scholarly journals Outcomes and phenotypic expression of rare variants in hypertrophic cardiomyopathy genes amongst UK Biobank participants

Author(s):  
Antonio de Marvao ◽  
Kathryn A McGurk ◽  
Sean L Zheng ◽  
Marjola Thanaj ◽  
Wenjia Bai ◽  
...  

AbstractBackgroundHypertrophic cardiomyopathy (HCM) is caused by rare variants in sarcomere-encoding genes, but little is known about the clinical significance of these variants in the general population.MethodsWe compared outcomes and cardiovascular phenotypes in UK Biobank participants with whole exome sequencing stratified by sarcomere-encoding variant status.ResultsThe prevalence of rare variants (allele frequency <0.00004) in HCM-associated sarcomere-encoding genes in 200,584 participants was 2.9% (n=5,727; 1 in 35), of which 0.24% (n=474, 1 in 423) were pathogenic or likely pathogenic variants (SARC-P/LP). SARC-P/LP variants were associated with increased risk of death or major adverse cardiac events compared to controls (HR 1.68, 95% CI 1.37-2.06, p<0.001), mainly due to heart failure (HR 4.40, 95% CI 3.22-6.02, p<0.001) and arrhythmia (HR 1.55, 95% CI 1.18-2.03, p=0.002). In 21,322 participants with cardiac magnetic resonance imaging, SARC-P/LP were associated with increased left ventricular maximum wall thickness (10.9±2.7 vs 9.4±1.6 mm, p<0.001) and concentric remodelling (mass/volume ratio: 0.63±0.12 vs 0.58±0.09 g/mL, p<0.001), but hypertrophy (≥13mm) was only present in 16% (n=7/43, 95% CI 7-31%). Other rare sarcomere-encoding variants had a weak effect on wall thickness (9.5±1.7 vs 9.4±1.6 mm, p=0.002) with no combined excess cardiovascular risk (HR 1.00 95% CI 0.92-1.08, p=0.9).ConclusionsIn the general population, SARC-P/LP variants have low aggregate penetrance for overt HCM but are associated with an increased risk of adverse cardiovascular outcomes and a sub-clinical cardiomyopathic phenotype. In contrast, rare sarcomeric variants that do not meet criteria to be classified as P/LP appear to have minimal clinical impact.

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
A De Marvao ◽  
K McGurk ◽  
S Zheng ◽  
M Thanaj ◽  
W Bai ◽  
...  

