TY - JOUR

T1 - Non-Invasive Assessment of Intravascular Pressure Gradients

T2 - A Review of Current and Proposed Novel Methods

AU - Nguyen, Tin-Quoc

AU - Hansen, Kristoffer Lindskov

AU - Bechsgaard, Thor

AU - Lonn, Lars

AU - Jensen, Jørgen Arendt

AU - Nielsen, Michael Bachmann

N1 - This article belongs to the Special Issue Imaging-Based Diagnostics in Interventional Medicine

PY - 2019

Y1 - 2019

N2 - Invasive catheterization is associated with a low risk of serious complications. However, although it is the gold standard for measuring pressure gradients, it induces changes to blood flow and requires significant resources. Therefore, non-invasive alternatives are urgently needed. Pressure gradients are routinely estimated non-invasively in clinical settings using ultrasound and calculated with the simplified Bernoulli equation, a method with several limitations. A PubMed literature search on validation of non-invasive techniques was conducted, and studies were included if non-invasively estimated pressure gradients were compared with invasively measured pressure gradients in vivo. Pressure gradients were mainly estimated from velocities obtained with Doppler ultrasound or magnetic resonance imaging. Most studies used the simplified Bernoulli equation, but more recent studies have employed the expanded Bernoulli and Navier–Stokes equations. Overall, the studies reported good correlation between non-invasive estimation of pressure gradients and catheterization. Despite having strong correlations, several studies reported the non-invasive techniques to either overestimate or underestimate the invasive measurements, thus questioning the accuracy of the non-invasive methods. In conclusion, more advanced imaging techniques may be needed to overcome the shortcomings of current methods

AB - Invasive catheterization is associated with a low risk of serious complications. However, although it is the gold standard for measuring pressure gradients, it induces changes to blood flow and requires significant resources. Therefore, non-invasive alternatives are urgently needed. Pressure gradients are routinely estimated non-invasively in clinical settings using ultrasound and calculated with the simplified Bernoulli equation, a method with several limitations. A PubMed literature search on validation of non-invasive techniques was conducted, and studies were included if non-invasively estimated pressure gradients were compared with invasively measured pressure gradients in vivo. Pressure gradients were mainly estimated from velocities obtained with Doppler ultrasound or magnetic resonance imaging. Most studies used the simplified Bernoulli equation, but more recent studies have employed the expanded Bernoulli and Navier–Stokes equations. Overall, the studies reported good correlation between non-invasive estimation of pressure gradients and catheterization. Despite having strong correlations, several studies reported the non-invasive techniques to either overestimate or underestimate the invasive measurements, thus questioning the accuracy of the non-invasive methods. In conclusion, more advanced imaging techniques may be needed to overcome the shortcomings of current methods

KW - pressure gradient

KW - ultrasound

KW - magnetic resonance imaging

KW - intravascular catheterization

KW - review

U2 - 10.3390/diagnostics9010005

DO - 10.3390/diagnostics9010005

M3 - Review

C2 - 30597993

VL - 9

JO - Diagnostics

JF - Diagnostics

SN - 2075-4418

IS - 1

M1 - 5

ER -