Cardiogenic Shock Due to End-Stage Heart Failure and Acute Myocardial Infarction: Characteristics and Outcome of Temporary Mechanical Circulatory Support

Management of cardiogenic shock: state-of-the-art

The management of cardiogenic shock is an ongoing challenge. Despite all efforts and tremendous use of resources, mortality remains high. Whilst reversing the underlying cause, restoring/maintaining organ perfusion and function are cornerstones of management. The presence of comorbidities and preexisting organ dysfunction increases management complexity, aiming to integrate the needs of vital organs in each individual patient. This review provides a comprehensive overview of contemporary literature regarding the definition and classification of cardiogenic shock, its pathophysiology, diagnosis, laboratory evaluation, and monitoring. Further, we distill the latest evidence in pharmacologic therapy and the use of mechanical circulatory support including recently published randomized-controlled trials as well as future directions of research, integrating this within an international group of authors to provide a global perspective. Finally, we explore the need for individualization, especially in the face of neutral randomized trials which may be related to a dilution of a potential benefit of an intervention (i.e., average effect) in this heterogeneous clinical syndrome, including the use of novel biomarkers, artificial intelligence, and machine learning approaches to identify specific endotypes of cardiogenic shock (i.e., subclasses with distinct underlying biological/molecular mechanisms) to support a more personalized medicine beyond the syndromic approach of cardiogenic shock.

Hemodynamic management of cardiogenic shock in the intensive care unit

Hemodynamic derangements are defining features of cardiogenic shock. Randomized clinical trials have examined the efficacy of various therapeutic interventions, from percutaneous coronary intervention to inotropes and mechanical circulatory support (MCS). However, hemodynamic management in cardiogenic shock has not been well-studied. This State-of-the-Art review will provide a framework for hemodynamic management in cardiogenic shock, including a description of the 4 therapeutic phases from initial 'Rescue' to 'Optimization', 'Stabilization' and 'de-Escalation or Exit therapy' (R-O-S-E), phenotyping and phenotype-guided tailoring of pharmacological and MCS support, to achieve hemodynamic and therapeutic goals. Finally, the premises that form the basis for clinical management and the hypotheses for randomized controlled trials will be discussed, with a view to the future direction of cardiogenic shock.

Inotropic Agents: Are We Still in the Middle of Nowhere?

Inotropes are prescribed to enhance myocardial contractility while vasopressors serve to improve vascular tone. Although these medications remain a life-saving therapy in cardiovascular clinical scenarios with hemodynamic impairment, the paucity of evidence on these drugs makes the choice of the most appropriate vasoactive agent challenging. As such, deep knowledge of their pharmacological and hemodynamic effects becomes crucial to optimizing hemodynamic profile while reducing the potential adverse effects. Given this perspective, it is imperative for cardiologists to possess a comprehensive understanding of the underlying mechanisms governing these agents and to discern optimal strategies for their application across diverse clinical contexts. Thus, we briefly review these agents' pharmacological and hemodynamic properties and their reasonable clinical applications in cardiovascular settings. Critical interpretation of available data and the opportunities for future investigations are also highlighted.

Impact of Age, Gender, and Body Mass Index on Short-Term Outcomes of Patients With Cardiogenic Shock on Mechanical Circulatory Support

This single-center, observational study assessed the impact of age, gender, and body mass index (BMI) in patients with cardiogenic shock (CS) on temporary mechanical circulatory support. All adult patients admitted to the Cleveland Clinic main campus Cardiac Intensive Care Unit (CICU) between December 1, 2015, to December 31, 2019, CICU with CS necessitating mechanical circulatory support (MCS) with intra-aortic balloon pump, Impella, or venous arterial-extra corporeal membrane oxygenation were retrospectively analyzed for this study. Baseline characteristics and 30-day outcomes were collected through physician-directed chart review. The impact of age, gender, and BMI on 30-day mortality was assessed using multivariable logistic regression. Kaplan-Meier survival curves were used to analyze the survival difference in specific subsets. A total of 393 patients with CS on temporary MCS were admitted to our CICU during the study period. The median age of our cohort was 63 years (interquartile range 54 to 70 years), median BMI was 28.50 kg/m2 (interquartile range 24.62 to 29.72) and 70% (n = 276) were men. In total, 22 patients >80 years had received MCS compared with 372 patients <80 years. Patients >80 years on MCS had significantly higher 30-day mortality compared with those <80 years (81.8% vs 49.3%, p = 0.006). Upon stratifying patients by BMI, 161 (41%) patients were found to have BMI ≥30 kg/m2 whereas 232 (59%) patients had BMI <30 kg/m2. Comparison of 30-day mortality revealed that patients with BMI ≥30 did significantly worse than patients with BMI <30 (59.6% vs 45.3%, p = 0.007). There was no difference in 30-day mortality between men and women. On multivariable logistic regression, both age and BMI had a positive linear relation with adjusted 30-day mortality whereas gender did not have a major effect. Advanced age and higher BMI are independently associated with worse outcomes in patients with CS on MCS. Utilizing a strict selection criterion for patients in CS is pertinent to derive the maximum benefit from advanced mechanical support.

