64-Multidetector CT Angiographic Assessment of Patterns of Pulmonary and Systemic Venous Drainage in Infants and Children with Complex Congenital Heart Disease

Abstract

SUMMARY AND CONCLUSION S ince the introduction of MDCT in 1998, it played a major role in improving the management of patients with congenital heart disease. It gives us a good visualization of the thoracic vessels, allowing the detection of many anomalies of the aorta and its branches, and the pulmonary and systemic veins. Anomalies of the pulmonary veins are variable and can be either anomalies in the number of viens, the site of drainage, or stenosis along their course or at the point of their entrance into the atrium. Anomalies of the systemic veins include anomalies of the SVC, that might be doubled, running abnormal course or receiving abnormal tributaries. The IVC might be interrupted with absence of its intrahepatic or suprahepatic segment or it might be receiving abnormal tributaries or having different end point. These anomalies in the pulmonary and systemic venous drainage, can be isolated anomalies without other cardiac defects or can be associated with other cardiac defects. Detection of these anomalies correctly and at appropriate time, allows good planning for the patient medical and surgical management. Complex congenital heart defects are CHD with 3 or more cardiac defects. The additional presence of anomalies in the pulmonary and systemic veins add to the complexity of these lesions and carry a cardiosurgical risk. MDCT angiography has the advantage of being a rapid and sensitive scan. It takes around 15 seconds only, giving good images with high temporal and spatial resolution, that allow 3D reconstruction. It can be done even in severely ill patient without the need for general anesthesia. It is also non invasive if compared to conventional angiography, so it doesn’t carry the risk of vascular injury, thrombosis, infection or bleeding at puncture site. The main disadvantage of MDCT is the radiation exposure than can be minimized by decreasing the tube current and using ECG gated technique. The aim of this cross-sectional study was to assess the pattern of systemic and pulmonary veins, in patients with complex congenital heart diseases, using MDCT angiography as compared to echocardiography. Thirty patients with complex CHD were recruited from the pediatric cardiology clinic, at children’s hospital, at Ain Shams university. Each patient was fully assessed by having complete mediacl history recording, full clinical examination, measurement of oxygen saturation, chest X-ray, ECG, echocardiography with colour Doppler and 64-MDCT angiography. All these data where statistically analyzed, to find the percentage of the venous anomalies, their distribution in the studied sample according to age, sex and original cardiac lesion. The study found that 6.6 % of the patients had PAPVC and 3.3 % of them had TAPVC, which is a high percentage if compared to other studies. We didn’t find any relation to the patient age or sex. The study revealed that PAPVC was associated with partial atrioventricular canal, Fallot tetralogy, aortic coarctation and hypoplastic aortic arch, which are all rare association as mentioned in previous literature. TAPVC was associated with common atrioventricular canal and TGA and pulmonary atresia, this rare association is clinically significant as it decrease the severity of cyanosis of TGA. Both echocardiography and MDCT angiography were able to detect the presence of anomalies in the pulmonary venous drainage, but only the MDCT angiography was able to detect the details of the pulmonary veins course from origin to the end point. As regards the systemic veins 43% of our patients were found to have abnormalities seen by MDCT angiography , the most common anomaly was left persistent SVC in 33.3% of the study group. There was a higher association between the presence of left persistent SVC and both common atrioventricular canal and DORV.