Surgery of Patent Ductus Arteriosus in Soavinandriana Hospital: Our Experience

Introduction: The missionaries of Doctors of the World began performing the surgical closures of patent ductus arteriosus in Madagascar in 2004. The Malagasy team has been completely autonomous in surgical closures of an isolated patent ductus arteriosus since 2018. The aim of this study was to report on the Malagasy team's experience in the first 5 years of surgical closure of an isolated patent ductus arteriosus at Soavinandriana Hospital. Methods: This was a retrospective and descriptive study, during the five-year period, from January 2018 to December 2022, performed at the Cardiac surgery unit of Soavinandriana Teaching Hospital, including all children underwent surgical closures of an isolated PDA. Demographic data, birth weight, clinical signs, diagnostic imaging, diameter of the ductus, the surgical waiting time after diagnosis, and hospital left stays were analyzed. Results: A total of 104 children underwent surgery of closures of PDA, including 36 boys (34.62%) and 68 girls (65.38%), giving a sex ratio of 52%. The average age was 29.75 months. Fifteen children were born with low birth weight (14.42%). PDA was symptomatic in 84.65% of patients. The commonest symptoms were recurrent pulmonary infections (51.92%) and failure to thrive (25.96%). The mean age at diagnosis was 18 months. Echocardiography showed pulmonary hypertension in 73.25% of cases. The ductus was large in 97.67% of cases, with a mean diameter of 5.17 mm. Chest X-rays showed cardiomegaly (75%) and increased pulmonary vascularization (39.42%). The mean time to surgery after diagnosis was 7.28 months. All patients underwent left posterolateral thoracotomy with sectioning and suturing of the ductus arteriosus. The average hospital stay was 7.33 days. Conclusion: PDA was the most common symptomatic (83.65%) and large (90.38%). Surgical closures of PDA were satisfied in our practice.


I. INTRODUCTION
Patent ductus arteriosus (PDA) is a heart defect in which the ductus does not close within three months of birth.The incidence of PDA in newborns is 1 per 2,000 live births, representing 5-10% of congenital heart disease [1].The incidence of PDA is higher in premature babies, with an increase inversely proportional to the age of pregnancy [2].
In Africa, around 500,000 children are born with congenital heart disease, most of them in sub-Saharan countries [3].PDA is one of the most common congenital heart diseases in African Sub-Saharan countries, ranking second only to ventricular septal defect (19%) in Acyanotic congenital heart disease (15%) [4].Its seriousness lies in the risk of pulmonary hypertension, heart failure, and death.
Since 2004, the missionaries of the Doctors of the World have been performing closure surgery on isolated PDA at Antananarivo's Soavinandriana hospital on a regular 6-month mission.But Malagasy teams have been stand-alone without missionaries in the surgical closure of an isolated patent ductus arteriosus since 2018.Currently, the surgery for the closure of PDA at the Soavinandriana Hospital is funded by the Chain of Hope organization.The number of patients operated on each year depended on the budget provided by the Chain of Hope organization.
The aim of this study was to report on the Malagasy team's experience in the first 5 years of surgical closure of an isolated patent ductus arteriosus at Soavinandriana Hospital.

II. MATERIALS AND METHOD
This was a single center, retrospective, and descriptive study of the first five years (January 2018 to December 2022) of practice on surgical closure of an isolated ductus arteriosus in Malagasy children carried out by the Malagasy team at Soavinandriana Teaching Hospital (Cenhosoa).
Soavinandriana Teaching Hospital is a reference hospital for cardiac surgery in Antananarivo.Surgical closure of isolated PDA is the only surgical procedure for congenital heart disease performed at this hospital.Usually, patients were selected after a consultation carried out by the team in different regions of the island, followed by a confirmatory echocardiogram.Patients with isolated PDA were operated on for closures of the ductus in the Cardiac Surgery Unit of Soavinandriana Teaching Hospital.However, children who had a complex congenital heart disease or an associated PDA with other cardiac malformation have been sent to France.
This study included all children who underwent a surgical closure of an isolated patent ductus arteriosus during the first 5 years of practice of the Malagasy team.Demographic data, birth weight, extracardiac abnormalities, clinical signs, diagnostic imaging, the diameter of the ductus, the surgical waiting time after diagnosis, surgical procedures, and hospital left stays were analyzed.
Data were collected from cardio pediatrician consultation sheets, echocardiography reports, pre-anesthetic consultation sheets, operative reports, and hospitalization records.
Data were recorded with Microsoft Excel 2016 and then analyzed with SPSS 21.0 software.Data are presented as absolute values and frequency, mean and standard deviation, and range according to the sample distribution.

