Outcomes Associated with Respiratory Failure for Patients with Cardiogenic Shock and Acute Myocardial Infarction: A Substudy of the CULPRIT-SHOCK Trial

Tracheostomy in Patients with Acute Myocardial Infarction and Respiratory Failure

OBJECTIVE

Patients with acute myocardial infarction (AMI) complicated by respiratory failure require antiplatelet regimens which often cannot be stopped and may increase bleeding from tracheostomy. However, there is limited available data on both the proportion of patients undergoing tracheostomy and the impact on antiplatelet regimens on outcomes.

METHODS

Utilizing the Vizient® Clinical Data Base, we identified patients ≥18 years admitted from 2015 to 2019 with a primary diagnosis of AMI and requiring invasive mechanical ventilation (IMV). We assessed for the incidence of patients undergoing tracheostomy, outcomes stratified by the timing of tracheostomy (≤10 vs >10 days), and the association between dual antiplatelet therapy (DAPT) use and in-hospital mortality.

RESULTS

We identified 26 435 patients presenting with AMI requiring IMV. The mean (SD) age was 66.8 (12.3) years and 33.4% were women. The incidence of tracheostomy was 6.0% (n = 1573), and the median IMV time to tracheostomy was 12 days, 55.6% of which underwent percutaneous and 44.4% underwent open tracheostomy. Over 90% (n = 1424) underwent tracheostomy (>10 days) and had a similar mortality when compared to early (≤10 days) tracheostomy (22.5% vs 22.8%, P = 0.94). On the day of tracheostomy, only 24.7% were given DAPT, which was associated with a lower mortality than those not on DAPT (17.4% vs 23.7%, P = 0.01). After multivariable adjustment, DAPT use on the day of tracheostomy remained associated with lower in-hospital mortality (odds ratio 0.68; 95% confidence interval: 0.49-0.94, P = 0.02). Tracheostomy complications were not different between groups (P > 0.05), but more patients in the DAPT group required post-tracheostomy blood transfusions (5.6% vs 2.7%, P = 0.01).

CONCLUSION

Approximately 1 in 20 intubated AMI patients requires tracheostomy. The lack of DAPT interruption on the day of tracheostomy but not the timing of tracheostomy was associated with a lower in-hospital mortality. Our results suggest that DAPT should not be a barrier to tracheostomy for patients with AMI.

Ventilation strategies in cardiogenic shock: insights from the FRENSHOCK observational registry

BACKGROUND

Despite scarce data, invasive mechanical ventilation (MV) is widely suggested as first-line ventilatory support in cardiogenic shock (CS) patients. We assessed the real-life use of different ventilation strategies in CS and their influence on short and mid-term prognosis.

METHODS

FRENSHOCK was a prospective registry including 772 CS patients from 49 centers in France. Patients were categorized into three groups according to the ventilatory supports during hospitalization: no mechanical ventilation group (NV), non-invasive ventilation alone group (NIV), and invasive mechanical ventilation group (MV). We compared clinical characteristics, management, and occurrence of death and major adverse event (MAE) (death, heart transplantation or ventricular assist device) at 30 days and 1 year between the three groups.

RESULTS

Seven hundred sixty-eight patients were included in this analysis. Mean age was 66 years and 71% were men. Among them, 359 did not receive any ventilatory support (46.7%), 118 only NIV (15.4%), and 291 MV (37.9%). MV patients presented more severe CS with more skin mottling, higher lactate levels, and higher use of vasoactive drugs and mechanical circulatory support. MV was associated with higher mortality and MAE at 30 days (HR 1.41 [1.05-1.90] and 1.52 [1.16-1.99] vs NV). No difference in mortality (HR 0.79 [0.49-1.26]) or MAE (HR 0.83 [0.54-1.27]) was found between NIV patients and NV patients. Similar results were found at 1-year follow-up.

CONCLUSIONS

Our study suggests that using NIV is safe in selected patients with less profound CS and no other MV indication. NCT02703038.

