Differentiation of atrial fibrillation progression phenotypes using Troponin T

Electro-anatomical remodeling in atrial fibrillation (AF) is associated with disease initiation and progression. Troponin T (TropT) - a specific biomarker for myocardial damage - is associated with AF incidence. However, its association with AF progression is understudied. The aim of the current analysis was to investigate the association between TropT and AF progression phenotypes: persistent AF and left atrial low voltage areas (LVAs).

Patients undergoing first AF ablation were included into analyses. LVAs were determined using high-density maps and defined as <0.5 mV. Blood samples from femoral vein were collected before catheter ablation. The analysis of TropT serum concentrations was performed using a high-sensitive assay from Roche Diagnostics. Biomarkers, clinical, anthropometric and echocardiographic data were compared with healthy individuals from the epidemiological cohort.

The study included 824 healthy individuals without overt cardiovascular disease (54 ± 10 years, 40% males) from epidemiological cohort and 241 AF patients (64 ± 11 years, 59% males, 59% persistent AF, 27% LVAs). Patients with AF had higher TropT levels and larger left atrium (LA), while healthy individuals had better renal function and ejection fraction (all p < 0.001). In clinical cohort, there were significant differences between TropT levels according to AF progression groups: paroxysmal AF without/with LVAs (n = 86/12), persistent AF without/with LVAs (n = 90/53): means 7.3, 12.9, 8.4, 11.3 pg/ml, p < 0.001, respectively. Similar findings were observed for LA and renal function (all p < 0.001). On ROC analysis, TropT significantly predicted LVAs (AUC 0.675, 95%CI 0.598-0.752, p < 0.001) in AF patients.

TropT may be useful to differentiate AF progression phenotypes.