Estimating Congenital Cardiac Surgical Need in Africa Using Geographic Distribution of Surgeons

Introduction

Current estimates report that congenital heart disease (CHD) occurs in one out of every 100 live births globally [1–3], with 70% requiring medical and/or surgical intervention within the first year of life [4]. However, in low‑ or middle‑ income countries (LMICs), approximately 90% of patients are denied or do not receive standard of care [3], with one in three infants dying in the first month of life [5] due to limited access to centers with cardiac surgical capabilities [6].

Compared to high‑income countries such as the United States, access to cardiac surgical care in LMICs is limited—with countries in Sub‑Saharan Africa having both the fewest surgeons and centers [6, 7]. Contemporary studies assessing global access to congenital cardiac surgical care have presented the need gap by evaluating the number of surgeons or centers, on the basis of population [6, 7]. Studies of access to congenital cardiac surgical care in Africa have been limited to these generic global assessments. There has been no work that maps the incidence of CHD, characterizes geographic catchment areas, and considers travel distance for congenital cardiac surgical care as has been done in the US [8, 9]. This is especially pertinent in Africa given its vast geography as well as topography and potential to optimally locate centers with congenital cardiac surgical capabilities (the US is ~3.8 million square miles and Africa is ~11.7 million square miles).

The aim of this study is to utilize publicly available geographic data, estimates of population, disease incidence, and surgeon demographics in Africa to characterize geographic catchment areas serviced by the nearest congenital cardiac surgeon(s), estimate travel distance, and co‑register the incidence of CHD to truly establish the unmet surgical need.

Material and Methods

This cross‑sectional study did not involve human subjects and was conducted using publicly available data sources; therefore, IRB approval and informed consent were not required.

Results

Catchment areas

The population of each catchment area ranged from 628,440 individuals (served by one congenital cardiac surgeon in Port Said, Egypt) to 151,025,883 individuals (served by one congenital cardiac surgeon in Kampala, Uganda). The populations of each catchment area stratified by age group are shown in Figure 1.

Figure 1

The average distance a patient would need to travel (Figure 2) to see the congenital cardiac surgeon(s) in their catchment area, weighted by population, ranged from 1 km (0.62 miles) to 786.23 km (488.54 miles).

Figure 2

The ICCR for each catchment area ranged from 0.28 for regions served by Cairo, Egypt to 738.39 for regions served by Kampala, Uganda (Figure 3). Additionally, the ICCR for each catchment area was also generated using the alternative assumption that local surgeons might only be able to meet 75% or 50% of average US case volumes. These results are depicted in Supplementary Figure 1 and Supplementary Figure 2, respectively.

Figure 3

Subnational regions

A total of 779 subnational regions from 54 countries were included in the analysis. The estimated median was 700.81 (IQR: 211.14–1616.77) and the mean was 1406.89±89.73 incident cases of CHD across all subnational regions. The estimated annual number of index CHD cases by subnational region ranged from 1.19 cases (min‑max: 0.87–1.63) (Sowa Town, Botswana) to 38,987.86 cases (min‑max: 29,378.62–51,604.00) (Oromia, Ethiopia). A choropleth map depicting the incidence of CHD in each subnational region demonstrated the highest case density occurring in West Africa, the Horn of Africa, and along the coast of Southeast Africa (Figure 4). Additionally, rates of the incidence of CHD for each catchment area were tabulated (Supplementary Figure 3).

Figure 4

Congenital cardiac surgical need for each subnational region, incorporating distance from the nearest congenital cardiac surgeon, is shown in Figure 5, where blue lines link each subnational region to the location of the nearest congenital cardiac surgeon. Areas of greatest CHD surgical need occurred in the Horn of Africa along the coast of the Indian Ocean and centrally through the Congo Basin.

Figure 5

Comment

Prior work in estimating the clinical need gap in Africa has focused on traditional epidemiologic metrics to assess the limited access to congenital cardiac surgical care. We are the first to demonstrate that the problem is more complex by estimating that less than 5% of incident CHD cases can be accommodated by current surgical capacity and highlighting the role geography plays in limiting access to congenital cardiac surgery. In our work, examining 779 subnational regions comprising 63 catchment areas across Africa, we found that the average distance to travel for care by a congenital cardiac surgeon was 324.40 km (201.57 miles). Further, we demonstrate that the highest CHD surgical need is not isolated nor collocated to areas with the highest incidence of CHD but occurs in subnational regions that are most distant from the nearest congenital cardiac surgeons. These results suggest that increasing the number of congenital cardiac surgeons within Africa is imperative, but their geographic orientation is perhaps just as important.

Previous estimates of national cardiac surgical capacity in Africa have restricted their focus to standardizing cardiac centers (median: 0 centers per million people, IQR: 0–5) [6] and cardiac surgeons (mean: 0.19 surgeons per million people) [7] by population. Transportation alone becomes prohibitive for patients given the cost [18, 19] and lack of paved roads [20, 21]. Moreover, studies of the geographic distribution of congenital cardiac surgeons have been limited to high‑income countries such as the US [8, 22]; an analysis of current patient travel patterns in the US found that the median distance traveled to see a congenital cardiac surgeon is 38.5 miles [9]. A geographical analysis of congenital heart surgery patients based on population distribution, case complexity, and comprehensive care provision in the US has led to a proposal of regionalization of congenital cardiac surgery with fewer and more optimally relocated centers [8]. Similarly, since congenital cardiac surgery is needed direly and surgeons are distributed disparately, our work suggests that Africa also requires strategic structuring and geographic translocation of resources to areas of greatest need—easier said than done.

