Atrial Fibrillation Begets Heart Failure and Vice Versa: Temporal Associations and Differences in Preserved Versus Reduced Ejection Fraction.

BACKGROUND: Atrial fibrillation (AF) and heart failure (HF) frequently coexist and together confer an adverse prognosis. The association of AF with HF subtypes has not been well described. We sought to examine differences in the temporal association of AF and HF with preserved versus reduced ejection fraction. METHODS AND RESULTS: We studied Framingham Heart Study participants with new-onset AF or HF between 1980 and 2012. Among 1737 individuals with new AF (mean age, 75±12 years; 48% women), more than one third (37%) had HF. Conversely, among 1166 individuals with new HF (mean age, 79±11 years; 53% women), more than half (57%) had AF. Prevalent AF was more strongly associated with incident HF with preserved ejection fraction (multivariable-adjusted hazard ratio [HR], 2.34; 95% confidence interval [CI], 1.48-3.70; no AF as referent) versus HF with reduced ejection fraction (HR, 1.32; 95% CI, 0.83-2.10), with a trend toward difference between HF subtypes (P for difference=0.06). Prevalent HF was associated with incident AF (HR, 2.18; 95% CI, 1.26-3.76; no HF as referent). The presence of both AF and HF portended greater mortality risk compared with neither condition, particularly among individuals with new HF with reduced ejection fraction and prevalent AF (HR, 2.72; 95% CI, 2.12-3.48) compared with new HF with preserved ejection fraction and prevalent AF (HR, 1.83; 95% CI, 1.41-2.37; P for difference=0.02). CONCLUSIONS: AF occurs in more than half of individuals with HF, and HF occurs in more than one third of individuals with AF. AF precedes and follows HF with both preserved and reduced ejection fraction, with some differences in temporal association and prognosis. Future studies focused on underlying mechanisms of these dual conditions are warranted.

Galectin-3 Is Associated with Restrictive Lung Disease and Interstitial Lung Abnormalities.

RATIONALE: Galectin-3 (Gal-3) has been implicated in the development of pulmonary fibrosis in experimental studies, and Gal-3 levels have been found to be elevated in small studies of human pulmonary fibrosis. OBJECTIVES: We sought to study whether circulating Gal-3 concentrations are elevated early in the course of pulmonary fibrosis. METHODS: We examined 2,596 Framingham Heart Study participants (mean age, 57 yr; 54% women; 14% current smokers) who underwent Gal-3 assessment using plasma samples and pulmonary function testing between 1995 and 1998. Of this sample, 1,148 underwent subsequent volumetric chest computed tomography. MEASUREMENTS AND MAIN RESULTS: Higher Gal-3 concentrations were associated with lower lung volumes (1.4% decrease in percentage of predicted FEV1 per 1 SD increase in log Gal-3; 95% confidence interval [CI], 0.8-2.0%; P < 0.001; 1.2% decrease in percentage of predicted FVC; 95% CI, 0.6-1.8%; P < 0.001) and decreased diffusing capacity of the lung for carbon monoxide (2.1% decrease; 95% CI, 1.3-2.9%; P < 0.001). These associations remained significant after multivariable adjustment (P ≤ 0.008 for all). Compared with the lowest quartile, participants in the highest Gal-3 quartile were more than twice as likely to have interstitial lung abnormalities visualized by computed tomography (multivariable-adjusted odds ratio, 2.67; 95% CI, 1.49-4.76; P < 0.001). CONCLUSIONS: Elevated Gal-3 concentrations are associated with interstitial lung abnormalities coupled with a restrictive pattern, including decreased lung volumes and altered gas exchange. These findings suggest a potential role for Gal-3 in early stages of pulmonary fibrosis.

Association of Age, Sex, Body Size and Ethnicity with Electrocardiographic Values in Community-based Older Asian Adults.

