B P7 C61 Approach to the Patient with Cardiac Arrhythmias Flashcards
The presence of regular cannon A waves in the jugular venous pulse would be consistent with 1:1 retrograde ventriculoatrial activation are seen in this type of tachycardias
JT
AVRT
AVNRT
VT
Physical examination features of AV dissociation, such as
1.
2.
3.
- Intermittent “cannon” A waves, indicative of right atrial contraction against a closed tricuspid valve
- Variable intensity of the S1
- Variable peak SBP
The _________________ and ________________ during the physical examination can be useful to interrupt arrhythmias sensitive to autonomic tone or identify the patient with a hypersensitive carotid sinus reflex.
Valsalva maneuver
Carotid sinus massage (CSM)
The most definitive responses to CSM are ___________________, as may be observed in AVRT, AVNRT, sinus node reentry, adenosine-sensitive AT, and idiopathic RVOT tachycardia.
Tachycardia termination
CSM generally does not affect reentrant ______________ or junctional tachycardias
Ventricular
During wide-QRS tachycardias with a 1:1 relationship between the P waves and QRS complexes, vagal influence can terminate or slow a supraventricular tachycardia (SVT) that depends on the AV node for perpetuation; on the other hand, vagal effects on the AV node can transiently block retrograde conduction and thus establish the diagnosis of VT by demonstrating AV dissociation
__________________ the awareness of the heartbeat that may be caused by a rapid heart rate, irregularities in heart rhythm, or an increase in the force of cardiac contraction, as occurs with a post–extrasystolic beat;
Palpitations
The ventricular systole that ends the compensatory pause is often responsible for the actual palpitation, the result of a more forceful contraction from prolonged _________________ or increased motion of the heart in the chest.
Ventricular filling
_____________________ constitute the most common causes of palpitations
PAC or PVC
Low-risk features of palpitations include:
- Isolated palpitations not induced by exercise
- The absence of structural heart disease or symptoms such as syncope or chest pain
- No family history of SCD
- Normal 12-lead ECG
Commonly referred to as “fainting” or “passing out,” is a tranient, self-limited loss of consciousness and posture resulting from a drop in blood pressure with cerebral hypoperfusion
Syncope
When caused by a cardiac arrhythmia, the onset of syncope is _________ and the duration is usually _________, with or without a preceding aura, and it is ________ typically followed by a postictal confusional state.
Rapid
Brief
Not followed by postictal state
____________ does not begin with or anticipate the syncope
Seizure
Syncope with early seizure activity is frequently caused by epilepsy, whereas later seizure activity is more likely caused by a cardiac arrhythmia with cerebral hypoperfusion.
Criteria for immediate evaluation of syncope
Structural heart disease
HF
Significant LV dysfunction or hypertrophy
Prior MI
Clinical features
Exertional syncope
Syncope while supine
Palpitations associated with syncope
Family history of SCD
ECG features
VT
Bifascicular block
IVCD
Sinus bradycardia, SA block
Preexcited QRS complex
Prolonged or short QT
Brugada pattern on ECG
T wave inversion or late potentials in the right precordial leads
Significant comorbidities
Anemia
Electrolyte imbalance
The most common type of reflex syncope
Neurocardiogenic
SCD caused by cardiac arrhythmias is most often the result of _________ or _____
VT
VF
In well-adjudicated cases, _____ is the most common finding in SCD and can be the first and last manifestation
Coronary heart disease (CHD)
Up to ___% of cases of SCD occur in patients with some form of structural heart disease, such as CHD, cardiomyopathy, or congenital heart disease.
80%
Other cardiac causes of SCD, referred to as “autopsy negative,” include primary electrical diseases such as _____.
LQTS
Brugada syndrome
Catecholaminergic polymorphic ventricular tachycardia (CPVT)
Idiopathic ventricular fibrillation (IVF)
Wolff-Parkinson-White (WPW) syndrome
___________, ____________, ___________ may precipitate cardiac arrest in the setting of a variety of structural heart diseases, arrhythmogenic cardiomyopathy (arrhythmogenic right ventricular cardiomyopathy/dysplasia, ARVC/D), and primary electrical diseases such as LQTS (types 1 and 2) and CPVT.
