Venoarterial Extracorporeal Membrane Oxygenation Support for Ventricular Tachycardia Ablation: A Systematic Review

Short-term and long-term outcomes of cardiac arrhythmias in patients with cardiogenic shock

INTRODUCTION

Cardiogenic shock is severe circulatory failure that results in significant in-hospital mortality, related morbidity, and economic burden. Patients with cardiogenic shock are at high risk for atrial and ventricular arrhythmias, particularly within the subset of patients with an overlap of cardiogenic shock and cardiac arrest.

AREAS COVERED

This review article will explore the prevalence, definition, management, and outcomes of common arrhythmias in patients with cardiogenic shock. This review will describe the pathophysiology of arrhythmia in cardiogenic shock and the impact of inotropic agents on increased arrhythmogenicity. In addition to medical management, focused assessment of mechanical circulatory support, radiofrequency ablation, deep sedation, and stellate ganglion block will be provided.

EXPERT OPINION

We will navigate the limited data and describe the prognostic impacts of arrhythmia. Finally, we will conclude the review with a discussion of prevention strategies, research limitations, and future research directions.

Need for a Cardiogenic Shock Team Collaborative-Promoting a Team-Based Model of Care to Improve Outcomes and Identify Best Practices

Cardiogenic shock continues to carry a high mortality rate despite contemporary care, with no breakthrough therapies shown to improve survival over the past few decades. It is a time-sensitive condition that commonly results in cardiovascular complications and multisystem organ failure, necessitating multidisciplinary expertise. Managing patients with cardiogenic shock remains challenging even in well-resourced settings, and an important subgroup of patients may require cardiac replacement therapy. As a result, the idea of leveraging the collective cognitive and procedural proficiencies of multiple providers in a collaborative, team-based approach to care (the "shock team") has been advocated by professional societies and implemented at select high-volume clinical centers. A slowly maturing evidence base has suggested that cardiogenic shock teams may improve patient outcomes. Although several registries exist that are beginning to inform care, particularly around therapeutic strategies of pharmacologic and mechanical circulatory support, none of these are currently focused on the shock team approach, multispecialty partnership, education, or process improvement. We propose the creation of a Cardiogenic Shock Team Collaborative-akin to the successful Pulmonary Embolism Response Team Consortium-with a goal to promote sharing of care protocols, education of stakeholders, and discovery of how process and performance may influence patient outcomes, quality, resource consumption, and costs of care.

Mechanical Support Strategies for High-Risk Procedures in the Invasive Cardiac Catheterization Laboratory: A State-of-the-Art Review

Thanks to advancements in percutaneous cardiac interventions, an expanding patient population now qualifies for treatment through percutaneous endovascular procedures. High-risk interventions far exceed coronary interventions and include transcatheter aortic valve replacement, endovascular management of acute pulmonary embolism and ventricular tachycardia ablation. Given the frequent impairment of ventricular function in these patients, frequently deteriorating during percutaneous interventions, it is hypothesized that mechanical ventricular support may improve periprocedural survival and subsequently patient outcome. In this narrative review, we aimed to provide the relevant evidence found for the clinical use of percutaneous mechanical circulatory support (pMCS). We searched the Pubmed database for articles related to pMCS and to pMCS and invasive cath lab procedures. The articles and their references were evaluated for relevance. We provide an overview of the clinically relevant evidence for intra-aortic balloon pump, Impella, TandemHeart and ECMO and their role as pMCS in high-risk percutaneous coronary intervention, transcatheter valvular procedures, ablations and high-risk pulmonary embolism. We found that the right choice of periprocedural pMCS could provide a solution for the hemodynamic challenges during these procedures. However, to enhance the understanding of the safety and effectiveness of pMCS devices in an often high-risk population, more randomized research is needed.

Guiding ablation strategies for ventricular tachycardia in patients with structural heart disease by analyzing links and conversion patterns of traceable abnormal late potential zone

BACKGROUND

Substrate-based ablation can treat uninducible or hemodynamically instability scar-related ventricular tachycardia (VT). However, whether a correlation exists between the critical VT isthmus and late activation zone (LAZ) during sinus rhythm (SR) is unknown.

OBJECTIVE

To demonstrate the structural and functional properties of abnormal substrates and analyze the link between the VT circuit and abnormal activity during SR.

