109 genes. Herein, we report 120 participants (0.6%) with P/LP arrhythmia variants. Compared with noncarriers, arrhythmia P/LP carriers had a significantly higher burden of arrhythmia phenotypes in their electronic health records. Fifty-four participants had variant results returned. Nineteen of these 54 participants had inherited arrhythmia syndrome diagnoses (primarily long-QT syndrome), and 12 of these 19 diagnoses were made only after variant results were returned (0.05%). After in vitro functional evaluation of 50 variants of uncertain significance, we reclassified 11 variants: 3 to likely benign and 8 to P/LP. Conclusions: Genome sequencing in a large population without indication for arrhythmia genetic testing identified phenotype-positive carriers of variants in congenital arrhythmia syndrome disease genes. As the genomes of large numbers of people are sequenced, the disease risk from rare variants in arrhythmia genes can be assessed by integrating genomic screening, electronic health record phenotypes, and in vitro functional studies. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier; NCT03394859.

Background Atherosclerosis in >1 vascular bed (ie, polyvascular disease), often a feature of peripheral artery disease (PAD), is associated with high morbidity and mortality. We sought to identify risk factors for polyvascular involvement in patients with PAD. Methods and Results We performed 2‐sample Mendelian randomization using an inverse‐variance‐weighted approach, to assess 60 exposures including size and lipid content of atherogenic lipoproteins, blood pressure, glycated hemoglobin, and smoking as causal mediators for polyvascular disease in patients with PAD. Genetic instruments for these exposures were obtained from prior genome‐wide association studies. Patients with PAD were from the Mayo Vascular Disease Biorepository, and polyvascular disease (ie, concomitant coronary heart disease, cerebrovascular disease, and/or abdominal aortic aneurysm) was ascertained by validated phenotyping algorithms. Of 3279 patients with PAD, 61% had polyvascular disease. Genetically predicted levels of the lipid content and/or particle measures of very small and small size very low‐density lipoprotein, intermediate‐density lipoprotein, and large low‐density lipoprotein were associated with polyvascular disease: odds ratios (OR) of 1.80 (95% CI, 1.23–2.61), 1.70 (95% CI, 1.17–2.61), and 1.40 (95% CI, 1.09–1.80) per 1 SD increase in genetically determined levels, respectively. Both genetically predicted diastolic and systolic blood pressure were associated with polyvascular disease; OR per 10 mm Hg genetic increase in diastolic and systolic blood pressure were 1.66 (95% CI, 1.19–2.33) and 1.31 (95% CI, 1.07–1.60), respectively. Conclusions Lifetime exposure to increased lipid content and levels of very small and small very low‐density lipoprotein, intermediate‐density lipoprotein, and large low‐density lipoprotein particles as well as elevated blood pressure are associated with polyvascular involvement in patients with PAD. Reduction in levels of such exposures may limit progression of atherosclerosis in patients with PAD.

Genomic data are increasingly being integrated into health care. We propose an outline for structured training in cardiovascular genomics, recognizing the growing need for a cardiovascular genomics subspecialty and cardiovascular subspecialists who incorporate genomics advances to optimize the management of heritable cardiovascular diseases.

Background: The pathophysiology of lipoprotein (a) [Lp(a)] remains obscure. We conducted a phenome wide analysis study (PheWAS) to identify pleiotropic effects of LPA variants. Methods: Among 51,843 European-ancestry participants (age 58±16 years, 54% female) of the electronic MEdical Records and Genomics (eMERGE) network we assessed whether LPA variants exhibited pleiotropic affects through an electronic health record-based PheWAS. We adjusted significant associations by presence of atherosclerotic cardiovascular disease (ASCVD; defined as a composite of coronary heart disease, cerebrovascular disease, and peripheral artery disease) to determine whether those associations were independent of ASCVD. Results: In PheWAS analysis, we tested 864 phecodes with 36 independent LPA variants. We identified 21 significant associations with non-ASCVD phenotypes including heart failure, aortic valve stenosis, and chronic kidney disease of which 14 were replicated across independent cohorts. The strength of associations between the LPA variant rs10455872 and both heart failure and aortic valve stenosis related phecodes were significantly attenuated after adjustment for ASCVD. However, the association with chronic kidney disease phecode remained independent following adjustment for ASCVD without any attenuation in the estimated odds ratio (Table). Conclusions: LPA genetic variants were associated with aortic valve stenosis, heart failure and chronic kidney disease. The observed association of LPA variant rs10455872 with aortic stenosis and heart failure appear to be partially mediated by ASCVD, while the association with chronic kidney disease appears to be independent of ASCVD. Additional studies are needed to elucidate potential mechanisms by which Lp(a) may contribute to the pathogenesis of non-ASCVD disease phenotypes.