Exercise
Emotional upset
Stress
Exercise, emotional upset, or stress may precipitate cardiac arrest in the setting of a variety of _____.
Structural heart diseases
Arrhythmogenic cardiomyopathy (ARVC/D)
Primary electrical diseases: LQTS (types 1 and 2) and CPVT
SCD in LQTS3 or Brugada syndrome is more likely to occur at ________ or ________.
Rest
Sleep
Fever is a common precipitant of the characteristic ECG abnormality and arrhythmias in _______________.
Brugada syndrome
Give ECG abnormalities
WPW syndrome
LQTS/SQTS
Brugada syndrome
ARVC/D
Delta wave
Prolonged/short QT interval
Right precordial ST segment abnormalities
Epsilon waves
In a stable patient, if P waves are not clearly visible, the administration of _____ while running a rhythm strip may cause transient AV block and either terminate the tachycardia or allow discernment of P waves and diagnosis of the arrhythmia
Adenosine by rapid intravenous bolus (6 mg followed by 12 mg if no response to the first dose)
___________________ may be particularly useful in the evaluation of patients who experience symptoms with exertion
Exercise electrocardiographic stress testing
A _____ after the end of exercise (delay in return to baseline) is associated with a worse CV prognosis, as is a rapid resting heart rate.
Persistent elevation in heart rate
_____ beats of nonsustained VT can occur in normal subjects, especially elderly persons, and its occurrence nei- ther implicates ischemia or other forms of heart disease nor predicts
increased CV morbidity or mortality
3-6 beats
Ventricular ectopy occurs in about half of patients with CAD, generally appearing more reproducibly and at lower heart rates (<___ beats/min) than in healthy individuals and often in the early recovery period.
Frequent PVCs (>____per minute), polymorphic PVCs, and VT are more likely to occur in patients with CAD.
< 130 bpm
> 10/min
In patients with Brugada syndrome, significant ST-segment elevation with coving of the ST segment during the _____ phase predicts arrhythmic events during follow-up.
Recovery phase
The fundamental diagnostic principle in managing patients with an undocumented cardiac rhythm disturbance is to _____
Record the ECG during a symptomatic episode and establish a causal relation between the arrhythmia and symptoms
From _____% of patients experience a symptom during a 24-hour recording; in _____% the complaint is caused by an arrhythmia
25-50%: symptoms
2-15%: arrhythmia
Give possible diagnoses for wide complex tachycardia
VT
SVT wiht aberrancy
Preexcited tachycardia
ECG findings that favor VT
1.
2.
3.
- AV dissociation
- Fusion beats, capture beats
- Tachycardia beats identical to PVCs during sinus rhythm
________________ is most useful in patients with frequent (daily or more often) symptoms.
Holter monitoring is most useful in patients with frequent (daily or more often) symptoms.
Significant rhythm disturbances are uncommon in healthy young persons. _____ can be observed and are not necessarily abnormal.
Sinus bradycardia with HR of 35-40 beats/min
Sinus arrhythmia with pauses > 3 seconds
Sinoatrial exit block
Type I (Wenckebach) second-degree AV block (often during sleep)
Wandering atrial pacemaker
Junctional escape complexes
PACs
PVCs
Apple watch: Sensitivity of __% and specificity __% in identifying patients with silent atrial fibrillation
Sensitivity: 87%
Specificity: 97%
_____________ are indicated when symptoms occur less frequently (e.g., several episodes per month), and because the monitors are typically patient activated, and well-suited for correlating symptoms with rhythm disturbances.
Event recorders
However, frequent PVCs (>__% of the total) have been shown to produce a cardiomyopathy and heart failure in some people, which can be reversed following elimination of the PVCs. Most patients with ischemic heart disease, particularly after MI, exhibit PVCs when they are monitored for 24 hours.
> 15%
The frequency of PVCs progressively increases during the first several weeks and then decreases at about __ months after infarction.