Abstract Background Hypertrophic cardiomyopathy (HCM) is caused by rare variants in sarcomere-encoding genes, but little is known about the clinical significance of these variants in the general population. Purpose To determine the population prevalence of HCM-associated sarcomeric variants, characterise their phenotypic manifestations, estimate penetrance, and identify associations between sarcomeric variants and clinical outcomes, we performed an observational study of 218,813 adults in the UK Biobank (UKBB), of whom 200,584 have whole exome sequencing (WES). Methods We carried out an integrated analysis of WES and cardiac magnetic resonance (CMR) imaging in UK Biobank participants stratified by sarcomere-encoding variant status. Computer vision techniques were used to automatically segment the four chambers of the heart (Figure 1). Cardiac motion analysis was used to derive strain and strain rates. Regional analysis of left ventricular wall thickness was performed using three-dimensional modelling of these segmentations. Results Median age at recruitment was 58 (IQR 50–63 years), and participants were followed up for a median of 10.8 years (IQR 9.9–11.6 years) with a total of 19,507 primary clinical events reported. The prevalence of rare variants (allele frequency &lt;0.ehab724.17314) in HCM-associated sarcomere-encoding genes in 200,584 participants was 2.9% (n=5,727; 1 in 35), and the prevalence of pathogenic or likely pathogenic variants (SARC-P/LP) was 0.24% (n=474, 1 in 423). SARC-P/LP variants were associated with increased risk of death or major adverse cardiac events (MACE) compared to controls (HR 1.68, 95% CI 1.37–2.06, p&lt;0.001), mainly due to heart failure endpoints (Figure 2: cumulative hazard curves with zoomed plots for lifetime risk of A) death and MACE or B) heart failure, stratified by genotype; genotype negative (SARC-NEG), carriers of indeterminate sarcomeric variants (SARC-IND) or SARC-P/LP; C) Forest plot of comparative lifetime risk of clinical endpoints by genotype). While males had a higher overall risk of adverse outcomes, the incremental genetic risk from SARC-P/LP mutations was greater in females (HR for females: 2.18 CI 1.65–2.89, p&lt;0.001; HR for males: 1.42 CI 1.05–1.9, p=0.02). In 21,322 participants with CMR, SARC-P/LP were associated with asymmetric increase in left ventricular maximum wall thickness (10.9±2.7 vs 9.4±1.6 mm, p&lt;0.001) but hypertrophy (≥13mm) was only present in 16% (n=7/43, 95% CI 7–31%). Other rare sarcomere-encoding variants had a weak effect on wall thickness (9.5±1.7 vs 9.4±1.6 mm, p=0.002) with no combined excess cardiovascular risk. Conclusions In the general population, SARC-P/LP variants have low aggregate penetrance for overt HCM but are associated with increased risk of adverse cardiovascular outcomes and a sub-clinical cardiomyopathic phenotype. Although absolute event rates are low, identification of these variants may enhance risk stratification beyond familial disease. FUNDunding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The study was supported by the Medical Research Council, UK (MC-A651-53301); National Institute for Health Research (NIHR) Imperial College Biomedical Research Centre; NIHR Royal Brompton Cardiovascular Biomedical Research Unit; British Heart Foundation (NH/17/1/32725, RG/19/6/34387, RE/18/4/34215).


Author(s):  
Carmen Chan ◽  
Martin S Maron

Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy and the most common cause of sudden death in young people, as well as a cause of limiting heart failure symptoms at any age. Mutations in the cardiac sarcomere, the structural apparatus of the heart muscle, cause HCM and a diagnosis is made when maximal left ventricular (LV) wall thickness is ≥15 mm in the absence of another cause. Cardiovascular magnetic resonance (CMR) can reliably identify areas of increased LV wall thickness, as well as detailed characterization of myocardial structures such as the papillary muscles and mitral valve, with implications on management strategies. In addition, contrast-enhanced CMR with late gadolinium enhancement sequences (LGE) can identify areas of myocardial fibrosis/scarring in patients with HCM. Extensive LGE is an important marker for development of future systolic dysfunction and may identify patients at increased risk for ventricular tachyarrhythmias and cardiac mortality. As a result, CMR currently serves an important and evolving role in the evaluation of HCM patients by providing information with regard to diagnosis, morphology, and clinical course in HCM patients.


2021 ◽  
Vol 14 (1) ◽  
pp. 5-11
Author(s):  
AKM Monwarul Islam ◽  
Dipal K Adhikary ◽  
Shovan Rahman ◽  
Mohsin Ahmed ◽  
Md Toufiqur Rahman ◽  
...  

Background: Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disease of left ventricular hypertrophy (LVH). Phenotypic expression varies widely from subclinical hypertrophy to gross asymmetric septal hypertrophy causing left ventricular outflow tract (LVOT) obstruction. On top of genetic and phenotypic heterogeneity, the prevalence of different types of HCM may have geographical, as well as, ethnic variation. Methods: This observational study was carried out during 2010 to 2020 to determine the echocardiographic profile of HCM in Bangladeshi population. All patients undergoing transthoracic echocardiography (TTE) in a private consultation centre of Dhaka, Bangladesh were included. HCM was defined as the presence of a maximal end-diastolic wall thickness of e”15 mm anywhere in the left ventricle (LV), in the absence of another cause of hypertrophy in adults. HCM was further classified according to the pattern of myocardial hypertrophy and presence or absence of LVOT, or mid-left ventricular cavity obstruction. Results: Out of 76 cases, non-obstructive HCM was the commonest type (65.8%), followed by HCM causing LVOT obstruction (13.2%), HCM causing mid-LV cavity obstruction (10.5%), and the apical variety ( 10.5%). Asymmetric septal hypertrophy (ASH) was found in 42.1%, systolic anterior motion (SAM) of anterior mitral leaflet (AML) in 14.5%, mitral regurgitation (MR) in 50%, left ventricular systolic dysfunction in 5.3%, and raised pulmonary artery systolic pressure (PASP) in 15.8% of cases. Maximum LV wall thickness ≥30 mm was found in 66 out of 76 cases. Conclusion: The study highlights the clinically useful profile of HCM in Bangladeshi population based on conventional echocardiography. Further studies involving clinical, newer echocardiographic modalities and genetic analyses are warranted to discover the additional information in this ethnicity. Cardiovasc j 2021; 14(1): 5-11


Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Maria DeFonte ◽  
Jonathan Goldstein ◽  
Daniele Massera ◽  
Alexandra Stepanovic ◽  
Alexander Gee ◽  
...  

Introduction: Hypertrophic Cardiomyopathy (HCM) is a relatively common inherited heart disease with variable phenotypic expression. While pathogenic variants in sarcomeric genes are considered responsible for the development of left ventricular (LV) hypertrophy, environmental modulation of phenotype may explain the known heterogeneity. Obesity is common in HCM patients and is associated with increased LV mass in the general population. Hypothesis: We hypothesized that weight loss in obese patients with HCM would be associated with a decrease in LV mass and maximal wall thickness. Methods: Patients with HCM who achieved therapeutic weight loss and underwent cardiac MRI (CMR) or computed tomography (CT) before and afterwards were included. Standard LV measurements including wall thickness in an 18-segment model were performed blindly with respect to name, time and BMI for un-biased comparison. Results: We included 6 patients (2 female, age 55 ± 6.5 years, baseline BMI = 36.7 ± 5.2 kg/m 2 ) who achieved 16.3 ± 10.8 kg weight loss after 35 ± 12 months with diet and exercise (n=4) or bariatric surgery (n=2). After weight loss, we observed a mean proportional decrease in total LV mass of 25 ± 16% (p=0.004), and a 19 ± 7% decrease in indexed LV mass (p=0.007). Furthermore, there was a numerical decrease in mean wall thickness in 14 out of 18 LV segments measured; 9 segments had more than a 10% decrease. The most noticeable changes were at the basal inferolateral wall (25 ± 13% decrease) and basal inferoseptum (19 ± 18%) decrease (Table). Conclusions: In this series of patients with HCM, weight loss favorably affected LV mass and wall thickness. Further research is needed to explore the impact of weight loss on HCM phenotypic expression and symptoms.


2016 ◽  
Vol 5 (3) ◽  
pp. 197 ◽  
Author(s):  
Ethan J Rowin ◽  
Martin S Maron ◽  
◽  

Hypertrophic cardiomyopathy (HCM), the most common genetic cardiomyopathy, is a disease characterised by substantial heterogeneity. Although the majority of patients with HCM remain asymptomatic with near-normal longevity, a small, but important, subset remain at risk for a wide range of clinical outcomes including sudden death. Cardiovascular magnetic resonance (CMR), with its high spatial resolution and tomographic imaging capability, has emerged as an imaging modality particularly well suited to characterise the phenotypic expression of HCM. CMR helps in the diagnosis of HCM by identifying areas of hypertrophy not well visualised by echocardiography, providing more accurate wall thickness measurements and differentiating HCM from other causes of left ventricular (LV) hypertrophy. CMR has led to the identification of novel subgroups of patients with HCM, including those with LV apical aneurysms (a subgroup at increased risk for ventricular arrhythmias and thromboembolic stroke), as well as abnormalities that contribute to LV outflow obstruction. Additionally, contrast-enhanced CMR with late-gadolinium enhancement (LGE) has recognised patients with extensive LGE (≥15 % LV myocardium) as individuals who may be at increased risk of sudden death, independent of other high-risk features, with implications on management strategies including consideration for primary prevention implantable cardioverter defibrillator therapy. These observations justify an expanded role of CMR in the routine clinical assessment of patients with HCM.


