Relationship of prolonged global and regional central circulatory transit time with hemodynamics

Methods Forty nine subjects undergoing clinically indicated right and left heart cardiac catheterization were prospectively recruited to undergo MRI in a 1.5T scanner. First pass perfusion using steady state free precession saturation recovery sequence was performed with gadolinium infusion at 0.01 mmol/kg. Global TT was defined as the time between the peaks of time intensity curves between the right atrium and the ascending aorta. Segmental TT included TT between right atrium to pulmonary artery (right heart TT), pulmonary artery to left atrium (pulmonary TT), or left atrium to ascending aorta (left heart TT). All TTs were normalized to heart rate. Multivariate regression analysis was performed to delineate the relationship of hemodynamic parameters measured during cardiac catheterization to TT. Receiver operating characteristic (ROC) analyses were performed to assess ability of global and segmental TT to predict elevated LVEDP.