Myocardial Injury Induced by Radiofrequency and Low Energy Ablation: A Quantitative Study of CK Isoforms, CK‐MB, and Troponin‐T Concentrations

Abstract

We conducted a prospective, controlled study to investigate the use of CK-MB concentration and newer methods such as troponin-T concentration and CK isoforms, in the assessment of myocardial damage caused by radiofrequency current or low energy DC catheter ablation. The study population consisted of 3 consecutive patients who underwent low energy catheter ablation, 28 consecutive patients subjected to radiofrequency ablation, and 4 patients who were subjected to radiofrequency energy ablation but also had external DC shocks for cardioversion of atrial fibrillation that occurred during the procedure. The control group comprised eight subjects undergoing electrophysiological study. Prior to ablation and at 30 minutes, 1, 2, 6, and 12 hours following the procedure, serial blood samples were taken for measurement of troponin-T and CK-MB concentrations, and calculation of the MM3/MM1 and MB2/MB1 ratios. Troponin-T concentration was raised above normal in all patients subjected to low energy ablation and in all but two patients subjected to radiofrequency ablation. Only 42% of all patients subjected to ablation had at least one raised CK-MB concentration postablation. The MB2/MB1 ratio was raised in all but had at least one raised CK-MB concentration postablation. The MB2/MB1 ratio was raised in all but two patients following radiofrequency or low energy ablation but it was also abnormal in the preablation samples in nine patients. The MM3/MM1 ratio failed to detect myocardial damage in 71% of all patients. There was a statistically significant difference between the control and patient groups regarding all four indices of myocardial damage. Low energy ablation caused a significantly higher degree of myocardial damage compared with radiofrequency (RF); this effect could not be attributed to different numbers of total energy discharges. Our results indicate that catheter ablation, regardless of the mode of energy used, inflicts detectable injury upon the myocardium. This injury can be quantitated by using newer analytical techniques, such as serial, postablation measurements of troponin-T concentration.

Successful Radiofrequency Ablation in Patients With Previous Atrial Fibrillation Results in a Significant Decrease in Left Atrial Size

“…Previous studies have demonstrated that the extent of myocardial damage incurred by RF ablations can be quantified by using cardiospecific biochemical markers such as troponin T. 23,24 In the present study, the patients with persistent SR had significantly higher troponin T levels compared with patients who had recurrent AF after ablation, suggesting that "biochemical proof" of atrial debulking may play a role in the persistence of SR after catheter ablation of AF. Therefore, electric mass reduction could be considered an integral part of the EAA and may play an important role in its success.…”

Biomarkers of myocardial injury with different energy sources for atrial fibrillation catheter ablation

“…A lower cTn level is expected after RF of focal area with few RF lesions. RF ablation of more myocardial tissue in the atria, such as in PV isolation, is expected to have much higher cTn levels [10][11][12][20][21][22][23][24][25]. Previous clinical studies reported contrasting data, in the setting of AF ablation, on cardiac biomarkers levels after cryoballoon ablation compared to RF ablation [7,[13][14][15][16][17][18][19]26].…”

Sequential Evaluation of Left Ventricular Systolic and Diastolic Function After Radiofrequency Catheter Ablation

“…26) Several biochemical parameters have been validated in the diagnosis of this myocardial damage induced by RF ablation. 2,6) In this regard, we measured CKMB concentrations in all patients before and 8 hours after the procedure. Compared with before the procedure, the CKMB levels significantly increased after the RF ablation (P < 0.001).…”

“…5) Several biochemical parameters have also been validated in the diagnosis of this myocardial damage induced by RF ablation. 2,6) In patients with left ventricular dysfunction, long-term improvement of systolic and diastolic left ventricular function was seen after RF ablation of the atrioventricular junction for rate control of atrial fibrillation. 7,8) Likewise, a reversibility was also observed in left ventricular dysfunction after successful RF catheter ablation of reentrant tachycardia in which AV nodal conduction block was not created.…”