IJCS | Volume 32, Nº5, September/October 2019

515 stage B HF, which can significantly change prognosis and treatment. Thus, vitamin D status measurement is a useful tool for classifying patients at increased risk of diastolic dysfunction inprimaryhealthcare. Nutritional assessment of VitaminD status allows for risk stratification of patients from the very beginning of healthcare assistance. The echocardiographic evaluation performed after patient screening and selection can provide an early and accurate diagnosis in the initial stages of heart failure (A and B). Limitations This was a cross-sectional observational study, which did not enable the establishment of cause and effect relationships, because coexistence in clinical settings can hinder this evaluation, whichmay be concluded through longitudinal analysis. The study sought to assess a representative sample of the general population. However, we could not completely exclude the selection bias, due to the higher demand for health services by female patients. Echocardiographic tests were performed using two portable equipment from distinct manufacturers, which did not permit storage on backup devices, so that we would be able to calculate the intra- and inter-examiner coefficient of variation. The equipment did not have advanced techniques for cardiac deformation imaging, and the evaluation is restricted to the tissue technique, which may underestimate the involvement of systolic function assessment in the sample. Author contributions Conception and design of the research: Macedo EA. Analysis and interpretation of the data: Jorge AJL, Leite AR. Statistical analysis: Rosa MLG. Writing of the manuscript: Santos LHS. Critical revision of the manuscript for intellectual content: Vieira JS. Potential Conflicts of Interest The authors have no relevant conflict of interests to disclose. Sources of funding The study was financed by the authors. Laboratory tests were donated by Sergio Franco Laboratories and Abbott Laboratory (BNP). Echocardiography and electrocardiography tests were conducted by researchers of the DIGITALIS Study. Study Association This manuscript is part of the Master’s dissertation of Erica de Abreu Macedo from Universidade Federal Fluminense . Ethics approval and consent to participate This study was approved by the Ethics Committee of the Universidade Federal Fluminense under the protocol number 0077.0.258.000-10. All the procedures in this study were in accordance with the 1975 Helsinki Declaration, updated in 2013. Informed consent was obtained from all participants included in the study. 1. Feigenbaum H, Amstrong WF, Ryan T. Ecocardiografia. 6a ed. Rio de Janeiro: Guanabara Koogan; 2007. 2. Kircher B, Abbott JA, Pau S, Gould RG, Himelman RB, Higgins CB, et al. Left atrial volume determination by biplane two-dimensional echocardiography: validation by cine computed tomography. AmHeart J. 1991;121(3 t 1):864-71. 3. OH JK, Seward JB, Tajik AJ. The echo manual. 3rd ed. Philadelphia: Lippincott Williams & Wikilkins; 2006. 4. Mesquita ET, Jorge AJL. ICFEN – Insuficiência cardíaca com fração de ejeção normal. São Paulo: Ed. Atheneu; 2009. 5. Montera VSP, Mesquita ET. O The role of vitamin D in heart failure. Rev Bras Cardiol. 2010;23(2):124-30. 6. ZIttermann, A. Vitamin D status, supplementation and cardiovascular disease. Anticancer Res. 2018;38(2):1179-86. 7. Jorge AJL, Cordeiro JR, Rosa MLG, Bianchi, DBC. Vitamin D deficiency and cardiovascular diseases. Int J Cardiovasc. Sci. 2018;31(4):422-32. 8. WithamD, Crighton LJ, Gillespie ND, Struthers AD, McMurdoME. The effects of vitamin D supplementation on physical function and quality of life in older patients with heart failure: a randomized controlled trial. Circ Heart Fail. 2010;3(2):195-201. 9. Rendina D, De Fillippo G, Strazzulo P. Should vitamin D status be assessed in patients with congestive heart failure?NutrMetab Cardiovasc Dis. 2010;20(9):627-32. 10. Pilz S, Tomaschitz A, Drechsler C, Dekker JM, März W. Vitamin D deficiency and myocardial diseases. Mol Nutr Food Res. 2010;54(8):1103-13. 11. Jorge AJL, Rosa ML, Fernandes LCM, Freire MC, Rodrigues RC, Correia DMS, et al. Heart Failure Prevalence Study among Patients Enrolled in References Macedo et al. Increased left atrial volume Int J Cardiovasc Sci. 2019;32(5):508-516 Original Article