d o
t o r e g . c o m
Dr. Mete ALPASLAN
Amiodarone and the ECG
Last update: May 2020
Amiodarone
is a widely used antiarrhythmic drug which has mainly Class III antiarrhythmic effects.
ECG abnormalities that may be observed in patients under Amiodarone therapy
Sinus bradycardia
QT interval prolongation
Prolonged PR interval
Widening of the T wave
Prominence of the U wave
ECG abnormalities that may be observed in patients with Amiodarone overdose
Sinoatrial exit block
Sinus arrest
Torsades de pointes
Postoperative atrial fibrillation is a frequent complication of cardiac surgery. Oral and intravenous Amiodarone have been used to prevent postoperative atrial fibrillation in patients undergoing cardiac surgery. To decrease the side effects of Amiodarone therapy, local delivery of Amiodarone to the myocardium has been investigated. Two studies have reported that epicardial application of amiodarone-releasing adhesive hydrogel during cardiac surgery was effective in preventing postoperative atrial fibrillation. These studies (by Feng XD et al and Bockeria OL et al) showed that PR interval or QT interval prolongation was not observed after epicardial application of Amiodarone.
References
J Cardiovasc Transl Res 2020;13:191-198.
J Thorac Cardiovasc Surg 2014;148:939-943. (free full-text)
Chou's Electrocardiography in Clinical Practice. Adult and Pediatric. 5th ed. Philadelphia. WB Saunders. 2001.
Ann Intern Med 1994;121:529.
Am J Cardiol 1984;54:347.
Circulation 1983;67:45.
N Engl J Med 1981;305:539.
Br Heart J 1979;42:573.
Am J Cardiol 1976;38:934.
Am J Cardiol 1974;34:215.
ECG 1. The above ECG shows sinus bradycardia and prolonged PR interval.
The patient was under Amiodarone and Metoprolol therapy.
Click here for a more detailed ECG
ECG 2. The above ECG belongs to a 62 years-old man who had undergone coronary artery bypass graft operation 3 months ago.
He is under Amiodarone therapy. Prominent U waves are seen.
Click here for a more detailed ECG
ECG 3. The above ECG is from an 81 years-old man.
It was recorded after Amiodarone infusion for the treatment of ventricular tachycardia.
QT interval prolongation due to Amiodarone is seen.
Click here for a more detailed ECG
ECG 4. The rhythm tracing above is from the monitor recording of a 69 years-old woman.
She was receiving intravenous Amiodarone infusion to convert the recent-onset atrial fibrillation.
The tracing shows emergence of the sinus rhythm.
Click here for a more detailed ECG
ECG 5a. Atrial flutter with sawtooth appearence is seen in the above ECG.
Heart rate is about 150/min.
Dr. Veli Vefali has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 5b. After starting Amiodarone infusion, the degree of atrioventricular block increased.
Now, the ventricular rate is decreased and the heart rate is about 84/min.
Dr. Veli Vefali has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 6. The ECG above is from a 69 years-old man with coronary artery disease and heart failure.
He had previously undergone coronary artery bypass graft surgery.
His left ventricular Ejection Fraction was reported as 30% (low). He also has an ICD pacemaker.
The rhythm is atrial fibrillation. The ventricular rate is very low due to concomitant Amiodarone and Digoxin use.
Both Amiodarone and Digoxin decrease ventricular response during atrial fibrillation.
Click here for a more detailed ECG
ECG 7. The above ECG belongs to a 78 years-old man who had undergone coronary artery bypass surgery in the past.
Left bundle branch block is seen.
His ECHOcardiogram was normal: no valvular heart disease, no systolic heart failure.
He is under Amiodarone therapy.
Amiodarone therapy has resulted in PR interval prolongation, QT interval prolongation and bradycardia.
Click here for a more detailed ECG
ECG 8a. The ECG above belongs to a 66 years-old woman with coronary artery disease and mitral valve prosthesis.
She had undergone coronary artery bypass grafting operation and mitral valve replacement 2 weeks ago.
She had experienced inferoposterior wall myocardial infarction before the operation.
Now she has left ventricular systolic dysfunction with Ejection Fraction (EF) of 35%.
She is under Bisoprolol (beta blocker) therapy.
Her heart rate is 110/minute.
The rhythm is atrial flutter. The heart rate is low due to beta blocking effect of Bisoprolol.
Click here for a more detailed ECG
ECG 8b. The ECG above belongs to the same woman.
It was recorded 24 hours after the onset of intravenous Amiodarone infusion. Bisoprolol was stopped.
This ECG was recorded at a standard calibration of 10 mm/mV and at a paper speed of 25 mm/second.
Now, the heart rate is 92/minute. Amiodarone therapy decreases heart rate in atrial flutter.
Click here for a more detailed ECG
ECG 8c. The ECG above belongs to the same woman. It was recorded just before the ECG 8b.
This time, the calibration was set to 20 mm/mV to see the details clearly.
Her heart rate is 93/minute.
Seemingly P waves in lead V1 are in fact flutter waves.
Some flutter waves deform terminal portion of the QRS complexes, especially in lead V1.
The rhythm is atrial flutter (slowed by Amiodarone).
Amiodarone therapy decreases heart rate in atrial flutter.
Click here for a more detailed ECG
ECG 8d. The ECG above belongs to the same woman. It was recorded 9 days after the ECG 8c.
This time, the rhythm is sinus tachycardia with a heart rate of 104/minute.
Leads II and V1 clearly show P waves with normal PR interval.
