Influence of cardiac arrest and SCAI shock stage on cardiac intensive care unit mortality

ICU management of cardiogenic shock before mechanical support

PURPOSE OF REVIEW

Treatment of cardiogenic shock remains largely driven by expert consensus due to limited evidence from randomized controlled trials. In this review, we aim to summarize the approach to the management of patients with cardiogenic shock in the ICU prior to mechanical circulatory support (MCS).

RECENT FINDINGS

Main topics covered in this article include diagnosis, monitoring, initial management and key aspects of pharmacological therapy in the ICU for patients with cardiogenic shock.

SUMMARY

Despite efforts to improve therapy, short-term mortality in patients with cardiogenic shock is still reaching 40-50%. Early recognition and treatment of cardiogenic shock are crucial, including early revascularization of the culprit lesion with possible staged revascularization in acute myocardial infarction (AMI)-CS. Optimal volume management and vasoactive drugs titrated to restore arterial pressure and perfusion are the cornerstone of cardiogenic shock therapy. The choice of vasoactive drugs depends on the underlying cause and phenotype of cardiogenic shock. Their use should be limited to the shortest duration and lowest possible dose. According to recent observational evidence, assessment of the complete hemodynamic profile with a pulmonary artery catheter (PAC) was associated with improved outcomes and should be considered early in patients not responding to initial therapy or with unclear shock. A multidisciplinary shock team should be involved early in order to identify potential candidates for temporary and/or durable MCS.

Implementation of a cardiogenic shock team in a tertiary academic center

OBJECTIVE

Observational studies have shown that the management of patients with cardiogenic shock (CS) by dedicated multidisciplinary teams improves clinical outcomes. Nevertheless, these studies reflect a specific organizational setting with most patients being transferred from referring hospitals, hospitalized in cardiac intensive care units (ICU), or treated with mechanical circulatory support (MCS) devices. The purpose of this study was to document the organization and outcomes of a CS team offering acute care in an all-comer population.

METHODS

A CS team was developed in a large academic tertiary institution. The team consisted of emergency care physicians, critical care cardiologists, interventional cardiologists, cardiac surgeons, ICU physicians, and heart failure specialists and was supported by a predefined operating protocol, a dedicated communication platform, and regular team meetings.

RESULTS

Over 12 months, 70 CS patients (69 ± 13 years old, 67% males) were included. Acute myocardial infarction (AMI-CS) was the most common cause (64%); 31% of the patients presented post-resuscitated cardiac arrest and 56% needed invasive mechanical ventilation (IMV). Coronary angiography was performed in 70% and 53% had percutaneous coronary intervention. MCS was used in 10% and 6% were referred for urgent cardiac surgery. The in-hospital mortality in our center was 40% with 39% of the patients dying within 24 h from presentation. Overall, 76% of the live patients were discharged home.

CONCLUSION

Across an all-comer population, AMI was the most common cause of CS. A significant number of patients presented post-cardiac arrest, and the majority required IMV. Mortality was high with a significant number dying within hours of presentation.

Cardiogenic shock as a health issue. Physiology, classification, and detection

Cardiogenic shock (CS) is a heterogeneous syndrome with high mortality and a growing incidence. It is characterized by an imbalance between the tissue oxygen demands and the capacity of the cardiovascular system to meet these demands, due to acute cardiac dysfunction. Historically, acute coronary syndromes have been the primary cause of CS. However, non-ischemic cases have seen a rise in incidence. The pathophysiology involves ischemic damage of the myocardium and a sympathetic, renin-angiotensin-aldosterone system and inflammatory response, perpetuating the situation of tissue hypoperfusion and ultimately leading to multiorgan dysfunction. The characterization of CS patients through a triaxial assessment and the widespread use of the Society for Cardiovascular Angiography and Interventions (SCAI) scale has allowed standardization of the severity stratification of CS; this, coupled with early detection and the "hub and spoke" approach, could contribute to improving the prognosis of these patients.

Shock Severity Classification and Mortality in Adults With Cardiac, Medical, Surgical, and Neurological Critical Illness

OBJECTIVE

To evaluate whether the Society for Cardiovascular Angiography and Interventions (SCAI) Shock Classification could perform risk stratification in a mixed cohort of intensive care unit (ICU) patients, similar to its validation in patients with acute cardiac disease.

METHODS

We included 21,461 adult Mayo Clinic ICU patient admissions from December 1, 2014, to February 28, 2018, including cardiac ICU (16.7%), medical ICU (37.4%), neurosciences ICU (27.7%), and surgical ICU (18.2%). The SCAI Shock Classification (a 5-stage classification from no shock [A] to refractory shock [E]) was assigned in each 4-hour period during the first 24 hours of ICU admission.

RESULTS

The median age was 65 years, and 43.2% were female. In-hospital mortality occurred in 1611 (7.5%) patients, with a stepwise increase in in-hospital mortality in each higher maximum SCAI Shock stage overall: A, 4.0%; B, 4.6%; C, 7.0%; D, 13.9%; and E, 40.2%. The SCAI Shock Classification provided incremental mortality risk stratification in each ICU, with the best performance in the cardiac ICU and the worse performance in the neurosciences ICU. The SCAI Shock Classification was associated with higher adjusted in-hospital mortality (adjusted odds ratio, 1.32 per each stage; 95% CI, 1.24 to 1.41; P<.001); this association was not observed in the neurosciences ICU when considered separately.

CONCLUSION

The SCAI Shock Classification provided incremental mortality risk stratification beyond established prognostic markers across the spectrum of medical and surgical critical illness, proving utility outside its original intent.

Association of systemic inflammation with shock severity, 30-day mortality, and therapy response in patients with cardiogenic shock

BACKGROUND

Mortality in cardiogenic shock (CS) remains high even when mechanical circulatory support (MCS) restores adequate circulation. To detect a potential contribution of systemic inflammation to shock severity, this study determined associations between C-reactive protein (CRP) concentrations and outcomes in patients with CS.

METHODS

Unselected, consecutive patients with CS and CRP measurements treated at a single large cardiovascular center between 2009 and 2019 were analyzed. Adjusted regression models were fitted to evaluate the association of CRP with shock severity, 30-day in-hospital mortality and treatment response to MCS.

RESULTS

The analysis included 1116 patients [median age: 70 (IQR 58-79) years, 795 (71.3%) male, lactate 4.6 (IQR 2.2-9.5) mmol/l, CRP 17 (IQR 5-71) mg/l]. The cause of CS was acute myocardial infarction in 530 (48%) patients, 648 (58%) patients presented with cardiac arrest. Plasma CRP concentrations were equally distributed across shock severities (SCAI stage B-E). Higher CRP concentrations were associated with 30-day in-hospital mortality (8% relative risk increase per 50 mg/l increase in CRP, range 3-13%; p < 0.001), even after adjustment for CS severity and other potential confounders. Higher CRP concentrations were only associated with higher mortality in patients not treated with MCS [hazard ratio (HR) for CRP > median 1.50; 95%-CI 1.21-1.86; p < 0.001], but not in those treated with MCS (HR for CRP > median 0.92; 95%-CI 0.67-1.26; p = 0.59; p-interaction = 0.01).

CONCLUSION

Elevated CRP concentrations are associated with increased 30-day in-hospital mortality in unselected patients with cardiogenic shock. The use of mechanical circulatory support attenuates this association.

