The AGNES case-control set consists of individuals with a first acute ST-elevation myocardial
infarction. AGNES cases have ECG- registered ventricular fibrillation occurring before
reperfusion therapy for an acute and first ST-elevation myocardial infarction. AGNES controls
are individuals with a first acute ST-elevation myocardial infarction but without ventricular
fibrillation. All cases and controls are recruited at seven heart centers in The Netherlands.
The investigators' exclude individuals with an actual non-ST-elevation myocardial infarction,
prior myocardial infarction, congenital heart defects, known structural heart disease, severe
comorbidity, electrolyte disturbances, trauma at presentation, recent surgery, previous
coronary artery bypass graft or use of class I and III antiarrhythmic drugs. Individuals who
develop ventricular fibrillation during or after percutaneous coronary intervention are not
eligible. Furthermore, because early reperfusion limits the opportunity of developing
ventricular fibrillation, potential control subjects undergoing percutaneous coronary
intervention within 2 h after onset of myocardial ischemia symptoms were not included. This
time interval is based on the observation that >90% of cases develop ventricular fibrillation
within 2 h after onset of the complaint of symptoms.