congenital heart disease ( chd ) is the most frequent type of congenital birth deficiency disease , with an incidence of 8% among newborns . chd is caused by many factors , including intrauterine infection , environmental pollution , and inheritable factors . it was reported that the primary cause of mortality from birth defects was related to the structure or function of the heart lesion . however , the pathogenesis of the chd is extremely complex and the association between maternal age and chd has not been confirmed yet . acute chd is hypothesized to be associated with genetics and environmental factors , and the life expectancy of patients has always been short because of the absence of surgical and medical therapies . fast and accurate diagnosis and timely intervention and therapy of chd can remarkably improve cardiac function , ameliorating the poor prognosis and problems such as neurodevelopment delay . in recent years , prenatal diagnosis of chd has greatly improved the survival rates of children via decreasing the risk of complications . as a consequence , timely and accurate preoperative diagnosis is crucial for both prevention and treatment of chd . accordingly , echo is the criterion standard and first - line diagnostic technique in diagnosing patients with chd . for example , fetal echocardiography plays an important role in classifying the chds in utero , allowing patients to be classified as having major , minor , or no chd based on the echocardiographic results . although echocardiography is mostly applied among high - risk pregnant women , it still is not currently a routine prenatal screening tool . fetal echocardiography is only based on limited indications , which can result in some chds going undetected , thereby increasing risk of early neonatal mortality . msct provides detailed , minimally invasive diagnosis and data on coronary artery anatomy in infants , children , and adults with chd [ 1214 ] . the ongoing advances of msct in diagnostic modality include evaluation of aortic disease , pericardial disease , cardiovascular function , and coronary artery plaque imaging . furthermore , 64-msct can be equipped with cardiac defibrillators , pacemakers , and other helpful implants in patients in which echo examination may be contraindicated . use of 64-msct improves the limitations of catheter angiography since the acquisition of natural volumetric analysis allows visualization of 3-dimensional spatial images such as the anomalous coronary coursing among the great arteries . however , one of the potential disadvantages of 64-msct is the nephrotoxic ionizing radiation . as diagnostic approaches , echo and 64-msct both have advantages and limitations . several studies have compared the performance of echo and 64-msct in coronary artery disease ( cad ) patients as the target population , showing that left ventricular ( lv ) systolic function assessed by 64-mdst is very comparable to 2-month 2-dimensional ( 2d ) echocardiography ( tte ) , and lv function is a powerful indicator of cad . among chd subjects , however , few studies have meticulously compared 64-mdst and echo in terms of cardiac malformation , malformation in the connecting area between heart and large vascular , and large vascular malformation . therefore , this study investigated whether echo and 64-msct have a synergetic effect in chd diagnosis and evaluated the accuracy of echo and 64-msct . subjects were excluded if : ( 1 ) they were aged more than 5 years old ; or ( 2 ) they weighed more than 30 kilograms ; ( 3 ) they suffered from renal disease ( more than 150 mmol / l of serum creatinine ) ; ( 4 ) they had non - sinus rhythm ; or ( 5 ) they were allergic to iodinated contrast media . the chd was divided into 3 types  cardiac malformation , heart - large vascular connecting malformation , and large vascular malformation  based on van praagh segmental analysis . cardiac malformation includes atrial septal defect , ventricular septal defect , single atrium , single ventricle , right ventricular outflow tract stenosis , mitral deformity , and tricuspid valve subdisplacement malformation . malformation in the connecting area between heart and large vascular consists of overriding aorta , complete transposition of the great arteries , aortic valve deformity , pulmonary