Non-contrast Enhanced Cardiac Magnetic Resonance Imaging in the Diagnosis and Classification of Pulmonary Hypertension

Pulmonary hypertension (PH) is a life-threatening cardiovascular disease characterized by pathological elevation of mean pulmonary arterial pressure (mPAP) >/= 25 mmHg at rest. mPAP < 20 mmHg is defined as normal, values in the range between 21-24 mmHg are described as "borderline PH" diagnosed by right heart catheterization. Based on the etiology, PH is assigned to 5 groups (WHO, Data Point, 2008), whereas classification of disease is an important prognostic and therapy-deciding criterion.

Cardiac magnetic resonance tomography (CMR) provides a reliable technique to estimate elevated mean pulmonary arterial pressure from period of existence of a vortical motion of blood flow in the main pulmonary artery. Vortex can be visualized in 3-dimensional vector field, particle trace and streamline representations and can be analysed with respect to vortex related measures (geometry of center, vortex formation, vorticity, propagation dynamics …). Furthermore T1-mapping and non-contrast enhanced lung perfusion/ventilation scans represent promising techniques for PH characterization.

Aim of this explorative study is to 1. analyse PH-associated blood flow characteristics in the heart and the surrounding great vessels with respect to the 5 groups of PH, and 2. investigate the hemodynamic state of "borderline PH" compared to normal mPAP and manifest PH by non-contrast CMR.