Pattern of Congenital Heart Disease A Hospital-Based Study *Sadiq Mohammed Al-Hamash MBChB, FICMS

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1 Pattern of Congenital Heart Disease A Hospital-Based Study *Sadiq Mohammed Al-Hamash MBChB, FICMS ABSTRACT Background: The congenital heart disease occurs in 0,8% of live births and they have a wide spectrum of severity and about 30-40% of patients with congenital heart disease are symptomatic during the 1 st year of life, and these disease still one of the frequent cause of morbidity and hospital admission among the pediatric age group. Objective: This study was carried out to identify the specific types of CHD, sex and age distribution and the most common pattern of presentation among hospitalized patients. Methods: This is a retrospective study of 89 patients with congenital heart disease admitted to the fifth unit in Child Welfare Hospital in Baghdad from January 2003 to January The diagnosis was established by two dimensional and Doppler echocardiography examination. The pattern of congenital heart disease, mode of presentation, male to female incidence, and the effect of different lesions on the growth parameters had been studied. Results: Out of 1023 patients, 89 patients 8.6% had congenital heart disease. The most common congenital heart disease were ventricular septal defect 51.8%, Tetralogy of Fallot 17.9%, Patent ductus arteriosus (13.5%), Transposition of great arteries 8.9%, Pulmonary stenosis 4.4%, and Atrial septal defect 3.4%. The most common presentation was respiratory infection and heart failure in a cyanotic patients and cyanosis in cyanotic groups. Conclusion: Patent ductus arteriosus and atrial septal defect defects were more common in female while all other lesions had equal male to female incidence or slightly more common in male. Key Words: Congenital heart disease; hospital based-study. Al-Kindy Col Med J 2006; Vol.3 (1): P Introduction Congenital heart diseases occur in % of live births. The incidence is higher in stillborns 3-4%, abortuses10-25%, and premature infants' about 2%, excluding patent ductus arteriosus PDA (1). Congenital cardiac defects have a wide spectrum of severity in infants. About 30-40% of patients with congenital cardiac defects are symptomatic in the 1 st year of life, while the diagnosis can be established in 60% of patients by the 1 st month of age. There are 8 common congenital heart lesions VSD, ASD, PDA, coarctation of aorta, TOF, TGA, PS and AS, all together make up to 90% of all cases. The remaining 10% consists of more complex anomalies (2). Although the advent in the diagnostic techniques (especially the color Doppler echocardiography), VSD is still considered as the commonest lesion and constitutes about 25-30% of all CHD while ASD, PDA and coarctation are considered the next most common congenital heart diseases and each lesion forms about 8-10% of all congenital heart diseases. Tetralogy of Fallot is the most common cyanotic congenital heart disease accounts for 6-8% of the whole CHD and TGA for 5-6% of these diseases (3). Different Types of CHD: 1. Acyanotic Heart Disease The most common lesions in acyanotic congenital heart disease that cause left to right shunting and volume overload are: VSD, ASD and PDA. The direction and magnitude of the shunt across such a communication depends on the size of the defect and relative systemic and large lesions such as large VSD may be associated with little shunting and few symptoms during the initial weeks of life and when pulmonary vascular resistance decline over the next several weeks, the volume of the left-to-right shunt increases. If the hole is small the shunt may be trivial, but if it is large it may represent the majority of cardiac output. So the blood flow through the pulmonary artery may be several times greater than that through the aorta and this results in signs and symptoms of heart failure and failure to thrive begins to appear (1,3), so most patients with CHD and significant left to right shunt have poor weight gain (4). 2- Cyanotic Heart Disease Some of infant and children with congenital heart disease are centrally cyanosed because the unsaturated blood bypasses the lungs. Cyanotic heart disease can be subdivided into two types. The first type, the lungs are under-perfused as blood shunts from right to left bypassing the lungs, TOF is the commonest example, the essential features in TOF, being the commonest cyanotic CHD, are a large VSD and stenosis of the right ventricular outflow tract. There is resistance to the flow of blood through the pulmonary valve with a consequent shunt of Al-Kindy Col Med J 2006; Vol.3 (1) 44 Original Article

