Frequency and cause of cardiac troponin T elevation in chronic hemodialysis patients from study of cardiovascular magnetic resonance.
Cardiac troponin T level predicts a gradient risk for death in patients using hemodialysis. We used cardiovascular magnetic resonance (CMR) to determine whether an asymptomatic increase of troponin T in patients using hemodialysis is associated with subclinical myocardial infarction (MI). Twenty-six patients using long-term hemodialysis (49 +/- 12 years of age, 19 men, 8 diabetics) with left ventricular (LV) ejection fraction >40% and no known coronary artery disease were selected based on a low-risk troponin T level </=0.03 ng/ml (median 0.02, interquartile range 0.00 to 0.02, n = 13) and high-risk troponin T level >/=0.07 ng/ml (median 0.15, interquartile range 0.09 to 0.19, n = 13). All underwent CMR imaging for LV mass and for MI by late gadolinium enhancement. Between high- and low-risk patients using hemodialysis, there were no differences in age, gender, ethnicity, or diabetes mellitus. Of the high-risk patients, 3 (23%, 95% confidence interval [CI] 5 to 54) had MI by late gadolinium enhancement versus 0 (0%, 95% CI 0 to 25) low-risk patients (p = 0.22). A diffuse, midwall late gadolinium enhancement pattern was seen in 1 high-risk patient (8%) versus 0 low-risk patient (0%, 95% CI 0 to 25, p = 0.97). Height-adjusted LV mass and LV hypertrophy were not significantly different between high-risk (62 +/- 26 g/m(2.7), LV hypertrophy, n = 7, 54%) and low-risk (54 +/- 20 g/m(2.7), LV hypertrophy, n = 5, 39%) patients (p = 0.37 for LV mass, p = 0.69 for LV hypertrophy). In conclusion, MI detected by CMR is present in few patients on hemodialysis with high troponin T levels and absent in the setting of very low troponin T levels, suggesting that additional myocardial pathologies cause increased troponin T in patients using hemodialysis.
deFilippi
Christopher R
CR
Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA. cdefilip@medicine.umaryland.edu
Thorn
Eric M
EM
Aggarwal
Monica
M
Joy
Abel
A
Christenson
Robert H
RH
Duh
Show-Hong
SH
Jeudy
Jean
J
Beache
Garth
G
D003287:Contrast Media; D003430:Cross-Sectional Studies; D004452:Echocardiography; D005260:Female; D005682:Gadolinium; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000097:blood / Q000175:diagnosis; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis*; D009206:Myocardium / Q000473:pathology*; D006435:Renal Dialysis; D012307:Risk Factors; D013318:Stroke Volume / Q000502:physiology; D020107:Troponin T / Q000097:blood*
D003287:Contrast Media; D020107:Troponin T; D005682:Gadolinium