Simplified Bernoulli's method significantly underestimates pulmonary transvalvular pressure drop

Falahatpisheh, Ahmad; Rickers, Carsten; Gabbert, Dominik Daniel; Heng, Ee Ling; Stalder, Aurélien F.; Kramer, Hans‐Heiner; Kilner, Philip J.; Kheradvar, Arash

doi:10.1002/jmri.25097

Cited by 24 publications

(17 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, the true pressure drop and the predicted pressure drop, based on the simplified Bernoulli method are not directly interchangeable. The discrepancy between the simplified Bernoulli estimation and the true pressure drop has frequently been reported . Therefore, it functions as a relative metric for clinical cut‐off rather than a true pressure prediction .…”

Section: Discussionmentioning

confidence: 99%

“…The discrepancy between the simplified Bernoulli estimation and the true pressure drop has frequently been reported. [5][6][7][8]11 Therefore, it functions as a relative metric for clinical cut-off rather than a true pressure prediction. 33 Considering the significant amount of clinical data that have been obtained with the simplified Bernoulli method, further methods to make the various pressure estimations interchangeable would be an important issue to investigate in the future.…”

Section: F I G U R E 5 Comparison Of 4d Flow Mri Pressure Drop Estimamentioning

confidence: 99%

“…3 Time-resolved, threedirectional, and 3D phase-contrast MRI (that is commonly abbreviated as 4D PC-MRI or 4D flow MRI) has recently been developed, and clinical applications of 4D flow MRI for the assessment of pressure drop have been demonstrated based on the method's non-invasive and multi-dimensional velocity assessment. 4,5 Despite that the Bernoulli method provides various advantages for pressure drop estimation, discrepancies between Bernoulli-based prediction and invasive pressure measurement are frequently observed because of its inherent underestimation of pressure recovery in the post-stenotic region. [6][7][8][9] This fact has triggered the necessity for the development of different types of pressure drop estimation that validate and complement the conventional Bernoulli method.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Validation of pressure drop assessment using 4D flow MRI‐based turbulence production in various shapes of aortic stenoses

Kvitting

Dyverfeldt

et al. 2018

Magnetic Resonance in Med

View full text Add to dashboard Cite

Purpose To validate pressure drop measurements using 4D flow MRI‐based turbulence production in various shapes of stenotic stenoses. Methods In vitro flow phantoms with seven different 3D‐printed aortic valve geometries were constructed and scanned with 4D flow MRI with six‐directional flow encoding (ICOSA6). The pressure drop through the valve was non‐invasively predicted based on the simplified Bernoulli, the extended Bernoulli, the turbulence production, and the shear‐scaling methods. Linear regression and agreement of the predictions with invasively measured pressure drop were analyzed. Results All pressure drop predictions using 4D Flow MRI were linearly correlated to the true pressure drop but resulted in different regression slopes. The regression slope and 95% limits of agreement for the simplified Bernoulli method were 1.35 and 11.99 ± 21.72 mm Hg. The regression slope and 95% limits of agreement for the extended Bernoulli method were 1.02 and 0.74 ± 8.48 mm Hg. The regression slope and 95% limits of agreement for the turbulence production method were 0.89 and 0.96 ± 8.01 mm Hg. The shear‐scaling method presented good correlation with an invasively measured pressure drop, but the regression slope varied between 0.36 and 1.00 depending on the shear‐scaling coefficient. Conclusion The pressure drop assessment based on the turbulence production method agrees well with the extended Bernoulli method and invasively measured pressure drop in various shapes of the aortic valve. Turbulence‐based pressure drop estimation can, as a complement to the conventional Bernoulli method, play a role in the assessment of valve diseases.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: F I G U R E 5 Comparison Of 4d Flow Mri Pressure Drop Estimamentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Validation of pressure drop assessment using 4D flow MRI‐based turbulence production in various shapes of aortic stenoses

Kvitting

Dyverfeldt

et al. 2018

Magnetic Resonance in Med

View full text Add to dashboard Cite

show abstract

“…Based on the assumption of inviscid flow and the ideal energy conversion between kinetic energy and pressure, the simplified Bernoulli equation can overestimate the true irreversible pressure loss by neglecting pressure recovery in the post-stenotic region9. In addition, it can underestimate the true pressure difference by not accounting for flow unsteadiness, such as acceleration of the blood flow10. Several studies have proposed modified versions of the simplified Bernoulli equation by adding corrective terms.…”

mentioning

confidence: 99%

“…For example, the inclusion of a ratio between the effective aortic orifice area (EOA) and the aortic cross-sectional area to the simplified Bernoulli equation was presented based on the concept of fluid-dynamic energy loss through a sudden expansion, and it has shown the potential to reflect the pressure recovery in the post-stenosis region11. Parallel research on the Generalized Bernoulli equation suggested that the accuracy of the pressure drop estimation can be improved by including an acceleration term along a flow streamline upstream and downstream of the stenotic vessel10. However, the accuracy of the irreversible pressure drop estimation based on the Bernoulli equation in various pathological conditions remains uncertain12131415.…”

mentioning

confidence: 99%

Estimating the irreversible pressure drop across a stenosis by quantifying turbulence production using 4D Flow MRI