Arterial hyperoxia and mortality in the cardiac intensive care unit

BACKGROUND

Arterial hyperoxia (hyperoxemia), defined as a high arterial partial pressure of oxygen (PaO2), has been associated with adverse outcomes in critically ill populations, but has not been examined in the cardiac intensive care unit (CICU). We evaluated the association between exposure to hyperoxia on admission with in-hospital mortality in a mixed CICU cohort.

METHODS

We included unique Mayo Clinic CICU patients admitted from 2007 to 2018 with admission PaO2 data (defined as the PaO2 value closest to CICU admission) and no hypoxia (PaO2 < 60mmHg). The admission PaO2 was evaluated as a continuous variable and categorized (60-100 mmHg, 101-150 mmHg, 151-200 mmHg, 201-300 mmHg, >300 mmHg). Logistic regression was used to evaluate predictors of in-hospital mortality before and after multivariable adjustment.

RESULTS

We included 3,368 patients with a median age of 70.3 years; 70.3% received positive-pressure ventilation. The median PaO2 was 99 mmHg, with a distribution as follows: 60-100 mmHg, 51.9%; 101-150 mmHg, 28.6%; 151-200 mmHg, 10.6%; 201-300 mmHg, 6.4%; >300 mmHg, 2.5%. A J-shaped association between admission PaO2 and in-hospital mortality was observed, with a nadir around 100 mmHg. A higher PaO2 was associated with increased in-hospital mortality (adjusted OR 1.17 per 100 mmHg higher, 95% CI 1.01-1.34, p = 0.03). Patients with PaO2 >300 mmHg had higher in-hospital mortality versus PaO2 60-100 mmHg (adjusted OR 2.37, 95% CI 1.41-3.94, p < 0.001).

CONCLUSIONS

Hyperoxia at the time of CICU admission is associated with higher in-hospital mortality, primarily in those with severely elevated PaO2 >300 mmHg.

Ventilation strategies in cardiogenic shock: Insights from the AltShock-2 registry

AIMS

To describe the use and the relation to outcome of different ventilation strategies in a contemporary, large, prospective registry of cardiogenic shock patients.

METHODS AND RESULTS

Among 657 patients enrolled from March 2020 to November 2023, 198 (30.1%) received oxygen therapy (OT), 96 (14.6%) underwent non-invasive ventilation (NIV), and 363 (55.3%) underwent invasive mechanical ventilation (iMV). Patients in the iMV group were significantly younger compared to those in the NIV and OT groups (63 vs. 69 years, p < 0.001). There were no significant differences between groups regarding cardiovascular risk factors. Patients with SCAI B and C were more frequently treated with OT and NIV compared to iMV (65.1% and 65.4% vs. 42.6%, respectively, p > 0.001), while the opposite trend was observed in SCAI D patients (12% and 12.2% vs. 30.9%, respectively, p < 0.001). All-cause mortality at 24 h did not differ amongst the three groups. The 60-day mortality rates were 40.2% for the iMV group, 26% for the OT group, and 29.3% for the NIV group (p = 0.005), even after excluding patients with cardiac arrest at presentation. In the multivariate analysis including SCAI stages, NIV was not associated with worse mortality compared to iMV (hazard ratio 1.97, 95% confidence interval 0.85-4.56), even in more severe SCAI stages such as D.

CONCLUSIONS

Compared to previous studies, we observed a rising trend in the utilization of NIV among cardiogenic shock patients, irrespective of aetiology and SCAI stages. In this clinical scenario, NIV emerges as a safe option for appropriately selected patients.

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.

Extra-cardiac management of cardiogenic shock in the intensive care unit

Cardiogenic shock (CS) is a heterogeneous clinical syndrome characterized by low cardiac output leading to end-organ hypoperfusion. Organ dysoxia ranging from transient organ injury to irreversible organ failure and death occurs across all CS etiologies but differing by incidence and type. Herein, we review the recognition and management of respiratory, renal and hepatic failure complicating CS. We also discuss unmet needs in the CS care pathway and future research priorities for generating evidence-based best practices for the management of extra-cardiac sequelae. The complexity of CS admitted to the contemporary cardiac intensive care unit demands a workforce skilled to care for these extra-cardiac critical illness complications with an appreciation for how cardio-systemic interactions influence critical illness outcomes in afflicted patients.