Pulmonary Artery Catheter Usage and Impact on Mortality in Patients With Cardiogenic Shock: Results From a Canadian Single-Centre Registry

BACKGROUND

Hemodynamic assessment for cardiogenic shock (CS) phenotyping in patients has led to renewed interest in the use of pulmonary artery catheters (PACs).

METHODS

We included patients admitted with CS from January 2014 to December 2020 and compared clinical outcomes among patients who received PACs and those who did not. The primary outcome was the rate of in-hospital mortality. Secondary outcomes included use of advanced heart failure therapies and coronary intensive care unit (CICU) and hospital lengths of stay.

RESULTS

A total of 1043 patients were analysed and 47% received PACs. Patients selected for PAC-guided management were younger and had lower left ventricular function. They also had higher use of vasopressor and inotropes, and 15.2% of them were already supported with temporary mechanical circulatory support (MCS). In-hospital mortality was lower in patients who received PACs (29.3% vs 36.2%; P = 0.02), mainly driven by a reduction in mortality among those in Society for Cardiovascular Angiography and Interventions (SCAI) stages D and E CS. Patients who received PACs were more likely to receive temporary MCS with Impella, durable ventricular assist devices (VADs), or orthotopic heart transplantation (OHT) (P < 0.001 for all analyses). CICU and hospital lengths of stay were longer in patients who used PACs.

CONCLUSIONS

Among patients with CS, the use of PACs was associated with lower in-hospital mortality, especially among those in SCAI stages D and E. Patients who received PACs were also more frequently rescued with temporary MCS or received advanced heart failure therapies, such as durable VADs or OHT.

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.

Differential effect of left ventricular unloading according to the aetiology of cardiogenic shock

AIMS

Evidence for the effectiveness of left ventricular (LV) unloading in patients who received venoaterial extracorporeal membrane oxygenation (VA-ECMO) for acute myocardial infarction (AMI) or non-AMI induced cardiogenic shock (CS) is limited. The aim of the present study was to compare the effect of LV unloading in AMI-induced and non-AMI-induced CS.

METHODS AND RESULTS

This is a single-centre retrospective observational study of patients with CS undergoing VA-ECMO from January 2011 to March 2019. Patients were classified as AMI-induced and non-AMI-induced CS. The association of LV unloading with 90-day mortality in both groups was analysed using Cox proportional hazard regression analysis.

RESULTS

Of the 128 CS patients, 71 (55.5%) patients received VA-ECMO due to AMI-induced CS, and the remaining 57 (44.5%) received VA-ECMO due to non-AMI-induced CS. The modality of LV unloading was predominantly with IABP (94.5%). In the AMI-induced CS group, LV unloading did not reduce 90-day mortality (adjusted hazard ratio 1.96, 95% confidence interval 0.90-4.27, P = 0.089). However, in the non-AMI-induced CS group, LV unloading combined with VA-ECMO significantly reduced 90-day mortality (adjusted hazard ratio 0.37, 95% confidence interval 0.14-0.96, P = 0.041; P for interaction = 0.029) as compared with those who received VA-ECMO alone.

CONCLUSIONS

LV unloading with VA-ECMO may reduce 90-day mortality compared with VA-ECMO alone in patients with non-AMI-induced CS, but not in AMI-induced CS.

National Trends for Temporary Mechanical Circulatory Support Utilization in Patients With Cardiogenic Shock From Decompensated Chronic Heart Failure: Incidence, Predictors, Outcomes, and Cost

Background

Trends in temporary mechanical circulatory support (tMCS) use with associated outcomes and cost in cardiogenic shock secondary to decompensated chronic heart failure (HF-CS) remains poorly understood. We describe trends in tMCS use, associated outcomes, and cost in HF-CS.

Methods

We included adults enrolled in a national insurance claims dataset with HF-CS who received intra-aortic balloon pump (IABP), Impella, or extracorporeal membrane oxygenation (ECMO) without acute coronary syndrome, or postcardiotomy shock. We identified predictors of device use, associated outcomes, and inflation-adjusted costs.

Results

We studied 2722 HF-CS patients receiving tMCS: 1799 (66%) male, 1771 (65%) White, and 1836 (67%) with ischemic cardiomyopathy. Rate of tMCS use increased from 2010-2019. Impella use showed the largest increase (Δ+344%), followed by ECMO (Δ+112%). Patients receiving ECMO had a higher comorbidity burden, and patients receiving IABP were more likely to have valvular heart disease. Compared with IABP, 30-day mortality rate was no different for Impella (adjusted odds ratio, 1.24; 95% CI, 0.93-1.66) but was higher with ECMO (adjusted odds ratio, 3.08; 95% CI, 2.22-4.27). Adjusted hospitalization cost was highest for ECMO (median, $191,079 [IQR, $165,760-$239,373]), followed by Impella (median, $142,518 [IQR, $126,845-$179,938]), and IABP (median, $132,060 [IQR, $113,794-$160,244]). We observed a linear association between price standardized cost-quartile and complications, but not for 30-day mortality.

