Background: Acute dyspnea in emergency departments (ED) requires prompt and accurate diagnosis due to its high mortality and readmission rates. Conventional diagnostic methods are resource-intensive and time-consuming. This study aimed to evaluate the diagnostic accuracy and time to diagnosis of combined heart and lung ultrasound (HeaLus) compared to standard emergency department evaluation in patients presenting with dyspnea.

Methods: A prospective study was conducted in a cohort of 61 patients at the ED of Danderyd Hospital, Sweden. HeaLus examinations were performed alongside routine investigations. Diagnostic performance of HeaLus and ED evaluation was assessed for accuracy, sensitivity, specificity, positive predictive value, and negative predictive value, and agreement using Kappa index. Median time to diagnostics was compared between HeaLus and ED evaluation using Mann-Whitney U-test.

Results: Heart failure was the most common diagnosis (20%) among patients presenting with dyspnea. The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 95% (95% CI: [87%, 98%]), 98% (95% CI: [88%, 100%]), 90% (95% CI: [69%, 97%]), 95% (95% CI: [85%, 99%]), and 94% (95% CI: [74%, 99%]), respectively. The agreement between HeaLus and ED diagnoses was 0.88. Time to diagnosis was significantly reduced with HeaLus (21 min vs. 3 h and 28 min).

Conclusions: HeaLus offers rapid and accurate assessment of dyspnea. These results suggest that HeaLus could be valuable in optimizing patient management, particularly in settings with limited resources and long ED wait times.