82 hot topic(s) found with the query "Atrial fibrillation"
Prediction of atrial fibrillation from at-home single-lead ECG signals without arrhythmias
M Gadaleta et al, NPJ Digital Medicine, December 12, 2023
(Posted: Dec 12, 2023 9AM)
From the abstract: "Early identification of atrial fibrillation (AF) can reduce the risk of stroke, heart failure, and other serious cardiovascular outcomes. However, paroxysmal AF may not be detected even after a two-week continuous monitoring period. We developed a model to quantify the risk of near-term AF in a two-week period, based on AF-free ECG intervals of up to 24?h from 459,889 patch-based ambulatory single-lead ECG (modified lead II) recordings of up to 14 days "
Genetic Susceptibility to Atrial Fibrillation Identified via Deep Learning of 12-Lead Electrocardiograms.
Xin Wang et al. Circ Genom Precis Med 2023 6 e003808
(Posted: Jun 09, 2023 7AM)
We applied a validated ECG-AI model for predicting incident AF to ECGs from 39 986 UK Biobank participants without AF. We then performed a genome-wide association study (GWAS) of the predicted AF risk and compared it with an AF GWAS and a GWAS of risk estimates from a clinical variable model.
In the ECG-AI GWAS, we identified 3 signals (P<5×10-8) at established AF susceptibility loci marked by the sarcomeric gene TTN and sodium channel genes SCN5A and SCN10A. Predicted AF risk from an ECG-AI model is influenced by genetic variation implicating sarcomeric, ion channel and body height pathways. ECG-AI models may identify individuals at risk for disease via specific biological pathways.
Genetic testing in monogenic early-onset atrial fibrillation.
Brandon Chalazan et al. Eur J Hum Genet 2023 5
(Posted: May 23, 2023 11AM)
We aim to determine the prevalence of likely pathogenic and pathogenic variants from AF genes with robust evidence in a well phenotyped early-onset AF population. We performed whole exome sequencing on 200 early-onset AF patients. Variants from exome sequencing in affected individuals were filtered in a multi-step process, prior to undergoing clinical classification using current ACMG/AMP guidelines. There was a 3.0% diagnostic yield for identifying a likely pathogenic or pathogenic variant across AF genes with robust gene-to-disease association evidence.
Generalizable and robust deep learning algorithm for atrial fibrillation diagnosis across geography, ages and sexes.
Shany Biton et al. NPJ digital medicine 2023 3 (1) 44
(Posted: Mar 18, 2023 3PM)
This retrospective study attempts to develop and assess the generalization performance of a DL model for AF events detection from long term beat-to-beat intervals across geography, ages and sexes. The new recurrent DL model, denoted ArNet2, is developed on a large retrospective dataset of 2,147 patients totaling 51,386?h obtained from continuous electrocardiogram (ECG). The model’s generalization is evaluated on manually annotated test sets from four centers (USA, Israel, Japan and China) totaling 402 patients. The model is further validated on a retrospective dataset of 1,825 consecutives Holter recordings.
Association of accelerometer-derived circadian abnormalities and genetic risk with incidence of atrial fibrillation
L Yang et al, NPJ Digital Medicine, March 4, 2023
(Posted: Mar 04, 2023 9AM)
In this large population-based cohort, we found that circadian rest-activity rhythm (CRAR) abnormalities, hallmarked by low amplitude, delayed acrophase, and low mesor (but not pseudo-F), were strongly associated with AF risk. When examining the joint associations of CRAR and genetic risk with AF incidence, high genetic risk in combination with CRAR abnormalities was associated with a more than 2.5-fold greater risk of AF compared with low genetic risk and normal CRAR.
Association of Hypertensive Disorders of Pregnancy With Future Cardiovascular Disease.
Bilal Rayes et al. JAMA network open 2023 2 (2) e230034
(Posted: Feb 18, 2023 8AM)
Is there evidence for an association between hypertensive disorders of pregnancy (HDPs) and long-term risk of cardiovascular disease? In this large genome-wide genetic association study using mendelian randomization, HDPs were associated with higher risk of coronary artery disease and ischemic stroke but not heart failure or atrial fibrillation. Mediation analysis revealed a partial attenuation of the association between HDPs and coronary artery disease after adjustment for systolic blood pressure and type 2 diabetes. These results support the consideration of HDPs as potential risk factors for cardiovascular disease.
Cross-ancestry genome-wide analysis of atrial fibrillation unveils disease biology and enables cardioembolic risk prediction
K Miyazawa et al, Nature Genetics, January 19, 2023
(Posted: Jan 19, 2023 7AM)
Here we performed a genome-wide association study in the Japanese population comprising 9,826 cases among 150,272 individuals and identified East Asian-specific rare variants associated with AF. A cross-ancestry meta-analysis of >1 million individuals, including 77,690 cases, identified 35 new susceptibility loci. Transcriptome-wide association analysis identified IL6R as a putative causal gene, suggesting the involvement of immune responses.
Cardiomyopathy prevalence exceeds 30% in individuals with TTN variants and early atrial fibrillation.
Schiabor Barrett Kelly M et al. Genetics in medicine : official journal of the American College of Medical Genetics 2023 1 100012
(Posted: Jan 16, 2023 6AM)
Truncating variants in TTN (TTNtvs) represent the largest known genetic cause of dilated cardiomyopathies (DCM), but their penetrance for DCM in general populations is low. More broadly, patients with cardiomyopathies (CM) often exhibit other cardiac conditions, such as atrial fibrillation (Afib), which has also been linked to TTNtvs. This retrospective analysis aims to characterize the relationship between different cardiac conditions in those with TTNtvs and identify individuals with the highest risk of DCM.
Genomics and phenomics of body mass index reveals a complex disease network.