6 months
_____ PVCs are associated with a two- to five- fold increased risk for cardiac or sudden death in patients after MI, but treating these PVCs may not improve the prognosis. Recent data indicate that _____ of PVCs after MI may improve previously depressed ventricular function
Frequent and complex PVCs
Ablation
_____________________ are typically used for the evaluation of suspected serious arrhythmias that occur infrequently and cannot be provoked at diagnostic EPS.
Implantable monitors or insertable loop recorders (ILRs)
An ILR, a single-lead ECG monitoring device placed subcutaneously at approximately the level of the anterior second rib, monitors the cardiac rhythm for as long as 24 to 36 months.
________ variability is used to evaluate vagal and sympathetic influences on the sinus node (inferring that the same activity is also occurring in the ventricles) and to identify patients at risk for a CV event or death.
Heart rate variability
R-R variability predicts all-cause mortality after MI, as does left ventricular ejection fraction or nonsustained VT
Measure of reflex vagal control of the heart
Heart rate turbulence
Abnormal heart rate turbulence is a strong independent predictor of mortality in patients with CAD and dilated cardiomyopathy.
Reflection of heterogeneity in refractoriness and conduction velocity, which is a hallmark of reentrant arrhythmias.
- QRS and QT dispersion
- T wave abnormalities
Beat-to-beat alternation in the amplitude or morphology of the ECG recording of ventricular repolarization, the ST segment, and the T wave.
T wave alternans
It has been found in conditions favoring the development of ventricular tachyarrhythmias, such as ischemia and LQTS, and in patients with ventricular arrhythmias. A positive T wave alternans test result has been associated with a worse arrhythmic prognosis in various disorders, including ischemic heart disease and nonischemic cardiomyopathy
Method for recording cardiac electrical activity at the skin surface and spatially integrating it with imaging data (currently, cardiac CT scanning).
Electrocardiographic imaging
Useful in the evaluation of patients without structural heart disease and recurrent syncope in whom there is suspicion that exaggerated vagal tone producing cardioinhibitory and/or vasodepressor responses
Tilt-table testing (TTT)
TTT has been suggested as a useful tool in the diagnosis of and therapy for _____
- Recurrent idiopathic vertigo
- Chronic fatigue syndrome
- Recurrent TIA
- Repeated falls of unknown etiology in elderly patients without much evidence
Relative contraindications of TTT
- Severe CAD with proximal coronary stenoses
- Known severe CVD
- Severe mitral stenosis
- LVOTO (e.g., aortic stenosis)
Patients are placed on a tilt table in the supine position and tilted upright to a maximum of ______ degrees for 20 to 45 minutes or longer if necessary.
60 to 80 degrees
_______ is administered as a bolus or infusion, may provoke syncope in patients whose initial upright TTT result shows no abnormalities or, after a few minutes of tilt, may shorten the time needed to produce a positive response on the test.
Isoproterenol
An initial intravenous isoproterenol dose of 1 μg/min can be increased in 0.5-μg/min steps until symptoms occur or a maximum of 4 μg/min is given
Isoprotproterenol induces a vasodepressor response in upright susceptible patients (decrease in heart rate and blood pressure along with nearsyncope or syncope).
Tilt-table test (TTT) results are positive in _____ of patients susceptible to neurally mediated syncope.They are reproducible in approximately 80% of patients but have a _____% false-positive response rate.A positive test result is more meaningful when it reproduces symptoms that have occurred spontaneously.
2/3 to 3/4
10-15% false positive response rate
Exaggerated activation of a central reflex in response to TTT produces a stereotypic response of an initial increase in ______________, followed by __________ in blood pressure and then a reduction in heart rate characteristic of neurally mediated hypotension
Increase Heart rate, Drop in BP
Reduction in HR
POTS is another aberrant variant of a neurocardiogenic reflex characterized by the inability to tolerate the upright posture and a dramatic increase (>_____ beats/min) in heart rate (>120 beats/min) within 10 minutes of assuming an upright posture
HR increase of > 30 bpm to > 120bpm within 10 mins of assuming an upright posture
Identify
Normal response
A normal response is an early, slight drop in BP with a compensatory increase in HR mediated by the autonomic nervous system.
