Time course of recovery of left atrial function following revversible ichemia in dogs assessed by digital substraction angiography

We assessed the postischemic recovery of left atrial (LA) and left ventricular (LV) performance by densitometric anlysis of digital substruction angiography in 10 anesthetized dogs. Each dog underwent 60-min left circumflex soronary artery occlusion, followed by 120-min reperfusion. Time-density (T-D) curves were obtained by densitometry in LA, global LV, LV normal anterior and ischmic posterior segment. From the LA T-D curve, passive atrial emptying count(P), active atrial emptying count(A), and total atrial emptying(T) were derived . Left ventricular ejection fraction (LVEF), peak ejection rate (PER), and peak filling rate (PFR) were derived from LV T-D curve and its frist derivative curve. A/T, as an index of atrial contraction, significantly increased, and P/T significantly decreased during occlusion (from 1 to 1.44±0.24