The Stages of CS: Clinical and Translational Update

With improvements in cardiovascular care, and routine percutaneous coronary intervention for ST elevation myocardial infarction, more patients are surviving following acute coronary syndromes. However, a minority of patients develop cardiogenic shock which results in approximately 50% 30-day mortality. There are various ways to classify cardiogenic shock, and much has been written about this topic in recent years. This review will examine recent developments and put them in context.

The large randomized trials of cardiogenic shock treatments such as the IABP-SHOCK II trial used a clinical definition of shock including hypotension (systolic blood pressure of 90 mmHg or less, or requirement of vasopressors to maintain such a blood pressure), as well as hypoperfusion. However, while this defines a minimum standard to define cardiogenic shock, it does not distinguish between a patient on a single vasoconstrictor and one who is on multiple high dose infusions or one on extracorporeal membrane oxygenation. The Society for Cardiac Angiography and Intervention recently published an expert consensus statement defining stages of cardiogenic shock, from at risk to beginning, classic, deteriorating, and extremis cardiogenic shock stages. The simple framework has been validated rapidly in multiple populations including the intensive care unit, a post-myocardial infarction population, an out of hospital cardiac arrest population, and most recently in a multicenter shock collaborative, Classification is fundamental to understanding a disease state, and crafting solutions to improve outcomes. The last 20 years has witnessed an explosion of percutaneous mechanical circulatory support devices of increasing sophistication and capability, and yet there has been little progress in improving outcomes of cardiogenic shock. Hopefully, the next 20 years will see massive advances in understanding of the complexities of the various stages of cardiogenic shock. With such knowledge, it is likely that targeted treatments will be developed and the mortality of this disease will finally plummet.