Huang Jie et al. Nature communications 2022 12 (1) 7973
(Posted: Jan 02, 2023 0PM)
Using a BMI genetic risk score including 2446 variants, 316 diagnoses are associated in the Million Veteran Program, with 96.5% showing increased risk. A co-morbidity network analysis reveals seven disease communities containing multiple interconnected diseases associated with BMI as well as extensive connections across communities. Mendelian randomization analysis confirms phenotypes across many organ systems, including conditions of the circulatory (heart failure, ischemic heart disease, atrial fibrillation), genitourinary (chronic renal failure), respiratory (respiratory failure, asthma), musculoskeletal and dermatologic systems.
Prediction of atrial fibrillation and stroke using machine learning models in UK Biobank.
A Papadopolou et al, MEDRXIV, October 30, 2022
(Posted: Oct 31, 2022 9AM)
Transcriptomics-based network medicine approach identifies metformin as a repurposable drug for atrial fibrillation
JC Lal et al, Cell Reports Med, October 11, 2022
(Posted: Oct 12, 2022 8AM)
Using the active compactor, a new design analysis of large-scale longitudinal electronic health record (EHR) data, we determine that metformin use is significantly associated with a reduced risk of AF (odds ratio = 0.48, 95%, confidence interval [CI] 0.36–0.64, p < 0.001) compared with standard treatments for diabetes.
Smartphone-based screening for atrial fibrillation: a pragmatic randomized clinical trial
KD Rizas et al, Nature Medicine, August 28, 2022
(Posted: Aug 29, 2022 1PM)
Digital smart devices have the capability of detecting atrial fibrillation (AF), but the efficacy of this type of digital screening has not been directly compared to usual care for detection of treatment-relevant AF. In the eBRAVE-AF trial (NCT04250220), we randomly assigned 5,551 policyholders of a German health insurance company who were free of AF at baseline (age 65?years (median; interquartile range (11) years, 31% females)) to digital screening (n?=?2,860) or usual care (n?=?2,691). We found that this digital screening technology provides substantial benefits in detecting AF compared to usual care and has the potential for broad applicability due to its wide availability on ordinary smartphones.
Polygenic Risk Scores for Cardiovascular Disease: A Scientific Statement From the American Heart Association
JW O'Sullivan et al, Circulation, July 18, 2022
(Posted: Jul 18, 2022 1PM)
Individuals and their physicians are increasingly presented with polygenic risk scores for cardiovascular conditions in clinical encounters. In this scientific statement, we review the contemporary science, clinical considerations, and future challenges for polygenic risk scores for cardiovascular diseases. We selected 5 cardiometabolic diseases (coronary artery disease, hypercholesterolemia, type 2 diabetes, atrial fibrillation, and venous thromboembolic disease) and response to drug therapy and offer provisional guidance to health care professionals, researchers, policymakers, and patients.
International electronic health record-derived post-acute sequelae profiles of COVID-19 patients
HG Zhang et al, NPJ Digital Medicine, June 29, 2022
(Posted: Jun 29, 2022 7PM)
We leveraged electronic health record (EHR) data from 277 international hospitals representing 414,602 patients with COVID-19, 2.3 million control patients without COVID-19 in the inpatient and outpatient settings, and over 221 million diagnosis codes to systematically identify new-onset conditions enriched among patients with COVID-19 during the post-acute period. Compared to inpatient controls, inpatient COVID-19 cases were at significant risk for angina pectoris (RR 1.30, 95% CI 1.09–1.55), heart failure (RR 1.22, 95% CI 1.10–1.35), cognitive dysfunctions (RR 1.18, 95% CI 1.07–1.31), and fatigue (RR 1.18, 95% CI 1.07–1.30). Relative to outpatient controls, outpatient COVID-19 cases were at risk for pulmonary embolism (RR 2.10, 95% CI 1.58–2.76), venous embolism (RR 1.34, 95% CI 1.17–1.54), atrial fibrillation (RR 1.30, 95% CI 1.13–1.50), type 2 diabetes (RR 1.26, 95% CI 1.16–1.36) and vitamin D deficiency (RR 1.19, 95% CI 1.09–1.30).
Mortality Among Patients With Early-Onset Atrial Fibrillation and Rare Variants in Cardiomyopathy and Arrhythmia Genes.
Yoneda Zachary T et al. JAMA cardiology 2022 5
(Posted: May 13, 2022 8AM)
In this cohort study of 1293 participants diagnosed with AF before 66 years of age, time to death was significantly associated with a disease-associated variant, age at AF diagnosis, and the interaction between age at AF diagnosis and variant status. The findings suggest that among patients with early-onset AF, the presence of a disease-associated rare variant for an inherited cardiomyopathy or arrhythmia syndrome may be associated with an increased risk of mortality.
Association of Pathogenic DNA Variants Predisposing to Cardiomyopathy With Cardiovascular Disease Outcomes and All-Cause Mortality.
Patel Aniruddh P et al. JAMA cardiology 2022 5
(Posted: May 13, 2022 8AM)
In this genetic association study of 9667 participants in the US (Atherosclerosis in Risk Communities [ARIC]) and 49?744 participants in the UK (UK Biobank), a pathogenic or likely pathogenic variant for inherited cardiomyopathy was identified in 0.61% of ARIC participants and 0.73% of UK Biobank participants. These individuals were at 1.7- to 2.1-fold increased risk of heart failure, 2.1- to 2.9-fold increased risk of atrial fibrillation, and 1.5- to 1.7-fold increased risk of all-cause mortality, and they were not reliably identified by imaging. These results suggest that 0.7% of participants harbor a pathogenic variant related to inherited cardiomyopathy and are at increased risk of cardiovascular morbidity and all-cause mortality.