Heart failure related cardiogenic shock: An ISHLT consensus conference content summary

In recent years, there have been significant advancements in the understanding, risk-stratification, and treatment of cardiogenic shock (CS). Despite improved pharmacologic and device-based therapies for CS, short-term mortality remains as high as 50%. Most recent efforts in research have focused on CS related to acute myocardial infarction, even though heart failure related CS (HF-CS) accounts for >50% of CS cases. There is a paucity of high-quality evidence to support standardized clinical practices in approach to HF-CS. In addition, there is an unmet need to identify disease-specific diagnostic and risk-stratification strategies upon admission, which might ultimately guide the choice of therapies, and thereby improve outcomes and optimize resource allocation. The heterogeneity in defining CS, patient phenotypes, treatment goals and therapies has resulted in difficulty comparing published reports and standardized treatment algorithms. An International Society for Heart and Lung Transplantation (ISHLT) consensus conference was organized to better define, diagnose, and manage HF-CS. There were 54 participants (advanced heart failure and interventional cardiologists, cardiothoracic surgeons, critical care cardiologists, intensivists, pharmacists, and allied health professionals), with vast clinical and published experience in CS, representing 42 centers worldwide. State-of-the-art HF-CS presentations occurred with subsequent breakout sessions planned in an attempt to reach consensus on various issues, including but not limited to models of CS care delivery, patient presentations in HF-CS, and strategies in HF-CS management. This consensus report summarizes the contemporary literature review on HF-CS presented in the first half of the conference (part 1), while the accompanying document (part 2) covers the breakout sessions where the previously agreed upon clinical issues were discussed with an aim to get to a consensus.

DIFFERENCES IN MANAGEMENT AND PROGNOSTICATION OF CARDIOGENIC SHOCK PATIENTS IN THE PRESENCE AND ABSENCE OF OUT-OF-HOSPITAL CARDIAC ARREST

ABSTRACT

Background: The clinical spectrum of acute myocardial infarction complicated by cardiogenic shock (AMICS) varies. Out-of-hospital cardiac arrest (OHCA) can be the first sign of cardiac failure, whereas others present with various degrees of hemodynamic instability (non-OHCA). The aim of the present study was to explore differences in prehospital management and characteristics of survivors and nonsurvivors in AMICS patients with OHCA or non-OHCA. Methods: Data analysis was based on patient data from the RETROSHOCK cohort comprising consecutive AMICS patients admitted to two tertiary cardiac centers between 2010 and 2017. Results: 1,716 AMICS patients were included and 42% presented with OHCA. Mortality in OHCA patients was 47% versus 57% in the non-OHCA group. Almost all OHCA patients were intubated before admission (96%). In the non-OHCA group, prehospital intubation (25%) was associated with a better survival ( P < 0.001). Lactate level on admission demonstrated a linear relationship with mortality in OHCA patients. In non-OHCA, probability of death was higher for any given lactate level <12 mmol/L compared with OHCA. However, a lactate level >7 mmol/L in non-OHCA did not increase mortality odds any further. Conclusion: Mortality was almost doubled for any admission lactate level up to 7 mmol/L in non-OHCA patients. Above this level, mortality remained unchanged in non-OHCA patients but continued to increase in OHCA patients. Prehospital intubation was performed in almost all OHCA patients but only in one of four patients without OHCA. Early intubation in non-OHCA patients was associated with a better outcome.

Acute Triple Coronary Artery Occlusion Leading to Cardiogenic Shock and Cardiac Arrest Emphasizing the Role of Mechanical Circulatory Support (Escalate before It's Too Late)

We report a case of cardiac arrest in a 38-year-old male with no past medical history who presented as a case of ST-segment elevation myocardial infarction, and coronary angiography showed triple coronary artery thrombosis complicated with cardiogenic shock (CS) that warrants starting on inotropic support and insertion of intra-aortic balloon pump. CS diagnosis with a high likelihood of deterioration was established based on hemodynamics assessment; hence, an early prompt decision for escalation of mechanical circulatory support to Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) was made, which helped to prevent the patient's further deterioration and organ damage. The patient had uneventful VA-ECMO decannulation and was transferred to the ward and discharged after 28 days in stable condition on oral medical therapy and was following up regularly in the cardiology clinic. Therefore, early hemodynamics assessment in acute myocardial infarction CS cases will help predict rapid worsening, which may require prompt escalation of mechanical circulatory support and perhaps improve the outcome.

Impact of a Cardiogenic Shock Program on Mortality in a Non-Transplant Hospital

INTRODUCTION

Cardiogenic shock is associated with high in-hospital morbidity and mortality. Improvements in this care process could lead to better outcomes.

METHODS

This retrospective study of patients with cardiogenic shock compared two periods: no specific program to address cardiogenic shock and implementation of a cardiogenic shock program. This program included the establishment of a multidisciplinary team (shock team), early alert to the transplant hospital, initiation of a ventricular assist extracorporeal membrane oxygenation (ECMO) program, and extension of continuous care by acute cardiovascular care specialists. The primary objective was to analyse whether there were differences between in-hospital mortality and mortality during follow-up. Predictors of in-hospital mortality were examined as a secondary objective.

RESULTS

A total of 139 patients were enrolled: 69 of them in the previous period and 70 in the cardiogenic shock program period. There was a significant reduction in in-hospital mortality (55.1% vs 37.1%; p=0.03) and mortality during follow-up (62.7% vs 44.6%; p=0.03) in the second period. Diabetes mellitus, ejection fraction, out-of-hospital cardiac arrest, and implementation of the cardiogenic shock program were independent predictors of in-hospital mortality.

CONCLUSIONS

The implementation of a comprehensive cardiogenic shock program in a non-transplanting hospital improved in-hospital and follow-up mortality of patients in cardiogenic shock.

Systematic Assessment of Shock Severity in Postoperative Cardiac Surgery Patients

BACKGROUND

The Society for Cardiovascular Angiography and Interventions (SCAI) shock classification has been shown to provide robust mortality risk stratification in a variety of cardiovascular patients.

OBJECTIVES

This study sought to evaluate the SCAI shock classification in postoperative cardiac surgery intensive care unit (CSICU) patients.

METHODS

This study retrospectively analyzed 26,792 postoperative CSICU admissions at a heart center between 2012 and 2022. Patients were classified into SCAI shock stages A to E using electronic health record data. Moreover, the impact of late deterioration (LD) as an additional risk modifier was investigated.

RESULTS

The proportions of patients in SCAI shock stages A to E were 24.4%, 18.8%, 8.4%, 35.5%, and 12.9%, and crude hospital mortality rates were 0.4%, 0.6%, 3.3%, 4.9%, and 30.2%, respectively. Similarly, the prevalence of postoperative complications and organ dysfunction increased across SCAI shock stages. After multivariable adjustment, each higher SCAI shock stage was associated with increased hospital mortality (adjusted OR: 1.26-16.59) compared with SCAI shock stage A, as was LD (adjusted OR: 8.2). The SCAI shock classification demonstrated a strong diagnostic performance for hospital mortality (area under the receiver operating characteristic: 0.84), which noticeably increased when LD was incorporated into the model (area under the receiver operating characteristic: 0.90).

CONCLUSIONS

The SCAI shock classification effectively risk-stratifies postoperative CSICU patients for mortality, postoperative complications, and organ dysfunction. Its application could, therefore, be extended to the field of cardiac surgery as a triage tool in postoperative care and as a selection criterion in research.

Standardized Definitions for Cardiogenic Shock Research and Mechanical Circulatory Support Devices: Scientific Expert Panel From the Shock Academic Research Consortium (SHARC)

The Shock Academic Research Consortium is a multi-stakeholder group, including representatives from the US Food and Drug Administration and other government agencies, industry, and payers, convened to develop pragmatic consensus definitions useful for the evaluation of clinical trials enrolling patients with cardiogenic shock, including trials evaluating mechanical circulatory support devices. Several in-person and virtual meetings were convened between 2020 and 2022 to discuss the need for developing the standardized definitions required for evaluation of mechanical circulatory support devices in clinical trials for cardiogenic shock patients. The expert panel identified key concepts and topics by performing literature reviews, including previous clinical trials, while recognizing current challenges and the need to advance evidence-based practice and statistical analysis to support future clinical trials. For each category, a lead (primary) author was assigned to perform a literature search and draft a proposed definition, which was presented to the subgroup. These definitions were further modified after feedback from the expert panel meetings until a consensus was reached. This manuscript summarizes the expert panel recommendations focused on outcome definitions, including efficacy and safety.

