Tachycardia

Last updated
Tachycardia
Other namesTachyarrhythmia
Tachycardia ECG paper.svg
ECG showing sinus tachycardia with a rate of about 100 beats per minute
Pronunciation
Specialty Cardiology
Differential diagnosis

Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. [1] In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults. [1] Heart rates above the resting rate may be normal (such as with exercise) or abnormal (such as with electrical problems within the heart).

Contents

Complications

Tachycardia can lead to fainting. [2]

When the rate of blood flow becomes too rapid, or fast blood flow passes on damaged endothelium, it increases the friction within vessels resulting in turbulence and other disturbances. [3] According to the Virchow's triad, this is one of the three conditions that can lead to thrombosis (i.e., blood clots within vessels). [4]

Causes

Some causes of tachycardia include: [5]

Drug related:

Diagnosis

The upper threshold of a normal human resting heart rate is based on age. Cutoff values for tachycardia in different age groups are fairly well standardized; typical cutoffs are listed below: [7] [8]

Heart rate is considered in the context of the prevailing clinical picture. When the heart beats excessively or rapidly, the heart pumps less efficiently and provides less blood flow to the rest of the body, including the heart itself. The increased heart rate also leads to increased work and oxygen demand by the heart, which can lead to rate related ischemia. [9]

Differential diagnosis

12 lead electrocardiogram showing a ventricular tachycardia (VT) Electrocardiogram of Ventricular Tachycardia.png
12 lead electrocardiogram showing a ventricular tachycardia (VT)

An electrocardiogram (ECG) is used to classify the type of tachycardia. They may be classified into narrow and wide complex based on the QRS complex. [10] Equal or less than 0.1s for narrow complex. [11] Presented in order of most to least common, they are: [10]

Tachycardias may be classified as either narrow complex tachycardias (supraventricular tachycardias) or wide complex tachycardias. Narrow and wide refer to the width of the QRS complex on the ECG. Narrow complex tachycardias tend to originate in the atria, while wide complex tachycardias tend to originate in the ventricles. Tachycardias can be further classified as either regular or irregular.[ citation needed ]

Sinus

The body has several feedback mechanisms to maintain adequate blood flow and blood pressure. If blood pressure decreases, the heart beats faster in an attempt to raise it. This is called reflex tachycardia. This can happen in response to a decrease in blood volume (through dehydration or bleeding), or an unexpected change in blood flow. The most common cause of the latter is orthostatic hypotension (also called postural hypotension). Fever, hyperventilation, diarrhea and severe infections can also cause tachycardia, primarily due to increase in metabolic demands.[ citation needed ]

Upon exertion, sinus tachycardia can also be seen in some inborn errors of metabolism that result in metabolic myopathies, such as McArdle's disease (GSD-V). [12] [13] Metabolic myopathies interfere with the muscle's ability to create energy. This energy shortage in muscle cells causes an inappropriate rapid heart rate in response to exercise. The heart tries to compensate for the energy shortage by increasing heart rate to maximize delivery of oxygen and other blood borne fuels to the muscle cells. [12]

"In McArdle's, our heart rate tends to increase in what is called an 'inappropriate' response. That is, after the start of exercise it increases much more quickly than would be expected in someone unaffected by McArdle's." [14] As skeletal muscle relies predominantly on glycogenolysis for the first few minutes as it transitions from rest to activity, as well as throughout high-intensity aerobic activity and all anaerobic activity, individuals with GSD-V experience during exercise: sinus tachycardia, tachypnea, muscle fatigue and pain, during the aforementioned activities and time frames. [12] [13] Those with GSD-V also experience "second wind", after approximately 6–10 minutes of light-moderate aerobic activity, such as walking without an incline, where the heart rate drops and symptoms of exercise intolerance improve. [12] [13] [14]

