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We sought to determine whether ambient air pollution is associated with interstitial lung abnormalities (ILA) and high attenuation areas (HAA), which are qualitative and quantitative measurements of subclinical ILD on computed tomography. We performed analyses of 6813 community-based dwellers enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA), a U.S.-based prospective cohort study. We used cohort-specific spatiotemporal models to estimate predictions of ambient pollution (PM2.5, NOx, NO2 and O3) at each home. Participants underwent serial assessment of HAA by cardiac CT-scan and a subset of participants was assessed for ILA using full lung CT scan at 10 year follow-up. We used multivariable logistic regression and linear mixed models adjusted for age, sex, ethnicity, education, tobacco use, scanner technology and study site. The odds of ILA increased 1.62-fold per 40ppb increment in NOx (95%CI 0.97 to 2.71, p-value 0.06), and were strongest in non-smokers (2.60-fold increase per 40ppb increment in NOx, 95% CI 1.20 to 5.61, p-value 0.02). HAA increased by 0.54% per year per 5μg/m3 increment in PM2.5 (95%CI 0.02% to 1.10%, p-value 0.04) and by 0.55% per year per 40ppb increment in NOx (95%CI 0.08% to 1.00%, p-value 0.02). Ambient air pollutants were associated with measurements of subclinical ILD.

Rationale: Intense exercise in elite athletes is associated with increased left ventricular (LV) and right ventricular (RV) mass and volumes. However, the effect of physical activity on the RV in an older community-based population is unknown. Objectives: We studied the association between levels of physical activity in adults and RV mass and volumes. Methods: The Multi-Ethnic Study of Atherosclerosis (MESA) performed cardiac magnetic resonance imaging on community-based participants without clinical cardiovascular disease. RV volumes were determined from manually contoured endocardial margins. RV mass was determined from the difference between epicardial and endocardial volumes multiplied by the specific gravity of myocardium. Metabolic equivalent-minutes/day were calculated from the selfreported frequency, duration, and intensity of physical activity. Measurements and Main Results: The study sample (n 5 1,867) was aged 61.8 6 10 years, 48% male, 44% white, 27% African American, 20% Hispanic, and 9% Chinese. Higher levels of moderate and vigorous physical activity were linearly associated with higher RV mass (P 5 0.02) after adjusting for demographics, anthropometrics, smoking, cholesterol, diabetes mellitus, hypertension, and LV mass. Higher levels of intentional exercise (physical activity done for the sole purpose of conditioning or fitness) were nonlinearly associated with RV mass independent of LV mass (P 5 0.03). There were similar associations between higher levels of physical activity and larger RV volumes. Conclusions: Higher levels of physical activity in adults were associated with greater RV mass independent of the associations with LV mass; similar results were found for RV volumes. Exercise-associated RV remodeling may have important clinical implications.Keywords: exercise; pulmonary heart disease; pulmonary hypertension; magnetic resonance imaging Physical activity has many physiologic effects on the cardiovascular system, both acutely and chronically. Exercise acutely raises cardiac output through tachycardia, augmented stroke volume, and increased ejection fraction (1). Systemic and pulmonary arterial pressures increase and vascular resistances decrease. Long-term high-intensity physical activity is associated with increased left ventricle (LV) mass, volume, and wall thickness (2-6), a constellation of changes known as the ''athlete's heart.'' Most studies of the cardiac effects of physical activity focus on LV morphology in small cohorts of young male endurance athletes.The substantial differences in embryology, morphology, perfusion, workload, and downstream vascular beds (and the diseases which affect them) make extrapolation of findings from the LV to the right ventricle (RV) difficult. The small number of studies performed have shown significant effects of intense exercise on RV mass and volumes (3-6). However, because RV structure and function are difficult to measure with standard transthoracic echocardiography, little is known about the relationship between physical activity and RV str...

Introduction Pulmonary insufficiency (PI) is associated with right ventricular (RV) dilation, dysfunction and exercise intolerance in patients with tetralogy of Fallot (TOF). We sought to compare RV function and exercise performance in patients with valvar pulmonary stenosis (VPS) following pulmonary balloon valvuloplasty to those with repaired TOF with similar degrees of PI. Methods We performed a cross-sectional study of patients with VPS and TOF. Cardiac magnetic resonance (CMR) and exercise stress test (EST) were performed. Subjects were matched by time from initial procedure and severity of PI using propensity scores. Results After matching, there were 16 patients with VPS and 16 with TOF for comparison, with similar demographics. Time from initial procedure was 14 years (12; 16), p= 0.92, and pulmonary regurgitant fraction was 19 % (6; 31), p= 0.94, Patients with TOF had lower ejection fraction [58 % (53; 66) vs. 65 % [60; 69], p= 0.04] and more RV hypertrophy [69 g/m2 [52; 86] vs. 44 g/m2 [32; 66], p=0.04] compared to those with VPS. Aerobic capacity was worse in patients with TOF [68 ± 19% mVO2 (56; 84) vs. 82 ± 9.2 % (74; 89) in VPS, p=0.01], with a trend for less habitual physical activity [0.9 (0; 12) vs. 8 hours/ week (4; 12), p= 0.056], respectively. Conclusions With similar degrees of PI, patients with TOF demonstrate worse RV function and aerobic capacity as compared to patients with just VPS. Habitual exercise may in part explain differences in exercise performance and should be further explored.