Advances in the Management of Cardiogenic Shock

OBJECTIVES

To review a contemporary approach to the management of patients with cardiogenic shock (CS).

DATA SOURCES

We reviewed salient medical literature regarding CS.

STUDY SELECTION

We included professional society scientific statements and clinical studies examining outcomes in patients with CS, with a focus on randomized clinical trials.

DATA EXTRACTION

We extracted salient study results and scientific statement recommendations regarding the management of CS.

DATA SYNTHESIS

Professional society recommendations were integrated with evaluated studies.

CONCLUSIONS

CS results in short-term mortality exceeding 30% despite standard therapy. While acute myocardial infarction (AMI) has been the focus of most CS research, heart failure-related CS now predominates at many centers. CS can present with a wide spectrum of shock severity, including patients who are normotensive despite ongoing hypoperfusion. The Society for Cardiovascular Angiography and Intervention Shock Classification categorizes patients with or at risk of CS according to shock severity, which predicts mortality. The CS population includes a heterogeneous mix of phenotypes defined by ventricular function, hemodynamic profile, biomarkers, and other clinical variables. Integrating the shock severity and CS phenotype with nonmodifiable risk factors for mortality can guide clinical decision-making and prognostication. Identifying and treating the cause of CS is crucial for success, including early culprit vessel revascularization for AMI. Vasopressors and inotropes titrated to restore arterial pressure and perfusion are the cornerstone of initial medical therapy for CS. Temporary mechanical circulatory support (MCS) is indicated for appropriately selected patients as a bridge to recovery, decision, durable MCS, or heart transplant. Randomized controlled trials have not demonstrated better survival with the routine use of temporary MCS in patients with CS. Accordingly, a multidisciplinary team-based approach should be used to tailor the type of hemodynamic support to each individual CS patient's needs based on shock severity, phenotype, and exit strategy.

CHANGES IN VASOACTIVE DRUG REQUIREMENTS AND MORTALITY IN CARDIAC INTENSIVE CARE UNIT PATIENTS

ABSTRACT

Background: The Society for Cardiovascular Angiography and Intervention (SCAI) Shock Classification can define shock severity. We evaluated the vasoactive-inotropic score (VIS) combined with the SCAI Shock Classification for mortality risk stratification. Methods: This was a single-center retrospective cohort analysis including Mayo Clinic cardiac intensive care unit patients from 2007 to 2015. The peak VIS was calculated at 1 and 24 h after cardiac intensive care unit admission. In-hospital mortality was evaluated using multivariable logistic regression. Results: Of 9,916 included patients, vasoactive drugs were used in 875 (8.8%) within 1 h and 2,196 (22.1%) within 24 h. A total of 888 patients (9.0%) died during hospitalization. Patients who required vasoactive drugs within 1 h had higher in-hospital mortality (adjusted odds ratio [OR], 1.30; 95% confidence interval [CI], 1.03-1.65; P = 0.03) and in-hospital mortality rose with the VIS during the first 1 h (adjusted OR per 10 units, 1.22; 95% CI, 1.12-1.33; P < 0.001). The increase in VIS from 1 to 24 h was associated with higher in-hospital mortality (adjusted OR per 10 units, 1.16; 95% CI, 1.10-1.21; P < 0.001). These results were consistent in the 1,067 patients (10.9%) with cardiogenic shock. A gradient of in-hospital mortality was observed according to the VIS at 1 h and the increase in VIS from 1 to 24 h. Conclusions: Higher vasoactive drug requirements portend a higher risk of mortality, particularly a high VIS early after admission. The VIS provides incremental prognostic information beyond the SCAI Shock Classification, emphasizing the continuum of risk that exists across the spectrum of shock severity.

Cardiogenic Shock Classification and Associated Mortality Risk

The Society for Cardiovascular Angiography and Interventions (SCAI) Shock Classification was developed to create standardized language describing the severity of cardiogenic shock (CS). The purposes of this review were to evaluate short-term and long-term mortality rates at each SCAI shock stage for patients with or at risk for CS, which has not been studied previously, and to propose using the SCAI Shock Classification to develop algorithms for clinical status monitoring. A detailed literature search was conducted for articles published from 2019 through 2022 in which the SCAI shock stages were used to assess the mortality risk. In total, 30 articles were reviewed. The SCAI Shock Classification at hospital admission revealed a consistent and reproducible graded association between shock severity and mortality risk. Furthermore, shock severity correlated incrementally with mortality risk even after patients were stratified for diagnosis, treatment modalities, risk modifiers, shock phenotype, and underlying cause. The SCAI Shock Classification system can be used to evaluate mortality across populations of patients with or at risk for CS including those with different causes, shock phenotypes, and comorbid conditions. We propose an algorithm that uses clinical parameters incorporating the SCAI Shock Classification into the electronic health record to continually reassess and reclassify the presence and severity of CS across time throughout hospitalization. The algorithm has the potential to alert the care team and a CS team, leading to earlier recognition and stabilization of the patient, and may facilitate the use of treatment algorithms and prevent CS deterioration, leading to improved outcomes.

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.

Differences in Outcome of Patients with Cardiogenic Shock Associated with In-Hospital or Out-of-Hospital Cardiac Arrest

Cardiogenic Shock (CS) complicated by in-hospital (IHCA) or out-of-hospital cardiac arrest (OHCA) has a poor outcome. However, studies regarding the prognostic differences between IHCA and OHCA in CS are limited. In this prospective, observational study, consecutive patients with CS were included in a monocentric registry from June 2019 to May 2021. The prognostic impact of IHCA and OHCA on 30-day all-cause mortality was tested within the entire group and in the subgroups of patients with acute myocardial infarction (AMI) and coronary artery disease (CAD). Statistical analyses included univariable t-test, Spearman's correlation, Kaplan-Meier analyses, as well as uni- and multivariable Cox regression analyses. A total of 151 patients with CS and cardiac arrest were included. IHCA on ICU admission was associated with higher 30-day all-cause mortality compared to OHCA in univariable COX regression and Kaplan-Meier analyses. However, this association was solely driven by patients with AMI (77% vs. 63%; log rank p = 0.023), whereas IHCA was not associated with 30-day all-cause mortality in non-AMI patients (65% vs. 66%; log rank p = 0.780). This finding was confirmed in multivariable COX regression, in which IHCA was solely associated with higher 30-day all-cause mortality in patients with AMI (HR = 2.477; 95% CI 1.258-4.879; p = 0.009), whereas no significant association could be seen in the non-AMI group and in the subgroups of patients with and CAD. CS patients with IHCA showed significantly higher all-cause mortality at 30 days compared to patients with OHCA. This finding was primarily driven by a significant increase in all-cause mortality at 30 days in CS patients with AMI and IHCA, whereas no difference could be seen when differentiated by CAD.

