An organized and directed approach to a thorough review of evidence has resulted in the production of clinical practice guidelines that assist clinicians in selecting the best management strategy for ...an individual patient. ...clinical practice guidelines can provide a foundation for other applications, such as performance measures, appropriate use criteria, and both quality improvement and clinical decision support tools. Therapies not available in the United States are discussed in the text without a specific COR.\nACC indicates American College of Cardiology; AHA, American Heart Association; AIG, Association of International Governors; DSMB, data safety monitoring board; EP, electrophysiology; HF, heart failure; HHS, Health and Human Services; HRS, Heart Rhythm Society; ICD, implantable cardioverter-defibrillator; PI, principal investigator; STOP-AF, Sustained Treatment Of Paroxysmal Atrial Fibrillation; STS, Society of Thoracic Surgeons; UCLA, University of California, Los Angeles; USUHS, Uniformed Services University of the Health Sciences; UT, University of Texas; VA, Veterans Affairs; and VCU, Virginia Commonwealth University.
Abstract Previous studies have shown several metabolic biomarkers to be associated with prevalent and incident atrial fibrillation (AF), but the results have not been replicated. We investigated ...metabolite profiles of 2,458 European ancestry participants from the Framingham Heart Study without AF at the index exam and followed them for 10 years for new-onset AF. Amino acids, organic acids, lipids, and other plasma metabolites were profiled by liquid chromatography-tandem mass spectrometry using fasting plasma samples. We conducted Cox proportional hazard analyses for association between metabolites and new-onset AF. We performed hypothesis generating analysis to identify novel metabolites and hypothesis testing analysis to confirm the previously reported associations between metabolites and AF. Mean age was 55.1±9.9 years, and 53% were women. Incident AF developed in 156 participants (6.3%) in 10 years of follow-up. A total of 217 metabolites were examined, consisting of 54 positively charged metabolites, 59 negatively charged metabolites, and 104 lipids. None of the 217 metabolites met our a priori specified Bonferroni corrected level of significance in the multivariable analyses. We were unable replicate previous results demonstrating associations between metabolites that we had measured and AF. In conclusion, in our metabolomics approach, none of the metabolites we tested were significantly associated with the risk of future AF.
Summary Background Comprehensive long-term data on atrial fibrillation trends in men and women are scant. We aimed to provide such data through analysis of the Framingham cohort over 50 years. ...Methods We investigated trends in incidence, prevalence, and risk factors for atrial fibrillation and its association with stroke and mortality after onset in 9511 participants enrolled in the Framingham Heart Study between 1958 and 2007. We analysed trends within 10 year groups (1958–67, 1968–77, 1978–87, 1988–97, and 1998–2007), stratified by sex. Findings During 50 years of observation (202 417 person-years), 1544 cases of new-onset atrial fibrillation occurred (of whom 723 47% were women). Between 1958–67 and 1998–2007, age-adjusted prevalence of atrial fibrillation quadrupled from 20·4 to 96·2 cases per 1000 person-years in men and from 13·7 to 49·4 cases per 1000 person-years in women; age-adjusted incidence increased from 3·7 to 13·4 new cases per 1000 person-years in men and from 2·5 to 8·6 new cases per 1000 person-years in women (ptrend <0·0001 for all comparisons). For atrial fibrillation diagnosed by electrocardiograph (ECG) during routine Framingham examinations, age-adjusted prevalence per 1000 person-years increased (12·6 in 1958–67 to 25·7 in 1998–2007 in men, ptrend =0·0007; 8·1 to 11·8 in women, ptrend =0·009). However, age-adjusted incidence of atrial fibrillation by Framingham Heart Study ECGs did not change significantly with time. Although the prevalence of most risk factors changed over time, their associated hazards for atrial fibrillation changed little. Multivariable-adjusted proportional hazards models revealed a 74% (95% CI 50–86%) decrease in stroke (hazards ratio HR 3·77, 95% CI 1·98–7·20 in 1958–1967 compared with 1998–2007; ptrend =0·0001) and a 25% (95% CI −3–46%) decrease in mortality (HR 1·34, 95% CI 0·97–1·86 in 1958–1967 compared with 1998–2007; ptrend =0·003) in 20 years following atrial fibrillation onset. Interpretation Trends of increased incidence and prevalence of atrial fibrillation in the community were probably partly due to enhanced surveillance. Measures are needed to enhance early detection of atrial fibrillation, through increased awareness coupled with targeted screening programmes and risk factor-specific prevention. Funding NIH, NHLBI, NINDS, Deutsche Forschungsgemeinschaft.