Invasive mechanical ventilation in cardiogenic shock complicating acute myocardial infarction: A contemporary Danish cohort analysis

PURPOSE

Invasive mechanical ventilation (IMV) is widely used in patients with cardiogenic shock following acute myocardial infarction (AMICS), but evidence to guide practice remains sparse. We sought to evaluate trends in the rate of IMV utilization, applied settings, and short term-outcome of a contemporary cohort of AMICS patients treated with IMV according to out-of-hospital cardiac arrest (OHCA) at admission.

METHODS

Consecutive AMICS patients receiving IMV in an intensive care unit (ICU) at two tertiary centres between 2010 and 2017. Data were analysed in relation to OHCA.

RESULTS

A total of 1274 mechanically ventilated AMICS patients were identified, 682 (54%) with OHCA. Frequency of IMV increased during the study period, primarily due to higher occurrence of OHCA admissions. Among 566 patients with complete ventilator data, positive-end-expiratory pressure, inspired oxygen fraction, and minute ventilation during the initial 24 h in ICU were monitored. No differences were observed between 30-day survivors and non-survivors with OHCA. In non-OHCA, these ventilator requirements were significantly higher among 30-day non-survivors (P for all<0.05), accompanied by a lower PaO2/FiO2 ratio (median 143 vs. 230, P < 0.001) and higher arterial lactate levels (median 3.5 vs. 1.5 mmol/L, P < 0.001) than survivors. Physiologically normal PaO2 and pCO2 levels were achieved in all patients irrespective of 30-day survival and OHCA status.

CONCLUSION

In the present contemporary cohort of AMICS patients, physiologically normal blood gas values were achieved both in OHCA and non-OHCA in the early phase of admission. However, increased demand of ventilatory support was associated with poorer survival only in non-OHCA patients.

Propofol vs etomidate for induction prior to invasive mechanical ventilation in patients with acute myocardial infarction

BACKGROUND

Patients with acute myocardial infarction (AMI) requiring invasive mechanical ventilation (IMV) have a high mortality. However, little is known regarding the impact of induction agents, used prior to IMV, on clinical outcomes in this population. We assessed for the association between induction agent and mortality in patients with AMI requiring IMV.

METHODS

We compared clinical outcomes between those receiving propofol compared to etomidate for induction among adults with AMI between October 2015 and December 2019 using the Vizient® Clinical Data Base, a multicenter, US national database. We used inverse probability treatment weighting (IPTW) to assess for the association between induction agent and in-hospital mortality.

RESULTS

We identified 5,147 patients, 1,386 (26.9%) of received propofol and 3,761 (73.1%) received etomidate for IMV induction. The mean (SD) age was 66.1 (12.4) years, 33.0% were women, and 51.6% and 39.8% presented with STEMI and cardiogenic shock, respectively. Patients in the propofol group were more likely to require preintubation vasoactive medication and mechanical circulatory support (both, P < .05). Utilization of propofol was associated with lower mortality compared to etomidate (32.3% vs 36.1%, P = .01). After propensity weighting, propofol use remained associated with lower mortality (weighted mean difference -4.7%; 95% confidence interval: -7.6% to -1.8%, P = .002). Total cost, ventilator days, and length of stay were higher in the propofol group (all, P < .001).

CONCLUSIONS

Induction with propofol, compared with etomidate, was associated with lower mortality for patients with AMI requiring IMV. Randomized trials are needed to determine the optimal induction agent for this critically ill patient population.

