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t o r e g . c o m
Dr. Mete ALPASLAN
Flecainide and the ECG
Flecainide
is a Class Ic antiarrhythmic agent.
is a sodium channel blocker causing rate-dependent slowing of phase 0 of the fast sodium channel.
can also inhibit the slow calcium channel in higher doses.
has a narrow therapeutic index (0.2-1.0 mcg/mL) which eases the possibility of drug toxicity.
Electrophysiological effects of Flecainide
Flecainide slows conduction in all cardiac fibers.
Flecainide increases conduction times in the atria, AV node, His-Purkinje system, and ventricles.
This results in prolongation of the PR and QRS intervals on the ECG.
During Flecainide toxicity, supraventricular rhythms may present with bizarre, wide QRS complexes with
either right or left bundle branch block resulting in a misdiagnosis of ventricular tachycardia.
References (Click on the below references to see sample ECGs)
Cardiovasc Toxicol 2017;17(3):260-266
Circulation 2017;136(8):773-775
Ann Pediatr Cardiol 2017;10(3):288-292
Proc (Bayl Univ Med Cent) 2018;31(3):328-330
J Postgrad Med 2017;63(4):265-267
Indian Pacing Electrophysiol J 2019;19(2):75-78
Crit Pathw Cardiol 2017;16(1):42-45
ECG 1a. The ECG above belongs to a 76 years-old man.
He has ingested 900 mg Flecainide in 24 hours for symptomatic paroxysmal atrial fibrillation.
Bizarre, wide QRS complexes are seen.
Is the rhythm ventricular tachycardia? Would you cardiovert this rhythm?
Dr Ganesh Venkataraman has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 1b. The ECG above belongs to the same man.
It was recorded after the onset of sodium bicarbonate infusion.
Partial improvement of ST elevation is seen.
Dr Ganesh Venkataraman has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 1c. The ECG above belongs to the same man.
It was recorded after sodium bicarbonate infusion.
The rhythm is atrial flutter. ST segment elevation improved significantly.
This patient underwent cardioversion for the treatment of atrial flutter.
Dr Ganesh Venkataraman has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 1d. The ECG above belongs to the same man.
It was recorded after cardioversion for atrial flutter.
The rhythm is sinus now.
ST segment elevation or wide, bizarre QRS complexes are not seen.
Dr Ganesh Venkataraman has donated the above ECG to our website.
Click here for a more detailed ECG
is a Class Ic antiarrhythmic agent.
is a sodium channel blocker causing rate-dependent slowing of phase 0 of the fast sodium channel.
can also inhibit the slow calcium channel in higher doses.
has a narrow therapeutic index (0.2-1.0 mcg/mL) which eases the possibility of drug toxicity.
Electrophysiological effects of Flecainide
Flecainide slows conduction in all cardiac fibers.
Flecainide increases conduction times in the atria, AV node, His-Purkinje system, and ventricles.
This results in prolongation of the PR and QRS intervals on the ECG.
During Flecainide toxicity, supraventricular rhythms may present with bizarre, wide QRS complexes with
either right or left bundle branch block resulting in a misdiagnosis of ventricular tachycardia.
References (Click on the below references to see sample ECGs)
Cardiovasc Toxicol 2017;17(3):260-266
Circulation 2017;136(8):773-775
Ann Pediatr Cardiol 2017;10(3):288-292
Proc (Bayl Univ Med Cent) 2018;31(3):328-330
J Postgrad Med 2017;63(4):265-267
Indian Pacing Electrophysiol J 2019;19(2):75-78
Crit Pathw Cardiol 2017;16(1):42-45
ECG 1a. The ECG above belongs to a 76 years-old man.
He has ingested 900 mg Flecainide in 24 hours for symptomatic paroxysmal atrial fibrillation.
Bizarre, wide QRS complexes are seen.
Is the rhythm ventricular tachycardia? Would you cardiovert this rhythm?
Dr Ganesh Venkataraman has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 1b. The ECG above belongs to the same man.
It was recorded after the onset of sodium bicarbonate infusion.
Partial improvement of ST elevation is seen.
Dr Ganesh Venkataraman has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 1c. The ECG above belongs to the same man.
It was recorded after sodium bicarbonate infusion.
The rhythm is atrial flutter. ST segment elevation improved significantly.
This patient underwent cardioversion for the treatment of atrial flutter.
Dr Ganesh Venkataraman has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 1d. The ECG above belongs to the same man.
It was recorded after cardioversion for atrial flutter.
The rhythm is sinus now.
ST segment elevation or wide, bizarre QRS complexes are not seen.
Dr Ganesh Venkataraman has donated the above ECG to our website.
Click here for a more detailed ECG