rapid assessment of cardiac anatomy and function with a new

Eur J Echocardiography (2001) 2, 262–269doi:10.1053/euje.2001.0121, available online at http://www.idealibrary.com on

Rapid Assessment of Cardiac Anatomy and Functionwith a New Hand-carried Ultrasound Device

(OptiGoY): A Comparison with StandardEchocardiography

M. Rugolotto, B. S. Hu, D. H. Liang and I. Schnittger*

Division of Cardiovascular Medicine, Stanford University Medical Center, Stanford, California, U.S.A.

Aims: The aim of this study was to evaluate image qualityand accuracy of a new hand-carried ultrasound device,OptiGo� (Agilent Technologies) when compared tostandard echocardiography in the setting of a focusedexamination in the assessment of cardiac anatomy andfunction.

Methods and Results: One-hundred and twenty-onepatients were prospectively enrolled. Image quality andaccuracy in assessment of chamber sizes, left ventricular(LV) wall thickness and contractility, right ventricular (RV)function, mitral and aortic leaflet thickening, mitral annularcalcification, pericardial effusion and valvular regurgitationwere assessed. Two-dimensional (2D) findings were gradedon a four-point scale, except for LV function (six-point)and valvular leaflet opening (two-point). Colour Dopplerassessment of valvular regurgitation was graded on aseven-point scale. A one-point difference was consideredminor; a two or more point difference was consideredmajor. There was no statistically significant difference inimage quality between the two devices. For 2D data, the

number of total (minor and major) differences between thehand-carried and standard echocardiograph examinationswas significantly greater than the inter-observer variability(14·3% vs 10·7%, P<0·05), however, major differences alonewere not statistically different. For the colour Dopplerassessment of regurgitation there was a significant differ-ence between the devices for total (minor and major)differences, (40·0% vs 31·8%, P<0·007) however, thenumber of major differences is explained by inter-observervariability.

Conclusions: Image quality and diagnostic accuracy ofthe hand-carried device, OptiGo�, was adequate for thepurpose of performing a focused assessment of a limitednumber of 2D and Doppler parameters for the evaluationof cardiac anatomy and function.(Eur J Echocardiography 2001; 2: 262–269)� 2001 The European Society of Cardiology

Key Words: validation; hand-carried ultrasound device.

Introduction

Since the first clinical application of echocardiographyperformed by Edler and Hertz in the 1950s[1], theevolution of this diagnostic technique has been dra-matic, leading to better understanding of heart diseaseand improved cardiology practice[2]. Echocardiography

1525-2167/01/040262+08 $35.00/0

is frequently essential in the diagnosis of many cardiacconditions, and can be especially powerful as an adjunctto the physical examination. Nevertheless, the equip-ment is complex, expensive and not readily available inmany clinical settings. New devices of small size andweight may facilitate the full clinical potential of ultra-sound imaging, with true portability (hand-carried), easeof use and low cost[3].

In the past two decades some experiences with small,miniaturized, hand-held echocardiographs have beenreported. One of the first hand-carried devices was testedby Roelandt and his group in the 1970s (Minivisor,Organon Teknika) [Fig. 1(a)][4–6]. In the 1980s, Schwartzand Meltzer reported their experience with ScanMate

*Corresponding author: Ingela Schnittger, MD, Division of Cardio-vascular Medicine, Stanford University Hospital, 300 PasteurDrive, Room H-2157, Stanford, CA 94305-5233, U.S.A. Fax: (650)725-7568; E-mail: [email protected]

Received 20 June 2001; revised manuscript received 3 September2001; accepted 7 September 2001.

� 2001 The European Society of Cardiology

Evaluation of a New Hand-carried Ultrasound Device 263

(Damon Corp)[7,8]. These early prototypes wereequipped with two-dimensional imaging capabilities andclearly showed great potential[9], however suboptimalimage quality made interpretation more difficult[7].

Modern digital electronics allows for the design of anew generation of miniaturized, hand-carried echocar-diographs. These devices are equipped with 2D andcolour Doppler imaging capabilities. They have thepotential to significantly increase the timeliness of ultra-sound diagnosis at the point-of-care and to be used as apersonal ultrasound imager by physicians[3]. In order totest image quality and accuracy of a new prototypehand-carried device, specifically designed for echo-cardiography, we performed a validation study based ona side-by-side comparison with a standard echo-cardiograph. We chose to limit the assessment to 2Devaluation of chamber sizes, left ventricular (LV) wallthickness and function, right ventricular (RV) func-tion, cardiac valves, pericardial effusion and Dopplerassessment of valvular regurgitation.