An increase in sympathetic nervous system stimulation causes the heart rate to increase, both by the direct action of sympathetic nerve fibers on the heart and by causing the endocrine system to release hormones such as epinephrine (adrenaline), which have a similar effect. Increased sympathetic stimulation is usually due to physical or psychological stress. This is the basis for the so-called fight-or-flight response, but such stimulation can also be induced by stimulants such as ephedrine, amphetamines or cocaine. Certain endocrine disorders such as pheochromocytoma can also cause epinephrine release and can result in tachycardia independent of nervous system stimulation. Hyperthyroidism can also cause tachycardia. [15] The upper limit of normal rate for sinus tachycardia is thought to be 220 bpm minus age.[ citation needed ]

Inappropriate sinus tachycardia

Inappropriate sinus tachycardia (IST) is a diagnosis of exclusion, [16] a rare but benign type of cardiac arrhythmia that may be caused by a structural abnormality in the sinus node. It can occur in seemingly healthy individuals with no history of cardiovascular disease. Other causes may include autonomic nervous system deficits, autoimmune response, or drug interactions. Although symptoms might be distressing, treatment is not generally needed. [17]

Ventricular

Ventricular tachycardia (VT or V-tach) is a potentially life-threatening cardiac arrhythmia that originates in the ventricles. It is usually a regular, wide complex tachycardia with a rate between 120 and 250 beats per minute. A medically significant subvariant of ventricular tachycardia is called torsades de pointes (literally meaning "twisting of the points", due to its appearance on an EKG), which tends to result from a long QT interval. [18]

Both of these rhythms normally last for only a few seconds to minutes (paroxysmal tachycardia), but if VT persists it is extremely dangerous, often leading to ventricular fibrillation. [19] [20]

Supraventricular

This is a type of tachycardia that originates from above the ventricles, such as the atria. It is sometimes known as paroxysmal atrial tachycardia (PAT). Several types of supraventricular tachycardia are known to exist. [21]

Atrial fibrillation

Atrial fibrillation is one of the most common cardiac arrhythmias. In general, it is an irregular, narrow complex rhythm. However, it may show wide QRS complexes on the ECG if a bundle branch block is present. At high rates, the QRS complex may also become wide due to the Ashman phenomenon. It may be difficult to determine the rhythm's regularity when the rate exceeds 150 beats per minute. Depending on the patient's health and other variables such as medications taken for rate control, atrial fibrillation may cause heart rates that span from 50 to 250 beats per minute (or even higher if an accessory pathway is present). However, new-onset atrial fibrillation tends to present with rates between 100 and 150 beats per minute. [22]

AV nodal reentrant tachycardia

AV nodal reentrant tachycardia (AVNRT) is the most common reentrant tachycardia. It is a regular narrow complex tachycardia that usually responds well to the Valsalva maneuver or the drug adenosine. However, unstable patients sometimes require synchronized cardioversion. Definitive care may include catheter ablation. [23]

AV reentrant tachycardia

AV reentrant tachycardia (AVRT) requires an accessory pathway for its maintenance. AVRT may involve orthodromic conduction (where the impulse travels down the AV node to the ventricles and back up to the atria through the accessory pathway) or antidromic conduction (which the impulse travels down the accessory pathway and back up to the atria through the AV node). Orthodromic conduction usually results in a narrow complex tachycardia, and antidromic conduction usually results in a wide complex tachycardia that often mimics ventricular tachycardia. Most antiarrhythmics are contraindicated in the emergency treatment of AVRT, because they may paradoxically increase conduction across the accessory pathway. [ citation needed ]

Junctional tachycardia

Junctional tachycardia is an automatic tachycardia originating in the AV junction. It tends to be a regular, narrow complex tachycardia and may be a sign of digitalis toxicity. [24]

Management

The management of tachycardia depends on its type (wide complex versus narrow complex), whether or not the person is stable or unstable, and whether the instability is due to the tachycardia. [10] Unstable means that either important organ functions are affected or cardiac arrest is about to occur. [10]

Unstable

In those that are unstable with a narrow complex tachycardia, intravenous adenosine may be attempted. [10] In all others immediate cardioversion is recommended. [10]