Introduction: Functional annotation of rare variants is key to the implementation of genomic medicine. We used molecular dynamics (MD) simulations to assess functional consequences of putative pathogenic variants (PVs) in the low-density lipoprotein receptor gene ( LDLR ). LDLR has a multidomain structure with seven LA repeats and local interactions between these repeats influence ligand binding. However, binding and recycling of the receptor-ligand complex require global changes in conformation. Using MD, we investigated the effects of PVs on long-range dynamics and LDL binding. Methods: An LA 4-6 repeat structure was created from a crystal structure of the extracellular domain (PDB: 1N7D). Structures were solvated with a water box containing TIP3P water molecules and simulated using the AMBER software package with the ff14SB forcefield. The wild type (WT) structure was first relaxed using MD; and subsequently PVs D245Y, F181Y and F181G were modeled. Dynamics were simulated for approximately one microsecond. Values for LDL binding for each PV were obtained from a prior study which used a radioisotope uptake assay. Results: WT domains demonstrated a stable conformation based on root mean square deviation. PVs disrupted the normal distribution in all domains significantly (p < 0.0001), broadening it and introducing multiple peaks. Projection along the top principal components (PCs) showed global destabilization with all PVs. The variant with the greatest impact on LDL binding, F181G, adopted a distinct alternate conformation. Comparison between PV and WT subspaces from PCA correlated with LDL binding (R 2 = 0.99, exponential regression). Structural analysis revealed that the LA5 calcium cage is involved in inter-domain salt bridges, which are disrupted in simulations of PVs. Conclusion: MD simulation of LA4-6 repeats in LDLR suggests PVs alter long-range conformational dynamics, and that such dynamics correlate with LDL binding. The impact of PVs on conformational dynamics and binding may be through disruption of interdomain salt bridges that are mediated by the acidic calcium cage. This study demonstrates the potential utility of MD simulations to functionally characterize LDLR variants.

Familial Hypercholesterolemia (FH): Lipid metabolism autosomal dominant condition; Patients present elevated low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) values since childhood → increased risk of atherosclerotic cardiovascular disease; High heterozygote prevalence (1/250); Homozygous rare (1/1 000 000); Caused by pathogenic variants in LDLR (>90%), APOB (5-10%) and PCSK9 (1-3%) genes. N/A

AIM Osteoprotegerin (OPG) is associated with a poor prognosis in patients with heart failure with preserved ejection fraction (HFpEF). OPG has also been associated with fibrosis and collagen cross-linking, which increase arterial and left ventricle (LV) myocardial stiffness. Little is known about the relation of OPG and LV structure and function in African-Americans who are disproportionately affected by HFpEF. METHODS AND RESULTS Our analysis included 1172 participants with preserved LV ejection fraction (>50%) from the African-American cohort in the Genetic Epidemiology Network of Arteriopathy Study (mean age 63 years, 72% female). We used diastolic wall strain indicator measured by echocardiography to assess LV myocardial stiffness. Diastolic wall strain was calculated as (LV posterior thickness at end-systole - LV posterior thickness at end-diastole)/LV posterior thickness at end-systole. Associations between OPG levels and indices of arterial and LV structure and function were evaluated by using generalized linear mixed models and adjusted for possible confounders. OPG levels were correlated with age, female sex, presence of hypertension and diabetes, and lower estimated glomerular filtration rate (P