Genetic Testing for Early-Onset Atrial Fibrillation-Is It Time to Personalize Care?
McNally Elizabeth M et al. JAMA cardiology 2022 5
(Posted: May 13, 2022 8AM)
New studies recognize that AF may be the first clinical presentation of carrying a P/LP variant in cardiomyopathic genes. These studies also distinguish that carriers of P/LP cardiomyopathy gene variants have worse long-term outcomes compared with noncarriers. In light of these data, is it time to personalize care for EOAF and incorporate panel-based rare-variant genetic testing into the clinical management framework as is currently recommended for cardiomyopathy? Even with incomplete penetrance, can these genetic variants be incorporated as key risk-enhancing factors to inform a precision approach to screening, prevention, and management of a variety of cardiovascular diseases, including AF?
Implementation of pharmacogenomic clinical decision support for health systems: a cost-utility analysis
S Jiang et al, The PGX journal, April 1, 2022
(Posted: Apr 02, 2022 8AM)
We constructed a cost-effectiveness model to assess the clinical and economic value of a CDS alert program that provides pharmacogenomic (PGx) testing results, compared to no alert program in acute coronary syndrome (ACS) and atrial fibrillation (AF), from a health system perspective. We defaulted that 20% of 500,000 health-system members between the ages of 55 and 65 received PGx testing for CYP2C19 (ACS-clopidogrel) and CYP2C9, CYP4F2 and VKORC1 (AF-warfarin) annually. Clinical events, costs, and quality-adjusted life years (QALYs) were calculated over 20 years with an annual discount rate of 3%. In total, 3169 alerts would be fired. The CDS alert program would help avoid 16 major clinical events and 6 deaths for ACS; and 2 clinical events and 0.9 deaths for AF.
Implantable loop recorder detection of atrial fibrillation to prevent stroke (The LOOP Study): a randomised controlled trial.
Svendsen Jesper H et al. Lancet (London, England) 2021 9
(Posted: Sep 02, 2021 8AM)
In individuals with stroke risk factors, ILR screening resulted in a three-times increase in atrial fibrillation detection and anticoagulation initiation but no significant reduction in the risk of stroke or systemic arterial embolism. These findings might imply that not all atrial fibrillation is worth screening for, and not all screen-detected atrial fibrillation merits anticoagulation.
Social determinants of atrial fibrillation
UR Essien et al, Nat Rev Cardio, June 2, 2021
(Posted: Jun 04, 2021 11AM)
We summarize the contributions of social determinants to the patient experience and outcomes associated with this common condition. We emphasize the relevance of social determinants and their important intersection with atrial fibrillation treatment and outcomes. We identify gaps in the literature and propose future directions for the investigation of social determinants and atrial fibrillation.
Combining Clinical and Polygenic Risk Improves Stroke Prediction Among Individuals with Atrial Fibrillation.
O'Sullivan Jack W et al. Circulation. Genomic and precision medicine 2021 5
(Posted: May 25, 2021 6AM)
Compared with the currently recommended risk tool (CHA2DS2-VASc), the integrated tool significantly improved net reclassification (NRI: 2.3% (95%CI: 1.3% to 3.0%)), and fit (?2 P =0.002). Using this improved tool, >115,000 people with AF would have improved risk classification in the US.
Atrial fibrillation—a complex polygenetic disease
JH Andersen et al, EJHG, December 5, 2020
(Posted: Dec 07, 2020 8AM)
Atrial fibrillation (AF) is the most common type of arrhythmia. Epidemiological studies have documented a substantial genetic component. More than 160 genes have been associated with AF during the last decades. Recent findings challenge our traditional understanding of AF being an electrical disease by implicating atrial cardiomyopathies in its pathogenesis.
Big Data and Atrial Fibrillation: Current Understanding and New Opportunities.
Wang Qian-Chen et al. Journal of cardiovascular translational research 2020 May
(Posted: May 12, 2020 3PM)
Accuracy of Smartphone Camera Applications for Detecting Atrial Fibrillation- A Systematic Review and Meta-analysis
JW O'SUllivan et al, JAMA Network Open, April 3, 2020
(Posted: Apr 05, 2020 8AM)
In this meta-analysis of 10 primary diagnostic accuracy studies with 3852 participants, all applications that used photoplethysmography signals to diagnose AF had high sensitivity and specificity. The modeled positive predictive value for screening an asymptomatic population aged 65 years and older with a history of hypertension was approximately 20% to 40%.
Assessment of a Machine Learning Model Applied to Harmonized Electronic Health Record Data for the Prediction of Incident Atrial Fibrillation
P Tiwari et al, JAMA Network Open, January 17, 2020
(Posted: Jan 20, 2020 8AM)
Can machine learning approaches applied to harmonized electronic health record data identify patients at risk of 6-month incident atrial fibrillation with greater accuracy than standard risk factors? This diagnostic study used electronic health record data from more than 2 million individuals to classify patients diagnosed with incident atrial fibrillation.
Cost-effectiveness of targeted screening for the identification of patients with atrial fibrillation: Evaluation of a machine learning risk prediction algorithm.
Hill Nathan R et al. Journal of medical economics 2019 Dec 1
(Posted: Jan 02, 2020 9AM)
As many cases of atrial fibrillation (AF) are asymptomatic, patients often remain undiagnosed until complications manifest. Risk-prediction algorithms may help to efficiently identify people with undiagnosed AF. This study aimed to assess the cost-effectiveness of targeted screening, informed by a machine learning risk prediction algorithm, to identify patients with AF.
Diagnosing With a Camera From a Distance—Proceed Cautiously and Responsibly
MP Turakhia, JAMA Cardiology, November 2019
(Posted: Nov 28, 2019 9AM)
A new study asks whether video images of the human face can be used to assess pulsatile blood flow and assess for atrial fibrillation. Using a digital camera, the authors recorded 20 individuals with atrial fibrillation and 24 controls. This proof-of-concept study may have bold implications.
