An Examination of Crochetage Patterns in Electrocardiograms in Patients with a Secundum Atrial Septal Defect

Abstract

Background: Many pediatric patients with ASD have neither clinical symptoms nor specific findings on ECG. We studied to determine the prevalence of the crochetage pattern and clarify the clinical significance of this finding in the pediatric patients with ASD.
Methods and Patients: We analyzed the ECGs obtained from 151 preoperative pediatric patients with ASD. These ECGs were compared with 339 non-ASD control patients. The crochetage pattern was defined as notch on the R wave in inferior limb leads. We determined the sensitivity and specificity of the crochetage pattern and investigated the correlation between the prevalence of the crochetage pattern and the severity of Qp/Qs.
Results: The sensitivity and specificity of the crochetage pattern in all three inferior limb leads were 11.3％ and 100％ with all control groups combined. The prevalence of the crochetage pattern was high, especially in older group (≥ 10 years old). In hemodynamic study, the prevalence of the crochetage pattern in the patients with Qp/Qs ＞ 3.0 was higher than with Qp/Qs ≤ 1.5 (p ＝ 0.003).
Conclusion: The specificity was remarkably high when the crochetage pattern presented in all three inferior limb leads in the patients with ASD. In addition, the prevalence of the crochetage pattern was high when the patients had severe grade of left-toright shunt and reached the old age group. Therefore, we thought the crochetage pattern could be the useful tool for the electrocardiographic diagnosis of ASD in the childhood.