Dynamic perfusion MRI: Capability for evaluation of disease severity and progression of pulmonary arterial hypertension in patients with connective tissue disease

Purpose: To prospectively evaluate the capability of dynamic perfusion MRI for assessment of disease severity and progression to pulmonary arterial hypertension (PAH) in connective tissue disease (CTD) patients. Materials and Methods: In all, 18 gender- and age-matched CTD patients without and with PAH and nine healthy volunteers underwent dynamic perfusion MRI, Doppler echocardiography, and pulmonary function test. Disease severity of CTD was assessed in terms of diffusing capacity for carbon monoxide (%DL_CO) and estimated systolic pulmonary arterial pressure (sPAP), and progression of PAH in terms of pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR). From calculated pulmonary perfusion parameter maps, means of pulmonary blood flow (mPBF), pulmonary blood volume (mPBV), and mean transit time (mMTT) were determined as averages of all region of interest (ROI) measurements. To determine disease severity in CTD, all parameters were statistically correlated with sPAP and %DL_CO. To determine progression to PAH, all parameters were statistically correlated with mPAP and PVR. Results: All pulmonary perfusion parameters correlated significantly with sPAP and %DL_CO (P < 0.05). mPBF and mPBV correlated significantly with mPAP and moderately with PVR (P < 0.05). Conclusion: Dynamic perfusion MRI can be used for assessment of disease severity and progression of PAH in CTD patients.