Most people with supraventricular tachycardia don't need activity restrictions or treatment. For others, lifestyle changes, medication and heart procedures may be needed to control or eliminate the rapid heartbeats and related symptoms.
Types
Supraventricular tachycardia (SVT) falls into three main groups:
Atrioventricular nodal reentrant tachycardia (AVNRT). This is the most common type of supraventricular tachycardia.
Atrioventricular reciprocating tachycardia (AVRT). AVRT is the second most common type of supraventricular tachycardia. It's most commonly diagnosed in younger people.
Atrial tachycardia. This type of SVT is more commonly diagnosed in people who have heart disease. Atrial tachycardia doesn't involve the AV node.
Other types of supraventricular tachycardia include:
Sinus tachycardia
Sinus nodal reentrant tachycardia (SNRT)
Inappropriate sinus tachycardia (IST)
Multifocal atrial tachycardia (MAT)
Junctional ectopic tachycardia (JET)
Nonparoxysmal junctional tachycardia (NPJT)
Symptoms
The main symptom of supraventricular tachycardia (SVT) is a very fast heartbeat (100 beats a minute or more) that may last for a few minutes to a few days. The fast heartbeat may come and go suddenly, with stretches of typical heart rates in between.
Some people with SVT have no signs or symptoms.
Signs and symptoms of supraventricular tachycardia may include:
Very fast (rapid) heartbeat
A fluttering or pounding in the chest (palpitations)
A pounding sensation in the neck
Weakness or feeling very tired (fatigue)
Chest pain
Shortness of breath
Lightheadedness or dizziness
Sweating
Fainting (syncope) or near fainting
In infants and very young children, signs and symptoms of SVT may be difficult to identify. They include sweating, poor feeding, pale skin and a rapid pulse. If your infant or young child has any of these symptoms, ask your child's care provider about SVT screening.
When to see a doctor
Supraventricular tachycardia (SVT) is generally not life-threatening unless you have heart damage or other heart conditions. However, in extreme cases, an episode of SVT may cause unconsciousness or cardiac arrest.
Call your health care provider if you have an episode of a very fast heartbeat for the first time or if an irregular heartbeat lasts longer than a few seconds.
Some signs and symptoms of SVT may be related to a serious health condition. Call 911 or your local emergency number if you have an episode of SVT that lasts for more than a few minutes or if you have an episode with any of the following symptoms:
Chest pain
Shortness of breath
Weakness
Dizziness
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Causes
For some people, a supraventricular tachycardia (SVT
2. Patient with Supraventricular Tachycardia
Elisa Vasquez, 53 years old, is admitted to the
car diac unit with complaints of palpitations,
lightheadedness, and shortness of breath. Her
history reveals rheumatic fever at age 12 with
subsequent rheumatic heart disease and mitral
stenosis. An intravenous line is in place and she
is receiving oxygen. Marcia Lewin, RN, is
assigned to Ms. Vasquez.
SCENARIO
SCENARIO
3. Demographic data
Name:Mrs
Age:
Sex:Female
Diagnosis: Supraventricular Tachycardia
Elisa Vasquez
53 years
Complaints on admission:complaints of palpitations,
lightheadedness, and shortness of breath
𝙃𝙞𝙨𝙩𝙤𝙧𝙮 𝙊𝙁 𝙄𝙇𝙇𝙉𝙀𝙎𝙎
Ms. Vasquez is still complaining of palpitations
and tells Ms. Lewin, “I feel so nervous and weak
and dizzy.
Presenting complaints
4. . Vital signs: T 98.8° F (37.1°C), R 26, BP 95/60. Peripheral
pulses weak but equal, mucous membranes pale pink, skin
cool and dry. Fine crackles noted in both lung bases. A loud
S3 gallop and a diastolic murmur are noted. Ms. Vasquez is
still complaining of palpitations and tells Ms. Lewin, “I feel
so nervous and weak and dizzy.” Ms. Vasquez’s cardiologist
orders 2.5 mg of verapamil to be given slowly via
intravenous push and tells Ms. Lewin to prepare to assist
with synchronized cardioversion if drug therapy does not
control the ventricular rate."
