Echocardiographic Measures of Cardiac Structure and Function Are Associated with Risk of Atrial Fibrillation in Blacks: The Atherosclerosis Risk in Communities (ARIC) Study

BackgroundSeveral studies have examined the link between atrial fibrillation (AF) and various echocardiographic measures of cardiac structure and function in whites and other racial groups but not in blacks. Exploring AF risk factors in blacks is important given that the lower incidence of AF in this racial group despite higher risk factors, is not completely explained.MethodsWe examined the association of echocardiographic measures with AF incidence in 2283 blacks (64.5% women, mean age 58.8 years) free of diagnosed AF and enrolled in the Jackson cohort of Atherosclerosis Risk in Communities (ARIC) study, a prospective study of cardiovascular disease. Echocardiography was performed in 1993–1995, and incident AF was determined by electrocardiograms at a follow-up study exam, hospitalization discharge codes and death certificates through the end of 2009. Cox proportional hazards regression was used to estimate hazard ratios and 95% confidence intervals for AF associated with the echocardiographic measures, adjusting for age, sex, and known AF risk factors.ResultsDuring an average follow-up of 13.5 years, 191 (8.4%) individuals developed AF. Left ventricular (LV) internal diameter 2-D (diastole) and percent fractional shortening of LV diameter displayed a U-shaped relationship with risk of AF, while left atrial diameter displayed a J-shaped nonlinear association. LV mass index was associated positively with AF. E/A ratio 1.5 and ejection fraction (EF <50%) were also associated with higher AF risk. These measures improved risk stratification for AF in addition to traditional risk factors, although not significantly {C-statistic of 0.767 (0.714–0.819) vs. 0.744 (0.691–0.797)}.ConclusionsIn a community-based population of blacks, echocardiographic measures of cardiac structure and function are significantly associated with an increased risk of AF

Rationale and Design of a Multicenter Echocardiographic Study to Assess the Relationship Between Cardiac Structure and Function and Heart Failure Risk in a Biracial Cohort of Community-Dwelling Elderly Persons: The Atherosclerosis Risk in Communities Study

Heart failure (HF) is an important public health concern particularly among persons over 65 years of age. Women and African Americans are critically understudied populations that carry a sizeable portion of the HF burden. Limited normative and prognostic data exist regarding measures of cardiac structure, diastolic function, and novel measures of systolic deformation in older adults living in the community

Usefulness of N-terminal Pro–brain Natriuretic Peptide and Myocardial Perfusion in Asymptomatic Adults (from&nbsp;the Multi-Ethnic Study of Atherosclerosis)

This study sought to investigate the relation between myocardial perfusion and N-terminal pro-brain natriuretic peptide (NT-proBNP) in asymptomatic adults without overt coronary artery disease. NT-proBNP is a cardiac neurohormone secreted from the ventricles in response to ventricular volume expansion and pressure overload and may also be elevated in the setting of reduced myocardial perfusion. We hypothesized that reduced myocardial perfusion reserve (MPR) would be associated with elevated NT-proBNP in participants free of overt cardiovascular disease. MPR was measured by cardiac magnetic resonance, before and after adenosine infusion, in 184 MESA participants (mean age 60 ± 10.4, 58% white, 42% Hispanic, 44% women) without overt cardiovascular disease. MPR was modeled as hyperemic myocardial blood flow (MBF) adjusted for MBF at rest. A linear regression analysis, adjusted for demographics, established cardiovascular risk factors, left ventricular mass, coronary calcium score, body mass index, and medications, was used to determine the association between MPR and NT-proBNP. Participants with low hyperemic MBF were more likely to be older, male, diabetic, and have higher blood pressure and higher coronary artery calcium score. Mean hyperemic MBF was 3.04 ± 0.829 ml/min/g. MPR was inversely associated with NT-proBNP levels. In a fully adjusted model, every 1-SD decrement in MPR was associated with a 21% increment in NT-proBNP (p = 0.04). In conclusion, MPR is inversely associated with NT-proBNP level in this cross-sectional study of asymptomatic adults free of overt coronary artery disease, suggesting that higher NT-proBNP levels may reflect subclinical myocardial microvascular dysfunction