valve malformation , and double outlet of ventricle . large vascular malformation comprises aortic root dilatation , aortic coarctation , interruption of aortic arch , and dilation of pulmonary artery . echo was performed using the diamond select ie33 ultrasound system ( philips medical systems , netherlands ) . cardiac functions were measured using multiple imaging modalities , such as biplanar 2d echo , 2d color flow doppler imaging , and conventional b - mode 2d echo . echo often started with subcostal an acoustic window or subcostal acoustic window , and the major cardiovascular structures were assessed according to van praagh segmental analysis . patients were given oral chloral hydrate solution with a dosage of 50 mg / kg . the 64-msct examination was performed by somatom perspective ( siemens , germany )   with tube voltage of 80100kv , tube current of 80100 mas ( varied during acquisition and according to the weight of the children ) , pitch of 1.2 , and 0.6 mm collimation . a contrast medium dosage was 1.22.0 ml / kg ( omnipaque 350 mg / ml ) followed by the same volume of saline chaser with an injection rate of 11.5 ml / s . bolus tracking was applied to determine acquisition delay ( the roi was the aortic sinus , trigger - threshold 80 hu ) . for all patients , the effective thickness was 1 mm and the reconstructive interval was 0.6 mm . for image reconstruction , all the data were transferred to syngo multi - modality workplace ( siemens , germany ) . we used multi - planar reconstruction ( mpr ) , volume render ( vr ) , and maximum intensity projection ( mip ) to process images . the echo and 64-msct images were analyzed by 4 experienced cardiologists with at least 8-year clinical practices . the typical echo image for chd is shown in figure 1 , which consists of mid - muscular ventricular septal defect and tetralogy of fallot . a typical 64-msct image is shown in figure 2 , in which the pulmonary trunk , a periphery pulmonary stenosis , vsd and right ventricular hypertrophy , pulmonary arteriovenous fistulas , and many pulmonary side branches arising from aorta can be seen . subjects were excluded if : ( 1 ) they were aged more than 5 years old ; or ( 2 ) they weighed more than 30 kilograms ; ( 3 ) they suffered from renal disease ( more than 150 mmol / l of serum creatinine ) ; ( 4 ) they had non - sinus rhythm ; or ( 5 ) they were allergic to iodinated contrast media . the chd was divided into 3 types  cardiac malformation , heart - large vascular connecting malformation , and large vascular malformation  based on van praagh segmental analysis . cardiac malformation includes atrial septal defect , ventricular septal defect , single atrium , single ventricle , right ventricular outflow tract stenosis , mitral deformity , and tricuspid valve subdisplacement malformation . malformation in the connecting area between heart and large vascular consists of overriding aorta , complete transposition of the great arteries , aortic valve deformity , pulmonary valve malformation , and double outlet of ventricle . large vascular malformation comprises aortic root dilatation , aortic coarctation , interruption of aortic arch , and dilation of pulmonary artery . echo was performed using the diamond select ie33 ultrasound system ( philips medical systems , netherlands ) . cardiac functions were measured using multiple imaging modalities , such as biplanar 2d echo , 2d color flow doppler imaging , and conventional b - mode 2d echo . echo often started with subcostal an acoustic window or subcostal acoustic window , and the major cardiovascular structures were assessed according to van praagh segmental analysis . patients were given oral chloral hydrate solution with a dosage of 50 mg / kg . the 64-msct examination was performed by somatom perspective ( siemens , germany )   with tube voltage of 80100kv , tube current of 80100 mas ( varied during acquisition and according to the weight of the children ) , pitch of 1.2 , and 0.6 mm collimation . a contrast medium dosage was 1.22.0 ml / kg ( omnipaque 350 mg / ml ) followed by the same volume of saline chaser with an injection rate of 11.5 ml / s . bolus tracking was applied to determine acquisition delay ( the roi was the aortic sinus , trigger - threshold 80 hu ) . for all patients , the effective