ADVANCED ARRHYTHMIAS FINAL EXAM 2025-2026
QUESTIONS AND CORRECT ANSWERS CURRENTLY
TESTING COMPLETE QUESTIONS WITH DETAILED
VERIFIED ANSWERS WITH RATIONALES /ALREADY
GRADED A+
Explain the mechanism of "Increased Automaticity"-ANSWER-
Occurs when a specific area of the cardiac tissue depolarises
faster than the SA node, causing focal arrhythmia.
Explain the mechanism of "Re–entry"-ANSWER-Normally, the
AP travels through the myocardium via "fast" and "slow"
pathways. In re–entry, the impulse finds the normal "fast"
pathway refractory and is redirected to the "slow" pathway. It
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,continues both distally and retrograde up the "fast" pathway
and re–enters the loop.
Why is the SA node called the pacemaker of the heart?-
ANSWER-The SA node contains special myocytes which
depolarise faster than other cardiac tissue. This sets the pace
for the other cells.
Explain the mechanism of "Triggered Activity"-ANSWER-
Abnormally high–amplitude oscillations in the myocardium
lead to early triggering of an AP.
What is the most common mechanism of bradyarrhythmia?-
ANSWER-The SA node slows down or fails, causing the other
myocytes to take over the pacemaking role. A similar problem
can occur in the AV node.
What are the risk factors for tachyarrhythmias?-ANSWER-–
Previous MI
– LV aneurysm
– Valve disease
– Stimulant drugs
– Psychological (fear, pain, anxiety)
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,What are the treatments for primary tachycardia?-ANSWER-–
Vagal maneuvers
– Drugs that block the AV node
– Antiarrhythmic drugs
– Electrical cardioversion
– Ablation of re–entry circuits
Explain the causes of Sinus Tachycardia.-ANSWER-Generally a
physiological response (normal). It originates in the SA node.
What is the difference between 'ectopic' and 'multifocial'
tachycardia?-ANSWER-Ectopic tachycardia originates in a
single area of the atrium and is characterised by early ectopic
beats.
Multifocal tachycardia originates in multiples atrial areas and
shows an irregularly irregular rhythm on ECG
Explain Atrial Fibrilation, and why is it so serious?-ANSWER-In
AF, the atria fibrillate at 400–600 bpm. The ECG shows a
indiscernible P wave and highly irregular beat.
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, AF is dangerous because the high bpm produces no effective
contraction and can also cause thrombi to form.
Describe the cause of atrial flutter and how it appears on ECG.-
ANSWER-Atrial flutter is caused by a large re–entry circuit in
the atrium. It shows a characteristic "sawtooth" appearance
on the ECG.
Outline the important features of Ventricular Tachycardia, and
why is it dangerous.-ANSWER-A disturbance in the ventricular
myocytes, e.g. from prior MI or ischaemia, is the main cause
of VT. The ECG shows very wide QRS complexes which
indicate slow repolarisation.
VT is dangerous because it can degenerate into ventricular
fibrillation or sudden cardiac death.
What are the main causes of heart block?-ANSWER-– Increased
vagal tone
– Decreased sympathetic tone
– Beta blockers
– Calcium channel blockers
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QUESTIONS AND CORRECT ANSWERS CURRENTLY
TESTING COMPLETE QUESTIONS WITH DETAILED
VERIFIED ANSWERS WITH RATIONALES /ALREADY
GRADED A+
Explain the mechanism of "Increased Automaticity"-ANSWER-
Occurs when a specific area of the cardiac tissue depolarises
faster than the SA node, causing focal arrhythmia.
Explain the mechanism of "Re–entry"-ANSWER-Normally, the
AP travels through the myocardium via "fast" and "slow"
pathways. In re–entry, the impulse finds the normal "fast"
pathway refractory and is redirected to the "slow" pathway. It
1|Page
,continues both distally and retrograde up the "fast" pathway
and re–enters the loop.
Why is the SA node called the pacemaker of the heart?-
ANSWER-The SA node contains special myocytes which
depolarise faster than other cardiac tissue. This sets the pace
for the other cells.
Explain the mechanism of "Triggered Activity"-ANSWER-
Abnormally high–amplitude oscillations in the myocardium
lead to early triggering of an AP.
What is the most common mechanism of bradyarrhythmia?-
ANSWER-The SA node slows down or fails, causing the other
myocytes to take over the pacemaking role. A similar problem
can occur in the AV node.
What are the risk factors for tachyarrhythmias?-ANSWER-–
Previous MI
– LV aneurysm
– Valve disease
– Stimulant drugs
– Psychological (fear, pain, anxiety)
2|Page
,What are the treatments for primary tachycardia?-ANSWER-–
Vagal maneuvers
– Drugs that block the AV node
– Antiarrhythmic drugs
– Electrical cardioversion
– Ablation of re–entry circuits
Explain the causes of Sinus Tachycardia.-ANSWER-Generally a
physiological response (normal). It originates in the SA node.
What is the difference between 'ectopic' and 'multifocial'
tachycardia?-ANSWER-Ectopic tachycardia originates in a
single area of the atrium and is characterised by early ectopic
beats.
Multifocal tachycardia originates in multiples atrial areas and
shows an irregularly irregular rhythm on ECG
Explain Atrial Fibrilation, and why is it so serious?-ANSWER-In
AF, the atria fibrillate at 400–600 bpm. The ECG shows a
indiscernible P wave and highly irregular beat.
3|Page
, AF is dangerous because the high bpm produces no effective
contraction and can also cause thrombi to form.
Describe the cause of atrial flutter and how it appears on ECG.-
ANSWER-Atrial flutter is caused by a large re–entry circuit in
the atrium. It shows a characteristic "sawtooth" appearance
on the ECG.
Outline the important features of Ventricular Tachycardia, and
why is it dangerous.-ANSWER-A disturbance in the ventricular
myocytes, e.g. from prior MI or ischaemia, is the main cause
of VT. The ECG shows very wide QRS complexes which
indicate slow repolarisation.
VT is dangerous because it can degenerate into ventricular
fibrillation or sudden cardiac death.
What are the main causes of heart block?-ANSWER-– Increased
vagal tone
– Decreased sympathetic tone
– Beta blockers
– Calcium channel blockers
4|Page