BACKGROUND: Existing electrocardiographic (ECG) reference values were derived in middle-aged Caucasian adults. We aimed to assess the association of age, sex, body size and ethnicity on ECG parameters in a multi-ethnic Asian population. METHODS: Resting 12-lead ECG and anthropometric measurements were performed in a community-based cohort of 3777 older Asians (age 64.7±9.1 years, 1467 men, 88.8% Chinese, 7.7% Malay, 3.5% Indian, body mass index [BMI] 24.0±3.9kg/m(2)). RESULTS: Men had longer PR interval, wider QRS, shorter QTc interval and taller SV3. In both sexes, older age was associated with longer PR interval, wider QRS, larger R aVL and more leftward QRS axis, while higher BMI was associated with longer PR interval, wider QRS, larger RaVL and more negative QRS axis. There were significant inter-ethnic differences in QRS duration among men, as well as in PR and QTc intervals among women (all adjusted p<0.05). Findings were similar in a healthy subset of 1158 adults (age 61.2±9.1 years, 365 men) without cardiovascular risk factors. CONCLUSIONS: These first community-based ECG data in multi-ethnic older Asians highlight the independent effects of age, sex, body size and ethnicity on ECG parameters.

The Singapore Heart Failure Outcomes and Phenotypes (SHOP) study and Prospective Evaluation of Outcome in Patients with Heart Failure with Preserved Left Ventricular Ejection Fraction (PEOPLE) study: rationale and design.

BACKGROUND: Heart failure (HF) with preserved ejection fraction (EF) accounts for a substantial proportion of cases of HF, and to date no treatments have clearly improved outcome. There are also little data comparing HF cohorts of differing ethnicity within the Asia-Pacific region. METHODS: The Singapore Heart Failure Outcomes and Phenotypes (SHOP) study and Prospective Evaluation of Outcome in Patients with Heart Failure with Preserved Left Ventricular Ejection Fraction (PEOPLE) study are parallel prospective studies using identical protocols to enroll patients with HF across 6 centers in Singapore and 4 in New Zealand. The objectives are to determine the relative prevalence, characteristics, and outcomes of patients with HF and preserved EF (EF ≥50%) compared with those with HF and reduced EF, and to determine initial data on ethnic differences within and between New Zealand and Singapore. Case subjects (n = 2,500) are patients hospitalized with a primary diagnosis of HF or attending outpatient clinics for management of HF within 6 months of HF decompensation. Control subjects are age- and gender-matched community-based adults without HF from Singapore (n = 1,250) and New Zealand (n = 1,073). All participants undergo detailed clinical assessment, echocardiography, and blood biomarker measurements at baseline, 6 weeks, and 6 months, and are followed over 2 years for death or hospitalization. Substudies include vascular assessment, cardiopulmonary exercise testing, retinal imaging, and cardiac magnetic resonance imaging. CONCLUSIONS: The SHOP and PEOPLE studies are the first prospective multicenter studies defining the epidemiology and interethnic differences among patients with HF in the Asia-Oceanic region, and will provide unique insights into the pathophysiology and outcomes for these patients.

The association of chronic kidney disease and microalbuminuria with heart failure with preserved vs. reduced ejection fraction.

AIMS: Chronic kidney disease (CKD) and microalbuminuria are associated with incident heart failure (HF), but their relative contributions to HF with preserved vs. reduced EF (HFpEF and HFrEF) are unknown. We sought to evaluate the associations of CKD and microalbuminuria with incident HF subtypes in the community-based Framingham Heart Study (FHS). METHODS AND RESULTS: We defined CKD as glomerular filtration rate <60 mL/min/1.73 m2 , and microalbuminuria as a urine albumin to creatinine ratio (UACR) ≥17 mg/g in men and ≥25 mg/g in women. We observed 754 HF events (324 HFpEF/326 HFrEF/104 unclassified) among 9889 FHS participants with serum creatinine measured (follow-up 13 ± 4 years). In Cox models adjusted for clinical risk factors, CKD (prevalence = 9%) was associated with overall HF [hazard ratio (HR) 1.24, 95% confidence interval (CI) 1.01-1.51], but was not significantly associated with individual HF subtypes. Among 2912 individuals with available UACR (follow-up 15 ± 4 years), 192 HF events (91 HFpEF/93 HFrEF/8 unclassified) occurred. Microalbuminuria (prevalence = 17%) was associated with a higher risk of overall HF (HR 1.71, 95% CI 1.25-2.34) and HFrEF (HR 2.10, 95% CI 1.35-3.26), but not HFpEF (HR 1.26, 95% CI 0.78-2.03). In cross-sectional analyses, microalbuminuria was associated with LV systolic dysfunction (odds ratio 3.19, 95% CI 1.67-6.09). CONCLUSIONS: Microalbuminuria was associated with incident HFrEF prospectively, and with LV systolic dysfunction cross-sectionally in a community-based sample. In contrast, CKD was modestly associated with overall HF but not differentially associated with HFpEF vs. HFrEF. The mechanisms responsible for the relationship of microalbuminuria to future development of HFrEF warrant further investigation.

