title: Value of MR phase-contrast flow measurements for functional assessment of pulmonary arterial hypertension.
abstract: Goals of our study were to compare the pulmonary hemodynamics between healthy volunteers and patients with pulmonary arterial hypertension (PAH) and correlate MR flow measurements with echocardiography. Twenty-five patients with PAH and 25 volunteers were examined at 1.5 T. Phase-contrast flow measurements were performed in the ascending aorta and pulmonary trunk, resulting in the following parameters: peak velocity (cm/s), average blood flow (l/min), time to peak velocity (ms), velocity rise gradient and pulmonary distensibility (cm(2)). The bronchosystemic shunt was calculated. In PAH patients transthoracic echocardiography and right-heart catheterization (RHC) served as the gold standard. In comparison to volunteers, the PAH patients showed significantly reduced pulmonary velocities (P = 0.002), blood flow (P = 0.002) and pulmonary distensibility (P = 0.008). In patients, the time to peak velocity was shorter (P<0.001), and the velocity rise gradient was steeper (P = 0.002) than in volunteers. While in volunteers the peak velocity in the aorta was reached earlier, it was the reverse in patients. Patients showed a significant bronchosystemic shunt (P = 0.01). No meaningful correlation was found between MRI measurements and echocardiography or RHC. MRI is a feasible technique for the differentiation between PAH and volunteers. Further studies have to be conducted for the absolute calculation of pressure estimates.
authors.affiliation: Department of Radiology (E010), German Cancer Research Center DKFZ, Heidelberg, Germany. ley@gmx.net
authors.forename: Sebastian
authors.initials: S
authors.lastname: Ley
authors.forename: Derliz
authors.initials: D
authors.lastname: Mereles
authors.forename: Michael
authors.initials: M
authors.lastname: Puderbach
authors.forename: Ekkehard
authors.initials: E
authors.lastname: Gruenig
authors.forename: Helena
authors.initials: H
authors.lastname: Schöck
authors.forename: Monika
authors.initials: M
authors.lastname: Eichinger
authors.forename: Julia
authors.initials: J
authors.lastname: Ley-Zaporozhan
authors.forename: Christian
authors.initials: C
authors.lastname: Fink
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Kauczor
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology*; D006328:Cardiac Catheterization; D004452:Echocardiography; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis / Q000503:physiopathology*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008432:Mathematical Computing; D008875:Middle Aged; D011651:Pulmonary Artery / Q000503:physiopathology; D012680:Sensitivity and Specificity; D014664:Vasodilation / Q000502:physiology