Skip to main content
eScholarship
Open Access Publications from the University of California

UC San Diego

UC San Diego Previously Published Works bannerUC San Diego

Real-time magnetic resonance imaging technique for determining left ventricle pressure-volume loops.

  • Author(s): Witschey, Walter RT;
  • Contijoch, Francisco;
  • McGarvey, Jeremy R;
  • Ferrari, Victor A;
  • Hansen, Michael S;
  • Lee, Madonna E;
  • Takebayashi, Satoshi;
  • Aoki, Chikashi;
  • Chirinos, Julio A;
  • Yushkevich, Paul A;
  • Gorman, Joseph H;
  • Pilla, James J;
  • Gorman, Robert C
  • et al.

Published Web Location

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3939798/pdf/nihms556919.pdf
No data is associated with this publication.
Abstract

Background

Rapid determination of the left ventricular (LV) pressure-volume (PV) relationship as loading conditions are varied is the gold standard for assessment of LV function. Cine magnetic resonance imaging (MRI) does not have sufficient spatiotemporal resolution to assess beat-to-beat changes of the LV PV relationship required to measure the LV end-systolic elastance (EES) or preload-recruitable stroke work (PRSW). Our aim was to investigate real-time MRI and semiautomated LV measurement of LV volume to measure PV relations in large animals under normal and inotropically stressed physiologic conditions.

Methods

We determined that PV relationships could be accurately measured using an image exposure time Tex less than 100 ms and frame rate Tfr less than 50 ms at elevated heart rates (∼140 beats per minute) using a golden angle radial MRI k-space trajectory and active contour segmentation.

Results

With an optimized exposure time (Tex=95 ms and frame rate Tfr=2.8 ms), we found that there was no significant difference between cine and real-time MRI at rest in end-diastolic volume, end-systolic volume, ejection fraction, stroke volume, or cardiac output (n=5, p<0.05) at either normal or elevated heart rates. We found EES increased from 1.9±0.7 to 3.1±0.3 mm Hg/mL and PRSW increased from 6.2±1.2 to 9.1±0.9 mm Hg during continuous intravenous dobutamine infusion (n=5, p<0.05).

Conclusions

Real-time MRI can assess LV volumes, EES, and PRSW at baseline and elevated inotropic states.

Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.

Item not freely available? Link broken?
Report a problem accessing this item