Hearing impairment following surgically repaired congenital heart disease in children: a prospective study.

Objectives: To determine the prevalence of sensorineural hearing loss (SNHL) in children who underwent congenital cardiac surgery (CCS) by using a pre- and postoperative hearing test, a conventional audiometry, an extended high-frequency audiometry (HFA) or auditory steady-state response (ASSR), and distortion-product otoacoustic emissions (DPOAE).

Study Design: This prospective study enrolled children with CCS in Siriraj Hospital, Thailand, between 2019 and 2023. Conventional audiometry including HFA or ASSR and DPOAE were performed pre- and postoperatively. The patients with bilateral abnormal hearing loss or an incomplete examination were excluded. Collected data included: demographics, cardiac surgery and ototoxic medication. Prevalence of SNHL by conventional audiometry and subclinical hearing impairment by HFA or DPOAE were ascertained, and risks were analysed.

Results: Ninety-eight patients were eligible for the study. The median age (IQR) was 5.3 (1.5-9.6) years. Fifteen patients (15.3%) had univentricular hearts. The preoperative audiologic test was performed 1 day prior to the CCS. The postoperative test was performed at a median of 4.4 (IQR: 2.7-8.0) months postoperatively. Preoperative unilateral hearing impairments were reported in 17 patients (17.3%). Postoperatively, four patients (4.1%) showed significantly abnormal audiogram (> 25 dB) or 15 dB shift at 250-8000 Hz consistent to a new SNHL. Subclinical hearing impairment by HFA was affected in 10 patients (10.2%). Thirty-three patients (33.6%) had abnormal DPOAE exclusively. Therefore, new SNHL, including subclinical hearing loss, revealed a prevalence of ototoxicity up to 47.9%. Age <1 year at surgery was the independent risk of postoperative SNHL (adjusted OR 18.5, 95% CI 1.2 to 293.8, p=0.04).

Conclusion: Routine post-CCS audiological surveillance especially CCS in infancy is recommended for early recognition and timely management based on the 43.8% subclinical and the 4.1% SNHL that was found in this study.

Trial Registration Number: TCTR20200421001.