Term
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Definition
| The technique of recording electrical potentials from the conduction system within the heart |
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Term
| Most common site for stimulation and recording |
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Definition
| Most common site for stimulation and recording is the high posterolateral wall at the junction of the SVC in the region of the SA node. (HRA) |
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Term
| The first functional contact with the myocardium |
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Definition
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Term
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Definition
•Platinum tip unipolar electrode catheter
•Woven dacron, single lumen with one end hole
•Used in pacing, blood sampling, intracardiac ECG, and detecting intracardiac shunts hydrogen ion studies. |
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Term
| The standard for temporary pacing electrodes |
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Definition
NBIH Bipolar Temporary Pacing Electrode
–Woven dacron, no lumen, two electrodes at the tip and 1 cm proximal.
–Used for temporary pacing and intracardiac EKG's. |
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Term
| With catheter placement why do we need surface ECGs? |
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Definition
–To determine morphology of induced arrhythmias
–To detect evidence of pre-excitation
–To find the earliest ventricular activity |
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Term
| What are the upper extremity vein sites for catheter placement? |
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Definition
•Left basilic vein
•Subclavian vein
•Internal jugular vein
–Safer and easier to use than left basilic vein |
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Term
| Which sites depolarizes the earliest in the right atrium? |
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Definition
–SVC-Atrial junction site depolarizes the earliest (50% of population)
–Midlateral RA (2-3 cm inferior from the HRA site) depolarizes earlier in the other 50%. |
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Term
| The left atrium is MOST commonly approached from where? |
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Definition
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Term
| most easily identified and reproducible site for stimulation and recording |
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Definition
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Term
| LV Access required for patients with what? |
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Definition
| Access required for patients with pre-excitation syndrome and ventricular tachyarrhythmia's for stimulation and recording |
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Term
| Advantageous to record bundle potential with several lead pairs using a tripolar catheter |
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Definition
–Distal-proximal
–Distal-middle |
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Term
| the initial portion of the His bundle originates in the? |
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Definition
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Term
| What should you do if the first pass proves unsuccessful in locating a bundle potential? |
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Definition
| the catheter is again passed into the ventricle and withdrawn with a slight different rotation (torque) to explore a different portion of the tricuspid ring |
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Term
| Primary reasons for doing EP study |
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Definition
•To assess conduction delays or blocks
•To evaluate and/or isolate the mechanism of SVT
•To evaluate and/or isolate the mechanism of VT
•Indications for patients with documented or suspected arrhythmias that require further study:
–Sinus node disease
–AV conduction delays or blocks
–Differentiate between SVT and VT |
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Term
| Most patients with sinus node disease - decision for pacemaker implant can be made on the basis of |
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Definition
| history and ambulatory monitoring. |
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Term
| Only definitive way to differentiate SVT with aberrancy (wide QRS complex tachycardia) from VT. |
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Definition
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Term
| can be reproduced in 90% of the patients using programmed stimulation. |
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Definition
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Term
| EPS is mandatory if the following is planned: |
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Definition
–Automatic implantable cardioverter defibrillator (AICD)
–Surgical therapy ablation
•Out-of-hospital cardiac arrest
–Assess condition of conduction system post arrest
–Determine cause of arrest
•Syncope
–Unexplained after full non-invasive evaluation |
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Term
| Contraindications for EP Study |
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Definition
•When acute factors make the findings unrepresentative of the patient’s usual state.
–Electrolyte imbalance
–Acute ischemia
–Drug toxicity
•Any patient with cardiac disease makes it likely that induced arrhythmias will be extremely difficult to terminate such as:
–Acute myocardial infarction (AMI)
–Unstable angina
–Class IV heart failure
–Aortic ostium (AO) stenosis |
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Term
| Risks and complications from cardiac catheterizations |
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Definition
–Thromboembolism
–Perforation
–Infection
–Arrhythmias |
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Term
| Risks and complications specifically associated with electrical stimulation |
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Definition
•Atrial fibrillation
–Atrial stimulation may induce a-fib and with patients with WPW, a rapid ventricular response may occur causing hemodynamic compromise which requires urgent cardioversion.
–Non-symptomatic usually converts on its own after a couple of hours.
•Ventricular stimulation studies may still be performed during atrial fibrillation.
–Ventricular tachycardia/fibrillation |
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Term
| What is the major risk associated with EPS requiring immediate cardioversion/defibrillation? |
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Definition
| Induction of unstable ventricular arrhythmias |
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Term
| Use of anticoagulation is needed if catheters are left in place for how long? |
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Definition
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Term
| Sinus node recovery time (SNRT) |
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Definition
| The longest pause from the last paced atrial depolarization to the first sinus return cycle at any paced cycle length |
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Term
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Definition
Is equal to the SNRT minus the patient's intrinsic sinus cycle length.
–Should be < 550 msec |
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Term
| Sinoatrial Conduction Time (SACT) |
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Definition
Measured as the interval between the pacemaker pre-potential on a sinus node electrogram and the onset of the rapid atrial deflection HRA electrogram.
–Validation of sinus node electrograms is difficult and some studies have indirect means of measurement.