Background Galectin 3 (Gal-3) is a potential mediator of cardiac fibrosis, and Gal-3 concentrations predict incident heart failure. The same mechanisms that lead to cardiac fibrosis in heart failure ...may influence development of atrial fibrosis and atrial fibrillation (AF). We examined the association of Gal-3 and incident AF in the community. Methods Plasma Gal-3 concentrations were measured in 3,306 participants of the Framingham Offspring cohort who attended the sixth examination cycle (1995-1998, mean age 58 years, 54% women). Cox proportional hazards regression models were used to assess the association of baseline Gal-3 concentrations and incident AF. Results Over a median follow-up period of 10 years, 250 participants developed incident AF. Crude incidence rates of AF by increasing sex-specific Gal-3 quartiles were 3.7%, 5.9%, 9.1%, and 11.5% (log-rank test P < .0001). In age- and sex-adjusted analyses, each 1-SD increase in loge -Gal-3 was associated with a 19% increased hazard of incident AF (hazard ratio 1.19, 95% CI 1.05-1.36, P = .009). This association was not significant after adjustment for traditional clinical AF risk factors (hazard ratio 1.12, 95% CI 0.98-1.28, P = .10). Conclusion Higher circulating Gal-3 concentrations were associated with increased risk of developing AF over the subsequent 10 years in age- and sex-adjusted analyses but not after accounting for other traditional clinical AF risk factors. Our results do not support a role for Gal-3 in AF risk prediction. Further studies are needed to evaluate whether Gal-3 plays a role in the development of AF substrate similar to HF.
Results on the association between P-wave duration and the risk of atrial fibrillation (AF) are conflicting.
The purpose of this study was to obtain a detailed description of the relationship between ...P-wave duration and the risk of AF.
Using computerized analysis of electrocardiograms from a large primary care population, we evaluated the association between P-wave duration and the risk of AF. Secondary end-points were death from cardiovascular causes and putative ischemic stroke. Data on drug use, comorbidity, and outcomes were collected from administrative registries.
A total of 285,933 individuals were included. During median follow-up period of 6.7 years, 9550 developed AF, 9371 died of a cardiovascular cause, and 8980 had a stroke. Compared with the reference group (100-105 ms), individuals with very short (≤89 ms; hazard ratio HR 1.60, 95% confidence interval CI 1.41-1.81), intermediate (112-119 ms; HR 1.22, 95% CI 1.13-1.31), long (120-129 ms; HR 1.50, 95% CI 1.39-1.62), and very long P-wave duration (≥130 ms; HR 2.06, 95% CI 1.89-2.23) had an increased risk of incident AF. With respect to death from cardiovascular causes, we found an increased risk for very short (≤89 ms; HR 1.20, 95% CI 1.06-1.34), long (120-129 ms; HR 1.11, 95% CI 1.04-1.19), and very long P-wave duration (≥130 ms; HR 1.30, 95% CI 1.21-1.40) compared with the reference group (106-111 ms). Similar but weaker associations were found between P-wave duration and the risk of putative ischemic stroke.
In a large primary care population we found both short and long P-wave duration to be robustly associated with an increased risk of AF.
Long-term risk prediction is a priority for the prevention of atrial fibrillation (AF). P wave indices are electrocardiographic measurements describing atrial conduction. The role of P wave indices ...in the prospective determination of AF and mortality risk has had limited assessment. We quantified by digital caliper the P wave indices of maximum duration and dispersion in 1,550 Framingham Heart Study participants ≥60 years old (58% women) from single-channel electrocardiograms recorded from 1968 through 1971. We examined the association of selected P wave indices and long-term outcomes using Cox proportional hazards regression incorporating age, gender, body mass index, systolic blood pressure, treatment for hypertension, significant murmur, heart failure, and PR interval. Over a median follow-up of 15.8 years (range 0 to 38.7), 359 participants developed AF and 1,525 died. Multivariable-adjusted hazard ratios (HRs) per SD increase in maximum P wave duration were 1.15 (95% confidence interval CI 0.90 to 1.47, p = 0.27) for AF and 1.02 (95% CI 0.96 to 1.08, p = 0.18) for mortality. The upper 5% of P wave maximum duration had a multivariable-adjusted HR of 2.51 (95% CI 1.13 to 5.57, p = 0.024) for AF and an HR of 1.11 (95% CI 0.87 to 1.40, p = 0.20) for mortality. We found no significant associations between P wave dispersion with incidence of AF or mortality. In conclusion, maximum P wave duration at the upper fifth percentile was associated with long-term AF risk in an elderly community-based cohort. P wave duration is an electrocardiographic endophenotype for AF.
MicroRNAs (miRNAs) are associated with cardiovascular disease and control gene expression and are detectable in the circulation.
