A prospective implementation study across five remote First Nations Australian communities trained 32 staff—21 community health workers (CHWs), 8 nurses, and 3 doctors—to perform handheld echocardiographic screening for rheumatic heart disease (RHD) in 5–20 year olds. Over 14 months, only 360 scans were completed, with site-level population coverage ranging widely from 3% to 85%. Setup and training cost A$51,903 per site plus A$9,858 annually in ongoing support. Key barriers included device unavailability, charging failures, upload delays, and the burden of "invisible work" that competed with scanning opportunities.
Rheumatic heart disease—caused by repeated untreated streptococcal infections—remains a stark health equity failure, disproportionately affecting Indigenous Australians at rates resembling low-income nations. Task-sharing echocardiography has theoretical appeal: it decentralizes a cardiology-dependent skill to frontline workers closer to high-burden communities. Yet this preprint, not yet peer-reviewed, reveals a persistent implementation gap between training capacity and sustained operational delivery. The 3–85% coverage range signals that structural and organizational factors—not clinical competence—are the limiting variables. The realist evaluation framework adds genuine methodological value by surfacing how role legitimacy shapes CHW performance, a mechanism often ignored in efficacy trials. Practically, the findings suggest that training alone is insufficient without policy-level recognition of CHW scanner roles and logistical infrastructure support. The event-based screening model proposed as a complement deserves formal evaluation. For the broader global RHD screening agenda, this study is a valuable, cautionary real-world implementation signal rather than a paradigm shift.