Mechanical Circulatory Support Devices in Acute Myocardial Infarction-Cardiogenic Shock: Current Studies and Future Directions

Cardiogenic shock (CS) caused by acute myocardial infarction (AMI) accounts for most deaths in the population with AMI and continues to be associated with high short-term mortality. Several temporary mechanical circulatory support (MCS) devices have been developed to treat CS and studied in randomized controlled trials (RCTs) of patients with AMI-CS. Unfortunately, none of these RCTs has demonstrated an improvement in survival with temporary MCS in AMI-CS. Potential reasons for these negative results in RCTs are numerous and reflect the challenges of enrolling critically ill patients with CS. Researchers have used observational study designs to provide insights about outcomes associated with the use of temporary MCS in AMI-CS. These observational studies have yielded conflicting results, in some cases contrary to the results of RCTs. Several limitations pertinent to both RCTs and observational analyses, mostly relating to selection bias and failure to consider unmeasured confounding variables and population heterogeneity, preclude drawing strong inferences regarding the effects of temporary MCS on survival in populations with AMI-CS. Understanding these limitations is essential to correctly interpreting the literature regarding temporary MCS to treat AMI-CS and is necessary to inform the design of future studies that will potentially provide stronger evidence. Optimally matching temporary MCS devices to the needs of individual patients with AMI-CS will presumably be more successful than indiscriminate application in unselected patients. In this review, we discuss the existing literature on temporary MCS to treat AMI-CS and describe the specific challenges that must be overcome to develop an improved evidence base for guiding clinical practice.

Time from Admission to Right Heart Catheterization in Cardiogenic Shock Patients

Cardiogenic shock (CS) presents with a complex spectrum of low output states, which can be provoked by Acute Coronary Syndrome (ACS) or Acute Decompensated Heart Failure (ADHF). Its management includes hemodynamic assessment via right heart catheterization (RHC). Herein, we describe the timing of RHC based on the etiology and severity of CS as defined by the Society of Cardiovascular Angiography & Interventions (SCAI) Shock Classification. We performed a single-center retrospective analysis of patients admitted with CS secondary to ACS or ADHF from January 7, 2018 to June 30, 2020 at the University of Iowa Hospitals and Clinics. Among the 647 patients admitted, 249 patients had RHC during their admission. Of those, 51 had underlying ACS and 198 had ADHF. The overall time from admission to invasive hemodynamic assessment was 2.73 days. The mean time for SCAI-A was 3.6 ± 2.8 days, SCAI-B 3.7 ± 3.7 days, SCAI-C 2.6 ± 3.0 days, SCAI-D 2.5 ± 4.1 days, and SCAI-E 1.3 ± 2.1 days. The linear regression model showed that RHC was performed earlier in patients with worse hemodynamics evaluated by Cardiac Power Output (CPO) (Coefficient 0.14, R- squared 0.01, P = 0.03). Hemodynamic parameters showed that high PAPi, RVSWi, and Cardiac Power Output during admission predicted low in-hospital mortality (P < 0.01). RHC was performed earlier in more critically ill patients. Patients with CS in the setting of ACS underwent RHC significantly earlier than those with ADHF.

Cardiogenic shock severity and mortality in patients receiving venoarterial extracorporeal membrane oxygenator support

AIMS

Shock severity predicts mortality in patients with cardiogenic shock (CS). We evaluated the association between pre-cannulation Society for Cardiovascular Angiography and Intervention (SCAI) shock classification and mortality among patients receiving venoarterial (VA) extracorporeal membrane oxygenation (ECMO) support for CS.

METHODS AND RESULTS

We included Extracorporeal Life Support Organization (ELSO) Registry patients from 2010 to 2020 who received VA ECMO for CS. SCAI shock stage was assigned based on hemodynamic support requirements prior to ECMO initiation. In-hospital mortality was analyzed using multivariable logistic regression. We included 12 106 unique VA ECMO patient runs with a median age of 57.9 (interquartile range: 46.8, 66.1) years and 31.8% were females; 3472 (28.7%) were post-cardiotomy. The distribution of SCAI shock stages at ECMO initiation was: B, 821 (6.8%); C, 7518 (62.1%); D, 2973 (24.6%); and E, 794 (6.6%). During the index hospitalization, 6681 (55.2%) patients died. In-hospital mortality increased incrementally with SCAI shock stage (adjusted OR: 1.24 per SCAI shock stage, 95% CI: 1.17-1.32, P < 0.001): B, 47.5%; C, 52.8%; D, 60.8%; E, 65.1%. A higher SCAI shock stage was associated with increased in-hospital mortality in key subgroups, although the SCAI shock classification was only predictive of mortality in non-surgical (medical) CS and not in post-cardiotomy CS.

CONCLUSION

The severity of shock prior to cannulation is a strong predictor of in-hospital mortality in patients receiving VA ECMO for CS. Using the pre-cannulation SCAI shock classification as a risk stratification tool can help clinicians refine prognostication for ECMO recipients and guide future investigations to improve outcomes.

Impact of Lactate on 30-Day All-Cause Mortality in Patients with and without Out-of-Hospital Cardiac Arrest Due to Cardiogenic Shock

In patients with cardiogenic shock (CS) due to myocardial infarction, elevated lactate levels are known to be negative predictors. Studies regarding the prognostic impact in patients with CS complicated by out-of-hospital cardiac arrest (OHCA) are limited. Two hundred and sixty-three consecutive patients with CS were included. The prognostic value of lactate on days 1, 2, 3, 4 and 8 was tested stratified by OHCA and non-OHCA. Statistical analyses included the univariable t-test, Spearman's correlation, C-statistics, Kaplan-Meier analyses, as well as multivariable mixed analysis of variance (ANOVA) and Cox proportional regression analyses. The primary endpoint of all-cause mortality occurred in 49.4% of the non-OHCA group and in 63.4% of the OHCA group. Multivariable regression models showed an association of lactate values with 30-day all-cause mortality in the non-OHCA (p = 0.024) and OHCA groups (p = 0.001). In Kaplan-Meier analyses, patients with lactate levels ≥ 4 mmol/L (log-rank p = 0.001) showed the highest risk for 30-day all-cause mortality in the non-OHCA as well as in the OHCA group. However, in C-statistics lactate on days 1 and 8 had a better discrimination for 30-day all-cause mortality in the OHCA group compared to the non-OHCA group. In conclusion, patients presenting with CS lactate levels showed a good prognostic performance, with and without OHCA. Especially, lactate levels on days 1 and 8 were more accurate in the discrimination for all-cause mortality in CS-patients with OHCA.

Contemporary Management of Concomitant Cardiac Arrest and Cardiogenic Shock Complicating Myocardial Infarction

Cardiogenic shock (CS) and cardiac arrest (CA) are the most life-threatening complications of acute myocardial infarction. Although there is a significant overlap in the pathophysiology with approximately half the patients with CS experiencing a CA and approximately two-thirds of patients with CA developing CS, comprehensive guideline recommendations for management of CA + CS are lacking. This paper summarizes the current evidence on the incidence, pathophysiology, and short- and long-term outcomes of patients with acute myocardial infarction complicated by concomitant CA + CS. We discuss the hemodynamic factors and unique challenges that need to be accounted for while developing treatment strategies for these patients. A summary of expert-based step-by-step recommendations to the approach and treatment of these patients, both in the field before admission and in-hospital management, are presented.

Advances in the Staging and Phenotyping of Cardiogenic Shock: Part 1 of 2

Cardiogenic shock (CS) is a heterogeneous syndrome reflecting a broad spectrum of shock severity, diverse etiologies, variable cardiac function, different hemodynamic trajectories, and concomitant organ dysfunction. These factors influence the clinical presentation, management, response to therapy, and outcomes of CS patients, necessitating a tailored approach to care. To better understand the variability inherent to CS populations, recent algorithms for staging the severity of CS have been described and validated. This paper is part 1 of a 2-part state-of-the-art review. In this first article, we consider the context for clinical staging and stratification in CS with a focus on established severity staging systems for CS and their use for risk stratification and clinical care. We describe the use of staging for predicting outcomes in populations with or at risk for CS, including risk modifiers that provide more nuanced risk stratification, and highlight how these approaches may allow individualized care.

