Outcomes Among Patients Transferred for Revascularization With Impella for Acute Myocardial Infarction With Cardiogenic Shock from the cVAD Registry

Need for Support: Facilitating Early Transfer of Cardiogenic Shock Patients to Advanced Heart Failure Centres

Background

Cardiogenic shock (CS) is a complex, life-threatening condition that requires timely care of patients. The purpose of this study is to evaluate the characteristics and outcomes of patients transferred to a cardiac intensive-care unit from outside hospitals, compared to those of patients admitted directly to a CS centre.

Methods

Patients admitted with CS (January 1, 2014-December 31, 2019) were analyzed. Clinical characteristics and outcomes were recorded.

Results

A total of 916 patients were admitted with CS; 440 (48.0%) were transferred from outside hospitals, and 476 (52.0%) were admitted directly to our institution. Transferred patients were younger (56.5 ± 14.7 vs 63.3 ± 16.3 years, P < 0.001), required vasopressor support more often (63.6% vs 14.9%, P < 0.001), and required mechanical ventilation more often (40.6% vs 10.7%, P < 0.001) upon transfer to the cardiac intensive-care unit. Transferred patients more frequently required extracorporeal life support (8.9% vs 3.0%, P < 0.001), had a lower rate of requiring orthotopic heart transplantation (6.4% vs 14.6%, P < 0.001), and had a lower incidence of all-cause mortality during follow-up (52.3% vs 62.8%, P = 0.001). With a multivariate analysis, patients transferred from outside were found to be less likely to reach the composite endpoint of durable ventricular assist device, orthotopic heart transplantation, or death (hazard ratio 0.75, 95% confidence interval 0.62-0.90, P = 0.003).

Conclusions

Marked differences are present in the characteristics and outcomes of patients transferred from outside institutions vs of those transferred from within our quaternary-care centre. Further studies are required to evaluate decision-making for transfer of CS patients and assess CS outcomes in the setting of standardized CS protocols and interventions.

Comparison of in-hospital outcomes of ST-elevation myocardial infarction patients with cardiogenic shock receiving left ventricular mechanical circulatory support devices based on transfer status

BACKGROUND

We aimed to compare outcomes in patients who receive on-site left ventricular mechanical support versus those transferred to other facilities for mechanical support in ST-elevation myocardial infarction (STEMI) patients with cardiogenic shock.

METHODS

This retrospective study analyzed data from the 2016 to 2020 Nationwide Inpatient Sample (NIS) database. We identified patients with STEMI and cardiogenic shock who received Impella and LVAD placement during their hospital stay. They were divided into two groups: those with in-house (direct) placement and those transferred to higher-level medical centers. The primary goal was to compare mortality rates between these groups.

RESULTS

During the study, 15,934 (75.2%) received in-house left ventricular support, while 5255 (24.8%) were transferred. Mean age (63 vs. 64 years) and female percentage (25 vs. 26%) were similar. The average time from admission to receiving LV support was 0.8 days for direct group versus 2.8 days for transfer group (p < 0.001). Transferred patients had a higher rate of prior heart failure (68 vs. 79%, p < 0.001) and peripheral vascular disease (10 vs. 14%, p < 0.001) but a lower rate of hypertension (23 vs. 17%, p = 0.003). There were no significant differences in other comorbidities. Primary outcome mortality did not significantly differ (44.9 vs. 44.2, p = 0.66). After multivariate analysis, transferred patients had higher rates of ECMO usage, acute kidney injury, renal replacement therapy, major bleeding, and ischemic stroke. Length of stay (8 vs. 15 days, p < 0.001) and total charges ($391,472 vs. $581,183, p < 0.001) were significantly higher in the transferred group.

CONCLUSION

Among STEMI patients with cardiogenic shock, our study found no significant difference in mortality between patients transferred for and those with on-site LV support. Those transferred patients experienced more complications, longer length of stay, and increased hospital costs.

Percutaneous Mechanical Circulatory Support in Acute Heart Failure Complicated with Cardiogenic Shock

Despite advancements in algorithms concerning the management of cardiogenic shock, current guidelines still lack the adequate integration of mechanical circulatory support devices. In recent years, more and more devices have been developed to provide circulatory with or without respiratory support, when conservative treatment with inotropic agents and vasopressors has failed. Mechanical circulatory support can be contemplated for patients with severe, refractory, or acute-coronary-syndrome-related cardiogenic shock. Through this narrative review, we delve into the differences among the types of currently used devices by presenting their notable advantages and inconveniences. We address the technical issues emerging while choosing the best possible device, temporarily as a bridge to another treatment plan or as a destination therapy, in the optimal timing for each type of patient. We also highlight the diverse implantation and removal techniques to avoid major complications such as bleeding and limb ischemia. Ultimately, we hope to shed some light in the gaps of evidence and the importance of conducting further organized studies around the topic of mechanical circulatory support when dealing with such a high mortality rate.

