Congenital heart disease frequency in children undergoing MDCT angiography; a 4-year tertiary care hospital experience from Kabul, Afghanistan

Objectives: Echocardiography and cardiac angiography are two main imaging modalities used for evaluating congenital heart diseases (CHDs). Evaluation of CHDs is now possible with Multidetector CT (MDCT) angiography in Afghanistan. To the best of researchers' knowledge, no published data is available on frequency of CHDs among children undergoing chest MDCT angiography in Afghanistan; hence, this study is first of its nature to be conducted in this context. To describe the frequency of CHDs among children who underwent chest MDCT angiography in radiology department at French Medical Institute for Mothers and Children (FMIC) from April 2010 to July 2014. Methods & materials: A retrospective, cross-sectional descriptive study was conducted at radiology department FMIC in Kabul, Afghanistan. The study population consisted of all paediatric patients (aged 1 day–17 years) who underwent chest MDCT angiography at radiology department FMIC from April 2010 to July 2014. All examinations were performed in arterial phase by 128 slice Siemens scanner after intravenous administration of non-ionic water-soluble contrast material (Omnipaque 350) at a volume of 2 ml/Kg. CT setup included non-electrocardiogram gated CT, CT dose index 5–10 and dose–length product 120–200, with post-processing following initial scan. CT reports were reviewed from Radiology Information System. Data collection tool was developed and data were analysed using SPSS v. 22. Frequencies and proportion were calculated for various CHDs. Results: A total of 942 cases of contrast enhanced chest MDCT examinations were performed during this period. Out of these, 212 cases with CHDs were recruited, from which 29 cases were excluded because of undergoing previous surgical procedures or had incomplete CT reports. Remaining 183 cases (n = 183) of CHDs were included for further analysis. A total of 107 patients (58.5%) were male and 76 (41.5%) were female. The patients aged 1 day–17 years (mean age 4.47 + 4.76 standard deviation). A total of 87 patients (47.5%) had solitary anomalies while 96 patients (52.5%) had more than one defect. In terms of location, 20 cases (10.9%) were isolated intracardiac anomalies, 116 cases (63.4%) were isolated extracardiac anomalies and 47 cases (25.7%) had mixed intra- and extracardiac anomalies. Conclusion: Given the frequency, it is clear that CHDs is a complex health problem in Afghan paediatric population. MDCT angiography can be considered as a non-invasive, readily available diagnostic tool in evaluation of complex cardiac anomalies after initial evaluation. Advances in knowledge: MDCT evaluation of CHD as an alternative to echo/angiography has become more important in a country where there is severe shortage of interventional cardiologists.

