In pulmonary arterial hypertension (PAH), cardiovascular magnetic resonance (CMR) has been proposed as a standard for the assessment of right ventricular function and characteristics of the pulmonary vascular bed [1, 2]. Accurate assessment of stroke volume (SV) by CMR is critical in this respect, since earlier studies revealed that SV is closely related to prognosis and that a change in SV reflects treatment effects [3].SV can be assessed by measuring flow in the main pulmonary artery (PA) using phase-contrast CMR (PC CMR) protocols [6] (Fig....

14 PAH (f/m-9/5, mean age 47,6 years ±12) underwent both CMR and right-sided heart catheterization. CMR was performed at1.5T system(AVANTO, Siemens) using velocity-encoded MRsequences (PC CMR) and SSFP-cine. PCCMR was acquired during continuous breathing with velocity encoding perpendicular to the imaging plane and a velocity sensitivity of 120 cm/sec ( Fig. 2, Fig. 3 ). Slice orientation wasorthogonal to the main PA, slice thickness - 6 mm. Aortic flow measurement was performed for calculation the ratio between pulmonary and systemic flow, imaging plane was 2–4...

Regression analysis has been done,p < 0.0001. For SV by PA flow versus Fick, r = 0.41. For SV by LV volumes versus Fick, r =0.45. For SV by RV volumes versus Fick, r =0.38. For SV by aorta flow versus Fick yielded r =0.37. For SV by PA flowversusSV by RV volumes r=0,7. Pulmonary to systemic flow ratio (Qp:Qs) more than 1,1 measured by volumetric analysis (RVSV-LVSV) were found in 2 patients with significant (grade III-IV) tricuspid regurgitation (Fig. 6). Qp:Qs>1,1 measured by VENC...

In conclusion, CMR-derived SV has poor accuracy in PAH patients with a tendency to overestimate SVvalue. Volumetric analysis is more accurate for measurement SV in patients with pulmonary hypertension. Despite of poor agreement with invasive data SV calculated using volumetric analysis could be used for follow-up of PAH patients.

Torbicki A:Cardiac magnetic resonance in pulmonary arterial hypertension: a step in the right direction. EHJ2007,28(10):1187-9. cLure LE, Peacock AJ:Imaging of the heart in pulmonary hypertension.Int J Clin Pract Suppl2007,(156):15-26. van Wolferen SA, Marcus JT, Boonstra A, Marques KM, Bronzwaer JG, Spreeuwenberg MD,et al.:Prognostic value of right ventricular mass, volume, and function in idiopathic pulmonary arterial hypertension.EHJ2007,28(10):1250-7. Firmin DN, Nayler GL, Klipstein RH, Underwood SR, Rees RS, Longmore DB:In vivo validation of MR velocity imaging J Comput Assist Tomogr1987,11(5):751-6 Bogren HG, Buonocore MH:Complex flow patterns in...