III. RESULTS
One hundred and four children have been recensed in this period of study.There was a predominance of female gender with 68 females (65.38%) and 36 males (34.62%), giving sex ratio of 52%.The average age was 29.75±29.25 months (from 4 months to 156 months).Population was nursling in 72.12%.
Fifteen children were born with prematurity (14.42%).There were 25 children (24.04%) born with a low birth weight in our study (Table I).The mean birth weight was 2724±487.74g.
Thirteen patients (12.5%) had extracardiac abnormalities associated with PDA: 6 cases of Trisomy 21, 5 cases of thoracic deformation and 2 cases of craniosynostosis.
The average age of diagnosis was 18.10±22.61months.PDA was symptomatic in 87 cases (83.65%).The most common symptomatology were recurrent lung infections (51.92%) and failure to thrive (25.96%) (Table I).There were no symptoms in 17 children (16.35%) and the diagnosis was performed after doing echocardiography for the reason of cardiac murmur or cardiomegaly on routine chest X-ray.On clinical examination, cardiac auscultation showed a murmur of PDA (76.92%) and loud P2 at the left second intercostal space (58.65%).Electrocardiogram tracing showed left ventricular hypertrophy in 46% and biventricular hypertrophy in 12.5% of cases.
The mean delayed time for waiting surgical after diagnosis was 7.28±16.13months (Table III).All ductus were closed by an open surgery.The child was placed in the right lateral decubitus position prior to surgery (Fig. 2).The surgical approach is a left postero-lateral thoracotomy (Fig. 3).Surgical procedures consisted of section and suture after clamping the ductus.The ductus has been sutured by Blalock-Taussig procedure with prolene 5-0 or 6-0.Fig. 4 shows the sutured ductus arteriosus.After the closure of the ductus, the chest was closed after the insertion of a chest tube with suction.
Postoperative medication is often associated with oxygen therapy, anti-biotherapy, painkillers, and diuretics.Chest Xrays were routinely taken 24 hours after surgery (Fig. 1B).Postoperative course was simple for all children.A follow-up echocardiography is performed before hospital discharge.No postoperative death was found during hospitalization.The mean duration of hospitalization was 7.33±0.72days, from 5 to 10 days.

