Atrial fibrillation

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Scheme of chaotically arising excitations in the heart atria during atrial fibrillation Animation of impulse propagation during atrial fibrillation Atrial fibrillation (top), Physiological ECG (bottom): red arrow shows the location of the missing P wave Atrial fibrillation and left bundle branch block - absent P waves, irregular RR interval, QRS complex is abnormal due to bundle branch block Atrial fibrillation (atrial fibrillation, FS, FiS) is the most common arrhythmia worldwide. It is a tachyarrhythmia with disordered atrial activity with absolute irregularity of impulse transmission to the ventricles, which is associated with increased morbidity and mortality.Scheme of chaotically arising excitations in the heart atria during atrial fibrillation Animation of impulse propagation during atrial fibrillation Atrial fibrillation (top), Physiological ECG (bottom): red arrow shows the location of the missing P wave Atrial fibrillation and left bundle branch block - absent P waves, irregular RR interval, QRS complex is abnormal due to bundle branch block Atrial fibrillation (atrial fibrillation, FS, FiS) is the most common arrhythmia worldwide. It is a tachyarrhythmia with disordered atrial activity with absolute irregularity of impulse transmission to the ventricles, which is associated with increased morbidity and mortality.

Atrial fibrillation:


Atrial fibrillation 2:



FS Types[edit | edit source]

We distinguish 4 basic types of FS:[1]

  1. first documented attack;
  2. paroxysmal - FS occurs in attacks that end spontaneously, usually within 48 hours,; or episodes lasting up to 7 days terminated by cardioversion;
  3. persistent – AF does not end spontaneously, it is necessary to perform pharmacological or electrical cardioversion;
  4. permanent - neither cardioversion nor antiarrhythmic treatment leads to the establishment of sinus rhythm.

Sinus Rhythm:



Etiopathogenesis[edit | edit source]

The occurrence and maintenance of atrial fibrillation are usually caused by rapid bursts of atrial extrasystoles, most often coming from the pulmonary veins, and structural changes in the atrial musculature, which occurs due to aging. heart diseases (IHD, heart failure, valvular defects).

With mitral valve defects, there is an overload of the left atrium. Similarly, with arterial hypertension, there is hypertrophy of the left ventricle and, subsequently, a failure of its filling and a rise in pressure in the left atrium.

Mezi predisponující faktory řadíme:

Atrial fibrillation also occurs more often in patients with COPD, obstructive sleep apnea, chronic kidney disease, diabetes mellitus, obesity , increased alcohol consumption, but also during regular intensive exercise.

Symptoms[edit | edit source]

The atrium does not contract, so it is not used in the last phase of diastole, when blood is actively pushed into the ventricle. Symptoms of atrial fibrillation are based on a decrease in cardiac output:

Atrial fibrillation can be asymptomatic and then the first manifestation is a systemic embolization.

Diagnostika[edit | edit source]

Pulz je nepravidelný. Diagnostika se opírá o EKG. Na EKG pozorujeme tyto abnormality:

  • chybějí vlny P – jsou nahrazeny nepravidelnou izoelektrickou linií nebo fibrilačními vlnkami;
  • komplexy QRS jsou štíhlé;
  • R–R interval je nepravidelný → nepravidelná komorová akce;
  • srdeční frekvence se pohybuje mezi 80–180/min.

Atrial fibrillation is characterized by ``asynchronous contraction of atrial muscle fibers (``lack of P waves). A large number of impulses are generated in the atrial myocardium, which travel to the AV node. The rate of the atria tends to be ``300-600/min, while the rate of the ventricles is 80-180/min. The AV node blocks the transfer of most atrial contractions to the ventricles. It thus protects the chambers from their exhaustion. The AV node works on the "all or nothing" principle → only impulses with the appropriate intensity pass through. Such excitations occur irregularly in the atria, so that the ventricles also contract irregularly (R–R interval is irregular; heart rate varies between 80–180/min). The transition from the atria to the ventricles takes place physiologically via the AV node and the bundle of Hiss (QRS complexes are slender).

At the first occurrence of atrial fibrillation, it is necessary to rule out possible causes of tachycardia, e.g. AMI, PE, thyrotoxicosis, hypokalemia, [[ Anemia], infection.

Differential diagnosis[edit | edit source]

In terms of differential diagnosis, it is necessary to differentiate:

Komplikace[edit | edit source]

  • Creation of a mural thrombus' and subsequent embolization (primarily to the CNS). Thrombi most often form in the ears.
  • Tachycardia cardiomyopathy, left ventricular dysfunction, heart failure
  • Cognitive impairment and vascular dementia. They can also develop in anticoagulated patients with AF. Lesions in the white matter of the brain are seen more often in patients with AF than in patients without AF.

