The frequency of congenital heart diseases among premature neonates

La frecuencia de las cardiopatías congénitas entre los recién nacidos prematuros

Esta obra está bajo una Licencia Creative Commons Atribución-SinDerivar 4.0 Internacional.

Congenital heart disease (CHD) is one of the most common congenital defects and accounts for nearly one-third of all major congenital anomalies¹. Some population- based epidemiological studies on CHD have indicated a prevalence ranging from 4 to 50 per 1,000 live births^2,3 nd the incidence is even higher in cases of premature children, stillbirth or spontaneous abortion. CHD in children continues to be an important cause of death⁵, and constitutes a potential risk of sudden cardiac death in adulthood even with mild cardiac lesion⁶. The character of the heart sounds and the presence and character of any murmurs further narrow the differential diagnosis. The final diagnosis is then confirmed by echocardiography, CT or MRI, or cardiac catheterization⁷.

Acyanotic congenital heart disease includes left-to-right shunts resulting in an increase in pulmonary blood flow (patent ductus arteriosus [PDA], ventricular septal defect [VSD], atrial septal defect [ASD]) and obstructive lesions (aortic stenosis, pulmonary stenosis, coarctation of the aorta), which usually have normal pulmonary blood flow⁸.

Cyanotic congenital heart disease occurs if there is right-to-left shunt, Cyanosis, occurs when approximately 5 g/100 mL of reduced hemoglobin is present in systemic blood. The most common cyanotic defects are the five Ts: Tetralogy of Fallot Transposition of the great arteries, Tricuspid atresia. Truncus arteriosus, Total anomalous pulmonary venous return⁸, severe types of congenital heart problems are often detected while the baby is still in the womb or within the first few weeks of life⁹.

Fetal echocardiogram (during pregnancy): This test shows moving pictures of a baby’s heart and how it is working as early as 16-18 weeks into pregnancy. It is usually used if congenital heart disease runs in your family, or if there are other factors that make a heart problem more likely¹⁰.

our child’s heart team should talk with you about treatment options and what to expect. Treatment may include a combination of (Medications, Cardiac catheterization, Devices that are placed or implanted in the heart)^11.

Aim of the study

to study the frequency of congenital heart diseases in premature neonates.

250 neonates were randomly enrolled in the study who were admitted to the pediatric ward in AL-Emamain AL-Khadhumain Medical city. The neonates were examined during the period from 15^th of November, 2018 to ^7th of January 2019, the neonates with suspicion of congenital heart disease were sent for Echocardiography, after completing data collection, (name, gender, gestational age, type of C.H.D., maternal exposure to drugs e.g. anticonvulsant, antibiotics) neonates with PDA were excluded from the study. The result calculated by using SSPS program of statistics version 13 and P value is significant if was less than 0.05 2.3

From the total 250 neonates only 11 (4.4%) having cardiac defect. As seen in table-1.

Table 1
The percentage and frequency of cardiac defect among the neonates.

Among the neonates who have cardiac defect that 8 (72.7%) of them have ASD, 2 (18.2%) of them have VSD, and 1 (9.1%) of them have TOF, as seen in table-2

Table 2.
The percentage and frequency of cardiac defect

The most common gestational age was between 31-32 week seen in 5 (45.6%) neonates , as in table-3.

Table 3.
percentage of cardiac defect according to gestational age.

the relationship between the type of CHD and the gender, the male to female ratio was 1.7: 1, as seen in table-4.

Table 4
Type Of CHD (a cyanotic or cyanotic) according to Gender

We found that 6(54%) of neonates their mothers had taken drugs during pregnancy and P value = (0.073) which is not significant. As seen in table-5

Table 5.
The relation between drugs taken by mothers & occurrence of CHD.

The most common cardiac defect noticed in neonates whose mother taken drugs, was a cyanotic CHD 5(45%) than cyanotic type, as seen in table-6

Table 6.
type of CHD according to exposure to drugs

No death recorded among neonates included in the study.

Prevalence of CHDs 4.4% was significantly higher than the reported birth prevalence of CHDs in term neonates 0.6 – 1% (6-10/1000 births)^12,13. Importantly, the subset of severe CHDs were almost five-fold more likely in very/extremely premature neonates when compared with term neonates. and 7.4/1000 birth hospitalizations in pre term infants in other study¹⁵, the current study found that the most frequent cardiac defect is ASD 72.2 % and least frequent is TOF 9.1% and this correlate with the other studies¹⁵. And this indicate that a cyanotic CHD are more common that the cyanotic, regarding the frequency of CHD according to the gestational age (45.6% at 31-32 weeks, 27.2% at 25-28 weeks and 27.2% at 29-30 weeks GA). These data highlight the substantial differences that small increments of prematurity can have on outcomes in neonates with CHD, and may influence future decisions surrounding surgical interventions, medical management, and palliative care¹⁵.

The relation between the gender and type of CHD, we found that the male was more than female, which was the same results as in the other studies¹⁵. Also we try if a specific gender is related to a specific type of CHD and it was not significant (p-value = 0.073).

The effect of embryonic exposure to maternal drugs during cardio genesis, and the evidence suggests that maternal use of ethanol, anticonvulsants, lithium, and exogenous female hormones may increase the risk of congenital heart disease, the evidence indicates that the vast majority of heart malformations cannot be attributed to these pharmacologic agents, and this result was the same result that obtained by another research¹⁶.

The mortality rate of our study was 0%, and it was the same result to the research¹⁵, reports suggesting that larger ASDs actually exacerbate underlying chronic lung disease of prematurity^17,18.

The frequency was about 4.4% and a cyanotic congenital heart disease were more common than cyanotic, and the embryonic exposure to maternal drugs can be a risk factor to CHD in a

premature neonates, and also the frequency of congenital heart disease were higher in males than female.

Recommendations

It is worthy to postpone premature delivery as possible as can, there is a great need for further and larger studies to assess the incidence, follow up and long term outcome of neonates with CHD.

Patients’ consent

Informed written consent was taken from the parents of the children to participate in this study and for publication of the clinical details.

Grant information The authors declared that no grants were involved in supporting this work.

Conflicts of interest The authors have no conflict of interest to declare.