Introduction Fibromuscular dysplasia (FMD) is a non-atherosclerotic arteriopathy of unknown etiology, affecting mostly middle-aged women. It is characterized by stenotic lesions of the vascular wall in middle-size arteries, sometimes associated with dissection, aneurysm or tortuosity. Objective We aim at identifying genetic causes of FMD to better understand its mechanism and relation with other vasculopathies. Methods We report results from the first genome-wide association meta-analysis of six studies including 1962 FMD cases and 7100 controls. We integrated genetic association with arterial gene expression using transcriptome-wide association analysis. To identify FMD associated variants located in regulatory elements, we determined open chromatin regions in artery-derived primary cells using ATAC-Seq and estimated heritability and genetic correlation of FMD with other vascular traits and diseases using LD Score regression. Results We found an estimate of SNP-based heritability compatible with a polygenic feature for FMD and report four robustly associated loci (PHACTR1, LRP1, ATP2B1, and LIMA1). Transcriptome-wide association analysis in arteries identified one additional locus (SLC24A3). We found that FMD associated variants were located in arterial-specific regulatory elements. Target genes were broadly involved in mechanisms related to actin cytoskeleton and intracellular calcium homeostasis, central to vascular contraction. We found significant genetic overlap between FMD and blood pressure, although hypertension was not confounding the genetic association with FMD. We also report an important genetic overlap with migraine, intracranial aneurysm, coronary artery disease and LDL cholesterol. Conclusion We identified several loci related to vascular contraction, suggesting that altered vascular tonicity may play a role in the pathogenesis of FMD. We find that FMD is genetically close to several vascular diseases where vascular integrity is impaired.

The cardio-ankle vascular index (CAVI) is a measure of global arterial stiffness. We hypothesized that CAVI is associated with left ventricular (LV) function and geometry in individuals without structural heart disease. We measured CAVI in 600 participants (mean age 60.3±14.6 years, 54% men) without history of atherosclerotic cardiovascular disease who were referred for transthoracic echocardiography. Linear regression analysis was used to assess the association of CAVI with LV function (peak mitral annular systolic s’ and early diastolic velocity e’) and structure (LV mass index (LVMI) and relative wall thickness (RWT)). Older age, male sex, lower body mass index, history of hypertension, diabetes and chronic kidney disease were each associated with a higher CAVI (adjusted R2 = 0.56, all p < 0.01). A higher CAVI was associated with lower s’ and e’, and greater RWT, independent of age, sex, systolic BP and other conventional cardiovascular risk factors (all p < 0.05); a borderline association of higher CAVI with greater LVMI ( p = 0.05) was present. Associations with e’, s’ and RWT were similar in women and men but the association with LVMI was stronger in women than in men ( p for interaction = 0.02, multivariable-adjusted β = 6.92, p < 0.001 in women; p > 0.1 in men). In conclusion, a higher CAVI, a measure of global arterial stiffness, is associated with worse LV systolic function, worse diastolic relaxation, and greater LV RWT in both men and women, and with LVMI in women.

Background— Continued reductions in morbidity and mortality attributable to ischemic heart disease (IHD) require an understanding of the changing epidemiology of this disease. We hypothesized that we could use genetic correlations, which quantify the shared genetic architectures of phenotype pairs and extant risk factors from a historical prospective study to define the risk profile of a contemporary IHD phenotype. Methods and Results— We used 37 phenotypes measured in the ARIC study (Atherosclerosis Risk in Communities; n=7716, European ancestry subjects) and clinical diagnoses from an electronic health record (EHR) data set (n=19 093). All subjects had genome-wide single-nucleotide polymorphism genotyping. We measured pairwise genetic correlations (rG) between the ARIC and EHR phenotypes using linear mixed models. The genetic correlation estimates between the ARIC risk factors and the EHR IHD were modestly linearly correlated with hazards ratio estimates for incident IHD in ARIC (Pearson correlation [ r ]=0.62), indicating that the 2 IHD phenotypes had differing risk profiles. For comparison, this correlation was 0.80 when comparing EHR and ARIC type 2 diabetes mellitus phenotypes. The EHR IHD phenotype was most strongly correlated with ARIC metabolic phenotypes, including total:high-density lipoprotein cholesterol ratio (rG=−0.44, P =0.005), high-density lipoprotein (rG=−0.48, P =0.005), systolic blood pressure (rG=0.44, P =0.02), and triglycerides (rG=0.38, P =0.02). EHR phenotypes related to type 2 diabetes mellitus, atherosclerotic, and hypertensive diseases were also genetically correlated with these ARIC risk factors. Conclusions— The EHR IHD risk profile differed from ARIC and indicates that treatment and prevention efforts in this population should target hypertensive and metabolic disease.