METHODS

Thirty-six patients with scar-related VT (age, 50.0 ± 13.7 years and 86.1% men) who underwent VT ablation were reviewed. The automatic rhythmia ultrahigh resolution mapping system was used for electroanatomic substrate mapping. The clinical characteristics and mapping findings, particularly the LAZ characteristics during SR and VT, were analyzed. To determine the association between the LAZ during the SR and VT circuits, the LAZ was defined as five activation patterns: entrance, exit, core, blind alley, and conduction barrier.

RESULTS

Forty-five VTs were induced in 36 patients, 91.1% of which were monomorphic. The LAZ of all patients was mapped during the SR and VT circuits, and the consistency of the anatomical locations of the LAZ and VT circuits was analyzed. Using the ultrahigh resolution mapping system, interconversion patterns, including the bridge, T, puzzle, maze, and multilayer types, were identified. VT ablation enabled precise ablation of abnormal late potential conduction channels.

CONCLUSION

Five interconversion patterns of the LAZ during the SR and VT circuits were summarized. These findings may help formulate more precise substrate-based ablation strategies for scar-related VT and shorter procedure times.

Multidisciplinary Critical Care Management of Electrical Storm: JACC State-of-the-Art Review

Electrical storm (ES) reflects life-threatening cardiac electrical instability with 3 or more ventricular arrhythmia episodes within 24 hours. Identification of underlying arrhythmogenic cardiac substrate and reversible triggers is essential, as is interrogation and programming of an implantable cardioverter-defibrillator, if present. Medical management includes antiarrhythmic drugs, beta-adrenergic blockade, sedation, and hemodynamic support. The initial intensity of these interventions should be matched to the severity of ES using a stepped-care algorithm involving escalating treatments for higher-risk presentations or recurrent ventricular arrhythmias. Many patients with ES are considered for catheter ablation, which may require the use of temporary mechanical circulatory support. Outcomes after ES are poor, including frequent ES recurrences and deaths caused by progressive heart failure and other cardiac causes. A multidisciplinary collaborative approach to the management of ES is crucial, and evaluation for heart transplantation or palliative care is often appropriate, even for patients who survive the initial episode.

The Use of Cardioprotective Devices and Strategies in Patients Undergoing Percutaneous Procedures and Cardiac Surgery

In the United States, about one million people are seen to visit the operating theater for cardiac surgery annually. However, nearly half of these visits result in complications such as renal, neurological, and cardiac injury of varying degrees. Historically, many mechanisms and approaches have been explored in attempts to reduce injuries associated with cardiac surgery and percutaneous procedures. Devices such as cardioplegia, mechanical circulatory support, and other methods have shown promising results in managing and preventing life-threatening cardiac-surgery-related outcomes such as heart failure and cardiogenic shock. Comparably, cardioprotective devices such as TandemHeart, Impella family devices, and venoarterial extracorporeal membrane oxygenation (VA-ECMO) have also been proven to show significant cardioprotection through mechanical support. However, their use as interventional agents in the prevention of hemodynamic changes due to cardiac surgery or percutaneous interventions has been correlated with adverse effects. This can lead to a rebound increased risk of mortality in high-risk patients who undergo cardiac surgery. Further research is necessary to delineate and stratify patients into appropriate cardioprotective device groups. Furthermore, the use of one device over another in terms of efficacy remains controversial and further research is necessary to assess device potential in different settings. Clinical research is also needed regarding novel strategies and targets, such as transcutaneous vagus stimulation and supersaturated oxygen therapy, aimed at reducing mortality among high-risk cardiac surgery patients. This review explores the recent advances regarding the use of cardioprotective devices in patients undergoing percutaneous procedures and cardiac surgery.

Temporary mechanical circulatory support devices: practical considerations for all stakeholders

Originally intended for life-saving salvage therapy, the use of temporary mechanical circulatory support (MCS) devices has become increasingly widespread in a variety of clinical settings in the contemporary era. Their use as a short-term, prophylactic support vehicle has expanded to include procedures in the catheterization laboratory, electrophysiology suite, operating room and intensive care unit. Accordingly, MCS device design and technology continue to develop at a rapid pace. In this Review, we describe the functionality, indications, management and complications associated with temporary MCS, together with scenario-specific utilization, goal-directed development and bioengineering of future devices. We address various considerations for the use of temporary MCS devices in both prophylactic and rescue scenarios, with input from stakeholders from various cardiovascular specialties, including interventional and heart failure cardiology, electrophysiology, cardiothoracic anaesthesiology, critical care and cardiac surgery.

Complications of catheter ablation for ventricular tachycardia

With the increasing literature demonstrating benefits of catheter ablation for ventricular tachycardia (VT), the number of patients undergoing VT ablation has increased dramatically. As VT ablation is being performed more routinely, operators must be aware of potential complications of VT ablation. This review delves deeper into the practice of VT ablation with a focus on periprocedural complications.