Conclusions

The use of Impella and ECMO is increasing with an associated cost increase. The use of ECMO coincided with higher 30-day mortality compared with IABP in HF-CS. These findings likely reflect increasing disease severity and evolving practice patterns rather than causation.

Acute mechanical circulatory support for cardiogenic shock in India

Cardiogenic shock continues to have high morbidity and mortality, despite advances in the field. Temporary mechanical circulatory support (TMCS) devices, if instituted in a timely fashion, can help stabilize critically ill patients with cardiogenic shock from various aetiologies and cardiac arrest, and provide time for organ recovery or till durable support or transplantation can be achieved. Currently, several options for TMCS devices exist. In this review, we discuss indications, contraindications, characteristics of the various available devices, and important issues pertaining to their management.

Update on cardiogenic shock: from detection to team management

PURPOSE OF REVIEW

The following review is intended to provide a summary of contemporary cardiogenic shock (CS) profiling and diagnostic strategies, including biomarker and hemodynamic-based (invasive and noninvasive) monitoring, discuss clinical differences in presentation and trajectory between acute myocardial infarction (AMI)-CS and heart failure (HF)-CS, describe transitions to native heart recovery and heart replacement therapies with a focus on tailored management and emerging real-world data, and emphasize trends in team-based initiatives and interventions for cardiogenic shock including the integration of protocol-driven care.

RECENT FINDINGS

This document provides a broad overview of contemporary scientific consensus statements as well as data derived from randomized controlled clinical trials and observational registry working groups focused on cardiogenic shock management.

SUMMARY

This review highlights the increasingly important role of pulmonary artery catheterization in AMI-CS and HF-CS cardiogenic shock and advocates for routine application of algorithmic approaches with interdisciplinary care pathways. Cardiogenic shock algorithms facilitate the integration of clinical, hemodynamic, and imaging data to determine the most appropriate patient hemodynamic support platform to achieve adequate organ perfusion and decongestion.

Outcomes, Temporal Trends, and Resource Utilization in Ischemic versus Nonischemic Cardiogenic Shock

Cardiogenic shock (CS) is associated with significant morbidity and mortality. Differentiating the etiologic factors driving CS has epidemiological significance and aids in optimization of therapeutic strategies, prognostication, and resource utilization. The aim herein is to investigate the epidemiology and clinical outcomes of CS in those with ischemic and nonischemic CS etiologies. Using International Classification of Diseases codes, we queried the national inpatient sample for CS hospitalization from 2007 to 2018 and divided the study sample into cohorts of ischemic (I-CS) and nonischemic cardiogenic shock (NI-CS). We then compared the primary outcome of in-hospital mortality between these 2 cohorts. Two groups of secondary outcomes (clinical and procedural) were also assessed between the 2 cohorts. CS was present in 557,860 hospitalizations; 84% of these were I-CS and 15.8% NI-CS. Patients with I-CS were older, more commonly males, with more risk factors for coronary artery disease (P < 0.05). NI-CS had higher prevalence of preexisting systolic heart failure and atrial fibrillation. The in-hospital mortality was significantly higher in patients with I-CS (32.2% vs. 29.5%, adjusted odds ratio 1.10, P < 0.001). Frequencies of acute ischemic stroke, mechanical ventilation, ventricular arrhythmias, and vascular complications were higher in I-CS versus NI-CS, while acute kidney injury and acute liver failure were more common in NI-CS (P < 0.05). The use of mechanical circulatory support devices was higher in the I-CS group. In conclusion, patients with I-CS comprise the vast majority of CS and are associated with higher mortality and higher resource utilization. Conversely, patients with NI-CS appear to have higher survival but with a higher prevalence of end-organ dysfunction.

Pulmonary artery catheterization in acute myocardial infarction complicated by cardiogenic shock: A review of contemporary literature

Acute myocardial infarction (AMI) with left ventricular (LV) dysfunction patients, the most common cause of cardiogenic shock (CS), have acutely deteriorating hemodynamic status. The frequent use of vasopressor and inotropic pharmacologic interventions along with mechanical circulatory support (MCS) in these patients necessitates invasive hemodynamic monitoring. After the pivotal Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness trial failed to show a significant improvement in clinical outcomes in shock patients managed with a pulmonary artery catheter (PAC), the use of PAC has become less popular in clinical practice. In this review, we summarize currently available literature to summarize the indications, clinical relevance, and recommendations for use of PAC in the setting of AMI-CS.

