Abstract 4991: Left Ventricular Remodeling is Associated with Physical Activity in a Community-Based Population: The Multi-Ethnic Study of Atherosclerosis (MESA)
Physiologic myocardial remodeling occurs in individuals who undergo high level athletic training. We evaluated the relationship between physical activity (PA) and left ventricular (LV) size and function in a community-based sample. 4992 MESA participants (age 45– 84 years; 52% female) free of clinical cardiovascular disease (CVD) underwent cardiac MRI and answered a standard semi quantitative questionnaire for assessment of typical PA patterns in the prior month. Intentional exercise and total moderate and vigorous physical activity (MVPA) levels were evaluated as metabolic equivalent minutes per day (MET/min/day). Associations of body surface area indexed LV mass and volumes with exercise and MVPA were estimated using multivariable regression models adjusted for gender, age, race, blood pressure, diabetes, lipid levels and smoking. End diastolic LV mass and volume were positively associated with exercise and MVPA (p<0.001) in a non-linear fashion with associations becoming weaker at higher levels of exercise and MVPA (Figure⇓). Because both LV mass and volume increased proportionally, the LV mass/volume ratio showed no association with exercise or MVPA. Stroke volume was positively associated with exercise and MVPA (p<0.001) (Figure⇓). Cardiac output and ejection fraction showed no statistically significant association with exercise or MVPA, while resting heart rate was inversely associated (p < 0.001). In a CVD free population, MVPA and exercise were associated with LV remodeling defined by larger LV mass and end diastolic volume, with decreased resting heart rate.