Anesthetic Management and Considerations for Electrophysiology Procedures

The number of electrophysiology (EP) procedures being performed has dramatically increased in recent years. This escalation necessitates a full understanding by the general anesthesiologist as to the risks, specific considerations, and comorbidities that accompany these now common procedures. Procedures reviewed in this article include atrial fibrillation and flutter ablation, supraventricular tachycardia ablation, ventricular tachycardia ablation, electrical cardioversion, pacemaker insertion, implantable cardioverter-defibrillator (ICD) insertion, and ICD lead extraction. General anesthetic considerations as well as procedure-specific concerns are discussed. Knowledge of these procedures will add to the anesthesiologist's armamentarium in safely caring for patients in the EP laboratory.

Best Practices for the Catheter Ablation of Ventricular Arrhythmias

Techniques for catheter ablation have evolved to effectively treat a range of ventricular arrhythmias. Pre-operative electrocardiographic and cardiac imaging data are very useful in understanding the arrhythmogenic substrate and can guide mapping and ablation. In this review, we focus on best practices for catheter ablation, with emphasis on tailoring ablation strategies, based on the presence or absence of structural heart disease, underlying clinical status, and hemodynamic stability of the ventricular arrhythmia. We discuss steps to make ablation safe and prevent complications, and techniques to improve the efficacy of ablation, including optimal use of electroanatomical mapping algorithms, energy delivery, intracardiac echocardiography, and selective use of mechanical circulatory support.

Contemporary Management of Complex Ventricular Arrhythmias

Percutaneous catheter ablation is an effective and safe therapy that can eliminate ventricular tachycardia, reducing the risks of both recurrent arrhythmia and shock therapies from a defibrillator. Successful ablation requires accurate identification of arrhythmic substrate and the effective delivery of energy to the targeted tissue. A thorough pre-procedural assessment is needed before considered 3D electroanatomical mapping can be performed. In contemporary practice, this must combine traditional electrophysiological techniques, such as activation and entrainment mapping, with more novel physiological mapping techniques for which there is an ever-increasing evidence base. Novel techniques to maximise energy delivery to the tissue must also be considered and balanced against their associated risks of complication. This review provides a comprehensive appraisal of contemporary practice and the evidence base that supports recent developments in mapping and ablation, while also considering potential future developments in the field.

Cardiogenic Shock Complicating ST-Segment Elevation Myocardial Infarction: An 18-Year Analysis of Temporal Trends, Epidemiology, Management, and Outcomes

BACKGROUND

There are limited data on the temporal trends, incidence, and outcomes of ST-segment-elevation myocardial infarction-cardiogenic shock (STEMI-CS).

METHODS

Adult (>18 years) STEMI-CS admissions were identified using the National Inpatient Sample (2000-2017) and classified by tertiles of admission year (2000-2005, 2006-2011, 2012-2017). Outcomes of interest included temporal trends, acute organ failure, cardiac procedures, in-hospital mortality, hospitalization costs, and length of stay.

RESULTS

In ∼4.3 million STEMI admissions, CS was noted in 368,820 (8.5%). STEMI-CS incidence increased from 5.8% in 2000 to 13.0% in 2017 (patient and hospital characteristics adjusted odds ratio [aOR] 2.45 [95% confidence interval {CI} 2.40-2.49]; P < 0.001). Multiorgan failure increased from 55.5% (2000-2005) to 74.3% (2012-2017). Between 2000 and 2017, coronary angiography and percutaneous coronary intervention use increased from 58.8% to 80.1% and 38.6% to 70.6%, whereas coronary artery bypass grafting decreased from 14.9% to 10.4% (all P < 0.001). Over the study period, the use of intra-aortic balloon pump (40.6%-37.6%) decreased, and both percutaneous left ventricular assist devices (0%-12.9%) and extra-corporeal membrane oxygenation (0%-2.8%) increased (all P < 0.001). In hospital mortality decreased from 49.6% in 2000 to 32.7% in 2017 (aOR 0.29 [95% CI 0.28-0.31]; P < 0.001). During the 18-year period, hospital lengths of stay decreased, hospitalization costs increased and use of durable left ventricular assist device /cardiac transplantation remained stable (P > 0.05).

CONCLUSIONS

In the United States, incidence of CS in STEMI has increased 2.5-fold between 2000 and 2017, while in-hospital mortality has decreased during the study period. Use of coronary angiography and PCI increased during the study period.

