Cervical origin of the subclavian artery: Echocardiographic diagnosis in patients with monosomy 22q11

Objective: To assess the sensitivity and specificity of echocardiography in the detection of anomalies of the subclavian artery (cervical origin, aberrant origin from the descending aorta or isolation) in patients with monosomy 22q11. Method: From 1/1998 until 03/2002 we examined 57 patients with conotruncal cardiac malformations. 30 patients had pulmonary atresia and ventricular septal defect (53%),13 interrupted aortic arch (23%), 9 tetralogy of Fallot (16%) and 5 common truncus arteriosus (9%). Echocardiographic examination included identification of the laterality of the aortic arch as well as examination of the origin of the brachiocephalic vessels. The results were compared with angiographic and intraoperative findings. Median age at echocardiographic investigation was 74 days (range 1 d - 33.4 yrs.). Results: Laterality of the aortic arch was assessed correctly in all patients. 20/57 patients had a right-sided aortic arch (35%). Echocardiography detected all anomalies of the subclavian artery (14/57 patients, 25%, sensitivity 100%) and excluded these anomalies correctly in 43 patients (specificity 100%). Exact classification of the anomaly of the subclavian artery was possible in 6/6 patients with a cervical origin of the artery and in 7/8 patients with aberrant origin from the descending aorta. Monosomy 22q11 was diagnosed in 21 patients (37%). Conclusion: Echocardiography achieves a high sensitivity in the detection of anomalies of the subclavian artery. The diagnosis of cervical origin of the artery, in particular, can be easily established. As this anomaly appears to be a specific marker for monosomy 22q11, echocardiography facilitates reliable identification of these patients in clinical practice.