The importance of a shared definition of left ventricular hypertrophy: The case of obese women

Background Left ventricular hypertrophy (LVH) is a risk factor for all-cause mortality. Left ventricular (LV) mass is usually indexed for normalizing the value to the patients phenotype and a correction by body surface area (BSA) is widely utilized being the only approved one according to the last echocardiography guidelines. However indexing LV mass by BSA may cause an underestimation of LVH prevalence in obese subjects and many authors have utilized in the obese subset of patients a correction by height^2.7. The aim of our study was to quantify the number of obese patients who, despite having an increased LV mass, fall in the range of normality because they do not reach the LVH cutoff according to the new guidelines. Methods We reviewed the echocardiograms of 384 white women free from cardiovascular disease. Ninety-six patients (25%) were obese: among them 42 had mild obesity and 54 had moderate or severe obesity. Results In the obese group, the prevalence of LVH using the absolute LV mass value was similar to the one obtained with the height^2.7 correction while a significant smaller number of patients had LVH according to BSA correction. Our study confirms that the method used for correcting LV mass significantly influences the diagnosis of LVH in a non-selected female population: using body surface area underestimates the prevalence of LVH as compared to allometric measures in the obese subset of patients. Conclusion We recommend that height2.7 be used for LV mass correction in obese patients.