Name that arrhythmia
A focal or localized atrial rhythm originating outside the sinus node, often showing a consistent atrial activation sequence
Atrial Tachycardia (AT)
A short PPI - TCL suggests the pacing site is closer to the tachycardia circuit
True (the smaller the difference between PPI and TCL, the less additional conduction time is required to reach and return from the reentrant circuit)
Name all 6 limb leads
I, II, III, AVR, AVL, AVF
What maneuver helps determine a tachycardia's circuit?
Entrainment
What interval is measured from the onset of the atrial electrogram to the onset of the His electrogram?
AH interval
A reentrant tachycardia involving the slow and fast pathways within or near the AV node.
AVNRT
PFA creates lesions by heating cardiac tissue
False (PFA uses electroporation and not thermal energy)
Describe what typical flutter may look like
"Sawtooth" flutter waves in II, III, and aVF
Regular atrial rate around 250-350 bpm
2:1 or 3:1 AV conduction
What medication may be used to reverse the effects of heparin?
Protamine
What interval represents conduction from the beginning of atrial activation to the beginning of ventricular activation?
PR Interval
This macro reentrant tachycardia does not require the CTI and may develop around atrial scar or a prior ablation line
Atypical Flutter
The AV node is the only electrical connection between the atria and ventricles
False (accessory pathways can provide an additional connection)
Why might someone get a cardiac ablation?
This pacing technique is used to determine whether block is present across an ablation line
Differential pacing
A tachycardia has a cycle length of 320ms. The PPI after entrainment is 370ms. What is the PPI - TCL?
50ms
An early ventricular beat originating from a ventricular focus rather than the normal conduction system
PVC
In typical atrial flutter, successful CTI ablation should result in bidirectional conduction block across the Cavo tricuspid isthmus
True (it depends on the CTI as part of its reentrant circuit and demonstrating block in both directions confirms that the CTI has been electrically interrupted and the flutter circuit can no longer conduct through the isthmus)
This protective beat occurs after a pause when the heart's normal "pacemaker" fails to fire, allowing a slower secondary "pacemaker" to take over
Escape beat
Why do we give adenosine when testing for entrance/exit block in the left atrium?
To challenge the isolation and look for dormant conduction that may not be apparent during baseline testing
During atrial pacing, the cycle length is gradually shortened until an atrial beat fails to conduct to the ventricle. What are you measuring?
AV Wenckebach cycle length
This abnormal conduction pathway bypasses the AV node and can serve as the retrograde or antegrade limb of a reentrant tachycardia
Accessory Pathway
Increasing RF power always results in a deeper and safer lesion
False (excessive power can increase complications such as steam pops, tissue damage, and in other serious cases, coagulum formation)
Describe a junctional escape rhythm
Originates in an AV Junction automaticity, may escape overdrive suppression to become an active pacemaker
Becomes the dominant pacemaker of the heart at a rate ranging from 40-60 bpm
Conducts mainly to ventricles, producing a series of lone QRS complexes that are narrow, and the P wave is within it which is why you can't see it
What are the STANDARD diagnostic catheters utilized for a basic EP study?
HRA, His, RVA, and CS
What is the longest S1-S2 interval that fails to produce an atrial depolarization?
AERP (Atrial Effective Refractory Period)