title: Coronary microvascular dysfunction and diastolic load correlate with cardiac troponin T release measured by a highly sensitive assay in patients with nonischemic heart failure.
abstract: OBJECTIVE
  This study investigated factors associated with cardiac troponin T (cTnT) release from failing myocardium.
  
  
  BACKGROUND
  Persistent and modest elevation of serum cTnT is frequently observed in heart failure (HF) patients free of coronary artery disease, although the mechanisms underlying this finding remain unclear.
  
  
  METHODS
  We evaluated serum cTnT levels in the aortic root (Ao) and coronary sinus (CS) using a highly sensitive assay in 90 nonischemic HF patients and 47 non-HF patients. Transcardiac cTnT and plasma B-type natriuretic peptide (BNP) release were described as the differences between CS and Ao cTnT levels [ΔcTnT (CS-Ao)] and BNP levels [ΔBNP (CS-Ao)], respectively. Coronary flow reserve (CFR) was measured in 68 HF patients using an intracoronary Doppler guidewire.
  
  
  RESULTS
  ΔcTnT (CS-Ao) levels were available in 76 HF patients and 28 non-HF patients (84% vs. 60%; p = 0.001), and higher in HF patients than non-HF patients (p < 0.001). Among HF patients, log[ΔcTnT (CS-Ao)] correlated with log[ΔBNP (CS-Ao)] (r = 0.368, p = 0.001), pulmonary capillary wedge pressure (r = 0.253, p = 0.03) and left ventricular end-diastolic pressure (LVEDP) (r = 0.321, p = 0.005). Multivariate regression analysis identified LVEDP as an independent parameter that correlated with ΔcTnT (CS-Ao). ΔcTnT (CS-Ao) levels were available in 58 HF patients who were evaluated for CFR. Coronary microvascular dysfunction, diagnosed by CFR <2.0, was observed in 18 HF patients. ΔcTnT (CS-Ao) was higher in patients with coronary microvascular dysfunction (4.8 [2.0 to 8.1] ng/l) than those without (2.0 [1.2 to 4.6] ng/l; p = 0.04).
  
  
  CONCLUSIONS
  cTnT release from failing myocardium correlated with diastolic load and coronary microvascular dysfunction in nonischemic HF patients.
authors: Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan.
authors: Seiji
authors: S
authors: Takashio
authors: Megumi
authors: M
authors: Yamamuro
authors: Yasuhiro
authors: Y
authors: Izumiya
authors: Seigo
authors: S
authors: Sugiyama
authors: Sunao
authors: S
authors: Kojima
authors: Eiichiro
authors: E
authors: Yamamoto
authors: Kenichi
authors: K
authors: Tsujita
authors: Tomoko
authors: T
authors: Tanaka
authors: Shinji
authors: S
authors: Tayama
authors: Koichi
authors: K
authors: Kaikita
authors: Seiji
authors: S
authors: Hokimoto
authors: Hisao
authors: H
authors: Ogawa
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003326:Coronary Circulation / Q000502:physiology; D004452:Echocardiography / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D012016:Reference Values; D012044:Regression Analysis; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D013318:Stroke Volume; D015996:Survival Rate; D020107:Troponin T / Q000097:blood* / Q000378:metabolism
chemical_list: D015415:Biomarkers; D020107:Troponin T
keywords: Ao; CAD; CFR; CI; CMVD; CS; FV; IL; LVEDP; OR; TNF; aortic root; cTnT; cardiac troponin T; confidence interval; coronary artery disease; coronary flow reserve; coronary microvascular dysfunction; coronary sinus; femoral vain; heart failure; high-sensitivity C-reactive protein; highly-sensitive troponin T; hs-CRP; hs-TnT; interleukin; left ventricular end-diastolic pressure; natriuretic peptide; odds ratio; troponin; tumor necrosis factor; wall stress