Application of prospectively electrocardiograph-gated 128-slice spiral CT angiography in children with complex congenital heart disease

Abstract

Objective To evaluate the prospective electrocardiograph (ECG) -gated 128-slice spiral CT angiography in the diagnosis of complex congenital heart disease and airway abnormality in children. Methods Eighty children with congenital heart disease received prospective (n=40) or retrospective ECG-gated 128-slice spiral CT angiography (n=40).All of the patients underwent ultrasound cardiogram (UCG) within one week before CTA exmination.The image quality and the effective radiation dose were statistically analyzed using independent samples t test andχ2test.The surgical results were taken as the diagnostic standards,and the preoperative prospective and retrospective CT angiography data were compared with UCG results usingχ2test. Results The effective dose of prospective ECG-gated CT angiography[ (1.00±0.26) mSv] was reduced by 86% as compared with the retrospective ECG-gated CT angiography[ (7.37±0.52) mSv] (t=69.296,P 0.05).The definitive diagnosis of extracardiac vascular anomalies was made in 98.3% (59/60) of patients by using prospective and retrospective ECG-gated CT angiography,which were significantly superior to UCG results[ (76.7% (46/60),76.7% (45/59),respectively] (χ2=13.144,12.644,P 0.05).The definitive diagnosis of the cardiac/large-vessel malformations was made in 100% of the patients by both prospective and retrospective ECG-gated CT angiography,and there was no significant difference between 128-slice spiral CT angiography results and UCG results[97.2% (35/36),97.3% (36/37),respectively] (χ2=1.014,0.001,P>0.05).In the cardiac malformations,the definitive diagnosis by prospective and retrospective ECG-gated CT angiography was 88.7% (47/53) and 92.5% (49/53),and there was no significant difference between 128-slice spiral CT angiography results and UCG results[98.1% (52/53),98.1% (52/53),respectively] (χ2=3.824,1.889,P>0.05),and no significant difference in the definitive diagnosis was observed between prospective and retrospective ECG-gated CT angiography (χ2=0.442,P>0.05).In addition,the 128-slice spiral CT angiography detected airway abnormality in 9 cases who underwent prospective or retrospective ECG-gated CT angiography. Conclusion The prospective ECG-gated 128-slice spiral CT angiography exhibits great application value in the preoperative diagnosis of complex congenital heart disease,which helps to develop surgical program and evaluate surgical risks. Key words: Heart defects,congenital; Tomography,X-ray computed; Child; Infant; Radiation dosage