Intra-aortic Balloon Pump Therapy for Acute Myocardial Infarction: A Meta-analysis

ECMO versus IABP for patients with STEMI complicated by cardiogenic shock undergoing primary PCI: a Chinese National Study and propensity-matched analysis

OBJECTIVE

This study investigated the association between the utilization of extracorporeal membrane oxygenation (ECMO) or intra-aortic balloon pump (IABP) and in-hospital mortality among patients with ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock undergoing primary percutaneous coronary intervention (PCI).

METHODS

Data encompassing 9635 cases of STEMI complicated by cardiogenic shock and treated with primary PCI using ECMO/IABP support were retrieved from the Chinese Cardiovascular Association database (2019-2021). We conducted an analysis to assess the in-hospital survival disparities among percutaneous mechanical circulatory device recipients and explore the potential advantages of ECMO through multivariable logistic regression analysis within a propensity score-matched (1:2) cohort population.

RESULTS

ECMO was administered to 2028 patients, whereas IABP was used in 7607 patients. Patients supported by ECMO showed a lower in-hospital mortality than those supported by IABP (7.2% versus 15.1%, p < 0.001). Within the propensity-matched (case: control = 1:2) cohort, we noted a 34% reduced risk of in-hospital mortality among patients supported by ECMO compared with those supported by IABP (7.7% versus 11.7%; odds ratio = 0.66; 95% CI, 0.53-0.80; p < 0.001) independent of age, sex, systolic blood pressure, obesity, smoke, hypertension, diabetes, dyslipidemia, family history of coronary artery disease, coronary artery disease, stroke, atrial filiation, peripheral artery disease, chronic kidney disease, vascular lesion sites, 3A-grade hospital, and regional distributions in China.

CONCLUSION

Among patients undergoing primary PCI for STEMI complicated by cardiogenic shock, ECMO was associated with better in-hospital survival than IABP.

Haemodynamic support with percutaneous devices in patients with cardiogenic shock: the current evidence of mechanical circulatory support

INTRODUCTION

Cardiogenic shock (CS) is a complex life-threatening condition that results from primary cardiac dysfunction, leading to persistent hypotension and systemic hypoperfusion. Among the therapeutic options for CS are various percutaneous mechanical circulatory support (MCS) devices that have emerged as an increasingly effective hemodynamic support option. Percutaneous therapies can act as short-term mechanical circulatory assistance and can be split into intra-aortic balloon pump (IABP) and non-IABP percutaneous mechanical devices.

AREAS COVERED

This review will evaluate the MCS value while considering the mortality rate improvements. We also aim to outline the function of pharmacotherapies and percutaneous hemodynamic MCS devices in managing CS patients to avoid the onset of end-organ dysfunction and improve both early and late outcomes.

EXPERT OPINION

Given the complexity, acuity and high mortality associated with CS, and despite the availability and efficacy of pharmacological management, MCS is required to achieve hemodynamic stability and improve survival. Various percutaneous MCS devices are available with varying indications and clinical outcomes. The rates of early mortality and complications were found to be comparable between the four devices, yet, IABP seemed to show the most optimal clinical profile whilst ECMO demonstrated its more long-term efficacy.

Volume-Outcome Relationships for Intra-Aortic Balloon Pump in Acute Myocardial Infarction

BACKGROUND

Acute myocardial infarction (AMI) is a major scenario for the use of an intra-aortic balloon pump (IABP), particularly when complicated by cardiogenic shock, although the utilization of mechanical circulatory support devices varies widely per hospital. We evaluated the relationship, at the hospital level, between the volume of IABP use and mortality in AMI.

METHODS AND RESULTS

Using a Japanese nationwide administrative database, 26,490 patients with AMI undergoing primary percutaneous coronary intervention (PCI) from 154 hospitals were included in this study. The primary endpoint was the observed-to-predicted in-hospital mortality ratio. Predicted mortality per patient was calculated using baseline variables and averaged for each hospital. The associations among PCI volume for AMI, observed and predicted in-hospital mortality, and observed and predicted IABP use were assessed per hospital. Of 26,490 patients, 2,959 (11.2%) were treated with IABP and 1,283 (4.8%) died during hospitalization. The annualized number of uses of IABP per hospital in AMI was 4.5. In lower-volume primary PCI centers, IABP was more likely to be underused than expected, and the observed-to-predicted in-hospital mortality ratio was higher than in higher-volume centers.

CONCLUSIONS

A lower annual number of IABP use was associated with an increased mortality risk at the hospital level, suggesting that IABP use can be an institutional quality indicator in the setting of AMI.

Acute myocardial infarction complicated by cardiogenic shock in Ukraine: multicentre registry analysis 2021-2022

Background

Data on the results and management strategies in patients with acute myocardial infarction complicated by cardiogenic shock (AMI-CS) in the Low and Lower-Middle Income Countries (LLMICs) are limited. This lack of understanding of the situation partially hinders the development of effective cardiogenic shock treatment programs in this part of the world.

Materials and methods

The Ukrainian Multicentre Cardiogenic Shock Registry was analyzed, covering patient data from 2021 to 2022 in 6 major Ukrainian reperfusion centres from different parts of the country. Analysis was focusing on outcomes, therapeutic modalities and mortality predictors in AMI-CS patients.

Results

We analyzed data from 221 consecutive patients with CS from 6 hospitals across Ukraine. The causes of CS were ST-elevated myocardial infarction (85.1%), non-ST-elevated myocardial infarction (5.9%), decompensated chronic heart failure (7.7%) and arrhythmia (1.3%), with a total in-hospital mortality rate for CS of 57.1%. The prevalence of CS was 6.3% of all AMI with reperfusion rate of 90.5% for AMI-CS. In 23.5% of cases, CS developed in the hospital after admission. Mechanical circulatory support (MCS) utilization was 19.9% using intra-aortic balloon pump alone. Left main stem occlusion, reperfusion deterioration, Charlson Comorbidity Index >4, and cardiac arrest were found to be independent predictors for hospital mortality in AMI-СS.

Conclusions

Despite the wide adoption of primary percutaneous coronary intervention as the main reperfusion strategy for AMI, СS remains a significant problem in LLMICs, associated with high in-hospital mortality. There is an unmet need for the development and implementation of a nationwide protocol for CS management and the creation of reference CS centers based on the country-wide reperfusion network, equipped with modern technologies for MCS.

Mechanical circulatory support for cardiogenic shock: a network meta-analysis of randomized controlled trials and propensity score-matched studies

PURPOSE

Cardiogenic shock is associated with high mortality. In refractory shock, it is unclear if mechanical circulatory support (MCS) devices improve survival. We conducted a network meta-analysis to determine which MCS devices confers greatest benefit.

