Is Pocket Mobile Echocardiography the Next-Generation Stethoscope? A Cross-sectional Comparison of Rapidly Acquired Images With Standard Transthoracic Echocardiography

Abstract

BACKGROUND A new miniature high-resolution pocket-mobile echocardiographic (PME) device has become available to clinicians, but there are no data available comparing this technology with standard transthoracic echo (TTE) examination. OBJECTIVE To assess the potential validity of PME imaging as a quick assessment of cardiovascular disease by direct comparison to standard TTE. DESIGN Ultrasonographers attempted to acquire seven standard echocardiography views with the PME prior to performing comprehensive standard TTEs. In blinded fashion, images from the two modalities were compared by two experienced echocardiographers and two cardiology fellows. PRIMARY FUNDING SOURCE This work was funded in part by Scripps Health and the NIH UL1 RR025774 (Scripps Translational Science Institute, Clinical and Translational Science Award). SETTING Scripps Clinic/Green Hospital PATIENTS 97 consecutive unselected patients MEASUREMENTS Comparisons were made in regards to ejection fraction (EF), segmental wall motion abnormalities (WMA), left ventricular end-diastolic dimension (LVEDD), inferior vena cava (IVC) size, aortic and mitral valve pathology, and pericardial effusion. RESULTS PME images were adequate for interpretation of EF in 95% of the studies, LVEDD 95%, mitral valve 90%, WMA 83%, aortic valve 83%, and IVC 75%. Compared to standard TTE, PME interpretation by attendings and fellows had an accuracy of 97% and 93% for EF, respectively. Likewise, accuracy for WMA was 90% and 87% ; LVEDD 94% and 91%; aortic stenosis 97% and 95%; mitral abnormality 88% and 82%; and IVC size 81% and 74%. LIMITATIONS As this was a validation study of imaging alone, further evaluation with clinician image acquisition is needed. CONCLUSIONS PME images obtained rapidly by skilled ultrasonographers provide excellent visualization in the vast majority of patients and correlate well with standard, comprehensive TTE. Such validation needs to be extended to untrained clinicians in larger and diverse patient populations before broad dissemination of this technology can be recommended.

The Utility of Pocket-Sized Echocardiography to Assess Left Ventricular Systolic Function Prior to Permanent Pacemaker Implantation

“…Although this study commented on the accuracy of PSE compared to sTTE in a subset of patients, this was not the primary objective. Image accuracy has been previously well described in various other patient populations [7][8][9][10][11][12][13][14][15][16][17][18]. Finally, although this study validated the use of PSE in assessing LVEF, if more extensive information on cardiac structure and function is required clinically prior to PPM implantation sTTE is superior to that of PSE.…”

“…The use of the PSE to visualize left ventricular wall motion and systolic function has been previously evaluated. Several studies have demonstrated that the PSE can obtain interpretable images in the vast majority (85-100%) of patients by inexperienced sonographers, in both the inpatient and outpatient settings [10][11][12]. A complete sTTE study takes approximately 20-25 minutes to acquire, with a standard echocardiography machine costing approximately four times that of a PSE machine [20].…”

“…Its size confers the advantage of portability, making PSE ideal for point-of-care evaluation, either at the bedside, or in the outpatient setting. Previous studies have examined the diagnostic accuracy of PSE, its potential clinical applications, and the training involved to maximize safety and effectiveness of its use [7][8][9][10][11]. Several studies have reported that PSE can qualitatively assess LVEF with good reliability, even when a sonographic trainee acquires and/or interprets images [12][13][14][15][16][17][18].…”

Pocket-Sized Ultrasound as an Aid to Physical Diagnosis for Internal Medicine Residents: A Randomized Trial

“…Pocket-sized ultrasound devices are powerful tools that have been found to perform similarly to traditional high-end systems when used by experienced clinicians. [5][6][7][8][9][10][11][12][13] Internal medicine residents desire ultrasound training, but self-reported competence is low. 14 Several studies have shown that after brief training, residents can become competent in performing and interpreting basic ultrasound examinations.…”

The (Ultra)sound of Things to Come

“…Moving to a very different clinical setting, a current cross sectional study by Liebo et al comparing echocardiograms taken by a 'pocket mobile device' (VScan GE® Healthcare, Milwaukee) ( Figure 2) and a standard trans-thoracic echocardiogram (TTE) demonstrated highly correlative findings in most cardiac function measurements. 5 Within the constraints of a single centre study, they found that pocket mobile echocardiography (PME) yielded accurate assessments of ejection fraction and cardiac function, however there was a variance in accuracy with mitral valve abnormalities and inferior vena cava size. Interestingly, a similar comparison study using a different pocket echocardiograph (Acuson P10, Siemens®, Mountain View, CA) showed that there was a good correlation with standard TTE to quantify ejection fraction.…”