Author(s):  
Erika N Aagaard ◽  
Brede Kvisvik ◽  
Mohammad O Pervez ◽  
Magnus N Lyngbakken ◽  
Trygve Berge ◽  
...  

Abstract Aims Increased left ventricular mechanical dispersion by 2D speckle tracking echocardiography predicts ventricular arrhythmias in ischaemic heart disease and heart failure. However, little is known about mechanical dispersion in the general population. We aimed to study mechanical dispersion in the general population and in diseases associated with increased risk of cardiovascular disease. Methods and results The present cross-sectional study consists of 2529 subjects born in 1950 included in the Akershus Cardiac Examination (ACE) 1950 study. Global longitudinal strain (GLS) was assessed from 17 strain segments, and mechanical dispersion calculated as the standard deviation of contraction duration of all segments. The cohort was divided according to the median value of mechanical dispersion, and multivariable linear regression models were performed with mechanical dispersion as the dependent variable. The prevalence of coronary artery disease (CAD), hypertension, obesity, and diabetes (P < 0.01 for all) was significantly higher in subjects with supra-median mechanical dispersion. In a multivariable clinical model, CAD (B = 7.05), hypertension (B = 4.15; both P < 0.001), diabetes (B = 3.39), and obesity (B = 1.89; both P < 0.05) were independently associated with increasing mechanical dispersion. When echocardiographic indices were added to the multivariable model, CAD (B = 4.38; P < 0.01) and hypertension (B = 2.86; P < 0.001) remained significant in addition to peak early diastolic tissue velocity e’ (B = −2.00), GLS (B = 1.68), and ejection fraction (B = 0.22; P < 0.001 for all). Conclusion In a general middle-aged population, prevalent CAD and hypertension were associated with increasing mechanical dispersion, possibly indicating elevated risk of fatal arrhythmias and sudden cardiac death. Albeit weaker, systolic and diastolic dysfunction, were also associated with increasing mechanical dispersion.


2017 ◽  
Vol 77 (1) ◽  
pp. 85-91 ◽  
Author(s):  
Marie Holmqvist ◽  
Lotta Ljung ◽  
Johan Askling

ObjectiveTo investigate if, and when, patients diagnosed with rheumatoid arthritis (RA) in recent years are at increased risk of death.MethodsUsing an extensive register linkage, we designed a population-based nationwide cohort study in Sweden. Patients with new-onset RA from the Swedish Rheumatology Quality Register, and individually matched comparators from the general population were followed with respect to death, as captured by the total population register.Results17 512 patients with new-onset RA between 1 January 1997 and 31 December 2014, and 78 847 matched general population comparator subjects were followed from RA diagnosis until death, emigration or 31 December 2015. There was a steady decrease in absolute mortality rates over calendar time, both in the RA cohort and in the general population. Although the relative risk of death in the RA cohort was not increased (HR=1.01, 95% CI 0.96 to 1.06), an excess mortality in the RA cohort was present 5 years after RA diagnosis (HR after 10 years since RA diagnosis=1.43 (95% CI 1.28 to 1.59)), across all calendar periods of RA diagnosis. Taking RA disease duration into account, there was no clear trend towards lower excess mortality for patients diagnosed more recently.ConclusionsDespite decreasing mortality rates, RA continues to be linked to an increased risk of death. Thus, despite advancements in RA management during recent years, increased efforts to prevent disease progression and comorbidity, from disease onset, are needed.


