RELIAS ASSESSMENTS ASSISTANCE MATERIAL DYSRHYTHMIAS #4
EKG interpretation - correct answer One of the most useful and commonly used
diagnostic tools is electrocardiography (EKG) which measures the heart's electrical
activity as waveforms. An EKG uses electrodes attached to the skin to detect electric
current moving through the heart. These signals are transmitted to produce a record of
cardiac activity. Arrhythmia or dysrhythmia are disturbances in the normal cardiac
rhythm of the heart which occurs as a result of alterations within the conduction of
electrical impulses. These impulses stimulate and coordinate atrial and ventricular
myocardial contractions that provide cardiac output.
Sinus Tachycardia - correct answer Sinus tachycardia is a heart rate greater than 100
beats per minute that originated from the sinus node.
Rate: 100 to 180 beats per minute
P Waves precede each QRS complex
PR interval is normal
QRS complex is normal
Conduction is normal
Rhythm is regular
Causes of sinus tachycardia may include exercise, anxiety, fever, drugs, anemia, heart
failure, hypovolemia and shock. Sinus tachycardia is often asymptomatic. Management
however is directed at the treatment of the primary cause. Carotid sinus pressure
(carotid massage) or a beta blocker may be used to reduce heart rate.
Sinus Bradycardia - correct answer Sinus bradycardia is a heart rate less than 60 beats
per minute and originates from the sinus node (as the term "sinus" refers to sinoatrial
node). It has the following characteristics
Rate is less than 60 beats per minute
P Waves precede each QRS complex
PR interval is normal
QRS complex is normal
Conduction is normal
Rhythm is regular
Causes may include drugs, vagal stimulation, hypoendocrine states, hypothermia, or
sinus node involvement in MI. This arrhythmia may be normal in athletes as they have
quality stroke volume. It is often asymptomatic but manifestations may include:
syncope, fatigue, dizziness. Management includes treating the underlying cause and
administering anticholinergic drugs like atropine sulfate as prescribed.
Premature Atrial Contraction - correct answer Premature Atrial Contraction are ectopic
beats that originates from the atria and they are not rhythms. Cells in the heart starts to
fire or go off before the normal heartbeat is supposed to occur. These are called heart
palpitations and has the following characteristics:
Premature and abnormal-looking P waves that differ in configuration from normal P
waves
QRS complex after P waves except in very early or blocked pacs
, P waves often buried in the preceding T wave or identified in the preceding T wave.
Causes includes coronary or valvular heart diseases, atrial ischemia, coronary artery
atherosclerosis, heart failure, COPD, electrolyte imbalance and hypoxia. Usually there
is no treatment needed but may include procainamide and quinidine administration
(antidysrhythmic drugs) and carotid sinus massage.
Atrial Flutter - correct answer Atrial flutter is an abnormal rhythm that occurs in the atria
of the heart. Atrial flutter has an atrial rhythm that is regular but has an atrial rate of 250
to 400 beats/minute. It has sawtooth appearance. QRS complexes are uniform in shape
but often irregular in rate.
Normal atrial rhythm
Abnormal atrial rate: 250 to 400 beats/minute
Sawtooth P wave configuration
QRS complexes uniform in shape but irregular in rate
Causes includes heart failure, tricuspid valve or mitral valve diseases, pulmonary
embolism, cor pulmonale, inferior wall MI, carditis and digoxin toxicity.
Management if the patient is unstable with ventricular rate of greater than 150 bpm,
prepare for immediate cardioversion. If patient is stable, drug therapy may include
calcium channel blocker, beta-adrenergic blockers, or antiarhythmics. Anticoagulation
may be necessary as there would be pooling of blood in the atria.
Atrial Fibrillation - correct answer Atrial fibrillation is disorganized and uncoordinated
twitching of atrial musculature caused by overly rapid production of atrial impulses. This
arrhythmia has the following characteristics:
Atrial Rate: 350 to 600 bpm
Ventricular Rate: 120 to 200 bpm
P wave is not discernible with an irregular baseline
PR interval is not measurable
QRS complex is normal
Rhythm is irregular and usually rapid unless controlled.
Causes includes atherosclerosis, heart failure, congenital heart disease, chronic
obstructive pulmonary disease, hypothyroidism and thyrotoxicosis. Atrial fibrillation may
be asymptomatic but clinical manifestation may include palpitations, dyspnea, and
pulmonary edema. Nursing goal is towards administration of prescribed treatment to
decrease ventricular response, decrease atrial irritability and eliminate the cause.
Premature Junctional Contraction - correct answer Premature Junctional Contraction
(PJC) occurs when some regions of the heart becomes excitable than normal. It has the
following characteristics.
PR interval less than 0.12 seconds if P wave precedes QRS complex
QRS complex configuration and duration is normal
P wave is inverted
Atrial and ventricular rhythms irregular
Causes of PJC may include myocardial infarction or ischemia, digoxin toxicity,
excessive caffeine or amphetamine use. Management includes correction of underlying
cause, discontinuation of digoxin if appropriate.
