Causes of death and re‐hospitalization in 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.

Modes of Death in Patients with Cardiogenic Shock in the Cardiac Intensive Care Unit: A Report from the Critical Care Cardiology Trials Network

BACKGROUND

There are limited data on how patients with cardiogenic shock (CS) die.

METHODS

The Critical Care Cardiology Trials Network is a research network of cardiac intensive care units coordinated by the Thrombolysis In Myocardial Infarction (TIMI) Study Group (Boston, MA). Using standardized definitions, site investigators classified direct modes of in-hospital death for CS admissions (October 2021 to September 2022). Mutually exclusive categories included 4 modes of cardiovascular death and 4 modes of noncardiovascular death. Subgroups defined by CS type, preceding cardiac arrest (CA), use of temporary mechanical circulatory support (tMCS), and transition to comfort measures were evaluated.

RESULTS

Among 1068 CS cases, 337 (31.6%) died during the index hospitalization. Overall, the mode of death was cardiovascular in 82.2%. Persistent CS was the dominant specific mode of death (66.5%), followed by arrhythmia (12.8%), anoxic brain injury (6.2%), and respiratory failure (4.5%). Patients with preceding CA were more likely to die from anoxic brain injury (17.1% vs 0.9%; P < .001) or arrhythmia (21.6% vs 8.4%; P < .001). Patients managed with tMCS were more likely to die from persistent shock (P < .01), both cardiogenic (73.5% vs 62.0%) and noncardiogenic (6.1% vs 2.9%).

CONCLUSIONS

Most deaths in CS are related to direct cardiovascular causes, particularly persistent CS. However, there is important heterogeneity across subgroups defined by preceding CA and the use of tMCS.

Arrhythmic events and mortality in patients with cardiogenic shock on inotropic support: results of the DOREMI randomized trial

BACKGROUND

Inotropic support is widely used in the management of cardiogenic shock (CS). Existing data on the incidence and significance of arrhythmic events in patients with CS on inotropic support is at high risk of bias.

METHODS

The DObutamine compaREd to MIlrinone (DOREMI) trial randomized patients to receive dobutamine or milrinone in a double-blind fashion. Patients with and without arrhythmic events (defined as arrhythmias requiring intervention or sustained ventricular arrhythmias) were compared to (1) identify factors associated with their occurrence and (2) examine their association with in-hospital mortality and secondary outcomes.

RESULTS

Ninety-two patients (47.9%) had arrhythmic events, occurring equally with dobutamine and milrinone (P=0.563). The need for vasopressor support at inotrope initiation and a history of atrial fibrillation were positively associated with arrhythmic events whereas predominant right ventricular dysfunction, previous myocardial infarction, and increasing left ventricular ejection fraction were negatively associated with them. Supraventricular arrhythmic events were not associated with mortality (RR 0.97, 95% CI 0.68-1.40, P=0.879) but were positively associated with resuscitated cardiac arrests and hospital length of stay. Ventricular arrhythmic events were positively associated with mortality (RR 1.66, 95% CI 1.13-2.43; P=0.026) and resuscitated cardiac arrests. Arrhythmic events were most often treated with amiodarone (97%) and electrical cardioversion (27%), which were not associated with mortality.

CONCLUSIONS

Clinically relevant arrhythmic events occur in approximately half of patients with CS treated with dobutamine or milrinone and are associated with adverse clinical outcomes. Five factors may help identify patients most at risk of arrhythmic events.

Transradial versus transfemoral approach for percutaneous coronary intervention in patients with ST-elevation myocardial infarction complicated by cardiogenic shock: a systematic review and meta-analysis

BACKGROUND

In ST-elevation myocardial infarction (STEMI), transradial access (TRA) for percutaneous coronary intervention (PCI) is associated with less bleeding and mortality than transfemoral access (TFA). However, patients in cardiogenic shock (CS) are more often treated via TFA. The aim of this meta-analysis is to compare the safety and efficacy of TRA vs. TFA in CS.

METHODS

Systematic review was performed querying PubMed, Google Scholar, Cochrane, and clinicaltrials.gov for studies comparing TRA to TFA in PCI for CS. Outcomes included in-hospital, 30-day and ≥1-year mortality, major and access site bleeding, TIMI3 (thrombolytics in myocardial infarction) flow, procedural success, fluoroscopy time, and contrast volume. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated using random effects models.

