[Relationship between arrhythmia profile, left ventricular function and sudden death in the post-infarct period of...

In order to determine the relationship among ventricular arrhythmias, left ventricular dysfunction and sudden cardiac death (SCD), 75 consecutive patients with myocardial infarction, 38 of whom resuscitated from SCD, were studied retrospectively by 48 hour Holter electrocardiographic monitoring (ECGD), cardiac catheterization and radionuclide angiography (ACRD). The patients were divided in 3 groups, related to SCD occurrence and to the interval between acute myocardial infarction (AMI) and SCD: Group I (37 patients-control group) no cardiac arrest occurred; Group II (26 patients) resuscitated less than or equal to 48 hours after AMI; Group III (12 patients) resuscitated 6-12 weeks after AMI. ECGDs were recorded with an average of 2 (ECGD 1), 16 (ECGD 2) and 36 months (ECGD 3) after AMI. In ECGD 1, there were no differences in the frequency and complexity of ventricular arrhythmias among the 3 groups, whereas in ECGD 2 and 3 the incidence of complex ventricular arrhythmias was significantly higher in Group III than in the other 2 groups (p less than 0.05). In Group III, the complexity and frequency of ventricular arrhythmias increased both in ECGD 2 and 3 compared to ECGD 1 (p less than 0.05). Furthermore, between patients of Group II and III higher grade arrhythmias and more frequent ventricular premature beats (VPB) were noted in sudden death patients than in survivors. There was no statistical difference in mean cardiac index, left ventricular end-diastolic pressure and ejection fraction among the groups. In the ACRD 1 performed an average of 8 months after AMI, a slight decrease of ejection fraction in Group III compared to the other groups was noted (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)