Low cardiac output states and cardiogenic shock

Low cardiac output and cardiogenic shock are associated with high mortality. Among the multiple heterogeneous reasons for low cardiac output and cardiogenic shock acute coronary syndromes are the most frequent cause. Mortality is still approaching 50%. The extent of ischaemic myocardium has a profound impact on the initial, in-hospital, and post-discharge management and prognosis of the cardiogenic shock patient. Careful risk assessment for each patient, based on clinical criteria, is mandatory, to decide appropriately regarding revascularization by primary percutaneous coronary intervention or coronary artery bypass grafting, drug treatment by inotropes and vasopressors, mechanical circulatory support, additional intensive care treatment, triage among alternative hospital care levels, and allocation of clinical resources. This chapter will outline the underlying causes and diagnostic criteria, pathophysiology, and treatment of cardiogenic shock focussing on acute coronary syndromes, including mechanical complications and shock from right ventricular failure. There will be a major focus on potential therapeutic issues from an interventional cardiologist's and also an intensive care physician's perspective on the advancement of new therapeutical arsenals, both percutaneous mechanical circulatory support and pharmacological support. Since studying the cardiogenic shock population in randomized trials remains challenging, this chapter will also touch upon the specific challenges encountered in previous clinical trials and the implications for future perspectives in cardiogenic shock.