Left ventricular hypertrophy and QT interval in obesity and in hypertension: effects of weight loss and of normalisation of blood pressure

BACKGROUND: Left ventricular hypertrophy (LVH) and prolonged QT interval at ECG (QTc) are common in both obesity and arterial hypertension (AH), and are risk factors for cardiovascular disease and sudden death. METHODS: We compared the frequencies of LVH (ECG criteria) and QTc in obese-AH (n ¼ 41), in normotensive obese (n ¼ 75), in lean-AH (n ¼ 30), and in lean controls (n ¼ 68) comparable for age and sex; in obese patients, LVH and QTc were evaluated under basal conditions and 1 y later, that is, after a significant weight loss induced by bariatric surgery. RESULTS: LVH was more frequent, and QTc was longer, in obese-AH, in normotensive obese, and in lean-AH than in lean controls; after weight loss, frequency of LVH decreased in obese subjects becoming normotensive (n ¼ 87), not in obese subjects remaining hypertensive (n ¼ 29), while QTc decreased in all obese subjects. CONCLUSION: Weight loss can effectively reduce QTc; when concomitant AH disappears, weight loss can also reduce the prevalence of LVH. In obese patients remaining hypertensive, aggressive pharmacological treatment is therefore indicated to correct LVH.