thickness was 1 mm and the reconstructive interval was 0.6 mm . for image reconstruction , all the data were transferred to syngo multi - modality workplace ( siemens , germany ) . we used multi - planar reconstruction ( mpr ) , volume render ( vr ) , and maximum intensity projection ( mip ) to process images . the echo and 64-msct images were analyzed by 4 experienced cardiologists with at least 8-year clinical practices . the typical echo image for chd is shown in figure 1 , which consists of mid - muscular ventricular septal defect and tetralogy of fallot . a typical 64-msct image is shown in figure 2 , in which the pulmonary trunk , a periphery pulmonary stenosis , vsd and right ventricular hypertrophy , pulmonary arteriovenous fistulas , and many pulmonary side branches arising from aorta can be seen . the diagnostic accuracy and kappa value of echo and 64-msct diagnoses were evaluated based on the operation results . the measurement data are all presented as mean value  standard deviation ( sd ) . kruskal - wallis test were carried out to compare differences in continuous data among groups . the accuracy of the 2 methods was evaluated using mcnemar  test , while the uniformity was evaluated using kappa value . receiver operating characteristic curve ( roc ) analysis was conducted to compare diagnostic area under the roc ( auc ) values of the 2 methods . the mean age of the cohort was 6.2 years old , ranging from 4 to 13 years old . the mean body weight was 21.9 kg , and the mean height was 114 cm with a range from 44 to 177 cm . the mean heart rate was 118 beats / min , with a range from 90 to 152 beats / min . baseline characteristics of this cohort are also shown in supplementary table 1 . as seen in table 2 , we detected 697 areas by echo , in which 133 true positives , 553 true negatives , 3 false positives , and 8 false negatives . the results of comparison between echo and 64-msct revealed that there was a significant difference in diagnostic accuracy between the 2 methods ( =9.538 , p=0.023 ) . as table 3 shown , the positive predictive value was 97.80% and negative predictive value was 98.57% . the auc value of echo was slightly larger than that of 64-msct ( 0.982 vs. 0.955 ) . 64-msct detected 690 areas : 128 true positives , 536 true negatives , 8 false positives , and 18 false negatives ( table 2 ) . the diagnostic efficiency , specificity , positive predictive value , and negative predictive values were 94.10% , 98.50% , 94.12% , and 96.75% , respectively , with an accuracy of 96.20% . the 2 methods are consistent with each other in congenital heart disease diagnosis ( kappa=0.950 ) . as seen in table 4 , we found that only 1 case with single atrium was underdiagnosed by echo , while a total of 7 malformations were underdiagnosed by 64-msct , including 1 ventricular septal defect , 2 atrial septal defects , 3 right ventricular outflow tract stenoses , and 1 tricuspid valve subdisplacement malformation . in addition , there were 4 misdiagnosed malformations by 64-msct , including 1 atrial septal defect , 2 right ventricular outflow tract stenosis and 1 tricuspid valve subdisplacement malformation . the diagnostic accuracy of echo and 64-msct were 99.50% and 94.80% , respectively ( =8.578 , p=0.034 ) ( table 5 ) . as seen in table 4 , 1 aortic valve deformity was misdiagnosed , and 1 complete transposition of the great arteries and 1 pulmonary valve malformation of the great arteries were underdiagnosed by echo . 64-msct misdiagnosed 2 aorta saddles and 1 pulmonary valve malformation , and underdiagnosed 3 aorta saddles , 1 complete transposition of the great arteries , 1 anomaly of aortic valve , and 3 pulmonary valve malformations . the diagnostic accuracy of echo and 64-msct were 99.00% and 95.40% , respectively ( =6.779 , p=0.009 ) ( table 6 ) . the kappa coefficient was 0.955 , which suggested that the 2 diagnoses were consistent with each other . as seen in table 4 , 1 interruption of the aortic arch and 1 anomalous inferior vena cava drainage were misdiagnosed . echo underdiagnosed 1 pulmonic stenosis or atresia , 2 patent ducti arteriosus , 1 double superior vena cava , and 1 anomalous inferior vena cava drainage . 