Application of the SCAI classification to admission of patients with cardiogenic shock: Analysis of a tertiary care center in a middle-income country

Aims

The Society of Cardiovascular Angiography and Interventions (SCAI) shock stages have been applied and validated in high-income countries with access to advanced therapies. We applied the SCAI scheme at the time of admission in order to improve the risk stratification for 30-day mortality in a retrospective cohort of patients with STEMI in a middle-income country hospital at admission.

Methods

This is a retrospective cohort study, we analyzed 7,143 ST-segment elevation myocardial infarction (STEMI) patients. At admission, patients were stratified by the SCAI shock stages. Multivariate analysis was used to assess the association between SCAI shock stages to 30-day mortality.

Results

The distribution of the patients across SCAI shock stages was 82.2%, 9.3%, 1.2%, 1.5%, and 0.8% to A, B, C, D, and E, respectively. Patients with SCAI stages C, D, and E were more likely to have high-risk features. There was a stepwise significant increase in unadjusted 30-day mortality across the SCAI shock stages (6.3%, 8.4%, 62.4%, 75.2% and 88.3% for A, B, C, D and E, respectively; P < 0.0001, C-statistic, 0.64). A trend toward a lower 30-day survival probability was observed in the patients with advanced CS (30.3, 15.4%, and 8.3%, SCAI shock stages C, D, and E, respectively, Log-rank P-value <0.0001). After multivariable adjustment, SCAI shock stages C, D, and E were independently associated with an increased risk of 30-day death (hazard ratio 1.42 [P = 0.02], 2.30 [P<0.0001], and 3.44 [P<0.0001], respectively).

Conclusion

The SCAI shock stages applied in patients con STEMI at the time of admission, is a useful tool for risk stratification in patients across the full spectrum of CS and is a predictor of 30-day mortality.

Echocardiographic Characteristics of Cardiogenic Shock Patients with and Without Cardiac Arrest

BACKGROUND

Cardiac arrest (CA) is associated with worse outcomes in patients with cardiogenic shock (CS). To better understand the contribution of CA on CS, we evaluated transthoracic echocardiography (TTE) parameters in CS patients with and without CA. Methods: We retrospectively identified CS patients with a TTE performed near cardiac intensive care unit admission between 2007 to 2018. We compared TTE measurements of left ventricular (LV) and right ventricular (RV) function in patients with and without CA. The primary outcome was all-cause in-hospital mortality, as determined using multivariable logistic regression. Results: We included 1085 patients, 35% of whom had CA. Median age was 70 years and 37% were females. CA patients had higher severity of illness, more invasive mechanical ventilation and greater vasopressor/inotrope use. In-hospital mortality was 31% and was higher in CA patients (45% vs. 23%, p <0.001). Although LV ejection fraction (LVEF) was similar (35% vs. 37%, p = 0.05), CA patients had lower cardiac index, mitral valve E wave peak velocity, E/A ratio and E/e' ratio. TTE variables that were associated with hospital mortality varied, among patients with CA, these included measures of RV pressure and function and among patients without CA, these included parameters reflecting LV systolic function. Conclusions: Doppler assessments of RV systolic dysfunction were the strongest TTE predictors of hospital mortality in CS patients with CA, unlike CS patients without CA in whom LV systolic function was more important. This emphasizes the importance of RV assessment for mortality risk stratification after CA.

Epidemiology and Outcomes of Patients Readmitted to the Intensive Care Unit After Cardiac Intensive Care Unit Admission

Readmission to the intensive care unit (ICU) during the index hospitalization is associated with poor outcomes in medical or surgical ICU survivors. Little is known about critically ill patients with acute cardiovascular conditions cared for in a cardiac intensive care unit (CICU). We sought to describe the incidence, risk factors, and outcomes of all ICU readmissions in patients who survived to CICU discharge. We retrospectively reviewed Mayo Clinic patients from 2007 to 2015 who survived the index CICU admission and identified patients with a second ICU stay during their index hospitalization; these patients were categorized as ICU transfers (patients who went directly from the CICU to another ICU) or ICU readmissions (patients initially transferred from the CICU to the ward, and then back to an ICU). Among 9,434 CICU survivors (mean age 67 years), 138 patients (1.5%) had a second ICU stay during the index hospitalization: 60 ICU transfers (0.6%) and 78 ICU readmissions (0.8%). The most common indications for ICU readmission were respiratory failure and procedure/surgery. On multivariable modeling, respiratory failure, severe acute kidney injury, and Charlson Comorbidity Index at the time of discharge from the index ICU stay were associated with ICU readmission. Death during the first ICU readmission (n = 78) occurred in 7.7% of patients. In-hospital mortality was higher for patients with a second ICU stay. In conclusion, few CICU survivors have a second ICU stay during their index hospitalization; these patients are at a higher risk of in-hospital and 1-year mortality. Respiratory failure, severe acute kidney injury, and higher co-morbidity burden identify CICU survivors at elevated risk of ICU readmission.

Outcomes Associated With Cardiac Arrest in Patients in the Cardiac Intensive Care Unit With Cardiogenic Shock

Cardiac arrest (CA) is common and has been associated with adverse outcomes in patients with cardiogenic shock (CS). We sought to determine the prevalence, patient characteristics, and outcomes of CA in cardiovascular intensive care unit patients with CS. We queried cardiovascular intensive care unit admissions from 2007 to 2018 with an admission diagnosis of CS and compared patients with and without CA. Temporal trends were assessed using linear regression. The primary and secondary outcomes of in-hospital and 1-year mortality were analyzed using logistic regression and Cox proportional-hazards analysis, respectively. We included 1,498 patients, and CA was present in 510 patients (34%), with 258 (50.6% of patients with CA) having ventricular fibrillation (VF). Mean age was 68 ± 14 years, and 37% were females. The prevalence of CA decreased over time (from 43% in 2007 to 24% in 2018, p <0.001). Hospital mortality was 33.3% and decreased over time in patients without CA (from 30% in 2007 to 22% in 2018, p = 0.05), but not in patients with CA (p = 0.71). CA was associated with a higher risk of hospital mortality (51.0% vs 24.2%, adjusted odds ratio 2.15, 95% confidence interval [CI] 1.52 to 3.05, p <0.001), with no difference between VF CA and non-VF CA (p = 0.64). CA was associated with higher 1-year mortality (adjusted hazard ratio 1.53, 95% CI 1.24 to 1.89, p <0.001). In conclusion, CA is present in 1 of 3 of CS hospitalizations and confers a substantially higher risk of hospital and 1-year mortality with no improvement during our 12-year study period contrary to prevailing trends.

Peripheral blood neutrophil-to-lymphocyte ratio is associated with mortality across the spectrum of cardiogenic shock severity

PURPOSE

To evaluate the association between the neutrophil-to-lymphocyte ratio (NLR) and mortality across the cardiogenic shock (CS) severity spectrum, defined using the Society of Cardiovascular Interventions and Angiography (SCAI) shock stages.

MATERIALS AND METHODS

We retrospectively analyzed cardiac intensive care unit (CICU) patients between 2007 and 2015. Predictors of in-hospital mortality were analyzed using logistic regression.

RESULTS

We included 8280 patients aged 67.3 ± 15.2 years (37.2% females). Elevated NLR (≥7) was present in 45% of patients. NLR increased with worsening SCAI stage and was associated with higher in-hospital mortality in shock stages A to C (all p < 0.001). After multivariable adjustment, NLR remained associated with higher in-hospital mortality (adjusted odds ratio 1.05 per 3.5 NLR units, 95% CI 1.03-1.08, p < 0.001), with an optimal cut-off of ≥7 (in-hospital mortality 13.1% vs. 4.1%, adjusted odds ratio 1.44, 95% CI 1.14-1.81, p = 0.002). Patients in SCAI stage A or B with NLR ≥7 had higher in-hospital mortality than patients in SCAI stage B or C with NLR <7, respectively.

