Prevalence, kinetic changes and possible reasons of elevated cardiac troponin T in patients with AV nodal re-entrant tachycardia.

Background: Elevated cardiac troponin (cTn) has been reported to occur with AVNRT. Little is known about prevalence, kinetic changes, and possible reasons of increased cTn.

Methods: We evaluated 139 consecutive patients presenting with AVNRT to the emergency department between 2006 and 2010. Cardiac troponin T (cTnT) was measured serially at baseline, after three and six hours. Patients were evaluated for the presence of structural heart disease or CAD. Troponin was defined as elevated if a value exceeded the lower limit of detection (10 ng/l) using the fourth generation cTnT, or if the value > 99 th percentile (14 ng/l) using the new highly sensitive cTn assay.

Results: A cTnT > LLD (n = 29) or > 99 th percentile (n = 16) was found in 45 patients (32.4%) within the initial six hours after hospitalization. All patients were symptomatic with palpitations, chest discomfort or dyspnea. A complete cardiac evaluation was carried out, including coronary angiography in 32 patients demonstrating an underlying structural heart disease or CAD in 18 cases (56%). Significant CAD was detected in 16 cases. 8 cases required PCI during hospitalization. Elevated cTnT was seen in patients with and without structural heart disease.

Conclusions: AVNRT is a possible reason for elevated cTnT, even in the absence of relevant structural heart disease or CAD.