Munenobu Nogami MD, PhD, Presenter: Nothing to Disclose

Yoshiharu Ohno MD, PhD, Abstract Co-Author: Nothing to Disclose

Atsushi Kono MD, Abstract Co-Author: Nothing to Disclose

Hisanobu Koyama MD, Abstract Co-Author: Nothing to Disclose

Daisuke Takenaka MD, Abstract Co-Author: Nothing to Disclose

Kazuro Sugimura MD, Abstract Co-Author: Nothing to Disclose

Yumiko Onishi MD, Abstract Co-Author: Nothing to Disclose

Masahiko Fujii MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

To compare the utility of phase contrast MR imaging (PC-MRI) with that of echocardiography (cardiac US) and right heart catheterization for assessment of disease severity of pulmonary hypertension in terms of flow and pressure estimation.

64 consecutive patients (37 males and 27 females; mean age, 68.4 years) with suspected pulmonary hypertension underwent PC-MRI and cardiac US. In addition, right heart catheterization was performed for 11 out of 64 patients. All PC-MRIs were acquired by cine 2D phase contrast method with parallel imaging on a 1.5 T scanner. Images were obtained in the perpendicular sections to the main pulmonary artery and tricuspid valve determined by cine balanced FFE images at horizontal and vertical long axes. For flow measurements, stroke volume (SV) through the main pulmonary artery was calculated from area under the curve of time-velocity curve by PC-MRI, and the velocity time integral by cardiac US. For pressure estimation, maximal velocity of the tricuspid regurgitation during systole was measured by PC-MRI and cardiac US, and pulmonary arterial systolic pressure (PASP) was estimated based on the modified Bernoulli's equation. To determine the utility of PC-MRI for disease severity assessment of pulmonary hypertension in terms of flow and pressure estimation, the limits of agreement of SV and PASP among PC-MRI, cardiac US and catheterization were assessed by the Bland and Altman’s analysis.

The limits of agreement for SV between PC-MRI and cardiac US (2.7 ± 33.4 ml) were larger than those between PC-MRI and catheterization (1.2 ± 2.3 ml). The limits of agreement for PASP between PC-MRI and cardiac US (-2.8 ± 12.4 mmHg) were also larger than those between PC-MRI and catheterization (-5.7 ± 4.2 mmHg).

Phase contrast MR imaging is more accurate than cardiac US in pulmonary flow and pressure estimation according to the catheterization data, and may be useful for assessment of disease severity in pulmonary hypertension patients.

Phase contrast MRI is useful for noninvasive estimation of pulmonary arterial flow and pressure, and may have an important role for management of patients with pulmonary hypertension.

Nogami, M, Ohno, Y, Kono, A, Koyama, H, Takenaka, D, Sugimura, K, Onishi, Y, Fujii, M, et al, , et al, , Utility of Phase Contrast MR Imaging for Assessment of Disease Severity in Patients with Pulmonary Hypertension: Comparison with Echocardiography and Right Heart Catheterization.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5012266.html