CONCLUSIONS

Elevated NLR is associated with higher in-hospital mortality in CICU patients with or at risk for CS, emphasizing the importance of systemic inflammation as a determinant of outcomes in CS patients.

The landscape of cardiogenic shock: epidemiology and current definitions

PURPOSE OF REVIEW

Despite novel technologies for treating shock patients, cardiogenic shock mortality remains high. Trends of cardiogenic shock associated with acute myocardial infarction (AMI) have previously been described, though little is known about cardiogenic shock resulting from other causes, which has progressively been documented as a distinct entity from AMI-cardiogenic shock. Herein, we review the evolving epidemiology, novel classification schema, and future perspectives of cardiogenic shock.

RECENT FINDINGS

While AMI or mechanical complications of AMI are the most common causes, the incidence of etiologies of cardiogenic shock not related to AMI, particularly acute on chronic heart failure, may be increasing, with a growing burden of noncoronary structural heart disease.

SUMMARY

Mortality in cardiogenic shock remains high. Overall, these findings highlight the need to address the lack of effective treatments in this field, particularly for cardiogenic shock caused by diseases other than AMI. Novel classification systems may facilitate cardiogenic shock research.

Echocardiographic left ventricular stroke work index: An integrated noninvasive measure of shock severity

Background

Echocardiographic findings vary with shock severity, as defined by the Society for Cardiovascular Angiography and Intervention (SCAI) shock stage. Left ventricular stroke work index (LVSWI) measured by transthoracic echocardiography (TTE) can predict mortality in the cardiac intensive care unit (CICU). We sought to determine whether LVSWI could refine mortality risk stratification by the SCAI shock classification in the CICU.

Methods

We included consecutive CICU patients from 2007 to 2015 with TTE data available to calculate the LVSWI, specifically the mean arterial pressure, stroke volume index and medial mitral E/e’ ratio. In-hospital mortality as a function of LVSWI was evaluated across the SCAI shock stages using logistic regression, before and after multivariable adjustment.

Results

We included 3635 unique CICU patients, with a mean age of 68.1 ± 14.5 years (36.5% females); 61.1% of patients had an acute coronary syndrome. The LVSWI progressively decreased with increasing shock severity, as defined by increasing SCAI shock stage. A total of 203 (5.6%) patients died during hospitalization, with higher in-hospital mortality among patients with lower LVSWI (adjusted OR 0.66 per 10 J/m2 higher) or higher SCAI shock stage (adjusted OR 1.24 per each higher stage). A LVSWI <33 J/m2 was associated with higher adjusted in-hospital mortality, particularly among patients with shock (SCAI stages C, D and E).

Conclusions

The LVSWI by TTE noninvasively characterizes the severity of shock, including both systolic and diastolic parameters, and can identify low-risk and high-risk patients at each level of clinical shock severity.

Echocardiographic Correlates of Mortality Among Cardiac Intensive Care Unit Patients With Cardiogenic Shock

BACKGROUND

Prior studies have shown worse outcomes in patients with cardiogenic shock (CS) who have reduced left ventricular ejection fraction (LVEF), but the association between other transthoracic echocardiogram (TTE) findings and mortality in CS patients remains uncertain. We hypothesized that Doppler TTE measurements would outperform LVEF for risk stratification.

METHODS

Retrospective analysis of cardiac intensive care unit patients with an admission diagnosis of CS and a TTE within 1 day of admission. Hospital survivors and inpatient deaths were compared, and multivariable logistic regression was used to analyze the associations between TTE variables and hospital mortality.

RESULTS

We included 1,085 patients, with a median age of 69.5 (59.6, 77.5) years; 37% were females and 62% had an acute coronary syndrome. Most patients (66%) had moderate or severe left ventricular (LV) systolic dysfunction, and 48% had moderate or severe right ventricular (RV) systolic dysfunction. Hospital mortality occurred in 31%, and inpatient deaths had a lower median LVEF (29% vs. 35%, P < 0.001). Patients with mild or no LV or RV dysfunction were at lower risk of adjusted hospital mortality (P < 0.01). The LV outflow tract (LVOT) velocity-time integral (VTI) was the single best predictor of hospital mortality. After multivariable adjustment, both the LVEF and LVOT VTI remained strongly associated with hospital mortality (P < 0.001).

CONCLUSIONS

Early comprehensive Doppler TTE can provide important prognostic insights in CS patients, highlighting its potential utility in clinical practice. The LVOT VTI, reflecting forward flow, is an important measurement to obtain on bedside TTE.

Society for Cardiovascular Angiography and Intervention Shock Classification Predicts Mortality After Out-of-Hospital Cardiac Arrest

BACKGROUND

Shock is common in patients resuscitated from out-of-hospital-cardiac arrest (OHCA). Shock severity can be classified using the Society for Cardiovascular Angiography and Intervention (SCAI) Shock Classification. We aimed to examine the association of SCAI Shock Stage with in-hospital mortality and neurological outcome in comatose OHCA patients undergoing targeted temperature management (TTM).

METHODS

This study included 213 comatose adult patients who underwent TTM after OHCA between January 2007 and December 2017. SCAI shock stage (A through E) was assigned using data from the first 24 hours, with shock defined as SCAI shock stage C/D/E. Good neurological outcome was defined as a modified Rankin Scale (mRS) less than 3.

RESULTS

In-hospital mortality was higher in the 144 (67.6%) patients with shock (46.5% v. 23.2%, unadjusted OR 2.88, 95% CI 1.51-5.51, p = 0.001). After multivariable adjustment, each SCAI shock stage was incrementally associated with an increased risk of in-hospital mortality (adjusted OR 1.80 per stage, 95% CI 1.20-2.71, p = 0.003). Good neurological outcome was less likely in patients with shock (31.9% vs. 53.6%, unadjusted OR 0.41, 95% CI 0.23-0.73, p = 0.002) and a higher SCAI shock stage was incrementally associated with a lower likelihood of good neurological outcome after multivariable adjustment (adjusted OR 0.67 per stage, 95% CI 0.48-0.93, p = 0.015).

CONCLUSION

Higher shock severity, defined using the SCAI Shock Classification, was associated with increased in-hospital mortality and a lower likelihood of good neurological outcome in OHCA patients treated with TTM.

Validation of cardiogenic shock phenotypes in a mixed cardiac intensive care unit population

BACKGROUND

Proposed phenotypes have recently been identified in cardiogenic shock (CS) populations using unsupervised machine learning clustering methods. We sought to validate these phenotypes in a mixed cardiac intensive care unit (CICU) population of patients with CS.

METHODS

We included Mayo Clinic CICU patients admitted from 2007 to 2018 with CS. Agnostic K means clustering was used to assign patients to three clusters based on admission values of estimated glomerular filtration rate, bicarbonate, alanine aminotransferase, lactate, platelets, and white blood cell count. In-hospital mortality and 1-year mortality were analyzed using logistic regression and Cox proportional-hazards models, respectively.

RESULTS

We included 1498 CS patients with a mean age of 67.8 ± 13.9 years, and 37.1% were females. The acute coronary syndrome was present in 57.3%, and cardiac arrest was present in 34.0%. Patients were assigned to clusters as follows: Cluster 1 (noncongested), 603 (40.2%); Cluster 2 (cardiorenal), 452 (30.2%); and Cluster 3 (hemometabolic), 443 (29.6%). Clinical, laboratory, and echocardiographic characteristics differed across clusters, with the greatest illness severity in Cluster 3. Cluster assignment was associated with in-hospital mortality across subgroups. In-hospital mortality was higher in Cluster 3 (adjusted odds ratio [OR]: 2.6 vs. Cluster 1 and adjusted OR: 2.0 vs. Cluster 2, both p < 0.001). Adjusted 1-year mortality was incrementally higher in Cluster 3 versus Cluster 2 versus Cluster 1 (all p < 0.01).

