PURPOSE: To assess the impact of obstructive sleep apnea (OSA) due to adenotonsillar hypertrophy (ATH) on global myocardial performance in children using tissue Doppler imaging (TDI) and to evaluate the reversibility after adenotonsillectomy (AT).
METHODS: We included 42 children with OSA due to ATH (mean age 5±3.14 y) as the study group and 45 age- and sex-matched healthy children (mean age 5.2±3.08y) as the control group. Polysomnography (PSG) and echocardiography were performed. Indexed left ventricular mass (LVMi), pulmonary artery systolic pressure (PASP), mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVR) were calculated by echocardiography. TDI was used to determine the left ventricular (LV) and right ventricular (RV) myocardial performance index (MPI) of included patients before and after AT as well as children in the control group. Patients were classified into mild OSA [Apnea Hypopnea index (AHI) 1-5 (n=18)], moderate to severe [AHI > 5 (n=24)] according to PSG findings. All children in the control group had AHI < 1. Patients were treated by AT then reevaluated by PSG and echocardiographic examination after 6-8 months of surgery.
RESULTS: Patients with ATH had higher PASP, mPAP, PVR, LVMi and right ventricular diastolic diameter (RVDd) than control group. Patients with moderate to severe OSA showed more prominent changes than patients with mild OSA but patients with mild OSA still differed significantly from children in control group. The TDI-derived RVMPI and LVMPI measurements of patients with OSA were higher than those of children in the control group (mean ±SD: 0.40±0.08 vs 0.28±0.009, P<0.001 and 0.45±0.05 vs 0.32±0.05, P<0.001 respectively) and were correlated well with the AHI and mPAP. In addition, mPAP was significantly correlated with AHI. Postoperatively, relief of OSA was validated by PSG and echocardiographic parameters showed no significant difference from control group.
CONCLUSION: TDI-derived MPI can detect early myocardial dysfunction in children with OSAS due to ATH and these changes are reversible by adenotonsillectomy.
CLINICAL IMPLICATIONS: TDI can detect early myocardial dysfunction in children with OSAS due to ATH .
DISCLOSURE: Abdelbaset Saleh, No Financial Disclosure Information; No Product/Research Disclosure Information