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Dietary intake of n-3 polyunsaturated fatty acids is associated with a lower incidence of cardiovascular events. Mechanisms underlying this association are poorly understood but may include beneficial effects on physical conditioning and vagal tone. We investigated the association of n-3 fatty acid levels to exercise parameters in 992 subjects with stable coronary artery disease. Cross-sectional associations of heart rate recovery time, treadmill exercise capacity, and exercise time with docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels were evaluated in multivariable linear and logistic regression models adjusted for demographics, cardiovascular risk factors, co-morbidities, self-reported physical activity, medication use, and left ventricular function. After multivariable adjustment, n-3 fatty acid levels (DHA + EPA) were strongly associated with heart rate recovery (beta 2.1, p = 0.003), exercise capacity (beta 0.8, p <0.0001), and exercise time (beta 0.9, p <0.0001). Increasing levels of (DHA + EPA) were also associated with decreased risk of impaired heart rate recovery (odds ratio 0.8, p = 0.004) and exercise time (odds ratio 0.7, p = 0.01) and trended toward significance for exercise capacity (odds ratio 0.8, p = 0.07). These associations were not modified by demographics, body mass index, smoking, co-morbid conditions, statin use, or β-blocker use (p for interaction >0.1 for all comparisons). In conclusion, an independent association exists between n-3 fatty acid levels and important exercise parameters in patients with stable coronary artery disease. These findings support the hypothesis that n-3 fatty acids may increase vagal tone and physical conditioning. [ABSTRACT FROM AUTHOR]

Heart failure (HF) is a common public health problem, and many new cases are now recognized to occur in patients with preserved left ventricular ejection fraction. β Blockers improve the outcomes of patients with known left ventricular systolic dysfunction, but whether β blockers provide similar protection among patients with left ventricular diastolic dysfunction is unclear. We studied the association between use of β blockers and subsequent hospitalization for HF in patients with diastolic dysfunction and stable coronary heart disease. We evaluated medication use and performed echocardiography at baseline in a prospective cohort of 911 outpatients with known coronary heart disease from the Heart and Soul Study. Hospitalizations for HF were assessed by blinded review of the medical records during an average follow-up of 5.2 years. Of the 911 participants, 118 (13%) had diastolic dysfunction, of whom 2 were lost to follow-up. Of the 116 remaining patients, 19 (25%) of the 77 using β blockers were hospitalized for HF compared to 16 (41%) of the 39 not using β blockers (age-adjusted hazard ratio 0.51, 95% confidence interval 0.26 to 1.00; p = 0.05). This association remained after additional adjustment for gender, smoking, history of myocardial infarction, diabetes, and creatinine (hazard ratio 0.46, 95% confidence interval 0.23 to 0.93; p = 0.03). The results were similar after excluding 31 participants with a history of self-reported HF (hazard ratio 0.33, 95% confidence interval 0.13 to 0.86; p = 0.02) and 24 participants with concurrent systolic dysfunction (hazard ratio 0.36, 95% confidence interval 0.14 to 0.89; p = 0.03). In conclusion, the use of β blockers is associated with a decreased risk of hospitalization for HF in patients with diastolic dysfunction and stable coronary heart disease. [Copyright &y& Elsevier]

Obesity is an independent risk factor for recurrent events among patients with established coronary heart disease (CHD). The goal of the present study was to identify potential mechanisms underlying this association. We measured the waist-to-hip ratio and body mass index in 979 outpatients with stable CHD and followed them for a mean of 4.9 years. We used proportional hazards models to evaluate the extent to which the association of obesity with subsequent heart failure (HF) hospitalization or cardiovascular (CV) events (myocardial infarction, stroke, or CHD death) was explained by baseline co-morbidities, cardiac disease severity, inflammation, insulin resistance, neurohormones and adipokines. Of the 979 participants, 128 (13%) were hospitalized for HF and 152 (16%) developed a CV event. Each standard deviation (SD) increase in the waist-to-hip ratio was associated with a 30% increased risk of HF hospitalization (unadjusted hazard ratio [HR] 1.3, 95% confidence interval [CI] 1.1 to 1.6). This association was not attenuated after adjustment for potential mediators (HR 1.6, 95% CI 1.2 to 2.1). Likewise, each SD increase in the waist-to-hip ratio was associated with a 20% greater risk of CV events (unadjusted HR 1.2, 95% CI 1.0 to 1.4), and this remained unchanged after adjustment for potential mediators (adjusted HR 1.3, 95% CI 1.0 to 1.5). The body mass index was not associated with the risk of HF or CV events. In conclusion, abdominal obesity is an independent predictor of HF hospitalization and recurrent CV events in patients with stable CHD. This association does not appear to be mediated by co-morbid conditions, cardiac disease severity, insulin resistance, inflammation, neurohormones, or adipokines. [Copyright &y& Elsevier]