Background Automated individualized risk prediction tools linked to electronic health records (EHRs) are not available for management of patients with peripheral arterial disease. The goal of this study was to create a prognostic tool for patients with peripheral arterial disease using data elements automatically extracted from an EHR to enable real‐time and individualized risk prediction at the point of care. Methods and Results A previously validated phenotyping algorithm was deployed to an EHR linked to the Rochester Epidemiology Project to identify peripheral arterial disease cases from Olmsted County, MN, for the years 1998 to 2011. The study cohort was composed of 1676 patients: 593 patients died over 5‐year follow‐up. The c‐statistic for survival in the overall data set was 0.76 (95% confidence interval [CI], 0.74–0.78), and the c‐statistic across 10 cross‐validation data sets was 0.75 (95% CI, 0.73–0.77). Stratification of cases demonstrated increasing mortality risk by subgroup (low: hazard ratio, 0.35 [95% CI, 0.21–0.58]; intermediate‐high: hazard ratio, 2.98 [95% CI, 2.37–3.74]; high: hazard ratio, 8.44 [95% CI, 6.66–10.70], all P, See Editorial by https://10.1161/JAHA.118.011184

BACKGROUND: Little is known about prevalence, awareness, and control of familial hypercholesterolemia (FH) in the United States. OBJECTIVE: To address these knowledge gaps, we developed an ePhenotyping algorithm for rapid identification of FH in electronic health records (EHRs) and deployed it in the Screening Employees And Residents in the Community for Hypercholesterolemia (SEARCH) study. METHODS: We queried a database of 131,000 individuals seen between 1993 and 2014 in primary care practice to identify 5992 (mean age 52 ± 13 years, 42% men) patients with low-density lipoprotein cholesterol (LDL-C) ≥190 mg/dL, triglycerides

Background— Whether knowledge of genetic risk for coronary heart disease (CHD) affects health-related outcomes is unknown. We investigated whether incorporating a genetic risk score (GRS) in CHD risk estimates lowers low-density lipoprotein cholesterol (LDL-C) levels. Methods and Results— Participants (n=203, 45–65 years of age, at intermediate risk for CHD, and not on statins) were randomly assigned to receive their 10-year probability of CHD based either on a conventional risk score (CRS) or CRS + GRS ( + GRS). Participants in the + GRS group were stratified as having high or average/low GRS. Risk was disclosed by a genetic counselor followed by shared decision making regarding statin therapy with a physician. We compared the primary end point of LDL-C levels at 6 months and assessed whether any differences were attributable to changes in dietary fat intake, physical activity levels, or statin use. Participants (mean age, 59.4±5 years; 48% men; mean 10-year CHD risk, 8.5±4.1%) were allocated to receive either CRS (n=100) or + GRS (n=103). At the end of the study period, the + GRS group had a lower LDL-C than the CRS group (96.5±32.7 versus 105.9±33.3 mg/dL; P =0.04). Participants with high GRS had lower LDL-C levels (92.3±32.9 mg/dL) than CRS participants ( P =0.02) but not participants with low GRS (100.9±32.2 mg/dL; P =0.18). Statins were initiated more often in the + GRS group than in the CRS group (39% versus 22%, P Conclusions— Disclosure of CHD risk estimates that incorporated genetic risk information led to lower LDL-C levels than disclosure of CHD risk based on conventional risk factors alone. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT01936675.