Present medical history
complaints of palpitations, lightheadedness, and
shortness of breath at time of admission. An
intravenous line is in place and she is receiving
oxygen.
5. 𝙋𝙖𝙨𝙩 𝙢𝙚𝙙𝙞𝙘𝙖𝙡 𝙝𝙞𝙨𝙩𝙤𝙧𝙮
Her history reveals rheumatic fever at age 12 with
subsequent rheumatic heart disease and mitral stenosis.
𝙉𝙤 𝙤𝙩𝙝𝙚𝙧 𝙙𝙖𝙩𝙖 𝙖𝙗𝙤𝙪𝙩 𝙥𝙖𝙩𝙞𝙚𝙣𝙩 𝙤𝙧 𝙛𝙖𝙢𝙞𝙡𝙮 𝙞𝙨 𝙖𝙫𝙖𝙞𝙡𝙖𝙗𝙡𝙚
𝙞𝙣 𝙨𝙘𝙚𝙣𝙖𝙧𝙞𝙤
𝙋𝙝𝙮𝙨𝙞𝙘𝙖𝙡 𝙚𝙭𝙖𝙢𝙞𝙣𝙖𝙩𝙞𝙤𝙣
. Vital signs: T 98.8° F (37.1°C), R 26, BP 95/60.
Peripheral pulses weak but equal, mucous membranes
pale pink, skin cool and dry. Fine crackles noted in both
lung bases. A loud S3 gallop and a diastolic murmur
An intravenous line is in place and she is receiving
oxygen.
palpitations 𝙥𝙧𝙚𝙨𝙚𝙣𝙩
6. Mid-diastolic murmurs start after S2 and end before S1.
They are due to turbulent flow across the atrioventricular
(mitral & tricuspid) valves during the rapid filling phase
from mitral or tricuspid stenosis. Late diastolic
(presystolic) murmurs start after S2 and extend up to S1
and have a crescendo configuration.
third heart sound (S3), also known as the “ventricular
gallop,” occurs just after S2 when the mitral valve
opens, allowing passive filling of the left ventricle. ... A
S3 can be a normal finding in children, pregnant
females and well-trained athletes; however, a S4 heart
sound is almost always abnormal.
13. 𝙍𝙚𝙫𝙞𝙚𝙬 𝙤𝙛 𝙖𝙣𝙖𝙩𝙤𝙢𝙮 𝙖𝙣𝙙 𝙥𝙝𝙮𝙨𝙞𝙤𝙡𝙤𝙜𝙮
The heart itself is made up of 4 chambers, 2 atria and
2 ventricles. De-oxygenated blood returns to the right
side of the heart via the venous circulation. It is
pumped into the right ventricle and then to the lungs
where carbon dioxide is released and oxygen is
absorbed.
• main functions of the heart are:
Pumping oxygenated blood to the other body parts.
Pumping hormones and other vital substances to
different parts of the body.
Receiving deoxygenated blood and carrying
metabolic waste products from the body and
pumping it to the lungs for oxygenation.
Maintaining blood pressure
14. The sequence of electrical events during one full
contraction of the heart muscle:
An excitation signal (an action potential) is created by
the sinoatrial (SA) node.
The wave of excitation spreads across the atria,
causing them to contract.
Upon reaching the atrioventricular (AV) node, the
signal is delayed.
It is then conducted into the bundle of His, down the
interventricular septum.
The bundle of His and the Purkinje fibres spread the
wave impulses along the ventricles, causing them to
contract.
𝘾𝙤𝙣𝙙𝙪𝙘𝙩𝙞𝙣𝙜 𝙨𝙮𝙨𝙩𝙚𝙢 𝙤𝙛 𝙝𝙚𝙖𝙧𝙩
15.
16.
17. QRS duration represents the time for ventricular
depolarization. The duration is normally 0.06 to 0.10
seconds.
18.
19.
