Anticoagulation control challenges in patients with rheumatic heart disease and mechanical heart valves operated at a cardiac surgery center in a low-income country
Authors: Nhavoto C , Aissa S , Estefane S , Menete A , Ferreira B 
Published: October 2024

Abstract

Background
Rheumatic heart disease (RHD) prevalence is very high in many low-income countries and valve replacement surgery can sometimes be the only available therapeutic strategy for the affected patients. Mechanical valves require lifelong anticoagulation and this can be very challenging in many poor countries where several barriers to effective anticoagulation monitoring and management are faced.

Methods
This is a retrospective study on 145 patients with RHD who underwent valve replacement surgery at a cardiac surgery center (CSC) in a low-income country between 2001 and 2022. The study aimed to evaluate the effectiveness of anticoagulation treatment to prevent thromboembolic events in patients with RHD with mechanical valves. The patients’ information such as social and demographic data, clinical features, surgical data and international normalized ratio (INR) records were collected and analyzed. Descriptive statistics were applied to the data and expressed as mean with standard deviation or simple frequencies and percentages.

Results
The mean age of the operated patients was 25.9 years (± 12.6) and 60% of them were female. Most of the patients (54%) were able to monitor their anticoagulation at the center and 8.2% of them monitored it in other hospitals. Three percent (3%) of the patients use a portable device to monitor their INR. These devices are provided by the CSC to help patients that live in distant provinces and are unable to go to the capital regularly. The device is held by one patient that is a focal point and helps monitor the INR of the other patients living in the same province. The INR results are communicated to the CSC by telephone text message.
Seven percent (7%) of the operated patients haven’t monitored their INR for more than one year and 24.8% of them were lost to follow-up. Sixty-four percent (64%) of the patients who monitor their INR at the center have an optimal control of their anticoagulation therapy. Most of the patients that were lost to follow-up (N=20) and most of the patients that haven’t checked their INR for more than one year (N=7) are patients who had aortic valve replacements. At least 20% of the patients that live in capital of the country and close to the CSC don’t monitor their anticoagulation regularly.

Conclusion
The surgical outcomes in RHD patients who undergo mitral valve repair are usually satisfactory. However, valve replacement is often the only feasible alternative and anticoagulation monitoring and management in these patients can become a serious problem especially to those coming from areas with limited resources. Illiteracy and poverty play a major role as barriers to effective monitoring of anticoagulation therapy. Efforts must be made to increase access to facilities where INR can be monitored. Our experience showed us that providing portable devices for INR monitoring to the patients living in remote areas can be a favorable short-term solution.