Large-Scale Assessment of a Smartwatch to Identify Atrial Fibrillation
MV Perez et al, NEJM, November 13, 2019
(Posted: Nov 14, 2019 8AM)
Optical sensors on wearable devices can detect irregular pulses. The ability of a smartwatch application (app) to identify atrial fibrillation during typical use is unknown. We recruited 419,297 participants over 8 months. Over a median of 117 days of monitoring, 2161 participants (0.52%) received notifications of irregular pulse.
An artificial intelligence-enabled ECG algorithm for the identification of patients with atrial fibrillation during sinus rhythm: a retrospective analysis of outcome prediction
Z Attia et al, The Lancet, August 1, 2019
(Posted: Aug 02, 2019 8AM)
Apple Watch Atrial Fibrillation Study Has High Rate of False Positives
M Terry, Biospace, March 18, 2019
(Posted: Mar 19, 2019 9AM)
Genetics Of Atrial Fibrilation: In Search Of Novel Therapeutic Targets.
Lozano-Velasco Estefanía et al. Cardiovascular & hematological disorders drug targets 2019 Feb
(Posted: Mar 19, 2019 8AM)
Apple Watch Helps Detect AF: Is This the Future?
S Hughes, Medscape, March 16, 2019
(Posted: Mar 19, 2019 7AM)
Giant study shows Apple Watch can spot heart rhythm changes but its far from medical-grade technology
M Herper, Stat News, March 16, 2019
(Posted: Mar 19, 2019 7AM)
Apple Heart Study demonstrates ability of wearable technology to detect atrial fibrillation
Stanford researchers presented preliminary findings from a virtual study that enrolled more than 400,000 participants.
Stanford University, March 16, 2019
(Posted: Mar 19, 2019 7AM)
Association of Thyroid Function Genetic Predictors With Atrial Fibrillation: A Phenome-Wide Association Study and Inverse-Variance Weighted Average Meta-analysis.
Salem Joe-Elie et al. JAMA cardiology 2019 Jan
(Posted: Jan 25, 2019 10AM)
Thyroid Function and the Risk of Atrial Fibrillation
Exploring Potentially Causal Relationships Through Mendelian Randomization
JD Roberts, JAMA Cardiology, January 23, 2019
(Posted: Jan 23, 2019 11AM)
Assessment of the Relationship Between Genetic Determinants of Thyroid Function and Atrial Fibrillation
A Mendelian Randomization Study
C Ellervik et al, JAMA Cardiology, January 23, 2019
(Posted: Jan 23, 2019 11AM)
Keeping the Beat - Researchers Find New Genetic Variants Linked to Atrial Fibrillation, Suggesting New Treatment Targets
S Ktori, GEN News, October 25, 2018
(Posted: Oct 28, 2018 8AM)
Atrial Fibrillation Fact Sheet
CDC Fact Sheet
(Posted: Sep 23, 2018 10AM)
Association Between Family History and Early-Onset Atrial Fibrillation Across Racial and Ethnic Groups
Z Alzaharani et al, JAMA Network Open, September 21, 2018
(Posted: Sep 21, 2018 1PM)
Screening for Atrial Fibrillation With Electrocardiography: Evidence Report and Systematic Review for the US Preventive Services Task Force.
Jonas Daniel E et al. JAMA 2018 Aug (5) 485-498
(Posted: Aug 09, 2018 9AM)
Screening for Atrial Fibrillation With Electrocardiography: US Preventive Services Task Force Recommendation Statement.
et al. JAMA 2018 Aug (5) 478-484
(Posted: Aug 09, 2018 9AM)
Screening for Atrial Fibrillation Comes With Many Snags.
Mandrola John et al. JAMA internal medicine 2018 Aug
(Posted: Aug 09, 2018 9AM)
Multi-ethnic genome-wide association study for atrial fibrillation.
Roselli Carolina et al. Nature genetics 2018 Jun
(Posted: Jun 13, 2018 10AM)
Genetics of atrial fibrillation: an update.
Campbell Hannah M et al. Current opinion in cardiology 2018 Feb
(Posted: Mar 13, 2018 2PM)
Validation of a genetic risk score for atrial fibrillation: A prospective multicenter cohort study
ED Muse et al, PLOS Medicine, Mar 13, 2018
(Posted: Mar 13, 2018 2PM)
Genome-wide association study of 1 million people identifies 111 loci for atrial fibrillation
JB Nielsen et al, BioRXIV, Jan 2018
(Posted: Jan 06, 2018 8PM)
Heritability of Atrial Fibrillation.
Weng Lu-Chen et al. Circulation. Cardiovascular genetics 2017 Dec (6)
(Posted: Jan 06, 2018 8PM)
Gene Therapy for Atrial Fibrillation in Heart Failure.
Arora R et al. Clinical pharmacology and therapeutics 2017 Aug (2) 200-202
(Posted: Sep 24, 2017 6AM)
Genetics of Atrial Fibrillation: State of the Art in 2017.
Fatkin Diane et al. Heart, lung & circulation 2017 Sep (9) 894-901
(Posted: Sep 24, 2017 6AM)
Genomic basis of atrial fibrillation.
Bapat Aneesh et al. Heart (British Cardiac Society) 2017 Sep
(Posted: Sep 24, 2017 6AM)
Association of a Family History of Atrial Fibrillation With Incidence and Outcomes of Atrial Fibrillation: A Population-Based Family Cohort Study.