METHODS

We searched MEDLINE, Embase, and Scopus databases through 27 August 2023 for relevant randomized controlled trials (RCTs) and propensity score-matched studies (PSMs). We conducted frequentist network meta-analysis, investigating mortality (either 30 days or in-hospital) as the primary outcome. We assessed risk of bias (Cochrane risk of bias 2.0 tool/Newcastle-Ottawa Scale) and as sensitivity analysis reconstructed survival data from published survival curves for a one-stage unadjusted individual patient data (IPD) meta-analysis using a stratified Cox model.

RESULTS

We included 38 studies (48,749 patients), mostly reporting on patients with Society for Cardiovascular Angiography and Intervention shock stages C-E cardiogenic shock. Compared with no MCS, extracorporeal membrane oxygenation with intra-aortic balloon pump (ECMO-IABP; network odds ratio [OR]: 0.54, 95% confidence interval (CI): 0.33-0.86, moderate certainty) was associated with lower mortality. There were no differences in mortality between ECMO, IABP, microaxial ventricular assist device (mVAD), ECMO-mVAD, centrifugal VAD, or mVAD-IABP and no MCS (all very low certainty). Our one-stage IPD survival meta-analysis based on the stratified Cox model found only ECMO-IABP was associated with lower mortality (hazard ratio, HR, 0.55, 95% CI 0.46-0.66).

CONCLUSION

In patients with cardiogenic shock, ECMO-IABP may reduce mortality, while other MCS devices did not reduce mortality. However, this must be interpreted within the context of inter-study heterogeneity and limited certainty of evidence.

Intra-aortic balloon pump in patients with extracorporeal cardiopulmonary resuscitation after cardiac arrest caused by acute coronary syndrome

BACKGROUND

This study evaluated the association between intra-aortic balloon pump (IABP) use in patients with out-of-hospital cardiac arrest (OHCA) caused by acute coronary syndrome (ACS) who received extracorporeal cardiopulmonary resuscitation (ECPR) and 30-day outcomes.

METHODS

This study was a secondary analysis of data from the SAVE-J II study, a retrospective, multicenter registry study involving 36 participating institutions in Japan. Patients with cardiac arrest caused by ACS who received ECPR were divided into two groups depending on whether or not they received IABP. The primary outcome was 30-day survival. Subgroup analysis was performed to detect what type of patients were mostly associated with improved outcomes.

RESULTS

Of 2,157 patients registered in the SAVE-J II study, 877 patients were enrolled in this study, 702 patients in the IABP group and 175 patients in the non-IABP group. Multivariable logistic regression analysis did not reveal a significant difference in 30-day survival (OR 1.37, 95% CI 0.91-2.07, p = 0.13). In the subgroup analysis, 30-day survival among patients without percutaneous coronary intervention (PCI) and stenosis of multiple coronary vessels were associated with IABP use.

CONCLUSIONS

IABP use in patients with OHCA with ACS who received ECPR is not associated with 30-day survival. The use of IABP in patients who did not have PCI and have multiple coronary vessel stenoses warrants further study.

Changing Trends in Mechanical Circulatory Support Use and Outcomes in Patients Undergoing Percutaneous Coronary Interventions for Acute Coronary Syndrome Complicated With Cardiogenic Shock: Insights From a Nationwide Registry in Japan

BACKGROUND

Temporal trends in the management of acute coronary syndrome complicated with cardiogenic shock after the revision of guideline recommendations for intra-aortic balloon pump (IABP) use and the approval of the Impella require further investigation, because their impact remains uncertain.

METHODS AND RESULTS

Using the Japanese Percutaneous Coronary Intervention (J-PCI) registry database from 2019 to 2021, we identified 12 171 patients undergoing percutaneous coronary intervention for acute coronary syndrome complicated with cardiogenic shock under mechanical circulatory support. The patients were stratified into 3 groups: (1) IABP alone, (2) Impella, and (3) venoarterial extracorporeal membrane oxygenation (VA-ECMO); the VA-ECMO group was further stratified into (3a) VA-ECMO alone, (3b) VA-ECMO in combination with IABP, and (3c) VA-ECMO in combination with Impella. The quarterly prevalence and outcomes were reported. The use of IABP alone decreased significantly from 63.5% in the first quarter of 2019 to 58.3% in the fourth quarter of 2021 (P for trend=0.01). Among 4245 patients requiring VA-ECMO, the use of VA-ECMO in combination with IABP decreased significantly from 78.7% to 67.3%, whereas the use of VA-ECMO in combination with Impella increased significantly from 4.2% to 17.0% (P for trend <0.001 for both). After adjusting for the confounders, the risk difference in the fourth quarter of 2021 relative to the first quarter of 2019 for in-hospital mortality was not significant (adjusted odds ratio, 0.84 [95% CI, 0.69-1.01]).

CONCLUSIONS

Our study revealed substantial changes in the use of different mechanical circulatory support modalities in acute coronary syndrome complicated with cardiogenic shock, but they did not significantly improve the outcomes.

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

Background

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

Methods

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

Results

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

Conclusions

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

Beneficial Effects of IABP in Anterior Myocardial Infarction Complicated by Cardiogenic Shock

Background and Objectives. Recent guidelines have downgraded the routine use of the intra-aortic balloon pump (IABP) in patients with cardiogenic shock (CS) due to ST-elevation myocardial infarction (STEMI). Despite this, its use in clinical practice remains high. The aim of this study was to evaluate the prognostic impact of the IABP in patients with STEMI complicated by CS undergoing primary PCI (pPCI), focusing on patients with anterior MI in whom a major benefit has been previously hypothesized. Materials and Methods. We enrolled 2958 consecutive patients undergoing pPCI for STEMI in our department from 2005 to 2018. Propensity score matching and mortality analysis were performed. Results. CS occurred in 246 patients (8.3%); among these patients, 145 (60%) had anterior AMI. In the propensity-matched analysis, the use of the IABP was associated with a lower 30-day mortality (39.3% vs. 60.9%, p = 0.032) in the subgroup of patients with anterior STEMI. Conversely, in the whole group of CS patients and in the subgroup of patients with non-anterior STEMI, IABP use did not have a significant impact on mortality. Conclusions. The use of the IABP in cases of STEMI complicated by CS was found to improve survival in patients with anterior infarction. Prospective studies are needed before abandoning or markedly limiting the use of the IABP in this clinical setting.

