Sudden death in patients with myocardial infarction and left ventricular dysfunction, heart failure, or both

Area of Science:

• Cardiology
• Clinical Medicine
• Public Health

Background:

• Survivors of acute myocardial infarction (MI) with reduced left ventricular systolic function face an elevated risk of sudden cardiac death.
• Assessing the temporal patterns of sudden death risk in these high-risk post-MI patients is critical for timely intervention.

Purpose of the Study:

• To evaluate the incidence and timing of sudden death or cardiac arrest with resuscitation in patients post-myocardial infarction.
• To determine the relationship between left ventricular ejection fraction and the risk of sudden cardiac events.

Main Methods:

• A cohort of 14,609 patients with post-myocardial infarction left ventricular dysfunction, heart failure, or both was analyzed.
• The study assessed the incidence and timing of sudden unexpected death or cardiac arrest with resuscitation relative to left ventricular ejection fraction.

Main Results:

• An event (sudden death or cardiac arrest with resuscitation) occurred in 7% of patients (1067/14,609) at a median of 180 days post-MI.
• The highest risk of sudden death was observed within the first 30 days post-MI (1.4% per month), particularly in patients with left ventricular ejection fraction ≤30% (2.3% per month).
• A 5-percentage-point decrease in left ventricular ejection fraction was associated with a 21% increased adjusted risk of sudden death or cardiac arrest within the first 30 days.

Conclusions:

• Sudden death risk is significantly elevated in the initial 30 days following myocardial infarction for patients with left ventricular dysfunction or heart failure.
• Earlier implementation of preventative strategies for sudden death is recommended for selected high-risk post-MI patients.