64-msct misdiagnosed 1 dilation of pulmonary artery , and underdiagnosed 2 pulmonic stenosis or atresia and 1 double superior vena cava . echo and 64-msct had no significant difference in diagnosing large vascular malformations ( =1.806 , p=0.179 ) ( table 7 ) . the mean age of the cohort was 6.2 years old , ranging from 4 to 13 years old . the mean body weight was 21.9 kg , and the mean height was 114 cm with a range from 44 to 177 cm . the mean heart rate was 118 beats / min , with a range from 90 to 152 beats / min . we detected 697 areas by echo , in which 133 true positives , 553 true negatives , 3 false positives , and 8 false negatives . the results of comparison between echo and 64-msct revealed that there was a significant difference in diagnostic accuracy between the 2 methods ( =9.538 , p=0.023 ) . as table 3 shown , the positive predictive value was 97.80% and negative predictive value was 98.57% . the auc value of echo was slightly larger than that of 64-msct ( 0.982 vs. 0.955 ) . 64-msct detected 690 areas : 128 true positives , 536 true negatives , 8 false positives , and 18 false negatives ( table 2 ) . the diagnostic efficiency , specificity , positive predictive value , and negative predictive values were 94.10% , 98.50% , 94.12% , and 96.75% , respectively , with an accuracy of 96.20% . the 2 methods are consistent with each other in congenital heart disease diagnosis ( kappa=0.950 ) . as seen in table 4 , we found that only 1 case with single atrium was underdiagnosed by echo , while a total of 7 malformations were underdiagnosed by 64-msct , including 1 ventricular septal defect , 2 atrial septal defects , 3 right ventricular outflow tract stenoses , and 1 tricuspid valve subdisplacement malformation . in addition , there were 4 misdiagnosed malformations by 64-msct , including 1 atrial septal defect , 2 right ventricular outflow tract stenosis and 1 tricuspid valve subdisplacement malformation . the diagnostic accuracy of echo and 64-msct were 99.50% and 94.80% , respectively ( =8.578 , p=0.034 ) ( table 5 ) . as seen in table 4 , 1 aortic valve deformity was misdiagnosed , and 1 complete transposition of the great arteries and 1 pulmonary valve malformation of the great arteries were underdiagnosed by echo . 64-msct misdiagnosed 2 aorta saddles and 1 pulmonary valve malformation , and underdiagnosed 3 aorta saddles , 1 complete transposition of the great arteries , 1 anomaly of aortic valve , and 3 pulmonary valve malformations . the diagnostic accuracy of echo and 64-msct were 99.00% and 95.40% , respectively ( =6.779 , p=0.009 ) ( table 6 ) . the kappa coefficient was 0.955 , which suggested that the 2 diagnoses were consistent with each other . 1 interruption of the aortic arch and 1 anomalous inferior vena cava drainage were misdiagnosed . echo underdiagnosed 1 pulmonic stenosis or atresia , 2 patent ducti arteriosus , 1 double superior vena cava , and 1 anomalous inferior vena cava drainage . 64-msct misdiagnosed 1 dilation of pulmonary artery , and underdiagnosed 2 pulmonic stenosis or atresia and 1 double superior vena cava . echo and 64-msct had no significant difference in diagnosing large vascular malformations ( =1.806 , p=0.179 ) ( table 7 ) . based on our results , the diagnostic accuracy of the lesions in the macrovascular structures is different between echo and 64-msct ; echo provided higher diagnosis accuracy in the heart and the heart - macrovascular malformations . thus , we recommend echo diagnosis in the case of heart and the heart - macrovascular malformation , whereas 64-msct is better for macrovascular malformations . in our study , we examined 30 patients diagnosed with both echo and 64-msct . compared with the criterion standard , we found that the diagnostic efficiency of echo and 64-msct is 93.70% and 94.10% , respectively ; with specificity of 99.50% and 98.50% , respectively ; and diagnostic accuracy of 98.40% and 96.20% , respectively . echo displays 2d images , depending on the experience of technicians to monitor and judge the structure and blood flow of the heart and macrovascular structures . 64-msct is mainly used to observe the function of the cardiac ventricular wall and ventricle through electrocardiographically gated layer scanning , and its high scan speed , high resolution , and 3d images significantly facilitate the diagnosis of chd . in diagnosing the malformation in the heart , our results showed that the diagnosis accuracy of echo and 64-msct is 99.50% and 94.80% respectively with a significant difference ( p=0.034 ) . 