Sudden Death in a Patient with Myotonic Dystrophy Type I

Risk factor for sudden cardiac death:

(1) prolonged His-ventricular interval (>= 70 milliseconds)

(2) sustained ventricular tachyarrhythmia

(3) atrial flutter

(4) hypertension

(5) PR interval >= 240 ms

(6) QRS interval >= 120 ms

(7) palpitations

(8) right bundle branch block, left bundle branch block, or bifascicular block

(9) family history of sudden death

(10) syncope

The presence of a prolonged His-ventricular interval cannot be reliably predicted from the ECG and electrophysiologic testing is required. A patient with a prolonged His-ventricular interval should be considered for prophylactic pacemaker insertion.

Other causes of sudden death need to be excluded.