Congenital Heart Disease in Low- and Lower-Middle-Income Countries: Current Status and New Opportunities.

PURPOSE OF REVIEW: The paper summarises the most recent data on congenital heart disease (CHD) in low- and lower-middle-income countries (LLMICs). In addition, we present an approach to diagnosis, management and interventions in these regions and present innovations, research priorities and opportunities to improve outcomes and develop new programs. RECENT FINDINGS: The reported birth prevalence of CHD in LLMICs is increasing, with clear evidence of the impact of surgical intervention on the burden of disease. New methods of teaching and training are demonstrating improved outcomes. Local capacity building remains the key. There is a significant gap in epidemiological and outcomes data in CHD in LLMICs. Although the global agenda still does not address the needs of children with CHD adequately, regional initiatives are focusing on quality improvement and context-specific interventions. Future research should focus on epidemiology and the use of innovative thinking and partnerships to provide low-cost, high-impact solutions.

Outcomes Following Neonatal Cardiac Surgery in Cape Town, South Africa.

BACKGROUND: Neonatal Cardiac Surgery has developed significantly since its advent, with improved outcomes, survival, and physiological repair. Limited programs offer neonatal cardiac surgery in emerging economies. We report our experience with neonates undergoing cardiac surgery in our cardiac surgery program. METHODS: We performed a secondary data analysis on all neonates aged ≤ 30 days undergoing congenital cardiac surgery from April 1, 2017 to March 31, 2020, including outcomes up to 30-days post-surgery. RESULTS: A total of 859 patients underwent cardiac surgery at our center, of these 81 (9.4%) were neonates. The proportion of neonates increased annually (8.7%, 9.6%, and 10.2%). There were 49 (60%) male patients, and 32 (40%) had surgery in the second week of life. Fourteen (17%) were premature, four (5%) had a major chromosomal abnormality, five (6%) a major medical illness, and eight (10%) a major noncardiac structural anomaly. The Risk Adjustment for Congenital Heart Surgery (RACHS) categorization of surgery was predominantly RACHS 3; n = 28 (35%) and 4; n = 23 (29%). Hours in the intensive care unit (ICU) were extensive; median 189 [interquartile range (IQR): 114-286] as were hours of ventilation; median 95 [IQR 45-163]. Almost 60% (n = 48) of procedures were complicated by sepsis, as defined in our database. The in-hospital mortality rate was 16% (n = 13); the 30-day mortality rate was 19.8% (n = 16). CONCLUSION: The proportion of neonates in our service increased over the period. Focused strategies to shorten prolonged ICU stay and decrease rates of bacterial sepsis in neonates are needed. A multidisciplinary, collaborative heart-team approach is crucial for best outcomes.

The impact of COVID-19 on a South African pediatric cardiac service: implications and insights into service capacity.

Background and Objectives: The Western Cape public pediatric cardiac service is under-resourced. COVID-19 regulations are likely to have long-term effects on patient care but may provide insight into service capacity requirements. As such, we aimed to quantify the impact of COVID-19 regulations on this service. Methods: An uncontrolled retrospective pre-post study of all presenting patients over two, one-year periods; the pre-COVID-19 period (01/03/2019-29/02/2020) and the peri-COVID-19 period (01/03/2020-28/02/2021). Results: Admissions decreased by 39% (624 to 378) and cardiac surgeries decreased by 29% (293 to 208) in the peri-COVID-19 period, with an increase in urgent cases (PR:5.99, 95%CI:3.58-10.02, p < 0.001). Age at surgery was lower in the peri-COVID-19 period, 7.2 (2.4-20.4) vs. 10.8 (4.8-49.2) months (p < 0.05), likewise, age at surgery for transposition of the great arteries (TGA) was lower peri-COVID-19, 15 (IQR:11.2-25.5) vs. 46 (IQR:11-62.5) days (p < 0.05). Length of stay 6 (IQR:2-14) vs. 3 days (IQR:1-9) (p < 0.001), complications (PR:1.21, 95%CI:1.01-1.43, p < 0.05), and age-adjusted delayed-sternal-closure rates (PR:3.20, 95%CI:1.09-9.33, p < 0.05) increased peri-COVID-19. Conclusion: Cardiac procedures were significantly reduced in the peri-COVID-19 period which will have implications on an overburdened service and ultimately, patient outcomes. COVID-19 restrictions on elective procedures freed capacity for urgent cases, demonstrated by the absolute increase in urgent cases and significant decrease in age at TGA-surgery. This facilitated intervention at the point of physiological need, albeit at the expense of elective procedures, and also revealed insights into capacity requirements of the Western Cape. These data emphasize the need for an informed strategy to increase capacity and reduce backlog whilst ensuring minimal morbidity and mortality.Graphical Abstract.

