Abstract 15293: Increased Level of Cardiac Troponin T is a Clue of Cardiac Amyloidosis in Patients With Myocardial Hypertrophy
Background: Cardiac amyloidosis (CA) is an important differential diagnosis in patients with myocardial hypertrophy. The precise diagnosis of CA requires endomyocardial biopsy to demonstrate amyloid deposition, but this procedure is relatively invasive and cannot be performed routinely. Therefore, it is important to increase pretest probability of CA in patients with myocardial hypertrophy by noninvasive modalities. Because it is well known that cardiac troponin level is elevated in patients with CA, we hypothesized that increased level of cardiac troponin T contributes to diagnosis of CA in patients with myocardial hypertrophy using high sensitive assay (hs-TnT).
Methods and Results: Among nonischemic patients with myocardial hypertrophy (interventricular septal thickness≧ 12 mm), hs-TnT level was measured in 28 CA patients (senile systemic amyloidosis: 13, AL amyloidosis: 14, familial amyloidosis: 1) proven amyloidosis pathologically and 29 non-CA patients proven by endomyocardial biopsy. It was significantly higher in CA patients than non-CA patients (0.075 [0.047-0.116] ng/ml vs. 0.013 [0.009-0.019] ng/ml; p<0.001: Figure). Receiver operating characteristic analysis selected 0.030 ng/ml as the best cutoff value of diagnosis for CA, with a sensitivity and specificity of 96% and 93%, respectively and area under the curve of 0.98 (95% confidence interval 0.94 to 1.00, p<0.001).
Conclusions: Increased level of hs-TnT (>0.030 ng/ml) is highly suggestive of CA in patients with myocardial hypertrophy. These patients need additional diagnostic approach for CA.
Author Disclosures: S. Takashio: None. M. Yamamuro: None. T. Anzai: None. H. Ogawa: None.
- © 2014 by American Heart Association, Inc.