The purpose of this study was to test the hypothesis that circulating ...miRNAs may be associated with atrial fibrillation (AF).
Using a prospective study design powered to detect subtle differences in miRNAs, we quantified plasma expression of 86 miRNAs by high-throughput quantitative reverse transcriptase-polymerase chain reaction in 112 participants with AF and 99 without AF. To examine parallels between cardiac and plasma miRNA profiles, we quantified atrial tissue and plasma miRNA expression using quantitative reverse transcriptase-polymerase chain reaction in 31 participants undergoing surgery. We also explored the hypothesis that lower AF burden after ablation would be reflected in the circulating blood pool by examining change in plasma miRNAs after AF ablation (n = 47).
Mean age of the cohort was 59 years; 58% of participants were men. Plasma miRs-21 and 150 were 2-fold lower in participants with AF than in those without AF after adjustment (P ≤.0006). Plasma levels of miRs-21 and 150 also were lower in participants with paroxysmal AF than in those with persistent AF (P <.05). Expression of miR-21, but not of miR-150, was lower in atrial tissue from patients with AF than in those without AF (P <.05). Plasma levels of miRs-21 and 150 increased 3-fold after AF ablation (P ≤.0006).
Cardiac miRs-21 and 150 are known to regulate genes implicated in atrial remodeling. Our findings show associations between plasma miRs-21 and 150 and AF, suggesting that circulating miRNAs can provide insights into cardiac gene regulation.
Atrial fibrillation (AF) is common and increases stroke risk and mortality. Many knowledge gaps remain with respect to practice patterns and outcomes. Electronic medical records (EMRs) may serve as ...powerful research tools if AF status can be properly ascertained. We sought to develop an algorithm for identifying subjects with and without AF in the EMR and compare it to previous methods. Using a hospital network EMR (n = 5,737,846), we randomly selected 8,200 subjects seen at a large academic medical center in January 2014 to derive and validate 7 AF classification schemas (4 cases and 3 controls) to construct a composite AF algorithm. In an independent sample of 172,138 subjects, we compared this algorithm against published AF classification methods. In total, we performed manual adjudication of AF in 700 subjects. Three AF schemas (AF1, AF2, and AF4) achieved positive predictive value (PPV) >0.9. Two control schemas achieved PPV >0.9 (control 1 and control 3). A combination algorithm AF1, AF2, and AF4 (PPV 88%; 8.2% classified) outperformed published classification methods including >1 outpatient International Statistical Classification of Diseases, Ninth Revision code or 1 outpatient code with an electrocardiogram demonstrating AF (PPV 82%; 5.9% classified), ≥1 inpatient International Statistical Classification of Diseases, Ninth Revision code or electrocardiogram demonstrating AF (PPV 88%; 6.1% classified), or the intersection of these (PPV 84%; 7.4% classified). When applied simultaneously, the case and control algorithms classified 98.4% of the cohort with zero disagreement. In conclusion, we derived a parsimonious and portable algorithm to identify subjects with and without AF with high sensitivity. If broadly applied, this algorithm can provide optimal power for EMR-based AF research.
MicroRNA (miRNA) expression in atrial tissue has been implicated in pathologic susceptibility to atrial fibrillation (AF). Nevertheless, data on how circulating levels relate to AF are limited.
The ...purpose of this study was to test the hypothesis that circulating miRNAs are associated with AF.
Among 2445 Framingham Heart Study Offspring participants, we measured the expression of 385 circulating whole blood miRNAs by high-throughput quantitative reverse transcriptase polymerase chain reaction. We related miRNA levels with prevalent and new-onset AF.
Mean age of the cohort was 66.3 ± 8.9 years, and 56% were women; 153 participants had clinically apparent AF at baseline, and 107 developed AF during median follow-up of 5.4 years. miRNA-328 (miR-328) expression was lower among participants with prevalent AF (8.76 cycle threshold) compared to individuals with no AF (7.75 cycle threshold, P <.001). The association between miR-328 and prevalent AF persisted after adjustment for age, sex, and technical covariates (odds ratio 1.21, P = 1.8 × 10(-4)) but was attenuated in analyses adjusting for clinical AF risk factors (odds ratio 1.14, P = .017). In contrast to the associations between miR-328 and prevalent AF, none of the circulating miRNAs were associated with incident AF.
Circulating levels of miR-328, a miRNA known to promote atrial electrical remodeling by reducing L-type Ca(2+) channel density, were associated with prevalent AF. Adjustment for risk factors that promote atrial remodeling, including hypertension, attenuated the association between miR-328 and AF, potentially implicating miR-328 as a potential mediator of atrial remodeling and AF vulnerability.
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