2 blood from the right to left ventricle and thence to the aorta. So the degree of cyanosis depends on the degree of obstruction to pulmonary blood flow. The newborn with this lesion and mild degree of obstruction usually pink and cyanosis develops and increases over the next few weeks or months while if the obstruction is severe, the cyanosis may be present during the neonatal period. Hyper cyanotic spells may be particular problem during the first 2 years. Heart failure is extremely rare in TOF (1, 2), so poor weight gain is seldom a problem in such patients (5). In the second type, the lungs are normally filled or even over-perfused with blood, but cyanosis results as there is inadequate mixing of both the systemic and the pulmonary circulations, transposition of the great arteries is the commonest example. In patients with transposition of great arteries, which is the most common cause of cyanosis during the neonatal period, progressive cyanosis within the first few hours or days of life and the affected baby becomes increasingly blue and without treatment, this disease has lethal course (1, 2) and few patients survive the first year of life Methods In this retrospective study, the case record of all patients with CHD admitted to 5 th unit in Welfare Teaching Hospital from January 2003 to January In each patient, the following data had been collected: age, sex, cause of admission, and the growth parameter as height and weight. The diagnosis of CHD was done by electrocardiography, chest X-ray and by M- Mode, two dimensional echocardiography and Doppler studies. The echocardiography studies were performed with a mechanical sector scanner at 3 & 5 MHz. Patients were studied in the supine or left lateral 30 o decubitus position to obtain different views. Neither catheterization nor surgical interventions were done to any patients. Results The age of the patient ranged from 10 days to 18 months. Among the 89 studied patients, there were 46 patients 51.8% with VSD, 16 patients 17.9% diagnosed as TOF and 12 patients 13.5% showed to have patent duct arteriosus, 8 patients 8.9% had TGA, 4 patients 4.5% had pulmonary stenosis, the least common congenital heart disease was the atrial septal defect diagnosed in 3 patients 3.4% only, Table -1, Figure -1. The study of sex distribution among different CHD showed that PDA and ASD were more common in female while other lesions of congenital heart disease had equal male to female, or slightly more common in male incidence,table-2. The study of the time of presentation of CDH revealed that 66 patients 74% presented in the 1 st 6 months of life while 19 patients 21.6% presented in the 2 nd six month of the life and only 4 patients 4.4% were diagnosed after the 1 st year of life, Table- 3, Figure-2. The study of mode of presentation of CHD showed the most common presentation of patients with acyanotic lesion was chest infection, 46 patients 70.7 %, heart failure, 40 patients 21.6% while in patients with cyanotic lesions, cyanosis was the most common presenting cause in 22 patients 91.7% and no patient presented with heart failure Table -4, 5. Chest infection was considered the cause of admission in 70.7% in acyanotic patient in comparison with 8.3% among the cyanotic group (p: ) which is highly significant, while the cyanosis is more common as a cause of admission in cyanotic patients 91.7% than acyanotic patients 7.7%, and this difference is statically significant (p: ). In this study, we assessed the effect of different types of congenital heart disease on the weight of the patients, and we found that the acyanotic types of CHD (ASD, PDA, PS and VSD) had more deleterious effect on the weight of the patients than that caused by cyanotic heart disease as in Table -6, 7. In acyanotic CHD the weight of 68.75% of the patients were below 3 rd centile, while only a 33.3% in cyanotic group (p: 0.002). Discussion The incidence of CHD can not be determined in this study as it is a hospital based rather than a community based study, but the incidence of CHD among the higher than Al-Ani study (6) where he reported incidence of 5.16%, this is because our hospital receives referred cases from other hospitals in Baghdad and from other governorates of Iraq, in addition to the general increase in the orientation about the congenital heart disease in Iraq in the last few years. The relative incidence of the various abnormalities found in this study is compared with other studies, Table-8.This study proved that VSD is the commonest congenital heart disease both in community and hospital based studies, but our result is higher than that recorded by Walloopillai study (7), and nearly comparable with Chadha from India (8) and Al-Jumaily study (9), where they reported46%-49.7% respectively.