Chang Shang-Hung et al. JAMA cardiology 2017 Aug (8) 863-870
(Posted: Sep 24, 2017 6AM)
Circulating MicroRNAs as Potential Biomarkers of Atrial Fibrillation.
da Silva Ananília Medeiros Gomes et al. BioMed research international 2017 7804763
(Posted: May 01, 2017 10AM)
Update about atrial fibrillation genetics.
Pérez-Serra Alexandra et al. Current opinion in cardiology 2017 Feb
(Posted: May 01, 2017 10AM)
Genetic Risk Prediction of Atrial Fibrillation.
Lubitz Steven A et al. Circulation 2017 Apr (14) 1311-1320
(Posted: May 01, 2017 10AM)
Proteomics of Atrial Fibrillation- Evolving From a Coarse Understanding to a Fine Phenotype
C Hyman, JAMA Cardiology, March 29, 2017
(Posted: Apr 03, 2017 2PM)
Genetic Investigation Into the Differential Risk of Atrial Fibrillation Among Black and White Individuals
JD Roberts et al, JAMA Cardiology, June 22, 2016
(Posted: Jun 23, 2016 9AM)
The Double Paradox of Atrial Fibrillation in Black Individuals
TS Stamos et al, JAMA Cardiology, June 22, 2016
(Posted: Jun 22, 2016 5PM)
Genetic risk for atrial fibrillation could motivate patient adherence to warfarin therapy: a cost effectiveness analysis.
Shiffman Dov et al. BMC cardiovascular disorders 2015 15(1) 104
(Posted: Oct 06, 2015 5PM)
Universal versus genotype-guided use of direct oral anticoagulants in atrial fibrillation patients: a decision analysis.
You Joyce Hs et al. Pharmacogenomics 2015 Jul 31. 1-12
(Posted: Aug 04, 2015 2PM)
Genetic and clinical risk prediction model for postoperative atrial fibrillation.
Kolek Matthew J et al. Circ Arrhythm Electrophysiol 2015 Feb (1) 25-31
(Posted: Jun 21, 2015 7PM)
Common genetic variants and response to atrial fibrillation ablation.
Shoemaker M Benjamin et al. Circ Arrhythm Electrophysiol 2015 Apr (2) 296-302
(Posted: Jun 21, 2015 7PM)
Common and rare variants in SCN10A modulate the risk of atrial fibrillation.
Jabbari Javad et al. Circ Cardiovasc Genet 2015 Feb (1) 64-73
(Posted: Jun 21, 2015 7PM)
The Role of Pharmacogenetics in Atrial Fibrillation Therapeutics - Is Personalized Therapy in Sight?
Darbar Dawood et al. J. Cardiovasc. Pharmacol. 2015 May 9.
(Posted: Jun 21, 2015 7PM)
The Genetic Basis of Coronary Artery Disease and Atrial Fibrillation: A Search for Disease Mechanisms and Therapeutic Targets.
Neelankavil Jacques et al. J. Cardiothorac. Vasc. Anesth. 2015 Jan 23.
(Posted: Jun 21, 2015 7PM)
Genetics of atrial fibrillation: from families to genomes.
Christophersen Ingrid E et al. J. Hum. Genet. 2015 May 21.
(Posted: Jun 21, 2015 7PM)
Genetic Variants of Potassium Voltage-Gated Channel Genes (KCNQ1, KCNH2, and KCNE1) Affected the Risk of Atrial Fibrillation in Elderly Patients.
Li Li et al. Genet Test Mol Biomarkers 2015 Jun 11.
(Posted: Jun 21, 2015 7PM)
Comparison of Atrial Fibrillation Guidelines.
Overvad Thure Filskov et al. J Gen Intern Med 2015 May 5.
(Posted: Jun 21, 2015 7PM)
Clinical Benefit of American College of Chest Physicians Versus European Society of Cardiology Guidelines for Stroke Prophylaxis in Atrial Fibrillation.
Andrade Ambar A et al. J Gen Intern Med 2015 May 7.
(Posted: Jun 21, 2015 7PM)
Stroke prevention in atrial fibrillation: a systematic review.
Lip Gregory Y H et al. JAMA 2015 May 19. (19) 1950-62
(Posted: Jun 21, 2015 7PM)
Implementing Guidelines: The Cost and Clinical Impact of Anticoagulants in the UK Atrial Fibrillation Population.
Shields Gemma E et al. Appl Health Econ Health Policy 2015 Jun 16.
(Posted: Jun 21, 2015 7PM)
Stroke with atrial fibrillation or atrial flutter: a descriptive population-based study from the Brest stroke registry.
Jannou Virginie et al. BMC Geriatr 2015 (1) 63
(Posted: Jun 21, 2015 7PM)
Find out which genetic conditions and tests are associated with atrial fibrillation
from the Genetic Testing Registry
(Posted: Jun 21, 2015 7PM)
Genetics/Family history is a risk factor for atrial fibrillation
from the Mayo Clinic
(Posted: Jun 21, 2015 7PM)
Arrhythmia
From NHLBI health topic site
(Posted: Jan 01, 2014 0AM)
What Is
An arrhythmia (ah-RITH-me-ah) is a problem with the rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm.
A heartbeat that is too fast is called tachycardia (TAK-ih-KAR-de-ah). A heartbeat that is too slow is called bradycardia (bray-de-KAR-de-ah).
Most arrhythmias are harmless, but some can be serious or even life threatening. During an arrhythmia, the heart may not be able to pump enough blood to the body. Lack of blood flow can damage the brain, heart, and other organs.
Understanding the Heart's Electrical System
To understand arrhythmias, it helps to understand the heart's internal electrical system. The heart's electrical system controls the rate and rhythm of the heartbeat.
With each heartbeat, an electrical signal spreads from the top of the heart to the bottom. As the signal travels, it causes the heart to contract and pump blood.
