Cardiovascular magnetic resonance evaluation of effusive and constrictive physiologies

This thesis presents an exploration of cardiovascular magnetic resonance (CMR) in the evaluation of effusive and constrictive heart conditions. Central to the thesis is advanced CMR as a diagnostic tool in pericardial effusion and constrictive pericarditis.

Studies I and II concern the application of T1 mapping for the characterization of pleural and pericardial effusions and attempts to enhance the understanding of the dynamics of extracellular gadolinium-based contrast agents (GBCA) in effusion fluid. Study II establishes normal T1 values at 1.5 T in the pericardial fluid of healthy individuals, providing a benchmark for future studies. Studies III and IV concern ventricular interdependence, a crucial aspect in evaluating constrictive physiology. Ventricular interdependence is measured by quantifying the respiratory variation in peak early transvalvular blood flow velocities. In Study III, an open-source software tool to perform semi-automated image analysis of real-time phase contrast (RT-PC) images is developed, and normal values are established. In Study IV, the repeatability and reproducibility of the method are tested.

This thesis concludes that CMR can become a valuable tool in evaluating pericardial effusion and constrictive pericarditis. Both molecular imaging evaluation of effusive fluids and hemodynamic assessment of ventricular interdependence are feasible using CMR.

List of scientific papers

I. Thalén S, Maanja M, Sigfridsson A, Maret E, Sörensson P, Ugander M. The dynamics of extracellular gadolinium-based contrast agent excretion into pleural and pericardial effusions quantified by T1 mapping cardiovascular magnetic resonance. J Cardiovasc Magn Reson. 2019;21(1):71.
https://doi.org/10.1186/s12968-019-0580-1

II. Thalén S, Ramos JG, Engblom H, Sigfridsson A, Sörensson P, Ugander M. Normal values for native T1 at 1.5 T in the pericardial fluid of healthy volunteers. European Heart Journal - Imaging Methods and Practice. 2023;1(2):qyad028.
https://doi.org/10.1093/ehjimp/qyad028

III. Thalén S, Heiberg E, Sörensson P , Giese D, Sigfridsson A, Ugander M. Normal values for mitral and tricuspid early inflow blood flow velocity variation using real time phase contrast cardiovascular magnetic resonance. [Submitted]

IV. Thalén S, Wieslander B, Sigfridsson S, Giese D, Sörensson P, Ugander M. Test-retest repeatability and inter-observer reproducibility of ventricular interdependence measured using semi-automatic analysis of real time phase contrast cardiovascular imaging. [Manuscript]