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Elevated blood lactate levels are strongly associated with mortality in patients with cardiogenic shock. Recent evidence suggests that the degree and rate at which blood lactate levels decrease after the initiation of treatment may be equally important in patient prognosis. We performed a systematic review and meta-analysis to evaluate the usefulness of lactate clearance as a prognostic factor in cardiogenic shock.We performed searches of Ovid MEDLINE, Elsevier EMBASE, EBM Reviews-Cochrane Central Register of Controlled Trials, and Web of Science to identify studies comparing lactate clearance between survivors and nonsurvivors at one or more timepoints. Both prospective and retrospective studies were eligible for inclusion. Two study investigators independently screened, extracted data, and assessed the quality of all included studies. Twelve studies were included in the meta-analysis. The median lactate clearance at 6-8 hours was 21.9% (interquartile range [IQR] 14.6%-42.1%) in survivors and 0.6% (IQR -3.7% to 14.6%) in nonsurvivors. At 24 hours, the median lactate clearance was 60.7% (IQR 58.1%-76.3%) and 40.3% (IQR 30.2%-55.8%) in survivors and nonsurvivors, respectively. Accordingly, the pooled mean difference in lactate clearance between survivors and nonsurvivors at 6-8 hours was 17.3% (95% CI 11.6%-23.1%, P.001) at 6-8 hours and 27.9% (95% CI 14.1%-41.7%, P.001) at 24 hours.Survivors had significantly greater lactate clearance at 6-8 hours and at 24 hours compared with nonsurvivors, suggesting that lactate clearance is an important prognostic marker in cardiogenic shock.

Despite increasing prevalence in critical care units, cardiogenic shock related to HF (HF-CS) is incompletely understood and distinct from acute myocardial infarction related CS. This review highlights the pathophysiology, evaluation, and contemporary management of HF-CS.

Background Understanding the prognostic impact of right ventricular dysfunction (RVD) in cardiogenic shock (CS) is a key step toward rational diagnostic and treatment algorithms and improved outcomes. Using a large multicenter registry, we assessed (1) the association between hemodynamic markers of RVD and in-hospital mortality, (2) the predictive value of invasive hemodynamic assessment incorporating RV evaluation, and (3) the impact of RVD severity on survival in CS. Methods and Results Inpatients with CS owing to acute myocardial infarction (AMI) or heart failure (HF) between 2016 and 2019 were included. RV parameters (right atrial pressure, right atrial/pulmonary capillary wedge pressure [RA/PCWP], pulmonary artery pulsatility index [PAPI], and right ventricular stroke work index [RVSWI]) were assessed between survivors and nonsurvivors, and between etiology and SCAI stage subcohorts. Multivariable logistic regression analysis determined hemodynamic predictors of in-hospital mortality; the resulting models were compared with SCAI staging alone. Nonsurvivors had a significantly higher right atrial pressure and RA/PCWP and lower PAPI and RVSWI than survivors, consistent with more severe RVD. Compared with AMI, patients with HF had a significantly lower RA/PCWP (0.58 vs 0.66, P = .001) and a higher PAPI (2.71 vs 1.78, P Conclusions RVD is associated with poor outcomes in CS, with key differences across etiology and shock severity. Further studies are needed to assess the usefulness of RVD assessment in guiding therapy.

Purpose Sympathetic activation results in a functional distribution of venous blood from the unstressed reservoir to the hemodynamically active stressed compartment. Such redistribution has been hypothesized to contribute importantly to the elevated filling pressures observed in decompensated heart failure and cardiogenic shock (CS). We recently reported a novel computational method to estimate SBV by fitting measured hemodynamic data from patients to outputs from a cardiovascular model. We hypothesized that estimated stressed blood volume (eSBV) may correlate with severity and clinical outcomes in cardiogenic shock. Methods Hemodynamic parameters including eSBV were compared among a subset of patients from the Cardiogenic Shock Working Group (CSWG) registry who had a complete set of hemodynamic data. eSBV was compared across shock etiologies (AMI vs HF-CS), SCAI stage, and between survivors and non-survivors. Results Among 528 CSWG registry patients analyzed, 25.4% had AMI-CS and 61.9% had HF-CS. Mean eSBV was 2423 ± 531 mL/70 kg (normal value ∼1500 mL) and was similar between the AMI-CS and HF-CS subgroups (2421 ± 478 vs 2342 ± 599 mL/70kg, p=0.90). eSBV increased with increasing SCAI stage (B, 2029 ± 540; C, 2305 ± 505; D, 2496 ± 507; E, 2707 ± 420 mL/70 kg, p Conclusion eSBV is a novel integrated index of congestion which correlates with shock severity. eSBV was higher in patients with HF-CS who died while no difference was observed in AMI-CS, suggesting that congestion may play a more significant role in the deterioration of patients with HF-CS.

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 the IABP in acute coronary syndrome (ACS)-related CS. Acute-on-chronic heart failure has become an increasingly recognized, distinct cause of CS (HF-CS). The pathophysiology of HF-CS differs from that of ACS-CS because 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 patients with HF-CS 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 in the treatment of HF-CS. It also briefly discusses new strategies for vascular access as well as fully implantable versions for longer duration of support.

Cardiogenic shock (CS) is a condition associated with high mortality rates in which prognostication is uncertain for a variety of reasons, including its myriad causes, its rapidly evolving clinical course and the plethora of established and emerging therapies for the condition. A number of validated risk scores are available for CS prognostication; however, many of these are tedious to use, are designed for application in a variety of populations and fail to incorporate contemporary hemodynamic parameters and contemporary mechanical circulatory support interventions that can affect outcomes. It is important to separate patients with CS who may recover with conservative pharmacological therapies from those in who may require advanced therapies to survive; it is equally important to identify quickly those who will succumb despite any therapy. An ideal risk-prediction model would balance incorporation of key hemodynamic parameters while still allowing dynamic use in multiple scenarios, from aiding with early decision making to device weaning. Herein, we discuss currently available CS risk scores, perform a detailed analysis of the variables in each of these scores that are most predictive of CS outcomes and explore a framework for the development of novel risk scores that consider emerging therapies and paradigms for this challenging clinical entity.

Despite increasing prevalence in critical care units, cardiogenic shock related to HF (HF-CS) is incompletely understood and distinct from acute myocardial infarction related CS. This review highlights the pathophysiology, evaluation, and contemporary management of HF-CS.