–Typical value range is 45 – 125 msec. |
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Term
| a must prior to implanting antitachycardic pacemakers and defibrillators. |
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Definition
| Tissue refractoriness and conduction system evaluation data derived from EP studies |
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Term
| Indications for Ablations |
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Definition
•Presence of life-threatening arrhythmias
•Drug-refractory tachycardias which incorporate a bypass tract
•Presence of tachyarrhythmias incorporating a bypass tract in a young person facing a lifetime of expense and morbidity of drug therapy |
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Term
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Definition
| is used to restore normal electrical conduction by freezing tissue or heart pathways that interfere with the normal distribution of the heart’s electrical impulses. |
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Term
| A cryoablation catheter removes heat from the tissue to cool it to temperatures as low as |
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Definition
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Term
| Results in electrophysiologic changes in the arrhythmogenic tissue render it nonarrhythmogenic tissue. |
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Definition
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Term
| Radiofrequency ablation (RF) |
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Definition
| Use of alternating current resulting in thermal injury with coagulation necrosis and desiccation |
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Term
| Advantages ofRadiofrequency ablation (RF) |
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Definition
–Absence of barotrauma
–Absence of pain
–Lack of stimulation of muscles
–Control of focal injury
–Smaller lesions than with DC ablation |
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Term
| Two types of incremental pacing |
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Definition
-Decremental pacing
-Ramp pacing |
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Term
| Normal response to atrial pacing is what? |
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Definition
| for the A-H interval to gradually lengthen as the cycle length is decreased until A-V nodal block. |
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Term
| for the A-H interval to gradually lengthen as the cycle length is decreased until A-V nodal block. |
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Definition
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Term
| fulcrum of the conduction system |
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Definition
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Term
| Marks the end of the full recovery period, the zone during which conduction of the premature and basic drive impulses are identical. |
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Definition
| Relative Refractory Period (RRP) |
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Term
| Longest coupling interval between the basic drive and the premature impulse that fails to propagate through a cardiac tissue. |
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Definition
| Effective Refractory Period (ERP) |
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Term
| Minimum interval between two consecutively conducted impulses through a cardiac tissue. |
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Definition
| Functional Refractory Period (FRP) |
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Term
| Typical normal values for ERP include |
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Definition
–Atrial: 200 – 270 msec
–A-V node: 280 – 450 msec
–Ventricle: 200 – 270 msec |
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Term
| What is the normal value for P-A Interval? |
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Definition
Normal time 20 to 50 msec
•Prolongation is usually a result of atrial enlargement or atrial hypertrophy. |
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Term
| Used to measure the approximate AV conduction time |
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Definition
A-H Interval
Measured from the onset of the atrial spike on HBE to the onset of the His bundle spike |
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Term
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Definition
–Normal conduction time (in sinus rhythm) 45 to 140 msec
•Prolongation indicates disease of the AV node |
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Term
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Definition
–Normal interval 35 to 55 msec
–Prolongation represents bundle branch block that may require permanent pacing. |
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Term
| His bundle deflection duration |
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Definition
| 15 to 25 msec in duration, interposed between local atrial and ventricular deflections |
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Term
| Time of depolarization of the proximal bundle to the onset of ventricular depolarization ranges from 35 to 55 msec. |
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Definition
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Term
| His bundle deflection should be no less than _______ from the ventricular depolarization in adults. |
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Definition
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Term
| provides the strongest criteria validating the His bundle potential |
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Definition
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Term
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Definition
| Procedure used to identify the presence and type of Neurogenic syncope; in this lesson referred to as Tilt-Table Testing. |
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Term
| Neurogenic Syncope symptoms may include? |
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Definition
| •Symptoms may include nausea, weakness, pallor, a "sinking feeling," pressure in the epigastrium, diaphoresis, and a feeling of warmth. Yawning and sleepiness are not uncommon. |
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Term
| •Associated with specific circumstances (situational syncope), such as micturition, defecation, cough, or abrupt pain from a visceral or cutaneous site |
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Definition
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Term
| potential precipitating factors for Neurogenic Syncope |
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Definition
| Painful or emotional experiences, hot and humid weather conditions, relative dehydration, and a recent history of strenuous exertion are all potential precipitating factors. |
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Term
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Definition
| is diagnosed when a precipitous fall in blood pressure is accompanied by a reduction in heart rate (low 40s or lower). |
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Term
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Definition
| is hypotension not associated with decreased heart rate. |
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Term
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Definition
| is diagnosed by a gradual (not precipitous) fall in blood pressure without any significant change in heart rate. It eventually reaches levels associated with loss of consciousness (LOC). Patients with autonomic dysfunction also demonstrate an abnormal response to the Valsalva maneuver in that they do not exhibit blood pressure overshoot when the maneuver is terminated. |
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Term
| The duration of the tilt-table test is usually...? |
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Definition
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Term
| Medications that commonly contribute to syncope include (but are not limited to): |
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Definition
–Antihypertensives (all of them)
–Tricyclic antidepressants
–Phenothia/ine
–Quinidine/quinine
•Common clinical situation with the elderly patients |
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