RESULTS

Six prospective and eight retrospective studies (TRA, n = 8032; TFA, n = 23 031) were identified. TRA was associated with lower in-hospital (RR 0.59, 95% CI 0.52-0.66, P < 0.0001), 30-day and ≥1-year mortality, as well as less in-hospital major (RR 0.41, 0.31-0.56, P < 0.001) and access site bleeding (RR 0.42, 0.23-0.77, P = 0.005). There were no statistically significant differences in post-PCI coronary flow grade, procedural success, fluoroscopy time, and contrast volume between TRA vs. TFA.

CONCLUSIONS

In PCI for STEMI with CS, TRA is associated with significantly lower mortality and bleeding complications than TFA while achieving similar TIMI3 flow and procedural success rates.

Timing and Causes of Death in Acute Myocardial Infarction Complicated by Cardiogenic Shock (from the RETROSHOCK Cohort)

Acute myocardial infarction complicated by cardiogenic shock (AMICS) comprises a heterogeneous population with high mortality. Insight in timing and cause of death may improve understanding of the condition and aid individualization of treatment. This was assessed in a retrospective, multicenter observational cohort study based on 1,716 patients with AMICS treated during the period of 2010 to 2017, of whom 904 died before hospital discharge. Patients with AMICS were identified through national registries and review of individual patients charts. In 904 patients with AMICS who died before hospital discharge (median age 72 years [interquartile range (IQR) 63 to 79], 70% men), 342 (38%) had suffered out-of-hospital cardiac arrest. The most frequent cause of death was primary cardiac (54%), whereas 24% died of neurologic injury, and 20% of multiorgan failure (MOF). Time to death was 13 hours (IQR 5 to 43) for heart failure; 140 hours (IQR 95 to 209) in neurologic injury; and 137 hours (IQR 59 to 321) in MOF, p <0.001. The causes of death in patients presenting with out-of-hospital cardiac arrest (OHCA) were: neurologic injury in 57%, as opposed to 4% in patients not presenting with OHCA, p <0.001. In conclusion, in patients with AMICS, cause of death was mainly primary heart failure followed by neurologic injury and MOF. Median time from first medical contact to death was only 13 hours in patients dying from cardiac causes. The risk of dying of neurologic injury was low in patients without OHCA.

Incidence, Clinical Characteristics and Short-Term Prognosis in Patients With Cardiogenic Shock and Various Left Ventricular Ejection Fractions After Acute Myocardial Infarction

The 2016 European Society of Cardiology Guidelines introduced a new term, mid-range left ventricular ejection fraction (mrEF) heart failure, however, the clinical characteristics and short-term outcomes in cardiogenic shock patients with mrEF after acute myocardial infarction remain unclear. This retrospective study analyzed the baseline characteristics, management, and outcomes according to the left ventricular ejection fraction (LVEF), reduced LVEF (rEF) ≤40%, mrEF 41% to 49%, and preserved LVEF (pEF) ≥50% in patients with acute myocardial infarction complicated by cardiogenic shock. The primary end point was 30-day all-cause mortality and the secondary end point was the composite events of major adverse cardiovascular events (MACEs). In 218 patients, 71 (32.6%) were patients with mrEF. Compared with those with pEF, patients with mrEF had some similar clinical characteristics to that of rEF. The 30-day all-cause mortality in patients with rEF, mrEF, and pEF were 72.7%, 56.3%, and 32.0%, respectively (p = 0.001). The 30-day MACE were 90.9%, 69.0%, and 60.2%, respectively (p = 0.001). After multivariable adjustment, patients with mrEF and rEF had comparable 30-day all-cause mortality (hazard ratio [HR] = 0.81, 95% confidence interval [CI] 0.50 to 1.33, p = 0.404), and pEF was associated with decreased risk of 30-day all-cause mortality compared with rEF (HR = 0.41, 95% CI 0.24 to 0.71, p = 0.001). In contrast, the risk of 30-day MACE in mrEF and pEF were lower than that of rEF (HR = 0.62, 95% CI 0.40 to 0.96, p = 0.031 and HR = 0.53, 95% CI 0.34 to 0.80, p = 0.003, respectively). In conclusion, 1/3 of patients with acute myocardial infarction complicated by cardiogenic shock were mrEF. The clinical characteristics and short-term mortality in patients with mrEF were inclined to that of rEF and the occurrence of early left ventricular systolic dysfunction is of prognostic significance.

