Causes of Broad complex tachycardia
- Ventricular tachycardia is most concerning
- Atrial fibrillation with aberrant conduction (Bundle branch block)
- SVT with aberrant conduction (Bundle branch block)
- Atrial flutter with aberrant conduction (Bundle branch block)
- Sinus tachycardia with aberrant conduction (Bundle branch block)
- Ventricular tachycardia is defined as three or more ventricular complexes in succession at a rate greater than 100 bpm. Patients presenting with ventricular tachycardia often present with a regular heart rate between 100 and 250 bpm (HR below = 146 bpm), in which the QRS morphology is constant and abnormally wide (greater than 0.12 seconds).
- Frequently, these ECG's demonstrate AV dissociation in which the ventricular rate is greater than the atrial rate. P waves are frequently hidden within the broad ventricular complexes, although they can sometimes be identified as bumps or notches in the ventricular cycles.
- Although patients without heart disease may develop paroxysmal non-sustained ventricular tachycardia, chronic sustained VT is most commonly associated with coronary artery disease, dilated cardiomyopathy and prior myocardial infarction or severe heart disease.