B P7 C61 Approach to the Patient with Cardiac Arrhythmias Flashcards
(138 cards)
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)