IV. DISCUSSION
The practice of cardiac surgery remains a challenge in sub-Saharan African countries, due to the lack of cardiac surgeons and the cost of the operation.Humanitarian aid from international organizations enabled patients in low-income countries like Madagascar to have access to surgery for congenital heart disease.In sub-Saharan Africa, the prevalence of patent ductus arteriosus in newborns was 24.5% [5].However, the rate of access to surgical closure remains low.Overall, only around 3% of children with congenital heart disease have access to surgery in sub-Saharan Africa [6].The Malagasy team's autonomy in the surgical management of patent ductus arteriosus reduces missionary travel expenses.This allows us to increase the number of children to be operated on with the same budget offered by the sponsoring organizations.
In Western countries, the average age of patients undergoing surgical closure of the patent ductus arteriosus was somewhat younger than in low-income countries.The average age of patients reported in the African studies was 45 months in the Ba PS study [7], 47 months in the Gribaa R study [8] and 8 months in the Ezemba N study [9].Our study showed similar results to these African studies, with a mean age of 29.75 months.In sub-Saharan Africa, the majority of patent ductus arteriosus is often discovered at a distance from birth, due to the absence of systematic prenatal screening.After diagnosis, patients often do not undergo immediate surgery for a variety of reasons, such as financial problems or the presence of a lung infection.This may explain the somewhat advanced age of patients undergoing surgical closures of patent ductus arteriosus in sub-Saharan African countries such as Madagascar.
According to a recent meta-analysis by Borges-Lujan M, there is no significant gender difference in the risk of developing patent ductus arteriosus [10].However, the predominance of women in the population of patients operated on for closure of the ductus arteriosus is often observed in several studies [7], [11], [12].However, the rate of female predominance varied according to the study: 63% in the Ba PS study [7], 87% in the Onakpoya UU study [11] , and 84% in the Nyawawa ET study [12].Our study showed a similar result for the predominance of females (65%).However, other studies have shown a male predominance in patients who underwent surgical closure of PAD, such as Tort's study (52%) [13] and Avila-Alvarez's study (52%) [14].
Prematurity is one of the major risk factors implicated in the occurrence of patent ductus arteriosus.Several researchers have published the significant risk of patent ductus arteriosus in premature infants.The incidence of patent ductus arteriosus (PDA) in premature neonates varies according to the gestational age (2).In our study, 14% of children were born prematurely.The prematurity rate in our study was close to that in the Faim DR study (11%) [15].However, other studies have shown a higher rate of premature births, such as Tort's study [13].There is a high incidence of PAD in the Mean birth weight was 2724 g in our study.In the study of Omokhodion SI, the average birth weight was 1712 g for premature babies and 2946 kg for full-term babies.
The presence of trisomy 21 associated with PDA has been reported by several authors.The association of patent ductus arteriosus with chromosomal abnormalities is estimated at 10% [16].In our study, six children had trisomy 21 (5%).Gribaa's study showed a higher rate (11%) of trisomy 21 associated with the patent ductus arteriosus [8].
In sub-Saharan African studies, the majority showed a very high rate of symptomatic forms, in contrast to studies carried out in Western countries.In our study, 87 cases of PDA were symptomatic (83%) and 17 cases were asymptomatic (16%).This predominance of symptomatic forms was also observed in other African studies such as the Ba Ps study [7], the Onakpoya UU study [12] and Gribaa R study [8].The high rate of symptomatic forms in African studies could be explained by the absence of systematic screening of premature newborns.
Recurrent respiratory infection and failure to thrive were the main symptoms of PAD in various studies.In late forms, dyspnea due to heart failure is sometimes the circumstances of the diagnosis.In our study, the commonest symptoms were recurrent lung infection (51%) and failure to thrive (25%).Our results are similar to those of the Ba PS study [7] and the Onakpoya UU study [11] on the predominance of recurrent bronchopulmonary infections and failure to thrive in the symptom of children who underwent surgical closure of PAD.However, dyspnea is the main symptom of PDA in Tort's study [13].
The diagnosis of PDA is usually performed early in Western countries.In sub-Saharan Africa, diagnosis is often delayed until the clinical signs of pulmonary overload related to the left-right shunt become established.The mean age of diagnosis was 18.10 months in our study.The mean age at diagnosis of children with PDA was higher than in our study in Gribaa's study (47.18 months) [8].However, the diagnoses were made earlier than in our study in Clyman RY's study (8.1 days) [17].The early age of diagnosis in Western studies could be explained by the systematic screening of premature and newborn infants for congenital heart disease.
Echocardiography is the gold standard imaging to make a confirmative diagnosis of PDA, to measure the transductal diameter, diagnose an associated congenital heart defect, estimate the shunt volume and to assess the hemodynamic significance.The ductus is considered small at <1.5 mm, moderate when it ranges between 1.5 and 3 mm, and large if the dimension exceeds 3 mm [18].The mean diameter of PDA was 5.17 mm.The predominance of large forms of PDA is usually observed in African studies such as in Ba's study [7] and in Gribaa's study [8] which the mean diameter was respectively 6 mm and 5.38 mm.The mean diameter was very large in the study of Animasahun [19].
A surgical wait is often observed in sub-Saharan African studies.The reasons for waiting for surgery were the unavailability of the technical platform, the expectation of the probability of spontaneous closure of small ductus, the risk of anesthesia in premature infants, the presence of concomitant bronchopulmonary infection and the financial reason.The average surgical waiting time was 7.28 months.In the Onakpoya UU study, half of the patients (50%) underwent surgery between 4 and 24 weeks after the diagnosis of PDA [11].There is a clear reduction in the average surgical waiting time in our study compared to when the missionaries operated on our patient (15.16 months).
The section-suture of the ductus arteriosus was performed for the first time by Dr. Robert Edward Gross in 1941 [20].At present, section-suture of the ductus arteriosus is the classic surgical technique used for the closure of PDA [21].Nevertheless, the technique of triple ligation of the ductus arteriosus has been published in a number of recent studies.The section-suture of the ductus was the only surgical technique used in our patients since the missionaries began the surgery of closure of the arterial duct in Soavinandriana Hospital.In the study of Ba PS, the technique used was triple ligation (4%), suture followed by ligation (45%), and ligation with a clip (51%) [7].But, ligation was the technique used in the study of Ezemba (9) and Nyawawa [12].Percutaneous closure using an amplantzer device or coil is the technique used to close the ductus arteriosus in other African studies of Gribaa [8] and Animasahun [19].
The early postoperative course of surgical closures of PDA is often favorable.The mortality rate is very low.Death is often linked to the presence of other congenital heart defects.However, the mortality rate published by other African studies remains high.No deaths were recorded in our study.This result could be explained by the fact that surgery was only performed on children with isolated PCA.In sub-Saharan African studies, the mortality rate was 1% in Ba's study [7], 3% in Tort's study [13] , and 10% in Ezemba's study [9].There is no death recorded in Animasahun's study [19].
The length of hospital stay depended on the early postoperative course.A short hospital stay is often sufficient for isolated PCA closure.The presence of postoperative complications or other congenital heart defects may require a longer hospital stay.The mean hospital length stay was 7.33 days in our study.In African studies, the average hospital stay is often less than 7 days: 5 days in Ba's study [7] and 6 days in Ezemba's study [9].However, some authors published a shorter average hospital stay than our result: 3.9 days in Koirala's study [22] and 5 days in Tort's study [13].

TABLE I :
BIRTH WEIGHT, EXTRACARDIAC ABNORMALITIES AND Fig. 1.Chest X-ray (A: before surgery, B: after surgery).

TABLE III :
TIME FOR WAITING SURGERY, HOSPITALIZATION LEFT STAY Time for waiting surgery /