Intra-Aortic Balloon Pumping in Acute Decompensated Heart Failure With Hypoperfusion: From Pathophysiology to Clinical Practice

Trials on intra-aortic balloon pump (IABP) use in cardiogenic shock related to acute myocardial infarction have shown disappointing results. The role of IABP in cardiogenic shock treatment remains unclear, and new (potentially more potent) mechanical circulatory supports with arguably larger device profile are emerging. A reappraisal of the physiological premises of intra-aortic counterpulsation may underpin the rationale to maintain IABP as a valuable therapeutic option for patients with acute decompensated heart failure and tissue hypoperfusion. Several pathophysiological features differ between myocardial infarction- and acute decompensated heart failure-related hypoperfusion, encompassing cardiogenic shock severity, filling status, systemic vascular resistances rise, and adaptation to chronic (if preexisting) left ventricular dysfunction. IABP combines a more substantial effect on left ventricular afterload with a modest increase in cardiac output and would therefore be most suitable in clinical scenarios characterized by a disproportionate increase in afterload without profound hemodynamic compromise. The acute decompensated heart failure syndrome is characterized by exquisite afterload-sensitivity of cardiac output and may be an ideal setting for counterpulsation. Several hemodynamic variables have been shown to predict response to IABP within this scenario, potentially guiding appropriate patient selection. Finally, acute decompensated heart failure with hypoperfusion may frequently represent an end stage in the heart failure history: IABP may provide sufficient hemodynamic support and prompt end-organ function recovery in view of more definitive heart replacement therapies while preserving ambulation when used with a transaxillary approach.

De Novo vs Acute-on-Chronic Presentations of Heart Failure-Related Cardiogenic Shock: Insights from the Critical Care Cardiology Trials Network Registry

BACKGROUND

Heart failure-related cardiogenic shock (HF-CS) accounts for an increasing proportion of cases of CS in contemporary cardiac intensive care units. Whether the chronicity of HF identifies distinct clinical profiles of HF-CS is unknown.

METHODS AND RESULTS

We evaluated admissions to cardiac intensive care units for HF-CS in 28 centers using data from the Critical Care Cardiology Trials Network registry (2017-2020). HF-CS was defined as CS due to ventricular failure in the absence of acute myocardial infarction and was classified as de novo vs acute-on-chronic based on the absence or presence of a prior diagnosis of HF, respectively. Clinical features, resource use, and outcomes were compared among groups. Of 1405 admissions with HF-CS, 370 had de novo HF-CS (26.3%), and 1035 had acute-on-chronic HF-CS (73.7%). Patients with de novo HF-CS had a lower prevalence of hypertension, diabetes, coronary artery disease, atrial fibrillation, and chronic kidney disease (all P < 0.01). Median Sequential Organ Failure Assessment (SOFA) scores were higher in those with de novo HF-CS (8; 25th-75th: 5-11) vs acute-on-chronic HF-CS (6; 25th-75th: 4-9, P < 0.01), as was the proportion of Society of Cardiovascular Angiography and Intervention (SCAI) shock stage E (46.1% vs 26.1%, P < 0.01). After adjustment for clinical covariates and preceding cardiac arrest, the risk of in-hospital mortality was higher in patients with de novo HF-CS than in those with acute-on-chronic HF-CS (adjusted hazard ratio 1.36, 95% confidence interval 1.05-1.75, P = 0.02).

CONCLUSIONS

Despite having fewer comorbidities, patients with de novo HF-CS had more severe shock presentations and worse in-hospital outcomes. Whether HF disease chronicity is associated with time-dependent compensatory adaptations, unique pathobiological features and responses to treatment in patients presenting with HF-CS warrants further investigation.

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.

Outcome of patients with non-ischaemic cardiogenic shock supported by percutaneous left ventricular assist device

Aims

Percutaneous left ventricular assist devices (pVADs) are used to haemodynamically stabilize patients with cardiogenic shock (CS) caused by acute myocardial infarction (AMI). One out of every two patients has a non‐ischaemic cause of CS, and these patients differ profoundly from patients with AMI‐related CS. We assessed the usefulness of pVAD support for patients with non‐ischaemic CS.

Methods and results

We analysed 106 patients with CS and Impella® support between 2015 and 2018. CS was non‐ischaemic in 36 patients and AMI‐related in 70 patients. Compared with the AMI group, those in the non‐ischaemic group were significantly younger [median age 62 (50.8, 70.8) years vs. 68 (58.0, 75.5) years, P = 0.007] and had more patients with severely reduced left ventricular function (94% vs. 79%, P = 0.035) and worse glomerular filtration rate [45 (27, 57) mL/min vs. 60 (44, 78) mL/min]. Propensity score matching yielded 31 patients with non‐ischaemic CS and 31 patients with AMI‐related CS, without a difference in baseline laboratory values or comorbidities. In both groups, pVAD support was performed along with haemodynamic stabilization, reduction of catecholamines and normalization of lactate levels. In 7 days, systolic blood pressure increased from 91 (80, 101) mmHg at baseline to 100 (100, 120) mmHg in the non‐ischaemic CS group (P = 0.001) and 89 (80, 100) mmHg at baseline to 112 (100, 128) mmHg in the AMI‐related CS group (P = 0.001). Moreover, in 7 days, the need of catecholamines (calculated as vasoactive‐inotropic score) decreased from 32.0 (11.1, 47.0) at baseline to 5.3 (0, 16.1) in the non‐ischaemic group (P = 0.001) and from 35.2 (18.11, 67.0) to zero (0, 0) in the AMI‐related CS group (P = 0.001). Lactate level decreased from 3.8 (2.8, 5.9) mmol/L at baseline to 1.0 (0.8, 2.1) mmol/L (P = 0.001) in the non‐ischaemic CS group and from 3.8 (2.6, 6.5) mmol/L to 1.2 (1.0, 2.0) mmol/L in the AMI‐related group (P = 0.001).