Terminology

The word tachycardia came to English from Neo-Latin as a neoclassical compound built from the combining forms tachy- + -cardia , which are from the Greek ταχύς tachys, "quick, rapid" and καρδία, kardia, "heart". As a matter both of usage choices in the medical literature and of idiom in natural language, the words tachycardia and tachyarrhythmia are usually used interchangeably, or loosely enough that precise differentiation is not explicit. Some careful writers have tried to maintain a logical differentiation between them, which is reflected in major medical dictionaries [25] [26] [27] and major general dictionaries. [28] [29] [30] The distinction is that tachycardia be reserved for the rapid heart rate itself, regardless of cause, physiologic or pathologic (that is, from healthy response to exercise or from cardiac arrhythmia), and that tachyarrhythmia be reserved for the pathologic form (that is, an arrhythmia of the rapid rate type). This is why five of the previously referenced dictionaries do not enter cross-references indicating synonymy between their entries for the two words (as they do elsewhere whenever synonymy is meant), and it is why one of them explicitly specifies that the two words not be confused. [27] But the prescription will probably never be successfully imposed on general usage, not only because much of the existing medical literature ignores it even when the words stand alone but also because the terms for specific types of arrhythmia (standard collocations of adjectives and noun) are deeply established idiomatically with the tachycardia version as the more commonly used version. Thus SVT is called supraventricular tachycardia more than twice as often as it is called supraventricular tachyarrhythmia; moreover, those two terms are always completely synonymous—in natural language there is no such term as "healthy/physiologic supraventricular tachycardia". The same themes are also true of AVRT and AVNRT. Thus this pair is an example of when a particular prescription (which may have been tenable 50 or 100 years earlier) can no longer be invariably enforced without violating idiom. But the power to differentiate in an idiomatic way is not lost, regardless, because when the specification of physiologic tachycardia is needed, that phrase aptly conveys it.[ citation needed ]

See also

Related Research Articles

<span class="mw-page-title-main">Bradycardia</span> Heart rate below the normal range

Bradycardia, also called bradyarrhythmia, is a resting heart rate under 60 beats per minute (BPM). While bradycardia can result from a variety of pathologic processes, it is commonly a physiologic response to cardiovascular conditioning, or due to asymptomatic type 1 atrioventricular block. Resting heart rates less than 50 BPM are often normal during sleep in young and healthy adults, and in athletes. In large population studies of adults without underlying heart disease, resting heart rates of 45-50 BPM appear to be the lower limits of normal, dependent on age and sex. Bradycardia is most likely to be discovered in the elderly, as both age and underlying cardiac disease progression contribute to its development.

<span class="mw-page-title-main">Electrocardiography</span> Examination of the hearts electrical activity

Electrocardiography is the process of producing an electrocardiogram, a recording of the heart's electrical activity through repeated cardiac cycles. It is an electrogram of the heart which is a graph of voltage versus time of the electrical activity of the heart using electrodes placed on the skin. These electrodes detect the small electrical changes that are a consequence of cardiac muscle depolarization followed by repolarization during each cardiac cycle (heartbeat). Changes in the normal ECG pattern occur in numerous cardiac abnormalities, including:

<span class="mw-page-title-main">Cardioversion</span> Conversion of a cardiac arrhythmia to a normal rhythm using an electrical shock or medications

Cardioversion is a medical procedure by which an abnormally fast heart rate (tachycardia) or other cardiac arrhythmia is converted to a normal rhythm using electricity or drugs. Synchronized electrical cardioversion uses a therapeutic dose of electric current to the heart at a specific moment in the cardiac cycle, restoring the activity of the electrical conduction system of the heart. Pharmacologic cardioversion, also called chemical cardioversion, uses antiarrhythmia medication instead of an electrical shock.

<span class="mw-page-title-main">Wolff–Parkinson–White syndrome</span> Medical condition

Wolff–Parkinson–White syndrome (WPWS) is a disorder due to a specific type of problem with the electrical system of the heart involving an accessory pathway able to conduct electrical current between the atria and the ventricles, thus bypassing the atrioventricular node. About 60% of people with the electrical problem developed symptoms, which may include an abnormally fast heartbeat, palpitations, shortness of breath, lightheadedness, or syncope. Rarely, cardiac arrest may occur. The most common type of irregular heartbeat that occurs is known as paroxysmal supraventricular tachycardia.

