Cardiogenic shock as a complication of acute myocardial infarction: a nationwide cohort study

Area of Science:

• Cardiology
• Critical Care Medicine
• Epidemiology

Background:

• Cardiogenic shock (CS) is a severe complication of acute myocardial infarction (AMI).
• Understanding the real-world incidence, characteristics, and outcomes of AMI-CS, especially concerning age, is crucial for patient management.
• Previous studies may not fully capture the contemporary landscape of AMI-CS in diverse age groups.

Purpose of the Study:

• To evaluate the real-world incidence and characteristics of patients experiencing AMI complicated by CS (AMI-CS).
• To compare outcomes, including short- and long-term mortality, between AMI-CS patients and those with AMI but without CS, stratified by age.
• To identify risk factors associated with AMI-CS across different age demographics.

Main Methods:

• A nationwide cohort study utilizing data from the Norwegian Myocardial Infarction Registry (2013-2022).
• Inclusion criteria encompassed all patients under 85 years with AMI.
• Outcomes, specifically all-cause mortality, were analyzed using Kaplan-Meier curves, Life Tables, and multivariable Cox regression models.

Main Results:

• The incidence of CS in AMI patients was 2.7% for those <75 years and 3.9% for those 75-84 years.
• AMI-CS patients were more likely to have comorbidities like heart failure, diabetes, and renal failure, and presented more often with ST-elevation AMI.
• In-hospital mortality was significantly higher in older AMI-CS patients (71.4% for 75-84 years vs. 47.5% for <75 years), with one-year cumulative mortality rates of 79.8% and 54.7%, respectively.

Conclusions:

• In-hospital mortality for AMI-related CS remains alarmingly high, with a pronounced increase in patients aged 75 years and older.
• For AMI-CS patients who survive hospitalization, the long-term mortality risk is only moderately elevated compared to AMI patients without CS.
• These findings underscore the critical need for improved acute management strategies and long-term follow-up for patients experiencing cardiogenic shock post-myocardial infarction.