Determinants and Improvement of Electrocardiographic Diagnosis of Left Ventricular Hypertrophy in a Black African Population Ahmadou M. Jingi 1 , Jean Jacques N. Noubiap 2 *, Philippe Kamdem 3 , Samuel Kingue 1,4 1 Department of Internal Medicine and Specialties, Faculty of Medicine and Biomedical Sciences, University of Yaounde ´ I, Yaounde ´, Cameroon, 2 Internal Medicine Unit, Ede ´a Regional Hospital, Ede ´a, Cameroon, 3 Centre Me ´dical de la Trinite ´ , Bafoussam, Cameroon, 4 Department of Internal Medicine, Yaounde ´ General Hospital, Yaounde ´, Cameroon Abstract Background: Left ventricular hypertrophy (LVH) is a major cardiovascular risk factor. The electrocardiogram (ECG) has been shown to be a poor tool in detecting LVH due to cardiac and extracardiac factors. We studied the determinants and possibility of improving the test performance of the ECG in a group of Black Africans. Methods: We studied echocardiograms and electrocardiograms of 182 Cameroonian patients among whom 113 (62.1%) were having an echocardiographic LVH. Echocardiographic LVH was defined as Left Ventricular Mass Indexed to height 2.7 (LVMI).48 g/m 2.7 in men, and .44 g/m 2.7 in women or Body Surface Area $116 g/m 2 in men, and $96 g/m 2 in women. Test performances were calculated for 6 classic ECG criteria Sokolow-Lyon, Cornell, Cornell product, Gubner-Ungerleiger, amplitudes of R in aVL, V 5 and V 6 . Results: The most sensitive criteria were Cornell (37.2%) and Sokolow-Lyon index (26.5%). The most specific criteria were Gubner (98.6%), RaVL (97.1%), RV 5 /V 6 (95.7%) and Cornell product (94.2%). The performance of the ECG in diagnosing LVH significantly increased with the severity of LVH for Cornell index (r = 0.420, p,0.0001) and Sokolow index (r = 0.212, p = 0.002). It decreased with body habitus (r = 20.248, p = 0.001) for Sokolow-Lyon index. Cornell index was less affected (age p = 0.766; body habitus: p = 0.209). After sex-specific adjustment for BMI, Cornell BMI sensitivity increased from 37.2% to 69% (r = 0.472, p,0.0001), and Sokolow-Lyon BMI sensitivity increased from 26.5% to 58.4% (r = 0.270, p,0.001). Conclusion: The test performance of the ECG in diagnosing LVH is low in this Black African population, due to extracardiac factors such as age, sex, body habitus, and cardiac factors such as LVH severity and geometry. However, this performance is improved after adjustment for extracardiac factors. Citation: Jingi AM, Noubiap JJN, Kamdem P, Kingue S (2014) Determinants and Improvement of Electrocardiographic Diagnosis of Left Ventricular Hypertrophy in a Black African Population. PLoS ONE 9(5): e96783. doi:10.1371/journal.pone.0096783 Editor: Larisa G. Tereshchenko, Johns Hopkins University SOM, United States of America Received November 18, 2013; Accepted April 11, 2014; Published May 8, 2014 Copyright: ß 2014 Jingi et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: The authors have no support or funding to report. Competing Interests: The authors have declared that no competing interests exist. * E-mail: noubiapjj@yahoo.fr Introduction Increased left ventricular mass (LVM) is an adaptation of the heart to increased hemodynamic burden, and alters cardiac functioning. It is often associated with hypertension and has been shown to be an independent cardiovascular risk factor [1]. Methods of diagnosing left ventricular hypertrophy (LVH) with increasing performance include a comprehensive clinical assess- ment, chest X-ray, electrocardiography (ECG), Cardiac ultra- sound, CT scan, Nuclear Magnetic Resonance imaging (NMR). The ECG is the most cost-effective and is recommended for routine use in assessing LVH [2,3]. The test performance of the ECG has been shown to be influenced by race, gender, age and body habitus [4,5]. Adjustment of ECG LVH criteria for body mass index (BMI) and age has been shown to improve the classification accuracy in Caucasians [6]. Such studies are scarce in Sub-Saharan Africa and mostly looked at the test performance of the ECG [7,8]. Our objective was to study the test performance and determinants of some classic easy to use ECG criteria and the possibility of improvement. Methods Ethical Considerations The study was granted ethical approval by the Institutional Review Board of the Health Science Foundation, Cameroon, and was performed in accordance with the guidelines of the Helsinki Declaration. Written informed consent was obtained from all the participants. Study Design and Setting The study was conducted between April and December 2011 in the ‘‘Centre Medical de la Trinite ´’’, one of the two cardiologic clinics in the West Region of Cameroon. PLOS ONE | www.plosone.org 1 May 2014 | Volume 9 | Issue 5 | e96783