3 (Table 1) Pattern and Frequency of (Figure 1) Pattern and Frequency of CHD Congenital Heart Disease CHD Diagnosis Total no. % VSD % TOF % PDA % TGA 8 8.9% Diagnosis M:F VSD 1.1:1 TOF 1.6:1 PDA 0.6:1 TGA 1.6:1 PS 1:1 (Table 2) The Sex Distribution among various Types of CHD VSD TOF PDA TGA PS ASD (Table 3) Age Distribution at Diagnosis in Different Types of CHD Diagnosis 0-6 M 6-12 M > 12 M Total VSD TOF PDA TGA PS ASD Total (Figure 2) Age Distribution at Diagnosis in Different Types of CHD 6-12 M; 21.60% > 12 M; 4.40% 0-6 M; 74% (Table 4) Presentation of Acyanotic CHD Diagnosis Chest Infection Cyanosis Heart Failure Total VSD PDA PS ASD Total (%) 46 (70.7) 5 (7.7) 14 (21.6) 65 (100)

4 (Table 5) Presentation of Cyanotic CHD Diagnosis Chest Infection Cyanosis Heart Failure Total TOF TGA Total (%) 2 (8.3%) 22 (91.7%) - 24 (100%) (Table6) The Weight Centile of Patient with Acyanotic CHD Acyanotic CHD Wt <3 rd centile Wt >3 rd centile Total VSD 33 (70.7%) 13 (29.3%) 46 ASD 3 (100%) - 3 PDA 7 (58.3%) 5 (41.7%) 12 PS 2 (50%) 2 (50%) 4 Total 44 (68.75%) 20 (31.25%) 64 (Table7) The Weight Centile of Patient with Cyanotic Chd Cyanotic CHD Wt < 3 rd centile Wt > 3 rd centile Total TOF 3 (18.7%) 13 (81.3%) 16 TGA 5 (62.5%) 3 (37.5%) 8 Total 8 (33.3%) 16 (66.7%) 24 Table (8): Incidence of Various Lesions of CHD in other Studies Lesions VSD TOF PDA TGA ASD & AV canal PS Al-Ani, Al-Ramadi 1994 (6) Walloopillai, Ceylon 1970 (7) Indian, Delhi, 2001 (8) Al-Jumaily, Baghdad 991 (9) Hoffman, USA 1978 (10) This study, Baghdad VSD is the commonest congenital heart disease both in community and hospital based studies, but our result is higher than that recorded by Walloopillai study (7), but it is nearly comparable with Chadha from India (8) and Al-Jumaily study (9),where they reported46%-49.7% respectively. Tetralogy of Fallot (TOF) was the second most congenital lesions (18.1%) in our study and this relatively agreed with Hoffman s study (10) and the Iraqi studies (6, 9), but double its incidence in Walloopia study in Ceylon (7). PDA showed to be the third most common congenital lesions and the second most common acyanotic lesions, and this is compatible with Chadha study (8) but higher than that recorded in Al-Jumaily (9) and Walloopillai (7), in Hoffman study (10), he could not detect any patient with PDA and this was due to the recent use of Doppler study by which PDA is easily detected. There is higher incidence of TGA than in other studies (7,10), and this is due to increasing the orientation about the necessity of early referring of such patients to our hospital for proper diagnosis and possible intervention, this explains the youngest age groups included in this study in relation to old age groups in other studies. This study revealed that there was lower incidence of ASD in comparison with other studies, especially community based studies (7,8), where they recorded incidence of 30 and 18%

5 respectively and this proved the fact that ASD is not recorded as significant cause of morbidity in infancy and early childhood. The distribution of incidence of CHD between male and females confirm the old concept that the female patients with PDA and ASD outnumber males (2:1 & 3:1 respectively) while in all the other lesions, there is slight male predominance (1, 2, 6, 7). Regarding the age at which the diagnosis had been done our study indicate that the patients with left to right shunt (VSD & PDA) mostly presented during the first 6 months of life (65%), while the