Racial Differences in Electrocardiographic Characteristics and Prognostic Significance in Whites Versus Asians.

BACKGROUND: Racial differences in electrocardiographic (ECG) characteristics and prognostic significance among Whites and Asians are not well described. METHODS AND RESULTS: We studied 2677 White Framingham Heart Study participants (57% women) and 2972 Asian (64% women) Singapore Longitudinal Aging Study participants (mean age 66 years in both) free of myocardial infarction or heart failure. Racial differences in ECG characteristics and effect on mortality were assessed. In linear regression models, PR interval was longer in Asians compared with Whites (multivariable-adjusted ß±SE 5.0±1.4 ms in men and 6.6±0.9 ms in women, both P<0.0006). QT interval was shorter in Asian men (ß±SE -6.2±1.2 ms, P<0.0001) and longer in Asian women (ß±SE 3.6±0.9 ms, P=0.02) compared to White men and women, respectively. Asians had greater odds of having ECG left ventricular hypertrophy (LVH) compared with Whites (odds ratio [OR] 3.56, 95% confidence interval [CI] 1.36-9.35 for men, OR 1.93, 95% CI 1.35-2.76 for women, both P<0.02). Over a mean follow-up of 11±3 years in Framingham and 8±3 years in Singapore, mortality rates were 24.5 and 13.4 per 1000 person-years among Whites and Asians, respectively. In Cox models, the presence of LVH had a greater effect on all-cause mortality in Asians compared with Whites (hazard ratio [HR] 2.66, 95% CI 1.83-3.88 vs HR 1.30, 95% CI 0.90-1.89, P for interaction=0.02). CONCLUSION: Our findings from two large community-based cohorts show prominent race differences in ECG characteristics between Whites and Asians, and also suggest a differential association with mortality. These differences may carry implications for race-specific ECG reference ranges and cardiovascular risk.

Predicting Heart Failure With Preserved and Reduced Ejection Fraction: The International Collaboration on Heart Failure Subtypes.

BACKGROUND: Heart failure (HF) is a prevalent and deadly disease, and preventive strategies focused on at-risk individuals are needed. Current HF prediction models have not examined HF subtypes. We sought to develop and validate risk prediction models for HF with preserved and reduced ejection fraction (HFpEF, HFrEF). METHODS AND RESULTS: Of 28,820 participants from 4 community-based cohorts, 982 developed incident HFpEF and 909 HFrEF during a median follow-up of 12 years. Three cohorts were combined, and a 2:1 random split was used for derivation and internal validation, with the fourth cohort as external validation. Models accounted for multiple competing risks (death, other HF subtype, and unclassified HF). The HFpEF-specific model included age, sex, systolic blood pressure, body mass index, antihypertensive treatment, and previous myocardial infarction; it had good discrimination in derivation (c-statistic 0.80; 95% confidence interval [CI], 0.78-0.82) and validation samples (internal: 0.79; 95% CI, 0.77-0.82 and external: 0.76; 95% CI: 0.71-0.80). The HFrEF-specific model additionally included smoking, left ventricular hypertrophy, left bundle branch block, and diabetes mellitus; it had good discrimination in derivation (c-statistic 0.82; 95% CI, 0.80-0.84) and validation samples (internal: 0.80; 95% CI, 0.78-0.83 and external: 0.76; 95% CI, 0.71-0.80). Age was more strongly associated with HFpEF, and male sex, left ventricular hypertrophy, bundle branch block, previous myocardial infarction, and smoking with HFrEF (P value for each comparison ≤0.02). CONCLUSIONS: We describe and validate risk prediction models for HF subtypes and show good discrimination in a large sample. Some risk factors differed between HFpEF and HFrEF, supporting the notion of pathogenetic differences among HF subtypes.

