Wide Bizarre QRS complexes (of supra ventricular origin) are often caused by
Often result from intraventricular conduction defect Typically a result of right or left bundle branch block
Ventricular Preexcitation Definition Causes May Produce/present on EKG how?
Premature depolarization of the ventricles Occurs when an impulse arising from a supraventricular site travels through abnormal accessory conduction pathways to the ventricles May produce: Wider than normal QRS complexes Abnormal slurring at its onset (called the delta wave)
Cardiac pacemaker induced QRS complexes
Generally ≥ 0.12 seconds in width and appear bizarre Preceding each pacemaker-induced QRS complex is a pacemaker spike
What are Premature Ventricular Complexes (PVC)?
Early beats that arise from the ventricles before SA node can fire
When does idioventricular rhythm occur?
Arises from the ventricles when stimuli from the SA node, AV junction fail to reach the ventricles or their rate falls to less than that of the ventricles.
May present as a wide QRS complex
True/False: Wide QRS complexes may be seen with ventricular tachycardia
How many PVCs in a row are considered VT?
3 or more in a row May come in bursts of 6 to10 complexes or be sustained
What is the HR range in sustained VT?
What is it called when you have for example 3 PVCs, then 3 regular, then 3 PVCs then 3 regular for example
Explain the presentation of torsades de points
Appears as a series of QRS complexes that rotate about the baseline between upright deflections and downward deflections This produces a "spindle-like" appearance of the ECG rhythm
True/False: Wide QRS complexes are seen in 3rd degree AV heart block
What do wide, large (bizarre looking) QRS complexes indicate about the ventricles?
The ventricles are likely being paced by a ventricular focus.
Ventricular fibrillation causes the heart muscle to quiver, instead of contracting and pumping blood throughout the body. what is considered the definitive treatment of vent. fib that must be delivered promptly?
Explain Ventricular Fibrillation on an EKG
Represents erratic firing of multiple sites in the ventricles On ECG monitor it looks like a chaotic, wavy line with no discernible waveforms
What is the 4th step in analyzing EKGs?
QRS complexes (0.06-0.12 sec)
What is the 1st step in analyzing EKGs?
What is the 2nd step in analyzing EKGs?
What is the 3rd step in analyzing EKGs?
P wave (0.06- 0.12 sec)
What is the 5th step in analyzing EKGs?
PR interval (0.12-0.20 sec)
Where do you start and end when measuring QRS complexes?
QRS complex starts where first wave of complex begins to move away from the baseline. It ends at the point where the last wave of the complex transitions into the ST segment.