Award article: Microcirculatory Society Award for Excellence in Lymphatic Research: time course of myocardial interstitial edema resolution and associated left ventricular dysfunction.

OBJECTIVE: Although the causal relationship between acute myocardial edema and cardiac dysfunction has been established, resolution of myocardial edema and subsequent recovery of cardiac function have not been established. The time to resolve myocardial edema and the degree that cardiac function is depressed after edema resolves are not known. We therefore characterized temporal changes in cardiac function as acute myocardial edema formed and resolved.
METHODS: Acute myocardial edema was induced in the canine model by elevating coronary sinus pressure for three hours. Myocardial water content and cardiac function were determined before and during coronary sinus pressure elevation, and after coronary sinus pressure restoration.
RESULTS: Although no change in systolic properties was detected, accumulation of water in myocardial interstitium was associated with increased diastolic stiffness. When coronary sinus pressure was relieved, myocardial edema resolved within 180 minutes. Diastolic stiffness, however, remained significantly elevated compared with baseline values, and cardiac function remained compromised.
CONCLUSIONS: The present work suggests that the cardiac dysfunction caused by the formation of myocardial edema may persist after myocardial edema resolves. With the advent of new imaging techniques to quantify myocardial edema, this insight provides a new avenue for research to detect and treat a significant cause of cardiac dysfunction.