Pulmonary hypertension evaluation by Doppler echocardiogram in children and adolescents with mouth breathing syndrome.

INTRODUCTION: Adenotonsillar hyperplasia (ATH) and allergic rhinitis (AR) are the most common causes of upper airway obstruction in children. Such diseases, by affecting the upper airways, can cause chronic alveolar hypoventilation, pulmonary vasoconstriction and pulmonary hypertension, which in some cases, are irreversible.

OBJECTIVE: This cross-sectional study aimed to evaluate the prevalence of pulmonary hypertension in two groups of mouth-breathing (MB) 2-12 years old children with ATH and isolated allergic rhinitis, through Doppler echocardiography.

METHODS: 54 patients with ATH and indications for adenoidectomy and/or tonsillectomy and 24 patients with persistent allergic rhinitis were selected and submitted to Doppler echocardiography. The Systolic Pulmonary Artery Pressure (SPAP) was determined by tricuspid regurgitation and the Mean Pulmonary Artery Pressure (MPAP) was calculated from the SPAP. Similar measurements were carried out in 25 nasal breathing (NB) individuals.

RESULTS: The mean MPAP and SPAP were higher in the MB than in the NB group (17.62±2.06 [ATH] and 17.45±1.25 [AR] vs. 15.20±2.36 [NB] mmHg, p<0.005, and 25.61±3.38 [ATH] and 25.33±2.06 [AR] vs. 21.64±3.87 [NB] mmHg, p<0.005, respectively) and the mean acceleration time of pulmonary flow trace (Act) was higher in the NB than in the MB group (127.24±12.81 [RN] vs. 114.06±10.63ms [ATH] and 117.96±10.28 [AR] MS [AR]; p<0.0001).

CONCLUSION: None of the MB children (ATH and AR) met the PH criteria, although individuals with both ATH and isolated AR showed significant evidence of increased pulmonary artery pressure by Doppler echocardiography in relation to NB individuals. No differences were observed between the ATH and AR groups.