Magnetic resonance imaging guided catheterisation for assessment of pulmonary vascular resistance: in vivo validation and clinical application in patients with pulmonary hypertension. Issue 8 (14th July 2005)

• Record Type: Journal Article
• Authors: Kuehne, T; Yilmaz, S; Schulze-Neick, I; Wellnhofer, E; Ewert, P; Nagel, E; Lange, P
• Is Part Of: Heart. Volume 91:Issue 8(2005)
• Page Start: 1064
• Page End: 1069
• Publication Date: 2005-07-14
• Subjects: LA, left atrial -- MRI, magnetic resonance imaging -- PA, pulmonary artery -- PHT, pulmonary hypertension -- PVR, pulmonary vascular resistance -- VEC, velocity encoded cine; congenital heart disease -- magnetic resonance imaging -- pulmonary hypertension; Heart -- Diseases -- Treatment -- Periodicals; Cardiology -- Periodicals; 616.12
• DOI: 10.1136/hrt.2004.038265
• Languages: English
• ISSNs: 1355-6037

Abstract

Abstract : Objectives: To validate in vivo a magnetic resonance imaging (MRI) method for measurement of pulmonary vascular resistance (PVR) and subsequently to apply this technique to patients with pulmonary hypertension (PHT). Methods and results: PVR was assessed from velocity encoded cine MRI derived pulmonary artery (PA) flow volumes and simultaneously determined invasive PA pressures. For pressure measurements flow directed catheters were guided under magnetic resonance fluoroscopy at 1.5 T into the PA. In preliminary validation studies (eight swine) PVR was determined with the thermodilution technique and compared with PVR obtained by MRI (0.9 (0.5) v 1.1 (0.3) Wood units·m 2, p = 0.7). Bland-Altman test showed agreement between both methods. Inter-examination variability was high for thermodilution (6.2 (2.2)%) but low for MRI measurements (2.1 (0.3)%). After validation, the MRI method was applied in 10 patients with PHT and five controls. In patients with PHT PVR was measured at baseline and during inhalation of nitric oxide. Compared with the control group, PVR was significantly increased in the PHT group (1.2 (0.8) v 13.1 (5.6) Wood units·m 2, p < 0.001) but decreased significantly to 10.3 (4.6) Wood units·m 2 during inhalation of nitric oxide (p < 0.05). Inter-examination variability of MRI derived PVR measurements was 2.6 (0.6)%. In all experiments (in vivo and clinical) flow directed catheters were guided successfully into the PA under MRI control. Conclusions: Guidance of flow directed catheters into the PA is feasible under MRI control. PVR can be determined with high measurement precision with the proposed MRI technique, which is a promising tool to assess PVR in the clinical setting.