Relationship of Body Mass Index with Changes in Cardiac Geometry and Function in 5,898 Patients Evaluated by Transthoracic Echocardiography

Introduction: This study describes the relationship between Body Mass Index (BMI) and the cardiac geometry and heart function assessed by transthoracic echocardiography. Materials and methods: We analyzed 5,898 echocardiographic studies in an age range between 18.0 and 98.6 years. Results: The BMI ranged from 15.23 to 49.61 kg/m2. The increased BMI had a statistically significant direct association with left ventricular mass initially observing a light concentric hypertrophy, which becomes eccentric as it increases, especially when allometric ratio is normalized (Height2.7). An increase in ejection volume and cardiac output was observed, as well as an inverse association between body mass index and the E/A ratio of mitral filling, with a significant reduction of e’ velocity of tissue Doppler, showing a relaxation-type diastolic dysfunction in overweight or obese individuals. We observed a slight yet significant increase in the left atrial area and volume indexed to body mass. There were no differences in the right ventricular geometry and function. Conclusions: The present study demonstrated a significant direct association between the increase in BMI and LV myocardial mass. Indexing LV mass to height 2.7 avoids artifacts related to body mass index, especially in subjects with grade II and III obesity. (Arq Bras Cardiol: Imagem cardiovasc. 2015; 28(1):3-16)