Efficacy and Safety of Outpatient Clinic-based Elective External Electrical Cardioversion in Patients with Atrial Fibrillation

Evaluation of Changes in Cardiac Troponin I Levels After Direct Current Cardioversion in Patients With Atrial Fibrillation

INTRODUCTION

Direct current cardioversion (DCCV) of atrial fibrillation (AF) is a procedure used to restore normal heart rhythm. Cardiac biomarkers, such as cardiac troponin I (cTnI), are elevated in situations where injury-myocardial cell necrosis is induced.

AIM

The aim of the present study was to investigate the change in cTnI levels, i.e., whether a myocardial injury is present, in patients with AF whose elective treatment was synchronized DCCV via a biphasic defibrillator.

METHODS

The study sample included 59 patients who underwent synchronized DCCV for AF reversion. Measurement of cTnI before and after DCCV (one, three, and six hours) was performed by blood sampling and subsequent assay.

RESULTS

It was observed that the value of cTnI did not change (<0.1 ng/mL) after DCCV at the measurement time points (one, three, and six hours). In addition, the value of cTnI remained constant (<0.1 ng/mL) in relation to the energy delivered, before DCCV and after DCCV (one, three, and six hours). However, it was found that there was a correlation between the outcome (AF reversion or not) and the energy used (joules).

CONCLUSIONS

Synchronized DCCV with a biphasic defibrillator did not cause myocardial injury in any of the patients, as there was no change in cTnI values before and after DCCV.

The Impact of Right Atrial Size to Predict Success of Direct Current Cardioversion in Patients With Persistent Atrial Fibrillation

BACKGROUND AND OBJECTIVES

The prognostic implication of right atrial (RA) and left atrial (LA) size for an immediate success of direct current cardioversion (DCCV) in atrial fibrillation (AF) remains unclear. This study aimed to compare RA and LA size for the prediction of DCCV success.

METHODS

Between 2012 and 2018, 734 consecutive outpatients were screened for our prospective registry. Each eligible patient received a medical history, blood analysis, and transthoracic echocardiography with a focus on indexed RA (iRA) area and LA volume (iLAV) prior to DCCV with up to three biphasic shocks (200-300-360 J) or additional administration of amiodarone or flecainide to restore sinus rhythm.

RESULTS

We enrolled 589 patients, and DCCV was in 89% (n=523) successful. Mean age was 68 ± 10 years, and 40% (n=234) had New York heart association class >II. A prevalence of the male sex (64%, n=376) and of persistent AF (86%, n=505) was observed. Although DCCV success was associated with female sex (odds ratio [OR], 1.88; 95% confidence interval [CI], 1.06-3.65), with absence of coronary heart disease and normal left ventricular function (OR, 2.24; 95% CI, 1.26-4.25), with short AF duration (OR, 1.93; 95% CI, 1.05-4.04) in univariable regression, only iRA area remained a stable and independent predictor of DCCV success (OR, 0.27; 95% CI, 0.12-0.69; area under the curve 0.71), but not iLAV size (OR, 1.16; 95% CI, 1.05-1.56) in multivariable analysis.

CONCLUSIONS

iRA area is superior to iLAV for the prediction of immediate DCCV success in AF.