|Year : 2013 | Volume
| Issue : 4 | Page : 462-467
Pattern and clinical profile of children with complex cardiac anomaly at University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu State, Nigeria
JM Chinawa1, HA Obu1, CB Eke1, JC Eze2
1 Department of Pediatrics, College of Medicine, University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu State, Nigeria
2 Department of Surgery, College of Medicine, University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu State, Nigeria
|Date of Acceptance||25-Nov-2012|
|Date of Web Publication||23-Aug-2013|
J M Chinawa
Department of Pediatrics, University of Nigeria Teaching Hospital, PMB 01129, Enugu, Enugu State - 400 001
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: Complex congenital cardiac abnormalities are rare among children and contribute to mortality and morbidity. The prevalence and pattern of presentation vary from place to place.
Materials and Methods: The objective of this study was to determine the clinical profile and pattern of presentation of complex congenital cardiac malformations among children attending a tertiary hospital in Enugu State. A cross-sectional retrospective study in which a review of the records of children who attended the children outpatient clinic of University of Nigeria Teaching Hospital (UNTH), Ituku-Ozalla, Enugu State over a 5-year period (January 2007-June 2012) was undertaken.
Results: Thirty one thousand seven hundred and ninety-five (31,795) children attended the outpatient clinic of the hospital over the study period, of these, 65 had cardiac diseases, from which 16 were found to have congenital complex cardiac abnormalities of various types, giving a prevalence of 0.05%.
Complex abnormalities seen in these children are Tricuspid atresia with various associations, cor triatriatum, single ventricle, and large ASD (atrio-septal defect) with complete AVCD, cor triatriatum sinistrum with cardiomyopathy, DORV (double outlet right ventricle) with left sided aorta, hypoplastic tricuspid valve with a PDA (patent ductus artriosus), TOF (tetralogy of fallot), prolapse of aortic valve, and pulmonary regurgitation. One of these complex cardiac anomalies presented with Turner's syndrome and another with VACTERAL association.
Conclusions: The results of this study show that 0.05% of children who presented at cardiology clinic of a teaching hospital in Enugu State had congenital complex cardiac abnormalities and that the commonest forms seen were those with cor triatriatum and TOF.
Keywords: Abnormalities, children, complex congenital cardiac, Enugu, presentation
|How to cite this article:|
Chinawa J M, Obu H A, Eke C B, Eze J C. Pattern and clinical profile of children with complex cardiac anomaly at University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu State, Nigeria. Niger J Clin Pract 2013;16:462-7
|How to cite this URL:|
Chinawa J M, Obu H A, Eke C B, Eze J C. Pattern and clinical profile of children with complex cardiac anomaly at University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu State, Nigeria. Niger J Clin Pract [serial online] 2013 [cited 2019 Dec 15];16:462-7. Available from: http://www.njcponline.com/text.asp?2013/16/4/462/116890
| Introduction|| |
Congenital heart disease (CHD) is defined as structural abnormality of heart or blood vessels near the heart present either at the time of birth or detected later on.  The incidence of these defects is 0.5-0.8 live birth; it increases to 2-6% if first degree relative is affected.  Complex heart disease is a set of associated malformations involving parts that are necessary for maintenance of the patient's life, each of them being classified as follows: Total anomalous pulmonary venous drainage, hypoplastic left heart syndrome, single ventricle, mitral atresia, pulmonary atresia with intact ventricular septum, tricuspid atresia, double right ventricular outflow tract, double left ventricular outflow tract, tetralogy of fallot (TOF), truncus arteriosus, and transposition of the great vessels.  The incidence of complex forms (moderate and severe forms of CHD) is about 6/1,000 live births.  In 2000, it was estimated that there were 320,000 children with simple conditions, 165,000 with moderately complex conditions, and 138,000 with highly complex conditions, with a total of 623,000. 
Most of the known causes of CHD are sporadic genetic changes, either focal mutations or deletion or addition of segments of DNA.  The genes regulating the complex developmental sequence have only been partly elucidated. Some genes are associated with specific defects. The most common deletion which has extensive symptoms including defects of the cardiac outflow tract including TOF.  Known antenatal environmental factors include maternal infections (Rubella), drugs (alcohol, hydantoin, lithium, and thalidomide), and maternal illness (diabetes mellitus, phenylketonuria, and systemic lupus erythematosus). 
