Congenital Cyanogenic Heart Disease in Children: About 420 Cases in Africa

Congenital cyanogenic heart disease (CCHD) is a malformation of the heart and large vessels characterized by an oxygen desaturation in the arterial blood, responsible for cyanosis. The general objective was to study the profile of CCHD in Senegalese hospitals. This is a retrospective study carried out over a period of 8 years (January 1, 2010 - December 31, 2017) and including all children aged 0 to 16 years followed for a CCHD. The hospital prevalence was 0.87% for 420 cases collected. The sex ratio was 1.44 and the average age at diagnosis was 16 months. First degree parental consanguinity was noted in 36 cases (30.78%). The main reasons for consultation were breathing difficulty in 242 cases (57.62%) and fever in 136 patients (32.36%). Apart from cyanosis, the clinical signs were dominated by the heart murmur in 313 cases (74.7%), tachycardia in 283 cases (67.38%) and digital hippocratism in 162 cases (38.57%). Cardiomegaly was found in 239 patients (83.36%). The main types of CCHD were tetralogy of Fallot and transposition of the large vessels. In biology, 206 patients (49.05%) presented polyglobulia. A complete surgical cure was carried out in 22 patients (5.24%). Complications were anoxic crisis (52 cases) and hemorrhagic syndrome (17 cases). There were 97 deaths (28.28%) during hospitalization. The diagnosis of CCHD is late in our country and surgical management is poor explaining the high mortality.


Introduction
Congenital cyanogenic heart diseases (CCHD) are malformations of the heart and large vessels characterized by an oxygen desaturation in the arterial blood, responsible for a blue coloration of the mucous membranes and the integuments or cyanosis [1]. Congenital heart diseases (CHD) in general represent the most frequent congenital malformations, in particular 40% of all fetal malformations [2]. The diagnosis of CHD in general has known advances linked to the development of cardiovascular imaging, dominated by echocardiography coupled with color doppler [3]. Today, prenatal diagnosis is possible linked to progress in fetal cardiology through two-dimensional or even three-dimensional fetal echocardiography. This prenatal diagnosis made it possible to reduce the mortality of certain heart diseases by promoting optimal conditions for neonatal care [4] [5].
According to a last study in Senegal, CCHD represents 36.95% of all congenital heart diseases (CHC). Despite considerable advances in diagnosis with the contribution of cardiac ultrasound coupled with color doppler as well as progress in management with the development of pediatric cardiology and cardiovascular surgery, CCHD remains a major public health problem [6]. Studies have been carried out in our country on CHC in general but not specifically on CCHD [7] [8]. Thus, we carried out this work to study the profile of CCHD in Senegalese hospitals.

Methodology
This is a retrospective and descriptive study carried out at the Albert Royer National Children's Hospital (ARNCH) which is a benchmark public hospital for pediatric care in Senegal. It houses a pediatric cardiology department where the majority of children suffering from congenital or acquired heart disease are followed. The study was carried out over an 8-year period from January 1, 2010 to December 31, 2017 and including all children aged 0 to 16 years followed for CCHD confirmed on echocardiography by a pediatric cardiologist. The epidemiological, diagnostic, therapeutic and evolutionary parameters were informed from medical records and hospital registers. The data were entered with the Epi Info version 7 software. The qualitative variables were assessed by determining the numbers, the percentages and highlighting the mode. We did not have an ethical problem.  Table 4 and Table 5.      [12]. The main genetic anomaly was trisomy 21 as described in the literature [13]. The average age at diagnosis was 16 months. This delay in diagnosis is explained by the fact that in our developing countries, the discovery is often made after decompensation due to a lack of diagnostic means and limited access to patient care linked to the low socioeconomic level [10]. The age at diagnosis is later in T4F where the diagnosis is often made in antenatal [14]. The main reasons for consultation were respiratory signs and the main associated pathology was bronchiolitis. Respiratory infections are frequent revealing circumstances [15]. In biology we note a predominance of polyglobulia which is the consequence of hypoxia [16] [17]. This hypoxia was also at the origin of the frequent anoxic crisis in T4F.

During
The number of patients who have undergone surgical treatment remains very low compared to Western countries [17]. This would be linked on the one hand to the high cost of cardiac surgery and on the other hand to an insufficiency of the surgical technical platform. The medical treatment consisted mainly in the prevention of anoxic crises and in the management of associated pathologies.
Surgical repair is indicated in all cases for T4F. The medical and surgical management of TLV and DIRV remains difficult due to their brutal and early revelations [17]. Despite all the actions taken to improve care, there is a considerable gap between the number of children in need of surgical treatment and those who benefit from it. This explains the high mortality in our country. This mortality seems lower in T4F compared to other types of CCHD.

Limits of the Study
The limits of this study are linked to the retrospective nature of our study. These include the presence of several incomplete files, the unavailability of caryotyping.

Conclusion
The diagnosis of CCHD is late in our country and surgical management is poor explaining a high mortality. This is linked to a difficulty in accessing diagnostic means and the limits of the technical platform. Improving the prognosis of CCHD requires the establishment of antenatal diagnosis, extensive neonatal screening for cardiac anomalies; the raising of technical platforms in the pedia-