Background: One of the diagnostic criteria of low cardiac output syndrome (LOS) is a cardiac index of less than 1.8 l/min/m2. However, recognition of this syndrome differs among intensivists as to whether or not LOS is synonymous with cardiogenic shock.
Case reports: Here, we present two cases of heart failure who were initially treated with diuretics and subsequently fell into a state of low cardiac output. We treated the patient with low blood pressure with inotropes and the patient with high blood pressure with a vasodilator according to their hemodynamics. We observed that cardiac power was the most significant hemodynamic change in response to these treatments. In this paper, we discuss the definition of LOS and show several criteria for determining LOS.
Conclusions: Broadly, there are several conditions of determining LOS. Even with those conditions, we should still be aware of the pathophysiology of each patient with heart failure. We propose that the definition of LOS should be a state of low cardiac output with corresponding symptoms, even if their blood pressure is high.