Myocardial ischemia, cardiac troponin, and long-term survival of high-cardiac risk critically ill intensive care unit patients.
OBJECTIVE
To determine the incidence and association of myocardial ischemia with troponin elevation and survival in high-cardiac-risk intensive care patients.


METHODS
Prospective observational study.


METHODS
Intensive care unit of a tertiary hospital.


METHODS
One-hundred one general intensive care unit patients having a history of coronary artery disease or at least two risk factors for coronary artery disease.


METHODS
Continuous 12-lead electrocardiographic monitoring with on-line ST-trend analysis, daily cardiac troponin measurements, clinical and physiologic assessment, and up to 2-yr follow-up for survival.


RESULTS
During 8,988 hrs or a mean +/- sd of 95 +/- 85 hrs/patient of continuous 12-lead electrocardiographic monitoring, 21 patients (21%) had ischemic ST-segment changes, characterized in most (19) by ST depression and lasting >60 mins in 15 (71.4%). Of the 38 patients (38%) with troponin elevation, myocardial infarction was clinically suspected in four and myocardial ischemia on continuous 12-lead electrocardiographic monitoring was observed in 14 (36.8%). Fourteen (66.7%) of the patients with ischemic ST changes and 12 (75%) of those with prolonged (>60 mins) ischemia had troponin elevation. The sensitivity, specificity, and positive and negative predictive values of prolonged (>60 mins) ischemia predicting troponin elevation were 31.6%, 95.2%, 80.0%, and 69.8%, respectively. Prolonged (>60 mins) ischemia was significantly associated with troponin elevation by both univariate and multivariate analyses (odds ratio = 9.0; p = .008). Acute Physiology and Chronic Health Evaluation II score, renal failure, and the use of norepinephrine also independently predicted troponin elevation. Troponin but not ischemia predicted increased 1-month, 6-month, and 2-yr mortality (odds ratio = 6.0, 3.2, and 2.99, respectively; p < .001).


CONCLUSIONS
Silent ischemia is strongly associated with troponin elevation in high-cardiac-risk intensive care unit patients, and troponin elevation predicts both early and late mortality.
Landesberg
Giora
G
Department of Anesthesiology and Critical Care Medicine, Hadassah Medical Center, Jerusalem, Israel.
Vesselov
Yellena
Y
Einav
Sharon
S
Goodman
Sergei
S
Sprung
Charles L
CL
Weissman
Charles
C
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers; D005260:Female; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data; D007557:Israel / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000097:blood / Q000517:prevention & control; D017202:Myocardial Ischemia / Q000097:blood / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012306:Risk; D012680:Sensitivity and Specificity; D015996:Survival Rate; D014336:Troponin / Q000097:blood*
D015415:Biomarkers; D014336:Troponin