Magnetic resonance imaging in thromboembolic pulmonary hypertension

Magnetic resonance imaging (MRI) in evaluation of the main, right and left artery (MPA, RPA, LPA) was performed in 12 patients with suspected chronic thromboembolic pulmonary hypertension (CTEPH) before pulmonary angiography. The central pulmonary vasculature was imaged using a 0.5 T Toshiba MRT50A with ''heart anatomy cardiac function analysis''. We performed ECG-gated spin-echo (SE) T1W, flip angle (FA) 90. TR 300-500 msec, TE-20 msec, gradient-echo (GE) Cine MR FA=30, TR=800 msec, TE=22 msec, ST=10 mm. All patients had right ventricular hypertrophy. We compared Cine MR with SE imaging for showing central pulmonary emboli in 11 patients. 4 patients from this group had the emboli in RPA, 2 patients in LPA and 5 patients in both. No false positive results were found. In 2 patients MRI repeated after thrombendarterectomy showed absence of previously visualized intraluminal thrombus, normal blood flow in MPA, RPA, LPA and the decline in right ventricular overload. In our study the ECG-gated MRI T1W and GE Cine allowed the visualization of central pulmonary thrombus. MRI seems to be a useful non-invasive technique for evaluation of the pulmonary vasculature in diagnosis of STEPH and after thrombendarterectomy. (author)