Methods

Hand-carried Device

We used a prototype of OptiGo� (Fig. 1(b)), theall-digital, hand-carried echo device designed by AgilentTechnologies (Andover, MA, U.S.A.). The device is26·5�19·5 cm in size, weighs 2·5 kg and operates bothon AC power mode and on battery mode (nickel-metalhydride battery). The rechargeable battery allows about

60–75 min of continuous scanning. The ultrasounddevice consists of three main components: the13·7�10·3 cm LCD screen, the controls and a 2·5 MHzphased-array transducer. The screen and the controlsare connected together like a laptop computer. Thecontrols are extremely simple with the following controlbuttons: (1) grey-scale and/or colour gain; (2) near-fieldgrey-scale gain; (3) depth of field; (4) colour wedgelocation; (5) touch pad for linear measurements: caliperand eraser; (6) freeze/unfreeze image (scrolling backwardand forward); and (7) screen brightness. The devicecan perform two imaging modalities: 2D and colourDoppler. M-mode, continuous-wave and pulse-waveDoppler are not available. The prototype we used forthis study is not equipped with image storage possibili-ties. OptiGo� specifically was not designed to perform acomplete standard echocardiogram, but to allow forrapid ultrasonic assessment of cardiac anatomy andfunction.

Standard Echocardiography

Standard echocardiography was performed with aSonos 5500 echocardiograph (Agilent Technologies,Andover, MA, U.S.A.) equipped with harmonicimaging and multi-frequency transducers.

Study Population

The study population consisted of 121 consecutivelyenrolled patients (69 males, 52 females, mean age

Figure 1. Hand-carried devices. (a) Minivisor. The hand-carried device tested by Dr Roelandt (Rotterdam) in1978 (courtesy of the Author). (b) OptiGo�. The prototype of the hand-carried device that we used for thisstudy.

Eur J Echocardiography, Vol. 2, issue 4, December 2001

264 M. Rugolotto et al.

59·5�17·3, and range 24–91 years), referred forstandard echocardiography to the EchocardiographyLaboratory at Stanford University Hospital. Allpatients signed the consent form, approved by the localInstitutional Review Board. The patients were enrolledsubject to the availability of one of the authors, asseveral patients are studied simultaneously in ourlaboratory. The reasons for referral were: cardiomyo-pathy and assessment of LV function in 23 patients,ischaemic heart disease in 21 patients, clarification ofdyspnoea or a murmur in 20 patients, valvular heartdisease in 15 patients, surveillance of transplantedrecipient heart in 11 patients, investigation of arrhyth-mia and/or syncope in nine patients, pre-operative evalu-ation in six patients and 16 patients were studied formiscellaneous indications.

Readers

Two readers, both experienced cardiologists, conductedthe study. Reader A, a level III trained[10] echocardiog-rapher reviewed the videotapes of the standard echo-cardiogram. Reader B, a post-doctoral cardiology fellowwith level II training[10], performed and reported uponthe hand-carried device studies and also reviewedthe videotapes of the standard echocardiogram forinter-observer and intra-observer variability.

Hand-carried Device Examination Technique

Immediately after the standard examination performedby experienced sonographers, reader B, blinded to thestudy indications and to the standard echocardiogramresults, performed an echocardiographic examinationwith the hand-carried device. The echocardiogram wasbased on the parasternal long and short axis views andon apical four, two and three chamber views. Thescanning time was tabulated for each study. The follow-ing data were reported and subjectively graded by readerB as follows.

Image quality

Image quality was assessed according to a methodmodified after Hoffman et al.[11]. Images were graded ona four-point scale in the following manner: completeendocardial definition and wall thickening in all views(=1); inadequate visualization of one segment in oneview but adequate visualization of a comparable seg-ment within the same territory in another view (=2);inadequate visualization of more than one segment inone view but adequate visualization of comparablesegments within the same territory in another view(s)(=3); uninterpretable or inadequate visualization of oneor more whole territories (=4).

