OBJECTIVES: The purpose of this study was to evaluate the value of a hand-carried portable ultrasound device in the emergency department for patients with cardiomegaly and evaluate its impact on diagnosis and treatment. We compared the results of the portable ultrasound with the results of physical examination and with standard echocardiograph (SE) in the cardiomegaly patients in emergency department. BACKGROUND: Recently, small portable ultrasound devices have been introduced, and they need more extensive study to evaluate their application. METHODS: We used the OptiGo (Agilent Technologies, Andover, MA) portable device to evaluate emergency patients, and compared it with two SE devices available for this study, the Hewlett Packard (Sono 5500; Andover, MA) or the Vingmed (System V; Horten, Norway). Each of 100 patients was studied by physical examination first then examined with the portable ultrasound and standard echocardiography. The yields from physical examination and portable echocardiography were compared and results of the standard and portable were also compared. RESULTS: There were a total of 243 cardiovascular findings detected by the standard echocardiographic examination in the 100 patients studied. Cardiac examination failed to detect 40% of the overall findings but the portable device missed only 17% of all findings. The portable device evaluated 201 conditions correctly (83%) and missed relevant clinical findings in 37 (17%) as compared to standard echocardiography, but in only 12 (5%) were these findings of major importance As an overall measure of diagnostic value, the portable device would have added to clinical judgment, thus boosting diagnostic accuracy from 62% to 83%. CONCLUSIONS: Portable ultrasound technology can provide rapid, readily available and important clinical information for emergency physicians in the management of emergency patients with cardiomegaly.