20. normal PR interval is 0.12 to 0.20 seconds, or 120 to
200 milliseconds.
normal
duration
(interval) of
the QRS
complex is
between
0.08 and
0.10
seconds —
that is, 80
and 100
milliseconds
21. SUPRAVENTRICULAR’ TACHYCARDIAS
SUPRAVENTRICULAR’ TACHYCARDIAS AV NODAL
RE-ENTRY TACHYCARDIA (AVNRT) This is due to re-entry in
the right atrium and AV node, and tends to occur in hearts
that are otherwise normal. It produces episodes of regular
tachy-cardia with a rate of 140–220/min that last from a few
seconds to many hours.
patient is usually aware of a fast heart beat and
may feel faint or breathless.
Polyuria may occur, and also angina if there is
underlying coronary disease
Attacks may be terminated by carotid sinus
pressure or Valsalva manoeuvre, but if not, i.v.
adenosine or verapamil will restore sinus rhythm in
most cases
𝘿𝙚𝙛𝙞𝙣𝙞𝙩𝙞𝙤𝙣
22. ECG (Fig. 8.3) usually shows a regular tachycardia
with normal QRS complexes but occasionally
there may be rate-dependent bundle branch block
When there is severe haemodynamic com-promise,
the tachycardia should be terminated by DC
cardioversion
• If attacks are frequent or disabling, prophylactic
oral therapy (e.g. β-blocker, verapamil) may be
indicated but catheter ablation (p. 228) offers a
very high chance of complete cure and is usually
preferable to long-term drug treatment.
23. ATRIOVENTRICULAR RE-ENTRANT
TACHYCARDIA (AVRT) AND WOLFF–
PARKINSON–WHITE SYNDROME
An abnormal band of rapidly conducting tissue
(‘accessory pathway’) con-nects the atria and
ventricles. In around half of cases, premature
activation of ventricular tissue via the pathway
produces a short PR interval and a ‘slur-ring’ of
the QRS complex, called a delta wave
As the AV node and bypass tract have different
conduction speeds and refractory periods, a re-
entry circuit can develop, causing tachycardia;
when associated with symp-toms, the condition is
known as Wolff–Parkinson–White syndrome.
𝙋𝙖𝙩𝙝𝙤𝙥𝙝𝙮𝙨𝙞𝙤𝙡𝙤𝙜𝙮 𝙤𝙛 𝙨𝙫𝙩
25. The incidence of SVT is approximately 35
cases per 100,000 patients with a
prevalence of 2.25 cases per 1,000 in the
general population. Atrial fibrillation and
atrial flutter are the most common
subtypes of SVT, affecting approximately 2
million patients in the United States.
𝙄𝙣𝙘𝙞𝙙𝙚𝙣𝙘𝙚
26. 𝘽𝙤𝙤𝙠 𝙥𝙞𝙘𝙩𝙪𝙧𝙚
𝙋𝙖𝙩𝙞𝙚𝙣𝙩 𝙥𝙞𝙘𝙩𝙪𝙧𝙚
𝙎𝙩𝙧𝙪𝙘𝙩𝙪𝙧𝙖𝙡 𝙖𝙣𝙤𝙢𝙖𝙡𝙞𝙩𝙮
(𝙈𝙄𝙏𝙍𝘼𝙇 𝙎𝙏𝙀𝙉𝙊𝙎𝙄𝙎
• 𝙂𝙚𝙣𝙙𝙚𝙧
• 𝙁𝙚𝙢𝙖𝙡𝙚 𝙥𝙖𝙩𝙞𝙚𝙣𝙩
𝙢𝙤𝙧𝙚 𝙥𝙧𝙤𝙣𝙚
Estrogen and progesterone
levels rise and fall in
women with a normal
menstrual cycle during the
days of the month. The
rise of progesterone and
the fall of estrogen
correspond with: More
frequent episodes of
supraventricular
tachycardia (SVT)
• 𝘼𝙜𝙚
Coronary artery
disease, other heart
problems and
previous heart surgery.
