Journal of Cardiovascular Magnetic Resonance (Mar 2021)

Right ventricular myocardial deoxygenation in patients with pulmonary artery hypertension

  • Karthigesh Sree Raman,
  • Ranjit Shah,
  • Michael Stokes,
  • Angela Walls,
  • Richard J. Woodman,
  • Rebecca Perry,
  • Jennifer G. Walker,
  • Susanna Proudman,
  • Carmine G. De Pasquale,
  • David S. Celermajer,
  • Joseph B. Selvanayagam

DOI
https://doi.org/10.1186/s12968-020-00694-0
Journal volume & issue
Vol. 23, no. 1
pp. 1 – 11

Abstract

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Abstract Background In pulmonary arterial hypertension (PAH), progressive right ventricular (RV) dysfunction is believed to be largely secondary to RV ischaemia. A recent pilot study has demonstrated the feasibility of Oxygen-sensitive (OS) cardiovascular magnetic resonance (CMR) to detect in-vivo RV myocardial oxygenation. The aims of the present study therefore, were to assess the prevalence of RV myocardial ischaemia and relationship with RV myocardial interstitial changes in PAH patients with non-obstructive coronaries, and corelate with functional and haemodynamic parameters. Methods We prospectively recruited 42 patients with right heart catheter (RHC) proven PAH and 11 healthy age matched controls. The CMR examination involved standard functional imaging, OS-CMR imaging and native T1 mapping. An ΔOS-CMR signal intensity (SI) index (stress/rest signal intensity) was acquired at RV anterior, RV free-wall and RV inferior segments. T1 maps were acquired using Shortened Modified Look-Locker Inversion recovery (ShMOLLI) at the inferior RV segment. Results The inferior RV ΔOS-CMR SI index was significantly lower in PAH patients compared with healthy controls (9.5 (– 7.4–42.8) vs 12.5 (9–24.6)%, p = 0.02). The inferior RV ΔOS-CMR SI had a significant correlation to RV inferior wall thickness (r = – 0.7, p < 0.001) and RHC mean pulmonary artery pressure (mPAP) (r = – 0.4, p = 0.02). Compared to healthy controls, patients with PAH had higher native T1 in the inferior RV wall: 1303 (1107–1612) vs 1232 (1159–1288)ms, p = 0.049. In addition, there was a significant difference in the inferior RV T1 values between the idiopathic PAH and systemic sclerosis associated PAH patients: 1242 (1107–1612) vs 1386 (1219–1552)ms, p = 0.007. Conclusion Blunted OS-CMR SI suggests the presence of in-vivo microvascular RV dysfunction in PAH patients. The native T1 in the inferior RV segments is significantly increased in the PAH patients, particularly among the systemic sclerosis associated PAH group.

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