A Risk Stratification Scheme for In-Hospital Cardiogenic Shock in Patients With Acute Myocardial Infarction

Objective

Cardiogenic shock (CS) is the leading cause of death in patients with acute myocardial infarction (AMI) despite advances in care. This study aims to derive and validate a risk score for in-hospital development of CS in patients with AMI.

Methods

In this study, we used the Improving Care for Cardiovascular Disease in China–Acute Coronary Syndrome (CCC–ACS) registry of 76,807 patients for model development and internal validation. These patients came from 158 tertiary hospitals and 82 secondary hospitals between 2014 and 2019, presenting AMI without CS upon admission. The eligible patients with AMI were randomly assigned to derivation (n = 53,790) and internal validation (n = 23,017) cohorts. Another cohort of 2,205 patients with AMI between 2014 and 2016 was used for external validation. Based on the identified predictors for in-hospital CS, a new point-based CS risk scheme, referred to as the CCC–ACS CS score, was developed and validated.

Results

A total of 866 (1.1%) and 39 (1.8%) patients subsequently developed in-hospital CS in the CCC–ACS project and external validation cohort, respectively. The CCC–ACS CS score consists of seven variables, including age, acute heart failure upon admission, systolic blood pressure upon admission, heart rate, initial serum creatine kinase-MB level, estimated glomerular filtration rate, and mechanical complications. The area under the curve for in-hospital development of CS was 0.73, 0.71, and 0.85 in the derivation, internal validation and external validation cohorts, respectively.

Conclusion

This newly developed CCC–ACS CS score can quantify the risk of in-hospital CS for patients with AMI, which may help in clinical decision making.

Clinical Trial Registration

www.ClinicalTrials.gov, identifier: NCT02306616.

Prognostic value of depressed cardiac index after STEMI: a phase-contrast magnetic resonance study

AIMS 

An invasively measured cardiac index (CI) of ≤2.2 L/min/m2 is one of the strongest prognostic indicators after ST-elevation myocardial infarction (STEMI), however, knowledge is mainly based on invasive evaluations performed in the pre-stent era. Velocity-encoded phase-contrast cardiac magnetic resonance (PC-CMR) allows non-invasive determination of CI.

METHODS AND RESULTS 

In this prospective study, CMR was performed in 406 stable and contemporarily revascularized patients a median of 3 days after STEMI. Forward stroke volume was assessed at the level of the ascending aorta by PC-CMR. Left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) were determined by cine CMR. Major adverse cardiac events (MACE) were defined as the composite of death, myocardial infarction, or hospitalization for heart failure. Median CI was 2.52 L/min/m2 and 27% of patients had ≤2.2 L/min/m2. Median LVEF was 53% and median GLS was -12.2%. During a median follow-up of 14.2 [95% confidence interval (95% CI) 13.6-14.7] months, 41 patients (10.1%) experienced a MACE. A depressed CI was significantly associated with MACE after adjustment for LVEF, GLS, Thrombolysis in Myocardial Infarction (TIMI) risk score, and infarct size [hazard ratio = 3.15 (95% CI 1.53-6.47); P = 0.002] and led to significant discrimination improvement [net reclassification improvement 0.61 (95% CI 0.25-0.97); P < 0.001].

CONCLUSIONS 

A CI of 2.2 L/min/m2 or less as measured by PC-CMR was present in 27% of clinically stable patients after STEMI and strongly and independently predicted medium-term MACE. The prognostic value of a depressed CI was superior and incremental to LVEF, GLS, TIMI risk score, and infarct size.

Use of Post-Acute Care Services and Readmissions After Acute Myocardial Infarction Complicated by Cardiac Arrest and Cardiogenic Shock

OBJECTIVE

To evaluate post-acute care utilization and readmissions after cardiac arrest (CA) and cardiogenic shock (CS) complicating acute myocardial infarction (AMI).

METHODS

With use of an administrative claims database, AMI patients from January 1, 2010, to May 31, 2018, were stratified into CA+CS, CA only, CS only, and AMI alone. Outcomes included 90-day post-acute care (inpatient rehabilitation or skilled nursing facility) utilization and 1-year emergency department visits and readmissions.

