Cardiovascular 3 Flashcards
What are arrhythmias?
Abnormal heart rhythms due to issues such as congenital anomalies, scar tissue, or electrolyte imbalances.
what are the 2 types of arrhythmias
Tachyarrhythmias (fast heart rhythms)
Bradyarrhythmias (slow heart rhythms)
What are examples of tachyarrhythmias?
Sinus tachycardia
Supraventricular tachycardia (SVT)
Atrial flutter
Atrial fibrillation (AF)
Ventricular tachycardia (VT)
What are examples of bradyarrhythmias?
Sinus bradycardia
Sick sinus syndrome
Heart block (various degrees)
Ventricular escape rhythm
What are the causes of arrhythmias?
Congenital anomalies
Scar tissue (e.g., post-MI)
Electrolyte imbalances
Abnormal impulse generation in the atria or AV node
How does supraventricular tachycardia (SVT) differ from sinus tachycardia?
Both are fast rhythms, but SVT originates above the ventricles outside the sinus node, making it indistinguishable from sinus tachycardia without an ECG.
What is ventricular tachycardia and why is it dangerous?
Originates in the ventricles.
If highly irregular, it can lead to ventricular fibrillation and cardiac arrest.
How does cardioversion work for tachyarrhythmias?
Delivers a carefully timed electrical shock to reset the heart rhythm.
Works well for some arrhythmias but often fails in chronic atrial fibrillation (AF).
How does bradyarrhythmia affect cardiac output?
Slow rhythm → low cardiac output due to insufficient heart rate.
Contrast: Tachyarrhythmia reduces stroke volume, leading to low cardiac output as well
How can one assess the heart rhythm?
By evaluating the pulse for its rate, rhythm, and character
What is the normal rhythm generation of the heart called?
sinus rhythm
What is the consequence of a drop in cardiac output during arrhythmias?
it can lead to syncope, or temporary reduction in brain perfusion
What is the role of anticoagulants in the management of arrhythmias?
Anticoagulants like warfarin ensure proper blood thickness, while DOACs offer more stable anticoagulation effects but are less reversible.
What class of drugs is used for rate control in atrial fibrillation?
Antiarrhythmic medications and beta blockers.
What are the four classes of antiarrhythmic medications and their mechanisms?
Class I: Sodium channel blockers - stabilize cell membranes
Class II: Beta blockers - reduce heart rate
Class III: Potassium channel blockers - prolong repolarization
Class IV: Calcium channel blockers - reduce conduction through the AV node
What are some common side effects and interactions of cardiovascular medications?
Dry mouth, angioedema, hypokalemia, and interactions with other drugs like ibuprofen.
What can cause hypokalemia in patients taking certain medications?
diuretics, which can lower potassium levels and increase the toxicity of drugs like digoxin.
What specific local anesthetic should be avoided in patients taking antiarrhythmic medication?
Bupivacaine, as it is cardiotoxic.
What should healthcare providers remember when prescribing medications to patients with cardiovascular conditions?
The potential interactions and side effects of the drugs, as well as the patient’s overall health status.
Why is it important to maintain an appropriate level of anticoagulation?
To prevent complications such as thrombosis and to ensure safe management during procedures.
Hypoglycemia and hypoxia can also lead to loss of consciousness, even with sufficient blood flow.
What is the difference between bradyarrhythmias and tachyarrhythmias?
Bradyarrhythmias involve a low heart rate leading to low cardiac output, while tachyarrhythmias involve a high heart rate that can also reduce stroke volume.
What is atrial fibrillation?
A condition where the heart’s rhythm originates in the Atria rather than the sinoatrial node, leading to chaotic electrical activity and an irregular pulse, increasing stroke risk
Why does AF increase stroke risk?
Chaotic atrial contraction → stagnant blood → clot formation.
If the clot enters systemic circulation, it can cause an embolic stroke.