Identify
Vasodepessor
Pure vasodepressor response is a relatively sudden drop in BP without a marked change in HR,
Identify
Cardioinhibitory
Pure cardioinhibitory response shows a sudden decrease in HR without a change in BP
Identify
Mixed
Mixed response shows decreases in both HR and BP.
Identify
Autonomic failure
Progressive fall in BP is not counteracted by an increase in HR
Identify
Postural tcahycardia
In POTS, an exaggerated increase in HR is seen.
This helps to define the mechanism of an arrhythmia, to deliver cathe ablative treatment, and to determine the etiology of symptoms that may be caused by an arrhythmia (e.g., syncope, palpitations)
EPS
The indications for EPS fall into several broad categories:
(1) Define the mechanism of an arrhythmia
(2) Deliver catheter-based ablative treatment
(3) Determine the etiology of symptoms that may be caused by an arrhythmia (e.g., syncope, palpitations)
Assessment of AV conduction at rest is done by p tioning electrodes along the septal leaflet of the tricuspid valve and measuring the ________________
Atrial-His interval (an estimate of AV nodal c tion time; normally, 60 to 125 milliseconds)
____________ measure of infranodal conduction; normally, 35 to 55 milliseconds
His-ventricular (H-V) interval
EP studies are performed diagnostically to _____.
Provide information about the type of clinical rhythm disturbance and insight into its electrophysiologic mechanism
EPS are used therapeutically to _____.
(1) Terminate a tachycardia by electrical stimulation or electroshock
(2) To evaluate the effects of therapy by determining whether a particular intervention modifies or prevents electrical induction of a tachycardia or whether an electrical device properly senses and terminates an induced tachyarrhythmia
(3) To ablate myocardium involved in the tachycardia and prevent further episodes
EPS have also been used prognostically to _____.
Identify patients at risk for SCD
In patients with AV block, the _____ usually dictates the clinical course of the patient and whether a pacemaker is needed
Site of block
In general, the site of AV block can be determined from analysis of the surface ECG. When the site of block cannot be deter- mined from such an analysis and when knowing the site of block is imperative for management of the patient, an invasive EPS is indicated. Candidates include _____.
(1) Symptomatic patients in whom His-Purkinje block is suspected but not established
(2) Patients with 2nd- or 3rd- degree AV block, for whom information about the site of block or its mechanism may help direct therapy or assess prognosis
(3) Patients suspected of having concealed His bundle extrasystoles
A ___________________(>55 msec) is associated with a greater likelihood of the development of a complete AV block (but typically the rate of progression is slow, 2% to 3% annually) and for having structural heart disease and a higher mortality
Prolonged H-V interval
The finding of very long H-V intervals (_____ msec) identifies patients at increased risk for the development of AV block
> 80 to 90 msec
During an EPS, atrial pacing is used to uncover abnormal His-Purkinje conduction. A positive response is _____.
Provocation of distal His block during 1:1 AV nodal conduction at rates of 135 beats/min or less
An EPS is indicated in patients with an intraventricular conduction disturbance with _____, including with prolonged ECG monitoring.
Symptoms (syncope or presyncope) that appear to be related to a bradyarrhythmia when no other cause of symptoms is identified,
An EPS is usually effective at initiating VT and SVT when these tachyarrhythmias have occurred spontaneously. Particularly for VT, programmed stimulation is used in a systematic attempt to induce the arrhythmia. Short bursts of _____ are followed by single ventricular extra- stimuli at varying coupling intervals, and eventually two or three extrastimuli are added.
Fixed rate ventricular pacing (e.g., eight beats at 100 to 150 beats/min,corresponding to a pacing cycle length of 600 to 400 msec)
Carotid sinus pressure that results in _____ exposes the presence of a hypersensitive carotid sinus reflex.
Several seconds of complete asystole or AV block and reproduces the patient’s usual symptoms
_____can be used to evaluate the effects of autonomic tone on sinus node automaticity and sinoatrial conduction time (SACT).