Congenital heart
diseas
Thyroid 𝙥𝙧𝙤𝙗𝙡𝙚𝙢𝙨
Drugs and
𝙨𝙪𝙥𝙥𝙡𝙚𝙢𝙚𝙣𝙩𝙨
Anxiety or emotional
stress.
Physical fatigue.
Diabetes.
• Anxiety
𝙍𝙞𝙨𝙠 𝙛𝙖𝙘𝙩𝙤𝙧𝙨
27. SYMPTOMS
Book picture
•
•
•
rapid tachycardia of
abrupt onset and
termination
Dizziness can occur
initially because of
hypotension
continuous pulsing
cannon A waves in
the jugular venous
waveform (described
as the “frog” sign)
?𝙋𝙖𝙩𝙞𝙚𝙣𝙩 𝙥𝙞𝙘𝙩𝙪𝙧𝙚
• ECG shows
supraventricular
tachycardia (SVT) with
a rate of 154. Vital
signs: T 98.8° F (37.1°C)
, R 26, BP 95/60
• nervous and weak and
dizzy.
28. • palpitations and
heart racing,
frequently
associated with
complaints of
dyspnea, weakness,
chest pain, dizziness,
or even frank
syncope.
• patients with
underlying
structural heart
disease,
symptoms can be
more severe
𝘽𝙤𝙤𝙠 𝙥𝙞𝙘𝙩𝙪𝙧𝙚
• Peripheral pulses weak but
equal, mucous
membranes pale pink, skin
cool and dry. Fine crackles
noted in both lung bases.
A loud S3 gallop and a
diastolic murmur.
• complaining of palpitations
𝙋𝙖𝙩𝙞𝙚𝙣𝙩 𝙥𝙞𝙘𝙩𝙪𝙧𝙚
• lightheadedness, and
shortness of breath
• history reveals rheumatic
fever at age 12 with
subsequent rheumatic heart
disease and mitral stenosis.
29. 𝘿𝙞𝙖𝙜𝙣𝙤𝙨𝙩𝙞𝙘 𝙀𝙫𝙖𝙡𝙪𝙖𝙩𝙞𝙤𝙣
𝘽𝙊𝙊𝙆 𝙋𝙄𝘾𝙏𝙐𝙍𝙀
𝙋𝙖𝙩𝙞𝙚𝙣𝙩 𝙥𝙞𝙘𝙩𝙪𝙧𝙚
• History, physical
examination, and an
electrocardiogram (ECG)
con-stitute an appropriate
initial evaluation of
patients presenting with
symptoms suggestive of
paroxysmal SVT.
History, physical
examination, and an
electrocardiogram (ECG)
• Ambulatory 24- or 48-
hour Holter recording
• A cardiac event
monitor,Implantable
loop recorders can be
helpful in selected
cases with rare
episodes associated
with severe symptoms
of hemodynamic
instability (e.g.,
syncope).
• An echocardiographic
examination
33. Stable client with sustained VT (with pulse and no
signs or symptoms of decreasedcardiac output)
• a. Administer oxygen as prescribed.
b. Administer antidysrhythmics as prescribed.
3. Unstable client with VT (with pulse and signs and
symptoms of decreasedcardiac output) a. Administer
oxygen and antidysrhythmic ther-apy as prescribed.
b. Prepare for synchronized cardioversion if the client
is unstable.
c. Attempt cough cardiopulmonary resuscita-tion
(CPR) by asking the client to cough hard every 1 to 3
seconds.
4. Pulseless client with ventricular tachycardia:
defibrillation and CPR
𝙉𝙐𝙍𝙎𝙄𝙉𝙂 𝙈𝘼𝙉𝘼𝙂𝙀𝙈𝙀𝙉𝙏
34. ASSESSMENT
Ms. Lewin’s assessment reveals that Ms. Vasquez is
moderately anxious. Her ECG shows supraventricular
tachycardia (SVT) with a rate of 154. Vital signs: T 98.8° F
(37.1°C), R 26, BP 95/60. Peripheral pulses weak but
equal, mucous membranes pale pink, skin cool and dry.