Protocolised Management of Cardiogenic Shock and Shock Teams: A Narrative Review

Despite advances in therapy, the incidence of cardiogenic shock continues to increase, with significant mortality that has improved minimally over time. Treatment options for cardiogenic shock are complex and time-, resource-, and case volume-dependent, and involve multiple medical specialties. To provide early, more equitable, and standardised access to cardiogenic shock expertise with advanced therapies, cardiogenic shock teams with a protocolised treatment approach have been proposed. These processes have been applied across hospitals into integrated cardiogenic shock networks. This narrative review evaluates the role of cardiogenic shock teams, protocolised and regionalised shock networks, and the main individual components of protocolised shock management approaches.

Perspectives and Considerations of IABP in the Era of ECMO for Cardiogenic Shock

The development of mechanical circulatory support (MCS) has been rapid, and its use worldwide in patients with cardiogenic shock is increasingly widespread. However, current statistical data and clinical research do not demonstrate its significant improvement in the patient prognosis. This review focuses on the widely used intra-aortic balloon pumps (IABP) and veno-arterial extracorporeal membrane oxygenation (VA-ECMO), analyzing and comparing their characteristics, efficacy, risk of complications, and the current exploration status of left ventricular mechanical unloading. Subsequently, we propose a rational approach to viewing the negative outcomes of current MCS, and look ahead to the future development trends of IABP.

Trends in Mechanical Circulatory Support Use and Outcomes of Patients With Cardiogenic Shock in Japan, 2010 to 2020 (from a Nationwide Inpatient Database Study)

Little is known about the impact of the downgrade of guideline recommendations for intra-aortic balloon pump (IABP) use and the approval of the Impella in Japan, where IABPs have been predominantly used. This study aimed to describe the annual trends in the mechanical circulatory support (MCS) use and outcomes in patients with cardiogenic shock (CS) requiring MCS. Using the Japanese Diagnosis Procedure Combination database from July 2010 to March 2021, we identified inpatients with CS requiring MCS. The patients were stratified into 3 groups: (1) IABP alone, (2) Impella alone, and (3) extracorporeal membrane oxygenation (ECMO), regardless of IABP or Impella use. The patient characteristics and outcomes were reported by the fiscal year. Of the 160,559 eligible patients, 117,599 (73.2%) used IABP alone, 1,465 (0.9%) Impella alone, and 41,495 (25.8%) ECMO. The prevalence of the use of an IABP alone significantly decreased from 80.5% in 2010 to 65.3% in 2020 (p for trend <0.001), whereas the prevalence of the use of an Impella alone significantly increased from 0.0% to 5.0% and ECMO from 19.5% to 29.6% (p for trend <0.001 for both). In-hospital mortality significantly increased from 29.3% in 2010 to 32.6% in 2020 in the overall patients with CS requiring MCS but significantly decreased in those requiring ECMO from 73.7% to 64.1% (p for trend <0.001 for both). In conclusion, there were significant annual changes in the patterns of MCS use and clinical outcomes in patients with CS requiring MCS.

Intra-aortic and Intra-caval Balloon Pump Devices in Experimental Non-traumatic Cardiac Arrest and Cardiopulmonary Resuscitation

Intra-aortic balloon pump (IABP) use during CPR has been scarcely studied. Intra-caval balloon pump (ICBP) may decrease backward venous flow during CPR. Mechanical chest compressions (MCC) were initiated after 10 min of cardiac arrest in anesthetized pigs. After 5 min of MCC, IABP (n = 6) or ICBP (n = 6) was initiated. The MCC device and the IABP/ICBP had slightly different frequencies, inducing a progressive peak pressure phase shift. IABP inflation 0.15 s before MCC significantly increased mean arterial pressure (MAP) and carotid blood flow (CBF) compared to inflation 0.10 s after MCC and to MCC only. Coronary perfusion pressure significantly increased with IABP inflation 0.25 s before MCC compared to inflation at MCC. ICBP inflation before MCC significantly increased MAP and CBF compared to inflation after MCC but not compared to MCC only. This shows the potential of IABP in CPR when optimally synchronized with MCC. The effect of timing of intra-aortic balloon pump (IABP) inflation during mechanical chest compressions (MCC) on hemodynamics. Data from12 anesthetized pigs.

Trends in Intra-Aortic Balloon Pump Use in Cardiogenic Shock After the SHOCK-II Trial

Myocardial infarction complicated by cardiogenic shock (MI-CS) has a poor prognosis, even with early revascularization. Previously, intra-aortic balloon pump (IABP) use was thought to improve outcomes, but the IABP-SHOCK-II (Intra-aortic Balloon Pump in Cardiogenic Shock-II study) trial found no survival benefit. We aimed to determine the trends in IABP use in patients who underwent percutaneous intervention over time. Data were taken from patients in the Melbourne Interventional Group registry (2005 to 2018) with MI-CS who underwent percutaneous intervention. The primary outcome was the trend in IABP use over time. The secondary outcomes included 30-day mortality and major adverse cardiovascular and cerebrovascular events (MACCEs). Of the 1,110 patients with MI-CS, IABP was used in 478 patients (43%). IABP was used more in patients with left main/left anterior descending culprit lesions (62% vs 46%), lower ejection fraction (<35%; 18% vs 11%), and preprocedural inotrope use (81% vs 73%, all p <0.05). IABP use was associated with higher bleeding (18% vs 13%) and 30-day MACCE (58% vs 51%, both p <0.05). The rate of MI-CS per year increased over time; however, after 2012, there was a decrease in IABP use (p <0.001). IABP use was a predictor of 30-day MACCE (odds ratio 1.6, 95% confidence interval 1.18 to 2.29, p = 0.003). However, IABP was not associated with in-hospital, 30-day, or long-term mortality (45% vs 47%, p = 0.44; 46% vs 50%, p = 0.25; 60% vs 62%, p = 0.39). In conclusion, IABP was not associated with reduced short- or long-term mortality and was associated with increased short-term adverse events. IABP use is decreasing but is predominately used in sicker patients with greater myocardium at risk.

An empirical evaluation of the impact scenario of pooling bodies of evidence from randomized controlled trials and cohort studies in medical research

BACKGROUND

Randomized controlled trials (RCTs) and cohort studies are the most common study design types used to assess treatment effects of medical interventions. We aimed to hypothetically pool bodies of evidence (BoE) from RCTs with matched BoE from cohort studies included in the same systematic review.

METHODS

BoE derived from systematic reviews of RCTs and cohort studies published in the 13 medical journals with the highest impact factor were considered. We re-analyzed effect estimates of the included systematic reviews by pooling BoE from RCTs with BoE from cohort studies using random and common effects models. We evaluated statistical heterogeneity, 95% prediction intervals, weight of BoE from RCTs to the pooled estimate, and whether integration of BoE from cohort studies modified the conclusion from BoE of RCTs.

