The Pocket Echocardiograph: Validation and Feasibility

• Published in: Echocardiography (Mount Kisco, N.Y.) N.Y.), 2010-08, Vol.27 (7), p.759-764
• Main Authors: Culp, Benjamin C., Mock, Jonathan D., Chiles, Christopher D., Culp, William C.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Echocardiography - instrumentation; ejection fraction; Equipment Design; Equipment Failure Analysis; Feasibility Studies; Female; hand-carried ultrasound; Humans; imaging; Male; Middle Aged; Miniaturization; Stroke Volume; transthoracic echocardiography; Ventricular Dysfunction, Left - diagnostic imaging; ventricular function; Young Adult
• ISSN: 0742-2822; 1540-8175
• DOI: 10.1111/j.1540-8175.2009.01125.x

Background: A new, miniaturized ultrasound device, the pocket echocardiograph (PE), is highly portable and can be carried inside a lab‐coat pocket. Studies of this device are limited and have not examined the use by novice echocardiographers. We hypothesize that a novice echocardiographer can use PE to produce interpretable cardiac images, and that both novice and expert echocardiographers can use PE to accurately quantify ejection fraction. Methods: Unselected subjects (n = 40) in an echocardiography laboratory underwent blinded formal transthoracic echocardiography (TTE) and PE (Acuson P10, Siemens, Mountain View, CA, USA). A cardiology fellow with 2 months of echocardiography training acquired PE images. The fellow and an experienced echocardiographer interpreted the PE studies offline in a blinded fashion. To assess adequacy, studies were graded as technically adequate, limited, or inadequate. A visual estimation of ejection fraction was made. Comparisons were made to the formal reported TTE. Results: Subjects were heterogeneous, 43% male; age 64 ± 17 years, and ejection fraction 52.4%± 12.3%. All PE studies were interpretable, and the vast majority of PE and TTE images were considered technically adequate (77.5% and 85% respectively; P = 0.32). Ejection fraction showed a good correlation, bias, and limits of agreement for the fellow's interpretation (r = 0.78, −5.9%, ±16.6%) with stronger association for the experienced echocardiographer (r = 0.88, −0.8%, ±11.4%). Conclusion: Novice echocardiographers using the PE can produce adequate quality images. Both expert and novice echocardiographers can use PE to quantify ejection fraction over a broad range of patients. The device's low cost and portability may greatly expand the availability of bedside echocardiography for routine or urgent cardiovascular assessment. (Echocardiography 2010;27:759‐764)