A congenital heart defect (CHD) is a heart problem which is present at birth and is caused by improper development of the heart during fetal development. In the majority of the instances, when a baby is born with CHD, there is no known reason for the heart to have formed improperly. Scientists know that some types of congenital heart defects can be related to an abnormality of an infant's chromosomes (5-6%), single gene defects (3-5%), or environmental factors (2%). In 85-90% of cases, there is no identifiable cause for the heart defect, and they are generally considered to be caused by multifactorial inheritance.  Consanguineous marriages have been noted as an important factor contributing to increase in complex cardiac malformations.  This is influenced by the degree of relatedness between the spouses i.e., first cousins, double first cousins, and second cousins. A consistent positive association has been reported between consanguinity and VSD and atrial septal defects, pulmonary atresia, (TOF) and other CHDs. ,,, Consanguinity, however, is not a common practice among the Igbos who are the indigenous and predominant inhabitants of Enugu and environs but is occasionally noted among Hausa-Fulani extraction who migrated to this area with their cattle for grazing.
Three complex congenital malformations commonly reported are TOF, transposition of the great arteries, and single-ventricle physiology =  There are also others that are either classified as moderate or severe in complexity. These are double outlet ventricle, cor triatriatum sinistrum, and dextrum etc.
Congenital complex cardiac abnormality plays a major role in morbidity and mortality of children.  However, the treatment and rehabilitation of these children with congenital abnormality is very costly; hence, the need to identify causative and risk factors and prevent them early,  where possible. The birth of an infant with major malformations whether diagnosed ante-natally or not evokes an emotional parental response.  Parents are likely to feel anxious and guilt on learning of the existence of a congenital complex cardiac anomaly and require sensitive counseling. 
Prevalent studies of congenital complex anomalies are useful to establish baseline rates, to document changes over time and to identify clues to etiology. They are also important for health services planning and evaluating antenatal screening in populations with high risk. The study is also important as it may help to raise the awareness and make a case for both pediatric cardiac surgery and interventional cardiology. It will also emphasize the loss of babies with congenital complex cardiac abnormalities.
We are not aware of any study of this nature from Enugu or southeast Nigeria in general. In addition, the University of Nigeria Teaching Hospital (UNTH) moved to its permanent site at Ituku-Ozalla 4 years ago, and since then no work has been done on the prevalence and pattern of presentation of complex cardiac anomaly in children in the area. This study was thus designed to bridge this gap with a view to determining the prevalence of complex cardiac anomaly among children attending UNTH, Ituku-Ozalla, and the different types of abnormalities that are prevalent. It is hoped that this will add to the body of knowledge available on these disorders and may stimulate further research in the area on the subject.
| Materials and Methods|| |
The aims and objectives of this study were to determine the prevalence of congenital complex cardiac abnormalities among children attending the children outpatient clinic of the UNTH, Ituku-Ozalla, Enugu State; to describe the different forms of abnormalities seen among these children; to determine the various clinical profile, and outcome of congenital complex cardiac abnormality at UNTH.
Purposes of this study, congenital complex cardiac abnormalities are defined as obvious abnormality of structure or form which is present at birth or noticed within a few days after birth involving two or more heart lesions.
The study was conducted at the children outpatient clinic of the UNTH, Ituku-Ozalla, Enugu, Nigeria. The hospital was then located at her temporary site within the city (Enugu) center. In January 2007, the hospital was re-located to its permanent site at Ituku-Ozalla, about 22 km away from Enugu metropolis.
The hospital provides care for children and also receives referrals from different parts of Enugu, the rest of Enugu State and surrounding states. Enugu State of Nigeria has a population of about 3.3 million people according to the national census of 2006; the surrounding states of Abia, Anambra, Benue, Ebonyi, Delta, Imo, and Kogi have populations ranging from 2.2 to 4.2 million people.
Facilities for genetic testing are not available in our center and are thus not offered to babies treated in the unit.
A cross-sectional retrospective study in which a review of the records of all children attending UNTH over a 5-year period (January 2007 and April 2011) was undertaken. The folders (case files) of these children were retrieved from the hospital records department and examined individually by the investigators. Data collection was done with structured forms designed for the study. The diagnosis of congenital complex cardiac abnormality was based on clinical evaluation and 2-D echocardiogram examination (as documented by doctors in the patients' folders). Patient's history, including antenatal history, history of exposure to teratogens, and family history of consanguinity were obtained from these folders. Further information obtained included maternal age and type of congenital complex cardiac abnormality. The prevalence rate was estimated as a percent of the total number of children attending children outpatient within the period of the study (Number of children with congenital complex cardiac abnormalities/total number of children admitted in the hospital for the duration of study).