A Clinical Update on Vasoactive Medication in the Management of Cardiogenic Shock

This is a focused review looking at the pharmacological support in cardiogenic shock. There are a plethora of data evaluating vasopressors and inotropes in septic shock, but the data are limited for cardiogenic shock. This review article describes in detail the pathophysiology of cardiogenic shock, the mechanism of action of different vasopressors and inotropes emphasizing their indications and potential side effects. This review article incorporates the currently used specific risk-prediction models in cardiogenic shock as well as integrates data from many trials on the use of vasopressors and inotropes. Lastly, this review seeks to discuss the future direction for vasoactive medications in cardiogenic shock.

Veno-Arterial Extracorporeal Membrane Oxygenation in Patients with Fulminant Myocarditis: A Review of Contemporary Literature

Fulminant myocarditis is characterized by life threatening heart failure presenting as cardiogenic shock requiring inotropic or mechanical circulatory support to maintain tissue perfusion. There are limited data on the role of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in the management of fulminant myocarditis. This review seeks to evaluate the management of fulminant myocarditis with a special emphasis on the role and outcomes with VA-ECMO use.

Imaging for Temporary Mechanical Circulatory Support Devices

Heart failure is an important cause of mortality and morbidity in the world. Changes in organ allocation for solid thoracic (lung and heart) transplantation has increased the number of patients on mechanical circulatory support. Temporary mechanical support devices include devices tht support the circulation directly or indirectly such as extracorporeal membrane oxygenation (ECMO) and temporary support for right-sided failure, left-sided failure or biventricular failure. Most often, these devices are placed percutaneously and require either guidance with echocardiography, continuous radiography (fluoroscopy) or both. Furthermore, these devices need imaging in the intensive care unit to confirm continued accurate placement. This review contains the imaging views and nuances of the temporary assist devices (including ECMO) at the time of placement and the complications that can be associated with each individual device.

Prophylactic mechanical circulatory support for protected ventricular tachycardia ablation: A meta-analysis of the literature

Acute hemodynamic decompensation (AHD) during ventricular tachycardia (VT) ablation occurs in about 11% of cases. Prophylactic use of temporary mechanical circulatory support (pro-tMCS) has been applied to prevent AHD during VT ablation, but evidence supporting this practice is still lacking. This systematic review and meta-analysis assessed the procedural characteristics and outcomes of pro-tMCS for VT ablation. PubMed/Medline was screened until February 2020. Articles including adults receiving pro-tMCS for VT ablation were included, and a meta-analysis to compare proMCS and no-tMCS was performed. Primary outcome was in-hospital/30-day mortality. Five observational studies presenting 400 procedures (pro-tMCS: n = 187; no-tMCS: n = 213) were included. Baseline characteristics were comparable between groups. Impella and TandemHeart were used in 86.6% and 13.4% of cases, respectively. In the pro-tMCS group, more VTs were induced (mean difference: 0.52, confidence interval [CI]: 0.26-0.77, P < .0001), and patients remained in VT on average for 24.04 minutes longer (CI: 18.28-29.80, P < .00001). Procedural success was comparable between groups, as was VT recurrence. Pro-tMCS patients had an odds ratio of 0.55 (CI: 0.28-1.05, P = .07) for in-hospital/30-day mortality and 0.55 (CI: 0.32-0.94, P = .03) for mortality at follow-up. Sixty-four percent of no-tMCS patients received rescue tMCS. The most common tMCS-related complications were bleeding events. Pro-tMCS allowed for a prolonged time on VTs and the induction of more VTs. Although these advantages were not associated with differences in procedural success, VT recurrence, or in-hospital/30-day mortality in the overall population, pro-tMCS might improve long-term survival. Further prospective studies are urgently needed to confirm these results.

Left Ventricular Unloading With an IABP in Patients Undergoing Ventricular Tachycardia Ablation With ECMO Support

OBJECTIVE

The authors investigated the preprocedural predictors of postprocedural intra-aortic balloon pump (IABP) need in patients undergoing transcatheter ventricular tachycardia (VT) ablation on venoarterial (VA) extracorporeal membrane oxygenation (ECMO).

DESIGN

Observational study.

SETTING

Hybrid operating room and intensive care unit of a teaching hospital.

PATIENTS

Participants were 121 consecutive patients with unstable VT undergoing transcatheter ablation with VA-ECMO.

INTERVENTIONS

In patients with postprocedural echocardiographic, radiographic, or hemodynamic signs of increased left ventricle afterload, an IABP was positioned.

