Improving Clinical Management of Rheumatic Heart Disease in Developing Countries: Focus on Indonesia

Rheumatic heart disease (RHD) presents a significant and escalating global health challenge, with its incidence rising by 70.49% from 1990 to 2019, affecting 40.50 million people worldwide by 2019. In Indonesia, RHD is endemic, with approximately 1.18 million individuals affected in 2017. RHD is an autoimmune consequence of acute rheumatic fever (ARF) following an infection by Group A Streptococcus. The ensuing progressive valvular fibrosis often results in complications such as heart failure, pulmonary hypertension, and atrial fibrillation. RHD primarily impacts young, productive individuals, imposing a considerable economic burden on developing countries.

This thesis investigates the clinical characteristics, ventricular function, modern echocardiographic parameters, prevention strategies, and surgical outcomes of patients with RHD, focusing primarily on the Indonesian context. Our initial study (Chapter 2) conducted at the National Cardiovascular Center in Indonesia revealed a cohort predominantly composed of females with an average age of 42.61 years. Common findings include atrial fibrillation, diminished right ventricular contractility, and increased pulmonary pressure, suggesting that many patients present with an advanced stage of the disease.

In Chapter 3, a comparison was made between patients with rheumatic mitral regurgitation and those with degenerative MR, revealing that rheumatic etiology independently correlates with more severe left ventricular (LV) systolic dysfunction. This indicates that, in addition to the mechanical hemodynamic stress of MR, intrinsic myocardial processes likely play a role in the LV dysfunction observed in RHD. Chapter 4 reviews the cardiovascular changes, both upstream and downstream, associated with the most common lesion, rheumatic mitral stenosis (MS).

Traditional prognostic indicators, such as left ventricular ejection fraction (LVEF), may obscure subtle pathologies. In Chapter 5, we examined the application of myocardial work (MW), an innovative approach that considers afterload. Patients with severe rheumatic MS exhibited impaired LV global longitudinal strain (LV-GLS) and global LV MW parameters in comparison to healthy controls, despite maintaining preserved LVEF. This finding highlighted the presence of subtle LV dysfunction that conventional methods failed to detect. Chapter 6 further established a significant correlation between MW efficiency and functional capacity (exercise duration) in patients with severe MS and preserved LVEF, thereby positioning MW as a valuable tool for assessing functional capacity in the absence of objective testing.

A systematic review (Chapter 7) has confirmed a significant correlation between high adherence to penicillin in secondary prevention and a reduction in both ARF recurrence and RHD progression. In the context of surgical interventions (Chapter 8), our findings indicate that the 30-day mortality rate for rheumatic mitral valve surgery exceeds that of non-rheumatic cases. Notably, mitral valve repair did not exhibit a significant survival benefit over mitral valve replacement, highlighting the necessity for individualized surgical planning.

The thesis concludes by synthesizing these findings and emphasizing the challenges associated with optimal management of RHD in Indonesia. We propose several interventions to enhance management, including improved risk stratification, organized follow-up, and the establishment of a heart valve clinic (HVC) model within tertiary and secondary hospitals, networked with primary healthcare facilities. This HVC model is aimed to optimize patient management and minimize costs.