Data were analyzed using SPSS 13. Rates and proportions were calculated with 95% confidence intervals (CI). The proportions were compared using students t-test. Level of significance was set at P < 0.05.
Ethical approval for this study was sought from the Ethics and Research Committee of UNTH.
| Results|| |
A total of 31,795 children attended the children outpatient clinic of the hospital over the study period, of these, 65 had cardiac diseases, from which 16 were found to have congenital complex cardiac abnormalities of various types, giving a prevalence of 0.05% [Table 1]. Age group ranged from 6 months to 10 years.More than 80% of children presented between the 1 st and 6 th year of life [Table 1].
Out of the 16 cases 14 (87.5%) were male and 2 (12.5%) female. Male to female ratio was 7:1. The commonest complex cardiac lesion was TOF 6 (37.5%) [Table 2], the mean age of presentation was 11.5 months.
[Table 2] shows the types of congenital abnormality seen in these children. TOF is the commonest complex cardiac anomaly 6 (37.5%).
Cyanosis 9 (56.3%), finger clubbing 9 (56.3%), failure to thrive 5 (FTT) (31.3%), breathlessness, and easy tiredness 4 (25.0%) occurred mostly among children with congenital complex heart disease [Table 3].
[Table 4] shows that complex cardiac anomaly is commonly found in males than females in the ratio of 7:1.
[Table 5] shows the outcome and history of consanguinity among children with complex cardiac anomaly. Two children were referred for surgery abroad and these were inoperable, others are been followed up and could not be referred due to financial reasons. There was no history of consanguinity in any of our patient.
|Table 5: Outcome and history of consanguinity (HS) of complex congenital heart defects |
Click here to view
| Discussion|| |
CHDs are among the more common major malformations at birth.  In developing countries thousands of children die due to CHD. One-quarter of all deaths from CHD occur in the 1 st month of life, and half to two-third of deaths occur within 1 st 7-10 days of life.  Many infants require corrective or palliative surgery and frequent hospitalization during 1 st year of life.
Alfred Blalock, in 1945, performed the first surgical connection of the left subclavian artery to the ipsilateral pulmonary artery in cyanotic patient with pulmonary stenosis or atresia.  This was the start of classical Blalock-Taussig shunt creation. Richard Brock carried out the first pulmonary valvulotomy using a closed technique.
The main achievements of the 1950s were the repair of ventricular septal defect (VSD) and TOF. ,[ 15] In the 1960s, atrial physiological correction of transposition of the great vessels (TGV) and the interposition of conduits between the right ventricle and pulmonary artery was done and in the 1970s, the techniques of Fontan and Jatene for the reconstruction of single-ventricle heart and TGV respectively were first initiated. ,,,
The prevalence of congenital complex cardiac abnormalities of 0.05% obtained in this study is similar to that in one study.  Other studies reported 2.5, 5.2, and 6.4% respectively as prevalence rates. , The reason for this varying prevalence could be due to the fact that they are hospital study and as such, geographical differences may count. The prevalence rate of 0.05% obtained in this study appears lower when compared to the general population. This low value could be due to the fact that it is a hospital based study. A good number of these children do not present to the teaching or specialist hospitals but are seen at other peripheral hospitals and as such this work may not be able to "capture" these other children. Some that are born outside the hospital with congenital abnormalities are not taken to hospitals for care but are taken to traditional healers or other alternative practitioners while some are just left at home to their fate. Some that are brought to peripheral hospitals may not be referred to tertiary or teaching hospitals for care because of the current low level of activity at the national cardiac centre at UNTH. Needless to mention that majority of these children are not well managed and a good number die or are left with avoidable complications.