Fine crackles noted in both lung bases. A loud S3 gallop
and a diastolic murmur are noted. Ms. Vasquez is still
complaining of palpitations and tells Ms. Lewin, “I feel so
nervous and weak and dizzy.” Ms. Vasquez’s cardiologist
orders 2.5 mg of verapamil to be given slowly via
intravenous push and tells Ms. Lewin to prepare to assist
with synchronized cardioversion if drug therapy does not
control the ventricular rate."
Nursing care plan
35. DIAGNOSIS
Ms. Lewin formulates the following nursing diagnoses for Ms.
Vasquez.
• Decreased cardiac output related to inadequate ventricular
fill-ing associated with rapid tachycardia
• Ineffective tissue perfusion:cerebral/cardiopulmonary/
peripheral related to decreased cardiac 𝙤𝙪𝙩𝙥𝙪𝙩
• Anxiety related to unknown outcome of altered health 𝙨𝙩𝙖𝙩𝙚
EXPECTED OUTCOMES The expected outcomes for the
plan of care specify that Ms.
Vasquez will:
• Maintain adequate cardiac output and tissue perfusion.
• Demonstrate a ventricular rate within normal limits and
stable vital signs.
• Verbalize reduced anxiety.
• Verbalize an understanding of the rationale for the
treatment measures to control the heart rate
𝙉𝙪𝙧𝙨𝙞𝙣𝙜 𝙘𝙖𝙧𝙚 𝙥𝙡𝙖𝙣
36. •
•
Nursing Interventions
Monitoring and Managing the Dysrhythmia
• Minimizing Anxiety When the patient experiences
episodes of dysrhyth-mia, the nurse stays with the
patient and provides assurance of safety and
security while maintaining a calm and reassuring
attitude.
•
•
Promoting Home and Community-Based Care
TEACHING PATIENTS SELF-CARE.
When teaching patients about dysrhythmias, the
nurse fi rst assesses the patient’s understanding,
clarif i es misinformation, and then shares
needed information in terms that are
understandable and in a manner that is not
frighten-ing or threatening.
37. Valsalva maneuver
a. The physician instructs the client to bear down or
induces a gag reflex in the client to stimulate a
vagal response b. Monitor the heart rate, rhythm,
andBP.
c. Observe the cardiac monitor for a change in
rhythm.
d. Record an electrocardiographic rhythm strip
before, during, and after the procedure.
e. Provide an emesis basin if the gag reflex is
stimulated, and initiate precautions to prevent
aspiration.
f. Have a defibrillator and resuscitative equip-ment
available.
38. MANAGEMENT OF DYSRHYTHMIAS
. . Vagal maneuver:induce vagal stimulation of the
cardiac conduction system and are used to terminate
supraventricular tachydysrhythmias.
a. The physician instructs the client to turn the head
away from the side to be massaged
. Carotid sinus massage
b. The physician massages over one carotid artery for a few
seconds to determine whether a change in cardiac rhythm
occurs.
c. The client should be on a cardiac monitor;
an electrocardiographic rhythm strip before, during, and after
the procedure should be documented on the chart.
d. Have a defibrillator and resuscitative equip-ment available.
e. Monitor vital signs, cardiac rhythm, and level of
consciousness following the procedure.
45. B. . Cardioversion is synchronized countershock to convert
an undesirable rhythm to a stable rhythm.
b. Cardioversion can be an elective procedure performed by
the physician for stable tachy-dysrhythmias resistant to
medical therapies or an emergent procedure for
hemodynami-cally unstable ventricular or supraventricular
tachydysrhythmias.
c. A lower amount of energy is used than with defibrillation.
d. The defibrillator is synchronized to the cli-ent’s R wave to
avoid discharging the shock during the vulnerable period (T
wave).
e. If the defibrillator were not synchronized, it could
discharge on the T wave and cause VF.