Treatment[edit | edit source]

Manual Defibrillator Position of "hands free" electrodes during external electrical cardioversion In the treatment of atrial fibrillation, we try to:

  1. establishing and maintaining an optimal heart rate' (ventricular rate);
  2. establishment and maintenance of sinus rhythm';
  3. elimination of thromboembolic complications'.

Establishing and maintaining an optimal heart rate[edit | edit source]

Atrial fibrillation is classified among the so-called tachyarrhythmias. The heart rate reaches values of up to 180/min.

Medicines with a negative chronotropic effect are used to slow down the heart rate.[2]

  • β-blockers – negative inotropic, chronotropic and dromotropic effect. They are not suitable for patients with heart failure, AV block or sick sinus syndrome. Their advantage is the rapid onset of effect. The most frequently used preparations are metoprolol, atenolol and bisoprolol.
  • Calcium channel blockers - negative inotropic, chronotropic and dromotropic effect, not suitable for patients with heart insufficiency, AV-block or sick sinus syndrome . Their advantage is the rapid onset of effect. The most frequently used drugs are diltiazem and verapamil.
  • Digoxin – positive inotropic effect, negative dromotropic and negative chronotropic effect, is suitable for elderly patients with heart insufficiency and little physical activity. Its disadvantage is the slow onset of effect.

Establishing and maintaining sinus rhythm[edit | edit source]

Establishment of sinus rhythm

We use pharmacological or electrical cardioversion to establish sinus rhythm:

  • Chemical (pharmacological) cardioversion: propafenone, amiodarone (to perform chemical cardioversion, it is necessary to hospitalize the patient and continuously monitor the ECG).[2]
  • Electrical cardioversion (external or internal): external electrical cardioversion can be performed on an outpatient basis (without the need for hospitalization). Using a biphasic 'synchronized (with QRS so that the discharge does not enter the vulnerable phase and does not cause ventricular fibrillation) discharge, we choose an energy of 70-170 J. Electrical cardioversion is more effective and safer compared to chemical cardioversion.[3]

Cardioversion can only be performed with the prevention of systemic embolization. The only exception is hemodynamically intolerable arrhythmias. Alternatively, thrombus in the left atrial appendage can be ruled out by TEE and anticoagulation is started only after cardioversion.

Maintenance of sinus rhythm

We mainly use antiarrhythmics class Ic (propafenone, flecainide) and class III (amiodarone, sotalol).

Katetrová ablace[4][edit | edit source]

V případě neúspěchu farmakologické léčby lze provést tzv. neselektivní radiofrekvenčí ablaci AV uzlu s následnou implantací kardiostimulátoru či selektivní radiofrekvenční ablaci.

In the case of non-selective radiofrequency ablation, we introduce the ablation catheter into the right heart via the femoral vein. A radiofrequency current is applied to the area of the AV junction, thereby artificially inducing bradycardia as a result of complete AV blockade with preserved stable junctional rhythm. We then implant a heart pacemaker. This procedure is performed only in highly symptomatic patients resistant to pharmacological treatment.

The essence of selective radiofrequency ablation is the isolation of pulmonary veins after the introduction of a catheter into the right atrium and subsequent transseptal puncture. Due to the higher risk of complications, this method is mainly used in patients with symptomatic drug-resistant paroxysmal atrial fibrillation.[5]

Elimination of thromboembolic complications[edit | edit source]

The risk of thromboembolic complications is evaluated according to the CHA2DS2-VASc score. In patients with a high risk of thromboembolism (men with a score ≥ 2, women ≥ 3), anticoagulation therapy is indicated.[6] For patients with medium risk (men ≥ 1, women ≥ 2), we use treatment according to the patient's preferences. NOACs are used as first-line drugs, followed by warfarin.

The HAS-BLED score is used to determine the risk of bleeding complications during anticoagulant treatment in patients with AF. In patients with an increased risk of bleeding, a reduced dose of anticoagulants is used.

Antiplatelet therapy is not recommended unless there is another indication, e.g. CAD, etc.

An alternative to the prevention of thromboembolic complications is the use of obliteration of the left atrial appendage with an occluder or surgical ligation of the atrial appendage.

Links[edit | edit source]

Related Articles[edit | edit source]

External links[edit | edit source]

Reference[edit | edit source]