In the non‐ischaemic CS group, eight patients (25.8%) were upgraded to veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) or long‐term mechanical circulatory support. Two of these upgraded patients received heart transplantation. In the AMI group, eight patients (25.8%) were upgraded to VA‐ECMO or long‐term mechanical circulatory support. Ninety‐day survival did not significantly differ between the groups (non‐ischaemic CS group 48.4%, AMI‐related CS group 45.2%, P = 0.799).

Conclusions

pVAD support is useful for haemodynamic stabilization of patients with non‐ischaemic CS and is valuable as a bridge to patients' recovery or long‐term left ventricular support and heart transplantation.

Association of Lymphocyte to Monocyte Ratio and Risk of in-Hospital Mortality in Patients with Cardiogenic Shock: A Propensity Score Matching Study

Background

Lymphocyte to monocyte ratio (LMR) has been long implicated in the prediction of many inflammatory-related diseases. However, the possible value as prognostic marker of LMR have not been evaluated in cardiogenic shock (CS) patients. The aim of the study was to assess the relationship between LMR on admission and in-hospital mortality in CS patients.

Methods

Data on patients diagnosed with CS were extracted from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database. We performed a single-institution, retrospective study of 1487 CS patients and determined the optimal cut-off for LMR by X-tile software. Propensity score matching (PSM) and inverse probabilities of treatment weighting (IPTW) were conducted to control confounders. Cox proportional hazards model was performed to evaluate the relationship between LMR and in-hospital mortality. Kaplan-Meier curves and receiver operating characteristics (ROC) analysis were applied to assess the prognostic value of LMR.

Results

The optimal cut-off value for LMR was 0.9. Cox proportional hazards model demonstrated that lower LMR (< 0.9) was independently associated with in-hospital mortality with hazard ratio (HR) of 1.40 (1.12-1.74, P = 0.003). The results were consistent with survival analyses (P < 0.001, Log rank test). Adding LMR< 0.9 to the sequential organ failure assessment (SOFA) score improved discrimination and risk stratification for in-hospital mortality.

Conclusion

Lower level of LMR is related to higher risk of in-hospital mortality of patients with CS. As an easily available biomarker, LMR can independently predict the in-hospital mortality in CS patients.

Obesity and Outcomes Following Cardiogenic Shock Requiring Acute Mechanical Circulatory Support

BACKGROUND

The association of obesity on outcomes in patients with cardiogenic shock requiring acute mechanical circulatory support has not been thoroughly investigated.

METHODS

We evaluated the National Readmission Database for adults with either acute myocardial infarction or heart failure complicated by cardiogenic shock requiring acute mechanical circulatory support between January 2016 and November 2017. Exposure was assessed using International Classification of Diseases, Tenth Revision codes for the degree of obesity with the reference being body mass index (BMI) of 20.0 to 29.9 group. Multiple logistic regression and Cox regression analysis were used to analyze in-hospital mortality and 30-day readmission, respectively.

RESULTS

The survey-weighted sample included a total of 35 555 hospitalizations with a mean age of 65.4±0.2 years and 29.8% females. Obesity was associated with higher in-hospital mortality (no obesity, 26.4% [BMI, 20.0-29.9] versus class I obesity, 25.0% [BMI, 30.0-34.9] versus class II obesity, 28.7% [BMI, 35.0-39.9] versus class III obesity, 34.9% [BMI, ≥40]; P<0.001). On stratified analysis, compared with a nonobese phenotype, younger adults (age <60) with class II and class III obesity (odds ratio, 1.9 [95% CI, 1.1-3.5], P=0.02; odds ratio, 2.1 [95% CI, 1.2-3.7], P=0.01) and older adults (age ≥60) with class III obesity (odds ratio, 1.7 [95% CI, 1.2-2.4], P=0.005) had higher mortality. There was no association between the degree of obesity and 30-day readmission.

CONCLUSIONS

Among adults with acute myocardial infarction or acute heart failure resulting in cardiogenic shock requiring acute mechanical circulatory support, younger adults with class II and class III obesity and older patients with class III obesity have a higher risk of in-hospital mortality compared with nonobese patients.

Outcomes of temporary mechanical circulatory support in cardiogenic shock due to end-stage heart failure

Background

There are few reports of mechanical circulatory support (MCS) in patients with cardiogenic shock (CS) due to end-stage heart failure (ESHF). We evaluated our institutional MCS strategy and compared the outcomes of INTERMACS 1 and 2 patients with CS due to ESHF.

Methods

Retrospective analysis of prospectively collected data (November 2014 to July 2019) from a single centre. ESHF was defined by a diagnosis of HF prior to presentation with CS. Other causes of CS (eg: acute myocardial infarction) were excluded. We compared the clinical course, complications and 90-day survival of patients with CS due to ESHF in INTERMACS profile 1 and 2.

