Prognostic Value of Very Low Plasma Concentrations of Troponin T in Patients With Stable Chronic Heart Failure

Abstract

Background-Circulating cardiac troponin T, a marker of cardiomyocyte injury, predicts adverse outcome in patients with heart failure (HF) but is detectable in only a small fraction of those with chronic stable HF. We assessed the prognostic value of circulating cardiac troponin T in patients with stable chronic HF with a traditional (cTnT) and a new precommercial highly sensitive assay (hsTnT). Methods and Results-Plasma troponin T was measured in 4053 patients with chronic HF enrolled in the Valsartan HeartFailure Trial (Val-HeFT). Troponin T was detectable in 10.4% of the population with the cTnT assay (detection limit Յ0.01 ng/mL) compared with 92.0% with the new hsTnT assay (Յ0.001 ng/mL). Patients with cTnT elevation or with hsTnT above the median (0.012 ng/mL) had more severe HF and worse outcome. In Cox proportional hazards models adjusting for clinical risk factors, cTnT was associated with death (780 events; hazard ratioϭ2. Key Words: heart failure Ⅲ natriuretic peptides Ⅲ prognosis Ⅲ troponin C ardiac troponins I and T (cTnT) are sensitive and specific markers of myocardial injury used routinely for the diagnosis of acute coronary syndromes. 1-5 Elevated troponin blood levels have been reported in several cohorts of patients with heart failure (HF), and the magnitude of elevation has been correlated with the severity of the disease and with adverse outcomes. 6 -16 Because of their high cardiac specificity, elevated troponins in patients with HF may suggest ongoing myocardial damage and may serve as a marker for the progression of HF. Measurement of troponin has been proposed since 1997 to monitor patients with HF. 17,18 The prevalence of elevated troponin T in the general population is Ͻ1% and is associated with underlying cardiovascular disease or high-risk phenotypes. 19 Editorial p 1217 Clinical Perspective p 1249The levels of cardiac troponins in HF are generally lower than those in patients with acute coronary syndromes and lack the characteristic rise and fall pattern. 4 Few reports exist on cTnT elevations in chronic stable HF. 6,8,16,20 Previous studies included more frequently patients with severe HF (New York Heart Association [NYHA] class III and IV) and/or with decompensated HF, recruited in a single center. 6,8,10,11,15,16 As expected, lesser severity of HF is associated with a larger fraction of patients with undetectable troponin. The commercial assays for troponins have sufficient sensitivity (0.01 ng/mL) for screening patients with suspected myocardial infarction 21 but may be inadequate for risk stratification of patients with stable chronic HF who may have levels below Methods Study Design and PatientsVal-HeFT was a randomized, placebo-controlled, double-blind, parallel-arm multicenter trial of 5010 patients with stable, symptomatic HF, who were on prescribed HF therapy. The patients had a left ventricular ejection fraction (LVEF) Ͻ40% and a left ventricular diameter in diastole adjusted for body surface area (LVIDD/BSA) Ն2.9 cm/m 2 . Results of the main trial have been published....

Elevated Cardiac Troponin T Predicts Adverse Outcomes in Hypertensive Patients

“…3,5,38) However, most studies of the prognostic value of cTnT in acute coronary syndrome, chronic heart failure and pulmonary embolism have found that the cTnT level at a single point is an independent predictor of future cardiac events. 2,4,[6][7][8]20,39) The rate of cTnT detected by the assay in the present study is very low in healthy adults. 17) Thus, we believe that elevated cTnT even at a single point has clinical significance.…”

“…cTnT is a sensitive marker for the detection of myocardial damage in patients with not only acute coronary syndrome but also with chronic heart failure [2][3][4][5][6][7][8] and pulmonary embolism. 20) Therefore, some hypertensive patients might have ongoing myocardial damage.…”

“…Recently, a newly developed high sensitivity cTnT assay has become available. Recent studies have shown that the high sensitivity cTnT assay has a prognostic value at concentrations that are undetectable using the conventional cTnT assay in patients with chronic heart failure 6) and was significantly associated with the incidence of cardio-vascular death and heart failure in patients with stable coronary artery disease. 34) Otsuka, et al 35) reported that high sensitivity cTnT was independently associated with systolic BP and LV hypertrophy in middle-aged men without overt cardiovascular disease.…”

“…Recent studies including ours have shown that ongoing myocardial damage detected as elevated cTnT levels can discriminate patients with chronic heart failure (CHF) at increased risk for future cardiac events. [2][3][4][5][6][7][8] HT is an important precursor of heart failure. Several experimental studies have shown that myocardial damage or apoptotic cardiomyocytes are associated with HT.…”

Usefulness of Serum Cardiac Troponins T and I to Predict Cardiac Molecular Changes and Cardiac Damage in Patients With Hypertrophic Cardiomyopathy

“…16) Recently, a highly sensitive commercial assay of cTnI or cTnT is being widely used for cardiac injury evaluation. Latini, et al 17) reported that, with a standard assay, cTnT was detectable in 10% of patients with chronic HF but that, using a new hs-cTnT assay (Roche Diagnostics), it was detectable in 92% of HF patients. In our study, serum hs-cTnT values of 23% of HCM patients remained below the lower detection limit of the assay (0.003 ng/mL).…”