Serum levels of high-sensitivity troponin T: a novel marker for cardiac remodeling in hypertrophic cardiomyopathy

Background: Hypertrophic cardiomyopathy (HCM) is characterized by inappropriate hypertrophy, small-vessel coronary artery disease, myocyte disarray, and increased interstitial fibrosis. High-sensitivity troponin T (hs-TnT) could be a reliable indicator of myocardial remodeling, a proposed prognostic marker in HCM. Therefore we hypothesized that increased hs-TnT levels are related to different variables associated with myocardial remodeling, such as the presence of fibrosis assessed with cardiac magnetic resonance imaging (MRI).

Methods and results: We included 95 hemodynamically stable HCM patients, 72 male, aged 45.7 ± 14.2 years, and 45 healthy control subjects with similar age and gender. A complete history and clinical examination was performed, including 12-lead electrocardiogram (ECG), echocardiography, 24-hour ECG-Holter monitoring, symptom-limited treadmill exercise test, and late gadolinium enhancement in cardiac MRI. Risk factors for sudden death were evaluated. A blinded cardiac MRI was performed with late gadolinium enhancement study. Serum hs-TnT levels were assayed. A high proportion (42%) of hemodynamically stable patients studied showed increased levels of hs-TnT. The hs-TnT levels were raised in patients with severe dyspnea: New York Heart Association (NYHA) functional class ≥3 (P = .020), outflow obstruction (P = .013), systolic dysfunction (P = .037), abnormal blood pressure response (P = .036), and presence of gadolinium enhancement (P = .021). The hs-TnT levels correlated positively with the maximum left ventricular wall thickness (r = 0.47; P < .001), left atrial diameter (r = 0.36, P = .014), and outflow gradient (r = 0.28; P = .008).

Conclusions: A high proportion of hemodynamically stable patients show increased levels of hs-TnT. We observed that raised hs-TnT serum levels are associated with different conditions related to the severity of the disease.