Evaluation of cardiac functions and atrial electromechanical delay in children with adenotonsillar hypertrophy.

Deterioration of the right ventricular (RV) functions and the increase in the pulmonary arterial pressure (PAP) of children with moderate to severe adenotonsillar hypertrophy (ATH) have been well described. In addition to these complications, this study aimed to investigate the influence of ATH on the conduction system. The study investigated 46 patients with a diagnosis of ATH and 46 healthy control subjects. Conventional echocardiography, P-wave dispersion (Pd), tissue Doppler imaging (TDI) findings, and atrial electromechanical delay (AED) were compared between the patients and the control subjects before and after adenotonsillectomy. The maximum P-wave duration and Pd were significantly higher in the patients than in the control subjects (p < 0.001). The patient group showed significantly greater RV end-diastolic dimension (p = 0.01), right atrial area (p < 0.001), and mean PAP (p = 0.03) but lower E/A ratios for the mitral (p = 0.04) and tricuspid (p = 0.01) valves and a shorter pulmonary flow trace acceleration time (p = 0.03). The tricuspid annular-plane systolic excursion was similar between these groups (p = 0.21). In the patient group, TDI studies showed significantly lower E'/A' ratios for the tricuspid lateral (p = 0.006) and mitral septal (p = 0.003) segments than in the control group. The myocardial performance index was lower for the mitral lateral, mitral septal, and tricuspid lateral segments in patient group (p < 0.001). Similarly, AED was prolonged in the patient group at all three segments (p < 0.001). Also, the patient group showed a significantly longer interatrial (p = 0.03) and intraatrial (p = 0.04) electromechanical delay. However, all the electro- and echocardiographic parameters were similar between the patients and the control subjects after adenotonsillectomy (p > 0.05). The prolongations in P-wave duration, Pd, and inter- and intraatrial electromechanical delays were first shown in this population. The cardiac changes induced by ATH-associated hypoxia may facilitate arrhythmias during the long term.