CONCLUSIONS

We observed similar phenotypes in CICU patients with CS as previously reported, identifying a gradient in both in-hospital and 1-year mortality by cluster. Identifying these clinical phenotypes can improve mortality risk stratification for CS patients beyond standard measures.

Shock Severity Assessment in Cardiac Intensive Care Unit Patients With Sepsis and Mixed Septic-Cardiogenic Shock

We sought to validate the Society for Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock classification for mortality risk stratification in patients with sepsis and concomitant cardiovascular disease or mixed septic-cardiogenic shock. We conducted a single-center retropective cohort study of cardiac intensive care unit patients with an admission diagnosis of sepsis. We used clinical, vital sign, and laboratory data during the first 24 hours after admission to assign SCAI shock stage. We included 605 patients with a median age of 69.4 years (interquartile range, 57.9 to 79.8 years), 222 of whom (36.7%) were female. Acute coronary syndrome or heart failure was present in 480 patients (79.3%), and cardiogenic shock or cardiac arrest was present in 271 patients (44.8%). The median day 1 Sequential Organ Failure Assessment (SOFA) cardiovascular subscore was 1.5 (interquartile range, 1 to 4), and the admission SCAI shock stage distribution was stage B, 40.7% (246); stage C, 19.3% (117); stage D, 32.9% (199); and stage E, 7.1% (43). In-hospital mortality occurred in 177 of the 605 patients (29.3%) and increased incrementally with higher SCAI shock stage. After multivariable adjustment, admission SCAI shock stage was associated with in-hospital mortality (adjusted odds ratio per stage, 1.46; 95% CI, 1.14 to 1.88; P=.003). Admission SCAI shock stage had higher discrimination for in-hospital mortality than the day 1 SOFA cardiovascular subscore (area under the receiver operating characteristic curve, 0.68 vs 0.64; P=.04 by the DeLong test). Admission SCAI shock stage was associated with 1-year mortality (adjusted hazard ratio per stage, 1.19; 95% CI, 1.03 to 1.37; P=.02). The SCAI shock classification provides improved mortality risk stratification over the day 1 SOFA cardiovascular subscore in cardiac intensive care unit patients with sepsis and concomitant cardiovascular disease or mixed septic-cardiogenic shock.

Acute Myocardial Infarction and Cardiogenic Shock Interventional Approach to Management in the Cardiac Catheterization Laboratories

Despite advances in early reperfusion and a technologic renaissance in the space of Mechanical Circulatory Support (MCS), Cardiogenic Shock (CS) remains the leading cause of in-hospital mortality following Acute Myocardial Infarction (AMI). Given the challenges inherent to conducting adequately powered randomized controlled trials in this time-sensitive, hemodynamically complex, and highly lethal syndrome, treatment recommendations have been derived from AMI patients without shock. In this review, we aimed to (1) examine the pathophysiology and the new classification system for CS; (2) provide a comprehensive, evidence-based review for best practices for interventional management of AMI-CS in the cardiac catheterization laboratory; and (3) highlight the concept of how frailty and geriatric syndromes can be integrated into the decision process and where medical futility lies in the spectrum of AMI-CS care. Management strategies in the cardiac catheterization laboratory for CS include optimal vascular access, periprocedural antithrombotic therapy, culprit lesion versus multi-vessel revascularization, selective utilization of hemodynamic MCS tailored to individual shock hemometabolic profiles, and management of cardiac arrest. Efforts to advance clinical evidence for patients with CS should be concentrated on (1) the coordination of multi-center registries; (2) development of pragmatic clinical trials designed to evaluate innovative therapies; (3) establishment of multidisciplinary care models that will inform quality care and improve clinical outcomes.

Laboratory Markers of Acidosis and Mortality in Cardiogenic Shock: Developing a Definition of Hemometabolic Shock

BACKGROUND

Acidosis and higher lactate predict worse outcomes in cardiogenic shock (CS) patients. We sought to determine whether overall acidosis severity on admission predicted in-hospital mortality in CS patients.

METHODS

This retrospective descriptive analysis included CS patients admitted to a single academic tertiary cardiac intensive care unit from 2007 to 2015. Admission arterial pH, base excess, and anion gap values were used to generate a Composite Acidosis Score (range 0-5, with a score ≥2 defining Severe Acidosis). Adjusted in-hospital mortality was analyzed using multivariable logistic regression.

RESULTS

We included 1,065 patients with median age of 68.9 (59.0, 77.2) years (36.4% females). Concomitant diagnoses included cardiac arrest in 38.1% and acute coronary syndrome in 59.1%. Severe Acidosis was present in 35.2%, and these patients had worse shock and more organ failure. In-hospital mortality occurred in 34.1% and was higher among patients with Severe Acidosis (54.9% vs. 22.4%, adjusted odds ratio [OR] 2.01, 95% CI 1.43-2.83, P < 0.001). Increasing Composite Acidosis Score was associated with higher in-hospital mortality (adjusted OR 1.25 per point, 95% CI 1.11-1.40, P < 0.001). Severe Acidosis was associated with higher hospital mortality at every level of shock severity and organ failure (all P < 0.05). Admission lactate level had equivalent discrimination for in-hospital mortality as the Composite Acidosis Score (0.69 vs. 0.66; P = 0.32 by De Long test).

CONCLUSION

Given its incremental association with higher in-hospital mortality among CS patients beyond shock severity and organ failure, we propose Severe Acidosis as a marker of hemometabolic shock. Lactate levels performed as well as a composite measure of acidosis for predicting mortality.

Comparison of risk prediction models in infarct-related cardiogenic shock

AIMS

Several prediction models have been developed to allow accurate risk assessment and provide better treatment guidance in patients with infarct-related cardiogenic shock (CS). However, comparative data between these models are still scarce. The objective of the study is to externally validate different risk prediction models in infarct-related CS and compare their predictive value in the early clinical course.

METHODS AND RESULTS

The Simplified Acute Physiology Score (SAPS) II Score, the CardShock score, the IABP-SHOCK II score, and the Society for Cardiovascular Angiography and Intervention (SCAI) classification were each externally validated in a total of 1055 patients with infarct-related CS enrolled into the randomized CULPRIT-SHOCK trial or the corresponding registry. The primary outcome was 30-day all-cause mortality. Discriminative power was assessed by comparing the area under the curves (AUC) in case of continuous scores. In direct comparison of the continuous scores in a total of 161 patients, the IABP-SHOCK II score revealed best discrimination [area under the curve (AUC = 0.74)], followed by the CardShock score (AUC = 0.69) and the SAPS II score, giving only moderate discrimination (AUC = 0.63). All of the three scores revealed acceptable calibration by Hosmer-Lemeshow test. The SCAI classification as a categorical predictive model displayed good prognostic assessment for the highest risk group (Stage E) but showed poor discrimination between Stages C and D with respect to short-term-mortality.

CONCLUSION

Based on the present findings, the IABP-SHOCK II score appears to be the most suitable of the examined models for immediate risk prediction in infarct-related CS. Prospective evaluation of the models, further modification, or even development of new scores might be necessary to reach higher levels of discrimination.

Biventricular Function and Shock Severity Predict Mortality in Cardiac ICU Patients

BACKGROUND

Ventricular function, including left ventricular systolic dysfunction (LVSD), right ventricular systolic dysfunction (RVSD), and biventricular dysfunction (BVD), contribute to shock in cardiac ICU (CICU) patients, but the prognostic usefulness remains unclear.

RESEARCH QUESTION

Do patients with ventricular dysfunction have higher mortality at each Society for Cardiovascular Angiography and Intervention (SCAI) shock stage?