Contemporary Assessment of Left Ventricular Diastolic Function in Older Adults:The Atherosclerosis Risk in Communities Study

BACKGROUND: While age-associated changes in LV diastolic function are well-recognized, limited data exist characterizing measures of diastolic function in older adults, including both reference ranges reflecting the older adult population and prognostically relevant values for incident HF, as well as their associations with circulating biomarkers of heart failure (HF) risk. METHODS: Among 5,801 elderly participants in the Atherosclerosis Risk in Communities (ARIC) study (age range 67–90, mean age 76 ± 5, 42% male, 21% black), we determined the continuous association of diastolic measures (TDI e’, E/e’, and left atrial size) with concomitant NT-proBNP and subsequent HF hospitalization or death. We also determined sex-specific 10(th) and 90(th) percentile limits for these measures using quantile regression in 401 participants free of prevalent cardiovascular disease and risk factors. RESULTS: Each measure of diastolic function was robustly associated with NT-proBNP and incident HF or death. ARIC-based reference limits for TDI e’ (4.6 and 5.2 cm/sec for septal and lateral TDI e’, respectively) were substantially lower than guideline cutpoints (7 and 10 cm/sec, respectively), while E/e’ and LA size demonstrated good agreement with guideline cutpoints. TDI e’ was non-linearly associated with incident HF or death, with inflection points for risk supportive of ARIC-based limits. ARIC-based limits for diastolic function improved risk discrimination over guideline-based cutpoints based on the IDI (p<0.001) and continuous NRI (p<0.001), reclassifying 42% of the study population as having normal diastolic function. We replicate these findings in the Copenhagen City Heart Study. Using these limits, 46% had normal diastolic function and were at low risk of HF hospitalization or death (1%/year over a mean 1.7 year follow-up), 49% had 1 or 2 abnormal measures and were at intermediate risk (2.4%/year), and all 3 diastolic measures were abnormal in 5% who were at high risk (7.5%/year). CONCLUSIONS: Our findings suggest that LV longitudinal relaxation velocity declines as a part of healthy aging and is largely prognostically benign. The use of age-based normative values when considering an elderly population improves the risk discrimination of diastolic measures for incident HF or death

Hazard ratios (HR) and 95% confidence intervals (CI) for the association of echocardiographic parameters in quintiles with time to incident atrial fibrillation (AF), ARIC Jackson Cohort, 1993–2009.

<p><b>*</b> Linear trend in quintile number.</p>†<p>Model 1 - adjusted for age and sex.</p>‡<p>Model 2 – adjusted for Model 1 + CHARGE risk score.</p><p>Hazard ratios (HR) and 95% confidence intervals (CI) for the association of echocardiographic parameters in quintiles with time to incident atrial fibrillation (AF), ARIC Jackson Cohort, 1993–2009.</p

Baseline characteristics with incident atrial fibrillation (AF) events through 2009 follow-up, Atherosclerosis Risk in Communities Study Jackson Cohort, 1993–1995.

<p><b>* Data given as mean±SD or n (%).</b></p><p>Baseline characteristics with incident atrial fibrillation (AF) events through 2009 follow-up, Atherosclerosis Risk in Communities Study Jackson Cohort, 1993–1995.</p

Kaplan-Meier curves for selected echocardiographic parameters, Atherosclerosis Risk in Communities Study Jackson Cohort, 1993–2009.

<p>A: Left Atrial Diameter. B: Left Ventricular Diameter (Diastole). C: Left Ventricular Mass Index (g/m²). D: Left Ventricular Ejection Fraction. E: E/A Ratio. F: % Fractional Shortening of the Left Ventricular Diameter.</p

Inclusion and exclusion criteria, Atherosclerosis Risk in Communities Study Jackson Cohort, 1993–1995.

<p>Inclusion and exclusion criteria, Atherosclerosis Risk in Communities Study Jackson Cohort, 1993–1995.</p