Growth differentiation factor 15 in heart failure with preserved vs. reduced ejection fraction.

AIM: Growth differentiation factor 15 (GDF15) is a cytokine highly expressed in states of inflammatory stress. We aimed to study the clinical correlates and prognostic significance of plasma GDF15 in heart failure with preserved ejection fraction (HFpEF) vs. reduced ejection fraction(HFrEF), compared with N-terminal pro-brain natriuretic peptide (NT-proBNP), an indicator of haemodynamic wall stress. METHODS: Plasma GDF15 and NT-proBNP were prospectively measured in 916 consecutive patients with HFrEF (EF <50%; n = 730) and HFpEF (EF ≥50%; n = 186), and measured again at 6 months in 488 patients. Patients were followed up for a composite outcome of death or first HF rehospitalization. RESULTS: Median GDF15baseline values were similarly elevated in HFpEF [2862 (1812 represent the 25th percentile and 4176 represent the 75th percentile) ng/L] and HFrEF [2517 (1555, 4030) ng/L] (P = 0.184), whereas NT-proBNP was significantly lower in HFpEF than HFrEF (1119 ng/L vs. 2335 ng/L, P < 0.001). Independent correlates of GDF15baseline were age, systolic blood pressure, New York Heart Association (NYHA) class, diabetes, atrial fibrillation, sodium, haemoglobin, creatinine, diuretic therapy, high sensitivity troponin T (hsTnT) and NT-proBNP (all P < 0.05). During a median follow-up of 23 months, there were 379 events (307 HFrEF, 72 HFpEF). GDF15 remained a significant independent predictor for composite outcome even after adjusting for important clinical predictors including hsTnT and NT-proBNP (adjusted hazard ratio 1.76 per 1 Ln U, 95% confidence interval 1.39-2.21; P < 0.001), regardless of HF group (Pinteraction = 0.275). GDF15baseline provided incremental prognostic value when added to clinical predictors, hsTnT and NT-proBNP (area under receiver operating characteristic curve increased from 0.720 to 0.740, P < 0.019), with a net reclassification improvement of 0.183 (P = 0.004). Patients with ≥20% GDF156months increase had higher risk for composite outcome (adjusted hazard ratio 1.68, 95% confidence interval 1.15-2.45; P = 0.007) compared with those with GDF156months within ± 20% of baseline. CONCLUSIONS: The similarly elevated levels and independent prognostic utility of GDF15 in HFrEF and HFpEF suggest that beyond haemodynamic stress (NT-proBNP), inflammatory injury (GDF15) may play an important role in both HF syndromes.

Electrocardiographic Criteria for Left Ventricular Hypertrophy in Asians Differs from Criteria Derived from Western Populations--Community-based Data from an Asian Population.

INTRODUCTION: Electrocardiographic (ECG) criteria for left ventricular hypertrophy (LVH), such as the Cornell and Sokolow-Lyon voltage criteria were derived from Western populations. However, their utility and accuracy for diagnosing echocardiographic LVH in Asian populations is unclear. The objective of this study was to assess the accuracy of ECG criteria for LVH in Asians and to determine if alternative gender-specific ECG cut-offs may improve its diagnostic accuracy. MATERIALS AND METHODS: ECG and echocardiographic assessments were performed on 668 community-dwelling Asian adults (50.9% women; 57 ± 10 years) in Singapore. The accuracy of ECG voltage criteria was compared to echocardiographic LVH criteria based on the American Society of Echocardiography guidelines, and Asian ethnicity and gender-specific partition values. RESULTS: Echocardiographic LVH was present in 93 (13.6%) adults. Cornell criteria had low sensitivity (5.5%) and high specificity (98.9%) for diagnosing LVH. Modified gender specific cut-offs (18 mm in women, 22 mm in men) improved sensitivity (8.8% to 17.5%, 0% to 14.7%, respectively) whilst preserving specificity (98.2% to 94.2%, 100% to 95.8%). Similarly, Sokolow-Lyon criteria had poor sensitivity (7.7%) and high specificity (96.1%) for diagnosing LVH. Lowering the cut-off value from 35 mm to 31 mm improved the sensitivity in women from 3.5% to 14% while preserving specificity at 94.2%. A cut-off of 36 mm was optimal in men (sensitivity of 14.7%, specificity of 95.5%). CONCLUSION: Current ECG criteria for LVH derived in Western cohorts have limited sensitivity in Asian populations. Our data suggests that ethnicity- and gender-specific ECG criteria may be needed.