46. 2. Preprocedure interventions
a. Obtain an informed consent if an elective procedure.
b. Administer sedation as prescribed.
c. Ifanelectiveprocedure,holddigoxin(Lanoxin) 48 hours
preprocedure as prescribed to prevent postcardioversion
ventricular irritability.
d. If an elective procedure for atrial fibrillation or atrial
flutter, the client should receive anticoagulant therapy for
4 to 6 weeks preprocedure.
3. During the procedure
a. Ensure that the skin is clean and dry in the area where
the electrode paddles will be placed.
b. Stop the oxygen during the procedure to avoid the
hazard of fire.
c. Be sure that no one is touching the bed or the client
when delivering the countershock.
47. 4. Postprocedure interventions
a. Priority assessment includes ability of the cli-ent
to maintain the airway and breathing.
b. Resume oxygen administration as prescribed.
c. Assess vital signs.
d. Assess level of consciousness.
e. Monitor cardiac rhythm.
f. Monitor for indications of successful response,
such as conversion to sinus rhythm, strong
peripheral pulses, an ade-quateBP, and adequate
urine output.
g. Assess the skin on the chest for evidence of
burns from the edges of the paddles.
48. Defibrillation
1. Defibrillation is an asynchronous countershock
used to terminate pulseless ventricular tachycar-
dia (VT) or VF.
2. Three rapid consecutive shocks are delivered,
with the first at an energy of 200 J.
3. Ifunsuccessful,theshockisrepeatedat200to300J.
4. The third and subsequent shocks will be 360 J.
Before defibrillating a client be sure that the
oxygen is shut off to avoid the hazard of fire and
be sure that no one is touching the bed or the
client.
D. Use of paddle electrodes
E. Automatic external defibrillator
F. Implantable cardioverter-defibrillator (ICD)
53. Evaluation Expected Patient Outcomes Expected
patient outcomes may include:
1. Maintains cardiac output
a. Demonstrates heart rate, blood pressure, respi-
ratory rate, and level of consciousness within normal
ranges
b. Demonstrates no or decreased episodes of
𝙙𝙮𝙨𝙧𝙝𝙮𝙩𝙝𝙢𝙞𝙖
2. Experiences reduced anxiety
3. Expresses understanding of the dysrhythmia and its
treatment
54. 1. What is the scientific basis for using carotid
massage to treat supraventricular tachycardias?
Was this an appropriate ma-neuver in the case of
Ms.Vasquez?
2. What other treatment options might the
physician have used to treat Ms.Vasquez’s
supraventricular tachycardia if she had been
asymptomatic with stable vital signs?
3. Develop a teaching plan for Ms.Vasquez
related to her pre-scription for furosemide.
Evaluation questions?
?
55. ℍ𝕖𝕒𝕝𝕥𝕙 𝕖𝕕𝕦𝕔𝕒𝕥𝕚𝕠𝕟 𝕗𝕠𝕣 𝕡𝕒𝕥𝕚𝕖𝕟𝕥 𝕙𝕒𝕧𝕚𝕟𝕘 𝕤𝕧𝕥
• Have less alcohol and caffeine
Don't smoke
Lower your stress
Eat foods that are healthy for your heart
Don't take recreational drugs, especially stimulants that can over-excite the heart
muscle. Some herbs and supplements can have this same effect. Always check with
your healthcare team before you take any non-prescribed medicines.
Stay well hydrated and get enough sleep
• 𝘼𝙜𝙚
Coronary artery disease, other heart problems
and previous heart surgery.
Congenital heart diseas
Thyroid 𝙥𝙧𝙤𝙗𝙡𝙚𝙢𝙨
Drugs and 𝙨𝙪𝙥𝙥𝙡𝙚𝙢𝙚𝙣𝙩𝙨
Anxiety or emotional stress.
Physical fatigue.
