Cardiac high-sensitivity troponin T measurement: a layer of complexity in managing haemodialysis patients.
OBJECTIVE
To determine: (i) the proportion of stable asymptomatic haemodialysis patients with elevated troponin; (ii) stability of troponin values after dialysis and over a 2-week interval; and (iii) whether high-sensitivity troponin T (hsTnT) was associated with higher prevalence of cardiovascular risk factors or cardiovascular disease in these patients.


METHODS
We measured hsTnT and the fourth generation troponin I before and after dialysis in 103 stable in-centre haemodialysis patients without ischaemic symptoms. Patients were divided into quartiles to test for associations with established cardiovascular risk factors or disease.


RESULTS
hsTnT was above the 99th percentile for the general population in 99% of haemodialysis patients compared with only 13% elevation for the troponin I assay (P < 0.001). Median pre-dialysis hsTnT concentrations were unchanged after a 2-week interval (69 vs 69 ng/L, P = 0.55) but fell slightly immediately following dialysis (69 vs 61 ng/L, P < 0.001). Established coronary artery disease (59% vs 22%), peripheral vascular disease (38% vs 4%) and diabetes (18% vs 7%) were more prevalent (P < 0.05) in those in the highest quartile for hsTnT compared with those in the lowest quartile.


CONCLUSIONS
Almost all in-centre haemodialysis patients have elevated troponin T in their baseline stable state and this appears unchanged over a 2-week interval. Such a high rate of baseline elevation of hsTnT may lead to confusion in managing acute coronary syndrome in this group of patients, particularly when symptoms are atypical. We recommend that if Troponin I assay is unavailable then baseline hsTnT concentrations are measured periodically in all haemodialysis patients.
Departments of Renal Medicine, Prince of Wales Hospital, University of New South Wales, Sydney, NSW, Australia.
Timothy J
TJ
Pianta
Andrea R
AR
Horvath
Vivienne M
VM
Ellis
Rina
R
Leonetti
Christine
C
Moffat
Elizabeth A
EA
Josland
Mark A
MA
Brown
D000368:Aged; D058070:Asymptomatic Diseases; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D015897:Comorbidity; D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000097:blood / Q000453:epidemiology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009517:New South Wales / Q000453:epidemiology; D011237:Predictive Value of Tests; D015995:Prevalence; D006435:Renal Dialysis / Q000009:adverse effects; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D019210:Troponin I / Q000097:blood; D020107:Troponin T / Q000097:blood*; D015854:Up-Regulation
D015415:Biomarkers; C545568:TNNT2 protein, human; D019210:Troponin I; D020107:Troponin T