Results

We included 60 consecutive patients with CS due to ESHF Differences in baseline characteristics were consistent with the INTERMACS profiles. The duration of MCS was similar between INTERMACS 1 and 2 patients (14 (10–33) vs 15 (7–23) days, p = 0.439). There was no significant difference in the number of patients with complications that required intervention. Compared to INTERMACS 2, INTERMACS 1 patients had more organ dysfunction on support and significant lower 90-day survival (66% vs 34%, p = 0.016).

Conclusion

Our temporary MCS strategy, including earlier intervention in patients with CS due to ESHF at INTERMACS 2 was associated with less organ dysfunction and better 90-day survival compared to INTERMACS 1 patients.

The Physiologic Basis and Clinical Outcomes of Combined Impella and Veno-Arterial Extracorporeal Membrane Oxygenation Support in Cardiogenic Shock

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) provides effective hemodynamic support in cardiogenic shock, but in some cases may be complicated by left ventricular (LV) distension and pulmonary edema. The Impella, a catheter-mounted microaxial pump has been used to unload the LV. Recent studies have compared the clinical outcomes of VA-ECMO to the combination of Impella and VA-ECMO. The purpose of this review is threefold: firstly, to discuss the physiological effects of Impella support in addition to VA-ECMO, secondly to review published studies on the outcome of this combined support, and thirdly to provide a practical overview of the approach to combining Impella and VA-ECMO.

Outcomes of Hospitalizations for Cardiogenic Shock at Left Ventricular Assist Device Versus Non-Left Ventricular Assist Device Centers

Background Cardiogenic shock (CS) is a complex syndrome associated with high morbidity and mortality. In recent years, many US hospitals have formed multidisciplinary shock teams capable of rapid diagnosis and triage. Because of preexisting collaborative systems of care, hospitals with left ventricular assist device (LVAD) programs may also represent "centers of excellence" for CS care. However, the outcomes of patients with CS at LVAD centers have not been previously evaluated. Methods and Results Patients with CS were identified in the 2012 to 2014 National Inpatient Sample. Clinical characteristics, revascularization rates, and use of mechanical circulatory support were analyzed in LVAD versus non-LVAD centers. The association between hospital type and in-hospital mortality was examined using multivariable logistic regression models. Of 272 075 hospitalizations, 26.0% were in LVAD centers. CS attributable to causes other than acute myocardial infarction represented most cases. In-hospital mortality was lower in LVAD centers (38.9% versus 43.3%; P<0.001). In multivariable analysis, the odds of mortality remained significantly lower for hospitalizations in LVAD centers (odds ratio, 0.89; P<0.001). In patients with CS secondary to acute myocardial infarction, revascularization rates were similar between LVAD and non-LVAD centers. The use of intra-aortic balloon pump (18.7% versus 18.8%) and Impella/TandemHeart (2.6% versus 1.9%) was similar between hospital types, whereas extracorporeal membrane oxygenation was used more frequently in LVAD centers (4.3% versus 0.2%; P<0.001). Conclusions Risk-adjusted mortality was lower in patients with CS who were hospitalized at LVAD centers. These centers likely represent specialized, shock team capable institutions across the country that may be best suited to manage patients with CS.

A Standardized and Comprehensive Approach to the Management of Cardiogenic Shock

Cardiogenic shock is a hemodynamically complex syndrome characterized by a low cardiac output that often culminates in multiorgan system failure and death. Despite recent advances, clinical outcomes remain poor, with mortality rates exceeding 40%. In the absence of adequately powered randomized controlled trials to guide therapy, best practices for shock management remain nonuniform. Emerging data from North American registries, however, support the use of standardized protocols focused on rapid diagnosis, early intervention, ongoing hemodynamic assessment, and multidisciplinary longitudinal care. In this review, the authors examine the pathophysiology and phenotypes of cardiogenic shock, benefits and limitations of current therapies, and they propose a standardized and team-based treatment algorithm. Lastly, they discuss future research opportunities to address current gaps in clinical knowledge.

Noninvasive Hemodynamic Assessment of Shock Severity and Mortality Risk Prediction in the Cardiac Intensive Care Unit

OBJECTIVES

This study sought to define the 2-dimensional and Doppler echocardiographic hemodynamics associated with each Society for Cardiovascular Angiography and Interventions (SCAI) stage, and to determine their association with mortality.

BACKGROUND

The SCAI shock stages classification stratifies mortality risk in cardiac intensive care unit (CICU) patients, but the echocardiographic and hemodynamic parameters that define these SCAI shock stages are unknown.

METHODS

Unique CICU patients admitted from 2007 to 2015 who had a transthoracic echocardiogram within 1 day of CICU admission were included. Echocardiographic variables were evaluated as a function of SCAI shock stage. Multivariable logistic regression determined the association between echocardiographic parameters with adjusted hospital mortality.