  1. {{#switch: article |book = Incomplete publication citation. ŠIHÁK, R and P HEINC46. Also available from <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>.  |collection = Incomplete citation of contribution in proceedings. ŠIHÁK, R and P HEINC. 46. Also available from <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. {{ #if: |978-80-7262-438-6} } |article = Incomplete article citation.  ŠIHÁK, R and P HEINC. Recommendations for the treatment of patients with atrial fibrillation. Cor et Vasa [online]. 46, year 46, also available from <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. ISSN 1803-7712.  |web = Incomplete site citation. ŠIHÁK, R and P HEINC. ©46. <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. |cd = Incomplete carrier citation. ŠIHÁK, R and P HEINC. ©46.  |db = Incomplete database citation. ©46. <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. |corporate_literature = Incomplete citation of company literature. ŠIHÁK, R and P HEINC. 46. Also available from <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. legislative_document = Incomplete citation of legislative document.  46. Also available from URL <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. ISSN 1803-7712.
  2. a b {{#switch: article |book = Incomplete publication citation. LUKL, Jan2001. Also available from <http://www.solen.cz/pdfs/int/2001/01/03.pdf>.  |collection = Incomplete citation of contribution in proceedings. LUKL, Jan. 2001. Also available from <http://www.solen.cz/pdfs/int/2001/01/03.pdf>. {{ #if: |978-80-7262-438-6} } |article = Incomplete article citation.  LUKL, Jan. Treatment of atrial fibrillation and flutter. 2001, year 2001, well. 1, also available from <http://www.solen.cz/pdfs/int/2001/01/03.pdf>. ISSN 1803-5256.  |web = Incomplete site citation. LUKL, Jan. ©2001. <http://www.solen.cz/pdfs/int/2001/01/03.pdf>. |cd = Incomplete carrier citation. LUKL, Jan. ©2001.  |db = Incomplete database citation. ©2001. <http://www.solen.cz/pdfs/int/2001/01/03.pdf>. |corporate_literature = Incomplete citation of company literature. LUKL, Jan. 2001. Also available from <http://www.solen.cz/pdfs/int/2001/01/03.pdf>. legislative_document = Incomplete citation of legislative document.  2001. Also available from URL <http://www.solen.cz/pdfs/int/2001/01/03.pdf>. ISSN 1803-5256.
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  4. {{#switch: book |book = Incomplete publication citation. CZECH, Richard, et al. Intern. Prague : Triton, 2010. 855 s. pp. 480-481. 978-80-7262-438-6. |collection = Incomplete citation of contribution in proceedings. CZECH, Richard, et al. Intern. Prague : Triton, 2010. 855 s. pp. 480-481. {{ #if: 978-80-7387-423-0 |978-80-7262-438-6} } |article = Incomplete article citation.  CZECH, Richard, et al. 2010, year 2010, pp. 480-481,  |web = Incomplete site citation. CZECH, Richard, et al. Triton, ©2010.  |cd = Incomplete carrier citation. CZECH, Richard, et al. Triton, ©2010.  |db = Incomplete database citation. Triton, ©2010.  |corporate_literature = CZECH, Richard, et al. Intern. Prague : Triton, 2010. 855 s. 978-80-7262-438-6} }, s. 480-481.
  5. {{#switch: article |book = Incomplete publication citation. ŠIHÁK, R and P HEINC46. Also available from <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>.  |collection = Incomplete citation of contribution in proceedings. ŠIHÁK, R and P HEINC. 46. Also available from <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. {{ #if: |978-80-7262-438-6} } |article = Incomplete article citation.  ŠIHÁK, R and P HEINC. Recommendations for the treatment of patients with atrial fibrillation. Cor et Vasa [online]. 46, year 46, also available from <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. ISSN 1803-7712.  |web = Incomplete site citation. ŠIHÁK, R and P HEINC. ©46. <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. |cd = Incomplete carrier citation. ŠIHÁK, R and P HEINC. ©46.  |db = Incomplete database citation. ©46. <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. |corporate_literature = Incomplete citation of company literature. ŠIHÁK, R and P HEINC. 46. Also available from <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. legislative_document = Incomplete citation of legislative document.  46. Also available from URL <https://www.kardio-cz.cz/data/upload/Doporuceni_pro_lecbu_pacient_s_fibrilaci_sini_2004.pdf>. ISSN 1803-7712.

References[edit | edit source]

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  Incomplete publication citation. VACHEK, Jan, Vit MÓTAŇ and Oscar ZAKIYANOV, et al. Acute conditions in internal medicine. Maxdorf, 2018. 978-80-7262-438-6.

|collection =

  Incomplete citation of contribution in proceedings. VACHEK, Jan, Vit MÓTAŇ and Oscar ZAKIYANOV, et al. Acute conditions in internal medicine. Maxdorf, 2018. {{
  #if: 9788073455507 |978-80-7262-438-6} }
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  Incomplete article citation.  VACHEK, Jan, Vit MÓTAŇ and Oscar ZAKIYANOV, et al. 2018, year 2018, 

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|collection =

  Incomplete citation of contribution in proceedings. CZECH, Richard, et al. Intern. Prague : Triton, 2015. 897 s. pp. 98-102. {{
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  Incomplete article citation.  CZECH, Richard, et al. 2015, year 2015, pp. 98-102, 

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  Incomplete site citation. CZECH, Richard, et al. Triton, ©2015. 

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