RESULTS

Of 163,071 AMI patients, CA+CS, CA only, and CS only were noted in 3965 (2.4%), 8221 (5.0%), and 6559 (4.0%), respectively. In-hospital mortality was noted in 10,686 (6.6%) patients: CA+CS, 1935 (48.8%); CA only, 2948 (35.9%); CS only, 1578 (24.1%); and AMI alone, 4225 (2.9%) (P<.001). Among survivors, post-acute care services were used in 67,799 (44.5%), with higher use in the CS+CA cohort (1310 [64.6%]; hazard ratio [HR], 1.19; 95% CI, 1.06 to 1.33; P=.003) and CA cohort (2738 [51.9%]; HR, 1.27; 95% CI, 1.20 to 1.35; P<.001) but not in the CS cohort (3048 [61.2%]; HR, 1.03; 95% CI, 0.97 to 1.11; P=.35) compared with the AMI cohort (60,703 [43.3%]). Compared with the AMI cohort (48,990 [35.0%]), patients with CS only (2,085 [41.9%]; HR, 1.16; 95% CI, 1.10 to 1.22; P<.001) but not those with CA+CS (724 [35.7%]; HR, 1.07; 95% CI, 0.98 to 1.17; P=.14) had higher rates of readmissions (P=.03). Readmissions were lower in those with CA (1,590 [30.2%]; HR, 0.94; 95% CI, 0.89 to 0.99). Repeated AMI, coronary artery disease, and heart failure were the most common readmission reasons. There were no differences for emergency department visits.

CONCLUSION

CA is associated with increased post-acute care use, whereas CS is associated with increased readmission risk in AMI survivors.

Early intra-aortic balloon pump in acute decompensated heart failure complicated by cardiogenic shock: Rationale and design of the randomized Altshock-2 trial

BACKGROUND

Cardiogenic shock (CS) is a systemic disorder associated with dismal short-term prognosis. Given its time-dependent nature, mechanical circulatory support may improve survival. Intra-aortic balloon pump (IABP) had gained widespread use because of the easiness to implant and the low rate of complications; however, a randomized trial failed to demonstrate benefit on mortality in the setting of acute myocardial infarction. Acute decompensated heart failure with cardiogenic shock (ADHF-CS) represents a growing resource-intensive scenario with scant data and indications on the best management. However, a few data suggest a potential benefit of IABP in this setting. We present the design of a study aimed at addressing this research gap.

METHODS AND DESIGN

The Altshock-2 trial is a prospective, randomized, multicenter, open-label study with blinded adjudicated evaluation of outcomes. Patients with ADHF-CS will be randomized to early IABP implantation or to vasoactive treatments. The primary end point will be 60 days patients' survival or successful bridge to heart replacement therapy. The key secondary end point will be 60-day overall survival; 60-day need for renal replacement therapy; in-hospital maximum inotropic score, maximum duration of inotropic/vasopressor therapy, and maximum sequential organ failure assessment score. Safety end points will be in-hospital occurrence of bleeding events (Bleeding Academic Research Consortium >3), vascular access complications and systemic (noncerebral) embolism. The sample size for the study is 200 patients.

IMPLICATIONS

The Altshock-2 trial will provide evidence on whether IABP should be implanted early in ADHF-CS patients to improve their clinical outcomes.

Veno-arterial extracorporeal membrane oxygenation (ECMO) in patients with cardiogenic shock: rationale and design of the randomised, multicentre, open-label EURO SHOCK trial

AIMS

Cardiogenic shock (CGS) occurs in 6-10% of patients with acute coronary syndromes (ACS). Mortality has fallen over time from 80% to approximately 50% consequent on acute revascularisation but has plateaued since the 1990s. Once established, patients with CGS develop adverse compensatory mechanisms that contribute to the downward spiral towards death, which becomes difficult to reverse. We aimed to test in a robust, prospective, randomised controlled trial whether early support with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) provides clinical benefit by improving mortality and morbidity.

METHODS AND RESULTS

The EURO SHOCK trial will test the benefit or otherwise of mechanical cardiac support using VA-ECMO, initiated early after acute percutaneous coronary intervention (PCI) for CGS. The trial sets out to randomise 428 patients with CGS complicating ACS, following primary PCI (P-PCI), to either very early ECMO plus standard pharmacotherapy, or standard pharmacotherapy alone. It will be conducted in 39 European centres. The primary endpoint is 30-day all-cause mortality with key secondary endpoints: 1) 12-month all-cause mortality or admission for heart failure, 2) 12-month all-cause mortality, 3) 12-month admission for heart failure. Cost-effectiveness analysis (including quality of life measures) will be embedded. Mechanistic and hypothesis-generating substudies will be undertaken.