RESULTS

We included 5,453 patients with a median age of 69.3 years (interquartile range: 58.2 to 79.0 years) (37% women), and a median left ventricular ejection fraction (LVEF) of 50% (interquartile range: 35% to 61%). Higher SCAI shock stages were associated with lower LVEF and worse systemic hemodynamics. Hospital mortality was higher in patients with LVEF <40%, cardiac index <1.8 l/min/m², stroke volume index <35 ml/m², cardiac power output <0.6 W, or medial early mitral valve inflow velocity to early diastolic annular velocity (E/e') ratio >15 (particularly in SCAI shock Stages A to C). After multivariable adjustment, only stroke volume index <35 ml/m² (adjusted odds ratio: 2.0; 95% confidence interval: 1.4 to 3.0; p < 0.001) and E/e' ratio >15 (adjusted odds ratio: 1.52; 95% confidence interval: 1.04 to 2.23; p = 0.03) remained associated with higher hospital mortality.

CONCLUSIONS

Noninvasive 2-dimensional and Doppler echocardiographic parameters correlate with the SCAI shock stages and improve risk stratification for hospital mortality in CICU patients. Low stroke volume index and high E/e' ratio demonstrated the strongest association with hospital mortality.

Pulmonary artery catheter use in acute myocardial infarction-cardiogenic shock

Aims

The aim of this study is to evaluate the contemporary use of a pulmonary artery catheter (PAC) in acute myocardial infarction‐cardiogenic shock (AMI‐CS).

Methods and results

A retrospective cohort of AMI‐CS admissions using the National Inpatient Sample (2000–2014) was identified. Admissions with concomitant cardiac surgery or non‐AMI aetiology for cardiogenic shock were excluded. The outcomes of interest were in‐hospital mortality, resource utilization, and temporal trends in cohorts with and without PAC use. In the non‐PAC cohort, the use and outcomes of right heart catheterization was evaluated. Multivariable regression and propensity matching was used to adjust for confounding. During 2000–2014, 364 001 admissions with AMI‐CS were included. PAC was used in 8.1% with a 75% decrease during over the study period (13.9% to 5.4%). Greater proportion of admissions to urban teaching hospitals received PACs (9.5%) compared with urban non‐teaching (7.1%) and rural hospitals (5.4%); P < 0.001. Younger age, male sex, white race, higher comorbidity, noncardiac organ failure, use of mechanical circulatory support, and noncardiac support were independent predictors of PAC use. The PAC cohort had higher in‐hospital mortality (adjusted odds ratio 1.07 [95% confidence interval 1.04–1.10]), longer length of stay (10.9 ± 10.9 vs. 8.2 ± 9.3 days), higher hospitalization costs ($128 247 ± 138 181 vs. $96 509 ± 116 060), and lesser discharges to home (36.3% vs. 46.4%) (all P < 0.001). In 6200 propensity‐matched pairs, in‐hospital mortality was comparable between the two cohorts (odds ratio 1.01 [95% confidence interval 0.94–1.08]). Right heart catheterization was used in 12.5% of non‐PAC admissions and was a marker of greater severity but did not indicate worse outcomes.

Conclusions

In AMI‐CS, there was a 75% decrease in PAC use between 2000 and 2014. Admissions receiving a PAC were a higher risk cohort with worse clinical outcomes.

Outcome differences in acute vs. acute on chronic heart failure and cardiogenic shock

Aims

Despite advances in coronary reperfusion and percutaneous mechanical circulatory support, mortality among patients presenting with cardiogenic shock (CS) remains unacceptably high. Clinical trials and risk stratification tools have largely focused on acute CS, particularly secondary to acute coronary syndrome. Considerably less is understood about CS in the setting of acute decompensation in patients with chronic heart failure (HF). We sought to compare outcomes between patients with acute CS and patients with acute on chronic decompensated HF presenting with laboratory and haemodynamic features consistent with CS.

Methods and results

Sequential patients admitted with CS at a single quaternary centre between January 2014 and August 2017 were identified. Acute on chronic CS was defined by having a prior diagnosis of HF. Initial haemodynamic and laboratory data were collected for analysis. The primary outcome was in‐hospital mortality. Secondary outcomes were use of temporary mechanical circulatory support, durable ventricular assist device implantation, total artificial heart implantation, or heart transplantation. Comparison of continuous variables was performed using Student's t‐test. For categorical variables, the χ² statistic was used. A total of 235 patients were identified: 51 patients (32.8%) had acute CS, and 184 patients (64.3%) had acute decompensation of chronic HF with no differences in age (52 ± 22 vs. 55 ± 14 years, P = 0.28) or gender (26% vs. 23%, P = 0.75) between the two groups. Patients with acute CS were more likely to suffer in‐hospital death (31.4% vs. 9.8%, P < 0.01) despite higher usage of temporary mechanical circulatory support (52% vs. 25%, P < 0.01) compared with patients presenting with acute on chronic HF. The only clinically significant haemodynamic differences at admission were a higher heart rate (101 ± 29 vs. 82 ± 17 b.p.m., P < 0.01) and wider pulse pressure (34 ± 19 vs. 29 ± 10 mmHg, P < 0.01) in the acute CS group. There were no significant differences in degree of shock based on commonly used CS parameters including mean arterial pressure (72 ± 12 vs. 74 ± 10 mmHg, P = 0.23), cardiac output (3.9 ± 1.2 vs. 3.8 ± 1.2 L/min, P = 0.70), or cardiac power index (0.32 ± 0.09 vs. 0.30 ± 0.09 W/m², P = 0.24) between the two groups.

