Safety of out-of-hospital initiation of flecainide in patients with atrial and ventricular arrhythmias and structurally normal heart

Aim. This study aimed at investigating the safety of out-of-hospital initiation of flecainide in patients presenting with atrial or ventricular arrhythmias and structurally normal heart. Methods. Patients were followed 1 week, 1 month and 2 months after drug initiation either in person or through phone interviews and were asked to report symptoms suggestive of sustained arrhythmia, syncope, aborted sudden death and/or emergency room (ER) visits. QRS duration and QTc intervals were measured in a 12-lead ECG at each follow up. Patients were asked to fill out a treatment satisfaction questionnaire for medication (TSQM), four weeks after drug initiation. Results. The mean patient age was 48.5 ± 15.7 years, 36 patients (52%) were females. The most frequent presenting arrhythmia was premature ventricular contractions in 34 (45.3%) patients followed by paroxysmal atrial fibrillation in 22 (29.3%) patients. There was a significant increase in the mean QRS duration (89.9 ± 6.8 msec vs 91.1±7 msec, P <0.001) and the mean QTc interval (417.4 ±10.6 msec vs 418 ± 10.4 msec, P = 0.025) at 1 week compared to baseline. Only one patient (1.3%) had a clinically significant (more than 25%) increase in the QRS duration requiring drug discontinuation. There was no reported life-threatening ventricular arrhythmia, syncope, ER visits or aborted sudden cardiac death. There was 6.7% incidence of cardiac adverse events including conduction system abnormalities and atrial flutter, 4% of patients experienced non-resolving extracardiac manifestations. The overall drug discontinuation rate was 10.7%. The mean TSQM score for effectiveness domain was 70.4 ± 23.8 while the mean of the side effects domain was 94.3 ± 14.6, that of convenience domain was 65.2 ± 10.5 and that of global satisfaction was 72.8 ± 21.8. Conclusion. Out-of-hospital initiation of flecainide is safe and thus feasible, there was no reported documented or suspected life-threatening ventricular arrhythmias. Cardiac and extracardiac adverse events requiring drug discontinuation was effectively detected through clinical and ECG outpatient follow up.