Neurohumoral agents
Adenosine
Stress testing
Sinus node recovery time (SNRT) is a technique that can be useful for evaluating sinus node function. Atrial pacing is initiated at a _____. The interval between the last paced high right atrial response and the first spontaneous (sinus) high right atrial response after termination of pacing is measured to determine SNRT
Fixed rate faster than the sinus rate for 30 to 60 seconds, after which is it abruptly terminated
Because the spontaneous sinus rate influences SNRT, the value is corrected by subtracting the spontaneous sinus node cycle length (before pacing) from the SNRT. This value, the corrected SNRT (CSNRT), is generally shorter than _____ milliseconds.
< 525 msec
A prolonged ___________ has been found in patients suspected of having sinus node dysfunction.
Corrected sinus node recovery time (CSNRT)
A prolonged CSNRT has been found in patients suspected of having sinus node dysfunction. After cessation of pacing, the first return sinus cycle can be normal but can be followed by _____ (a strong indicator of sinus node dysfunction).
Secondary pauses
SACT can be estimated by simple pacing techniques based on the assumptions that _____.
(1) conduction times into and out of the sinus node are equal
(2) no depression of sinus node automaticity occurs, and
(3) the pacemaker site does not shift after premature stimulation
In patients with tachycardias, an EPS can be used to _____.
(1) Diagnose the arrhythmia
(2) Determine and deliver therapy
(3) Establish the anatomic sites involved in the tachycardia
(4) Identify patients at high risk for the development of serious arrhythmias
(5) Gain insight into the mechanisms responsible for the arrhythmia
An SVT is recognized electrophysiologically by an H-V interval _____.
H-V interval equaling or exceeding that recorded during a normal sinus rhythm
During VT, the H-V interval is _____, or the His deflection cannot be recorded clearly because of superimposition of the larger ventricular electrogram.
Shorter than normal
Only two situations exist in which a consistently short H-V interval occurs:
- During retrograde activation of the His bundle from activation originating in the ventricle (i.e., PVC, ventricular pacing, or VT)
- During AV conduction over an accessory pathway (preexcitation syndrome).
Atrial pacing at rates exceeding the tachycardia rate can demonstrate the ventricular origin of a wide-QRS tachycardia by _____.
(1) Producing fusion and capture beats
(2) Normalization of the H-V interval
The only VT that exhibits an H-V interval equal to or slightly exceeding the normal sinus H-V interval is _____, but His activation will be in the retrograde direction.
Bundle branch reentry
An EPS should be considered for the following circumstances:
An EPS should be considered for the following circumstances:
(1) in patients who have symptomatic, recurrent, or drug-resistant supraventricular or ventricular tachyarrhythmias to help select optimal therapy
(2) in patients with tachyarrhythmias occurring too infrequently to permit adequate diagnostic or therapeutic assessment
(3) for differentiation of SVT and aberrant conduction from VT
(4) whenever nonpharmacologic therapy, such as the use of electrical devices, catheter ablation, or surgery, is contemplated
(5) in patients surviving an episode of cardiac arrest occurring more than 48 hours after acute MI or without evidence of an acute Q wave MI in an effort to establish a mechanism
(6) for assessment of the risk for sustained VT in patients with a previous MI, ejection fraction of 0.3 to 0.4, no evidence of heart failure, and nonsustained VT
In general, EPS is not indicated in patients with ______ and _________.
LQTS
TdP
_____ is the most common application of EPS in patients with tachycardia.
The process of initiation and termination of SVT or VT with programmed electrical stimulation to establish precise diagnoses and help select sites for catheter ablation
The three common arrhythmic causes of syncope are sinus node dysfunction, AV block, and tachyarrhythmias.
Of the three,_______________ are most reliably evaluated in the electrophysiology laboratory, followed by sinus node abnormalities and His-Purkinje block.
Tachyarrhythmias
Patients with a single episode of syncope and no evidence of structural heart disease, as well as those with a nondiagnostic EPS, have a low incidence of sudden death and an _____% remission rate over the ensuing 10 years.
80%
Syncopal patients considered for an EPS are those whose spells remain undiagnosed despite general, neurologic, and noninvasive cardiac evaluation, particularly if the patient has structural heart disease. The diagnostic yield is approximately __% in that group but only 12% in patients without structural heart disease.
