Haemodynamic and metabolic consequences of elevated plasma free fatty acids during acute ischaemic left ventricular failure in dogs

Abstract

Haemodynamic and metabolic effects of elevated plasma concentrations of free fatty acids (FFA) were studied during acute ischaemic left ventricular failure in closed-chest anaesthetized dogs. Embolization of the left main coronary artery with 50 μm plastic microspheres induced severe depression of left ventricular performance as indicated by a marked increase in left ventricular end-diastolic pressure (LVEDP), and marked reductions in LV˙dP/dt_max, cardiac output and myocardial oxygen consumption (MVO₂). When stable conditions were reached, eight dogs received a triglyceride emulsion and heparin to raise plasma FFA. This was associated with increased MVO₂ and further elevation of LVEDP. In two dogs receiving the triglyceride emulsion but no heparin, plasma FFA was not elevated, and MVO₂ and LVEDP were unchanged. In conclusion, elevation of plasma FFA was associated with increased myocardial oxygen requirement and further depression of LV function in dogs with acute ischaemic LV failure.

Key Words:

• glucose
• lactate
• left ventricular function
• myocardial metabolism