Which factors determine the development of late potentials after first myocardial infarction? A multifactorial analysis.
A multifactorial analysis was performed to study the factors that contributed to the occurrence of late potentials on the signal-averaged electrocardiogram in 106 consecutive patients with a first myocardial infarction. Ninety-three (88%) patients received intravenous thrombolytic therapy within 6 hours of symptom onset. Thirty-two (30%) patients had a late potential on the signal-averaged electrocardiogram on day 6, including 17 of 31 (55%) in whom the infarct-related artery was occluded and 15 of 75 (20%) in whom it was patent (P = 0.0004). Twenty-three variables were analyzed by a multifactorial stepwise regression analysis. Predictors of a late potential were (1) an occluded infarct-related coronary artery (t = -3.653, P = 0.0004) and (2) the extent of myocardial necrosis as indicated by the peak serum lactate dehydrogenase level (t = 3.094, P = 0.0025). The lower incidence of late potentials when the infarct-related coronary artery was patent was independent of left ventricular ejection fraction and peak enzyme levels after infarction.
McClements
B
B
Regional Medical Cardiology Centre, Royal Victoria Hospital, Belfast, United Kingdom.
Adgey
A A
AA
Mackenzie
G
G
D001145:Arrhythmias, Cardiac / Q000453:epidemiology* / Q000209:etiology; D003327:Coronary Disease / Q000453:epidemiology; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications* / Q000503:physiopathology; D012044:Regression Analysis; D012307:Risk Factors; D012815:Signal Processing, Computer-Assisted; D015912:Thrombolytic Therapy; D013997:Time Factors; D014654:Vascular Patency / Q000502:physiology