RESULTS

Overall, 118 BoE-pairs based on 653 RCTs and 804 cohort studies were pooled. By pooling BoE from RCTs and cohort studies with a random effects model, for 61 (51.7%) out of 118 BoE-pairs, the 95% confidence interval (CI) excludes no effect. By pooling BoE from RCTs and cohort studies, the median I² was 48%, and the median contributed percentage weight of RCTs to the pooled estimates was 40%. The direction of effect between BoE from RCTs and pooled effect estimates was mainly concordant (79.7%). The integration of BoE from cohort studies modified the conclusion (by examining the 95% CI) from BoE of RCTs in 32 (27%) of the 118 BoE-pairs, but the direction of effect was mainly concordant (88%).

CONCLUSIONS

Our findings provide insights for the potential impact of pooling both BoE in systematic reviews. In medical research, it is often important to rely on both evidence of RCTs and cohort studies to get a whole picture of an investigated intervention-disease association. A decision for or against pooling different study designs should also always take into account, for example, PI/ECO similarity, risk of bias, coherence of effect estimates, and also the trustworthiness of the evidence. Overall, there is a need for more research on the influence of those issues on potential pooling.

Mechanical Circulatory Support Devices for the Treatment of Cardiogenic Shock Complicating Acute Myocardial Infarction-A Review

Cardiogenic shock complicating acute myocardial infarction is a complex clinical condition associated with dismal prognosis. Routine early target vessel revascularization remains the most effective treatment to substantially improve outcomes, but mortality remains high. Temporary circulatory support devices have emerged with the aim to enhance cardiac unloading and improve end-organ perfusion. However, quality evidence to guide device selection, optimal installation timing, and post-implantation management are scarce, stressing the importance of multidisciplinary expert care. This review focuses on the contemporary use of short-term support devices in the setting of cardiogenic shock following acute myocardial infarction, including the common challenges associated this practice.

Impella versus Venoarterial Extracorporeal Membrane Oxygenation for Acute Myocardial Infarction Cardiogenic Shock: A Systematic Review and Meta-Analysis

Objectives: Despite an increase in the use of mechanical circulatory support (MCS) devices for acute myocardial infarction cardiogenic shock (AMI-CS), there is currently no randomised data directly comparing the use of Impella and veno-arterial extra-corporeal membrane oxygenation (VA-ECMO). Methods: Electronic databases of MEDLINE, EMBASE and CENTRAL were systematically searched in November 2021. Studies directly comparing the use of Impella (CP, 2.5 or 5.0) with VA-ECMO for AMI-CS were included. Studies examining other modalities of MCS, or other causes of cardiogenic shock, were excluded. The primary outcome was in-hospital mortality. Results: No randomised trials comparing VA-ECMO to Impella in patients with AMI-CS were identified. Six cohort studies (five retrospective and one prospective) were included for systematic review. All studies, including 7093 patients, were included in meta-analysis. Five studies reported in-hospital mortality, which, when pooled, was 42.4% in the Impella group versus 50.1% in the VA-ECMO group. Impella support for AMI-CS was associated with an 11% relative risk reduction in in-hospital mortality compared to VA-ECMO (risk ratio 0.89; 95% CI 0.83–0.96, I² 0%). Of the six studies, three studies also adjusted outcome measures via propensity-score matching with reported reductions in in-hospital mortality with Impella compared to VA-ECMO (risk ratio 0.72; 95% CI 0.59–0.86, I² 35%). Pooled analysis of five studies with 6- or 12-month mortality data reported a 14% risk reduction with Impella over the medium-to-long-term (risk ratio 0.86; 95% CI 0.76–0.97, I² 0%). Conclusions: There is no high-level evidence comparing VA-ECMO and Impella in AMI-CS. In available observation studies, MCS with Impella was associated with a reduced risk of in-hospital and medium-term mortality as compared to VA-ECMO.

Evaluating agreement between bodies of evidence from randomized controlled trials and cohort studies in medical research: a meta-epidemiological study

BACKGROUND

Randomized controlled trials (RCTs) and cohort studies are the most common study design types used to assess the treatment effects of medical interventions. To evaluate the agreement of effect estimates between bodies of evidence (BoE) from randomized controlled trials (RCTs) and cohort studies and to identify factors associated with disagreement.

METHODS

Systematic reviews were published in the 13 medical journals with the highest impact factor identified through a MEDLINE search. BoE-pairs from RCTs and cohort studies with the same medical research question were included. We rated the similarity of PI/ECO (Population, Intervention/Exposure, Comparison, Outcome) between BoE from RCTs and cohort studies. The agreement of effect estimates across BoE was analyzed by pooling ratio of ratios (RoR) for binary outcomes and difference of mean differences for continuous outcomes. We performed subgroup analyses to explore factors associated with disagreements.

RESULTS

One hundred twenty-nine BoE pairs from 64 systematic reviews were included. PI/ECO-similarity degree was moderate: two BoE pairs were rated as "more or less identical"; 90 were rated as "similar but not identical" and 37 as only "broadly similar". For binary outcomes, the pooled RoR was 1.04 (95% CI 0.97-1.11) with considerable statistical heterogeneity. For continuous outcomes, differences were small. In subgroup analyses, degree of PI/ECO-similarity, type of intervention, and type of outcome, the pooled RoR indicated that on average, differences between both BoE were small. Subgroup analysis by degree of PI/ECO-similarity revealed high statistical heterogeneity and wide prediction intervals across PI/ECO-dissimilar BoE pairs.

CONCLUSIONS

On average, the pooled effect estimates between RCTs and cohort studies did not differ. Statistical heterogeneity and wide prediction intervals were mainly driven by PI/ECO-dissimilarities (i.e., clinical heterogeneity) and cohort studies. The potential influence of risk of bias and certainty of the evidence on differences of effect estimates between RCTs and cohort studies needs to be explored in upcoming meta-epidemiological studies.

Ventricular Unloading Using the ImpellaTM Device in Cardiogenic Shock

Cardiogenic shock (CS) remains a leading cause of hospital death. However, the use of mechanical circulatory support has fundamentally changed CS management over the last decade and is rapidly increasing. In contrast to extracorporeal membrane oxygenation as well as counterpulsation with an intraaortic balloon pump, ventricular unloading by the Impella™ device actively reduces ventricular volume as well as pressure and augments systemic blood flow at the same time. By improving myocardial oxygen supply and enhancing systemic circulation, the Impella device potentially protects myocardium, facilitates ventricular recovery and may interrupt the shock spiral. So far, the evidence supporting the use of Impella™ in CS patients derives mostly from observational studies, and there is a need for adequate randomized trials. However, the Impella™ device appears a promising technology for management of CS patients. But a profound understanding of the device, its physiologic impact and clinical application are all important when evaluating CS patients for percutaneous circulatory support. This review provides a comprehensive overview of the percutaneous assist device Impella™. Moreover, it highlights in depth the rationale for ventricular unloading in CS and describes practical aspects to optimize care for patients requiring hemodynamic support.