<span class="mw-page-title-main">Atrial flutter</span> Medical condition

Atrial flutter (AFL) is a common abnormal heart rhythm that starts in the atrial chambers of the heart. When it first occurs, it is usually associated with a fast heart rate and is classified as a type of supraventricular tachycardia. Atrial flutter is characterized by a sudden-onset (usually) regular abnormal heart rhythm on an electrocardiogram (ECG) in which the heart rate is fast. Symptoms may include a feeling of the heart beating too fast, too hard, or skipping beats, chest discomfort, difficulty breathing, a feeling as if one's stomach has dropped, a feeling of being light-headed, or loss of consciousness.

<span class="mw-page-title-main">Ventricular tachycardia</span> Medical condition of the heart

Ventricular tachycardia is a cardiovascular disorder in which fast heart rate occurs in the ventricles of the heart. Although a few seconds of VT may not result in permanent problems, longer periods are dangerous; and multiple episodes over a short period of time are referred to as an electrical storm. Short periods may occur without symptoms, or present with lightheadedness, palpitations, shortness of breath, chest pain, and decreased level of consciousness. Ventricular tachycardia may lead to coma and persistent vegetative state due to lack of blood and oxygen to the brain. Ventricular tachycardia may result in ventricular fibrillation (VF) and turn into cardiac arrest. This conversion of the VT into VF is called the degeneration of the VT. It is found initially in about 7% of people in cardiac arrest.

<span class="mw-page-title-main">Supraventricular tachycardia</span> Abnormally fast heart rhythm

Supraventricular tachycardia (SVT) is an umbrella term for fast heart rhythms arising from the upper part of the heart. This is in contrast to the other group of fast heart rhythms – ventricular tachycardia, which start within the lower chambers of the heart. There are four main types of SVT: atrial fibrillation, atrial flutter, paroxysmal supraventricular tachycardia (PSVT), and Wolff–Parkinson–White syndrome. The symptoms of SVT include palpitations, feeling of faintness, sweating, shortness of breath, and/or chest pain.

<span class="mw-page-title-main">AV nodal reentrant tachycardia</span> Medical condition

AV-nodal reentrant tachycardia (AVNRT) is a type of abnormal fast heart rhythm. It is a type of supraventricular tachycardia (SVT), meaning that it originates from a location within the heart above the bundle of His. AV nodal reentrant tachycardia is the most common regular supraventricular tachycardia. It is more common in women than men. The main symptom is palpitations. Treatment may be with specific physical maneuvers, medications, or, rarely, synchronized cardioversion. Frequent attacks may require radiofrequency ablation, in which the abnormally conducting tissue in the heart is destroyed.

Premature atrial contraction (PAC), also known as atrial premature complexes (APC) or atrial premature beats (APB), are a common cardiac dysrhythmia characterized by premature heartbeats originating in the atria. While the sinoatrial node typically regulates the heartbeat during normal sinus rhythm, PACs occur when another region of the atria depolarizes before the sinoatrial node and thus triggers a premature heartbeat, in contrast to escape beats, in which the normal sinoatrial node fails, leaving a non-nodal pacemaker to initiate a late beat.

Tachycardia-induced cardiomyopathy (TIC) is a disease where prolonged tachycardia or arrhythmia causes an impairment of the myocardium, which can result in heart failure. People with TIC may have symptoms associated with heart failure and/or symptoms related to the tachycardia or arrhythmia. Though atrial fibrillation is the most common cause of TIC, several tachycardias and arrhythmias have been associated with the disease.

Lown–Ganong–Levine syndrome (LGL) is a pre-excitation syndrome of the heart. Those with LGL syndrome have episodes of abnormal heart racing with a short PR interval and normal QRS complexes seen on their electrocardiogram when in a normal sinus rhythm. LGL syndrome was originally thought to be due to an abnormal electrical connection between the atria and the ventricles, but is now thought to be due to accelerated conduction through the atrioventricular node in the majority of cases. The syndrome is named after Bernard Lown, William Francis Ganong, Jr., and Samuel A. Levine.