However, many studies gave account of prevalences of each complex cardiac anomaly. For instance, TOF is the most common cyanotic congenital heart defect.≠  Tetralogy of Fallot occurs in approximately 400 per million live births.  On the other hand, in Malta, the birth prevalence for TOF between 1980 and 1994 was 0.64 per 1000 live births, prompting speculation of a genetic predisposition toward the condition.  In the same vein, a single ventriclewhich is defined as a heart with one ventricle receiving inflow from two separate atrioventricular valves or a common atrioventricular valve accounts for about 1% of all cardiac anomalies with an incidence of about 0.05-0.1 per 10,000 live births with a prevalence of between 0.0005 and 0.001%.  On the other hand, cor triatriatum, a rare anomaly is reported to have a prevalence rate of about 0.1% of cases of CHD. These isolated prevalences of teratology of Fallot and single ventricle are similar to our study which is 0.018 and 0.003%, respectively. The observed similarities in prevalences with studies that looked at populations not similar to ours could be due to the fact that both studies were done in a referral institution were major congenital complex cardiac defects are been admitted.
Clinical profile of complex cardiac anomaly depends on the very type, but in general, cyanosis, breathlessness, and early presentation is the key note.  Most of our series presented with cyanosis and breathlessness.
Associations of complex cardiac anomaly with syndromes cannot be overemphasized. For instance, single ventricle could be associated with tricuspid atresia (TA), hypoplastic left heart syndrome (HLHS), mitral valve atresia (usually associated with HLHS), single left ventricle, double outlet right ventricle (DORV), and pulmonary atresia with intact ventricular septum (PA/IVS).  In our study, single ventricles are associated with more than one of the above.
It is important to note that VACTERAL Associations and talipe deformities were seen among two children in our study. VACTERAL Associations and talipe deformity have been reported in some children with complex cardiac anomaly by some workers., Martinez-Frias et al., in their work noted TOF as the most common complex congenital heart defects seen in the VACTERAL association. Less common defects in the association such as truncus arteriosus, and transposition of the great arteries were also reported.
In our study, majority of our children with complex CHD were between the age of 1 and 12 years. It is noted that most of these patients presented after the 1 st year of life. These findings are in accordance with other studies. , The reason why more males are affected could be that in Nigeria, more attention and health seeking behavior are given more to male children. Other possible reasons for the male preponderance could be that XY karyotype may confer protection in this case causing the males to survive longer than the females thus making the males more available for studies than the female.
The main focus of investigation is 2-D echocardiography and ECG. Although cross-sectional echocardiography with Doppler has been shown to be of great value in diagnosis of patients with cor triatriatum, biplanar trans esophageal echocardiogram (TEE) provides a more complete and detailed data of the anatomy of cor triatriatum and other complex cardiac anomaly.  In this series, 2-D echocardiography, ECG and chest radiographs were used for the diagnosis of complex cardiac anomaly.
Prenatal diagnosis may help detect this anomaly early and avert numerous morbidity and mortality that follow this disease. Prenatal diagnosis has not yet gained ground in the management of complex cardiac disease in Nigeria. However, prenatal diagnosis of a major cardiac abnormality tends to precipitate a crisis for the affected parents. In a setting of grief and emotional distress, there is the challenge to provide meaningful information of the abnormality, its need for intervention and likely outcome, so as to enable the parents, if allowed the option, to come to a fully informed decision as to whether to continue with the pregnancy. 
In developed countries, early detection and surgical intervention have provided a high chance of survival in children with CHD but in developing countries like ours, the facilities for diagnosis and treatment of children with complex CHD are limited to larger cities and quite expensive and beyond the reach of poor, so many children die before diagnosis at an early age.
To improve the survival of children with complex CHD there is need to diagnose and treat CHD at earliest age by provision of diagnostic and surgical and other interventional facilities at each corner of the country in order to manage successfully. For instance, we have two inoperable cases referred outside the country as a result of late presentation. Others only ended up receiving saline phoresis and drugs and had been in the waiting list of surgery abroad for years because of financial constraint. The situation may not change until the challenges reported by Eze and Ezemba  in an earlier work at UNTH are addressed. Something is being done in that direction locally but the Federal Ministry of Health needs to do more.