70%
An EPS is indicated in patients with palpitations who have had a _____.
(1) Pulse documented by medical personnel to be inappropriately rapid or slow without an electrocardiographic recording
(2) Those suspected of having clinically significant arrhythmias without electrocardiographic documentation
In patients with syncope or palpitations, the sensitivity of EPS may be low but can be increased at the expense of specificity. For example, _____ can increase the likelihood of induction of ventricular arrhythmias by precipitating nonclinical ventricular tachyarrhythmias, such as nonsustained polymorphic VT or VF.
(1) More aggressive pacing techniques (e.g., use of three or four premature stimuli)
(2) Administration of drugs (e.g., isoproterenol)
(3) Left ventricular pacing
However, induction of _____ is almost never an artifact of stimulation, no matter how intense. Initiation of these arrhythmias in patients who have not had known spontaneous episodes of these tachycardias is uncommon and provides important information; for example, the induced tachyarrhythmia may be clinically significant and responsible for the patient’s symptoms.
Sustained SVT (e.g., AVNRT, AVRT)
OR
Monomorphic VT
The risks associated with undergoing only an EPS are small. _____can occur, each with less than a 1/500 incidence; the addition of ther- apeutic maneuvers (e.g., ablation) to the procedure increases the incidence of complications.
Myocardial perforation with cardiac tamponade
Pseudoaneurysms at arterial access sites
Provocation of nonclinical arrhythmias
With the increasing use of extensive ablation in the left atrium to treat AF, an increase in systemic _____ complications has been observed, as have _____
Thromboembolic complications
Pericardial effusion and tamponade
Valve damage
Phrenic nerve injury
In addition pericardial approaches (subxyphoid and anterior) to epicardial VT ablation can rarely be associated with _____.
Pericardial bleeding
RV puncture
Very rarely the need for cardiac surgery
_____ is a method whereby potentials recorded directly from the heart are spatially depicted as a function of time in an integrated manner.
Cardiac mapping
Conditions amenable to the cardiac mapping approach include _____.
Accessory pathways associated with WPW syndrome
Slow or fast pathways in AVNRT
AV node–His bun- dle ablation
Sites of origin of focal AT and VTs
Isolated pathways essential for the maintenance of reentrant ATs or VTs
Various substrates responsible for episodes of AF
Mapping can also be used to delineate the anatomic course of the _____ to avoid injury during catheter ablation or open heart surgery for repair of congenital heart disease.
His bundle and phrenic nerve
_____ is a technique in which pacing is performed at putative sites from which arrhythmias arise (a focus) or exit (reentrant circuit). The greater the degree of “match” in QRS complexes (for VT) or intracardiac activation sequences (for ATs), the more likely that the paced site may be an appropriate site for ablation
Pace mapping
Holter monitors (24 to 48 hours) are appropriate for episodes that occur at least _____.
Daily
Event recorders (30 to 60 days) for episodes that occur at least _____.
Monthly
Implantable loop recorders inserted subcutaneously can record bipolar ECG signals for up to _____ months
36 months
The ACC/AHA statement on clinical competence recommended that trainees interpret at least ___ ambulatory electrocardiograms under supervision to acquire minimal competence in this technology. A minimum of ___ test interpretations per year was recommended to maintain competence.
150
25/year
ACC/AHA 1999 Guidelines on Ambulatory Electrocardiography for Assessment of Symptoms and Arrhythmias
Class I recommendation for: Assessment of symptoms possibly related to rhythm disturbances
Patients with unexplained syncope, near-syncope, or episodic dizziness in whom the cause is not obvious
Patients with unexplained recurrent palpitation
ACC/AHA 1999 Guidelines on Ambulatory Electrocardiography for Assessment of Symptoms and Arrhythmias
Class I recommendation for: Assessment of antiarrhythmic therapy
To assess antiarrhythmic drug response in individuals in whom the baseline frequency of arrhythmia has been characterized as reproducible and of sufficient frequency to permit analysis
The only class I (clearly appropriate) indication for EPS in chronic IVCD is _____
Symptomatic patients for whom the cause of symptoms is not known
Class I indications for EPS in narrow and wide complex tachycardia include _____.