Conclusions

Current definitions and risk stratification models for CS based on clinical trials performed in the setting of acute coronary syndrome may not accurately reflect CS in patients with acute on chronic HF. Further investigation into CS in patients with acute on chronic HF is warranted.

Mechanical circulatory support in cardiogenic shock

PURPOSE OF REVIEW

Cardiogenic shock remains a complex clinical syndrome with high morbidity and mortality. The purpose of this article is to review important landmark trials as well as the relevant recent literature for percutaneous mechanical circulatory support following acute myocardial infarction.

RECENT FINDINGS

The sole use of intraaortic balloon pumps for cardiogenic shock following acute myocardial infarction continues to be questioned with downgrading of its recommendation in recent years, there however may remain a role in patients with mechanical complications of their myocardial infarction. The combined use of extracorporeal circulatory support and a ventricular unloading device appears to be promising with increasing data supporting this strategy.

SUMMARY

Given the complex and heterogeneous nature of cardiogenic shock there remains somewhat limited robust data to guide clinical practice. Ongoing research is needed to help guide improvements in patient outcomes.

Temporal trends, predictors, and outcomes of acute kidney injury and hemodialysis use in acute myocardial infarction-related cardiogenic shock

Background

There are limited data on acute kidney injury (AKI) complicating acute myocardial infarction with cardiogenic shock (AMI-CS). This study sought to evaluate 15-year national prevalence, temporal trends and outcomes of AKI with no need for hemodialysis (AKI-ND) and requiring hemodialysis (AKI-D) following AMI-CS.

Methods

This was a retrospective cohort study from 2000–2014 from the National Inpatient Sample (20% stratified sample of all community hospitals in the United States). Adult patients (>18 years) admitted with a primary diagnosis of AMI and secondary diagnosis of CS were included. The primary outcome was in-hospital mortality in cohorts with no AKI, AKI-ND, and AKI-D. Secondary outcomes included predictors, resource utilization and disposition.

Results

During this 15-year period, 440,257 admissions for AMI-CS were included, with AKI in 155,610 (35.3%) and hemodialysis use in 14,950 (3.4%). Older age, black race, non-private insurance, higher comorbidity, organ failure, and use of cardiac and non-cardiac organ support were associated with the AKI development and hemodialysis use. There was a 2.6-fold higher adjusted risk of developing AKI in 2014 compared to 2000. Presence of AKI-ND and AKI-D was associated with a 1.3 and 1.7-fold higher adjusted risk of mortality. Compared to the cohort without AKI, AKI-ND and AKI-D were associated with longer length of stay (9±10, 12±13, and 18±19 days respectively; p<0.001) and higher hospitalization costs ($101,859±116,204, $159,804±190,766, and $265,875 ± 254,919 respectively; p<0.001).

Conclusion

AKI-ND and AKI-D are associated with higher in-hospital mortality and resource utilization in AMI-CS.

Metabolic Acidosis in Critically Ill Cirrhotic Patients with Acute Kidney Injury

Background and Aims: The metabolic acid-base disorders have a high incidence of acute kidney injury (AKI) in critically ill cirrhotic patients (CICPs). The aims of our study were to ascertain the composition of metabolic acidosis of CICPs with AKI and explore its relationship with hospital mortality. Methods: Three-hundred and eighty consecutive CICPs with AKI were eligible for the cohort study. Demographic, clinical and laboratory parameters were recorded and arterial acid-base state was analyzed by the Stewart and Gilfix methodology. Results: Net metabolic acidosis, lactic acidosis, acidosis owing to unmeasured anions, acidemia, and dilutional acidosis were less frequent in the non-survival group compared to the survival group of CICPs. The presence of acidemia, acidosis owing to unmeasured anions, and lactic acidosis were independently associated with increased risk of intensive care unit 30-day mortality, with hazard ratios of 2.11 (95% confidence interval (CI): 1.43-3.12), 3.38 (95% CI: 2.36-4.84), and 2.16 (95% CI: 1.47-3.35), respectively. After full adjustment for confounders, the relationship between acidosis owing to unmeasured anions with hospital mortality was still significant, with hazard ratio of 2.29 (95% CI: 1.22-4.30). Furthermore, arterial lactate concentration in combination with chronic liver failure-sequential organ failure assessment and BE_UMA had the strongest ability to differentiate 30-day mortality (area under the receiver operating characteristic curve: 0.79, 95% CI: 0.74-0.83). Conclusions: CICPs with AKI exhibit a complex metabolic acidosis during intensive care unit admission. Lactic acidosis and BE_UMA, novel markers of acid-base disorders, show promise in predicting mortality rate of CICPs with AKI.