Implication of pulmonary-systemic flow information in the management of complex presentation of pulmonary arterial hypertension: exploring role of phase contrast MRI technique

Phase-contrast (PC) cardiovascular magnetic resonance (MR) is an established technique which can measure, non-invasively, all three directional components of the velocities of blood flow relative to all four spatio-temporal dimensions of the heart and great vessels (1-4). The mapping of single component of “time-resolved velocity” directed perpendicularly through a 2D plane is extensively used for clinical measurements of flow volume (1-4). This technique provides measurements of forward, regurgitant and shunt flows in cardiovascular disease (5). Application of the same technology enables evaluation of flow across large aortic collaterals. Thus a measure of shunting between systemic to pulmonary (S-P) circulation or otherwise can be quantitatively obtained. Here we present a clinical example wherein information obtained from PC technique greatly assisted in the better understanding of patho-physiological basis of a uncommon clinical presentation.