Evaluation of hemodynamic changes by use of phase-contrast MRI for patients with interstitial pneumonia, with special focus on blood flow reduction after breath-holding and bronchopulmonary shunt flow

Abstract

The purpose of this study was to determine the effects of interstitial pneumonia on pulmonary, systemic, and bronchopulmonary shunt flow. Phase-contrast flow measurements in the ascending aorta and pulmonary trunk were performed during free breathing and inspiratory breath-holding by use of a 1.5 T MR scanner. The study population comprised 11 patients with interstitial pneumonia and 15 healthy volunteers. Absolute blood flow, bronchopulmonary shunt flow, and difference in flow between normal breathing and breath-holding were compared between the groups. Both pulmonary and systemic blood flow during both breathing patterns in patients were significantly reduced compared with the volunteers (p < 0.05). However, bronchopulmonary shunt flow and reduction of systemic and pulmonary artery flow did not differ between groups. Interstitial pneumonia reduces both pulmonary and systemic blood flow, but it does not affect the amount of flow reduction during breath-holding. The bronchopulmonary shunt was not increased in interstitial pneumonia patients, probably because of stiffness of the bronchial arteries.