Contemporary approach to cardiogenic shock care: a state-of-the-art review

Cardiogenic shock (CS) is a time-sensitive and hemodynamically complex syndrome with a broad spectrum of etiologies and clinical presentations. Despite contemporary therapies, CS continues to maintain high morbidity and mortality ranging from 35 to 50%. More recently, burgeoning observational research in this field aimed at enhancing the early recognition and characterization of the shock state through standardized team-based protocols, comprehensive hemodynamic profiling, and tailored and selective utilization of temporary mechanical circulatory support devices has been associated with improved outcomes. In this narrative review, we discuss the pathophysiology of CS, novel phenotypes, evolving definitions and staging systems, currently available pharmacologic and device-based therapies, standardized, team-based management protocols, and regionalized systems-of-care aimed at improving shock outcomes. We also explore opportunities for fertile investigation through randomized and non-randomized studies to address the prevailing knowledge gaps that will be critical to improving long-term outcomes.

Sex-Related Differences in Patient Characteristics, Hemodynamics, and Outcomes of Cardiogenic Shock: INOVA-SHOCK Registry

Background

Little is known about sex-related differences in outcomes of patients with cardiogenic shock (CS) treated within a standardized team-based approach (STBA).

Methods

We evaluated 520 consecutive patients (151 women and 369 men) with CS due to acute myocardial infarction (AMI) and heart failure (HF) in a single-center registry (January 2017-December 2019) and examined outcomes according to sex and CS phenotype. The primary outcome was in-hospital mortality. Secondary outcomes included major adverse cardiac events, 30-day mortality, major bleeding, vascular complications, and stroke.

Results

Women with AMI-CS had higher baseline acuity (CardShock score: female [F]: 5.5 vs male [M]: 4.0; P = .04). Women with HF-CS more often presented with cardiac arrest (F: 12.4% vs M: 2.4%; P< .01) and had higher rates of vasopressor use (F: 70.8% vs M: 58.0%; P = .04) and mechanical circulatory support (F: 46.1% vs M: 32.5%; P = .04). There were no sex-related differences in in-hospital mortality for AMI-CS (F: 45.2% vs M: 36.9%; P = .28) and HF-CS (F: 28.1% vs M: 24.5%; P = .56). Women with HF-CS experienced higher rates of major bleeding (F: 25.8% vs M: 13.7%; P = .02) and vascular complications (F: 15.7% vs M: 6.1%; P = .01). However, female sex was not an independent predictor of these complications. No sex differences in survival were noted at 1 year.

Conclusions

Within an STBA, although women with AMI-CS and HF-CS presented with higher acuity, they experienced similar in-hospital mortality, major adverse cardiac events, 30-day mortality, stroke, and 30-day readmissions as men. Further research is needed to better understand the extent to which historical differences in CS outcomes can be mitigated by an STBA.

Early Recognition and Risk Stratification in Cardiogenic Shock: Well Begun Is Half Done

Cardiogenic shock is a complex syndrome manifesting with distinct phenotypes depending on the severity of the primary cardiac insult and the underlying status. As long as therapeutic interventions fail to divert its unopposed rapid evolution, poor outcomes will continue challenging health care systems. Thus, early recognition in the emergency setting is a priority, in order to avoid delays in appropriate management and to ensure immediate initial stabilization. Since advanced therapeutic strategies and specialized shock centers may provide beneficial support, it seems that directing patients towards the recently described shock network may improve survival rates. A multidisciplinary approach strategy commands the interconnections between the strategic role of the ED in affiliation with cardiac shock centers. This review outlines critical features of early recognition and initial therapeutic management, as well as the utility of diagnostic tools and risk stratification models regarding the facilitation of patient trajectories through the shock network. Further, it proposes the implementation of precise criteria for shock team activation and the establishment of definite exclusion criteria for streaming the right patient to the right place at the right time.

Systems of Care in Cardiogenic Shock

Outcomes for cardiogenic shock (CS) patients remain relatively poor despite significant advancements in primary percutaneous coronary interventions (PCI) and temporary circulatory support (TCS) technologies. Mortality from CS shows great disparities that seem to reflect large variations in access to care and physician practice patterns. Recent reports of different models to standardize care in CS have shown considerable potential at improving outcomes. The creation of regional, integrated, 3-tiered systems, would facilitate standardized interventions and equitable access to care. Multidisciplinary CS teams at Level I centers would direct care in a hub-and-spoke model through jointly developed protocols and real-time shared decision making. Levels II and III centers would provide early access to life-saving therapies and safe transfer to designated hub centers. In regions with large geographical distances, the implementation of telemedicine-cardiac intensive care unit (CICU) care can be an important resource for the creation of effective systems of care.

Management and Outcomes of Cardiogenic Shock in Cardiac ICUs With Versus Without Shock Teams

BACKGROUND

Single-center studies suggest that implementation of multidisciplinary cardiogenic shock (CS) teams is associated with improved CS survival.

OBJECTIVES

The aim was to characterize practice patterns and outcomes in the management of CS across multiple centers with versus without shock teams.

METHODS

The Critical Care Cardiology Trials Network is a multicenter network of cardiac intensive care units (CICUs) in North America. All consecutive medical admissions to each CICU (n = 24) were captured during annual 2-month collection periods (2017-2019; n = 6,872). Shock management and CICU mortality among centers with versus without shock teams were compared using inverse probability weighting.

RESULTS

Ten of the 24 centers had shock teams. Among 1,242 CS admissions, 44% were at shock team centers. The groups were well-balanced with respect to demographics, shock etiology, Sequential Organ Failure Assessment score, biochemical markers of end organ dysfunction, and invasive hemodynamics. Centers with shock teams used more pulmonary artery catheters (60% vs 49%; adjusted odds ratio [OR]: 1.86; 95% CI: 1.47-2.35; P < 0.001), less overall mechanical circulatory support (MCS) (35% vs 43%; adjusted OR: 0.74; 95% CI: 0.59-0.95; P = 0.016), and more advanced types of MCS (53% vs 43% of all MCS; adjusted OR: 1.73; 95% CI: 1.19-2.51; P = 0.005) rather than intra-aortic balloon pumps. The presence of a shock team was independently associated with lower CICU mortality (23% vs 29%; adjusted OR: 0.72; 95% CI: 0.55-0.94; P = 0.016).

CONCLUSIONS

In this multicenter observational study, centers with shock teams were more likely to obtain invasive hemodynamics, use advanced types of MCS, and have lower risk-adjusted mortality. A standardized multidisciplinary shock team approach may improve outcomes in CS.