Abstract
Background
Sustained ventricular arrhythmias (VAs) and death are feared events post myocardial infarction (post-MI). Patients with heart failure post-MI have higher risk of VAs, compared to those without heart failure. Although the risk of sudden cardiac arrest and death post-MI isn't small, previous clinical trials have failed to demonstrate the benefit of early use of implantable cardioverter defibrillators. Moreover, little is known about the relationship between the acute phase and the late phase VAs in patients with heart failure post-MI.
Purpose
The aim of this study was to determine the predictors of the late phase VAs in patients with heart failure post MI.
Methods
We retrospectively analyzed our database of MI patients from January 2012 to September 2016.
Results
A total of consecutive 460 post-MI patients were included in this study (age, 67±12 year-old; male, 336 (73%); STEMI, 281 (61%)). All the patients underwent primary percutaneous coronary intervention. Of those, 90 patients (20%) had depressed left ventricular ejection fraction (LVEF) ≤35%. After a mean follow up period of 30±16 months, 45 patients (50%) had VAs after MI. Among them, 35 patients (78%) had VAs within 48 hours after MI onset, 8 patients (18%) within 7 days 48 hours later, and 21 patients (47%) more than 7 days. Cox-regression analysis showed that VAs within 7 days 48 hours later after MI onset was significantly related to sustained VAs more than 7 days after MI onset (Hazard Ratio, 4.97; 95% Confidence Interval, 1.31–18.9; p=0.019).
Conclusions
VAs in the sub-acute phase after MI predicted sustained VAs in the late phase in this population. Prompt initiation of aggressive antiarrhythmic therapies, including catheter ablation, after MI should be considered to reduce the mortality.
Autonomic changes in patients with heart failure and in post-myocardial infarction patients
