This 59-year-old woman with known dilated cardiomyopathy and history of tachyarrhythmias has suddenly developed severe palpitation and  dyspnea:

• Ventricular tachycardia, rate 128/min
• There is evidence of AV dissociation
• The atrial rhythm is atrial tachycardia, rate 180/min

Comment: Further investigation of this patient demonstrated recurrent episodes of ventricular tachycardia, often preceded by (and/or associated with) runs of atrial tachycardia.