Objectives: Echocardiography and cardiac angiography are two main imaging modalities used for evaluating congenital heart diseases (CHDs). Evaluation of CHDs is now possible with Multidetector CT (MDCT) angiography in Afghanistan. To the best of researchers' knowledge, no published data is available on frequency of CHDs among children undergoing chest MDCT angiography in Afghanistan; hence, this study is first of its nature to be conducted in this context. To describe the frequency of CHDs among children who underwent chest MDCT angiography in radiology department at French Medical Institute for Mothers and Children (FMIC) from April 2010 to July 2014. Methods & materials: A retrospective, cross-sectional descriptive study was conducted at radiology department FMIC in Kabul, Afghanistan. The study population consisted of all paediatric patients (aged 1 day-17 years) who underwent chest MDCT angiography at radiology department FMIC from April 2010 to July 2014. All examinations were performed in arterial phase by 128 slice Siemens scanner after intravenous administration of non-ionic water-soluble contrast material (Omnipaque 350) at a volume of 2 ml/Kg. CT setup included non-electrocardiogram gated CT, CT dose index 5-10 and doselength product 120-200, with post-processing following initial scan. CT reports were reviewed from Radiology Information System. Data collection tool was developed and data were analysed using SPSS v. 22. Frequencies and proportion were calculated for various CHDs. results: A total of 942 cases of contrast enhanced chest MDCT examinations were performed during this period. Out of these, 212 cases with CHDs were recruited, from which 29 cases were excluded because of undergoing previous surgical procedures or had incomplete CT reports. Remaining 183 cases (n = 183) of CHDs were included for further analysis. A total of 107 patients (58.5%) were male and 76 (41.5%) were female. The patients aged 1 day-17 years (mean age 4.47 + 4.76 standard deviation). A total of 87 patients (47.5%) had solitary anomalies while 96 patients (52.5%) had more than one defect. In terms of location, 20 cases (10.9%) were isolated intracardiac anomalies, 116 cases (63.4%) were isolated extracardiac anomalies and 47 cases (25.7%) had mixed intra-and extracardiac anomalies. conclusion: Given the frequency, it is clear that CHDs is a complex health problem in Afghan paediatric population. MDCT angiography can be considered as a non-invasive, readily available diagnostic tool in evaluation of complex cardiac anomalies after initial evaluation. advances in knowledge: MDCT evaluation of CHD as an alternative to echo/angiography has become more important in a country where there is severe shortage of interventional cardiologists. Conventional angiography; the formerly accepted gold-standard for detection of CHDs is now uncommonly performed for diagnostic reasons alone. 4 Its main limitations are two-dimensional nature, relatively invasive approach, need for larger volume of intravascular contrast material, frequent need for general anaesthesia and greater radiation dose compared to CT. 4,5 Also, specialist availability, especially interventional cardiologist also needs to be accounted for in a country like Afghanistan.
CT and MRI can be used as non-invasive modalities, especially in the evaluation of pre-and post-operative cardiovascular anatomy. 6 Cardiac CT examination can accurately depict intraand extracardiac anomalies. 6 Newer CT scanners yield images with better temporal and spatial resolution, greater anatomic coverage per rotation and more consistent enhancement with a lesser volume of intravascular contrast material, and higher-quality two-dimensional reformation and three-dimensional reconstruction owing to acquisition of an isotropic data set. 7 Evaluation of CHDs is now possible with MDCT angiography in Afghanistan. To the best of researchers' knowledge, no published data is available on frequency of congenital heart diseases among children undergone chest MDCT angiography in Afghanistan; hence, this study is being the first of its nature conducted in this context. Information generated from this study is likely to pave the way for further researches in Afghanistan in this field; as well as to promote awareness regarding the rule of MDCT angiography in evaluation of CHDs and frequency of various CHDs among health care professionals and general public.

Objectives
To describe the frequency of congenital heart diseases among children who underwent chest MDCT angiography at radiology department of French Medical Institute for Mothers and Children (FMIC) from April 2010 to July 2014

MeThODs anD MaTerials
A retrospective, cross-sectional descriptive study was conducted at radiology department of FMIC. The study population consisted of all paediatric patients (aged 1 day to -17 years) referred from cardiologist/clinicians who showed signs/symptoms of congenital heart diseases underwent chest MDCT angiography at radiology department of FMIC from April 2010 to July 2014.
All examinations were performed by 128 slice single source Siemens SOMATOM Definition AS scanner with gantry rotation time of 0.33 s. Collimation was made from the thoracic inlet to level of cardiac apex. Reconstruction of smooth, Kernel of 20-30 was performed in mediastinal window. Scans were done in arterial phase after intravenous administration of non-ionic water-soluble contrast material (Omnipaque 350) at a volume of 2 ml/Kg. CT set-up included non-electrocardiogram (ECG) gated CT, CT dose index 5-10 and dose-length product 120-200, with post-processing including axial MPR and virtual rendered technique following initial scan. Bolus tracking was performed. Region of interest was selected aortic was and the scan was stared when the Hounsfiedl unitHU reached 200. In majority of the cases sedation was not need. A smaller number of cases were given rectal Midazolam (1 mg/Kg).
CT reports were reviewed from Radiology Information System (RIS) by certified radiologist with 5 years of experience. The patients were referred by clinicians of different specialties for various reasons (cardiovascular, respiratory, traumatic and neoplastic processes) from over the country. Data collecting tool was developed and data were analyzed using SPSS v. 22.
Frequencies and proportion were calculated for various CHDs.

