- Definition of V tach: - by definition, 4 or more
PVC's in a Row; - appears as wide
QRS usually with
Left B.B.B. pattern (as opposed to a narrow complex seen with
SVT); - may occurs short paroxysm or as sustained run w/ rate between 120-250 BPM;
- SVT vs VT - aberrant conduction (
SVT) is favored w/
Rt BBB shaped
QRS complexes at a frequency above 170/min; - AV dissociation during tachycardia implies ventricualr origin; -
ventricular tachycardia is usually regular, but alteration of R-R interval during Tachycardia may occur in both V.Tach &
SVT; -
QRS width of > 0.14 seconds favors V tach; - V. tach is also favored w/ Mono or Biphasic
Right Bundle Branch Block- Shaped
QRS complexes in lead V1; - an atrial impulse may break thru from above to stimulate - normal appearing
QRS complex during
VT; - if portion of
QRS is present = "Fusion Beat"; - If there is complete
QRS = "Capture Beat"; - presence of "captures" or "fusions" making the diagnosis of
VT; --------------------------