Noninvasive Ventilation in the Cardiac Intensive Care Unit

Over the last several decades, the cardiac intensive care unit (CICU) has seen an increase in the complexity of the patient population and etiologies requiring CICU admission. Currently, respiratory failure is the most common reason for admission to the contemporary CICU. As a result, noninvasive ventilation (NIV), including noninvasive positive-pressure ventilation and high-flow nasal cannula, has been increasingly utilized in the management of patients admitted to the CICU. In this review, we detail the different NIV modalities and summarize the evidence supporting their use in conditions frequently encountered in the CICU. We describe the unique pathophysiologic interactions between positive pressure ventilation and left and/or right ventricular dysfunction. Additionally, we discuss the evidence and strategies for utilization of NIV as a method to reduce extubation failure in patients who required invasive mechanical ventilation. Lastly, we examine unique considerations for managing respiratory failure in certain, high-risk patient populations such as those with right ventricular failure, severe valvular disease, and adult congenital heart disease. Overall, it is critical for clinicians who practice in the CICU to be experts with the application, risks, benefits, and modalities of NIV in cardiac patients with respiratory failure.

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.

Stress Ulcer Prophylaxis in Mechanically Ventilated Patients With Acute Myocardial Infarction

Background

Proton pump inhibitors (PPIs) and histamine type 2-receptor blockers (H2Bs) are commonly used for stress ulcer prophylaxis among patients requiring invasive mechanical ventilation (IMV). Recent studies suggest an increased mortality associated with PPIs compared to H2Bs, but these studies poorly represent patients with cardiovascular disease or acute myocardial infarction (AMI).

Objectives

The aim of this study was to compare outcomes related to stress ulcer prophylaxis with PPIs compared to H2Bs in patients with AMI requiring IMV.

Methods

We queried the Vizient Clinical Data Base for adults aged ≥18 years admitted between October 2015 and December 2019 with a primary diagnosis of AMI and requiring IMV. Using multivariable logistic regression, we assessed for the association between stress ulcer prophylaxis and in-hospital mortality.

Results

Including 11,252 patients with AMI requiring IMV, 66.7% (n = 7,504) received PPIs and 33.3% (n = 3,748) received H2Bs. Age, sex, and the proportion of patients presenting with ST-segment elevation myocardial infarction or cardiogenic shock were similar between groups (all, P > 0.05). Compared to PPIs, patients receiving H2Bs had a lower mortality (41.5% vs 43.5%, P = 0.047), which was not statistically significant after multivariate adjustment (odds ratio 0.97; 95% confidence interval: 0.89-1.06, P = 0.49). In unadjusted and adjusted analyses, H2Bs use was associated with fewer ventilator days, less ventilator-associated pneumonia, and lower hospitalization cost but similar Clostridium difficile infections.

Conclusions

Among patients with AMI requiring IMV in this observation cohort study, there was no difference in mortality among patients receiving H2Bs vs PPIs for stress ulcer prophylaxis despite fewer ventilator days and lower ventilator-associated pneumonia in those receiving H2Bs.

Clinical Outcomes and Cost Associated With an Intravascular Microaxial Left Ventricular Assist Device vs Intra-aortic Balloon Pump in Patients Presenting With Acute Myocardial Infarction Complicated by Cardiogenic Shock

Importance

Intravascular microaxial left ventricular assist device (LVAD) compared with intra-aortic balloon pump (IABP) has been associated with increased risk of mortality and bleeding among patients with acute myocardial infarction (AMI) and cardiogenic shock (CS) undergoing percutaneous coronary intervention (PCI). However, evidence on the association of device therapy with a broader array of clinical outcomes, including data on long-term outcomes and cost, is limited.

Objective

To examine the association between intravascular LVAD or IABP use and clinical outcomes and cost in patients with AMI complicated by CS.

Design, Setting, and Participants

This retrospective propensity-matched cohort study used administrative claims data for commercially insured patients from 14 states across the US. Patients included in the analysis underwent PCI for AMI complicated by CS from January 1, 2015, to April 30, 2020. Data analysis was performed from April to November 2021.

Exposures

Use of either an intravascular LVAD or IABP.

Main Outcomes and Measures

The primary outcomes were mortality, stroke, severe bleeding, repeat revascularization, kidney replacement therapy (KRT), and total health care costs during the index admission. Clinical outcomes and cost were also assessed at 30 days and 1 year.

