Post-Infectious Myocardial Infarction: New Insights for Improved Screening

Area of Science:

• Cardiology
• Infectious Diseases
• Epidemiology

Background:

• Acute infections are increasingly suspected as a factor in acute myocardial infarction (MI) development.
• Understanding the incidence, mechanisms, and outcomes of post-infectious MI is crucial for patient care.

Purpose of the Study:

• To determine the incidence, pathogenesis, and prognosis of myocardial infarction (MI) occurring concurrently with acute infection.
• To compare the characteristics and outcomes of post-infectious MI with other forms of MI.

Main Methods:

• Prospective enrollment of consecutive patients hospitalized for acute MI in coronary care units.
• Classification of MI into Type 1 (plaque disruption) or Type 2 (supply/demand imbalance) based on the universal definition.
• Adjudication of concurrent acute infection at the time of MI diagnosis.

Main Results:

• 10% of 4573 acute MI patients (466) had a concurrent acute infection, predominantly respiratory tract infections (67%).
• Type 2 MI was prevalent in 72% of post-infectious MI cases.
• Post-infectious MI showed higher in-hospital mortality (11% vs. 6%) and cardiovascular mortality compared to non-infectious MI, though this association attenuated after confounder adjustment.
• Type 1 MI and respiratory tract infections within the post-infectious group were linked to significantly worse prognosis.

Conclusions:

• Post-infectious MI is a common occurrence, representing 10% of all acute MI cases.
• Concurrent acute infection, especially respiratory infections, significantly increases in-hospital mortality in MI patients.
• Type 1 MI and respiratory infections are independent predictors of worse outcomes in the context of post-infectious MI.