Each electrical signal begins in a group of cells called the sinus node or sinoatrial (SA) node. The SA node is located in the heart's upper right chamber, the right atrium (AY-tree-um). In a healthy adult heart at rest, the SA node fires off an electrical signal to begin a new heartbeat 60 to 100 times a minute.
From the SA node, the electrical signal travels through special pathways in the right and left atria. This causes the atria to contract and pump blood into the heart's two lower chambers, the ventricles (VEN-trih-kuls).
The electrical signal then moves down to a group of cells called the atrioventricular (AV) node, located between the atria and the ventricles. Here, the signal slows down just a little, allowing the ventricles time to finish filling with blood.
The electrical signal then leaves the AV node and travels along a pathway called the bundle of His. This pathway divides into a right bundle branch and a left bundle branch. The signal goes down these branches to the ventricles, causing them to contract and pump blood to the lungs and the rest of the body.
The ventricles then relax, and the heartbeat process starts all over again in the SA node. (For more information about the heart's electrical system, including detailed animations, go to the Health Topics How the Heart Works article.)
A problem with any part of this process can cause an arrhythmia. For example, in atrial fibrillation (A-tre-al fi-bri-LA-shun), a common type of arrhythmia, electrical signals travel through the atria in a fast and disorganized way. This causes the atria to quiver instead of contract.
Outlook
There are many types of arrhythmia. Most arrhythmias are harmless, but some are not. The outlook for a person who has an arrhythmia depends on the type and severity of the arrhythmia.
Even serious arrhythmias often can be successfully treated. Most people who have arrhythmias are able to live normal, healthy lives.
Other Names
?Dysrhythmia
Atrial Fibrillation
From NHLBI health topic site
(Posted: Jan 01, 2014 0AM)
What Is
Atrial fibrillation (A-tre-al fi-bri-LA-shun), or AF, is the most common type of arrhythmia (ah-RITH-me-ah). An arrhythmia is a problem with the rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm.
AF occurs if rapid, disorganized electrical signals cause the heart's two upper chambers?called the atria (AY-tree-uh)?to fibrillate. The term "fibrillate" means to contract very fast and irregularly.
In AF, blood pools in the atria. It isn't pumped completely into the heart's two lower chambers, called the ventricles (VEN-trih-kuls). As a result, the heart's upper and lower chambers don't work together as they should.
People who have AF may not feel symptoms. However, even when AF isn't noticed, it can increase the risk of stroke. In some people, AF can cause chest pain or heart failure, especially if the heart rhythm is very rapid.
AF may happen rarely or every now and then, or it may become an ongoing or long-term heart problem that lasts for years.
Understanding the Heart's Electrical System
To understand AF, it helps to understand the heart's internal electrical system. The heart's electrical system controls the rate and rhythm of the heartbeat.
With each heartbeat, an electrical signal spreads from the top of the heart to the bottom. As the signal travels, it causes the heart to contract and pump blood.
Each electrical signal begins in a group of cells called the sinus node or sinoatrial (SA) node. The SA node is located in the right atrium. In a healthy adult heart at rest, the SA node sends an electrical signal to begin a new heartbeat 60 to 100 times a minute. (This rate may be slower in very fit athletes.)
From the SA node, the electrical signal travels through the right and left atria. It causes the atria to contract and pump blood into the ventricles.
The electrical signal then moves down to a group of cells called the atrioventricular (AV) node, located between the atria and the ventricles. Here, the signal slows down slightly, allowing the ventricles time to finish filling with blood.
The electrical signal then leaves the AV node and travels to the ventricles. It causes the ventricles to contract and pump blood to the lungs and the rest of the body. The ventricles then relax, and the heartbeat process starts all over again in the SA node.
For more information about the heart's electrical system and detailed animations, go to the Diseases and Conditions Index How the Heart Works article.
Understanding the Electrical Problem in Atrial Fibrillation
In AF, the heart's electrical signals don't begin in the SA node. Instead, they begin in another part of the atria or in the nearby pulmonary veins. The signals don't travel normally. They may spread throughout the atria in a rapid, disorganized way. This can cause the atria to fibrillate.
The faulty signals flood the AV node with electrical impulses. As a result, the ventricles also begin to beat very fast. However, the AV node can't send the signals to the ventricles as fast as they arrive. So, even though the ventricles are beating faster than normal, they aren't beating as fast as the atria.
Thus, the atria and ventricles no longer beat in a coordinated way. This creates a fast and irregular heart rhythm. In AF, the ventricles may beat 100 to 175 times a minute, in contrast to the normal rate of 60 to 100 beats a minute.
If this happens, blood isn't pumped into the ventricles as well as it should be. Also, the amount of blood pumped out of the ventricles to the body is based on the random atrial beats.
The body may get rapid, small amounts of blood and occasional larger amounts of blood. The amount will depend on how much blood has flowed from the atria to the ventricles with each beat.
Most of the symptoms of AF are related to how fast the heart is beating. If medicines or age slow the heart rate, the symptoms are minimized.
AF may be brief, with symptoms that come and go and end on their own. Or, the condition may be ongoing and require treatment. Sometimes AF is permanent, and medicines or other treatments can't restore a normal heart rhythm.
Outlook
People who have AF can live normal, active lives. For some people, treatment can restore normal heart rhythms.
For people who have permanent AF, treatment can help control symptoms and prevent complications. Treatment may include medicines, medical procedures, and lifestyle changes.
Other Names
?A fib
?Auricular fibrillation
Catheter Ablation
From NHLBI health topic site
(Posted: Jan 01, 2014 0AM)
Also known as Cardiac Catheter Ablation
Catheter ablation is a procedure that uses energy to make small scars in your heart tissue to prevent abnormal electrical signals from moving through your heart.
