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

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.

Mechanical circulatory support in cardiogenic shock

Cardiogenic shock is a complex and diverse pathological condition characterized by reduced myocardial contractility. The goal of treatment of cardiogenic shock is to improve abnormal hemodynamics and maintain adequate tissue perfusion in organs. If hypotension and insufficient tissue perfusion persist despite initial therapy, temporary mechanical circulatory support (t-MCS) should be initiated. This decade sees the beginning of a new era of cardiogenic shock management using t-MCS through the accumulated experience with use of intra-aortic balloon pump (IABP) and venoarterial extracorporeal membrane oxygenation (VA-ECMO), as well as new revolutionary devices or systems such as transvalvular axial flow pump (Impella) and a combination of VA-ECMO and Impella (ECPELLA) based on the knowledge of circulatory physiology. In this transitional period, we outline the approach to the management of cardiogenic shock by t-MCS. The management strategy involves carefully selecting one or a combination of the t-MCS devices, taking into account the characteristics of each device and the specific pathological condition. This selection is guided by monitoring of hemodynamics, classification of shock stage, risk stratification, and coordinated management by the multidisciplinary shock team.

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.