Investigation of Copy Number Variation in South African Patients With Congenital Heart Defects.

BACKGROUND: Congenital heart disease (CHD) is a leading non-infectious cause of pediatric morbidity and mortality worldwide. Although the etiology of CHD is poorly understood, genetic factors including copy number variants (CNVs) contribute to the risk of CHD in individuals of European ancestry. The presence of rare CNVs in African CHD populations is unknown. This study aimed to identify pathogenic and likely pathogenic CNVs in South African patients with CHD. METHODS: Genotyping was performed on 90 patients with nonsyndromic CHD using the Affymetrix CytoScan HD platform. These data were used to identify large, rare CNVs in known CHD-associated genes and candidate genes. RESULTS: We identified eight CNVs overlapping known CHD-associated genes (GATA4, CRKL, TBX1, FLT4, B3GAT3, NSD1) in six patients. The analysis also revealed CNVs encompassing five candidate genes likely to play a role in the development of CHD (DGCR8, KDM2A, JARID2, FSTL1, CYFIP1) in five patients. One patient was found to have 47, XXY karyotype. We report a total discovery yield of 6.7%, with 5.6% of the cohort carrying pathogenic or likely pathogenic CNVs expected to cause the observed phenotypes. CONCLUSIONS: In this study, we show that chromosomal microarray is an effective technique for identifying CNVs in African patients diagnosed with CHD and have demonstrated results similar to previous CHD genetic studies in Europeans. Novel potential CHD genes were also identified, indicating the value of genetic studies of CHD in ancestrally diverse populations.

PROTEA, A Southern African Multicenter Congenital Heart Disease Registry and Biorepository: Rationale, Design, and Initial Results.

Objectives: The PartneRships in cOngeniTal hEart disease (PROTEA) project aims to establish a densely phenotyped and genotyped Congenital Heart Disease (CHD) cohort for southern Africa. This will facilitate research into the epidemiology and genetic determinants of CHD in the region. This paper introduces the PROTEA project, characterizes its initial cohort, from the Western Cape Province of South Africa, and compares the proportion or "cohort-prevalences" of CHD-subtypes with international findings. Methods: PROTEA is a prospective multicenter CHD registry and biorepository. The initial cohort was recruited from seven hospitals in the Western Cape Province of South Africa from 1 April 2017 to 31 March 2019. All patients with structural CHD were eligible for inclusion. Descriptive data for the preliminary cohort are presented. In addition, cohort-prevalences (i.e., the proportion of patients within the cohort with a specific CHD-subtype) of 26 CHD-subtypes in PROTEA's pediatric cohort were compared with the cohort-prevalences of CHD-subtypes in two global birth-prevalence studies. Results: The study enrolled 1,473 participants over 2 years, median age was 1.9 (IQR 0.4-7.1) years. Predominant subtypes included ventricular septal defect (VSD) (339, 20%), atrial septal defect (ASD) (174, 11%), patent ductus arteriosus (185, 11%), atrioventricular septal defect (AVSD) (124, 7%), and tetralogy of Fallot (121, 7%). VSDs were 1.8 (95% CI, 1.6-2.0) times and ASDs 1.4 (95% CI, 1.2-1.6) times more common in global prevalence estimates than in PROTEA's pediatric cohort. AVSDs were 2.1 (95% CI, 1.7-2.5) times more common in PROTEA and pulmonary stenosis and double outlet right ventricle were also significantly more common compared to global estimates. Median maternal age at delivery was 28 (IQR 23-34) years. Eighty-two percent (347/425) of mothers used no pre-conception supplementation and 42% (105/250) used no first trimester supplements. Conclusions: The cohort-prevalence of certain mild CHD subtypes is lower than for international estimates and the cohort-prevalence of certain severe subtypes is higher. PROTEA is not a prevalence study, and these inconsistencies are unlikely the result of true differences in prevalence. However, these findings may indicate under-diagnosis of mild to moderate CHD and differences in CHD management and outcomes. This reemphasizes the need for robust CHD epidemiological research in the region.