Machine learning prediction model of acute kidney injury after percutaneous coronary intervention

Acute kidney injury (AKI) after percutaneous coronary intervention (PCI) is associated with a significant risk of morbidity and mortality. The traditional risk model provided by the National Cardiovascular Data Registry (NCDR) is useful for predicting the preprocedural risk of AKI, although the scoring system requires a number of clinical contents. We sought to examine whether machine learning (ML) techniques could predict AKI with fewer NCDR-AKI risk model variables within a comparable PCI database in Japan. We evaluated 19,222 consecutive patients undergoing PCI between 2008 and 2019 in a Japanese multicenter registry. AKI was defined as an absolute or a relative increase in serum creatinine of 0.3 mg/dL or 50%. The data were split into training (N = 16,644; 2008-2017) and testing datasets (N = 2578; 2017-2019). The area under the curve (AUC) was calculated using the light gradient boosting model (GBM) with selected variables by Lasso and SHapley Additive exPlanations (SHAP) methods among 12 traditional variables, excluding the use of an intra-aortic balloon pump, since its use was considered operator-dependent. The incidence of AKI was 9.4% in the cohort. Lasso and SHAP methods demonstrated that seven variables (age, eGFR, preprocedural hemoglobin, ST-elevation myocardial infarction, non-ST-elevation myocardial infarction/unstable angina, heart failure symptoms, and cardiogenic shock) were pertinent. AUC calculated by the light GBM with seven variables had a performance similar to that of the conventional logistic regression prediction model that included 12 variables (light GBM, AUC [training/testing datasets]: 0.779/0.772; logistic regression, AUC [training/testing datasets]: 0.797/0.755). The AKI risk model after PCI using ML enabled adequate risk quantification with fewer variables. ML techniques may aid in enhancing the international use of validated risk models.

Mechanical circulatory support in acute myocardial infarction and cardiogenic shock: Challenges and importance of randomized control trials

BACKGROUND

Acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) is associated with significant morbidity and mortality.

METHODS

We provide an overview of previously conducted studies on the use of mechanical circulatory support (MCS) devices in the treatment of AMI-CS and difficulties which may be encountered in conducting such trials in the United States.

RESULTS

Well powered randomized control trials are difficult to conduct in a critically ill patient population due to physician preferences, perceived lack of equipoise and challenges obtaining informed consent.

CONCLUSIONS

With growth in utilization of MCS devices in patients with AMI-CS, efforts to perform well-powered, randomized control trials must be undertaken.

Temporary mechanical circulatory support in cardiogenic shock

Cardiogenic shock (CS) represents one of the foremost concerns in the field of acute cardiovascular medicine. Despite major advances in treatment, mortality of CS remains high. International societies recommend the development of expert CS centers with standardized protocols for CS diagnosis and treatment. In these terms, devices for temporary mechanical circulatory support (MCS) can be used to support the compromised circulation and could improve clinical outcome in selected patient populations presenting with CS. In the past years, we have witnessed an immense increase in the utilization of MCS devices to improve the clinical problem of low cardiac output. Although some treatment guidelines include the use of temporary MCS up to now no large randomized controlled trial confirmed a reduction in mortality in CS patients after MCS and additional research evidence is necessary to fully comprehend the clinical value of MCS in CS. In this article, we provide an overview of the most important diagnostic and therapeutic modalities in CS with the main focus on contemporary MCS devices, current state of art and scientific evidence for its clinical application and outline directions of future research efforts.

Intra-aortic balloon pump for acute-on-chronic heart failure complicated by cardiogenic shock

The Intra-aortic balloon pump (IABP) is widely implanted as temporary mechanical circulatory support for cardiogenic shock (CS). However, its use is declining following the results of the IABP-SHOCK II trial, which failed to show a clinical benefit of IABP in acute coronary syndrome (ACS) related CS. Acute-on-chronic heart failure has become an increasingly recognized, distinct etiology of CS (HF-CS). The pathophysiology of HF-CS differs from ACS-CS, as it typically represents the progression from a state of congestion (with relatively preserved cardiac output) to a low output state with hypoperfusion. The IABP is a "volume displacement pump" that promotes forward flow from a high-capacitance reservoir to low-capacitance vessels, improving peripheral perfusion and decreasing left ventricular afterload in the setting of high filling pressures. The IABP can improve ventricular-vascular coupling and, therefore, myocardial energetics. Additionally, many HF-CS patients are candidates for cardiac replacement therapies (left ventricular assist device or heart transplantation), and, therefore, may benefit from a "bridge" strategy that stabilizes the hemodynamics and end-organ function in preparation for more durable therapies. Notably, the new United Network for Organ Sharing donor heart allocation system has recently prioritized patients on IABP support. This review describes the role of IABP for the treatment of HF-CS. It also briefly discusses new strategies for vascular access as well as a fully implantable versions for a longer duration of support.

High-Risk Percutaneous Coronary Intervention of Native Coronary Arteries Without Mechanical Circulatory Support in Acute Coronary Syndrome Without Cardiogenic Shock

Widespread utilization of mechanical circulatory support (MCS) for high-risk percutaneous coronary intervention (PCI) remains controversial, with a lack of randomized supporting evidence and associated risk of device-related complications. We investigated whether high-risk PCI of native coronary arteries without elective MCS in patients with acute coronary syndrome (ACS) is safe and feasible. We performed a single-center, retrospective analysis for ACS patients meeting American College of Cardiology high-risk criteria: unprotected left main disease, last remaining conduit, ejection fraction <35%, 3-vessel coronary artery disease, severe aortic stenosis, or severe mitral regurgitation. Patients with cardiogenic shock and those undergoing PCI of the bypass grafts were excluded. Major in-hospital and 30-day cardiovascular outcomes were assessed. From 2003 through 2018, 499 patients (847 lesions) with unstable angina pectoris (UAP), 1218 patients (1807 lesions) with non-ST-elevation myocardial infarction (NSTEMI), and 868 patients (1260 lesions) with ST-segment elevation myocardial infarction (STEMI) underwent high-risk PCI. Procedural success was achieved in 97.2% of UAP, 98.3% of NSTEMI, and 96.6% of STEMI patients. In-hospital and 30-day all-cause mortality were as follows: UAP, 2%; NSTEMI, 2.1%; and STEMI 4.7%. Bailout intra-aortic balloon pump was required in 1.6% of UAP, 3.1% of NSTEMI, and 10.3% of STEMI patients. Major complications for UAP, NSTEMI, and STEMI were, respectively: target lesion revascularization (2.3%, 1.4%, and 1.5%), stroke or transient ischemic attack (0.8%, 0.6%, and 1.3%), acute renal failure (8.2%, 7.2%, and 10.2%), major bleeding (1.6%, 3.1%, and 8.5%). In conclusion, our results show that high-risk PCI without elective MCS is safe and feasible in most ACS patients, challenging professional societies' current recommendations. A randomized trial comparing unprotected versus protected high-risk PCI for non-shock ACS patients is warranted.

