Intermodality agreement between TTE and low kVp ECG-gated MDCTA in diagnosis of complex CHD in pediatrics

Abstract

Background: Transthoracic echocardiography (TTE) is considered the primary diagnostic modality in congenital heart disease (CHD). However, it has limited role in evaluation of extra-cardiac major vessels abnormalities. Cardiac catheterization angiography is considered the gold standard investigation, yet, it is invasive. The aim of this study is to evaluate the agreement between TTE and low kVp ECG-gated cardiac multi-detector CT angiography (MDCTA) in detecting cardiac and extra-cardiac findings of complex congenital heart disease in a sample size of 36 patients (19 males and 17 females) with an age ranged between 30 days and 12 years (mean age 25.5 months). All cases were diagnosed to have complex CHD clinically and by TTE then referred to undergo cardiac low kVp ECG-gated MDCTA to confirm diagnosis and for better assessment of extra-cardiac major vessels abnormalities. Data derived from both modalities were then compared to calculate the inter-technique variability by using Cohen’s kappa statistics. Results: TTE diagnosed 96% of intra-cardiac anomalies and only 54% of extra-cardiac major vessels anomalies detected by MDCTA, with variable degrees of intermodality agreement in detection different anomalies ranging between perfect agreement in diagnosing most of intra-cardiac lesions and very poor agreement in diagnosing extra-cardiac SVC anomalies. Conclusion: Low kVp ECG-gated cardiac MDCTA is a rapid, non-invasive and reliable diagnostic modality in complex congenital heart diseases. It confirms TTE findings in intra-cardiac anomalies and significantly surpasses TTE reliability in diagnosis of extra-cardiac major vessels anomalies. So, it is indispensable as part of adequate preoperative assessment algorithm in cases of complex CHD and can't be replaced by TTE even with the later providing accurate assessment of intra-cardiac anomalies.