Two-dimensional data

Global LV function was graded on a six-point scale:normal (=1); mild (=2); mild-moderate (=3); moderate


(=4); moderate-severe (=5); and severe (=6) LV dys-function. Regional LV wall motion abnormalities wereevaluated in a subgroup of 49 consecutive patients. Asimplified wall-motion analysis system was used. Weconsidered four main segments: apical, anterior, lateraland infero-posterior. Posterior septum was consideredpart of the infero-posterior wall; anterior septum wasconsidered part of the anterior wall. Segmental motionwas subjectively graded on a four-point scale: normo-kinetic (=1); hypokinetic (=2); akinetic (=3); dyskinetic(=4). Left and right ventricular and atrial size, RVfunction, presence of LV hypertrophy, pericardialeffusion, aortic and mitral valve leaflet thickening andmitral annulus calcification were also graded on afour-point scale: normal findings (=1); mild (=2);moderate (=3); severe (=4) pathological findings. Aorticand mitral leaflet opening was graded on a two-pointscale: regular opening (=1); reduced opening andsuspicion of stenosis (=2).

Quantitative linear measurements

Quantitative linear measurements were evaluated in asubgroup of 61 consecutive patients. Measurementswere obtained from frozen 2D images in parasternallong axis and apical four-chamber views. Reader Bevaluated the LV end-diastolic diameter measured in theparasternal long axis view and the left and right atrialmajor diameters measured in the apical four-chamberview. Reader B reported upon the quantitative linearmeasurements after the subjective grading of imagequality, 2D and colour Doppler data.

Valvular regurgitation (colour Doppler)

Aortic, mitral, tricuspid and pulmonic valve regurgita-tion were graded on a seven-point scale: no regurgitation(=1); trace (=2); mild (=3); mild-moderate (=4);moderate (=5); moderate-severe (=6); severe (=7)regurgitation. During the study the company upgradedthe colour Doppler modality. Therefore we evaluatedregurgitation in two subgroups of patients, before theupgrade (99 patients, 57 males, mean age 58·6, range18–87) and after the upgrade (22 patients, 12 males,mean age 63·2, range 31–92).

Standard Echocardiogram VideotapeReading

OptiGo� did not provide videotape recordings so theprimary study with this instrument had analysed datareported on data sheets at the time of the study byreader B.

On standard echocardiography, both readers reviewedthe videotapes and reported upon image quality, 2Ddata and regurgitations and subjectively graded themwith the same grading scales described above. Wallmotion in the 49 patients noted above was observedagain on the recorded studies from the standard


echocardiograph. Reader B also reported upon chambermeasurements in the 61 patients noted above. Further-more, reader B reported upon LV end-diastolic diameterand left and right atrial major diameters measured inthe apical four-chamber view (after and independentlyfrom the subjective grading). Reader B evaluated thevideotapes from the standard echocardiograms, blindedto patients’ identity, using electronic blanking of theidentifying information on the video monitor.

Data Analysis

In order to assess the overall image quality of thehand-carried device, we compared the mean grade ofimage quality reported by reader B from his OptiGo�

examination with that of the standard echocardiographyexamination.

To assess the accuracy of the hand-carried device forthe subjective evaluation of 2D and colour Dopplerdata, we compared the grades obtained from the hand-carried device examination reported by reader B withthe grades obtained from the standard examinationreported by reader A (OptiGo� vs standard echocardio-graph comparison). Next, we compared the gradesobtained from the standard echocardiogram reported byreader A with those reported by reader B (inter-observervariability). In both comparisons, a grading difference ofone point was considered minor; a grading difference oftwo points or more was considered major. For aorticand mitral valve leaflet opening (two-point gradingscale) all differences were considered major. Our goalwas to establish whether the differences observed

between the hand-carried device and the standardechocardiograph could be accounted for by theinter-observer variability.

To assess the accuracy of the hand-carried device inthe evaluation of linear measurements, we compareddata from the OptiGo� examination with the standardechocardiogram as measured by reader B.

To assess the sensitivity and specificity of the hand-carried device in the evaluation of moderate to severepathologic findings, we compared the OptiGo� studiesreported by reader B vs the standard echocardiogramsreported by reader A.

Statistical Analysis

Differences in proportions for paired data were testedfor significance with McNemar’s test. Unpaired categ-orical data were tested using a Chi-squared test. Differ-ences in means were tested using a paired t-test. Resultswere considered significant if P<0·05.

Results

The average scanning time with the hand-carried devicewas 9·5 min (range 2·0–26 min). This was significantlyshorter than the average 40–45 min for the standardechocardiogram.

In standard echocardiograms a total of 93/2253(4·1%) and of 90/2253 (4·0%) findings were uninterpret-able according to reader A and reader B, respectively.The number of patients included in each measurement is

Table 1. Accuracy of the hand-carried device for two-dimensional data.