Background: Proteomic approaches allow measurement of thousands of proteins in a single specimen, which can accelerate biomarker discovery. However, applying these technologies to massive biobanks is not currently feasible because of the practical barriers and costs of implementing such assays at scale. To overcome these challenges, we used a “virtual proteomic” approach, linking genetically predicted protein levels to clinical diagnoses in >40 000 individuals. Methods: We used genome-wide association data from the Framingham Heart Study (n=759) to construct genetic predictors for 1129 plasma protein levels. We validated the genetic predictors for 268 proteins and used them to compute predicted protein levels in 41 288 genotyped individuals in the Electronic Medical Records and Genomics (eMERGE) cohort. We tested associations for each predicted protein with 1128 clinical phenotypes. Lead associations were validated with directly measured protein levels and either low-density lipoprotein cholesterol or subclinical atherosclerosis in the MDCS (Malmö Diet and Cancer Study; n=651). Results: In the virtual proteomic analysis in eMERGE, 55 proteins were associated with 89 distinct diagnoses at a false discovery rate qP =0.006) per 1-SD increment in C-type lectin domain family 1 member B and 0.79 (0.66–0.94; P =0.008) per 1-SD increment in platelet-derived growth factor receptor-β. Conclusions: We demonstrate a biomarker discovery paradigm to identify candidate biomarkers of cardiovascular and other diseases.

Background: Coronary heart disease (CHD) is a leading cause of death globally. Although therapy with statins decreases circulating levels of low-density lipoprotein cholesterol and the incidence of CHD, additional events occur despite statin therapy in some individuals. The genetic determinants of this residual cardiovascular risk remain unknown. Methods: We performed a 2-stage genome-wide association study of CHD events during statin therapy. We first identified 3099 cases who experienced CHD events (defined as acute myocardial infarction or the need for coronary revascularization) during statin therapy and 7681 controls without CHD events during comparable intensity and duration of statin therapy from 4 sites in the Electronic Medical Records and Genomics Network. We then sought replication of candidate variants in another 160 cases and 1112 controls from a fifth Electronic Medical Records and Genomics site, which joined the network after the initial genome-wide association study. Finally, we performed a phenome-wide association study for other traits linked to the most significant locus. Results: The meta-analysis identified 7 single nucleotide polymorphisms at a genome-wide level of significance within the LPA/PLG locus associated with CHD events on statin treatment. The most significant association was for an intronic single nucleotide polymorphism within LPA/PLG (rs10455872; minor allele frequency, 0.069; odds ratio, 1.58; 95% confidence interval, 1.35–1.86; P =2.6×10 − 10 ). In the replication cohort, rs10455872 was also associated with CHD events (odds ratio, 1.71; 95% confidence interval, 1.14–2.57; P =0.009). The association of this single nucleotide polymorphism with CHD events was independent of statin-induced change in low-density lipoprotein cholesterol (odds ratio, 1.62; 95% confidence interval, 1.17–2.24; P =0.004) and persisted in individuals with low-density lipoprotein cholesterol ≤70 mg/dL (odds ratio, 2.43; 95% confidence interval, 1.18–4.75; P =0.015). A phenome-wide association study supported the effect of this region on coronary heart disease and did not identify noncardiovascular phenotypes. Conclusions: Genetic variations at the LPA locus are associated with CHD events during statin therapy independently of the extent of low-density lipoprotein cholesterol lowering. This finding provides support for exploring strategies targeting circulating concentrations of lipoprotein(a) to reduce CHD events in patients receiving statins.

We investigated whether family history (FHx) of atherosclerotic cardiovascular disease (ASCVD) was associated with presence of abdominal aortic aneurysm (AAA). The study cohort comprised of 696 patients with AAA (70±8 years, 84% men) and 2686 controls (68±10 years, 61% men) recruited from noninvasive vascular and stress electrocardiogram (ECG) laboratories at Mayo Clinic. AAA was defined as a transverse diameter of abdominal aorta ⩾ 3 cm or history of AAA repair. Controls were not known to have AAA. FHx was defined as having at least one first-degree relative with aortic aneurysm or with onset of ASCVD (coronary, cerebral or peripheral artery disease) before age 65 years. FHx of aortic aneurysm or ASCVD were each associated with presence of AAA after adjustment for age, sex, conventional risk factors and ASCVD: adjusted odds ratios (OR; 95% confidence interval): 2.17 (1.66–2.83, p < 0.01) and 1.31 (1.08–1.59, p < 0.01), respectively. FHx of ASCVD remained associated with AAA after additional adjustment for FHx of aortic aneurysm: adjusted OR: 1.27 (1.05–1.55, p = 0.01). FHx of ASCVD in multiple arterial locations was associated with higher odds of having AAA: the adjusted odds were 1.23 times higher for each additionally affected arterial location reported in the FHx (1.08–1.40, p = 0.01). Our results suggest both unique and shared environmental and genetic factors mediating susceptibility to AAA and ASCVD.