64-msct had 7 underdiagnoses and 4 misdiagnoses , since 64-msct could not distinguish small atrial septal that are smaller than 5 mm in width . besides , the static images that 64-msct displayed make it difficult to elucidate the structure of cardiac valves or evaluate the dynamic changes precisely . so falsities and misdiagnoses occur when the lesions are at the cardiac valves , in the meantime diagnosing with 64-msct . 64-msct had a higher rate of misdiagnoses in the heart - macrovascular malformation compared with echo . some researchers deemed that 64-msct can not clearly exhibit abnormalities in the heart and macrovascular , and it becomes more complicated when there are artifacts . there is no significant difference in diagnostic accuracy between echo and 64-msct in the case of macrovascular malformation ( p=0.1790 ) . however , there were 5 errors made when diagnosing the abnormality in the macrovascular part using echo . echo displays a 2d image , which relies on the experience of the technicians . due to the acoustical window , it becomes more complex for the technicians to diagnose the abnormality in the macrovascular part by echo . although 64-msct displayed 3d images with high scan speed and high resolution , errors occur in the presence of artifacts when contrast media is used for the abnormal transit . generally , 64-msct may be a better choice than echo when diagnosing lesions in the macrovascular part . one major limitation of this research is the small sample size , and more samples would make the accuracy and specificity of echo and 64-msct in diagnosing chd more reliable . as for the operators , skilled technicians were hired to avoid errors and misdiagnoses as much as possible , which makes our results credible . in conclusion , errors and misdiagnoses occur when diagnosing the lesions in congenital heart disease with echo or 64-msct . in addition , echo has no radiation , which makes it a better choice for children , who are usually very sensitive it . taking the diagnostic accuracy and application into consideration , we recommend echo when diagnosing , rechecking , and following up the lesion in diagnosis of the heart and the heart - macrovascular malformations , while 64-msct is recommended in the diagnosis of macrovascular malformation . our research could serve as the theoretical basis for making a better choice in use of imaging methods when diagnosing chd .
backgroundthe goals of this study were : to compare echocardiogram and 64-multislice spiral computed tomography ( 64-msct ) in diagnosing pediatric congenital heart disease ; to determine the significance of echo for diagnosing congenital heart disease ; and to identify the appropriate diagnosis for congenital heart disease through combined use of 64-msct and echo.material/methodsthirty patients underwent both echo and 64-msct diagnoses before their surgeries . imaging from echo and 
 64-msct were analyzed by 4 specialists . the diagnostic accuracy and kappa value of echo and 64-msct were evaluated based on the operation results . 
 the accuracy of the 2 methods was evaluated using the mcnemar 2 test.resultswe confirmed 138 malformations in 30 children by surgery . 
 the diagnostic accuracy of echo and 64-msct was 98.40% and 96.20% , respectively , with a significant difference between the 2 results ( 2=6.404 , p=0.011 ) . 
 we compared prognosis accuracy and uniformity on 3 types of congenital heart disease ( cardiac malformation , heart - large vascular connecting malformation , and large vascular malformation ) : 56 cardiac malformations were confirmed by surgery , in which the diagnostic accuracy of echo and 64-msct was 99.50% and 94.80% , respectively . 
 ( 2=8.578 , p=0.034 ) ; 31 heart - large vascular connecting malformations were confirmed by surgery , in which the diagnostic accuracy of echo and 64-msct was 99.00% and 95.42% ( 2=6.779 , p=0.009 ) ; and 51 vascular malformations were confirmed , in which the diagnostic accuracy of echo and 64-msct was 96.30% and 98.30% ( 2=1.806 , p=0.179).conclusionsecho is more effective than 64-msct in preoperative diagnosis of congenital heart disease , especially for children .