CONCLUSIONS

The EURO SHOCK trial will determine whether early initiation of VA-ECMO in patients presenting with ACS-CGS persisting after PCI improves mortality and morbidity.

Percutaneous Left Ventricular Assist Device Leads to Heart Rhythm Stabilisation in Cardiogenic Shock: Results from the Dresden Impella Registry

BACKGROUND

Severe heart rhythm disturbances (SHRDs) occur regularly in cardiogenic shock (CS). Percutaneous left ventricular assist devices (pLVADs) can actively unload the left ventricle (LV), decreasing left ventricular end-diastolic pressure and wall tension, which are suspected parameters for the induction and maintenance of arrhythmias. The aim of this study was to describe effects of LV unloading on SHRD.

METHOD

In the Dresden Impella Registry, 97 patients received an Impella CP in refractory CS. Of them, 19 had SHRDs, which were not stopped by common therapeutic strategies such as electrical defibrillation or antiarrhythmic drugs. They were only stopped after implantation of a micro-axial heart pump. This phenomenon was referred to as heart rhythm stabilisation (HRS). Clinical outcome and laboratory parameters were assessed and risk factors for the occurrence of HRS were identified.

RESULTS

All 19 patients with refractory SHRD terminated immediately into a stable heart rhythm after insertion of the micro-axial heart pump. In 37% no additional defibrillation was needed. Of the patients with HRS, CS was mostly caused by myocardial infarction (68%). Resuscitation before pLVAD was performed in 89% for more than 30 minutes. Patients with HRS were resuscitated more frequently and for a longer duration than patients without HRS. After HRS, the serum lactate and norepinephrine dosage decreased in the first 12 hours, whereas left ventricular ejection fraction increased by 95%.

CONCLUSIONS

Left ventricular unloading in patients with CS seems to be an option for treating patients with sustained life-threatening tachycardia, who are refractory to common treatment.

Incidence and clinical outcomes of nosocomial infections in patients presenting with STEMI complicated by cardiogenic shock in the United States

OBJECTIVES

This study addresses the incidence, trends, and impact of nosocomial infections (NI) on the outcomes of patients admitted with ST-segment elevation myocardial infarction (STEMI) and cardiogenic shock (STEMI-CS) using the United States National Inpatient Sample (NIS) database.

METHODS

We analyzed data from 105,184 STEMI-CS patients using the NIS database from the years 2005-2014. NI was defined as infections of more than or equal to three days, comprising of central line-associated bloodstream infection (CLABSI), urinary tract infection (UTI), hospital-acquired pneumonia (HAP), Clostridium difficile infection (CDI), bacteremia, and skin related infections. Outcomes of the impact of NI on STEMI-CS included in-hospital mortality, length of hospital stay (LOS) and costs. Significant associations of NI in patients admitted with STEMI-CS were also identified.

RESULTS

Overall, 19.1% (20,137) of patients admitted with STEMI-CS developed NI. Trends of NI have decreased from 2005-2014. The most common NI were UTI (9.2%), followed by HAP (6.8%), CLABSI (1.5%), bacteremia (1.5%), skin related infections (1.5%), and CDI (1.3%). The strongest association of developing a NI was increasing LOS (7-9 days; OR: 1.99; 95% CI: 1.75-2.26; >9 days; OR: 4.51; 95% CI: 4.04-5.04 compared to 4-6 days as reference). Increased mortality risk among patients with NI was significant, especially those with sepsis-associated NI compared to those without sepsis (OR: 2.95; 95% CI: 2.72-3.20). Patients with NI were found to be associated with significantly longer LOS and higher costs, irrespective of percutaneous mechanical circulatory support placement.

CONCLUSIONS

NI were common among patients with STEMI-CS. Those who developed NI were at a greater risk of in-hospital mortality, increased LOS and costs.

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.

Frequency of 30-day readmission and its causes after percutaneous coronary intervention in acute myocardial infarction complicated by cardiogenic shock

BACKGROUND

Survival after percutaneous coronary intervention (PCI) in acute myocardial infarction complicated by cardiogenic shock (AMI-CS) has increased over the years. Short-term readmission rates in this high-risk population remain unknown.

METHODS

We queried the United States (U.S.) Nationwide Readmission Database (NRD) from January 2010 to November 2014 using the International Classification of Diseases-Ninth edition, Clinical Modification (ICD-9 CM) codes to identify all patients ≥18 years readmitted within 30 days after surviving an index hospitalization for PCI in AMI-CS. Incidence, etiologies, and predictors of 30-day readmission were analyzed.