Data n

Number of total differences (%) Number of major differences (%)

Hand-carrieddevicevs SE

Inter-observervariability (SE) Intra-observer P



LV function 121 19 (15·7) 21 (17·4) 18 (14·9) 0·72 4 (3·3) 4 (3·3) 4 (3·3) 1·00LV size 121 14 (11·6) 5 (4·1) 9 (7·4) 0·03 0 (0·0) 0 (0·0) 0 (0·0) 1·00LV hypertrophy 121 39 (32·2) 22 (18·4) 32 (26·4) 0·01 5 (4·1) 4 (3·3) 2 (1·7) 0·74RV size 119 6 (5·0) 10 (8·4) 10 (8·4) 0·29 0 (0·0) 0 (0·0) 0 (0·0) 1·00RV function 119 10 (8·4) 10 (8·4) 12 (10·1) 1·00 2 (1·7) 2 (1·7) 0 (0·0) 1·00LA size 121 37 (30·6) 30 (24·8) 31 (25·6) 0·31 5 (4·1) 3 (2·5) 2 (1·7) 0·72RA size 121 27 (22·3) 14 (11·6) 20 (16·5) 0·03 1 (0·8) 2 (1·7) 0 (0·0) 0·56P. eff. 121 1 (0·8) 0 (0·0) 1 (0·8) 0·32 0 (0·0) 0 (0·0) 0 (0·0) 1·00AV leaflets thic. 111 23 (20·7) 17 (15·3) 19 (17·1) 0·30 1 (0·9) 0 (0·0) 0 (0·0) 0·32MV leaflets thic. 117 35 (29·9) 26 (22·2) 33 (28·2) 0·18 0 (0·0) 0 (0·0) 0 (0·0) 1·00Mitral an. calc. 116 7 (6·0) 7 (6·0) 6 (5·2) 1·00 0 (0·0) 0 (0·0) 0 (0·0) 1·00AV leaflets op. 111 4 (3·6) 4 (3·6) 0 (0·0) 1·00 4 (3·6) 4 (3·6) 2 (1·8) 1·00MV leaflets op. 117 2 (1·7) 2 (1·7) 0 (0·0) 1·00 2 (1·7) 2 (1·7) 0 (0·0) 1·00Wall motion ab. 196 24 (12·2) 17 (8·7) 15 (7·7) 0·26 0 (0·0) 0 (0·0) 0 (0·0) 0·66

Total 1732 248 (14·3) 185 (10·7) 206 (11·9) 0·001 24 (1·4) 21 (1·2) 10 (0·6) 0·64

n: number of data; SE: standard echocardiography; vs: versus; LV: left ventricular; RV: right ventricular; LA: left atrium; RA: rightatrium; P; eff.: pericardial effusion; AV: aortic valve; MV: mitral valve; Thic.: thickness; An.calc.: anulus calcification; Op.: opening; Ab.:abnormalities. P value is for comparison between hand-carried echo vs standard echo and inter-observer variability.



listed in Table 1. Most failed findings were pulmonicregurgitation (43 and 40, respectively). The reason forinadequate evaluation was suboptimal image quality(24 patients); incomplete videotape recordings duringfollow-up studies or limited studies (21 patients); andpresence of prosthetic valves (eight patients). A total of66/2253 (2·9%) findings were uninterpretable by thehand-carried device. The reason for inadequate evalu-ation was suboptimal image quality (29 patients); andpresence of prosthetic valves (eight patients). Thereforethe data analysis refers to the 2160/2253 (95·9%) findingsthat could be adequately evaluated by both the standardechocardiogram and the hand-carried device.

Image Quality

The mean value of image quality grades performed byreader B was not significantly different between thehand-carried device and standard echocardiograms: 1·54vs 1·50, respectively (P=NS). With the hand-carrieddevice, grade 1 or 2 image quality was reported in 98/121


patients (81·0%); grades 3 or 4 in 23/121 patients(19·0%). A side-by-side example of image qualitybetween the hand-carried device and standardechocardiography is shown in Figure 2.

Two-dimensional Data

For all 2D data, total differences (minor and major)between the hand-carried device and standard echo-cardiography were significantly higher than inter-observer variability on standard echocardiography: weobserved 248/1732 (14·3%) vs 185/1732 (10·7%) totaldifferences, respectively (P<0·05) (Table 1). Assessingeach individual 2D finding, total differences were signifi-cantly higher by the hand-carried device only for LV size(11·6% vs 4·1%, P<0·05), LV hypertrophy (32·2% vs18·2%, P<0·05) and right atrial size (22·3% vs 11·6%,P<0·05). However, major differences were not signifi-cantly higher by the hand-carried device for all 2D dataeither lumped together (1·4% vs 1·2%, respectively,P=NS) or for each individual finding.

