Defective T wave combined with incomplete right bundle branch block: a new electrocardiographic index for diagnosing atrial septal defect

Background Incomplete right bundle branch block (ICRBBB) is commonly associated with atrial septal defect (ASD), but lacks sufficient diagnostic test characteristics. An abnormal T wave is also often observed in ASD, with horizontal or inverted displacement of the proximal T wave limb in the right precordial leads, termed "defective T wave" (DTW). Methods We examined the diagnostic test characteristics of combining ICRBBB with DTW as a new index to diagnose ASD. A total of 132 consecutive patients with ASD and 132 cases of age/gender-matched controls without ASD were enrolled. Results Sensitivities of DTW, ICRBBB, and both were 87.1%-87.9%. Specificities were 97.0%, 96.2%, and 100%, respectively. Positive predictive values were 1.3%, 1.1%, and 100.0% respectively, while negative predictive values were 99.9% for each. Conclusion Combining ICRBBB with DTW in electrocardiogram (ECG) as a new index significantly increased the specificity and positive predictive values while maintaining a high sensitivity in diagnosing ASD. Chin Med J 2012;125(6):1057-1062