Objective: Adenotonsillar hypertrophy (ATH) causing upper airway obstruction and obstructive sleep apnea (OSA) syndrome and may lead to the pulmonary hypertension and cor pulmonale. This study was designed to determine the clinical value of right ventricular (RV) myocardial performance index (MPI) in ATH. The effects of adenotonsillectomy on MPI were also assessed.
Methods: Twenty-one children with grade 3 and grade 4 ATH and 21 age-and-sex matched healthy children were enrolled. MPI, defined as the sum of isovolumetric contraction and relaxation time divided by ejection time, was measured by using Doppler echocardiography preoperatively and postoperatively in all subjects. The quality of life in children was also assessed with obstructive sleep disorder questionnaire (OSA-18).
Results: The RV MPI in patients with ATH was significantly higher than the control group (0.41 +/- 0.06 vs. 0.29 +/- 0.07; P < .001). It showed a strong correlation with mean pulmonary artery pressure and OSA-18 survey score (r = 0.71; P < .005 and (r = 0.64; P < .01, respectively). The RV MPI and OSA-18 survey score decreased significantly after the relief of upper airway obstruction by adenotonsillectomy (from 0.41 +/- 0.06 to 0.31 +/- 0.03; P < .001 and from 83 +/- 27 to 36 +/- 12; P < .0001, respectively). The RV MPI in postoperative group was similar to control group.
Conclusion: Our findings support that advanced stage of ATH is associated with impaired RV functions, which were recovered postoperatively.