Intra-aortic balloon pump for acute-on-chronic heart failure complicated by cardiogenic shock

The Intra-aortic balloon pump (IABP) is widely implanted as temporary mechanical circulatory support for cardiogenic shock (CS). However, its use is declining following the results of the IABP-SHOCK II trial, which failed to show a clinical benefit of IABP in acute coronary syndrome (ACS) related CS. Acute-on-chronic heart failure has become an increasingly recognized, distinct etiology of CS (HF-CS). The pathophysiology of HF-CS differs from ACS-CS, as it typically represents the progression from a state of congestion (with relatively preserved cardiac output) to a low output state with hypoperfusion. The IABP is a "volume displacement pump" that promotes forward flow from a high-capacitance reservoir to low-capacitance vessels, improving peripheral perfusion and decreasing left ventricular afterload in the setting of high filling pressures. The IABP can improve ventricular-vascular coupling and, therefore, myocardial energetics. Additionally, many HF-CS patients are candidates for cardiac replacement therapies (left ventricular assist device or heart transplantation), and, therefore, may benefit from a "bridge" strategy that stabilizes the hemodynamics and end-organ function in preparation for more durable therapies. Notably, the new United Network for Organ Sharing donor heart allocation system has recently prioritized patients on IABP support. This review describes the role of IABP for the treatment of HF-CS. It also briefly discusses new strategies for vascular access as well as a fully implantable versions for a longer duration of support.