Format

Send to

Choose Destination
J Magn Reson Imaging. 2016 Jun;43(6):1313-9. doi: 10.1002/jmri.25097. Epub 2015 Nov 19.

Simplified Bernoulli's method significantly underestimates pulmonary transvalvular pressure drop.

Author information

1
University of California Irvine, Department of Biomedical Engineering, Edwards Lifesciences Center of Advanced Cardiovascular Technology, Irvine, California, USA.
2
University Hospital Schleswig-Holstein Campus Kiel, Department of Pediatric Cardiology, Kiel, Germany.
3
Royal Brompton Hospital, London, UK, NIHR Cardiovascular Biomedical Research Unit of Royal Brompton and Harefield NHS Foundation Trust and Imperial College, London, UK.
4
Siemens Healthcare, Erlangen, Germany.

Abstract

PURPOSE:

To determine whether neglecting the flow unsteadiness in simplified Bernoulli's equation significantly affects the pulmonary transvalvular pressure drop estimation.

MATERIALS AND METHODS:

3.0T magnetic resonance imaging (MRI) 4D velocity mapping was performed on four healthy volunteers, seven patients with repaired tetralogy of Fallot, and thirteen patients with transposition of the great arteries repaired by arterial switch. Pulmonary transvalvular pressure drop was estimated based on two methods: General Bernoulli's Equation (GBE), ie, the most complete form; and Simplified Bernoulli's Equation (SBE), known as 4V(2) . More than 2300 individual pressure drop measurements were used to compare the simplified and the general Bernoulli's methods. A linear mixed-effects model was employed for statistical analyses, fully accounting for clustering of observations among the methods and systolic phases.

RESULTS:

The simplified Bernoulli's method systematically underestimated the pressure drop compared to general Bernoulli's method during the entire systolic phase (P < 0.05), including the peak systole, where on average ΔpSBE/ΔpGBE=78%.

CONCLUSION:

The simplified Bernoulli method underestimated the pressure drop during all systolic phases in all the studied subjects. Therefore, it is necessary to take into account the flow unsteadiness for more accurate estimation of the pressure drop. J. Magn. Reson. Imaging 2016;43:1313-1319.

KEYWORDS:

Bernoulli equation; pulmonary transvalvular pressure drop; pulmonary valve stenosis; unsteady Bernoulli equation

PMID:
26584006
DOI:
10.1002/jmri.25097
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Wiley Icon for eScholarship, California Digital Library, University of California
Loading ...
Support Center