Abstract 10291: Predictive Values of N-Terminal Pro-B-Type Natriuretic Peptide and Cardiac Troponin I for Myocardial Fibrosis in Hypertrophic Obstructive Cardiomyopathy
Background: Myocardial fibrosis, as a hallmark of hypertrophic cardiomyopathy (HCM), can be detected by late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR). The combination of high-sensitivity cardiac troponin T (hs-cTnT) and B-type natriuretic peptide (BNP) has been suggested useful in detecting myocardial fibrosis in patients with non-obstructive HCM. However, the values of those biomarkers to predict myocardial fibrosis in hypertrophic obstructive cardiomyopathy (HOCM) remain unclear.
Hypothesis: We assessed the hypothesis that circulating levels of N-Terminal Pro-B-Type Natriuretic Peptide (NT-proBNP) and cardiac troponin I (cTnI) may predict LGE in patients with HOCM.
Methods: Patients with HOCM (n=163; age=47.2 ± 10.8, [range 20 to 71] years; 38.7% females) underwent peripheral venous sampling to determine concentrations of NT-proBNP and cTnI. Contrast-enhanced CMR was performed to identify and quantify myocardial fibrosis. We evaluated the relation between LGE and levels of NT-pro BNP and cTnI.
Results: LGE was detected in 120 of 163 patients (73.6%), and involved 31.6 ± 14.5% of left ventricle (range 2.9% to 73.5%). All participants had left ventricular outflow tract obstruction (LVOT gradient at rest, 78.7 ± 32.5 mmHg). Patients with LGE had significantly higher levels of NT-proBNP and cTnI than those without LGE (1386.2 [904.6 - 2340.8] vs. 866.6 [707.2 - 1875.2] pmol/L, P=0.003; 0.024 [0.010 - 0.049] vs. 0.010 [0.005 - 0.021] ng/ml, P<0.001, respectively). The extent of LGE was positively correlated with log cTnI (r=0.371, P<0.001) and log NT-proBNP (r=0.211, P=0.007). On multivariable analysis, log cTnI and log NT-proBNP were independent predictors of the presence of LGE (OR=3.916, P=0.010; OR=16.6, P=0.014, respectively). According to receiver operating characteristic curve analysis, combined measurements of NT-proBNP level ≥867.0 pmol/L and/or cTnI ≥0.025ng/ml indicated good diagnostic performance for the presence of LGE, with specificity of 92% or sensitivity of 90%.
Conclusions: Both NT-proBNP and cTnI are useful for identifying myocardial fibrosis, respectively. Combined measurements of these biomarkers further improve their values in detecting myocardial fibrosis in patients with HOCM.
- myocardial fibrosis
- Hypertrophic Obstructive Cardiomyopathy
- aminoterminal pro-B-type natriuretic peptide
- cardiac troponin I
- late gadolinium enhancement
Author Disclosures: C. Zhang: None. R. Liu: None. J. Yuan: None. J. Cui: None. F. Hu: None. W. Yang: None. Y. Zhang: None. Y. Chen: None. S. Qiao: None.
- © 2015 by American Heart Association, Inc.