TDBBB can be diagnosed with use of an electrocardiogram (ECG) which will "trace" the electrical activity of the heart, providing an overall view of the hearts electrical system. Typically, TDBBB will be evident on an ECG and manifest as a prolongation of the QRS complex (a QRS complex completion time that exceeds 120ms), notching or slurring of the R wave, or the absence of Q waves should the TDBBB affect the left ventricle.
Tachycardia-dependent bundle branch block
Permanent junctional reciprocating tachycardia
AV nodal reentrant tachycardia
Second-degree atrioventricular block
Third-degree atrioventricular block
Junctional ectopic tachycardia
First-degree atrioventricular block
Atrioventricular reentrant tachycardia