Background: Obesity in childhood is strongly associated with elevated arterial blood pressure and risk of hypertension. The aim of the study was the evaluation of left ventricular (LV) function in hypertensive and white coat hypertensive overweight children and teenagers.

Methods: The study group consisted of 74 overweight patients aged 10.3 ± 3.1 years (range: 6–16 years) diagnosed as hypertensive in standard blood pressure measurement. The control group consisted of 31 normotensive and normoweight children. Ambulatory blood pressure monitoring (ABPM) and echocardiographic assessment of the LV mass and function were performed in all participants.

Results: Using ABPM hypertension was confirmed in 20 (27%) children. In the 54 (73%) remaining children white coat hypertension was diagnosed. The analysis of echocardiographic parameters revealed higher LV mass index (LVMI) in hypertensive overweight than in normotensive normoweight children (47.5 ± 9.2 g/m2.7 vs. 39.8 ± 12.1 g/m2.7; p < 0.05) and no difference between overweight hypertensive and white coat hypertension-hypertensive groups. The deceleration time of mitral early filling (DCT) was longer in hypertensive normoweight children than in normotensive overweight patients (219.5 ± 110.3 ms vs. 197.8 ± 65.8 ms; p < 0.05). A significant correlation between systolic blood pressure load (SBPL) and DCT (r = 0.57) and moderate correlation between SBPL and LVMI (r: 0.48) as well as between LVMI and isovolumetric relaxation time (r = 0.37) were found.

Conclusions: In overweight children the diagnosis of hypertension should be confirmed in ABPM because of the high prevalence of white coat hypertension. Periodic echocardiographic examinations should be recommended in overweight children with increased SBPL and decreased systolic nocturnal deep because of the possibility of LV function impairment.