Patients with recurrent tachycardia for whom data from testing may help clinicians choose among drug therapy, catheter ablation, pacing, and surgery.
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Specific Electrocardiographic Abnormalities
Class I recommendation for: Evaluation of sinus node function
Symptomatic patients in whom sinus node dysfunction is suspected as the cause of symptoms, but a causal relationship between an arrhythmia and the symptoms has not been established after appropriate evaluation
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Specific Electrocardiographic Abnormalities
Class I recommendation for: Acquired AV block
Symptomatic patients in whom His-Purkinje block, suspected as a cause of symptoms, has not been established
Patients with second- or third- degree AV block treated with a pacemaker who remain symptomatic and in whom another arrhythmia is suspected as a cause of the symptoms
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Specific Electrocardiographic Abnormalities
Class I recommendation for: Chronic intraventricular conduction delay
Symptomatic patients in whom the cause of symptoms is not known
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Specific Electrocardiographic Abnormalities
Class I recommendation for: Narrow-QRS tachycardia (QRS complex <0.12 s)
Patients with frequent or poorly tolerated episodes
of tachycardia who do not adequately respond to drug therapy and for whom information about the site of origin, mechanism, and electrophysiologic properties of pathways of the tachycardia is essential for choosing appropriate therapy (e.g., drugs, catheter ablation, pacing, or surgery)
Patients who prefer ablative therapy to pharmacologic treatment
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Specific Electrocardiographic Abnormalities
Class I recommendation for: Wide-complex tachycardias
Patients with wide–QRS complex tachycardia in whom the correct diagnosis is unclear after analysis of available ECG tracings and for whom knowledge of the correct diagnosis is necessary for care
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Specific Electrocardiographic Abnormalities
Class I recommendation for: Prolonged–QT interval
syndrome
NONE
Class II:
Identification of proarrhythmic effect of a drug in patients experiencing sustained VT or cardiac arrest while receiving the drug
Patients who have equivocal abnormalities in QT interval duration or T-U wave configuration, along with syncope or symptomatic arrhythmias, in whom the effects of catecholamine may unmask a distinct QT abnormality
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Specific Electrocardiographic Abnormalities
Class I recommendation for: Wolff-Parkinson- White
syndrome
Patients being evaluated for catheter ablation or surgical ablation of an accessory pathway
Patients with ventricular preexcitation who have survived cardiac arrest or who have unexplained syncope
Symptomatic patients in whom determination of the mechanism of arrhythmia or knowledge of the electrophysiologic properties of the accessory pathway and normal conduction system would help in determining appropriate therapy
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Specific Electrocardiographic Abnormalities
Class I recommendation for: Premature ventricular complexes (PVCs), couplets, and nonsustained VT
NONE
Class II:
Patients with other risk factors for future arrhythmic events, such as a low ejection fraction, positive signal-averaged electrocardiogram, and nonsustained VT on ambulatory ECG recordings in whom EPS will be used for further risk assessment and for guiding therapy in patients with inducible VT
Patients with highly symptomatic, uniform- morphology PVCs, couplets, and nonsustained VT who are considered potential candidates for catheter ablation
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Clinical Syndromes
Class I recommendation for: Unexplained syncope
Patients with suspected structural heart disease and syncope
that remain unexplained after appropriate evaluation
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Clinical Syndromes
Class I recommendation for: Survivors of cardiac arrest
Patients surviving cardiac arrest without evidence of acute Q wave MI
Patients surviving cardiac arrest occurring more than 48 hr after acute phase of MI in the absence of recurrent ischemic events
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Evaluation of Clinical Syndromes
Class I recommendation for: Unexplained palpitations
Patients with palpitations who have their pulse rate documented by medical personnel as inappropriately rapid and in whom ECG recordings fail to document the cause of the palpitations
Patients with palpitations preceding a syncopal episode
ACC/AHA 1999 Guidelines on Ambulatory Electrocardiography for Assessment of Pacemaker and Implantable Cardioverter-Defibrillator (ICD) Function
