The incidence of abnormal ECG findings in myotonic dystrophy is reported to be around 50%.

  The incidence of ventricular arrhythmias and sudden cardiac death is also increased in this disease.



ECG abnormalities that may be seen in patients with myotonic dystrophy

  First degree atrioventricular (AV) block

  Bundle branch block, fascicular block, intraventricular conduction disturbance

  Pathological Q waves

  Atrial fibrillation, atrial flutter

  Ventricular tachycardia

  Brugada pattern

  Ventricular fibrillation




References

  Turk Kardiyol Dern Ars 2009;37:337-40.

  West J Med 1990;153:24-7.

  Eur J Neurol 2011,18:191-4.

  N Engl J Med 2008;358:2688-97.





ECG 1. The ECG above belongs to a patient with myotonic dystrophy type 1. Heart rate is 52/minute and there is first degree
AV block (prolonged PR interval).

Dr. Karim Wahbi has donated this ECG to our website.

Click here for a more detailed ECG





ECG 2. Another patient with myotonic dystrophy type 1. The ryhthm is sinus. There is right bundle branch block.

Dr. Karim Wahbi has donated this ECG to our website.

Click here for a more detailed ECG





ECG 3. Another patient with myotonic dystrophy type 1. The rhythm is atrial flutter. Also, the patient has cardiac pacemaker
which gives
spike when heart rate decreases to 60/minute.

Dr. Karim Wahbi has donated this ECG to our website.

Click here for a more detailed ECG