Effect of Obesity on Electrocardiographic Left Ventricular Hypertrophy in Hypertensive Patients

Abstract

Abstract-Obesity 3,4 has been associated with increased morbidity and mortality. However, low sensitivity of standard voltage criteria for detection of LV hypertrophy (LVH) has limited utility of the ECG for identification of patients with LVH. [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] Although Cornell voltage criteria modestly improve ECG detection of LVH in hypertensive patients, 6,7 the product of Cornell voltage and QRS duration (Cornell voltage-duration product), 8,9 an approximation of the area under the QRS, 10 appears to further enhance sensitivity of the ECG for LVH while maintaining high specificity. As a consequence, Cornell voltage-duration product criteria were used in combination with SokolowLyon voltage 5 to identify hypertensive patients at increased risk of subsequent cardiovascular morbidity and mortality for inclusion in the Losartan Intervention For Endpoint (LIFE) Reduction in Hypertension Study, a prospective trial designed to compare the efficacy of losartan and atenolol in reducing the risk of cardiovascular events. 21,22 Obesity has been associated with increases in LV wall thickness, LV mass, and the prevalence of echocardiographic LVH, independent of the impact of blood pressure. [23][24][25][26] Conversely, obesity has been shown to decrease sensitivity of precordial lead ECG criteria for LVH, presumably because of the attenuating effects of increased distance of exploring electrodes from the LV and attenuation of QRS amplitudes by interposed tissue. 11,14 -20 However, obesity is common in hypertensive patients, [23][24][25][26] raising questions regarding the utility of precordial voltage criteria in detecting hypertensive LVH. Moreover, previous studies of the impact of increased

The electrocardiogram is an unreliable method of identifying left ventricular hypertrophy in stable, treated angina patients

“…In addition, the LIFE investigators also showed that obese patients tended to have lower Sokolow-Lyon voltages than non-obese patients but had higher Cornell product. 20 The importance of detecting LVH in CAD patients is based on several reasons. Firstly, three previous studies in CAD patients have demonstrated that the relative risk of cardiac death conferred by LVH was 2.14, 2.4 and 2.1 after adjustment for other factors including hypertension and the number of coronary vessels affected.…”

The epidemiology of left ventricular hypertrophy in type 2 diabetes mellitus

“…Obesity and insulin resistance have been implicated in the pathogenesis of non-hypertensive LVH. Obesity has been demonstrated to be an independent predictor of left ventricular chamber size, left ventricular wall thickness and left ventricular mass [31,32]. Insulin has been demonstrated to have trophic effects on cardiomyocytes in cell culture and may act as a growth factor, promoting the development of LVH [33].…”

Adverse effects of left ventricular hypertrophy in the reduction of endpoints in NIDDM with the angiotensin II antagonist losartan (RENAAL) study

“…ECGs were then assessed centrally, using the Cornell product and Sokolow-Lyon voltage criteria, which had been used in the LIFE (Losartan Intervention for Endpoint Reduction in Hypertension) study and validated [17][18][19][20][21] in a large number of patients. Furthermore, the Cornell product criteria have been shown to be more sensitive in diagnosing LVH in obese patients and were thus considered to be more robust in assessing the presence or absence of LVH in this study [22].…”