RESULTS

Among 46,435 patients who survived to discharge after PCI in AMI-CS, 9,020 (19.4%) were readmitted within 30 days. Median time to 30-day readmission was 11 days. Cardiac conditions were the most common causes of readmission (57.8%). Heart failure was the leading readmission diagnosis (24.8%). Private insurance including HMO and self-pay were predictive of lower 30-day readmission. Among other covariates, female sex, comorbidities such as heart failure, atrial fibrillation, in-hospital complications such as major bleeding, sepsis, respiratory complications, AKI requiring dialysis, utilization of mechanical circulatory support (IABP and ECMO) were independently predictive of 30-day readmission. Trend analysis showed decline in 30-day readmission rates from 21.9% in 2010 to 17.9% in 2014 (p_trend  < 0.001).

CONCLUSION

In this large real-world database, one in five patients receiving PCI in AMI-CS was readmitted within 30 days after discharge. Cardiac conditions were the most common causes of readmission. Insurance type had significant influence on 30-day readmission.

Development and Testing of a Novel Anaesthesia Induction/Ventilation Protocol for Patients With Cardiogenic Shock Complicating Acute Myocardial Infarction

BACKGROUND

Cardiogenic shock is a life-threatening condition and patients might require rapid sequence induction (RSI) and mechanical ventilation. In this study, we evaluated a new RSI/mechanical ventilation protocol in patients with acute myocardial infarction complicated by cardiogenic shock.

METHODS

We included consecutive adult patients who were transferred to the emergency department. The RSI protocol included 5 phases: preoxygenation, pretreatment, induction/paralysis, intubation, and mechanical ventilation (PPIIM). A posteriori, we selected historical patients managed with standard RSI as a control group. The primary outcome was hemodynamic derangement or hypoxemia from enrollment until intensive care unit (ICU) admission.

RESULTS

We studied 31 consecutive patients who were intubated using the PPIIM protocol and 22 historical controls. We found significant differences in systolic (85.32 ± 4.23 vs 71.72 ± 7.98 mm Hg; P < 0.0001), diastolic (58.84 ± 5.84 vs 39.05 ± 5.63 mm Hg; P < 0.0001), and mean arterial pressure (67.71 ± 4.90 vs 49.90 ± 5.66 mm Hg; P < 0.0001), as well as in partial pressure of oxygen (85.80 ± 19.82 vs 164.73 ± 43.07 mm Hg; P < 0.0001) between the PPIIM and control group at 5 minutes of automated ventilation. Also, statistically significant differences were observed in diastolic (59.74 ± 4.93 vs 47.86 ± 11.47 mm Hg; P < 0.0001) and mean arterial pressure (68.65 ± 4.10 vs 60.23 ± 11.67 mm Hg; P < 0.0001), as well as in partial pressure of oxygen (119.84 ± 50.57 vs 179.50 ± 42.17 mm Hg; P < 0.0001), and partial pressure of carbon dioxide (39.81 ± 10.60 vs 31.00 ± 9.30 mm Hg; P = 0.003) between the 2 groups at ICU admission. Compared with the control group, with PPIIM more patients survived to ICU admission (100% vs 77%) and hospital discharge (71% vs 31.8%), as well as at 90 days (51.6% vs 18.2%), and at 180 days (38.7% vs 13.6%).

CONCLUSIONS

The PPIIM protocol allows safe intubation of acute myocardial infarction patients with cardiogenic shock and improves hemodynamic and oxygenation parameters.

Causes and Predictors of 30-Day Readmission in Patients With Acute Myocardial Infarction and Cardiogenic Shock

Background:

Acute myocardial infarction (AMI) occurs as a result of irreversible damage to cardiac myocytes secondary to lack of blood supply. Cardiogenic shock complicating AMI has significant associated morbidity and mortality, and data on postdischarge outcomes are limited.