<span class="mw-page-title-main">Lorcainide</span> Antiarrythmic agent

Lorcainide is a Class 1c antiarrhythmic agent that is used to help restore normal heart rhythm and conduction in patients with premature ventricular contractions, ventricular tachycardiac and Wolff–Parkinson–White syndrome. Lorcainide was developed by Janssen Pharmaceutica (Belgium) in 1968 under the commercial name Remivox and is designated by code numbers R-15889 or Ro 13-1042/001. It has a half-life of 8.9 +- 2.3 hrs which may be prolonged to 66 hrs in people with cardiac disease.

An accessory pathway is an additional electrical connection between two parts of the heart. These pathways can lead to abnormal heart rhythms or arrhythmias associated with symptoms of palpitations. Some pathways may activate a region of ventricular muscle earlier than would normally occur, referred to as pre-excitation, and this may be seen on an electrocardiogram. The combination of an accessory pathway that causes pre-excitation with arrhythmias is known as Wolff-Parkinson-White syndrome.

Re-entry ventricular arrhythmia is a type of paroxysmal tachycardia occurring in the ventricle where the cause of the arrhythmia is due to the electric signal not completing the normal circuit, but rather an alternative circuit looping back upon itself. There develops a self-perpetuating rapid and abnormal activation. Conditions necessary for re-entry include a combination of unidirectional block and slowed conduction. Circus movement may also occur on a smaller scale within the AV node, a large bypass tract is not necessary.

<span class="mw-page-title-main">Junctional ectopic tachycardia</span> Medical condition

Junctional ectopic tachycardia (JET) is a rare syndrome of the heart that manifests in patients recovering from heart surgery. It is characterized by cardiac arrhythmia, or irregular beating of the heart, caused by abnormal conduction from or through the atrioventricular node. In newborns and infants up to 6 weeks old, the disease may also be referred to as His bundle tachycardia or congenital JET.

Atrial tachycardia is a type of heart rhythm problem in which the heart's electrical impulse comes from an ectopic pacemaker in the upper chambers (atria) of the heart, rather than from the sinoatrial node, the normal origin of the heart's electrical activity. As with any other form of tachycardia, the underlying mechanism can be either the rapid discharge of an abnormal focus, the presence of a ring of cardiac tissue that gives rise to a circle movement (reentry), or a triggered rapid rhythm due to other pathological circumstances.

<span class="mw-page-title-main">Atrioventricular reentrant tachycardia</span> Medical condition

Atrioventricular reentrant tachycardia (AVRT), or atrioventricular reciprocating tachycardia, is a type of abnormal fast heart rhythm and is classified as a type of supraventricular tachycardia (SVT). AVRT is most commonly associated with Wolff–Parkinson–White syndrome, but is also seen in permanent junctional reentrant tachycardia (PJRT). In AVRT, an accessory pathway allows electrical signals from the heart's ventricles to enter the atria and cause earlier than normal contraction, which leads to repeated stimulation of the atrioventricular node.

<span class="mw-page-title-main">Arrhythmia</span> Group of medical conditions characterized by irregular heartbeat

Arrhythmias, also known as cardiac arrhythmias, heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adults – is called tachycardia, and a resting heart rate that is too slow – below 60 beats per minute – is called bradycardia. Some types of arrhythmias have no symptoms. Symptoms, when present, may include palpitations or feeling a pause between heartbeats. In more serious cases, there may be lightheadedness, passing out, shortness of breath, chest pain, or decreased level of consciousness. While most cases of arrhythmia are not serious, some predispose a person to complications such as stroke or heart failure. Others may result in sudden death.

<span class="mw-page-title-main">Automatic tachycardia</span> Medical condition

An automatic tachycardia is a cardiac arrhythmia which involves an area of the heart generating an abnormally fast rhythm, sometimes also called enhanced automaticity. These tachycardias, or fast heart rhythms, differ from reentrant tachycardias in which there is an abnormal electrical pathway which gives rise to the pathology. Most automatic tachycardias are supraventricular tachycardias (SVT). It is important to recognize an automatic tachycardia because the treatment will be different to that for a reentrant tachycardia. The most useful clue will be the presence of 'warm up' and 'cool down'. This means that whereas a reentrant tachycardia will both begin and end abruptly as cardiac conduction uses then ceases to use the accessory pathway, an automatic tachycardia will rise and fall gradually in rate as the automatic focus increases and decreases its automatic rate of electrical discharge.