Impella Versus VA-ECMO for Patients with Cardiogenic Shock: Comprehensive Systematic Literature Review and Meta-Analyses

Impella and VA-ECMO are two possible therapeutic courses for the treatment of patients with cardiogenic shock (CS). The study aims to perform a systematic literature review and meta-analyses of a comprehensive set of clinical and socio-economic outcomes observed when using Impella or VA-ECMO with patients under CS. A systematic literature review was performed in Medline, and Web of Science databases on 21 February 2022. Nonoverlapping studies with adult patients supported for CS with Impella or VA-ECMO were searched. Study designs including RCTs, observational studies, and economic evaluations were considered. Data on patient characteristics, type of support, and outcomes were extracted. Additionally, meta-analyses were performed on the most relevant and recurring outcomes, and results shown using forest plots. A total of 102 studies were included, 57% on Impella, 43% on VA-ECMO. The most common outcomes investigated were mortality/survival, duration of support, and bleeding. Ischemic stroke was lower in patients treated with Impella compared to the VA-ECMO population, with statistically significant difference. Socio-economic outcomes including quality of life or resource use were not reported in any study. The study highlighted areas where further data collection is needed to clarify the value of complex, new technologies in the treatment of CS that will enable comparative assessments focusing both on the health impact on patient outcomes and on the financial burden for government budgets. Future studies need to fill the gap to comply with recent regulatory updates at the European and national levels.

A Standardized and Regionalized Network of Care for Cardiogenic Shock

BACKGROUND

The benefits of standardized care for cardiogenic shock (CS) across regional care networks are poorly understood.

OBJECTIVES

The authors compared the management and outcomes of CS patients initially presenting to hub versus spoke hospitals within a regional care network.

METHODS

The authors stratified consecutive patients enrolled in their CS registry (January 2017 to December 2019) by presentation to a spoke versus the hub hospital. The primary endpoint was 30-day mortality. Secondary endpoints included bleeding, stroke, or major adverse cardiovascular and cerebrovascular events.

RESULTS

Of 520 CS patients, 286 (55%) initially presented to 34 spoke hospitals. No difference in mean age (62 years vs 61 years; P = 0.38), sex (25% vs 32% women; P = 0.10), and race (54% vs 52% white; P = 0.82) between spoke and hub patients was noted. Spoke patients more often presented with acute myocardial infarction (50% vs 32%; P < 0.01), received vasopressors (74% vs 66%; P = 0.04), and intra-aortic balloon pumps (88% vs 37%; P < 0.01). Hub patients were more often supported with percutaneous ventricular assist devices (44% vs 11%; P < 0.01) and veno-arterial extracorporeal membrane oxygenation (13% vs 0%; P < 0.01). Initial presentation to a spoke was not associated with increased risk-adjusted 30-day mortality (adjusted OR: 0.87 [95% CI: 0.49-1.55]; P = 0.64), bleeding (adjusted OR: 0.89 [95% CI: 0.49-1.62]; P = 0.70), stroke (adjusted OR: 0.74 [95% CI: 0.31-1.75]; P = 0.49), or major adverse cardiovascular and cerebrovascular events (adjusted OR 0.83 [95% CI: 0.50-1.35]; P = 0.44).

CONCLUSIONS

Spoke and hub patients experienced similar short-term outcomes within a regionalized CS network. The optimal strategy to promote standardized care and improved outcomes across regional CS networks merits further investigation.

Impact of hospital transfer to hubs on outcomes of cardiogenic shock in the real world

AIMS

Cardiogenic shock (CS) is associated with significant mortality, and there is a movement towards regional 'hub-and-spoke' triage systems to coordinate care and resources. Limited data exist on outcomes of patients treated at CS transfer hubs.