ANMCO POSITION PAPER: Role of intra-aortic balloon pump in patients with acute advanced heart failure and cardiogenic shock

The treatment of patients with advanced acute heart failure is still challenging. Intra-aortic balloon pump (IABP) has widely been used in the management of patients with cardiogenic shock. However, according to international guidelines, its routinary use in patients with cardiogenic shock is not recommended. This recommendation is derived from the results of the IABP-SHOCK II trial, which demonstrated that IABP does not reduce all-cause mortality in patients with acute myocardial infarction and cardiogenic shock. The present position paper, released by the Italian Association of Hospital Cardiologists, reviews the available data derived from clinical studies. It also provides practical recommendations for the optimal use of IABP in the treatment of cardiogenic shock and advanced acute heart failure.

Intra-Aortic Balloon Pump as a Bridge to Durable Left Ventricular Assist Device

Left ventricular assist devices (LVAD) are increasingly being used as destination therapy in patients with Stage D heart failure. It has been reported that a majority of patients who receive a durable LVAD (dLVAD) present in cardiogenic shock due to decompensated heart failure (ADHF‐CS). As it stands, there is no consensus on the optimal management strategy for patients presenting with ADHF. Bridging with intra‐aortic balloon pumps (IABPs) continues to be a therapeutic option in patients with hemodynamic instability due to cardiogenic shock. The majority of data regarding the use of IABP in cardiogenic shock come from studies in patients presenting with acute myocardial infarction with cardiogenic shock and demonstrates that there is no benefit of routine IABP use in this patient population. However, the role of IABPs as a bridge to dLVAD in ADHF‐CS has yet to be determined. The hemodynamic changes seen in acute myocardial infarction with cardiogenic shock are known to be different and more acutely impaired than those presenting with ADHF‐CS as evidenced by differences in pressure/volume loops. Thus, data should not be extrapolated across these 2 very different disease processes. The aim of this review is to describe results from contemporary studies examining the use of IABPs as a bridge to dLVAD in patients with ADHF‐CS. Retrospective evidence from large registries suggests that the use of IABP as a bridge to dLVAD is feasible and safe when compared with other platforms of temporary mechanical circulatory support. However, there is currently a paucity of high‐quality evidence examining this increasingly important clinical question.

Combined use of venoarterial extracorporeal membrane oxygenation and intra-aortic balloon pump after cardiac arrest

OBJECTIVES

We investigated whether intra-aortic balloon pump (IABP) combined with venoarterial extracorporeal membrane oxygenation (VA-ECMO) was associated with favourable neurological outcomes for patients after the return of spontaneous circulation (ROSC). Moreover, we evaluated the aetiology of cardiac arrest on the effectiveness of this therapy in a sub-study.

BACKGROUND

There is insufficient research on the optimal combination of machines for patients after ROSC is not established.

METHODS

This is a large-scale, multicentre, 30-day cohort study. Among 80,716 patients who delivered to the emergency room, 935 patients treated with VA-ECMO after ROSC were included using the data from the Tokyo Cardiovascular Care Unit Network Registry between 2010 and 2017. The study patients were stratified according to the use of IABP [the ECMO + IABP group (n = 762) vs. the ECMO-alone group (n = 173)]. We also evaluated the cause of cardiac arrest [acute coronary syndrome (ACS) and non-ACS] in the sub-study. To adjust the patients' backgrounds, we used the propensity score matching for additional analyses. The endpoint was 30-day favourable neurological outcome.

RESULTS

The ECMO + IABP group showed significantly better neurological outcomes than the ECMO-alone group (crude; 35% vs. 25%; log-lank P < 0.001). In the ACS subgroup, the ECMO + IABP group showed significantly better neurological outcome (crude; 34% vs. 18%; log-lank P < 0.001), but not in the non-ACS subgroup (crude; 38% vs. 32%; log-lank P = 0.11). These results are similar after adjustments to their backgrounds using propensity matching.

CONCLUSIONS

Compared to VA-ECMO alone, the combined use of VA-ECMO and IABP is associated with better neurological outcomes after ROSC, especially in complicated ACS.

Effects of mechanical circulatory support devices in patients with acute myocardial infarction undergoing stent implantation: a systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

The survival benefit of using mechanical circulatory support (MCS) in patients with acute myocardial infarction (AMI) is still controversial. It is necessary to explore the impact on clinical outcomes of MCS in patients with AMI undergoing stenting.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Embase, Cochrane Library, Medline, PubMed, Web of Science, ClinicalTrials.gov and Clinicaltrialsregister.eu databases were searched from database inception to February 2021.

ELIGIBILITY CRITERIA

Randomised clinical trials (RCTs) on MCS use in patients with AMI undergoing stent implantation were included.

DATA EXTRACTION AND SYNTHESIS

Data were extracted and summarised independently by two reviewers. Risk ratios (RRs) and 95% CIs were calculated for clinical outcomes according to random-effects model.

RESULTS

Twelve studies of 1497 patients with AMI were included, nine studies including 1382 patients compared MCS with non-MCS, and three studies including 115 patients compared percutaneous ventricular assist devices (pVADs) versus intra-aortic balloon pump (IABP). Compared with non-MCS, MCS was not associated with short-term (within 30 days) (RR=0.90; 95% CI 0.57 to 1.41; I²=46.8%) and long-term (at least 6 months) (RR=0.82; 95% CI 0.57 to 1.17; I²=37.6%) mortality reductions. In the subset of patients without cardiogenic shock (CS) compared with non-MCS, the patients with IABP treatment significantly had decreased long-term mortality (RR=0.49; 95% CI 0.27 to 0.90; I²=0), but without the short-term mortality reductions (RR=0.51; 95% CI 0.22 to 1.19; I²=17.9%). While in the patients with CS, the patients with MCS did not benefit from the short-term (RR=1.09; 95% CI 0.67 to 1.79; I²=46.6%) or long-term (RR=1.00; 95% CI 0.75 to 1.33; I²=22.1%) survival. Moreover, the application of pVADs increased risk of bleeding (RR=1.86; 95% CI 1.15 to 3.00; I²=15.3%) compared with IABP treatment (RR=1.86; 95% CI 1.15 to 3.00; I²=15.3%).