MEASUREMENTS AND MAIN RESULTS

Patients in the IABP group were more frequently on angiotensin-converting enzyme inhibitors (58% v 37%; p = 0.03) and had lower median baseline ejection fraction (25% v 28% p = 0.05), larger end-diastolic diameter (69.7 mm ± 13.0 v 65.7 mm ± 11.3; p = 0.03), and more frequent ischemic etiology as the reason for dilated cardiomyopathy (76% v 47%; p = 0.04,) when compared with patients not requiring IABP. Postoperatively, the IABP group required longer mechanical ventilation (24 hours [20-56.5] v 23 hours [15-28]; p = 0.003), intensive care unit stay (78 hours [46-174] v 48 hours [24-72]; p < 0.001), and continuous renal replacement therapy (13.3% v 1.3%; p = 0.006). By multivariate analysis, end-diastolic diameter (odds ratio [OR]:1.08; confidence interval [CI]: 1.00-1.16; p = 0.049), ischemic dilated cardiomyopathy (OR: 8.40; CI: 2.15-32.88; p = 0.002), and more-than-moderate mitral regurgitation (OR: 4.83; CI: 1.22-19.22; p = 0.025) were independent predictors of need for IABP.

CONCLUSIONS

The need for an IABP to unload the left ventricle can be predicted by ventricular size, medium-severe mitral valvular defect, and ischemic etiology of the dilated cardiomyopathy.

Influence of primary payer status on the management and outcomes of ST-segment elevation myocardial infarction in the United States

Background

There are limited contemporary data on the influence of primary payer status on the management and outcomes of ST-segment elevation myocardial infarction (STEMI).

Objective

To assess the influence of insurance status on STEMI outcomes.

Methods

Adult (>18 years) STEMI admissions were identified using the National Inpatient Sample database (2000–2017). Expected primary payer was classified into Medicare, Medicaid, private, uninsured and others. Outcomes of interest included in-hospital mortality, use of coronary angiography and percutaneous coronary intervention (PCI), hospitalization costs, hospital length of stay and discharge disposition.

Results

Of the 4,310,703 STEMI admissions, Medicare, Medicaid, private, uninsured and other insurances were noted in 49.0%, 6.3%, 34.4%, 7.2% and 3.1%, respectively. Compared to the others, the Medicare cohort was older (75 vs. 53–57 years), more often female (46% vs. 20–36%), of white race, and with higher comorbidity (all p<0.001). The Medicare and Medicaid population had higher rates of cardiogenic shock and cardiac arrest. The Medicare cohort had higher in-hospital mortality (14.2%) compared to the other groups (4.1–6.7%), p<0.001. In a multivariable analysis (Medicare referent), in-hospital mortality was higher in uninsured (adjusted odds ratio (aOR) 1.14 [95% confidence interval {CI} 1.11–1.16]), and lower in Medicaid (aOR 0.96 [95% CI 0.94–0.99]; p = 0.002), privately insured (aOR 0.73 [95% CI 0.72–0.75]) and other insurance (aOR 0.91 [95% CI 0.88–0.94]); all p<0.001. Coronary angiography (60% vs. 77–82%) and PCI (45% vs. 63–70%) were used less frequently in the Medicare population compared to others. The Medicare and Medicaid populations had longer lengths of hospital stay, and the Medicare population had the lowest hospitalization costs and fewer discharges to home.

Conclusions

Compared to other types of primary payers, STEMI admissions with Medicare insurance had lower use of coronary angiography and PCI, and higher in-hospital mortality.

Complications from percutaneous-left ventricular assist devices versus intra-aortic balloon pump in acute myocardial infarction-cardiogenic shock

BACKGROUND

There are limited data on the complications with a percutaneous left ventricular assist device (pLVAD) vs. intra-aortic balloon pump (IABP) in acute myocardial infarction-cardiogenic shock (AMI-CS).

OBJECTIVE

To assess the trends, rates and predictors of complications.

METHODS

Using a 17-year AMI-CS population from the National Inpatient Sample, AMI-CS admissions receiving pLVAD and IABP support were evaluated for vascular, lower limb amputation, hematologic, neurologic and acute kidney injury (AKI) complications. In-hospital mortality, hospitalization costs and length of stay in pLVAD and IABP cohorts with complications was studied.

