Evaluation of Pulmonary Artery Stiffness in Pulmonary Hypertension With Cardiac Magnetic Resonance
Author + information
- Received June 6, 2008
- Revision received August 4, 2008
- Accepted August 20, 2008
- Published online March 1, 2009.
Author Information
- Javier Sanz, MD⁎,⁎ (Javier.Sanz{at}mssm.edu),
- Mbabazi Kariisa, MPH⁎,†,
- Santo Dellegrottaglie, MD, PhD⁎,‡,
- Susanna Prat-González, MD⁎,
- Mario J. Garcia, MD, FACC⁎,
- Valentin Fuster, MD, PhD, FACC⁎ and
- Sanjay Rajagopalan, MD, FACC⁎,†
- ↵⁎Reprint requests and correspondence:
Dr. Javier Sanz, Clinical Cardiac MR/CT Program, Cardiovascular Institute, Mount Sinai Hospital, One Gustave L. Levy Place, Box 1030, New York, New York 10029
Abstract
Objectives This study sought to evaluate indexes of pulmonary artery (PA) stiffness in patients with pulmonary hypertension (PH) using same-day cardiac magnetic resonance (CMR) and right heart catheterization (RHC).
Background Pulmonary artery stiffness is increased in the presence of PH, although the relationship to PH severity has not been fully characterized.
Methods Both CMR and RHC were performed on the same day in 94 patients with known or suspected PH. According to the RHC, patients were classified as having no PH (n = 13), exercise-induced PH (EIPH) only (n = 6), or PH at rest (n = 75). On CMR, phase-contrast images were obtained perpendicular to the pulmonary trunk. From CMR and RHC data, PA areas and indexes of stiffness (pulsatility, compliance, capacitance, distensibility, elastic modulus, and the pressure-independent stiffness index β) were measured at rest.
Results All quantified indexes showed increased PA stiffness in patients with PH at rest in comparison with those with EIPH or no PH. Despite the absence of significant differences in baseline pressures, patients with EIPH had lower median compliance and capacitance than patients with no PH: 15 (interquartile range: 9 to 19.8) mm2/mm Hg versus 8.4 (interquartile range: 6 to 10.3) mm2/mm Hg, and 5.2 (interquartile range: 4.4 to 6.3) mm3/mm Hg versus 3.7 (interquartile range: 3.1 to 4.1) mm3/mm Hg, respectively (p < 0.05). The different measurements of PA stiffness, including stiffness index β, showed significant correlations with PA pressures (r2 = 0.27 to 0.73). Reduced PA pulsatility (<40%) detected the presence of PH at rest with a sensitivity of 93% and a specificity of 63%.
Conclusions Pulmonary artery stiffness increases early in the course of PH (even when PH is detectable only with exercise and before overt pressure elevations occur at rest). These observations suggest a potential contributory role of PA stiffness in the development and progression of PH.
Footnotes
Dr. Prat-González is supported by a grant from Fundación CajaMadrid.
- Received June 6, 2008.
- Revision received August 4, 2008.
- Accepted August 20, 2008.
- American College of Cardiology Foundation