Diagnosis and Definition of Cardiogenic Shock

Cardiogenic shock is one of four types of shock described by Weil and Shubin. Conceptually, cardiogenic shock is a state of circulatory failure that results in inadequate cellular oxygen utilization, due to an underlying cardiac or cardiopulmonary abnormality. A pathophysiological definition consists of three components: an underlying cardiopulmonary pathology commensurate with the state of shock and evidence of circulatory failure and hypoperfusion. The clinical definition should reflect this pathophysiological definition of cardiogenic shock; but clinical trials, consensus documents and clinical guidelines have adopted variable clinical definitions and criteria. Indeed, some of the definitions/diagnostic criteria fail to distinguish cardiogenic shock from advanced heart failure. There is also a growing nomenclature to describe the clinical presentation of cardiogenic shock. In this chapter, the pathophysiology, nomenclature and clinical definition of cardiogenic shock and refractory shock are discussed.