Characteristics and prognostic importance of ST-segment elevation on Holter monitoring early after acute myocardial infarction.
The correlation between episodes of ST-segment elevation on Holter monitoring, clinical characteristics, left ventricular function, exercise testing, and long-term prognosis was determined in 123 consecutive patients 55 +/- 8 years old (mean +/- SD) with a first acute myocardial infarction (AMI). During 36 hours of Holter recording 11 +/- 5 days after AMI, 11 patients (9%) had 91 episodes of ST-segment elevation (group 1), whereas 112 patients had no such episodes (group 2). Most episodes of ST-segment elevation occurred in leads with pathologic Q waves or small, indistinct R waves. Large, anterior Q-wave AMIs were more prevalent in group 1 than in group 2, and in-hospital heart failure also occurred more frequently in group 1 patients (82% vs 23%; p < 0.0005). Regional and global left ventricular function was reduced in group 1 compared with group 2: ejection fraction 33 +/- 11% vs 50 +/- 11% (p = 0.0001). All episodes of ST-segment elevation were asymptomatic and did not correlate with different indicators of myocardial ischemia. Indeed, exercise-induced ST-segment depression was more prevalent in group 2 than in group 1: 57 vs 18% (p < 0.035). Over a mean of 5 years (range 4 to 6) of follow-up, an association between episodes of ST-segment elevation on Holter monitoring and (1) cardiac death (Kaplan-Meier analysis; p < 0.005), and (2) cardiac death and nonfatal reinfarction (Kaplan-Meier analysis; p < 0.025) was found.(ABSTRACT TRUNCATED AT 250 WORDS)
Mickley
H
H
Department of Cardiology B, Odense University Hospital, Denmark.
Nielsen
J R
JR
Berning
J
J
Junker
A
A
Møller
M
M
D004452:Echocardiography / Q000379:methods / Q000706:statistics & numerical data; D015716:Electrocardiography, Ambulatory / Q000379:methods / Q000706:statistics & numerical data; D005080:Exercise Test / Q000379:methods / Q000706:statistics & numerical data; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology; D011379:Prognosis; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D013997:Time Factors; D016277:Ventricular Function, Left