Figure 2. Top: long axis parasternal view. Normal two-dimensional findings. (a) Standard echocardiography. (b)Hand-carried device. Bottom: apical five chamber view. Moderate to severe aortic regurgitation. (c) Standardechocardiography. (d) Hand-carried device. RV=right ventricle; LV=left ventricle; LA=left atrium; RA=rightatrium.


Three moderate to severe pathological findings weremissed with the hand-carried device. Two patients hadmoderately depressed LV function by standard echo-cardiography but were reported as having mildlydepressed function by OptiGo� and one patient withmoderate LV hypertrophy was reported by the hand-carried device examination as having normal wallthickness. Eleven normal findings on standard echo-cardiography were incorrectly called abnormal with thehand-carried device. Specifically, four cases with normalLV wall thickness were reported as having moderatehypertrophy; five cases with normal left atrial size andone case with normal right atrial size were reported ashaving moderately enlarged atria. One patient withnormal aortic valve leaflets was reported by the hand-carried device exam to have moderately thickened leaf-lets. According to these data, the hand-carried devicestudies had a sensitivity of 96·6% and a specificity of99·3% (Table 2).

Quantitative Linear Measurements

Quantitative linear measurements by standard echo-cardiography and by the hand-carried device examina-tions were not statistically different for left and rightatrial diameters (Table 3). The hand-carried devicemildly, but statistically significantly, overestimated LVend-diastolic diameter (mean value: 4·9 vs 4·8 cm,P<0·05).

Colour Doppler Data (ValvularRegurgitation)

The results before and after the upgrade of the colourDoppler were not statistically significantly different andwere therefore combined for final analysis.

For all colour Doppler data, total differences (minorand major) between the hand-carried device andstandard echocardiography were significantly higherthan the inter-observer variability of the two readers onstandard echocardiography: we observed 40·0% vs31·8% total differences respectively (P<0·007) (Table 4).However, major differences were not significantly higherby the hand-carried device (4·0% vs 2·6% respectively,PNS). For each individual colour Doppler finding, totaldifferences (minor and major), was significant for tri-cuspid regurgitation (P<0·03) and mitral regurgitation(P<0·05). For major differences alone, there was nosignificant grading difference.

We observed no major underestimation of regurgitantflow by the hand-carried device and no moderate tosevere regurgitation was missed with this device. On thecontrary, regurgitation in five cases were reported asmild by reader A on standard echocardiography butwere overestimated with the hand-carried device: twowere reported as moderate to severe (one aortic andone tricuspid regurgitation), and three were reportedas moderate (two mitral and one tricuspid regurgita-tion). These data represent a sensitivity for the

Table 2. Specificity and sensitivity of the hand-carrieddevice vs standard echocardiography. Moderate tosevere pathology.

Data Specificity Sensitivity

Two-dimensional 99·3% 96·6%Colour Doppler 98·5% 97·0%

Table 3. Linear measurements (mean values).

Data Hand-carrieddevice SE P

Left ventricularend-diastolic diameter

4·9�0·90 cm 4·8�0·93 cm 0·04

Left atrium diameter 5·9�0·95 cm 5·9�0·97 cm 0·28Right atrium diameter 5·2�0·83 cm 5·2�0·90 cm 0·21

SE: standard echocardiography.

Table 4. Accuracy of the hand-carried device for valve regurgitation.

Lesion n

% with difference % with major difference





AR 120 23·3 18·3 18·3 0·13 2·5 1·7 1·7 0·50MR 116 49·1 39·7 37·9 0·05 4·3 2·6 6·0 0·36TR 113 54·0 43·4 41·6 0·03 5·3 4·4 6·2 0·50PR 79 31·6 24·1 31·6 0·14 3·8 1·3 3·8 0·31

Total 428 40·0 31·8 32·2 0·007 4·0 2·6 4·4 0·151

n: number of data; SE: standard echocardiography; vs: versus; AR: aortic regurgitation; MR: mitral regurgitation; TR: tricuspidregurgitation; PR: pulmonic regurgitation. P value is for comparison between hand-carried echo vs standard echo and inter-observervariability.



hand-carried device exam of 97·0% and a specificity of98·5%, respectively (Table 2).