CONCLUSIONS

In all patients with AMI undergoing stent implantation, the MCS use does not reduce all-cause mortality. Patients without CS can benefit from MCS regarding long-term survival, while patients with CS seem not.

Mechanical Support in Early Cardiogenic Shock: What Is the Role of Intra-aortic Balloon Counterpulsation?

Purpose of Review

We aim to summarize recent insights and provide an up-to-date overview on the role of intra-aortic balloon pump (IABP) counterpulsation in cardiogenic shock (CS).

Recent Findings

In the largest randomized controlled trial (RCT) of patients with CS after acute myocardial infarction (AMICS), IABP did not lower mortality. However, recent data suggest a role for IABP in patients who have persistent ischemia after revascularization. Moreover, in the growing population of CS not caused by acute coronary syndrome (ACS), multiple retrospective studies and one small RCT report on significant hemodynamic improvement following (early) initiation of IABP support, which allowed bridging of most patients to recovery or definitive therapies like heart transplant or a left ventricular assist device (LVAD).

Summary

Routine use of IABP in patients with AMICS is not recommended, but many patients with CS either from ischemic or non-ischemic cause may benefit from IABP at least for hemodynamic improvement in the short term. There is a need for a larger RCT regarding the role of IABP in selected patients with ACS, as well as in patients with non-ACS CS.

Axial flow ventricular assist devices in cardiogenic shock complicating acute myocardial infarction

Cardiogenic shock (CS) remains the leading cause of death in patients hospitalised with acute myocardial infarction with mortality as high as 40%-50% prior to hospital discharge. The failure of inotropic therapy to maintain adequate perfusion and to prevent irreversible end-organ failure has led to attempts to improve outcomes by mechanical circulatory support (MCS) devices. Axial flow ventricular assist devices, namely Impella, are an attractive therapeutic option due to their positive haemodynamic benefits and ease of use. Despite clear beneficial haemodynamic effects, which should significantly impact on the pathophysiology of CS, there are currently no clear data to support their use in the reduction of clinical end points such as cardiac death. This review summarises and critically evaluates the current scientific evidence for the use of axial flow ventricular assist devices and highlights gaps in our understanding. Given such gaps, a consensus multidisciplinary approach, predicated on emphasising timely diagnosis and appropriate use of MCS, is vital to ensure that the right patient is paired with the right device at the right time.

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

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

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

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

Mechanical Circulatory Support in Acute Myocardial Infarction and Cardiogenic Shock

Mechanical circulatory support devices are increasingly used for the treatment of acute myocardial infarction complicated by cardiogenic shock. These devices provide different levels of univentricular and biventricular support, have different mechanisms of actions, and provide different physiologic effects. Institutions require expert teams to safely implant and manage these devices. This article reviews the mechanism of action, physiologic effects, and data as they relate to the utilization of these devices.

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.

Use of Mechanical Circulatory Support Devices Among Patients With Acute Myocardial Infarction Complicated by Cardiogenic Shock

IMPORTANCE

Mechanical circulatory support (MCS) devices, including intravascular microaxial left ventricular assist devices (LVADs) and intra-aortic balloon pumps (IABPs), are used in patients who undergo percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) complicated by cardiogenic shock despite limited evidence of their clinical benefit.

OBJECTIVE

To examine trends in the use of MCS devices among patients who underwent PCI for AMI with cardiogenic shock, hospital-level use variation, and factors associated with use.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study used the CathPCI and Chest Pain-MI Registries of the American College of Cardiology National Cardiovascular Data Registry. Patients who underwent PCI for AMI complicated by cardiogenic shock between October 1, 2015, and December 31, 2017, were identified from both registries. Data were analyzed from October 2018 to August 2020.

EXPOSURES

Therapies to provide hemodynamic support were categorized as intravascular microaxial LVAD, IABP, TandemHeart, extracorporeal membrane oxygenation, LVAD, other devices, combined IABP and intravascular microaxial LVAD, combined IABP and other device (defined as TandemHeart, extracorporeal membrane oxygenation, LVAD, or another MCS device), or medical therapy only.

MAIN OUTCOMES AND MEASURES

Use of MCS devices overall and specific MCS devices, including intravascular microaxial LVAD, at both patient and hospital levels and variables associated with use.

RESULTS

Among the 28 304 patients included in the study, the mean (SD) age was 65.4 (12.6) years and 18 968 were men (67.0%). The overall MCS device use was constant from the fourth quarter of 2015 to the fourth quarter of 2017, although use of intravascular microaxial LVADs significantly increased (from 4.1% to 9.8%; P < .001), whereas use of IABPs significantly decreased (from 34.8% to 30.0%; P < .001). A significant hospital-level variation in MCS device use was found. The median (interquartile range [IQR]) proportion of patients who received MCS devices was 42% (30%-54%), and the median proportion of patients who received intravascular microaxial LVADs was 1% (0%-10%). In multivariable analyses, cardiac arrest at first medical contact or during hospitalization (odds ratio [OR], 1.82; 95% CI, 1.58-2.09) and severe left main and/or proximal left anterior descending coronary artery stenosis (OR, 1.36; 95% CI, 1.20-1.54) were patient characteristics that were associated with higher odds of receiving intravascular microaxial LVADs only compared with IABPs only.

CONCLUSIONS AND RELEVANCE

This study found that, among patients who underwent PCI for AMI complicated by cardiogenic shock, overall use of MCS devices was constant, and a 2.5-fold increase in intravascular microaxial LVAD use was found along with a corresponding decrease in IABP use and a significant hospital-level variation in MCS device use. These trends were observed despite limited clinical trial evidence of improved outcomes associated with device use.

The Preference, Effect, and Prognosis of Intra-Aortic Balloon Counterpulsation in Acute Myocardial Infarction Complicated by Cardiogenic Shock Patients: A Retrospective Cohort Study

BACKGROUNDS

Intra-aortic balloon counterpulsation is increasingly used in acute myocardial infarction complicated by cardiogenic shock. The aim of this study was to explore the preference, effect, and prognosis of intra-aortic balloon counterpulsation in acute myocardial infarction complicated by cardiogenic shock patients.

METHODS

Data of acute myocardial infarction complicated by cardiogenic shock patients at the Fourth Medical Center of PLA General Hospital were collected retrospectively. A propensity score was calculated with a logistic regression which contained clinically meaningful variables and variables selected by Lasso and then used to match the control group. The cumulative incidence curve and Gray's test were employed to analyse the effect and prognosis of intra-aortic balloon counterpulsation on mortality.