Results

Among 3077 patients undergoing PCI for AMI complicated by CS, the mean (SD) age was 65.2 (12.5) years, and 986 (32.0%) had cardiac arrest. Among 817 propensity-matched pairs, intravascular LVAD use was associated with significantly higher in-hospital (36.2% vs 25.8%; odds ratio [OR], 1.63; 95% CI, 1.32-2.02), 30-day (40.1% vs 28.3%; OR, 1.71; 95% CI, 1.37-2.13), and 1-year mortality (58.9% vs 45.0%; hazard ratio [HR], 1.44; 95% CI, 1.21-1.71) compared with IABP. At 30 days, intravascular LVAD use was associated with significantly higher bleeding (19.1% vs 14.5%; OR, 1.35; 95% CI, 1.04-1.76), KRT (12.2% vs 7.0%; OR, 1.88; 95% CI, 1.30-2.73), and mean cost (+$51 680; 95% CI, $31 488-$75 178). At 1 year, the association of intravascular LVAD use with bleeding (29.7% vs 24.3%; HR, 1.36; 95% CI, 1.05-1.75), KRT (18.1% vs 10.9%; HR, 1.95; 95% CI, 1.35-2.83), and mean cost (+$46 609; 95% CI, $22 126-$75 461) persisted.

Conclusions and Relevance

In this propensity-matched analysis of patients undergoing PCI for AMI complicated by CS, intravascular LVAD use was associated with increased short-term and 1-year risk of mortality, bleeding, KRT, and cost compared with IABP. There is an urgent need for additional evidence surrounding the optimal management of patients with AMI complicated by CS.

Complicating Acute Myocardial Infarction. Current Status and Unresolved Targets for Subsequent Research

Mechanical reperfusion with primary angioplasty, as the treatment of choice in acute myocardial infarction (MI), is associated not only with a high percentage of full epicardial and tissue reperfusion but also with a very good immediate and long-term clinical outcome. However, the Achilles heel of MI treatment is its ensemble of complications, such as cardiogenic shock due to severe systolic and/or diastolic dysfunction or MI mechanical complications, including perforation of the left ventricular free wall, papillary muscle rupture with acute mitral regurgitation and ventricular septal rupture. They are associated with an increased or, sometimes, with an extremely high mortality rate, determining the overall mortality in an MI patient population. In this review we summarize the mechanisms of MI complications, current therapeutic management and alternative directions for overcoming their devastating consequences. Moreover, we have sought to indicate gaps in the evidence on current treatments as the potential targets for further clinical research. From the perspective of mortality trends that are not improving, the forthcoming therapeutic management of complicated MI will require an individualized and novel approach based on their thorough pathobiology.

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.

Trends in Therapy and Outcomes Associated With Respiratory Failure in Patients Admitted to the Cardiac Intensive Care Unit

PURPOSE

To describe the epidemiology, outcomes, and temporal trends of respiratory failure in the cardiac intensive care unit (CICU).

MATERIALS AND METHODS

Retrospective cohort analysis of 2,986 unique Mayo Clinic CICU patients from 2007 to 2018 with respiratory failure. Temporal trends were analyzed, along with hospital and 1-year mortality. Multivariable logistic regression was used to determine adjusted hospital mortality trends.

RESULTS

The prevalence of respiratory failure in the CICU increased from 15% to 38% during the study period (P < 0.001 for trend). Among patients with respiratory failure, the utilization of invasive ventilation decreased and noninvasive ventilation modalities increased over time. Hospital mortality and 1-year mortality were 24% and 54%, respectively, with variation according to the type of respiratory support (highest among patients receiving invasive ventilation alone: 35% and 46%, respectively). Hospital mortality was highest among patients with concomitant cardiac arrest and/or shock (52% for patients with both). Hospital mortality decreased in the overall population from 35% to 25% (P < 0.001 for trend), but was unchanged among patients receiving positive-pressure ventilation.

CONCLUSIONS

The prevalence of respiratory failure in CICU more than doubled during the last decade. The use of noninvasive respiratory support increased, while overall mortality declined over time. Cardiac arrest and shock accounted for the majority of deaths. Further research is needed to optimize the outcomes of high-risk CICU patients with respiratory failure.