Preclinical Systolic and Diastolic Dysfunctions in Metabolically Healthy and Unhealthy Obese Individuals.

BACKGROUND: Despite the substantial overlap of obesity and metabolic disease, there is heterogeneity with respect to cardiovascular risk. We sought to investigate preclinical differences in systolic and diastolic function in obesity, and specifically compare obese individuals with and without metabolic syndrome (MS). METHODS AND RESULTS: Obese individuals without cardiac disease with (OB/MS+, n=124) and without (OB/MS-, n=37) MS were compared with nonobese controls (n=29). Diastolic function was assessed by transmitral and tissue Doppler. Global longitudinal strain (LS) and time-based dyssynchrony were assessed by speckle tracking. Both OB/MS- and OB/MS+ groups had similar ejection fraction but worse systolic mechanics as assessed by LS and dyssynchrony when compared with nonobese controls. Specifically, OB/MS- had 2.5% lower LS (SE, 0.7%; P=0.001 in multivariable-adjusted analyses) and 10.8 ms greater dyssynchrony (SE, 3.3 ms; P=0.002), and OB/MS+ had 1.0% lower LS (SE, 0.3%; P<0.001) and 7.8 ms greater dyssynchrony (SE, 1.5 ms; P<0.001) when compared with controls. Obesity was associated with impaired diastolic function regardless of MS status, as evidenced by greater left atrial diameter and left ventricular mass although diastolic dysfunction was more pronounced in OB/MS+ than in OB/MS- individuals. CONCLUSIONS: Obesity is associated with subclinical differences in both systolic and diastolic function regardless of the presence or absence of MS although MS seems to be associated with worse diastolic dysfunction. When compared with controls, metabolically healthy obese had lower LS, greater dyssynchrony, and early diastolic dysfunction, supporting the notion that obesity per se may have adverse cardiovascular effects regardless of metabolic disease.

Impaired right ventricular hemodynamics indicate preclinical pulmonary hypertension in patients with metabolic syndrome.

BACKGROUND: Metabolic disease can lead to intrinsic pulmonary hypertension in experimental models. The contributions of metabolic syndrome (MetS) and obesity to pulmonary hypertension and right ventricular dysfunction in humans remain unclear. We investigated the association of MetS and obesity with right ventricular structure and function in patients without cardiovascular disease. METHODS AND RESULTS: A total of 156 patients with MetS (mean age 44 years, 71% women, mean body mass index 40 kg/m(2)), 45 similarly obese persons without MetS, and 45 nonobese controls underwent echocardiography, including pulsed wave Doppler measurement of pulmonary artery acceleration time (PAAT) and ejection time. Pulmonary artery systolic pressure was estimated from PAAT using validated equations. MetS was associated with lower tricuspid valve e' (right ventricular diastolic function parameter), shorter PAAT, shorter ejection time, and larger pulmonary artery diameter compared with controls (P<0.05 for all). Estimated pulmonary artery systolic pressure based on PAAT was 42±12 mm Hg in participants with MetS compared with 32±9 and 32±10 mm Hg in obese and nonobese controls (P for ANOVA <0.0001). After adjustment for age, sex, hypertension, diabetes, body mass index, and triglycerides, MetS remained associated with a 20-ms-shorter PAAT (ß=-20.4, SE=6.5, P=0.002 versus obese). This association persisted after accounting for left ventricular structure and function and after exclusion of participants with obstructive sleep apnea. CONCLUSIONS: MetS is associated with abnormal right ventricular and pulmonary artery hemodynamics, as shown by shorter PAAT and subclinical right ventricular diastolic dysfunction. Estimated pulmonary artery systolic pressures are higher in MetS and preclinical metabolic heart disease and raise the possibility that pulmonary hypertension contributes to the pathophysiology of metabolic heart disease.

Iron deficiency in a multi-ethnic Asian population with and without heart failure: prevalence, clinical correlates, functional significance and prognosis.

