Abstract 4733: Impact of Pericardial Adhesions on Diastolic Transmitral Flow Efficiency: Analysis by Vortex Formation Time
Pericardial adhesions impair diastolic filling. Early diastolic flow forms a vortex ring, which makes fluid transport more efficient (compared to a jet alone). The vortex is characterized by a Vortex Formation Time (VFT) with an optimal value range from 3.3 to 4.5. We hypothesized that diastolic filling efficiency is suboptimal in a left ventricle (LV) with pericardial adhesions. In 8 open-chest adult pigs, the heart was exposed and pericardial adhesion simulated by tissue glue instilled into the pericardial space. We studied transmitral flow and assessed VFT at baseline and during the simulated pericardial adhesions. See Table⇓. Changes in mean aortic pressure (MAP) and heart rate (HR) were not significant. However, cardiac output (CO) and the magnitude of peak negative dP/dt (−dP/dt) decreased significantly. Although changes in E/A ratio and LV end-diastolic pressure (LVEDP) were not statistically significant, ejection fraction (EF), left ventricular end-diastolic volume (LVEDV) decreased significantly, and the time constant of LV pressure decay (Tau) increased significantly. These hemodynamic changes were associated with a significant decrease in VFT. The experimental study shows that pericardial adhesions can negatively impact the efficiency of transmitral flow, as documented by the decrease of the mean VFT value from the optimal value range.