Ischemic Burden in Patients Experiencing Primary Ventricular Fibrillation

Objectives: primary ventricular fibrillation (PVF) occurs in nearly 5% of patients with acute myocardial infarction (AMI), and is a major cause of sudden cardiac death (SCD). The predictors of PVF are unknown. The aim of this study to determine whether patients with AMI experiencing PVF have a greater cardiac ischemic burden than those not experiencing PVF.

Materials and Methods: a retrospective case-control study. Demographic characteristics were examined and compared between two groups: 1) AMI with PVF; 2) AMI without PVF. Collected data included: demographic information, risk factors (smoking, Hypertension, Obesity, previous MI, hyperlipidemia and family history), PCI results, heart function (EF). We also evaluated the "ischemic burden" (IB, number of coronary vessels in each patient)

Results: We found 73 patients who had STEMI with primary VF among them 65 males (89%) and 8 (11%) the average age 56.0 ± 11.9. There was no significant statistical difference between the control and study groups regarding smoking (p = 0.205), family history (p = 0.829), Hyperlipidemia (p = 0.239) previous MI (p = 0.093) and obesity (p = 0.148). However, there are statistically significant fewer patients with hypertension (p = 0.023) and diabetes (p = 0.03) in the study group. There were significantly more patients with moderate or severe LV dysfunction in the group patients with PVF (30.9% vs. 11%, p = 0.006). There was no significant statistical difference in the number of vessels involved ("IB") between the two groups (p = 0.466).

Conclusions: this study failed to prove a higher ischemic burden in patients who developed PVF during STEMI and survived their hospitalization. However, we were able to show that reduced left ventricular function early after myocardial infarction is a risk factor for PVF, and that hypertension and diabetes may protect from experiencing PVF.