Late mortality after cardiac interventions over 10-year period in two Cameroonian government-owned hospitals

A systematic review and meta-analysis on outcomes of valvular heart surgery in Africa

INTRODUCTION

The prevalence of valvular heart diseases remain considerably high in Africa, largely but not solely due to rheumatic heart disease. Valvular heart surgeries have emerged as the cornerstone in their management. While several studies have reported data on outcomes following heart valve surgery in many developed countries, there is a staggering paucity of data and evidence reporting the outcomes in the Africa population. The aim of this study is to report the perioperative outcomes following valvular heart surgery in Africa.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-analysis guideline was utilized. Electronic searches were performed using PubMed, African journal online, and Research gate from inception to June 2023. The primary endpoints were overall mortality and 30-day mortality, and secondary endpoints included postoperative complications, length of hospital, and intensive care stays. The outcome data were pooled together and analyzed with the random effect model for proportions and mean for meta-analysis using the R software.

RESULTS

This systematic review identified 31 studies that fulfilled the study eligibility criteria and all were observational studies. The countries in which these studies were carried out include South Africa, Ethiopia, Egypt, Mali, Rwanda, Nigeria, Cameroon, Ghana, Senegal, Tanzania, and Kenya. Statistical analysis reported a pooled overall mortality of 10.48% and a pooled 30-day mortality of 4.59%.

CONCLUSION

Several obstacles, such as lack of financial resources and inadequate infrastructure, continue to impede valvular heart surgery practice in many parts of Africa. Future studies need to focus on identifying factors associated with this poor early mortality.

A glimpse of hope: cardiac surgery in low- and middle-income countries (LMICs)

Currently, more than five times more people live in low- and middle-income countries (LMICs) than in high-income countries (HICs). As such, the downward trend in cardiac surgical needs in HICs reflects only the situation of one sixth of the world population while the vast majority living in LMICs has still no or limited access to life saving heart operations. In these countries, rheumatic heart disease (RHD) still accounts for a significant proportion of cardiac surgical needs. In low- and lower-middle income countries it remains the single most common cardiovascular disease in young adult and adolescent patients in need of heart surgery outweighing other indications such as congenital cardiac defects almost 4-fold. Compared to HICs with their predominance of calcific aortic stenosis in the elderly mitral valve surgery is required in >90% of the largely young patients with RHD in low-income countries (LICs) and still in 70% of the often middle aged patients in middle-income countries (MICs). Although recent government initiatives in LICs led to the establishment of local, independent cardiac surgical services gradually replacing fly-in missions, these centers still only cover less than 2% of the needs of their populations. In MICs, cardiac surgical needs continually grow with the emergence of degenerative diseases. As such, in spite of the concomitant growth of cardiac surgical capacity, significantly less than half the estimated patients in need have access. Capacities in LICs range from 0.5 to 7 cardiac operations/million population; 100-481/million in MICs and >1,200/million in HICs such as the USA and Germany. While a new level of awareness of the scope and magnitude of the problem has begun to emerge in LICs and the establishment of local cardiac surgical capacity has given rise to a glimpse of hope, the challenges of expanding these fledgling services to a significant proportion of the population still seem insurmountable. Challenges in MICs are on the other hand the widening gap between private cardiac medicine for the affluent few and overwhelmed public services for the many and the rural urban divide with the underappreciation of the ongoing dominance of RHD in the rural and indigent population on the other. Overshadowing all LMICs is the low level of valve-repair skills associated with insufficient cardiac surgical capacity and the unavailability of suitable replacement valves which address the young age of the patients and the difficulties of anticoagulation in a socioeconomic environment distinctly different from the elderly patients of HICs.