A retrospective, cross-sectional study of this nature is bound to be faced with a number of challenges, and expectedly so as the investigators are not in complete control of fully "in-charge" of the processes. Firstly, retrieving patients' folders from the hospital records department (which is yet to be fully computerized) was a rather Herculean task. Some of the retrieved folders contained inadequate information and this affected the quality of the study. In addition, a hospital-based study of this nature, especially one restricted to only a section of the hospital as is the case in this instance, cannot be said to reflect truly what obtains in the general population. A prospective, community-based study is thus desirable.
| Conclusions|| |
The results of this study show that 0.05% of children admitted to cardiology clinic of a teaching hospital in Enugu state had congenital complex cardiac abnormalities and that the commonest forms seen were those with cor triatriatum and TOF. The prevalence rate obtained in this study, however, may not reflect the true situation in the general population for reasons adduced in the discussion above but gives a clue to the existence of the problem and could serve as a stimulus for further studies on the subject. Centers that provide comprehensive care for these patients receive more patients that do affect the statistical data.
| Acknowledgment|| |
We acknowledge the Almighty God whose assistance and ideas through the course of this work were priceless. We are also grateful to all the doctors and nurses that work at the children outpatient clinic for their co-operation. Our gratitude is equally extended to all the staff of the Health Information Technology Department of the UNTH for their support and co-operation.
| References|| |
|1.||Hoffman JI. Congenital heart disease: Incidence and inheritance. Pediatr Clin North Am 1990;37:25-43. |
|2.||Bernstein D. Epidemiology and genetic basis of congenital heart disease. In: Behrman RE, Kliegman RM, Jenson HB, editors. Nelson text book of pediatric. 17 th ed. Philadelphia: WB Sunders 2004. p. 1499-1502. |
|3.||Miyague NI, Cardoso SM, Meyer F, Ultramari FT, Araujo FH, Rozkowisk I, et al. Epidemiological study of congenital heart defects in children and adolescents. Analysis of 4,538 cases. Arq Bras Cardiol 2003;80:269-78. |
|4.||Srivastava D. Making or breaking the heart: From lineage determination to morphogenesis. Cell 2006;126:1037-48. |
|5.||Factors contributing to congenital heart disease. Lucile Packard Children's Hospital at Stanford. Available from: http://www.lpch.org/DiseaseHealthInfo/HealthLibrary/cardiac/fcchd.html. [Last accessed on 2012 July 3]. |
|6.||Naderi S. Congenital abnormalities in newborns of consanguineous and non consanguineous parents. Obstet Gynecol 1979;53:195-9. |
|7.||Becker SM, Al Halees Z, Molina C, Paterson RM. Consanguinity and congenital heart disease in Saudi Arabia. Am J Med Genet 2001;99:8-13. |
|8.||Nabulsi MM, Tamim H, Sabbagh M, Obeid MY, Yunis KA, Bitar FF. Parental consanguinity and congenital heart malformations in a developing country. Am J Med Genet A 2003;116:342-7 |
|9.||Yunis K, Mumtaz G, Bitar F, Chamseddine F, Kassar M, Rashkidi J, et al. Consanguineous marriage and congenital heart defects: A case-control study in the neonatal period. Am J Med Genet A 2006;140:1524-30. |
|10.||Chehab G, Chedid P, Saliba Z, Bouvagnet P. Congenital cardiac disease and inbreeding: Specific defects escape higher risk due to parental consanguinity. Cardiol Young 2007;17:414-22. |
|11.||Williams RG, Pearson GD, Barst RJ, Child JS, Del Nido P, Gersony WM, et al. Report of the National Heart, Lung, and Blood Institute Working Group on research in adult congenital heart disease. J Am Coll Cardiol 2006;47:701-7. |
|12.||Keith JD. Prevalence, incidence and epidemiology. In: Keith JD, Rowe RD, Vlad P editors. Heart disease in infancy and childhood, 3 rd ed. NewYork: Macmillan; 1978. p. 3. |
|13.||Levin AR. Management of the cyanotic newborn. Pediatr Ann 1981;10:16-27. |
