Bedside hemodynamic monitoring provides useful information regarding the differential diagnosis of the various pathologic mechanisms of low output syndrome. It also allows recognition of hemodynamic subsets of patients with acute myocardial infarction. Furthermore, hemodynamic monitoring is necessary for prompt evaluation of the response to therapeutic interventions in patients with low output syndrome. In patients with acute myocardial infarction, hemodynamic indices can also be used for evaluation of immediate prognosis. Because bedside hemodynamic monitoring is relatively safe, and with proper precautionary measures the potential complications can be avoided, hemodynamic monitoring should be considered in the management of all critically ill cardiac patients.