Discussion

Our study demonstrated OptiGo�’s overall imagequality is adequate in comparison to standard ‘top of theline’ echocardiography equipment for the focused evalu-ation performed in this study. Even though we couldclearly appreciate minor differences between OptiGo�

image data and the standard echocardiograph, clinicalaccuracy derived from the hand-carried device studiesproved to be acceptable.

Second, the ability of these devices to detect specificanatomic structures and grade pathological findings isessential. In this study, for 2D findings, although thetotal number of differences was significantly greater thancould be attributed to by inter-observer variability, thenumber of major differences between the hand-carrieddevice and the standard echocardiogram was not signifi-cant. Our data suggest that the accuracy of the hand-carried device is favourable when compared to standardechocardiography for the purpose of performing afocused examination of cardiac anatomy and functionand when performed by an echocardiographer with levelII training. This is indeed the intended use-model for thisdevice. The accuracy of the hand-carried device is sup-ported also by the specificity and high sensitivityobserved in the assessment of pathological findings.OptiGo� did overestimate LV wall thickness in fourpatients, LA size in five and RA size in one. The reasonfor the overestimation of cavity size is not clear but maybe due to a less well-defined myocardial wall to cavityecho interface on the miniaturized device, especially inthe far field.

A small but significant difference between quantitativelinear measurements using the hand-carried device andstandard echocardiography was observed only for LVend-diastolic diameter. Lack of an ECG tracing pre-vented accurate timing of standard end-diastolicmeasurements with the hand-carried device and may atleast in part be responsible for this discrepancy.

The results of the colour Doppler findings are particu-larly interesting, as this is the first generation of hand-carried devices equipped with this ultrasound modality.It is well recognized that ‘further evaluation of a mur-mur’ is a frequently asked question in referral for astandard echocardiogram[12]. OptiGo� overestimatedthe degree of regurgitation in five cases and although thehand-carried device differed from standard echo-cardiography regarding total findings, the number ofmajor differences was similar to the inter-observervariability.

Limitations

Most patients included in the study had normal or mildpathological findings, with moderate to severe pathology


accounting for only 6% of findings. However, this wasthe consequence of not selecting the patients beyondtheir consecutive appearance in the laboratory.

Reader B performed both the scanning and theinterpretation of all the hand-carried device examina-tions, whereas reader A interpreted the echocardiogramsperformed by sonographers. The high absolute qualityand standardization of the sonographers’ echocardio-grams and our study design probably make this a minorconsideration.

Reader B evaluated the standard echocardiograms ofthe same patients that he studied with the hand-carrieddevice, potentially leading to bias in reading of thestandard echocardiogram. However, reader B wasblinded to the patients’ identity when performing thereading of the standard echocardiograms. Further,the frequency of disagreement between the reading ofthe hand-carried echo by reader B and the reading of thestandard echo by reader B (intra-observer variability)closely approximates the inter-observer variability (seeTables 1 and 4). This supports the notion that thedisagreement between the hand-carried echo interpret-ation by reader B and the standard echo reading byreader A was not falsely reduced by the influence of thehand-carried echo reading by reader B on his reading ofthe standard echo.

We did not put a limit on the scanning time whenusing the hand-carried device but the scanning time of amean of 9·5 min was significantly shorter than that ofthe standard echocardiogram. The shorter scanning timeof the hand-carried device examinations may haveimpacted on its accuracy. It is premature to establish anoptimal scanning time for a limited bedside echocardio-gram and ultimately will depend on both the experienceof the examiner and on the clinical use of the device.

Conclusions and Further Studies

We have evaluated a new hand-carried cardiac ultra-sound device, which showed adequate image quality andaccuracy in identification of cardiac anatomy, functionand valvular regurgitation when used for a focusedexamination. The image quality combined with a prom-ising sensitivity for pathology suggests a potential rolefor the hand-carried device in augmenting the physicalexamination at the point-of-care, however the role ofsuch devices in the workflow of physicians is not yetestablished. The limitations imposed by trying to obtaina good quality study during a short examination timeare unknown. This is especially true among those with awide range of echocardiographic training and experi-ence. Finally, the low cost and easy operability of suchdevices provide the potential for widespread clinicalapplications, but also the risk that they are used byinadequately trained operators, potentially resulting innegative impact on patient care and on resource utiliz-ation. Future and extensive studies are needed to con-tinue the evaluation of these devices and to understandtheir appropriate applications in clinical practice.


AcknowledgementsDr Rugolotto was supported in part by the Mervin G. and

Roslyn G. Morris Fellowship at Stanford University School ofMedicine, Stanford, U.S.A.

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rapid assessment of cardiac anatomy and function with a new

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