Surgical and percutaneous management of Aboriginal Australians with rheumatic heart disease: Timeliness and concordance between practice and guidelines

Highlights

• Only half of Aboriginal patients with RHD receive surgery in a timely manner.

• Most patients who had accepted referrals for surgery had it within two years.

• The strength of guidelines recommendations significantly impacts referral rates.

Abstract

Background

Rheumatic heart disease (RHD) affects over 40 million people globally who are predominantly young and from impoverished communities. The barriers to valvular intervention are complex and contribute to the high morbidity and mortality associated with RHD. The rates of guideline indicated intervention in patients with significant RHD have not yet been reported.

Methods

From 2007 to 2017, we used the Australian Northern Territory Cardiac Database to identify patients with RHD who fulfilled at least one ESC/EACTS guideline indication for mitral valve intervention. Baseline clinical status, comorbidities, echocardiographic parameters, indication for intervention, referral and any interventions were recorded.

Results

154 patients (mean age 38.5 ± 14.6, 66.1% female) were identified as having a class I or IIa indication for invasive management. Symptoms, atrial fibrillation and pulmonary hypertension were the most common indications for surgery (74.5%, 48.1%, 40.9%). From the onset of a guideline indication the actuarial rates of accepted referral and intervention within two-years were 66.0% ± 4.0% and 53.1% ± 4.4% respectively. Of those who were referred and accepted for intervention, 86% received it within 2 years. The rates of accepted referral for patients with class I indications were 72.5% ± 4.2% while class IIa indications were 42.5% ± 9.0% (p < 0.001).

Conclusions

Approximately half of Aboriginal patients with significant rheumatic mitral valve disease who met ESC/EACTS guideline indications for intervention received surgery or valvuloplasty within two-years. A significant difference in referral rates was found between Class I and Class IIa indications for valvular intervention.

Introduction

Rheumatic heart disease (RHD) affects over 40 million people globally, mostly from impoverished communities [1]. The valvular pathology of RHD is often complex and mixed mitral valve disease predominates [2]. Morbidity and mortality are usually caused by heart failure, atrial fibrillation (AF), pulmonary hypertension, stroke or infective endocarditis [2,3]. Surgical or percutaneous valve intervention remains the only robust treatment [4]. Early intervention is associated with superior clinical outcomes and delays can contribute to morbidity [[5], [6], [7]].

Expected age of death for people with RHD varies greatly. However, for those with significant disease it is rarely greater than 40 years without intervention [8]. In low and middle income countries the median age of death is 29 years [9]. Patients' baseline comorbidities, as well as the type and number of valve interventions also play a role in their long-term prognosis [10]. Barriers to health care are multifactorial and differ considerably between regions [11,12]. Although these barriers are acknowledged, they have not been quantified previously in RHD cohorts where they are likely to be significant.

Concordance between practice and established guidelines for mitral valve intervention are known to be poor for Class I indications [13]. In non-rheumatic populations, factors associated with a lower likelihood of intervention are advanced age, higher comorbidities and reduced left ventricular ejection fraction (LVEF) [14]. The rates of intervention for patients with guideline indications have not yet been studied in a rheumatic population.

The primary aim of this study is to determine the rate of intervention in RHD patients who have a guideline indication. The secondary aims are to examine factors associated with referral and guideline recommendations for intervention, as well as the differences in referral by indication class.