Blood pressure parameters affecting ventricular repolarization in obese children

Ventricular repolarization (VR) increases the risk of sudden cardiac death due to ventricular arrhythmia. We aimed to evaluate the blood pressure (BP) parameters affecting VR in obese children.

Obese (BMI ≥ 95p) and healthy children ≥ 120 cm between January 2017 and June 2019 were included. Demographic and laboratory data, peripheral and central BPs evaluated by a device capable of ambulatory blood pressure monitoring (ABPM), and pulse wave analysis were assessed. Electrocardiographic ventricular repolarization indices, left ventricular mass index (LVMI), and relative wall thickness (RWT) were calculated.

A total of 52 obese and 41 control patients were included. Uric acid, triglyceride, total cholesterol, LDL, and ALT values, systolic and diastolic office BPs, 24-h, daytime and nighttime systolic and mean arterial BPs, daytime diastolic BP SDS levels, daytime and nighttime systolic loads, daytime diastolic load, 24-h, daytime and nighttime central systolic and diastolic BPs, and pulse wave velocity values were significantly higher, whereas 24-h, daytime and nighttime AIx@75 were similar between the groups. fT4 levels of obese cases were significantly lower. QTcd and Tp-ed were higher in obese patients. Although RWT was higher in obese cases, LVMI values and cardiac geometry classifications were similar. The independent factors affecting VR in obese cases were younger age and higher diastolic load at night (B =  - 2.83, p = 0.010; B = 0.257, p = 0.007, respectively).

Obese patients have higher peripheral and central BP, arterial stiffness, and higher VR indices that develop before an increase in LVMI. It would be useful to prevent obesity from an early age and follow up nighttime diastolic load to control VR associated sudden cardiac death in obese children. A higher resolution version of the Graphical abstract is available as Supplementary information.