RESULTS

Of 168,645 admissions, 7,855 (4.7%) receiving pLVAD support. The pLVAD cohort had higher comorbidity, cardiac arrest (36.1% vs. 29.7%) and non-cardiac organ failure (74.7% vs. 56.9%) rates. Complications were higher in pLVAD compared to IABP cohort-overall 69.0% vs. 54.7%; vascular 3.8% vs. 2.1%; lower limb amputation 0.3% vs. 0.3%; hematologic 36.0% vs. 27.7%; neurologic 4.9% vs. 3.5% and AKI 55.4% vs. 39.1% (all p<0.001 except for amputation). Non-White race, higher comorbidity, organ failure, and extracorporeal membrane oxygen use were predictors of complications for both cohorts. The pLVAD cohort with complications had higher in-hospital mortality (45.5% vs. 33.1%; adjusted odds ratio 1.65 [95% confidence interval 1.55-1.75]), shorter duration of hospital stay, and higher hospitalization costs compared to the IABP cohort with complications (all p<0.001). These results were consistent in propensity-matched pairs.

CONCLUSIONS

AMI-CS admissions receiving pLVAD had higher rates of complications compared to the IABP, with worse in-hospital outcomes in the cohort with complications.

Same-Day Versus Non-Simultaneous Extracorporeal Membrane Oxygenation Support for In-Hospital Cardiac Arrest Complicating Acute Myocardial Infarction

Background: Although extracorporeal membrane oxygenation (ECMO) is used for hemodynamic support for in-hospital cardiac arrest (IHCA) complicating acute myocardial infarction (AMI), there are limited data on the outcomes stratified by the timing of initiation of this strategy. Methods: Adult (>18 years) AMI admissions with IHCA were identified using the National Inpatient Sample (2000–2017) and the timing of ECMO with relation to IHCA was identified. Same-day vs. non-simultaneous ECMO support for IHCA were compared. Outcomes of interest included in-hospital mortality, temporal trends, hospitalization costs, and length of stay. Results: Of the 11.6 million AMI admissions, IHCA was noted in 1.5% with 914 (<0.01%) receiving ECMO support. The cohort receiving same-day ECMO (N = 795) was on average female, with lower comorbidity, higher rates of ST-segment-elevation AMI, shockable rhythm, and higher rates of complications. Compared to non-simultaneous ECMO, the same-day ECMO cohort had higher rates of coronary angiography (67.5% vs. 51.3%; p = 0.001) and comparable rates of percutaneous coronary intervention (58.9% vs. 63.9%; p = 0.32). The same-day ECMO cohort had higher in-hospital mortality (63.1% vs. 44.5%; adjusted odds ratio 3.98 (95% confidence interval 2.34–6.77); p < 0.001), shorter length of stay, and lower hospitalization costs. Older age, minority race, non-ST-segment elevation AMI, multiorgan failure, and complications independently predicted higher in-hospital mortality in IHCA complicating AMI. Conclusions: Same-day ECMO support for IHCA was associated with higher in-hospital mortality compared to those receiving non-simultaneous ECMO support. Though ECMO-assisted CPR is being increasingly used, careful candidate selection is key to improving outcomes in this population.

Influence of seasons on the management and outcomes acute myocardial infarction: An 18-year US study

Background

There are limited data on the seasonal variation in acute myocardial infarction (AMI) in the contemporary literature.

Hypothesis

There would be decrease in the seasonal variation in the management and outcomes of AMI.

Methods

Adult (>18 years) AMI admissions were identified using the National Inpatient Sample (2000‐2017). Seasons were classified as spring, summer, fall, and winter. Outcomes of interest included prevalence, in‐hospital mortality, use of coronary angiography, and percutaneous coronary intervention (PCI). Subgroup analyses for type of AMI and patient characteristics were performed.

Results

Of the 10 880 856 AMI admissions, 24.3%, 22.9%, 22.2%, and 24.2% were admitted in spring, summer, fall, and winter, respectively. The four cohorts had comparable age, sex, race, and comorbidities distribution. Rates of coronary angiography and PCI were slightly but significantly lower in winter (62.6% and 40.7%) in comparison to the other seasons (64‐65% and 42‐43%, respectively) (P < .001). Compared to spring, winter admissions had higher in‐hospital mortality (adjusted odds ratio [aOR]: 1.07; 95% confidence interval [CI]: 1.06‐1.08), whereas summer (aOR 0.97; 95% CI 0.96‐0.98) and fall (aOR 0.98; 95% CI 0.97‐0.99) had slightly lower in‐hospital mortality (P < .001). ST‐segment elevation (10.0% vs 9.1%; aOR 1.07; 95% CI 1.06‐1.08) and non‐ST‐segment elevation (4.7% vs 4.2%; aOR 1.07; 95% CI 1.06‐1.09) AMI admissions in winter had higher in‐hospital mortality compared to spring (P < .001). The primary results were consistent when stratified by age, sex, race, geographic region, and admission year.