patients with TOF mostly presented in 2 nd 6 months of their age (75%) and only severe cases can present during the 1 st 6 months. All patients who diagnosed as TGA presented within the first few months of life and this compatible with the natural history of this disease (2). In this study, the main cause of presentation of patients with left to right shunt lesions (VSD, PDA & ASD) were chest infection 70.2% and heart failure 23.8% and is explained by excessive pulmonary blood flow which results in heart failure and recurrent pulmonary infection while few patients (5%) can present with cyanosis result from high pulmonary vascular resistance with bidirectional or right to left shunt and this caused by long-standing left to right shunt or in some infants with large VSD or PDA pulmonary arteriolar medial thickness never decrease (1). Cyanosis was the main presenting cause of patients with right to left shunt 91.7% and this is explained by the patho-physiological mechanism of right to left shunt or caused by hyper-cyanotic spells which is the most common complications of patients with TOF. Few patients (8.3%) presented with respiratory infection, and this can result from increase pulmonary blood flow resulted from mild right ventricular outflow tract obstruction. Heart failure which is the most common presenting features of patients with left to right shunts is rare (if ever) in the patients with right to left shunt. The evaluation of growth of our patients revealed that the majority of patients 68.7% with left to right shunt had poor growth state and these results compatible with George W Land study (4) who wrote (this in comparison with non-cyanotic congenital heart disease with significant left to right where most patients with very poor weight gain), while most patients 79.2% with cyanotic congenital heart had good growth status and only minority 33.3% had poor weight gain and this compatible with Thomas PG study (5) who reported that (poor weight gain is seldom a problem in TOF patients). *From the Department of Pediatrics, Al-Kindy College of Medicine, University of Baghdad Address Correspondence to: Dr: Sadiq Mohammed Al-Hamash sadiqjiud@yahoo.com Received 20 th Oct Accepted 19 th May.2005 References 1. Richard E Behrman Vector C Vanghan: Nelson textbook of pediatrics, Disease of the cardiovascular system, 17 th Ed. Saunders comp. 2004; Elliott Anderson RH: Moss Heart disease in infants, children and adolescents, 4th Ed., Baltimore Williams, Wilkins, 1989; David Hull, Derek I, Johnson: Essential pediatrics, 4 th Ed, Churchill Livingstone, 1999; Saad S Al-Ani: Pattern of congenital heart disease in Ramadi Hospital.Al-Anbar UnivJNo11996; Walloopolia NJ: Jausingha MD: Congenital heart disease, incidence and inheritance. Paed Clin North Am, 1990; 37: Chadha Singh N Shukla DK: Epidemiological study of congenital heart disease.indian J Paediatr 2001 Jun; 68(6): Al-Jumaily SA: Pattern of congenital heart disease in Iraqi children, a thesis submitted to Iraqi commission for medical specialization, Hoffman JL Christianson R: Congenital heart disease, in cohort of births with long term follow up. Am J Cardiol, 1978; 42: George W Lund MD: Growth of children with Tetralogy of Fallot: J of Paediatr, 1954; Thomas P Graham MD: Preoperative diagnosis & management of infants with congenital heart disease: The annals of thoracic surg vol.29no.3 Mar Beattie RM : Essential Revision note a pediatrics 1 st Ed Chapter one: 14. Al-Kindy Col Med J 2006; Vol.3 (1) P: 48