Pocket-sized echocardiography for screening structural heart disease: diagnostic accuracy and cost-effectiveness for population-based studies.

Background: The standard transthoracic echocardiography has some limitations in emergent and community-based situations. The emergence of pocket-sized ultrasound has led to influential advancements.
Methods: In this prospective study, in the hospital-based phase, children with suspected structural heart diseases were enrolled. In the school-based phase, healthy children were randomly selected from six schools. All individuals were examined by experienced operators using both the standard and the pocket-sized echocardiography.
Results: A total of 73 individuals with a mean age of 9.9 ± 3.2 years in the hospital-based cohort and 143 individuals with a mean age of 12.8 ± 2.9 years in the school-based cohort were examined. The agreements between the standard and the pocket-sized echocardiography were good or excellent for major CHDs in both cohorts (κ statistics > 0.61). Among valvular pathologies, agreements for tricuspid and pulmonary valves' regurgitation were moderate among school-based cohorts (0.56 [95% confidence interval 0.12-1] and 0.6 [95% confidence interval 0.28-0.91], respectively). The agreements for tricuspid and pulmonary valves' regurgitation were excellent (>0.9) among hospital-based population. Other values for valvular findings were good or excellent. The overall sensitivity and specificity were 87.5% (95% confidence interval 47.3-99.7) and 93.8% (95% confidence interval 85-98.3) among the hospital-based individuals, respectively, and those were 88% (95% confidence interval 77.8-94.7) and 68.4% (95% confidence interval 56.7-78.6) among the school-based individuals, respectively. The cost of examination was reduced by approximately 70% for an individual using the pocket-sized device.
Conclusions: When interpreted by experienced operators, the pocket-sized echocardiography can be used as screening tool among school-aged population.