Overview
Radiofrequency (RF) ablation uses high-energy, locally delivered RF signals to make the scars. Cryoablation uses extremely cold temperatures to make the scars. Sometimes, laser light energy is used. Catheter ablation is used to treat certain types of arrhythmias, or irregular heartbeats, that cannot be controlled by medicine or if you have a high risk for ventricular fibrillation (v-fib), sudden cardiac arrest, or atrial fibrillation.
Cardiologists, or doctors who specialize in the heart, will perform catheter ablation in a hospital. You will be awake, but you will receive medicine through an intravenous (IV) line in your arm to relax you during the procedure. Machines will measure your heart?s activity. All types of ablation require cardiac catheterization to place flexible tubes, or catheters, inside your heart to make the scars. Your doctor will clean and numb an area on your arm, groin or upper thigh, or neck before making a small hole in a blood vessel. Your doctor will thread a series of catheters through the blood vessel to the correct place in your heart. An x ray imaging method called fluoroscopy will let your doctor see the catheters as they are moved into your heart. Some catheters have wire electrodes that record and locate the source of your abnormal heartbeats. Your doctor will aim the tip of a special catheter at the small area of heart tissue. A machine will send either RF waves, extremely cold temperatures, or laser light through the catheter to create a scar called the ablation line. This scar forms a barrier that prevents electrical impulses from crossing between the damaged heart tissue to the surrounding healthy tissue. This will stop abnormal electrical signals from traveling to the rest of the heart and causing arrhythmias.
After catheter ablation, your doctor will remove the catheters and close and bandage the opening on your arm, groin, or neck. You may develop a bruise and soreness where the catheters were inserted. You will stay in the hospital for a few hours or overnight. During this time, your heart rate and blood pressure will be monitored. Your movement will be limited to prevent bleeding in the area where the catheters were inserted. You will need a ride home after the procedure because of the medicines or anesthesia you received.
Catheter ablation has some risks, including bleeding, infection, blood vessel damage, heart damage, arrhythmias, and blood clots. There also may be a very slight risk of cancer from radiation used during catheter ablation. Talk to your doctor and the technicians performing the test about whether you are or could be pregnant. If the procedure is not urgent, they may have you wait until after your pregnancy. If it is urgent, the technicians will take extra steps to protect your baby during catheter ablation.
Cardioversion
From NHLBI health topic site
(Posted: Jan 01, 2014 0AM)
Cardioversion is a procedure that uses external electric shocks to restore a normal heart rhythm.
Overview
Cardioversion is called defibrillation when it is done in an emergency to prevent death due to potentially fatal ventricular arrhythmias that can result in sudden cardiac arrest. Alternatively, your doctor can schedule cardioversion as a way to treat arrhythmias in the upper chambers of your heart called atrial fibrillation. If untreated, atrial fibrillation can increase your risk for stroke and heart failure.
Scheduled cardioversion procedures may be done in a hospital or other health care facility by cardiologists, or doctors who specialize in the heart. While the procedure takes only a few minutes, it requires that you arrive a few hours before the procedure. To prepare, you will be given anesthesia through an intravenous (IV) line in your arm to make you fall asleep, and you will have electrodes placed on your chest and possibly your back. These electrodes will be attached to the cardioversion machine. The machine will record your heart?s electrical activity and send the shocks to your heart. When ready, the doctor will send one or more brief, low-energy shocks to your heart to restore a normal rhythm. You will not feel any pain from the shocks.
You will need to stay for a few hours after your procedure. During this time, your health care team will monitor your heart rhythm and blood pressure closely and watch for complications. You will need a ride home because of the medicines or anesthesia you received. You may have some redness or soreness where the electrodes were placed. You also may have slight bruising where the IV line was inserted in your arm.
Although uncommon, cardioversion has some risks. It can cause or worsen life-threatening arrhythmias that will need to be treated. This procedure can cause blood clots to break away and travel from the heart to other tissues or organs and cause a stroke or other problems. Taking anticlotting medicines before and after cardioversion can reduce this risk.
Heart Block
From NHLBI health topic site
(Posted: Jan 01, 2014 0AM)
What Is
Heart block is a problem that occurs with the heart's electrical system. This system controls the rate and rhythm of heartbeats. ("Rate" refers to the number of times your heart beats per minute. "Rhythm" refers to the pattern of regular or irregular pulses produced as the heart beats.)
With each heartbeat, an electrical signal spreads across the heart from the upper to the lower chambers. As it travels, the signal causes the heart to contract and pump blood.
Heart block occurs if the electrical signal is slowed or disrupted as it moves through the heart.
Overview
Heart block is a type of arrhythmia (ah-RITH-me-ah). An arrhythmia is any problem with the rate or rhythm of the heartbeat.
Some people are born with heart block, while others develop it during their lifetimes. If you're born with the condition, it's called congenital (kon-JEN-ih-tal) heart block. If the condition develops after birth, it's called acquired heart block.
Doctors might detect congenital heart block before or after a baby is born. Certain diseases that may occur during pregnancy can cause heart block in a baby. Some congenital heart defects also can cause heart block. Congenital heart defects are problems with the heart's structure that are present at birth. Often, doctors don't know what causes these defects.
Acquired heart block is more common than congenital heart block. Damage to the heart muscle or its electrical system causes acquired heart block. Diseases, surgery, or medicines can cause this damage.
The three types of heart block are first degree, second degree, and third degree. First degree is the least severe, and third degree is the most severe. This is true for both congenital and acquired heart block.
Doctors use a test called an EKG (electrocardiogram) to help diagnose heart block. This test detects and records the heart's electrical activity. It maps the data on a graph for the doctor to review.
Outlook
The symptoms and severity of heart block depend on which type you have. First-degree heart block may not cause any severe symptoms.