Methods and Results:

We derived the study cohort of patients with AMI and cardiogenic shock from the 2013 to 2014 Healthcare Cost and Utilization Project National Readmission Database. Incidence, predictors, and causes of 30-day readmissions were analyzed. From 43 212 index admissions for AMI with cardiogenic shock, 26 016 (60.2%) survived to discharge and 5277 (20.2% of survivors) patients were readmitted within 30 days. More than 50% of these readmissions occurred within first 10 days. Cardiac causes accounted for 42% of 30-day readmissions (heart failure 20.6%; acute coronary syndrome 11.6%). Among noncardiac causes, respiratory (11.4%), infectious (9.4%), medical or surgical care complications (6.3%), gastrointestinal/hepatobiliary (6.5%), and renal causes (4.8%) were most common. Length of stay ≥8 days (odds ratio [OR], 2.04; 95% confidence interval [CI], 1.70–2.44; P <0.01), acute deep venous thrombosis (OR, 1.26; 95% CI, 1.08–1.48; P <0.01), liver disease (OR, 1.25; 95% CI, 1.03–1.50; P =0.02), systemic thromboembolism (OR, 1.21; 95% CI, 1.02–1.44; P =0.02), peripheral vascular disease (OR, 1.16; 95% CI, 1.07–1.27; P <0.01), diabetes mellitus (OR, 1.16; 95% CI, 1.08–1.24; P <0.01), long-term ventricular assist device implantation (OR, 1.77; 95% CI, 1.23–2.55; P <0.01), intraaortic balloon pump use (OR, 1.10; 95% CI, 1.02–1.18; P <0.01), performance of coronary artery bypass grafting (OR, 0.85; 95% CI, 0.77–0.93; P <0.01), private insurance (OR, 0.72; 95% CI, 0.64–0.80; P <0.01), and discharge to home (OR, 0.85; 95% CI, 0.73–0.98; P =0.03) were among the independent predictors of 30-day readmission.

Conclusions:

In-hospital mortality and 30-day readmission in cardiogenic shock complicating AMI are significantly elevated. Patients are readmitted mainly for noncardiac causes. Identification of high-risk factors may guide interventions to improve outcomes within this population.

Efficacy of cardiac resynchronization in acutely infarcted canine hearts with electromechanical dyssynchrony

BACKGROUND

Patients with acute myocardial infarction (MI), left bundle branch block (LBBB), and marked left ventricular (LV) decompensation suffer from nearly 50% early mortality. Whether cardiac resynchronization therapy (CRT) improves hemodynamic status in this condition is unknown. We tested CRT in this setting by using a canine model of delayed lateral wall (LW) activation combined with 2 hours of coronary artery occlusion-reperfusion.

OBJECTIVE

This study aimed to evaluate the acute hemodynamic effects of CRT during and immediately after MI.

METHODS

Adult dogs (n = 8) underwent open-chest 2-hour mid-left anterior descending artery occlusion followed by 1-hour reperfusion. Four pacing modes were compared: right atrial pacing, pseudo-left bundle block (right ventricular pacing), and CRT with the LV lead positioned at either the LW (LW-CRT) or the peri-infarct zone (peri-infarct zone-CRT). Continuous LV pressure-volume data, regional segment length, and proximal left anterior descending flow rates were recorded.

RESULTS

At baseline, both right ventricular pacing and peri-infarct zone CRT reduced anterior wall regional work by ~50% (vs right atrial pacing). During coronary occlusion, this territory became dyskinetic, and dyskinesis rose further with both CRT modes as compared to pseudo-LBBB. Global cardiac output, stroke work, and ejection fraction all still improved by 11%-23%. After reperfusion, both CRT modes elevated infarct zone regional work and blood flow by ~10% as compared to pseudo-LBBB, as well as improved global function.

CONCLUSION

CRT improves global chamber systolic function in left ventricles with delayed LW activation during and after sustained coronary occlusion. It does so while modestly augmenting infarct zone dyskinesis during occlusion and improving regional function and blood flow after reperfusion. These findings support CRT in the setting of early post-MI dyssynchronous heart failure.

Arterial access site utilization in cardiogenic shock in the United Kingdom: is radial access feasible?

BACKGROUND

Cardiogenic shock (CS) remains the leading cause of mortality in patients hospitalized with acute myocardial infarction (AMI). The transradial access site (TRA) has become increasingly adopted as a default access site for percutaneous coronary intervention (PCI); however, even in experienced centers that favor the radial artery as the primary access site during PCI, patients presenting in CS are often treated via the transfemoral access site (TFA); and commentators have suggested that CS remains the final frontier that has given even experienced radial operators pause. We studied the use of TRA in patients presenting in CS in a nonselected high-risk cohort from the British Cardiovascular Intervention database over a 7-year period (2006-2012).