The burden and predictors of hospitalization over time in community-based patients with peripheral artery disease (PAD) have not been established. This study evaluates the frequency, reasons and predictors of hospitalization over time in community-based patients with PAD. We assembled an inception cohort of 1798 PAD cases from Olmsted County, MN, USA (mean age 71.2 years, 44% female) from 1 January 1998 through 31 December 2011 who were followed until 2014. Two age- and sex-matched controls ( n = 3596) were identified for each case. ICD-9 codes were used to ascertain the primary reasons for hospitalization. Patients were censored at death or last follow-up. The most frequent reasons for hospitalization were non-cardiovascular: 68% of 8706 hospitalizations in cases and 78% of 8005 hospitalizations in controls. A total of 1533 (85%) cases and 2286 (64%) controls ( p < 0.001) were hospitalized at least once; 1262 (70%) cases and 1588 (44%) controls ( p < 0.001) ≥ two times. In adjusted models, age, prior hospitalization and comorbid conditions were independently associated with increased risk of recurrent hospitalizations in both groups. In cases, severe PAD (ankle–brachial index < 0.5) (HR: 1.25; 95% CI: 1.15, 1.36) and poorly compressible arteries (HR: 1.26; 95% CI: 1.16, 1.38) were each associated with increased risk for recurrent hospitalization. We demonstrate an increased rate of hospitalization in community-based patients with PAD and identify predictors of recurrent hospitalizations. These observations may inform strategies to reduce the burden of hospitalization of PAD patients.

Most familial hypercholesterolemia (FH) patients remain undertreated, and it is unclear what role health disparities may play for FH patients in the US. We sought to describe sex and racial/ethnic disparities in a national registry of US FH patients.We analyzed data from 3167 adults enrolled in the CAscade SCreening for Awareness and DEtection of Familial Hypercholesterolemia (CASCADE-FH) registry. Logistic regression was used to evaluate for disparities in LDL-C goals and statin use, with adjustments for covariates including age, cardiovascular risk factors, and statin intolerance.In adjusted analyses, women were less likely than men to achieve treated LDL-C of100 mg/dL (OR 0.68, 95% CI, 0.57-0.82) or ≥50% reduction from pretreatment LDL-C (OR 0.79, 95% CI, 0.65-0.96). Women were less likely than men to receive statin therapy (OR, 0.60, 95% CI, 0.50-0.73) and less likely to receive a high-intensity statin (OR, 0.60, 95% CI, 0.49-0.72). LDL-C goal achievement also varied by race/ethnicity: compared with whites, Asians and blacks were less likely to achieve LDL-C levels100 mg/dL (Asians, OR, 0.47, 95% CI, 0.24-0.94; blacks, OR, 0.49, 95% CI, 0.32-0.74) or ≥50% reduction from pretreatment LDL-C (Asians, OR 0.56, 95% CI, 0.32-0.98; blacks, OR 0.62, 95% CI, 0.43-0.90).In a contemporary US population of FH patients, we identified differences in LDL-C goal attainment and statin usage after stratifying the population by either sex or race/ethnicity. Our findings suggest that health disparities contribute to the undertreatment of US FH patients. Increased efforts are warranted to raise awareness of these disparities.

