Note: This copy is for your personal, non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, contact us at www.rsna.org/rsnarights. ORIGINAL RESEARCH n CARDIAC IMAGING Radiology: Volume 258: Number 1—January 2011 n radiology.rsna.org 119 Right and Left Ventricular Myocardial Perfusion Reserves Correlate with Right Ventricular Function and Pulmonary Hemodynamics in Patients with Pulmonary Arterial Hypertension 1 Jens Vogel-Claussen, MD Jan Skrok, MD Monda L. Shehata, MD Sukhminder Singh, MD Christopher T. Sibley, MD Danielle M. Boyce, MPH Noah Lechtzin, MD, MHS Reda E. Girgis, MD Steven C. Mathai, MD, MHS Thomas A. Goldstein, PhD Jie Zheng, PhD João A. C. Lima, MD David A. Bluemke, MD, PhD Paul M. Hassoun, MD Purpose: To evaluate the relationships of right ventricular (RV) and left ventricular (LV) myocardial perfusion reserves with ventricu- lar function and pulmonary hemodynamics in patients with pulmonary arterial hypertension (PAH) by using adenosine stress perfusion cardiac magnetic resonance (MR) imaging. Materials and Methods: This HIPAA-compliant study was institutional review board approved. Twenty-five patients known or suspected to have PAH underwent right heart catheterization and adenosine stress MR imaging on the same day. Sixteen matched healthy control subjects underwent cardiac MR imaging only. RV and LV perfusion values at rest and at adenosine-induced stress were calculated by using the Fermi function model. The MR imaging–derived RV and LV functional data were calculated by using dedicated software. Statistical testing included Kruskal- Wallis tests for continuous data, Spearman rank correlation tests, and multiple linear regression analyses. Results: Seventeen of the 25 patients had PAH: 11 with scleroderma- associated PAH, and six with idiopathic PAH. The remaining eight patients had scleroderma without PAH. The myocardial perfusion reserve indexes (MPRIs) in the PAH group (median RV MPRI, 1.7 [25th–75th percentile range, 1.3–2.0]; median LV MPRI, 1.8 [25th–75th percentile range, 1.6–2.1]) were significantly lower than those in the scleroderma non-PAH (median RV MPRI, 2.5 [25th–75th percentile range, 1.8–3.9] [ P = .03]; median LV MPRI, 4.1 [25th–75th percentile range, 2.6–4.8] [ P = .0003]) and control (median RV MPRI, 2.9 [25th–75th percentile range, 2.6–3.6] [ P , .01]; median LV MPRI, 3.6 [25th–75th percentile range, 2.7–4.1] [ P , .01]) groups. There were significant correlations between biven- tricular MPRI and both mean pulmonary arterial pressure (mPAP) (RV MPRI: r = 20.59, Bonferroni P = .036; LV MPRI: r = 20.79, Bonferroni P , .002) and RV stroke work index (RV MPRI: r = 20.63, Bonferroni P = .01; LV MPRI: r = 20.75, Bonferroni P , .002). In linear regression analysis, mPAP and RV ejection fraction were independent predictors of RV MPRI. mPAP was an independent predictor of LV MPRI. Conclusion: Biventricular vasoreactivity is significantly reduced with PAH and inversely correlated with RV workload and ejection frac- tion, suggesting that reduced myocardial perfusion reserve may contribute to RV dysfunction in patients with PAH. q RSNA, 2010 1 From the Department of Radiology (J.V., J.S., M.L.S.); Department of Medicine, Division of Pulmonary and Critical Care Medicine (S.S., D.M.B., N.L., R.E.G., S.C.M., P.M.H.); and Division of Cardiology (J.A.C.L.), Johns Hopkins University School of Medicine, Nelson Basement MRI 143, 600 N Wolfe St, Baltimore, MD 21287; Department of Radi- ology and Imaging Sciences, National Institutes of Health, Bethesda, Md (C.T.S., D.A.B.); Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (T.A.G., J.Z.,); and Eberhard Karls University, Tübingen Germany (J.V.). Received April 8, 2010; revision requested May 26; revision received June 29; accepted July 14; final version accepted August 16. P.M.H. supported by National Institutes of Health. Address correspondence to J.V. (e-mail: jclauss1@jhmi.edu). q RSNA, 2010