Conclusions

Compared to other seasons, winter admission was associated with higher in‐hospital mortality in AMI in the United States.

Cardiogenic shock and cardiac arrest complicating ST-segment elevation myocardial infarction in the United States, 2000-2017

BACKGROUND

There are limited data on the outcomes of cardiogenic shock (CS) and cardiac arrest (CA) complicating ST-segment-elevation myocardial infarction (STEMI).

METHODS

Adult (>18 years) STEMI admissions were identified using the National Inpatient Sample (2000-2017) and classified as CS + CA, CS only, CA only and no CS/CA. Outcomes of interest included temporal trends, in-hospital mortality, hospitalization costs, use of do-not-resuscitate (DNR) status and palliative care referrals across the four cohorts.

RESULTS

Of the 4,320,117 STEMI admissions, CS, CA and both were noted in 5.8%, 6.2% and 2.7%, respectively. In 2017, compared to 2000, there was an increase in CA (adjusted odds ratio [aOR] 1.83 [95% confidence interval {CI} 1.79-1.86]), CS (aOR 3.92 [95% CI 3.84-4.01]) and both (aOR 4.09 [95% CI 3.94-4.24]) (all p < 0.001). The CS+CA (77.2%) cohort had higher rates of multiorgan failure than CS only (59.7%) and CA only (26.3%), p < 0.001. The CA only cohort had lower rates (64%) of coronary angiography compared to the other groups (>70%), p < 0.001. In-hospital mortality was higher in CS+CA compared to CS alone (adjusted OR 1.87 [95% CI 1.83-1.91]), CA alone (adjusted OR 1.99 [95% CI 1.95-2.03]) or neither (aOR 18.37 [95% CI 18.02-18.71]). The CS+CA cohort had higher use of palliative care and DNR status. The presence of CS, either alone or in combination with CA, was associated with higher hospitalization costs.

CONCLUSIONS

The combination of CS and CA was associated with higher rates of non-cardiac organ failure and in-hospital mortality in STEMI compared to those with either CS or CA alone.

Reporting of sex as a variable in cardiovascular studies using cultured cells: A systematic review

Reporting the sex of biological material is critical for transparency and reproducibility in science. This study examined the reporting of the sex of cells used in cardiovascular studies. Articles from 16 cardiovascular journals that publish peer-reviewed studies in cardiovascular physiology and pharmacology in the year 2018 were systematically reviewed using terms "cultured" and "cells." Data were collected on the sex of cells, the species from which the cells were isolated, and the type of cells, and summarized as a systematic review. Sex was reported in 88 (38.6%) of the 228 studies meeting inclusion criteria. Reporting rates varied with Circulation, Cardiovascular Research and American Journal of Physiology: Heart and Circulatory Physiology having the highest rates of sex reporting (>50%). A majority of the studies used cells from male (54.5%) or both male and female animals (32.9%). Humans (31.8%), rats (20.4%), and mice (43.8%) were the most common sources for cells. Cardiac myocytes were the most commonly used cell type (37.0%). Overall reporting of sex of experimental material remains below 50% and is inconsistent among journals. Sex chromosomes in cells have the potential to affect protein expression and molecular signaling pathways and should be consistently reported.

Burden of Arrhythmias in Acute Myocardial Infarction Complicated by Cardiogenic Shock

There are limited data on arrhythmias in acute myocardial infarction with cardiogenic shock (AMI-CS). Using a 17-year AMI-CS population from the National Inpatient Sample, we identified common arrhythmias - atrial fibrillation (AF), atrial flutter, supraventricular tachycardia, ventricular tachycardia, ventricular fibrillation, and atrioventricular blocks (AVB). Admissions with concomitant cardiac surgery were excluded. Outcomes of interest included temporal trends, predictors, in-hospital mortality, and resource utilization in cohorts with and without arrhythmias. Of the 420,319 admissions with AMI-CS during 2000 to 2016, arrhythmias were noted in 213,718 (51%). AF (45%), ventricular tachycardia (35%) and ventricular fibrillation (30%) were the most common arrhythmias. Compared with those without, the cohort w`ith arrhythmias was more often male, of white race, with ST-segment elevation AMI-CS presentation, and had higher rates of cardiac arrest and acute organ failure (all p <0.001). Temporal trends of prevalence revealed a stable trend of atrial and ventricular arrhythmias and declining trend in AVB. The cohort with arrhythmias had higher unadjusted (42% vs 41%; odds ratio [OR] 1.03 [95% confidence interval 1.02 to 1.05]; p <0.001), but not adjusted (OR 1.01 [95% CI 0.99 to 1.03]; p = 0.22) in-hospital mortality compared with those without. The cohort with arrhythmias had longer hospital stay (9 ± 10 vs 7 ± 9 days; p <0.001) and higher hospitalization costs ($124,000 ± 146,000 vs $91,000 ± 115,000; p <0.001). In the cohort with arrhythmias, older age, female sex, non-white race, higher co-morbidity, presence of acute organ failure, and cardiac arrest, predicted higher in-hospital mortality. In conclusion, cardiac arrhythmias in AMI-CS are a marker of higher illness severity and are associated with greater resource utilization.