𝕄𝕒𝕜𝕖 𝕡𝕒𝕥𝕚𝕖𝕟𝕥 𝕒𝕨𝕒𝕣𝕖
𝕒𝕓𝕠𝕦𝕥 𝕥𝕙𝕚𝕤 𝕣𝕚𝕤𝕜 𝕗𝕒𝕔𝕥𝕠𝕣𝕤 𝕗𝕠𝕣
𝕊𝕦𝕡𝕣𝕒𝕧𝕖𝕟𝕥𝕣𝕚𝕔𝕦𝕝𝕒𝕣
𝕥𝕒𝕔𝕙𝕪𝕔𝕒𝕣𝕕𝕚𝕒
57. 𝘿𝙄𝙎𝘾𝙃𝘼𝙍𝙂𝙀 𝙋𝙇𝘼𝙉𝙉𝙄𝙉𝙂
Perform vagal maneuvers as directed when you have
symptoms of SVT. Lie down flat and bear down like you
are having a bowel movement. Do this for 10 to 30
seconds.
Do not drink caffeine or alcohol. These can increase your
risk for SVT.
Keep a record of your symptoms. Write down what you
ate or what you were doing before an episode of SVT.
Also write down anything you did to make the SVT stop.
Bring your record to follow up visits with your healthcare
provider.
Eat heart-healthy foods. These include fruits, vegetables,
whole-grain breads, low-fat dairy products, beans, lean
meats, and fish. Replace butter and margarine with
heart-healthy oils such as olive oil and canola oil.
58. • Exercise regularly and maintain a healthy weight.
Ask about the best exercise plan for you. Ask your
healthcare provider what a healthy weight is for
you. Ask him or her to help you create a safe
weight loss plan if you are overweight.
59. • Do not smoke. Nicotine and other chemicals in
cigarettes and cigars can cause heart and lung
damage. Ask your healthcare provider for
information if you currently smoke and need help
to quit. E-cigarettes or smokeless tobacco still
contain nicotine. Talk to your healthcare provider
before you use these products.
Manage other health conditions. Take medicine
as directed and follow your treatment plan. Your
healthcare provider may need to change a
medicine you are taking if it is causing your SVT.
Do not stop taking any medicine unless directed
by your provider.
60. 𝙎𝙪𝙢𝙢𝙖𝙧𝙮???
Supraventricular tachycardias (SVTs) are a group
of tachyarrhythmias arising from abnormalities
in pacemaker activity and/or conduction
involving myocytes of the atria and/or AV node.
Types of SVT include atrioventricular nodal
reentrant tachycardia (AVNRT; approx. two-thirds
of cases), atrioventricular reciprocating (or
reentrant) tachycardia (AVRT), focal atrial
tachycardia (FAT), multifocal atrial tachycardia
(MAT), and junctional tachycardia. AVNRT and
AVRT are caused by abnormal conduction
circuits that form an unending loop of conduction
referred to as reentry.
61. 𝘾𝙤𝙣𝙘𝙡𝙪𝙨𝙞𝙤𝙣
supraventricular tachycardias produce serious
symp-toms and can dramatically impair quality of
life. Apart from the obvious haemodynamic and
thromboembolic risks already discussed, the
psychological impact of SVT should not be
underestimated. Patients feel insecure and
vulnerable when their hearts inexplicably accelerate
and they become aware of an abnormal cardiac
rhythm.
Whilst many will respond to reassurance, many
others do not. Many fear for their lives each time the
arrhythmia occurs.
Supraventricular tachycardias frequently threaten
the quality of life but only rarely threaten life
62. 𝘽𝙞𝙗𝙡𝙞𝙤𝙜𝙧𝙖𝙥𝙝𝙮
1. Holter NJ: New method for heart studies. Science,
1961; 134: 1214–1229.
2. Bleifer SB, Bleifer DJ, Hansmann DR, Sheppard JJ,
and Karpmann HL: Diagnosis of occult arrhythmias by
Holter electrocardiography. Prog Cardiovasc Dis 1974;
16: 569–599.
3. Lipski J, Cohen L, Espinoso J, Motro M, Dack S, and
Donoso E: Value of Holter monitoring in assessing
cardiac arrhythmias in symptomatic patients. Am J
Cardiol 1976; 37: 102–109.