Troponin levels after cardiac electrophysiology procedures: review of the literature.
Cardiac-specific Troponins (cTn) I and T have become markers of choice for myocardial injury. We reviewed the literature in order to understand the expected postprocedure cTn rise after electrophysiology procedures. A total of 34 studies and 1,608 patients were included. After external monophasic cardioversion, seven of 442 patients (1.6%) had minimal increase in cTnI (0.1-0.9 ng/mL), and only one of 368 (0.3%) had increase in cTnT (0.11 ng/mL). After internal cardioversion, 17 of 105 (16%) had increase in cTnI (0.7-2.4 ng/mL) but only three (2.9%) were above the cutoff for myocardial infarction (MI) (1.5 ng/mL). During implantable cardioverter-defibrillator (ICD) installation with a mean of 2-7 ICD shocks, 12 of 74 (16%) patients had cTnI >or=1.5 ng/mL (range 1.7-5.5 ng/mL) and 20 of 64 (32%) had cTnT >or=0.1 ng/mL (range 0.26-6.46 ng/mL) considered in the range of clinical MI. Radio frequency ablation (RFA) (n = 496) resulted in significant cTn elevation in 25-100% of patients with ventricular > atrial and linear > focal lesions. Average postprocedure peak cTnI ranged from 0.13 to 6 ng/mL (median: 2.36 ng/mL, max: 15 ng/mL) and cTnT 0.2 to 2.41 ng/mL (median: 0.44 ng/mL, max: 9 ng/mL). Early cTn peak at 2-8 hours was noted after RFA. External cardioversion should not cause a significant increase in cTn; RFA and ICD implantation with shocks often result in an increase in cTn. Interpretation of these markers can be difficult if acute coronary syndrome is suspected in the postprocedure period.