RESULTS

A total of 1962 acute myocardial infarction cases admitted between May 2015 and November 2018 were identified, and 223 cases with acute myocardial infarction complicated by cardiogenic shock were included as the study cohort, which contained 34 cases that received IABP and 189 cases that did not receive IABP. Patients with higher alanine aminotransferase (OR = 1.93, 95% CI 1.29-2.98), higher triglyceride (OR = 3.71, 95% CI 1.87-7.95), and higher blood glucose (OR = 1.08, 95% CI 0.99-1.18) had a higher probability of receiving intra-aortic balloon counterpulsation. In the propensity score matching analysis, 34 cases received intra-aortic balloon counterpulsation and 102 matched controls were included in the comparison. By comparing the cumulative incidence of in-hospital mortality, there was no statistically significant difference between the intra-aortic balloon counterpulsation group and matched control group (P = 0.454).

CONCLUSION

The use of intra-aortic balloon counterpulsation may not improve the prognosis of the acute myocardial infarction complicated by cardiogenic shock patients.

The role of mechanical support devices during percutaneous coronary intervention

The practice of interventional cardiology has changed dramatically over the last four decades since Andreas Gruentzig carried out the first balloon angioplasty. The obvious technological improvements in stent design and interventional techniques have facilitated the routine treatment of a higher risk cohort of patients, including those with complex coronary artery disease and poor left ventricular function, and more often in the setting of cardiogenic shock (CS) complicating acute myocardial infarction (AMI). The use of mechanical cardiac support (MCS) in these settings has been the subject of intense interest, particularly over the past decade . A number of commercially available devices now add to the interventional cardiologist's armamentarium when faced with the critically unwell or high-risk patient in the cardiac catheter laboratory. The theoretical advantage of such devices in these settings is clear- an increase in cardiac output and hence mean arterial pressure, with variable effects on coronary blood flow. In doing so, they have the potential to prevent the downward cascade of ischaemia and hypoperfusion, but there is a paucity of evidence to support their routine use in any patient subset, even those presenting with cardiogenic shock. This review will discuss the use and haemodynamic effect of MCS devices during percutaneous coronary intervention (PCI), and also examine the clinical evidence for their use in patients with cardiogenic shock, and those undergoing 'high risk' PCI.

Percutaneous coronary intervention assisted by invasive mechanical ventilation and intra-aortic balloon pump for acute myocardial infarction with cardiogenic shock: Retrospective cohort study and meta-analyses

There is little evidence to recommend the optimal invasive mechanical ventilation (IMV) modes and ideal positive end-expiratory pressure stress levels for acute myocardial infarction-cardiogenic shock (AMI-CS) patients. The aim of this study was to compare the mortality outcome in patients with AMI-CS who were treated with percutaneous coronary intervention (PCI) assisted by intra-aortic balloon pump (IABP) + IMV with historical controls. From January 1, 2016 to June 1, 2017, 60 patients were retrospectively enrolled at Tianjin Chest Hospital. Out of these, 88.3% of patients achieved thrombolysis in myocardial infarction (TIMI) flow 3 after PCI. The all-cause mortality rate in-hospital and at 1 year was 25% (95% CI: 0.14–0.36) and 33.9% (0.22–0.46), respectively. A systematic review followed by meta-analysis was performed with four historical studies of patients treated by PCI + IMV with partial IABP, which found an in-hospital mortality rate of 66.0% (95% CI: 0.62–0.71). Recently, a meta-analysis of patients receiving PCI + IABP with partial IMV showed that the 1 year mortality rate was 52.2% (95% CI: 0.47–0.58). In Cox regression analysis of patient data from the current study, lactic acid level ≥4.5 mmol/L, hyperuricemia, and TIMI flow <3 were independent predictors of death at 1 year. All-cause mortality, in-hospital and at 1 year, in patients with AMI-CS treated with PCI + IABP and IMV was lower than in those treated with PCI + partial IABP or IMV. Larger, longer-term direct comparisons are warranted.

Acute myocardial infarction and cardiogenic shock: Should we unload the ventricle before percutaneous coronary intervention?

Despite early reperfusion and coordinated systems of care, cardiogenic shock (CS) remains the number one cause of morbidity and in-hospital mortality following acute myocardial infarction (AMI). CS is a complex clinical syndrome that begins with hemodynamic instability and can progress to multi-organ failure and profound hemo-metabolic compromise. To improve outcomes, a clear understanding of the treatment objectives in CS and developing time-sensitive management strategies aimed at stabilizing hemodynamics and restoring myocardial perfusion are critical. Left ventricular (LV) load has been identified as an independent predictor of heart failure and mortality following AMI. Decades of preclinical and clinical research have identified several effective LV unloading strategies. Recent initiatives from single and multi-center registries and more recently the Door to Unload (DTU)-STEMI pilot study have provided valuable insight to developing a standardized treatment approach to AMI, based on early invasive hemodynamics and tailored circulatory support to unload the LV. To follow is a review of the pathophysiology and prevalence of shock, limitations of current therapies, and the pre-clinical and translational basis for incorporating LV unloading into contemporary AMI and shock care.

Timing of initiation of intra-aortic balloon pump in patients with acute myocardial infarction complicated by cardiogenic shock: A meta-analysis

BACKGROUND

For patients with acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) undergoing primary percutaneous coronary intervention (PCI), the optimal timing of the initiation of intra-aortic balloon pump (IABP) therapy remains unclear. Therefore, we performed the first meta-analysis to compare the outcomes of IABP insertion before vs after primary PCI in this population.

METHODS

Electronic databases of PubMed, EMBASE, and Cochrane Library were comprehensively searched from inception to April 1, 2019, to identify the eligible studies. The main outcomes were short-term (in-hospital or 30 days) and long-term (≥ 6 months) mortality. In addition, pooled analysis of risk-adjusted data were also performed to control for confounding factors.

RESULTS

Seven observational studies and two sub-analysis of randomized controlled trials involving 1348 patients were included. Compared to patients inserted IABP after PCI, patients who received IABP therapy before primary PCI had similar risks of short-term (odds ratio [OR] 0.88, 95% CI 0.49 to 1.59) and long-term (OR 0.99, 95% CI 0.58 to 1.68) all-cause mortality. Moreover, a pooled analysis of risk-adjusted data also found similar effects of the two therapies on short-term (OR 0.65, 95% CI 0.34 to 1.25) and long-term (OR 0.68, 95% CI 0.17 to 2.72) mortality. Besides, no significant difference was found between the two groups with respect to reinfarction, repeat revascularization, stroke, renal failure, and major bleeding.

CONCLUSIONS

The timing of the initiation of IABP therapy does not appear to impact short-term and long-term survival in patients with AMI complicated by CS undergoing primary PCI.