Cardiac contractility was studied in a clinically relevant conscious swine model simulating human hemodynamics during endotoxemia. The slope of the end-systolic pressure-volume relationship [end-systolic elastance (E_ES)] was used as a load-independent contractility index. Chronic instrumentation in 10 pigs included two pairs of endocardial ultrasonic crystals for measuring internal major and minor axial dimensions of the left ventricle, a micromanometer for left ventricular pressure measurement, and a thermodilution pulmonary artery catheter. After a 10-day recovery period, control measurements of cardiac hemodynamic function were obtained. The following week, Escherichia coli endotoxin (10 µg · kg¹ · h¹) was administered intravenously for 24 h. E_ES increased 1 h after endotoxin infusion and decreased beyond 7 h. The later hemodynamic changes resembled human cardiovascular performance during endotoxemia more closely than the changes during the acute phase. E_ES decreased in the later phase. A similar biphasic response of E_ES has been reported during a tumor necrosis factor- (TNF) challenge. Even though plasma TNF was highest at 1 h and declined thereafter in this study, no consistent relationship between TNF and E_ES was identified, and TNF levels did not correlate directly with the changes in E_ES.

contractility; tumor necrosis factor-; endotoxin; hemodynamics; left ventricle

This article has been cited by other articles:

				D. Konrad, M. Haney, G. Johansson, M. Wanecek, E. Weitzberg, and A. Oldner Cardiac effects of endothelin receptor antagonism in endotoxemic pigs Am J Physiol Heart Circ Physiol, August 1, 2007; 293(2): H988 - H996. [Abstract] [Full Text] [PDF]

				C. D. Raeburn, C. M. Calkins, M. A. Zimmerman, Y. Song, L. Ao, A. Banerjee, A. H. Harken, and X. Meng ICAM-1 and VCAM-1 mediate endotoxemic myocardial dysfunction independent of neutrophil accumulation Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2002; 283(2): R477 - R486. [Abstract] [Full Text] [PDF]