Background— One potential use for the PR interval is as a biomarker of disease risk. We hypothesized that quantifying the shared genetic architectures of the PR interval and a set of clinical phenotypes would identify genetic mechanisms contributing to PR variability and identify diseases associated with a genetic predictor of PR variability. Methods and Results— We used ECG measurements from the ARIC study (Atherosclerosis Risk in Communities; n=6731 subjects) and 63 genetically modulated diseases from the eMERGE network (Electronic Medical Records and Genomics; n=12 978). We measured pairwise genetic correlations (rG) between PR phenotypes (PR interval, PR segment, P-wave duration) and each of the 63 phenotypes. The PR segment was genetically correlated with atrial fibrillation (rG=−0.88; P =0.0009). An analysis of metabolic phenotypes in ARIC also showed that the P wave was genetically correlated with waist circumference (rG=0.47; P =0.02). A genetically predicted PR interval phenotype based on 645 714 single-nucleotide polymorphisms was associated with atrial fibrillation (odds ratio=0.89 per SD change; 95% confidence interval, 0.83–0.95; P =0.0006). The differing pattern of associations among the PR phenotypes is consistent with analyses that show that the genetic correlation between the P wave and PR segment was not significantly different from 0 (rG=−0.03 [0.16]). Conclusions— The genetic architecture of the PR interval comprises modulators of atrial fibrillation risk and obesity.

Exercise testing provides valuable information but is rarely integrated to derive a risk prediction model in a referral population. In this study, we assessed the predictive value of conventional cardiovascular risk factors and exercise test parameters in 6,546 consecutive adults referred for exercise testing, who were followed for a period of 8.1 ± 3.7 years for incident myocardial infarction, coronary revascularization, and cardiovascular death. A risk prediction model was developed, and cross-validation of model was performed by splitting the data set into 10 equal random subsets, with model fitting based on 9 of the 10 subsets and testing in of the remaining subset, repeated in all 10 possible ways. The best performing model was chosen based on measurements of model discrimination and stability. A risk score was constructed from the final model, with points assigned for the presence of each predictor based on the regression coefficients. Using both conventional risk factors and exercise test parameters, a total of 9 variables were identified as independent and robust predictors and were included in a risk score. The prognostic ability of this model was compared with that of the Adult Treatment Panel III model using the net reclassification and integrated discrimination index. From the cross-validation results, the c statistic of 0.77 for the final model indicated strong predictive power. In conclusion, we developed, tested, and internally validated a novel risk prediction model using exercise treadmill testing parameters.

The association of a family history of peripheral arterial disease (PAD) with the presence of PAD is largely unknown. We conducted a case-control study of 2,296 patients with PAD (69 ± 10 years, 64% men) and 4,390 controls (66 ± 11 years, 62% men) identified from noninvasive vascular and stress testing laboratories at Mayo Clinic, Rochester, Minnesota, from October 2006 through June 2012. PAD was defined as an ankle brachial index of ≤ 0.9 at rest and/or after exercise, a history of lower extremity revascularization, or having poorly compressible leg arteries. Controls were patients with normal ankle brachial index or without a history of PAD. Family history of PAD was defined as having at least 1 first-degree relative who had undergone revascularization or stent placement for PAD before the age of 65 years. Logistic regression analyses were used to evaluate whether a family history of PAD was associated with the presence of PAD, independent of conventional risk factors. A family history of PAD was present more often in patients with PAD than in controls, with a resulting odds ratio (OR) of 2.20 (95% confidence interval [CI] 1.82 to 2.67). The association remained significant after adjustment for conventional risk factors (OR 1.97, 95% CI 1.60 to 2.42). The association was stronger in younger subjects (age68 years; adjusted OR 2.46, 95% CI 1.79 to 3.38) than in older subjects (adjusted OR 1.61, 95% CI 1.22 to 2.12). A greater number of affected relatives with PAD was also associated with greater odds of presence of PAD (adjusted OR 1.86, 95% CI 1.48 to 2.33 and adjusted OR 2.56, 95% CI 1.60 to 4.11 for patients with 1 and ≥ 2 affected relatives with PAD, respectively). In conclusion, individuals with a family history of PAD have nearly double the odds of having PAD relative to those without such a history.

