OBJECTIVE: The purpose of this study was to use phase-contrast MRI to evaluate the influence of various breathing maneuvers on the hemodynamics of the pulmonary and systemic arterial circulation. SUBJECTS AND METHODS: Twenty-five volunteers were examined with phase-contrast MRI. Flow measurements were acquired in the aorta, pulmonary trunk, and left and right pulmonary arteries during deep, large-volume inspiratory breath-hold, expiratory breath-hold, and smooth respiration (no breath-hold). Parameters assessed were peak velocity, blood flow, velocity gradient, and acceleration time. RESULTS: Pulmonary blood flow and peak velocity were significantly reduced during inspiratory breath-hold and expiratory breath-hold compared with no breath-hold (p < 0.01). Pulmonary velocity gradient in inspiratory breath-hold was significantly (p </= 0.01) lower than in expiratory breath-hold and no breath-hold. There was no difference in velocity gradient between expiratory breath-hold and no breath-hold. Peak velocity in the aorta was lowest with no breath-hold. Velocity gradient was highest in expiratory breath-hold, and no breath-hold had the smallest SD. Acceleration time in the pulmonary trunk showed no difference between inspiratory breath-hold, expiratory breath-hold, and no breath-hold. Blood flow distribution to the left (45-47%) and to the right (53-55%) lung was not influenced by breathing maneuver. CONCLUSION: Measurements during smooth respiration showed the smallest SD. Therefore, no-breath-hold measurements should be considered for assessment of hemodynamics in clinical practice.
OBJECTIVE: The purpose of this study was to use phase-contrast MRI to evaluate the influence of various breathing maneuvers on the hemodynamics of the pulmonary and systemic arterial circulation. SUBJECTS AND METHODS: Twenty-five volunteers were examined with phase-contrast MRI. Flow measurements were acquired in the aorta, pulmonary trunk, and left and right pulmonary arteries during deep, large-volume inspiratory breath-hold, expiratory breath-hold, and smooth respiration (no breath-hold). Parameters assessed were peak velocity, blood flow, velocity gradient, and acceleration time. RESULTS: Pulmonary blood flow and peak velocity were significantly reduced during inspiratory breath-hold and expiratory breath-hold compared with no breath-hold (p < 0.01). Pulmonary velocity gradient in inspiratory breath-hold was significantly (p </= 0.01) lower than in expiratory breath-hold and no breath-hold. There was no difference in velocity gradient between expiratory breath-hold and no breath-hold. Peak velocity in the aorta was lowest with no breath-hold. Velocity gradient was highest in expiratory breath-hold, and no breath-hold had the smallest SD. Acceleration time in the pulmonary trunk showed no difference between inspiratory breath-hold, expiratory breath-hold, and no breath-hold. Blood flow distribution to the left (45-47%) and to the right (53-55%) lung was not influenced by breathing maneuver. CONCLUSION: Measurements during smooth respiration showed the smallest SD. Therefore, no-breath-hold measurements should be considered for assessment of hemodynamics in clinical practice.
Authors: Michael A Bolen; Randolph M Setser; Ruvin S Gabriel; Rahul D Renapurkar; Yasmeen Tandon; Michael L Lieber; Milind Y Desai; Scott D Flamm Journal: Int J Cardiovasc Imaging Date: 2012-04-22 Impact factor: 2.357
Authors: Laura C Bell; Kang Wang; Alejandro Munoz Del Rio; Thomas M Grist; Sean B Fain; Scott K Nagle Journal: Invest Radiol Date: 2015-03 Impact factor: 6.016
Authors: Michael J Rose; Kelly Jarvis; Varun Chowdhary; Alex J Barker; Bradley D Allen; Joshua D Robinson; Michael Markl; Cynthia K Rigsby; Susanne Schnell Journal: J Magn Reson Imaging Date: 2016-05-18 Impact factor: 4.813