EKG interpretation - correct answer One of the most useful and commonly used
diagnostic tools is electrocardiography (EKG) which measures the heart's electrical
activity as waveforms. An EKG uses electrodes attached to the skin to detect electric
current moving through the heart. These signals are transmitted to produce a record of
cardiac activity. Arrhythmia or dysrhythmia are disturbances in the normal cardiac
rhythm of the heart which occurs as a result of alterations within the conduction of
electrical impulses. These impulses stimulate and coordinate atrial and ventricular
myocardial contractions that provide cardiac output.
Sinus Tachycardia - correct answer Sinus tachycardia is a heart rate greater than 100
beats per minute that originated from the sinus node.
Rate: 100 to 180 beats per minute
P Waves precede each QRS complex
PR interval is normal
QRS complex is normal
Conduction is normal
Rhythm is regular
Causes of sinus tachycardia may include exercise, anxiety, fever, drugs, anemia, heart
failure, hypovolemia and shock. Sinus tachycardia is often asymptomatic. Management
however is directed at the treatment of the primary cause. Carotid sinus pressure
(carotid massage) or a beta blocker may be used to reduce heart rate.
Sinus Bradycardia - correct answer Sinus bradycardia is a heart rate less than 60 beats
per minute and originates from the sinus node (as the term "sinus" refers to sinoatrial
node). It has the following characteristics
Rate is less than 60 beats per minute
P Waves precede each QRS complex
PR interval is normal
QRS complex is normal
Conduction is normal
Rhythm is regular
Causes may include drugs, vagal stimulation, hypoendocrine states, hypothermia, or
sinus node involvement in MI. This arrhythmia may be normal in athletes as they have
quality stroke volume. It is often asymptomatic but manifestations may include:
syncope, fatigue, dizziness. Management includes treating the underlying cause and
administering anticholinergic drugs like atropine sulfate as prescribed.
Premature Atrial Contraction - correct answer Premature Atrial Contraction are ectopic
beats that originates from the atria and they are not rhythms. Cells in the heart starts to
fire or go off before the normal heartbeat is supposed to occur. These are called heart
palpitations and has the following characteristics:
Premature and abnormal-looking P waves that differ in configuration from normal P
waves
QRS complex after P waves except in very early or blocked pacs
, P waves often buried in the preceding T wave or identified in the preceding T wave.
Causes includes coronary or valvular heart diseases, atrial ischemia, coronary artery
atherosclerosis, heart failure, COPD, electrolyte imbalance and hypoxia. Usually there
is no treatment needed but may include procainamide and quinidine administration
(antidysrhythmic drugs) and carotid sinus massage.
Atrial Flutter - correct answer Atrial flutter is an abnormal rhythm that occurs in the atria
of the heart. Atrial flutter has an atrial rhythm that is regular but has an atrial rate of 250
to 400 beats/minute. It has sawtooth appearance. QRS complexes are uniform in shape
but often irregular in rate.
Normal atrial rhythm
Abnormal atrial rate: 250 to 400 beats/minute
Sawtooth P wave configuration
QRS complexes uniform in shape but irregular in rate
Causes includes heart failure, tricuspid valve or mitral valve diseases, pulmonary
embolism, cor pulmonale, inferior wall MI, carditis and digoxin toxicity.
Management if the patient is unstable with ventricular rate of greater than 150 bpm,
prepare for immediate cardioversion. If patient is stable, drug therapy may include
calcium channel blocker, beta-adrenergic blockers, or antiarhythmics. Anticoagulation
may be necessary as there would be pooling of blood in the atria.
Atrial Fibrillation - correct answer Atrial fibrillation is disorganized and uncoordinated
twitching of atrial musculature caused by overly rapid production of atrial impulses. This
arrhythmia has the following characteristics:
Atrial Rate: 350 to 600 bpm
Ventricular Rate: 120 to 200 bpm
P wave is not discernible with an irregular baseline
PR interval is not measurable
QRS complex is normal
Rhythm is irregular and usually rapid unless controlled.
Causes includes atherosclerosis, heart failure, congenital heart disease, chronic
obstructive pulmonary disease, hypothyroidism and thyrotoxicosis. Atrial fibrillation may
be asymptomatic but clinical manifestation may include palpitations, dyspnea, and
pulmonary edema. Nursing goal is towards administration of prescribed treatment to
decrease ventricular response, decrease atrial irritability and eliminate the cause.
Premature Junctional Contraction - correct answer Premature Junctional Contraction
(PJC) occurs when some regions of the heart becomes excitable than normal. It has the
following characteristics.
PR interval less than 0.12 seconds if P wave precedes QRS complex
QRS complex configuration and duration is normal
P wave is inverted
Atrial and ventricular rhythms irregular
Causes of PJC may include myocardial infarction or ischemia, digoxin toxicity,
excessive caffeine or amphetamine use. Management includes correction of underlying
cause, discontinuation of digoxin if appropriate.
