Sudden death after myocardial infarction.
BACKGROUND
Sudden cardiac death after myocardial infarction (MI) has not been assessed recently in the community. Risk stratification for sudden cardiac death after MI commonly relies on baseline characteristics and little is known about the relationship between recurrent ischemia or heart failure and sudden cardiac death.


OBJECTIVE
To evaluate the risk of sudden cardiac death after MI and the impact of recurrent ischemia and heart failure on sudden cardiac death.


METHODS
Population-based surveillance study of 2997 residents (mean [SD] age, 67 [14] years; 59% were men) experiencing an MI in Olmsted County, Minnesota, between 1979 and 2005, and followed up through February 29, 2008.


METHODS
Sudden cardiac death defined as out-of-hospital death due to coronary disease; and observed survival free of sudden cardiac death compared with that expected in Olmsted County, Minnesota.


RESULTS
During a median follow-up of 4.7 years (25th-75th percentile, 1.6-7.1 years), 1160 deaths occurred, 282 from sudden cardiac death (24%). The 30-day cumulative incidence of sudden cardiac death was 1.2% (95% confidence interval [CI], 0.8%-1.6%). Thereafter, the rate of sudden cardiac death was constant at 1.2% per year yielding a 5-year cumulative incidence of 6.9% (95% CI, 5.9%-7.9%). The 30-day incidence of sudden cardiac death was 4-fold higher than expected (standardized mortality ratio, 4.2; 95% CI, 2.9-5.8). The risk of sudden cardiac death has declined significantly over time (hazard ratio [HR], 0.62 [95% CI, 0.44-0.88] for MIs that occurred between 1997 and 2005 compared with between 1979 and 1987; P = .03). The recurrent events of ischemia (n = 842), heart failure (n = 365), or both (n = 873) occurred in 2080 patients. After adjustment for baseline characteristics, recurrent ischemia was not associated with sudden cardiac death (HR, 1.26 [95% CI, 0.96-1.65]; P = .09), while heart failure markedly increased the risk of sudden cardiac death (HR, 4.20 [95% CI, 3.10-5.69]; P < .001).


CONCLUSIONS
The risk of sudden cardiac death following MI in community practice has declined significantly over the past 30 years. Sudden cardiac death is independently associated with heart failure but not with recurrent ischemia.
Adabag
A Selcuk
AS
Division of Cardiology, Veterans Affairs Medical Center, Minneapolis, Minnesota, USA.
Therneau
Terry M
TM
Gersh
Bernard J
BJ
Weston
Susan A
SA
Roger
Véronique L
VL
D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D016757:Death, Sudden, Cardiac / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D006333:Heart Failure / Q000150:complications; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D009203:Myocardial Infarction / Q000150:complications* / Q000401:mortality; D017202:Myocardial Ischemia / Q000150:complications; D012008:Recurrence; D012306:Risk