Inclusion criteria
All paediatric patients (aged 1 day-to 17 years) who underwent chest MDCT angiography at radiology department of FMIC from April 2010 to July 2014 following referral from cardiology/ allied clinicians.

Exclusion criteria
Patients with known CHDs who had undergone any treatment procedure and patients with incomplete CT reports resulTs In total, 212 cases with CHDs were recruited. Out of these, 29 cases were excluded as patients had undergone previous surgical procedures or did not have complete CT report. Remaining 183 case of CHDs were included for further analysis. Male to female ratio was 107 (58.5%) and 76 (41.5%) respectively. Patients age ranged from 1 day to 17 years (mean age 4.47 + 4.76 SD).
VSD: isolated VSD was detected only in four cases, while VSD as part of Tetralogy of Fallot (ToF) was seen in 32 cases, VSD combined with pulmonary trunk atresia (PTA) in five cases, VSD with total anomalous pulmonary venous connection (TAPVC) in two cases, VSD with CoA in two cases (one of which was VSD with CoA+ASD), VSD with interrupted aortic arch (IAA) + ASD in one case, VSD with ASD in one case, VSD with patent ductus ASD: from the total 18 cases of ASD only three cases were isolated entities while 11 cases were associated with total anomalous pulmonary venous connection (TAPVC), three cases with VSD and one case with LPSVC ( Figure 1) ( Table 2).
Aortic anomalies (AA): (Table 3) A total of 80 case were diagnosed as AA; 58 cases had anomalies in calibre [CoA, IAA and PCoA) while 19 cases had anomalies in orientation (RtAA), one case both in calibre and orientation (RtAA+CoA) and one case being anomalous in origin (Truncus arteriosus). Coarctation of Aorta (CoA): the most common congenital defect was CoA (35 cases). Out of these, 21 cases of CoA were isolated anomalies while 14 cases were associated with other intra or extracardiac anomalies (Table 3).
IAA: interrupted aortic arch was the second most frequent pathology of aorta with 12 cases (Figure 2). Isolated IAA was Percentages were not calculated in "part affected anomalies" as some case(s), who had more than one anomaly, have been counted twice.  seen in four cases while eight cases of IAA were combined with other intra-or extracardiac anomalies (Table 3). Pseudocoarctation of Aorta (PCoA): the next frequent anomaly of aortic arch was pseudocoarctation with a frequency of 11 cases. Isolated PCoA was seen in two cases while remaining nine cases were associated with other intra-or extracardiac anomalies (Table 3).
Hypoplastic aortic root was detected in one case and hypoplastic aortic arch also in one case.

RtAA
From total 20 cases of anomalously oriented aortic arch; three cases were isolated entities while the remaining 17 cases were combined with other intra or extra cardiac anomalies (Table 3).
ToF: from total 32 cases of ToF, 10 cases were isolated ToF while 22 cases had other simultaneous defects: 12 cases were associated with RTAA, 4 cases were associated with hypoplastic pulmonary trunk (HPT), 2 cases with left persistent superior vena cava (LPSVC), 1 case with pseudocoarctation of aorta (PCoA), 1 case with DC, 1 case with PDA and 1 case with LPSVC, partial anomalous pulmonary venous return (PAPVR) and situs inversus (SI). Pulmonary artery (PA) anomalies: a total of 18 patients had anomalies in PA (Figure 3). Pulmonary trunk atresia (PTA) was detected in eight cases, hypoplastic pulmonary trunk (HPT) in six cases, unilateral pulmonary artery atresia (UPAA) in two cases and anomalous origin of unilateral pulmonary artery (AOUPA) in two cases. PTA with VSD was seen in six cases. Out of six cases of PTA + VSD, one case was associated with PAPVR and one case with DC. In this PTA subgroup of eight cases, four cases were associated with major aortopulmonary collateral arteries (MAPCAs). PTA with intact interventricular septumIVS was seen in two cases.