<span class="mw-page-title-main">Rhythm interpretation</span>

Rhythm interpretation is an important part of healthcare in Emergency Medical Services (EMS). Trained medical personnel can determine different treatment options based on the cardiac rhythm of a patient. There are many common heart rhythms that are part of a few different categories, sinus arrhythmia, atrial arrhythmia, ventricular arrhythmia. Rhythms can be evaluated by measuring a few key components of a rhythm strip, the PQRST sequence, which represents one cardiac cycle, the ventricular rate, which is the rate at which the ventricles contract, and the atrial rate, which is the rate at which the atria contract.

References

  1. 1 2 Awtry EH, Jeon C, Ware MG (2006). "Tachyarrhythmias". Blueprints Cardiology (2nd ed.). Malden, Mass.: Blackwell. p. 93. ISBN   9781405104647.
  2. ↑ Thompson EG, Pai RK, eds. (2 June 2011). "Passing Out (Syncope) Caused by Arrhythmias". CardioSmart. American College of Cardiology. Archived from the original on 2020-06-13. Retrieved 2020-04-13.
  3. ↑ Kushner A, West WP, Pillarisetty LS (2020). "Virchow Triad". StatPearls. Treasure Island (FL): StatPearls Publishing. PMID   30969519 . Retrieved 2020-06-18.
  4. ↑ Kumar DR, Hanlin E, Glurich I, Mazza JJ, Yale SH (December 2010). "Virchow's contribution to the understanding of thrombosis and cellular biology". Clinical Medicine & Research. 8 (3–4): 168–172. doi:10.3121/cmr.2009.866. PMC   3006583 . PMID   20739582.
  5. ↑ "Supraventricular Tachycardias". The Lecturio Medical Concept Library. 9 September 2020. Retrieved 2 July 2021.
  6. ↑ Rangaraj VR, Knutson KL (February 2016). "Association between sleep deficiency and cardiometabolic disease: implications for health disparities". Sleep Medicine. 18: 19–35. doi:10.1016/j.sleep.2015.02.535. PMC   4758899 . PMID   26431758.
  7. ↑ Custer JW, Rau RE, Budzikowski AS, Cho CS (2008). Rottman JN (ed.). The Harriet Lane Handbook (18th ed.). Elsevier Health Sciences. ISBN   978-0-323-07688-3.
  8. ↑ Kantharia BK, Sharma M, Shah AN (17 October 2021). "Atrial Tachycardia: Practice Essentials, Background, Anatomy". MedScape. WebMD LLC.
  9. ↑ Fauci AS, Braunwald E, Kasper DL, Hauser SL, Longo DL, Jameson JL, Loscalzo J (2008). Harrison's Principles of Internal Medicine (17th ed.). New York: McGraw-Hill. ISBN   978-0-07-146633-2.
  10. 1 2 3 4 5 6 Neumar RW, Otto CW, Link MS, Kronick SL, Shuster M, Callaway CW, et al. (November 2010). "Part 8: adult advanced cardiovascular life support: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care". Circulation. 122 (18 Suppl 3): S729–S767. doi: 10.1161/CIRCULATIONAHA.110.970988 . PMID   20956224.
  11. ↑ Pieper SJ, Stanton MS (April 1995). "Narrow QRS complex tachycardias". Mayo Clinic Proceedings. 70 (4): 371–375. doi: 10.4065/70.4.371 . PMID   7898144.
  12. 1 2 3 4 Lucia A, Martinuzzi A, Nogales-Gadea G, Quinlivan R, Reason S (December 2021). "Clinical practice guidelines for glycogen storage disease V & VII (McArdle disease and Tarui disease) from an international study group". Neuromuscular Disorders. 31 (12): 1296–1310. doi:10.1016/j.nmd.2021.10.006. PMID   34848128.