The dearth of funding that cardiac surgery receives from the largest donor of global health initiatives in the world (the US government) is noteworthy [23]. In 2016, 0.26% of the federal US budget (~$10.3 billion) was earmarked for global health initiatives [24]. Of these, funds directed to noncommunicable diseases, including cardiovascular disease and surgical conditions, jointly received only 3% of the earmarked allocations [25–27] (~$3 M). In contrast, HIV, tuberculosis, and malaria received over 50% of these funds [26]. In Africa, the mortality associated with cardiovascular and surgical conditions accounts for five times as many deaths as HIV, tuberculosis, and malaria combined [28–30]. While this is due to the groundbreaking advancements in the management of infectious diseases and efforts of global health champions over the past four decades, perhaps it is time to restructure funding models to better accommodate non‑infectious diseases.

In the absence of sizable global health funding as well as independent, sustainable, and sufficient congenital cardiac surgical services, there has been emphasis on utilizing non‑governmental organizations (NGOs) to mitigate the need gap for access to congenital cardiac surgeons in LMICs. Previous studies have identified approximately 81 NGOs providing congenital cardiac surgery in 96 LMICs [31, 32] performing an average of 8,047 operations annually across the globe, with the median performed by individual NGOs being 100 cases [32]. While this is important and improves the lives of recipients, from a system’s perspective, given our estimate of 1,045,000 annual incident cases of CHD unmet by local capacity, the need gap in Africa remains cavernous despite NGO involvement. Moreover, NGOs face unique challenges limiting their efficacy, including mistrust between transient NGO and local staff, post‑operative follow‑up, management of complications when surgical staff reside overseas, and disparate medical record keeping [33, 34].

It is clear from the efforts of these NGOs and the surgical mission work that is performed by smaller groups of surgeons that establishing equitable congenital cardiac surgical care across Africa is a long‑term goal. However, current efforts are often uncoordinated and only transiently address resources, staffing, and setting. These are three mission critical elements in developing a functional, long‑term surgical system that can meet the needs of patients with CHD. One of the most promising methods of developing congenital cardiac surgical workforces has been the establishment of twinning programs in which cardiac programs of excellence in resource‑rich settings are paired with developing cardiac programs in resource‑limited settings [35, 36]. This longitudinal partnership (typically >5 years) fosters bidirectional learning and skill development, which can include formal instruction (i.e. fellowship, perfusionist training, etc.), material support aimed at sustainability, and preparing developing centers to become training centers themselves [36], while minimizing challenges of the NGO model.

While these twinning models are promising, they are often limited by the constraints of a single institution and its cardiac surgical faculty, which also have competing interests to practice domestically to keep their departments afloat. For this reason, it might be beneficial to concert the efforts of NGOs, academic institutions, and individual surgeons through a professional organization such as the STS or the AATS to invest in a smaller subset of partners year‑round until they become training centers. This would effectively allow surgeons and local partners to pool expertise, staff, and resources in a singular space until it is ready to operate independently. Once a center is established, this program could expand to subsequent partners in an iterative process. An important derivative benefit is that the American Board of Thoracic Surgery (ABTS), STS, and AATS could leverage these twinning programs as a training conduit while also helping African nations better serve their populations.

Providing congenital cardiac care to African patients in remote locations will require innovation while new hospitals with these capabilities are established. General and surgical subspecialties have overcome similar challenges with teams of local surgeons leading mobile surgical units [37, 38]. Adoption of these ideas in the congenital cardiac context could be used to augment ongoing screening missions to remote locations performed by NGOs [39] and provide routine follow‑up care. Ultimately, while intended as a temporizing measure, this would also provide graduates from nascent African cardiac programs a flexible practice in addition to expanding access to care [37]. However, if mobile surgical units are not feasible because congenital cardiac surgery is so resource and staffing intensive, focus could also be shifted towards developing patient transport networks to the nearest center with congenital cardiac surgical capabilities.

Limitations

Our analysis has several limitations. We fully acknowledge that our methodology of collecting surgeon data from CTSnet is imperfect. However, this methodology has been used previously in other large‑scale geographic analyses of access to cardiac surgical services [7] and is necessary as no other continent‑wide registry of cardiothoracic surgeons exists. It also avoids the availability bias inherent in relying on information from regional contacts.

Catchment areas were constructed irrespective of national borders; assuming patients would be able to cross borders without difficulty due to medical need may not reflect geopolitical reality. Additionally, we calculated distances in a linear point‑to‑point fashion, not accounting for the actual road/transit networks patients might use, which are likely further and inefficient. However, as over 50% of roads are unpaved and the cost of air travel is prohibitive for a majority of citizens [21], this method is a reasonable approximation. Moreover, we assumed each surgeon could meet the average US case volume and that this case volume was composed solely of CHD. This is likely not the case, given the high incidence of rheumatic heart disease, and specialization in congenital caseloads is rare in LMICs. Finally, we assumed that the national estimates of CHD incidence were homogeneous throughout a country.

Conclusions

Across Africa, access to congenital cardiac surgical care is limited. Attention should be paid to the geographic distribution of surgeons as limited access is compounded by geographic distance. Potential solutions provide an opportunity for innovation and teamwork by local and international surgeons.

Disclosure Statement

The authors have nothing to disclose.

Funding Statement

No funding for this manuscript. LH is partially supported by an NHLBI T‑32 grant (1T32HL160520‑01A1).

Authorship Statement

All authors had access to project data and had a role in writing the manuscript.

Competing Interests

The authors have no competing interests to declare.

Additional Files

The additional files for this article can be found as follows:

Glossary of Abbreviations