Pulmonary vascular resistance (PVR) is an important hemodynamic variable that affects prognosis and therapy in a wide range of cardiovascular and pulmonary conditions. We sought to determine whether a noninvasive estimate of PVR predicts adverse outcomes in patients with stable coronary artery disease. Using Doppler echocardiography we measured the estimated PVR (defined as the ratio of the tricuspid regurgitant velocity [TRV] to the velocity–time integral [VTI] of the right ventricular outflow tract [RVOT]) in 795 ambulatory patients with stable coronary artery disease. Participants were categorized by quartiles of the TRV/VTIRVOT ratio. Hazard ratios (HRs) and 95% confidence intervals were calculated for all-cause mortality, heart failure hospitalization, and adverse cardiovascular events (cardiovascular death, nonfatal myocardial infarction, or stroke). After 4.3 years of follow-up there were 161 deaths, 44 deaths from cardiovascular causes, 103 heart failure hospitalizations, and 120 adverse cardiovascular events. Compared with patients in the lowest TRV/VTIRVOT quartile, those in the highest quartile were at increased risk of all-cause mortality (unadjusted HR 1.8, 95% confidence interval 1.3 to 2.5), heart failure hospitalization (unadjusted HR 2.9, 95% confidence interval 2.0 to 4.3), and adverse cardiovascular events (unadjusted HR 2.0, 95% confidence interval 1.4 to 2.9). After multivariate adjustment, patients in the highest quartile were at increased risk of heart failure hospitalizations (adjusted HR 2.5, 95% confidence interval 1.3 to 4.7). In conclusion, a noninvasive estimate of PVR (TRV/VTIRVOT ratio) predicts mortality, heart failure hospitalization, and adverse cardiovascular events in patients with stable coronary artery disease. [Copyright &y& Elsevier]

The hyperdynamic circulation associated with cirrhosis is typically characterized by high cardiac output and low systemic and pulmonary vascular resistance (PVR). Approximately 4% of cirrhotic patients develop portopulmonary hypertension, which is an important predictor of hemodynamic instability after orthotopic liver transplantation. Doppler estimation of pulmonary artery systolic pressure (PASP) is used as a screening test for the presence of portopulmonary hypertension. We tested the accuracy of a noninvasive measurement of PVR (ratio of peak tricuspid regurgitant velocity [TRV] to right ventricular outflow tract velocity time integral [VTIRVOT]) to detect increased PVR in a population before liver transplantation. We compared test characteristics of the TRV/VTIRVOT ratio to echocardiographically derived PASP for detection of invasively measured PVR >1.5 Wood units. There was no significant correlation between Doppler-derived PASP and invasively measured PVR. There was a moderate and significant correlation between TRV/VTIRVOT ratio and invasively measured PVR. Compared with Doppler-derived PASP, the TRV/VTIRVOT ratio was a more accurate test for PVR >1.5 Wood units. Using a cut-off value of TRV/VTIRVOT >0.12, the sensitivity and negative predictive value for PVR >1.5 Wood units were 100%. In conclusion, the TRV/VTIRVOT ratio is a more accurate screening test for the presence of portopulmonary hypertension than PASP in patients undergoing orthotopic liver transplantation. Routine use of this ratio may decrease the need for invasive hemodynamic assessment in this patient population. [Copyright &y& Elsevier]

Hypertrophic cardiomyopathy (HC) is the most common genetic heart disease and an important cause of sudden death and heart failure symptoms. The current prevalence for HC (1:500) is based on echocardiographic population studies in which a substantial proportion of affected subjects have not come to clinical recognition. Therefore, we sought to define the subset of patients with HC who are diagnosed in the US. A proprietary integrated claims database including medical condition International Classification of Diseases, Ninth Revision diagnostic codes for over 160 million individual patients in the US was interrogated for 2013 to identify the prevalence of clinically recognized HC. Patients with ≥1 claim for any of the HC International Classification of Diseases, Ninth Revision diagnosis codes from January to December 2013 were identified. The combined occurrence rate of HC was stratified by age and gender and multiplied by the 2013 United States population in the same age/gender categories to produce the final projected prevalence. The analysis was performed on 169,089,614 patients, of whom 59,009 unique patients were identified with ≥1 claim for HC. The projected estimated occurrence of diagnosed HC in the US in 2013 was 1:3,195 for a total of 98,958 subjects. Average age at HC diagnosis was in the fifth decade of life, with 43% of the cohort composed of women. In conclusion, leveraging a claims-based data analytic technique, about 100,000 patients are diagnosed clinically with HC in the US, an occurrence which is less than the prevalence reported in systematic population studies based on echocardiographic diagnosis. This observation supports the view that many patients with HC are undiagnosed throughout life and enhances our understanding of the burden of this genetic heart disease on the health care system. [ABSTRACT FROM AUTHOR]