No abstract

BackgroundLeft atrial volume (LAV) and emptying fraction (LAEF) are phasic during cardiac cycle. Their relationships to left ventricular end diastolic pressure (LVEDP) have not been fully defined.MethodsForty one patients undergoing clinically indicated left heart catheterization were recruited for same day cardiovascular magnetic resonance (CMR). LAV and LAEF were assessed in cine images using biplane area and length method. Three phasic LAV was assessed at LV end systole (LAVmax), LV end diastole (LAVmin) and late LV diastole prior to LA contraction (LAVac). LAEF was assessed as global LAEF (LAEFTotal), passive (LAEFPassive) and active LAEF (LAEFContractile). The relationships of phasic LAV and LAEF to LVEDP were assessed using Receiver operating characteristic comparing areas under the curves (AUC).ResultsThe mean age of the patients was 59 years. A history of heart failure was present in 16 (39%) with NYHA functional class III or IV in 8 (20%) patients. Average LV ejection fraction was 49 ± 16% ranging from 10% to 74% and LVEDP by catheterization 14 ± 8 mmHg ranging from 4 mmHg to 32 mmHg. LAVmin had the strongest association with LVEDP elevation (>12 mmHg) (AUC 0.765, p = 0.002), as compared to LAVmax (AUC 0.677, p = 0.074) and LAVac (AUC 0.735, p = 0.008). Among three phasic LAEF assessed, LAEFTotal had the closest association with LVEDP elevation (AUC 0.780, p = 0.001), followed by LAEFContractile (AUC 0.698, p = 0.022) and LAEFPassive (AUC 0.656, p = 0.077).ConclusionsIncreased LAVmin and decreased LAEFTotal have the best performance in identifying elevated LVEDP among three phasic LAV and LAEF analyzed. Future studies should further characterize LA phasic indices in clinical outcomes.

Global and regional central TT can be assessed in the first pass perfusion imaging. Prolonged normalized global TT correlates with reduced EF in HFrEF and increased PCWP in HFpEF.

Lung perfusion imaging using a 2D saturation recovery SSFP perfusion MRI coupled with a model-independent deconvolution algorithm demonstrated physiologically consistent dynamic heterogeneity of lung perfusion distribution.

Background-Left atrial (LA) size and function reflect left ventricular (LV) hemodynamics. In the present study, we developed a novel method to determine LA circulation transit time (LATT) by MRI and demonstrated its close association with LV filling pressure. Methods and Results-All subjects were prospectively recruited and underwent contrast-enhanced MR dynamic imaging.Mean LATT was determined as the time for contrast to transit through the LA during the first pass. In an invasive study group undergoing clinically indicated cardiac catheterization (nϭ25), LATT normalized by R-R interval (nLATT) was closely associated with LV early diastolic pressure (rϭ0.