Objective Increased aortic stiffness may be one of the mechanisms by which obesity increases cardiovascular risk independently of traditional risk factors. While body mass index (BMI) is generally used to define excess adiposity, several studies have suggested that measures of central obesity may be better predictors of cardiovascular risk. However, data comparing the association between several measures of central and general obesity with aortic stiffness in the general population are inconclusive. Methods In 1031 individuals (age 53 ± 13 years, 45% men) without manifest cardiovascular disease randomly selected from population, we tested the association between parameters of central obesity (waist circumference – WC, waist-to-hip-ratio – WHR, waist-to-height ratio – WHtR) and general obesity (BMI) with carotid-femoral pulse wave velocity (cfPWV). Results In univariate analysis, WC and WHtR were more strongly associated with cfPWV than BMI in both genders, while WHR showed a stronger association with cfPWV only in women. WHtR was more closely associated with cfPVW than WHR. This difference between obesity measures remained after multivariate adjustment. When the fully adjusted hierarchical regression was used, among central obesity measures, WHtR had the largest additive value on top of BMI, while there was no additive value of BMI on top of WHtR. Conclusion Central obesity parameters are more closely associated with aortic stiffness than BMI. Of central adiposity measures, WHtR has the strongest association with aortic stiffness beyond body mass index and cardiovascular risk factors. Our results suggest that WHtR may be the best anthropometric measure of excess adiposity in the general population.

Arterial stiffness is associated with incident hypertension. We hypothesized that measures of arterial stiffness would predict increases in systolic (SBP), mean (MAP), and pulse pressure (PP) over time in treated hypertensives. Blood pressure (BP) was measured a mean of 8.5 ± 0.9 years apart in 414 non-Hispanic white hypertensives (mean age, 60 ± 8 years; 55% women). The average of three supine right brachial BPs was recorded. Measures of arterial stiffness, including carotid-femoral pulse wave velocity (cfPWV), aortic augmentation index (AIx), and central pulse pressure (CPP), were obtained at baseline by applanation tonometry. We performed stepwise multivariable linear regression analyses adjusting for potential confounders to assess the associations of arterial stiffness parameters with BP changes over time. SBP, MAP, and PP increased in 80% of participants. After adjustment for covariates listed, cfPWV (m/s) was associated with increases in SBP (β ± standard error [SE], 0.71 ± 0.31) and PP (β ± SE, 1.09 ± 0.27); AIx (%) was associated with increases in SBP (β ± SE, 0.23 ± 0.10) and MAP (β ± SE, 0.27 ± 0.07); and CPP (mmHg) was associated with increases in SBP (β ± SE, 0.44 ± 0.07), MAP (β ± SE, 0.24 ± 0.05), and PP (β ± SE, 0.42 ± 0.06) over time (P ≤ .02 for each). In conclusion, arterial stiffness measures were associated with longitudinal increases in SBP, MAP, and PP in treated hypertensives.

Despite advances in our understanding of heritable lipid disorders and the availability of highly effective lipid-lowering drugs, the awareness, detection, and control of familial hypercholesterolemia (FH) remain suboptimal. 1 A major reason for the low detection rate in the United States is the lack of a widely accepted screening strategy, despite the recommendations for universal or targeted lipid screening by several expert panels. Although the use of universal lipid screening remains a matter of debate, cascade screening (a form of targeted screening of family members of affected individuals) is acknowledged as the most cost-effective screening strategy for FH. In the Netherlands >26 000 new cases were identified over 2 decades by genotyping family members of FH probands, and it is estimated that genetic cascade screening, coupled with statin therapy for diagnosed patients, could save $92 million per year in the European Union. 1 Several factors lead to the low rates of cascade screening for FH in the United States. First, no nationwide strategy for the early detection of FH exists. Second, the low acceptance of genetic testing for FH in the United States is an impediment to unambiguous diagnosis and cascade screening. Third, patients and family members are often concerned about the stigma associated with genetic diagnoses. Fourth, because of the Health Insurance Portability and Accountability Act, disclosing the risk of genetic disease to family members can incur liability, even if this knowledge leads to early detection and treatment. Fifth, …

Premature coronary heart disease (pCHD), defined as onset before age 55 in males and age 65 in females, often occurs in the absence/paucity of conventional risk factors. We compared the strength of association of polygenic risk scores (PRS) with pCHD. We evaluated PRSs in 915 (60±8 y, 42% male)