2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
F Loncaric ◽  
A Garcia-Alvarez ◽  
P Garcia-Canadilla ◽  
L Sanchiz ◽  
H Dejea ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Horizon 2020 European Commission Project H2020-MSCA-ITN-2016 (764738) and the Clinical Research in Cardiology grant from the Spanish Cardiac Society. Background The aetiology of left ventricular hypertrophy (LVH) is a relevant clinical challenge with consequences for patient management. Phenotypes resulting from hypertensive remodelling and sarcomere mutation often overlap. Synchrotron X-ray phase-contrast imaging (X-PCI) is a technique that can provide 3-dimensional detailed information on myocardial micro-structure non-destructively. The aim is to relate macrostructural/functional, non-invasive, imaging phenotypes of hypertrophic cardiomyopathy (HCM) to the underlying myocardial microstructure assessed with X-PCI. Methods Myocardial tissue samples were obtained from three patients (P1-3) with obstructive myocardial hypertrophy undergoing septal myectomy. Medical history and the 5-year HCM risk scores were evaluated. The patients were imaged with magnetic resonance imaging and echocardiography prior to procedure. Myocardial structure was assessed with wall thickness, late gadolinium enhancement (LGE), whereas function with speckle-tracking deformation (STE) and tissue Doppler imaging (TDI). Myectomy tissue was imaged with X-PCI in the TOMCAT beamline, using a multiscale propagation-based protocol combining a low-resolution (LR) and a high-resolution (HR) setup (5.8 and 0.7 um pixel size, respectively). Results The clinical and imaging data are shown in Fig 1. On initial assessment, wall thickness, LGE distribution, global longitudinal strain and septal TDI demonstrated a similar macrostructural and functional phenotype of P1 and P2, whereas P3 stood out with more severe hypertrophy, scarring and dysfunction. Additional regional deformation analysis with STE revealed reduced deformation in the basal and mid septum in P1, paired with a hypertensive pattern of post-systolic shortening (PSS) (yellow arrows). In comparison, in P2 and P3, deformation was more heterogeneous regionally, with regions of almost complete absence of deformation (orange arrows). Upon further exploration with TDI, areas with abnormal deformation were identified on the transition from basal to mid septum in both P2 and P3, whereas deformation was normal, but reduced in P1, and paired with PSS. LR X-PCI defined regions of interest to scan with HR (yellow frame), where HR revealed extensive interstitial fibrosis (orange arrow) with normal myocyte size and organisation in P1, compatible with severe hypertensive remodelling. However, in P2 and P3, patches of fibrosis (yellow arrow) paired with enlarged myocytes organized in visible disarray, considerably more prominent in P3, were both compatible with sarcomere-mutation HCM. Conclusion The results demonstrate multiscale phenotyping of HCM - relating micro- and macrostructural findings to function, and integrating multimodality data. In-depth regional deformation analysis, validated by synchrotron-based microstructural analysis, showed potential to identify distinct imaging phenotypes in HCM, distinguishing between overlapping presentations in different aetiologies. Abstract Figure 1


2017 ◽  
Vol 46 (4) ◽  
pp. 343-354 ◽  
Author(s):  
Ngan N. Lam ◽  
Amit X. Garg ◽  
Greg A. Knoll ◽  
S. Joseph Kim ◽  
Krista L. Lentine ◽  
...  

Background: The implications of venous thromboembolism (VTE) for morbidity and mortality in kidney transplant recipients are not well described. Methods: We conducted a retrospective study using linked healthcare databases in Ontario, Canada to determine the risk and complications of VTE in kidney transplant recipients from 2003 to 2013. We compared the incidence rate of VTE in recipients (n = 4,343) and a matched (1:4) sample of the general population (n = 17,372). For recipients with evidence of a VTE posttransplant, we compared adverse clinical outcomes (death, graft loss) to matched (1:2) recipients without evidence of a VTE posttransplant. Results: During a median follow-up of 5.2 years, 388 (8.9%) recipients developed a VTE compared to 254 (1.5%) in the matched general population (16.3 vs. 2.4 events per 1,000 person-years; hazard ratio [HR] 7.1, 95% CI 6.0-8.4; p < 0.0001). Recipients who experienced a posttransplant VTE had a higher risk of death (28.5 vs. 11.2%; HR 4.1, 95% CI 2.9-5.8; p < 0.0001) and death-censored graft loss (13.1 vs. 7.5%; HR 2.3, 95% CI 1.4-3.6; p = 0.0006) compared to matched recipients who did not experience a posttransplant VTE. Conclusions: Kidney transplant recipients have a sevenfold higher risk of VTE compared to the general population with VTE conferring an increased risk of death and graft loss.


Sign in / Sign up

Export Citation Format

Share Document