Second-degree heart block may result in the heart skipping a beat or beats. This type of heart block also can make you feel dizzy or faint.
Third-degree heart block limits the heart's ability to pump blood to the rest of the body. This type of heart block may cause fatigue (tiredness), dizziness, and fainting. Third-degree heart block requires prompt treatment because it can be fatal.
A medical device called a pacemaker is used to treat third-degree heart block and some cases of second-degree heart block. This device uses electrical pulses to prompt the heart to beat at a normal rate. Pacemakers typically are not used to treat first-degree heart block.
All types of heart block may increase your risk for other arrhythmias, such as atrial fibrillation (A-tre-al fih-brih-LA-shun). Talk with your doctor to learn more about the signs and symptoms of arrhythmias.
Pacemakers
From NHLBI health topic site
(Posted: Jan 01, 2014 0AM)
What Is a Pacemaker
A pacemaker is a small device that's placed in the chest or abdomen to help control abnormal heart rhythms. This device uses electrical pulses to prompt the heart to beat at a normal rate.
Pacemakers are used to treat arrhythmias (ah-RITH-me-ahs). Arrhythmias are problems with the rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm.
A heartbeat that's too fast is called tachycardia (TAK-ih-KAR-de-ah). A heartbeat that's too slow is called bradycardia (bray-de-KAR-de-ah).
During an arrhythmia, the heart may not be able to pump enough blood to the body. This can cause symptoms such as fatigue (tiredness), shortness of breath, or fainting. Severe arrhythmias can damage the body's vital organs and may even cause loss of consciousness or death.
A pacemaker can relieve some arrhythmia symptoms, such as fatigue and fainting. A pacemaker also can help a person who has abnormal heart rhythms resume a more active lifestyle.
Understanding the Heart's Electrical System
Your heart has its own internal electrical system that controls the rate and rhythm of your heartbeat. With each heartbeat, an electrical signal spreads from the top of your heart to the bottom. As the signal travels, it causes the heart to contract and pump blood.
Each electrical signal normally begins in a group of cells called the sinus node or sinoatrial (SA) node. As the signal spreads from the top of the heart to the bottom, it coordinates the timing of heart cell activity.
First, the heart's two upper chambers, the atria (AY-tree-uh), contract. This contraction pumps blood into the heart's two lower chambers, the ventricles (VEN-trih-kuls). The ventricles then contract and pump blood to the rest of the body. The combined contraction of the atria and ventricles is a heartbeat.
For more information about the heart's electrical system and detailed animations, go to the Health Topics How the Heart Works article.
Overview
Faulty electrical signaling in the heart causes arrhythmias. Pacemakers use low-energy electrical pulses to overcome this faulty electrical signaling. Pacemakers can:
?Speed up a slow heart rhythm.
?Help control an abnormal or fast heart rhythm.
?Make sure the ventricles contract normally if the atria are quivering instead of beating with a normal rhythm (a condition called atrial fibrillation).
?Coordinate electrical signaling between the upper and lower chambers of the heart.
?Coordinate electrical signaling between the ventricles. Pacemakers that do this are called cardiac resynchronization therapy (CRT) devices. CRT devices are used to treat heart failure.
?Prevent dangerous arrhythmias caused by a disorder called long QT syndrome.
Pacemakers also can monitor and record your heart's electrical activity and heart rhythm. Newer pacemakers can monitor your blood temperature, breathing rate, and other factors. They also can adjust your heart rate to changes in your activity.
Pacemakers can be temporary or permanent. Temporary pacemakers are used to treat short-term heart problems, such as a slow heartbeat that's caused by a heart attack, heart surgery, or an overdose of medicine.
Temporary pacemakers also are used during emergencies. They might be used until your doctor can implant a permanent pacemaker or until a temporary condition goes away. If you have a temporary pacemaker, you'll stay in a hospital as long as the device is in place.
Permanent pacemakers are used to control long-term heart rhythm problems. This article mainly discusses permanent pacemakers, unless stated otherwise.
Doctors also treat arrhythmias with another device called an implantable cardioverter defibrillator (ICD). An ICD is similar to a pacemaker. However, besides using low-energy electrical pulses, an ICD also can use high-energy pulses to treat life-threatening arrhythmias.
Wolff-Parkinson-White Syndrome
From NHLBI health topic site
(Posted: Jan 01, 2014 0AM)
Wolff-Parkinson-White (WPW) syndrome is a condition that causes an irregular heart rhythm, or arrhythmia.
Overview
Electrical signals in the heart usually travel along certain pathways to tell the heart to beat regularly. People with WPW syndrome are born with an extra electrical pathway that changes the way these signals travel.
Symptoms of the arrhythmia that occur in WPW syndrome may include palpitations, chest pain or tightness, shortness of breath, dizziness, or faintness. Some people experience few to no symptoms. Others may have symptoms twice a week or more often.
Most people with WPW syndrome do not have any other heart problems. Sometimes WPW syndrome is diagnosed during a routine test for heart disease, such as an electrocardiogram. Your doctor may recommend testing for WPW syndrome if you have atrial fibrillation, known as A-fib, or a family history of WPW syndrome. You may be asked to wear a Holter or event monitor that records your heart?s electrical activity while you do your normal activities.
If your doctor diagnoses you with WPW syndrome, you may need medicine to control or prevent a fast heartbeat. If medicine does not work, you may need an electrical shock to the heart to restore its rhythm. Catheter ablation is another treatment that can cure WPW syndrome in most people. If untreated, WPW syndrome can cause the heart to beat much faster than it should, which is called tachycardia, and it can increase the risk of sudden cardiac death.
Familial atrial fibrillation
From NCATS Genetic and Rare Diseases Information Center
(Posted: Jan 01, 2011 0AM)