|14.||Henry T. Bahnson. Surgical treatment of pulmonary stenosis: A Retrospection. Ann Thorac Surg 1982;33:96-98 |
|15.||Kirklin JW, Payne WS, Theye RA, DuShane JW. Factors affecting survival after open operation for tetralogy of Fallot. Ann Surg 1960;152:485-93. |
|16.||Mustard WT. Successful two-stage correction of transposition of the great vessels. Surgery 1964;55:469-72. |
|17.||Rastelli GC, Titus JL, McGoon DC. Homograft of ascending aorta and aortic valve as a right ventricular outflow. An experimental approach to the repair of truncus arteriosus. Arch Surg 1967;95:698-708. |
|18.||Fontan F, Baudet E. Surgical repair of tricuspid atresia. Thorax1971;26:240-8. |
|19.||Jatene AD, Fontes VF, Paulista PP, Souza LC, Neger F, Galantier M, et al. Anatomic correction of transposition of the great vessels. J Thorac Cardiovasc Surg 1976;72:364-70. |
|20.||Yasmeen M, Rehana M, Feroz M. Pattern of congenital heart disease at Liaquat University Hospital Hyderbad. Pakistan Heart Journal 2007;40:1-2. |
|21.||Ferencz C, Rubin JD, McCarter RJ, Brenner JI, Neill CA, Perry LW, et al. Congenital heart disease: Prevalence at livebirth. The Baltimore-Washington Infant Study. Am J Epidemiol 1985;121:31-6. |
|22.||Child JS. "Fallot's tetralogy and pregnancy: prognostication and prophesy". J Am Coll Cardiol 2004; 44: 181-3. |
|23.||Petrini J, Damus K, Russell R, Poschman K, Davidoff MJ, Mattison D. Contribution of birth defects to infant mortality in the United States. Teratology 2002;66(Suppl 1):S3-6. |
|24.||Porter I, Vacek J. Single ventricle with persistent truncus arteriosus as two rare entities in an adult patient: A case report. J Med Case Rep 2008;2:184. |
|25.||Gheissari A, Malm JR, Bowman FO Jr, Bierman FZ. Cor triatriatum sinistrum: One institution's 28-year experience. Pediatr Cardiol 1992;13:85-8. |
|26.||Attenhofer Jost CH, Connolly HM, Danielson GK, Dearani JA, Warnes CA, Jamil Tajik A. Clinical features and surgical outcome in 25 patients with fenestrations of the coronary sinus. Cardiol Young 2007;17:592-600. |
|27.||Martinez-Frias ML. Approaches to the analysis of infants with multiple congenital anomalies. Am J Med Genet 2001;101:33-5. |
|28.||McLean MK, Kung GC, Polimenakos A, Wells WJ, Reemtsen BL. Cor triatriatum associated with ASD and common atrium in 7-month-old with tachypnea and failure to thrive. Ann Thorac Surg 2008;86:1999. |
|29.||Menahem S, Grimwade J. Pre-natal counselling: Helping couples make decisions following the diagnosis of severe heart disease. Early Hum Dev 2005;81:601-7. |
|30.||Eze JC, Ezemba N. Open-heart surgery in Nigeria: Indications and challenges. Tex Heart Inst J 2007;34:8-10. |
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]
|This article has been cited by|
||Challenges of Caring for Functionally Single Ventricle Patients in Africa
| ||Frank Edwin,Mohamed-Adel Elgamal,Abid Dorra,Darshan Reddy,Kow Entsua-Mensah,Innocent Adzamli,Nana-Akyaa Yao,Mark Tettey,Martin Tamatey,Susan Vosloo,Rob Kinsley |
| ||World Journal for Pediatric and Congenital Heart Surgery. 2019; 10(3): 338 |
|[Pubmed] | [DOI]|
||Cardiovascular disease in Africa: epidemiological profile and challenges
| ||Ashley K. Keates,Ana O. Mocumbi,Mpiko Ntsekhe,Karen Sliwa,Simon Stewart |
| ||Nature Reviews Cardiology. 2017; |
|[Pubmed] | [DOI]|
||Association between polymorphisms in IL27 and risk for CHD in a Chinese population
| ||Danyan Zhang,Mingfu Ma,Yuyou Yang,Ling Wan,Zhixi Yang,Jing Lv,Xinsheng Li,Hao Yang,Pei Huang,Lianbing Li |
| ||Cardiology in the Young. 2015; : 1 |
|[Pubmed] | [DOI]|
||Children With Tetralogy of Fallot in an Urban Centre in Africa
| ||Barakat Adeola Animasahun,Akpoembele Deborah Madise-Wobo,Samuel I Omokhodion,Olisamedua Fidelis Njokanma |
| ||Journal of Cardiovascular and Thoracic Research. 2015; 7(4): 168 |
|[Pubmed] | [DOI]|
||Association between polymorphisms inAXIN1gene and atrial septal defect
| ||Yan Pu,Peng Chen,Bin Zhou,Yanyun Wang,Yaping Song,Ying Peng,Li Rao,Lin Zhang |
| ||Biomarkers. 2014; : 1 |
|[Pubmed] | [DOI]|