Lantz

Ziegler

et al. 2017

Sci Rep

View full text Add to dashboard Cite

The pressure drop across a stenotic vessel is an important parameter in medicine, providing a commonly used and intuitive metric for evaluating the severity of the stenosis. However, non-invasive estimation of the pressure drop under pathological conditions has remained difficult. This study demonstrates a novel method to quantify the irreversible pressure drop across a stenosis using 4D Flow MRI by calculating the total turbulence production of the flow. Simulation MRI acquisitions showed that the energy lost to turbulence production can be accurately quantified with 4D Flow MRI within a range of practical spatial resolutions (1–3 mm; regression slope = 0.91, R2 = 0.96). The quantification of the turbulence production was not substantially influenced by the signal-to-noise ratio (SNR), resulting in less than 2% mean bias at SNR > 10. Pressure drop estimation based on turbulence production robustly predicted the irreversible pressure drop, regardless of the stenosis severity and post-stenosis dilatation (regression slope = 0.956, R2 = 0.96). In vitro validation of the technique in a 75% stenosis channel confirmed that pressure drop prediction based on the turbulence production agreed with the measured pressure drop (regression slope = 1.15, R2 = 0.999, Bland-Altman agreement = 0.75 ± 3.93 mmHg).

show abstract

Comments regarding “Simplified Bernoulli's method significantly underestimates pulmonary transvalvular pressure drop”

Karvandi

2016

Magnetic Resonance Imaging

View full text Add to dashboard Cite

I have read carefully the recent article by Falahatpisheh et al. 1 I am grateful to the authors for their comprehensive and very sensible research of recent studies on the simplified Bernoulli equation (SBE), significantly underestimates pulmonary transvalvular pressure drop, utilizing 3.0T magnetic resonance imaging (MRI) 4D velocity mapping in 3D and time, to quantify the velocity field in the vicinity behind of the pulmonary valve and estimate the pressure drop by the general Bernoulli equation (GBE). Accordingly, Falahatpisheh et al 1 first used 4D-flow MRI to track the pattern of the flow-dependent phase for normal subjects and patients with repaired congenital heart defects. The pixel values of the velocity images were converted to physical velocity. The pressure drop through the pulmonary valve was approximated based on GBE and SBE, known as 4V 2 . In the GBE, the unsteady term comprises the integral of the derivative of velocity with respect to time over a flow streamline between the upstream and downstream velocity points were added. The results of their study show that the SBE method significantly underestimated the pressure drop compared to the GBE method during the entire systolic phase, including the peak systole. This difference may result in confusing circumstances for grading the stenosis when the pressure drop is within a doubtful range. With regard to the issue of pulmonary valve stenosis (PS), my take is that, just as in the case of other heart lesions, it is all a matter of "convention" and "correlation": that is, it is not important (any more) how accurate we are in the estimation of a certain parameter as long as we all have a common understanding of what it means and we have a clear correlation with known outcomes. In other words, it is not important if a right ventricular pressure pulmonary arterial (RV-PA) gradient is 80 mmHg or 60 or 40 (as these differences may very well depend on the method of measurement and the status of the patient: sedated/agitated); what is important is that we all have the same understanding of what it means to the patient (clinically) in the long and short run.That On the other hand, in the setting of a child with aortic stenosis (AS) and coarctation of the aorta, both lesions "collude" to underestimate each other's severity by decreasing the gradient across the obstruction. Therefore, we do not know if we need to balloon the aortic valve or the coarctation or both. Here I am sure that there may be a role for the GBE in accurately estimating the severity.To conclude, there would be a huge clinical advantage to developing a noninvasive measure of stenosis.

show abstract

Simplified Bernoulli's method significantly underestimates pulmonary transvalvular pressure drop

Cited by 24 publications

References 38 publications

Validation of pressure drop assessment using 4D flow MRI‐based turbulence production in various shapes of aortic stenoses

Validation of pressure drop assessment using 4D flow MRI‐based turbulence production in various shapes of aortic stenoses

Estimating the irreversible pressure drop across a stenosis by quantifying turbulence production using 4D Flow MRI

Comments regarding “Simplified Bernoulli's method significantly underestimates pulmonary transvalvular pressure drop”

Contact Info

Product

Resources

About