Congenital heart defects in patients with isolated microtia: evaluation using colour Doppler echocardiographic image.

Background: The objective of this study was to delineate the characteristics and incidence of congenital heart disease (CHD) in patients with isolated microtia and to determine whether the prevalence of CHD among patients with isolated microtia increases with the severity of microtia.

Methods: A total of 804 consecutive patients had a pre-operative colour Doppler echocardiographic examination. A retrospective study was performed with the clinical and imaging data from November, 2017 to January, 2019. The χ2 test was performed to analyse the interaction between isolated microtia and CHD.

Results: With the colour Doppler echocardiographic examination's data from 804 consecutive isolated microtia patients, we found CHD, including atrial septal defect, ventricular septal defect, tetralogy of Fallot, patent ductus arteriosus, and others, occurred in 52 of 804 patients (6.5%). Atrial septal defect prevalence in patients with isolated microtia was significantly higher than ventricular septal defect (24/804 versus 11/804, p < 0.05) and patent ductus arteriosus (24/804 versus 2/804, p < 0.001). Ventricular septal defect prevalence in patients with isolated microtia was significantly higher than patent ductus arteriosus (11/804 versus 2/804, p < 0.05). All four types of microtia (concha-type microtia, small concha-type microtia, lobule-type microtia, and anotia) had similar incidences of CHD with no difference in the incidences among these types (p > 0.05 respectively). Furthermore, there was no significant difference in the incidence of the atrial septal defect among the four subtypes (p > 0.05 respectively). Similarly, ventricular septal defect and patent ductus arteriosus also showed no differences (p > 0.05 respectively).

Conclusions: The overall incidences of CHD and three most common CHD subtypes (atrial septal defect, ventricular septal defect, and patent ductus arteriosus) in patients with isolated microtia are higher than general population. The prevalence of CHD among patients with isolated microtia does not increase with the severity of microtia. According to our experience in this study, we suggest colour Doppler echocardiographic imaging should be performed for isolated microtia patients soon after birth if possible. Furthermore, for the plastic surgeon and anaesthesiologist, it is important to take pre-operative colour Doppler echocardiographic images which can help evaluate heart function to ensure the safety of the peri-operative period. Future studies when investigating CHDs associated with isolated microtia could focus on genetic and molecular mechanisms.