Class I Recommanedations
Evaluation of frequent symptoms of palpitations, syncope, or near-syncope to assess device function, to exclude myopotential inhibition and pacemaker mediated tachycardia, and to assist in the programming of enhanced features, such as rate responsivity and automatic mode switching
Evaluation of suspected component failure or malfunction when device interrogation is not definitive in establishing a diagnosis
To assess response to adjunctive pharmacologic therapy in patients receiving frequent ICD therapy
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Therapeutic Intervention
Class I recommendations for: Guidance of drug therapy
Patients with sustained VT or cardiac arrest, especially those with prior MI
Patients with AVNRT, AV reentrant tachycardia using an accessory pathway, or AF associated with an accessory pathway for whom chronic drug therapy is planned
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Therapeutic Intervention
Class I recommendations for: Patients who are candidates for or who have implantable electrical devices
Patients with tachyarrhythmias before and during implantation and final (predischarge) programming of
an electrical device to confirm its ability to perform as anticipated
Patients with an implanted electrical antitachyarrhythmia device in whom changes in status or therapy may have influenced the continued safety and efficacy of the device
Patients who have a pacemaker to treat a bradyarrhythmia and receive an ICD to test for device interactions
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Therapeutic Intervention
Class I recommendations for: Indications for catheter ablation procedures
Patients with symptomatic atrial tachyarrhythmias who have inadequately controlled ventricular rates unless primary ablation of the atrial tachyarrhythmia is possible
Patients with symptomatic atrial tachyarrhythmias such as those above but in whom drugs are not tolerated, or the patient does not wish to take them, even though the ventricular rate can be controlled
Patients with symptomatic nonparoxysmal junctional tachycardia that is drug resistant, or the patient is drug intolerant or does not wish to take it
Patients resuscitated from sudden cardiac death caused by atrial flutter or AF with a rapid ventricular response in the absence of an accessory pathway
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Therapeutic Intervention
Class I recommendations for: Radiofrequency catheter ablation for AVNRT
Patients with symptomatic sustained AVNRT that is drug resistant, or the patient is drug intolerant or does not desire long-term drug therapy
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Therapeutic Intervention
Class I recommendations for: Ablation of atrial tachycardia, flutter, and fibrillation: atrium/atrial site
Patients with atrial tachycardia that is drug resistant, or the patient is drug intolerant or does not desire long-term drug therapy
Patients with atrial flutter that is drug resistant, or the patient is drug intolerant or does not desire long- term drug therapy
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Therapeutic Intervention
Class I recommendations for: Ablation of atrial tachycardia, flutter, and fibrillation: accessory pathways
Patients with symptomatic AV reentrant tachycardia that is drug resistant, or the patient is drug intolerant or does not desire long- term drug therapy
Patients with AF (or other atrial tachyarrhythmia) and a rapid ventricular response through the accessory pathway when the tachycardia is drug resistant, or the patient is drug intolerant or does not desire long-term drug therapy
The level 3 guidelines recommend a minimum of 2 year of specialized training in EPSs, during which the physician should be the primary operator and analyze ____ initial diagnostic studies, at least ___ of which should involve patients with supraventricular arrhythmias.
Initial diagnostic studies: 100 to 150
SVTs: 50
ACC/AHA 1995 Guidelines on Clinical Intracardiac Electrophysiologic Studies for Therapeutic Intervention
Class I recommendations for: Ablation of VT
Patients with symptomatic sustained monomorphic VT when the tachycardia is drug resistant, or the patient is drug intolerant or does not desire long-term drug therapy
Patients with bundle branch reentrant VT
Patients with sustained monomorphic VT and an ICD who are receiving multiple shocks not manageable
by reprogramming or concomitant drug therapy
Because antiarrhythmic devices constitute a major part of current electrophysiology practice, the guidelines suggest that a trainee should be the primary operator during at least ____ electrophysiologic evaluations of implantable antiarrhythmic devices.
25 EP evalutation of Implantable antiarrythmic device
For maintenance of competence, a minimum of ___ diagnostic EPSs per year is recommended
Diagnostic EPSs: 100/year