Hypoplastic Pulmonary Trunk (HPT)
From total six cases of HPT, four cases were associated with ToF, one case with DC, one case with associated hypoplasia of right and left pulmonary arteries. four cases in HPT group had   (Table 4).
Abnormal aortopulmonary communications ( Table 5) a total of 71 patients had abnormal aorto-pulmonary connection. Patent ductus arteriosus (PDA) was the commonest type of abnormal aorto-pulmonary connection with 56 cases, followed by MAPCA 13 cases and AOUPA with 2 cases (Table 5). PDA: out of total 56 PDA cases, half of the cases (28), it was seen as isolated CHD, while in second half, PDAs were associated with other anomalies as described in Table 5. MAPCAs: total 13 cases of MAPCAs were seen. 7 cases combined with ToF, 5 cases combined with PTA and in 1 case was seen with HPT.
Anomalous pulmonary venous connection (APVC) ( Table 6) A total of 20 cases had APVC, 13 cases of TAPVC and 7 cases of PAPVC. The TAPVC was supracardiac in majority of cases (n = 10) while it was infracardiac in two cases and cardiac in one case. TAPVC was associated with ASD in 11 cases and with VSD in 2 cases.
PAPVR was an isolated entity in five cases while it was associated with PTA in one case and with ToF+SI in another case (Table 6).  (Table 7).

DiscussiOn
The study demonstrates that various CHDs are fairly prevalent among Afghan paediatric population. More than half of the patients had more than one congenital heart defect(s). Aortic anomalies were the most common entities. As echocardiography is poor in evaluation of aorta, therefore patients with suspected aortic anomalies usually underwent CT. It is however, important to point out that cardiac MRI is not available in Afghanistan at the time of this study was undertaken, which leaves MDCT as the only cross-sectional modality available to investigate congenital lesions in this cohort.
CoA was the commonest aortic anomaly in our cases which is reported to account 5-7% of all CHDs. 8 MZ Al-Azzazy reported that MDCT angiography with multiplanar and three dimensional techniques can be considered the modality of choice for pre-operative assessment of paediatric aortic coarctation. 9 CoA with RtAA reported to be an exceedingly rare congenital anomaly 10 was seen in one of our cases which was also associated with ToF.
Intracardiac lesion however reported the commonest CHDs, were less frequently detected in our study. This could be explained on the basis that ECG has the sensitivity of 100% in detection of intracardiac lesions compared to 85% sensitivity of non-ECG getting CT, 9 therefore patients with isolated intracardiac defects without high suspicious for extracardiac defects should not routinely undergo CT. However, when planning for surgery, MDCT is useful for detection of other associated defects with for example, a single VSD, as an alternative to MRI. Also, in contrast to MRI, MDCT affords advantages, such as less scan time, minimal to no sedation, extremely useful in scanning of very small critically ill infants.
Right-sided aortic arch which is reported to occur in <0.1% of the population 11 was detected in 20 of our patients. As the mirror type of RtAA is commonly associated with cyanotic heart disease, 12 it was associated with ToF in almost half of the cases (nine cases) ( Table 3).
ToF that consists of 7-10% of all CHDs 13 was present of 32 of our cases. RtAA that is reported to be present in one-quarter of patients with ToF 13 was present in more than one-quarter of our patients; 12 out of 32 (Table 4).
AOUPA branch from the ascending aorta accounts for only 0.12% of all CHDs. 14 Right aortic arch is reported as a common association of left AOUPA 14 as in our case (Table 4).