TY - JOUR
T1 - Vector Flow Imaging Compared with Conventional Doppler Ultrasound and Thermodilution for Estimation of Blood Flow in the Ascending Aorta
AU - Hansen, Kristoffer Lindskov
AU - Møller-Sørensen, Hasse
AU - Kjaergaard, Jesper
AU - Jensen, Maiken Brit
AU - Lund, Jens Teglgaard
AU - Pedersen, Mads Møller
AU - Olesen, Jacob Bjerring
AU - Jensen, Jørgen Arendt
AU - Bachmann Nielsen, Michael
PY - 2017
Y1 - 2017
N2 - Transverse oscillation (TO) is a real-time ultrasound vector flow method implemented on a
commercial scanner. The TO setup was examined on a flowrig with constant and pulsatile flow.
Subsequently, 25 patients undergoing cardiac bypass surgery were scanned intraoperatively with
TO on the ascending aorta and compared to transesophageal echocardiography (TEE) and
pulmonary artery catheter thermodilution (PACTD). On the flowrig, TO had a precision of
5.5%, 9.4% and 14.7%, a percentage error of 18.2%, 14.6% and 40.7%, and a mean bias of 0.4
cm/s, 36.8 ml/min and 32.4 ml/min for velocity and flow rate (constant and pulsatile) estimation.
The correlation coefficients for all flowrig evaluations were 0.99 indicating systematic bias. After
bias correction, the percentage error was reduced to 11.5%, 12.6% and 15.9% for velocity and
flow rate (constant and pulsatile) estimation. In the in vivo setup, TO, TEE, and PACTD had
a precision of 21.9%, 13.7%, and 12.0%. TO compared with TEE and PACTD had a mean bias
of 12.6 cm/s and –0.08 l/min, and a percentage error of 23.4%, and 36.7%, respectively. The
percentage error was reduced to 22.9% for the TEE comparison, but increased to 43.8% for
the PACTD comparison, after correction for the systematic bias found in the flowrig. TO is a
reliable and precise method for velocity and flow rate estimation on a flowrig. However, TO
with the present setup, is not interchangeable with PACTD for cardiac volume flow estimation,
but is a reliable and precise angle-independent ultrasound alternative for velocity estimation of
cardiac flow.
AB - Transverse oscillation (TO) is a real-time ultrasound vector flow method implemented on a
commercial scanner. The TO setup was examined on a flowrig with constant and pulsatile flow.
Subsequently, 25 patients undergoing cardiac bypass surgery were scanned intraoperatively with
TO on the ascending aorta and compared to transesophageal echocardiography (TEE) and
pulmonary artery catheter thermodilution (PACTD). On the flowrig, TO had a precision of
5.5%, 9.4% and 14.7%, a percentage error of 18.2%, 14.6% and 40.7%, and a mean bias of 0.4
cm/s, 36.8 ml/min and 32.4 ml/min for velocity and flow rate (constant and pulsatile) estimation.
The correlation coefficients for all flowrig evaluations were 0.99 indicating systematic bias. After
bias correction, the percentage error was reduced to 11.5%, 12.6% and 15.9% for velocity and
flow rate (constant and pulsatile) estimation. In the in vivo setup, TO, TEE, and PACTD had
a precision of 21.9%, 13.7%, and 12.0%. TO compared with TEE and PACTD had a mean bias
of 12.6 cm/s and –0.08 l/min, and a percentage error of 23.4%, and 36.7%, respectively. The
percentage error was reduced to 22.9% for the TEE comparison, but increased to 43.8% for
the PACTD comparison, after correction for the systematic bias found in the flowrig. TO is a
reliable and precise method for velocity and flow rate estimation on a flowrig. However, TO
with the present setup, is not interchangeable with PACTD for cardiac volume flow estimation,
but is a reliable and precise angle-independent ultrasound alternative for velocity estimation of
cardiac flow.
KW - Vector flow imaging
KW - Transverse oscillation
KW - Flowrig
KW - Intraoperative cardiac ultrasound
KW - Ascending aorta
U2 - 10.1177/0161734615620137
DO - 10.1177/0161734615620137
M3 - Journal article
C2 - 26705136
SN - 0161-7346
VL - 39
SP - 3
EP - 18
JO - Ultrasonic Imaging
JF - Ultrasonic Imaging
IS - 1
ER -