The risk of Rheumatic Heart Disease (RHD) in relatives of Acute Rheumatic Fever (ARF) patients is poorly defined. This study aimed to determine RHD prevalence in first degree relatives of ARF patients using echocardiography.
Between 2014 – 2016, ARF cases were recruited from Auckland, New Zealand. Parents and siblings ≥ 4years were offered echocardiography. Echocardiograms were reviewed by a panel of three cardiologists and interpreted according to WHF 2012 criteria. RHD prevalence in family members was compared to reference population rates.
70 index cases were recruited. The median age of cases was 11 years (range 4 – 15 years). 55/70 (79%) were Pacific peoples and 15/70 (21%) were Māaori.
Echocardiography was performed in 94 parents and 132 siblings. 2 siblings had Definite RHD and 7 had Borderline RHD. 1 additional sibling had a known history of ARF/RHD. Echocardiography found 3 parents with Definite RHD and 3 with Borderline RHD. 2 parents had known clinically detected RHD.
Prevalence of RHD (Definite + Borderline) in siblings was 75 per 1,000 (95% CI 40 – 134 per 1,000) compared to 36 per 1000 (95% CI 30 – 42 per 1000) in NZ children from high-risk RF populations (p 0.02).
RHD prevalence in siblings of ARF cases is approximately twice the background rate. When a child is diagnosed with ARF, consideration should be given to offering siblings echocardiography. Where echocardiography resources are limited, RHD case detection efforts should be targeted at high-risk groups such as family members of known ARF/RHD cases.