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.

Complications in Patients with Acute Myocardial Infarction Supported with Extracorporeal Membrane Oxygenation

Background: There are limited data on complications in acute myocardial infarction (AMI) admissions receiving extracorporeal membrane oxygenation (ECMO). Methods: Adult (>18 years) admissions with AMI receiving ECMO support were identified from the National Inpatient Sample database between 2000 and 2016. Complications were classified as vascular, lower limb amputation, hematologic, and neurologic. Outcomes of interest included temporal trends, in-hospital mortality, hospitalization costs, and length of stay. Results: In this 17-year period, in ~10 million AMI admissions, ECMO support was used in 4608 admissions (<0.01%)—mean age 59.5 ± 11.0 years, 75.7% men, 58.9% white race. Median time to ECMO placement was 1 (interquartile range [IQR] 0–3) day. Complications were noted in 2571 (55.8%) admissions—vascular 6.1%, lower limb amputations 1.1%, hematologic 49.3%, and neurologic 9.9%. There was a steady increase in overall complications during the study period (21.1% in 2000 vs. 70.5% in 2016). The cohort with complications, compared to those without complications, had comparable adjusted in-hospital mortality (60.7% vs. 54.0%; adjusted odds ratio 0.89 [95% confidence interval 0.77–1.02]; p = 0.10) but longer median hospital stay (12 [IQR 5–24] vs. 7 [IQR 3–21] days), higher median hospitalization costs ($458,954 [IQR 260,522–737,871] vs. 302,255 [IQR 173,033–623,660]), fewer discharges to home (14.7% vs. 17.9%), and higher discharges to skilled nursing facilities (44.1% vs. 33.9%) (all p < 0.001). Conclusions: Over half of all AMI admissions receiving ECMO support develop one or more severe complications. Complications were associated with higher resource utilization during and after the index hospitalization.

Acute myocardial infarction-cardiogenic shock in patients with prior coronary artery bypass grafting: A 16-year national cohort analysis of temporal trends, management and outcomes

BACKGROUND

There are limited data on the outcomes of acute myocardial infarction with cardiogenic shock (AMI-CS) in patients with prior coronary artery bypass grafting (CABG).

METHODS

A retrospective cohort of AMI-CS admissions during 2000-2016 from the National Inpatient Sample was created and prior CABG status was identified. Outcomes of interest included in-hospital mortality and resource utilization in the two cohorts. Temporal trends of prevalence, in-hospital mortality, and cardiac procedures were evaluated.

RESULTS

In 513,288 AMI-CS admissions, prior CABG was performed in 22,832 (4.4%). Adjusted temporal trends showed a 2-fold increase in CS in both cohorts. There was a temporal increase in coronary angiography and percutaneous coronary intervention (PCI) across both cohorts. The cohort with prior CABG was on average older, of male sex, of white race, and with higher comorbidity. The cohort with prior CABG received coronary angiography (50% vs. 75%), PCI (32% vs. 49%), right heart catheterization/pulmonary artery catheterization (15% vs. 20%), mechanical circulatory support (26% vs. 46%) less frequently compared to those without (all p < 0.001). The cohort with CABG had higher in-hospital mortality (53% vs. 37%; adjusted odds ratio 1.41 [95% confidence interval 1.36-1.46]), greater use of do not resuscitate status (13% vs. 6%), shorter lengths of hospital stay (7 ± 8 vs. 10 ± 12 days), lower hospitalization costs ($92,346 ± 139,565 vs. 138,508 ± 172,895) and fewer discharges to home (39% vs. 43%) (all p < 0.001).

CONCLUSIONS

In AMI-CS, admission with prior CABG was older and had lower use of cardiac procedures and higher in-hospital mortality compared to those without prior CABG.