METHODS

Mortality (30-day) and major adverse cardiac and cerebrovascular events (a composite of in-hospital mortality, in-hospital myocardial reinfarction, target vessel revascularization, and cerebrovascular events) were studied based on TFA and TRA utilization in CS patients. The influence of access site selection was studied in 7,231 CS patients; TFA was used in 5,354 and TRA in 1,877 patients.

RESULTS

Transradial access site was independently associated with a lower 30-day mortality (hazard ratio [HR] 0.56, 95% CI 0.46-0.69, P = 0 < .001), in-hospital major adverse cardiac and cerebrovascular events (HR 0.64, 95% CI 0.53-0.76, P < .0001) and major bleeding (HR 0.37, 95% CI 0.18-0.73, P = .004).

CONCLUSIONS

Although the majority of PCI cases performed in patients with cardiogenic shock in the United Kingdom are performed through the TFA, the radial artery represents an alternative viable access site in this high-risk cohort of patients in experienced centers.

Long-term outcomes among older patients with non-ST-segment elevation myocardial infarction complicated by cardiogenic shock

BACKGROUND

Cardiogenic shock complicating acute myocardial infarction (MI) in older patients is associated with a high risk of inhospital mortality; however, the long-term prognosis among these patients who survive the index hospitalization is uncertain.

METHODS

We evaluated 42,656 patients 65 years or older with non-ST-segment elevation MI from the CRUSADE Registry treated at 448 hospitals in the United States from 2003 to 2006 and linked to Medicare longitudinal claims data. Among patients who survived to hospital discharge, Cox proportional hazards modeling was used to compare survival between patients with and without inhospital shock. The secondary outcome of "percent days alive and out of hospital" (%DAOH) was also compared between the 2 groups.

RESULTS

Overall, 2,001 (4.7%) patients had shock on presentation and/or developed shock during the index hospitalization. Inhospital mortality rates among those with and without shock were 39.1% versus 4.5% (P < .001). Among the 40,036 index hospital survivors, postdischarge survival curves diverged early with lower survival (48.1% [95% CI 45.0-51.2] vs 56.5% [95% CI 56.0-57.1], P < .001) and lower %DAOH (65.5% ± 40.6% and 73.4% ± 36.8 %, P < .001) among patients with shock through 4 years. Based on the observation of parallel survival curves starting 6 months postdischarge, we performed landmark analyses and found no difference in mortality (hazard ratio 1.02, 95% CI 0.91-1.14) or %DAOH (79.7% ± 32.0% vs 81.3% ± 31.0%, P = .17) beyond 6 months between those with and without shock.

CONCLUSIONS

Our results highlight the time-dependent hazard of risk during the early postdischarge period for older patients with non-ST-segment elevation MI and cardiogenic shock that appears to be mitigated after 6 months, thereby lending support for the examination of new therapies designed to ameliorate this early risk.

Serious infection after acute myocardial infarction: incidence, clinical features, and outcomes

OBJECTIVES

The aim of this study was to address the knowledge gap using the APEX-AMI (Assessment of Pexelizumab in Acute Myocardial Infarction) trial database. We also assessed the association between serious infections and 90-day death or death/myocardial infarction (MI).

BACKGROUND

Little is known about the incidence, location, etiological organisms, and outcomes of infection in patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention.

METHODS

We analyzed data from 5,745 STEMI patients enrolled in the APEX-AMI trial. Detailed information on infection was collected for all patients. We described characteristics of patients according to infection and details of infection. Cox proportional hazards models were used to assess 90-day outcomes among patients with and without infections after adjusting for associated clinical variables and with infection as a time-dependent covariate.

RESULTS

Overall, 138 patients developed a serious infection (2.4%), most of whom presented with a single-site infection. The median (25th, 75th percentile) time until diagnosis of infection was 3 (1, 6) days. The most commonly identified organism was Staphylococcus aureus, and the main location of infection was the bloodstream. These patients had more comorbidities and lower procedural success at index percutaneous coronary intervention than those without infections. Serious infection was associated with significantly higher rates of 90-day death (adjusted hazard ratio: 5.6; 95% confidence interval: 3.8 to 8.4) and death or MI (adjusted hazard ratio: 4.9; 95% confidence interval: 3.4 to 7.1).

CONCLUSIONS

Infections complicating the course of patients with STEMI were uncommon but associated with markedly worse 90-day clinical outcomes. Mechanisms for early identification of these high-risk patients as well as design of strategies to reduce their risk of infection are warranted.