AIMS: Current heart failure (HF) guidelines highlight the importance of iron deficiency (ID) in HF. Whether HF itself or age-related comorbidities contribute to ID is uncertain, and previous data were limited to Western populations. We aimed to study the prevalence, clinical correlates, functional significance and prognosis of ID in HF patients, compared with community-based controls in a multi-ethnic Southeast Asian population. METHODS AND RESULTS: Iron status was assessed in 751 HF patients (age 62.0 ± 12.2 years, 75.5% men, 64.7% Chinese, 23.9% Malay, 10.2% Indian) and 601 controls (age 56.9 ± 10.4 years, 49.8% men, 70.9% Chinese, 21.5% Malay, 7.2% Indian). ID, defined as ferritin <100 µg/L or ferritin 100-300 µg/L and transferrin saturation (Tsat) <20%, was present in 39.3% of controls and 61.4% of HF [odds ratio (OR) 3.5, 95% confidence interval (CI) 2.5-4.9, adjusting for clinical covariates]. Independent correlates of ID in HF were Indian ethnicity (OR 2.4 vs. Chinese, 95% CI 1.2-5.0), female gender (OR 2.8, 95% CI 1.7-4.8), larger body mass index (OR 1.05/unit increase, 95% CI 1.01-1.1) and decreased left ventricular ejection fraction (OR 1.03/unit decrease, 95% CI 1.01-1.04). In a subset of 48 HF patients undergoing cardiopulmonary exercise testing, Tsat correlated with peak oxygen consumption (ρ = 0.53, P < 0.01), independent of baseline characteristics. The HF patients with Tsat <20% as well as anaemia showed the poorest event-free survival after adjusting for clinical covariates. CONCLUSIONS: ID was highly prevalent and independently related to functional capacity and outcomes in our cohort. These findings suggest a pathophysiological role of ID in HF and support its importance as a therapeutic target in Southeast Asian patients with HF.

Growth differentiation factor 15, ST2, high-sensitivity troponin T, and N-terminal pro brain natriuretic peptide in heart failure with preserved vs. reduced ejection fraction.

AIMS: Growth differentiation factor 15 (GDF15), ST2, high-sensitivity troponin T (hsTnT), and N-terminal pro brain natriuretic peptide (NT-proBNP) are biomarkers of distinct mechanisms that may contribute to the pathophysiology of heart failure (HF) [inflammation (GDF15); ventricular remodelling (ST2); myonecrosis (hsTnT); and wall stress (NT-proBNP)]. METHODS AND RESULTS: We compared circulating levels of GDF15, ST2, hsTnT, and NT-proBNP, as well as their combinations, in compensated patients with clinical HF with reduced ejection fraction (HFREF) (n = 51), HF with preserved ejection fraction (HFPEF) (n= 50), and community-based controls (n = 50). Compared with controls, patients with HFPEF and HFREF had higher median levels of GDF15 (540 pg/mL vs. 2529 and 2672 pg/mL, respectively), hsTnT (3.7 pg/mL vs. 23.7 and 35.6 pg/mL), and NT-proBNP (69 pg/mL vs. 942 and 2562 pg/mL), but not ST2 (27.6 ng/mL vs. 31.5 and 35.3 ng/mL), adjusting for clinical covariates. In receiver operating characteristic curve analyses, NT-proBNP distinguished HFREF from controls with an area under the curve (AUC) of 0.987 (P < 0.001); GDF15 distinguished HFPEF from controls with an AUC of 0.936 (P < 0.001); and the combination of NT-proBNP and GDF15 distinguished HFPEF from controls with an AUC of 0.956 (P < 0.001). NT-proBNP and hsTnT levels were higher in HFREF than in HFPEF (adjusted P < 0.04). The NT-proBNP:GDF15 ratio distinguished between HFPEF and HFREF with the largest AUC (0.709; P < 0.001). CONCLUSIONS: Our study provides comparative data on physiologically distinct circulating biomarkers in HFPEF, HFREF, and controls from the same community. These data suggest a prominent role for myocardial injury (hsTnT) with increased wall stress (NT-proBNP) in HFREF, and systemic inflammation (GDF15) in HFPEF.