Novel handheld ultrasound technology to enhance non-expert screening for rheumatic heart disease in the Republic of Palau: A descriptive study

Aim: Non-expert training in rheumatic heart disease (RHD) detection is a valuable strategy in resource-limited settings. Here we present an innovative handheld ultrasound application featuring views of correct probe position, imaging protocol and echocardiographic loops of RHD pathology versus normal, accessible during real-time scanning. Methods: This prospective study was implemented into a pre-existing school health screening programme at an elementary school in Koror, Palau. Six learners with no prior ultrasound experience were taught a simplified screening protocol in which a mitral regurgitation jet ≥1.5 cm and/or presence of aortic insufficiency were considered a positive screen. All consented children underwent echocardiographic screening by experts with standard portable echocardiography. All positive cases and 25% of negative cases were referred for handheld scans by learners. Results: A total of 26 (4.1%) children were diagnosed with borderline or definite RHD. Mean sensitivity and specificity compared to expert RHD diagnosis over all learners was 71% (standard deviation (SD) 11.3) and 92% (SD 4.9), respectively. For the three highest scanning learners, mean sensitivity was 88% (SD 4.9) and mean specificity was 90% (SD 5.7). For all definite RHD cases, sensitivity was 100% for all but one learner, who achieved sensitivity of 60%. The novel application was used in 229 of 624 (36%) of all handheld scans and 50 of 112 (45%) of expert-diagnosed positive scans, with protocol and reference features most frequently used. Utilisation of the novel application overall decreased per day of scanning per learner. Conclusion: Adjunctive handheld ultrasound technology may help ease non-experts into RHD screening.