STUDY DESIGN AND METHODS

We identified patients in the CICU admitted with available echocardiography data. LVSD was defined as left ventricular ejection fraction < 40%, RVSD as moderate or greater systolic dysfunction by semiquantitative measurement, and BVD as the presence of both. Multivariate logistic regression determined the relationship between ventricular dysfunction and adjusted in-hospital mortality as a function of SCAI stage.

RESULTS

The study population included 3,158 patients with a mean ± SD age of 68.2 ± 14.6 years, of which 51.8% had acute coronary syndromes. LVSD was present in 22.3%, RVSD in 11.8%, and BVD in 16.4%. After adjustment for SCAI shock stage, no difference in in-hospital mortality was found between patients with LVSD or RVSD and those without ventricular dysfunction (P > .05), but BVD was associated independently with higher in-hospital mortality (adjusted hazard ratio, 1.815; 95% CI, 1.237-2.663; P = .0023). The addition of ventricular dysfunction to the SCAI staging criteria increased discrimination for hospital mortality (area under the receiver operating characteristic curve, 0.784 vs 0.766; P < .001).

INTERPRETATION

Among patients admitted to the CICU, only BVD was associated independently with higher hospital mortality. The addition of echocardiography assessment to the SCAI shock criteria may facilitate improved clinical risk stratification.

Lingua Franca of Cardiogenic Shock: Speaking the Same Language

Cardiogenic shock has remained a vexing clinical problem over the last 20 years despite progressive development of increasingly capable percutaneous mechanical circulatory support devices. It is increasingly clear that the published trials of various percutaneous mechanical circulatory support devices have compared heterogenous populations of cardiogenic shock patients, and therefore have not yielded a single result where one approach improved survival. To classify patients, various risk scores such as the CARDSHOCK and IABP-Shock-II scores have been developed and validated but they have not been broadly applied. The Society for Cardiac Angiography and Intervention Expert Consensus on Classification of Cardiogenic Shock has been widely studied since its publication in 2019, and is reviewed at length. In particular, there have been numerous validation studies done and these are reviewed. Finally, the directions for future research are reviewed.

Describing and Classifying Shock: Recent Insights

Cardiogenic shock continues to present a daunting challenge to clinicians, despite an increasing array of percutaneous mechanical circulatory support devices. Mortality for cardiogenic shock has not changed meaningfully in more than 20 years. There have been many attempts to generate risk scores or frameworks to evaluate cardiogenic shock and optimize the use of resources and assist with prognostication. These include the Intra-Aortic Balloon Pump in Cardiogenic Shock (IABP-SHOCK) II risk score, the CardShock score and the new CLIP biomarker score. This article reviews the Society for Cardiac Angiography and Interventions (SCAI) classification of cardiogenic shock and subsequent validation studies. The SCAI classification is simple for clinicians to use as it is based on readily available information and can be adapted depending on the data set that can be accessed. The authors consider the future of the field. Underlying all these efforts is the hope that a better understanding and classification of shock will lead to meaningful improvements in mortality rates.

Managing the first 120 min of cardiogenic shock: from resuscitation to diagnosis

PURPOSE OF REVIEW

Cardiogenic shock continues to carry a high mortality, and recent randomized trials have not identified novel therapies that improve survival. Early optimization of patients with confirmed or suspected cardiogenic shock is crucial, as patients can quickly transition from a hemodynamic shock state to a treatment-resistant hemometabolic shock state, where accumulated metabolic derangements trigger a self-perpetuating cycle of worsening shock.

RECENT FINDINGS

We describe a structured ABCDE approach involving stabilization of the airway, breathing and circulation, followed by damage control and etiologic assessment. Respiratory failure is common and many cardiogenic shock patients require invasive mechanical ventilation. Norepinephrine is titrated to restore mean arterial pressure and dobutamine is titrated to restore cardiac output and organ perfusion. Echocardiography is essential to identify potential causes and characterize the phenotype of cardiogenic shock. Coronary angiography is usually indicated, particularly when acute myocardial ischemia is suspected, followed by culprit-vessel revascularization if indicated. An invasive hemodynamic assessment can clarify whether temporary mechanical circulatory support is necessary.

SUMMARY

Early stabilization of hemodynamics and end-organ function is necessary to achieve best outcomes in cardiogenic shock. Using a structured approach tailored to initial cardiogenic shock resuscitation may help to demonstrate benefit from novel therapies in the future.

Influence of intra-aortic balloon pump on mortality as a function of cardiogenic shock severity

BACKGROUND

Randomized studies of intra-aortic balloon pump (IABP) in cardiogenic shock (CS) have focused exclusively on patients with acute coronary syndromes (ACS) without stratification according to shock severity. We examined the association between IABP and mortality in CS patients across the Society for Cardiovascular Angiography and Intervention (SCAI) shock stages.

METHODS

We included cardiac intensive care unit patients admitted from 2007 to 2015 with CS from any etiology. In-hospital mortality associated with IABP was examined in each SCAI shock stage. Multivariable logistic regression was performed using inverse probability of treatment weighting (IPTW) to determine the association between IABP and in-hospital mortality.

RESULTS

We included 934 patients, with a mean age of 68 ± 14 years; 60% had ACS. The distribution of SCAI shock stages was: B, 41%; C, 13%; D, 38%; E, 8%. In-hospital mortality was lower in the 39% of patients who received IABP (27% vs. 43%, adjusted OR with IABP after IPTW 0.53, 95% CI 0.40-0.72, p < .0001). IABP use was associated with lower crude in-hospital mortality in each SCAI shock stage (all p < .05, except p = .08 in SCAI shock stage E). We did not observe any significant heterogeneity in the association between IABP use and in-hospital mortality as a function of SCAI shock stage.

CONCLUSIONS

IABP use was associated with substantially lower in-hospital mortality in patients with CS, without differences in this effect across the SCAI shock stages. Future studies should account for the severity and etiology of shock when evaluating the efficacy of IABP for CS.

Prevalence of Noncardiac Multimorbidity in Patients Admitted to Two Cardiac Intensive Care Units and Their Association with Mortality

BACKGROUND

Current cardiac intensive care unit (CICU) practice has seen an increase in patient complexity, including an increase in noncardiac organ failure, critical care therapies, and comorbidities. We sought to describe the changing epidemiology of noncardiac multimorbidity in the CICU population.

METHODS

We analyzed consecutive unique patient admissions to 2 geographically distant tertiary care CICUs (n = 16,390). We assessed for the prevalence of 0, 1, 2, and ≥3 noncardiac comorbidities (diabetes, chronic lung, liver, and kidney disease, cancer, and stroke/transient ischemic attack) and their associations with hospital and postdischarge 1-year mortality using multivariable logistic regression.

RESULTS

The prevalence of 0, 1, 2, and ≥3 noncardiac comorbidities was 37.7%, 31.4%, 19.9%, and 11.0%, respectively. Increasing noncardiac comorbidities were associated with a stepwise increase in mortality, length of stay, noncardiac indications for ICU admission, and increased utilization of critical care therapies. After multivariable adjustment, compared with those without noncardiac comorbidities, there was an increased hospital mortality for patients with 1 (odds ratio [OR] 1.30; 95% confidence interval [CI], 1.10-1.54, P = .002), 2 (OR 1.47; 95% CI, 1.22-1.77, P < .001), and ≥3 (OR 1.79; 95% CI, 1.44-2.22, P < .001) noncardiac comorbidities. Similar trends for each additional noncardiac comorbidity were seen for postdischarge 1-year mortality (P < .001, all).

CONCLUSIONS

In 2 large contemporary CICU populations, we found that noncardiac multimorbidity was highly prevalent and a strong predictor of short- and long-term adverse clinical outcomes. Further study is needed to define the best care pathways for CICU patients with acute cardiac illness complicated by noncardiac multimorbidity.