Click here for a more detailed ECG
Amiodarone
is a widely used antiarrhythmic drug which has mainly Class III antiarrhythmic effects.
ECG abnormalities that may be observed in patients under Amiodarone therapy
Sinus bradycardia
QT interval prolongation
Prolonged PR interval
Widening of the T wave
Prominence of the U wave
ECG abnormalities that may be observed in patients with Amiodarone overdose
Sinoatrial exit block
Sinus arrest
Torsades de pointes
Postoperative atrial fibrillation is a frequent complication of cardiac surgery. Oral and intravenous Amiodarone have been used to prevent postoperative atrial fibrillation in patients undergoing cardiac surgery. To decrease the side effects of Amiodarone therapy, local delivery of Amiodarone to the myocardium has been investigated. Two studies have reported that epicardial application of amiodarone-releasing adhesive hydrogel during cardiac surgery was effective in preventing postoperative atrial fibrillation. These studies (by Feng XD et al and Bockeria OL et al) showed that PR interval or QT interval prolongation was not observed after epicardial application of Amiodarone.
References
J Cardiovasc Transl Res 2020;13:191-198.
J Thorac Cardiovasc Surg 2014;148:939-943. (free full-text)
Chou's Electrocardiography in Clinical Practice. Adult and Pediatric. 5th ed. Philadelphia. WB Saunders. 2001.
Ann Intern Med 1994;121:529.
Am J Cardiol 1984;54:347.
Circulation 1983;67:45.
N Engl J Med 1981;305:539.
Br Heart J 1979;42:573.
Am J Cardiol 1976;38:934.
Am J Cardiol 1974;34:215.
ECG 1. The above ECG shows sinus bradycardia and prolonged PR interval.
The patient was under Amiodarone and Metoprolol therapy.
Click here for a more detailed ECG
ECG 2. The above ECG belongs to a 62 years-old man who had undergone coronary artery bypass graft operation 3 months ago.
He is under Amiodarone therapy. Prominent U waves are seen.
Click here for a more detailed ECG
ECG 3. The above ECG is from an 81 years-old man.
It was recorded after Amiodarone infusion for the treatment of ventricular tachycardia.
QT interval prolongation due to Amiodarone is seen.
Click here for a more detailed ECG
ECG 4. The rhythm tracing above is from the monitor recording of a 69 years-old woman.
She was receiving intravenous Amiodarone infusion to convert the recent-onset atrial fibrillation.
The tracing shows emergence of the sinus rhythm.
Click here for a more detailed ECG
ECG 5a. Atrial flutter with sawtooth appearence is seen in the above ECG.
Heart rate is about 150/min.
Dr. Veli Vefali has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 5b. After starting Amiodarone infusion, the degree of atrioventricular block increased.
Now, the ventricular rate is decreased and the heart rate is about 84/min.
Dr. Veli Vefali has donated the above ECG to our website.
Click here for a more detailed ECG
ECG 6. The ECG above is from a 69 years-old man with coronary artery disease and heart failure.
He had previously undergone coronary artery bypass graft surgery.
His left ventricular Ejection Fraction was reported as 30% (low). He also has an ICD pacemaker.
The rhythm is atrial fibrillation. The ventricular rate is very low due to concomitant Amiodarone and Digoxin use.
Both Amiodarone and Digoxin decrease ventricular response during atrial fibrillation.
Click here for a more detailed ECG
ECG 7. The above ECG belongs to a 78 years-old man who had undergone coronary artery bypass surgery in the past.
Left bundle branch block is seen.
His ECHOcardiogram was normal: no valvular heart disease, no systolic heart failure.
He is under Amiodarone therapy.
Amiodarone therapy has resulted in PR interval prolongation, QT interval prolongation and bradycardia.
Click here for a more detailed ECG
ECG 8a. The ECG above belongs to a 66 years-old woman with coronary artery disease and mitral valve prosthesis.
She had undergone coronary artery bypass grafting operation and mitral valve replacement 2 weeks ago.
She had experienced inferoposterior wall myocardial infarction before the operation.
Now she has left ventricular systolic dysfunction with Ejection Fraction (EF) of 35%.
She is under Bisoprolol (beta blocker) therapy.
Her heart rate is 110/minute.
The rhythm is atrial flutter. The heart rate is low due to beta blocking effect of Bisoprolol.
Click here for a more detailed ECG
ECG 8b. The ECG above belongs to the same woman.
It was recorded 24 hours after the onset of intravenous Amiodarone infusion. Bisoprolol was stopped.
This ECG was recorded at a standard calibration of 10 mm/mV and at a paper speed of 25 mm/second.
Now, the heart rate is 92/minute. Amiodarone therapy decreases heart rate in atrial flutter.
Click here for a more detailed ECG
ECG 8c. The ECG above belongs to the same woman. It was recorded just before the ECG 8b.
This time, the calibration was set to 20 mm/mV to see the details clearly.
Her heart rate is 93/minute.
Seemingly P waves in lead V1 are in fact flutter waves.
Some flutter waves deform terminal portion of the QRS complexes, especially in lead V1.
The rhythm is atrial flutter (slowed by Amiodarone).
Amiodarone therapy decreases heart rate in atrial flutter.
Click here for a more detailed ECG
ECG 8d. The ECG above belongs to the same woman. It was recorded 9 days after the ECG 8c.
This time, the rhythm is sinus tachycardia with a heart rate of 104/minute.
Leads II and V1 clearly show P waves with normal PR interval.
Click here for a more detailed ECG