Study Design
This prospective observational study was carried out between January
2018 to January 2020 at five outpatient sites within the Allina Health
system and the main outpatient site within the Minneapolis Heart
Institute Foundation. The study protocol was approved by the
Institutional Review Board (IRB), following which 180 consecutive
patients underwent echocardiographic assessment with the Vscan (GE
Medical Systems, Milwaukee, Wisconsin, USA) by 11 previously untrained
primary care providers.
The inclusion criteria were: (i) presence of at least one of the
following symptoms during a routine visit; shortness of breath or lack
of energy; or (ii) the presence of at least one of the following
clinical signs: edema or a new cardiac murmur on auscultation. There
were no exclusion criteria for patient enrollment.
All 11 primary care providers (including internists and advanced
practice providers such as physician assistants) were provided basic
instructions and self-directed learning tools on utilizing the Vscan
device, and were taught basic image acquisition for the following views:
Parasternal long/short axis as well as apical 3- and 4-chamber, and
given. The providers were also trained in utilizing the color Doppler
exam as needed. Prior to their participation in this study, the
providers’ experiences with handheld imaging devices varied from no to
minor experience.
Aortic stenosis was assessed using the parasternal long and short axis
views: a 2D assessment was performed to assess for leaflet mobility,
valve opening. Color Doppler acceleration in the left ventricular
outflow tract was added as necessary. Mitral and tricuspid regurgitation
was assessed using the parasternal long, apical 4-, and apical 3-
chamber views utilizing 2D assessment to identify leaflet coaptation and
color Doppler.
Patients underwent evaluation for VHD and LV function using the Vscan,
and all data were collected using a simple data collection sheet
(supplement 1). The providers recorded the following findings: (i)
Presence of Pericardial or Pleural Effusion, (ii) Presence of mild,
moderate or severe Aortic stenosis, Mitral regurgitation, and Tricuspid
regurgitation, (iii) LVEF using semi-quantitative analysis as normal
(EF>55%), mildly (EF>45 <55%),
moderately (EF <45 >35%) or severely (EF
<35%) reduced.
Following image acquisition by the outpatient provider, the patients’
echocardiographic Vscan images were read by 3 blinded expert
echocardiography readers and results reported on the same collection
sheets. Vscan devices for the study were provided through a research
grant by GE Healthcare.