METHODS AND RESULTS

Cardiogenic shock hospitalizations were obtained from the Nationwide Readmissions Database 2010-2014. Centres receiving any interhospital transfers with CS in a given year were classified as CS transfer 'hubs'; those without transfers were classified as 'spokes.' In-hospital mortality was compared among three cohorts: (A) direct admissions to spokes, (B) direct admissions to hubs, and (C) interhospital transfer to hubs. Among hospitals treating CS, 70.6% were classified as spokes and 29.4% as hubs. A total of 130 656 (31.7%) hospitalizations with CS were direct admission to spokes, 253 234 (61.4%) were direct admissions to hubs, and 28 777 (7.0%) were transfer to hubs. CS mortality was 47.8% at spoke hospitals and was lower at hub hospitals, both for directly admitted (39.3%, P < 0.01) and transferred (33.4%, P < 0.01) patients. Hospitalizations at hubs had higher procedural frequency (including coronary artery bypass graft, right heart catheterization, mechanical circulatory support), greater length of stay, and greater costs. On multivariable analysis, direct admission to CS hubs [odds ratio (OR) 0.86, 95% confidence interval (CI) 0.84-0.89, P < 0.01] and transfer to hubs (OR 0.72, 95% CI 0.69-0.76, P < 0.01) were both associated with lower mortality.

CONCLUSION

While acknowledging the limited ability of the Nationwide Readmissions Database to classify CS severity on presentation, treatment of CS at transfer hubs was associated with significantly lower mortality within this large real-world sample.

European Resuscitation Council and European Society of Intensive Care Medicine guidelines 2021: post-resuscitation care

The European Resuscitation Council (ERC) and the European Society of Intensive Care Medicine (ESICM) have collaborated to produce these post-resuscitation care guidelines for adults, which are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. The topics covered include the post-cardiac arrest syndrome, diagnosis of cause of cardiac arrest, control of oxygenation and ventilation, coronary reperfusion, haemodynamic monitoring and management, control of seizures, temperature control, general intensive care management, prognostication, long-term outcome, rehabilitation and organ donation.

European Resuscitation Council and European Society of Intensive Care Medicine Guidelines 2021: Post-resuscitation care

The European Resuscitation Council (ERC) and the European Society of Intensive Care Medicine (ESICM) have collaborated to produce these post-resuscitation care guidelines for adults, which are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. The topics covered include the post-cardiac arrest syndrome, diagnosis of cause of cardiac arrest, control of oxygenation and ventilation, coronary reperfusion, haemodynamic monitoring and management, control of seizures, temperature control, general intensive care management, prognostication, long-term outcome, rehabilitation, and organ donation.

The Partial Support of the Left Ventricular Assist Device Shifts the Systemic Cardiac Output Curve Upward in Proportion to the Effective Left Ventricular Ejection Fraction in Pressure-Volume Loop

Left ventricular assist device (LVAD) has been saving many lives in patients with severe left ventricular (LV) failure. Recently, a minimally invasive transvascular LVAD such as Impella enables us to support unstable hemodynamics in severely ill patients. Although LVAD support increases total LV cardiac output (CO_TLV) at the expense of decreases in the native LV cardiac output (CO_NLV), the underlying mechanism determining CO_TLV remains unestablished. This study aims to clarify the mechanism and develop a framework to predict CO_TLV under known LVAD flow (CO_LVAD). We previously developed a generalized framework of circulatory equilibrium that consists of the integrated CO curve and the VR surface as common functions of right atrial pressure (P_RA) and left atrial pressure (P_LA). The intersection between the integrated CO curve and the VR surface defines circulatory equilibrium. Incorporating LVAD into this framework indicated that LVAD increases afterload, which in turn decreases CO_NLV. The total LV cardiac output (CO_TLV) under LVAD support becomes CO_TLV = CO_NLV+EF_e · CO_LVAD, where EF_e is effective ejection fraction, i.e., E_es/(E_es+E_a). E_es and E_a represent LV end-systolic elastance (E_es) and effective arterial elastance (E_a), respectively. In other words, LVAD shifts the total LV cardiac output curve upward by EF_e · CO_LVAD. In contrast, LVAD does not change the VR surface or the right ventricular CO curve. In six anesthetized dogs, we created LV failure by the coronary ligation of the left anterior descending artery and inserted LVAD by withdrawing blood from LV and pumping out to the femoral artery. We determined the parameters of the CO curve with a volume-change technique. We then changed the CO_LVAD stepwise from 0 to 70–100 ml/kg/min and predicted hemodynamics by using the proposed circulatory equilibrium. Predicted CO_TLV, P_RA, and P_LA for each step correlated well with those measured (SEE; 2.8 ml/kg/min 0.17 mmHg, and 0.65 mmHg, respectively, r²; 0.993, 0.993, and 0.965, respectively). The proposed framework quantitatively predicted the upward-shift of the total CO curve resulting from the synergistic effect of LV systolic function and LVAD support. The proposed framework can contribute to the safe management of patients with LVAD.