Jack’s Health Part C: Atrial Fibrillation (Afib)

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Jack states it feels like his heart is racing and he can’t catch his breath. His Radial pulse is 130 BPM (irregular).

Jack is taken to the emergency department as per his family physician’s recommendation and is diagnosed with new onset of atrial fibrillation.

He is admitted to hospital with a cardiologist and endocrinologist referral.

An Overview of Atrial Fibrillation

What is Atrial Fibrillation?

  • Irregular & often rapid heart rate
  • Can increase risk of stroke, heart failure, other heart-related complications
  • The two atria beat chaotically & irregularly – out of coordination with the two ventricles
  • Episodes may come & go, or does not go away requiring treatment
  • Is not life-threatening but a serious medical condition that may require emergency treatment
Anatomical description of the heart showing all important features for blood flow.
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Complications may arise

Complications of Afib

  • Major concern is the potential to develop blood clots in the atria
  • These clots may circulate to other organs & lead to ischemia
  • May weaken the heart and lead to heart failure

Cardiac Conduction

In a normal heart rhythm, a tiny cluster of cells at the sinus (SA) node sends out an electrical signal. The signal then travels through the atria to the atrioventricular (AV) node and passes into the ventricles, causing them to contract and pump out blood. In atrial fibrillation, electrical signals fire from multiple locations in the atria (typically pulmonary veins), causing them to beat chaotically. Since the atrioventricular (AV) node doesn’t prevent all of these chaotic signals from entering the ventricles, your heart will beat faster and more irregularly than normal.

Anatomical description of the heart showing all important features for oxygen flow.
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Symptoms for Atrial Fibrillation

  • The two atria beat chaotically & irregularly: out of coordination with the two ventricles
  • Palpitations, sensations of a racing, uncomfortable, irregular heartbeat or a ‘flip-flopping’ in the chest
  • Weakness
  • Reduced ability to exercise
  • Fatigue
  • Lightheadedness
  • Dizziness
  • Shortness of breath
  • Chest pain

Which of these symptoms has Jack experienced?

EKG/ECG readings of Atrial Fibrillations.
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How often can Atrial Fibrillation occur?

Atrial Fibrillation may be:

  • Occasional: paroxysmal A-fib comes and goes, usually lasting for a few minutes to hours. May last up to a week and happen repeatedly.
  • Persistent: heart rhythm does not go back to normal on its own. Will need treatment; medication or electrical shock to restore normal heart rhythm.
  • Long-standing persistent: continuous and lasts longer than 12 months.
  • Permanent: normal heart rhythm cannot be restored.  Requires medication to control heart rate and to prevent clots.

Possible Causes of Atrial Fibrillation

Abnormalities or damage to the heart’s structure are the most common cause of A-fib.

Possible causes of A-fib include:

  • High blood pressure
  • Heart attack
  • Coronary artery disease
  • Abnormal heart valves
  • Heart defects (congenital)
  • Overactive thyroid gland
  • Metabolic imbalance
  • Exposure to stimulants – medications, caffeine, tobacco, alcohol
  • Sick sinus syndrome – improper functioning of the heart’s natural pacemaker
  • Lung diseases
  • Previous heart surgery
  • Viral infections
  • Stress due to surgery, pneumonia or other illnesses
  • Sleep apnea

Which of these risk factors does Jack have?

Jack treats his Afib with medication

Rate Control Medications Rhythm Control Medications
Beta blockers (Metroprolol or Bisoprolol) Amiodarone (Cordarone)

Rate Control: Slows the heart rate by blocking some of the incoming electrical signals in the atria and preventing them from being transmitted to the ventricles

Rhythm Control: Maintains sinus rythym

IV form of the drug Metoprolol.
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Jack undergoes procedures for Rhythm Control

Electrical Cardioversion: delivering a shock to the heart, like defibrillation but a smaller amount of electricity.  Cardioversion is a short-term solution.  In most patients, the A-fib comes back.

Catheter Ablation: inserting thin wires into the veins in your groin or neck. The tip of the wire is directed towards the area in your heart that is firing irregular impulses. Once in position, a small jolt of radiofrequency electrical current is delivered to burn out the tiny areas.

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Multi-Course Case Studies in Health Sciences (Version 2) Copyright © 2021 by Laura Banks; Elita Partosoedarso; Manon Lemonde; Robert Balogh; Adam Cole; Mika Nonoyama; Otto Sanchez; Sarah West; Sarah Stokes; Syed Qadri; Robin Kay; Mary Chiu; and Lynn Zhu is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License, except where otherwise noted.

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