  13. 1 2 3 Scalco RS, Chatfield S, Godfrey R, Pattni J, Ellerton C, Beggs A, Brady S, Wakelin A, Holton JL, Quinlivan R (July 2014). "From exercise intolerance to functional improvement: the second wind phenomenon in the identification of McArdle disease". Arquivos de Neuro-psiquiatria. 72 (7): 538–41. doi:10.1590/0004-282x20140062. PMID   25054987.
  14. 1 2 Wakelin A (2017). Living With McArdle Disease (PDF). International Assoc. of Muscle Glycogen Diseases (IAMGSD). p. 15.
  15. ↑ Barker RL, Burton JR, Zieve PD, eds. (2003). Principles of Ambulatory Medicine (Sixth ed.). Philadelphia, PA: Lippinocott, Wilkins & Williams. ISBN   0-7817-3486-X.
  16. ↑ Ahmed A, Pothineni NV, Charate R, Garg J, Elbey M, de Asmundis C, LaMeir M, Romeya A, Shivamurthy P, Olshansky B, Russo A, Gopinathannair R, Lakkireddy D (2022-06-21). "Inappropriate Sinus Tachycardia: Etiology, Pathophysiology, and Management: JACC Review Topic of the Week". Journal of the American College of Cardiology. 79 (24): 2450–2462. doi:10.1016/j.jacc.2022.04.019. ISSN   0735-1097. PMID   35710196.
  17. ↑ Peyrol M, Lévy S (June 2016). "Clinical presentation of inappropriate sinus tachycardia and differential diagnosis". Journal of Interventional Cardiac Electrophysiology. 46 (1): 33–41. doi:10.1007/s10840-015-0051-z. PMID   26329720. S2CID   23249973.
  18. ↑ Mitchell LB (January 2023). "Torsades de Pointes Ventricular Tachycardia". Merck Manual Profesional Edition. Retrieved 19 April 2019.
  19. ↑ Samie FH, Jalife J (May 2001). "Mechanisms underlying ventricular tachycardia and its transition to ventricular fibrillation in the structurally normal heart". Cardiovascular Research. 50 (2): 242–250. doi: 10.1016/S0008-6363(00)00289-3 . PMID   11334828.
  20. ↑ Srivathsan K, Ng DW, Mookadam F (July 2009). "Ventricular tachycardia and ventricular fibrillation". Expert Review of Cardiovascular Therapy. 7 (7): 801–809. doi:10.1586/erc.09.69. PMID   19589116. S2CID   207215117.
  21. ↑ "Types of Arrhythmia". National Heart, Lung, and Blood Institute (NHLBI). U.S. National Institutes of Health. July 1, 2011. Archived from the original on June 7, 2015.
  22. ↑ Oiseth S, Jones L, Maza E (11 August 2020). "Atrial Fibrillation". The Lecturio Medical Concept Library. Retrieved 3 July 2021.
  23. ↑ Katritsis DG (December 2018). "Catheter Ablation of Atrioventricular Nodal Re-entrant Tachycardia: Facts and Fiction". Arrhythmia & Electrophysiology Review. 7 (4): 230–231. doi:10.15420/aer.2018.7.4.EO1. PMC   6304791 . PMID   30588309.
  24. ↑ Rosen KM (March 1973). "Junctional tachycardia. Mechanisms, diagnosis, differential diagnosis, and management". Circulation. 47 (3): 654–664. doi:10.1161/01.CIR.47.3.654. PMID   4571060.
  25. ↑ Elsevier, Dorland's Illustrated Medical Dictionary, Elsevier.
  26. ↑ Merriam-Webster, Merriam-Webster's Medical Dictionary, Merriam-Webster.
  27. 1 2 Wolters Kluwer, Stedman's Medical Dictionary, Wolters Kluwer.
  28. ↑ Houghton Mifflin Harcourt, The American Heritage Dictionary of the English Language, Houghton Mifflin Harcourt.
  29. ↑ Merriam-Webster, Merriam-Webster's Collegiate Dictionary, Merriam-Webster, archived from the original on 2020-10-10, retrieved 2017-07-22.
  30. ↑ Merriam-Webster, Merriam-Webster's Unabridged Dictionary, Merriam-Webster, archived from the original on 2020-05-25, retrieved 2017-07-22.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.