Cardiology Heart Block Quiz

Questions and Answers

What does the white lead represent in this context?

Chocolate

Grass

The heart

Snow (correct)

What is the characteristic feature that needs to be assessed in a client with atrial fibrillation?

Irregular rate at the apical pulse (correct)

Comparing the apical and radial pressures

Pulse quality at the radial site

Regular pulse at the apical site

Where is the brown lead positioned according to the description?

In the centre close to the heart (correct)

On the left side next to the black lead

Above the green lead

Above the white lead

Which lead is positioned above the green lead?

White lead Signup and view all the answers

If the nurse notes regular QRS complexes with no P waves and a ventricular rate of 50 bpm, which part of the cardiac conduction system is likely affected?

Sinoatrial (SA) node Signup and view all the answers

What does a pulse deficit indicate in a clinical assessment?

Difference between apical and radial pulse rates Signup and view all the answers

Which lead is situated on the left side of the heart in the given arrangement?

Black lead Signup and view all the answers

What is the color representation of the chocolate lead?

Brown Signup and view all the answers

What characterizes Type 1 second-degree AV block?

PR interval elongation until a QRS complex is missed Signup and view all the answers

In the provided rhythm strip, what does a normal P wave indicate?

Normal atrial depolarization Signup and view all the answers

What does the presence of a pacer spike before a P wave suggest?

Atrial pacing Signup and view all the answers

Which of the following best describes the QRS complex in the context provided?

Narrow and normal, 0.06 seconds Signup and view all the answers

What does a variable PR interval in the rhythm strip indicate?

Possible second-degree AV block Signup and view all the answers

In the context of the rhythm strips, what implication does an irregular rhythm possess?

Possible electrical conduction issues Signup and view all the answers

What is indicated by a QT interval of 0.28 seconds?

Normal ventricular repolarization Signup and view all the answers

Which of the following statements is true for a third degree AV block?

There is a complete dissociation between atrial and ventricular activity Signup and view all the answers

What happens to the order of contraction in ventricular pacing?

Right ventricle contracts first followed by the left Signup and view all the answers

How many pacemaker leads are used in atrioventricular pacing?

One lead in the right atrium and one in the right ventricle Signup and view all the answers

What is a distinguishing feature of biventricular pacing on an ECG?

Two ventricular pacing spikes may be observed Signup and view all the answers

Which type of pacing allows for regular atrial and ventricular rhythm?

Atrioventricular pacing Signup and view all the answers

Which statement is true regarding demand pacing?

It is the most common type of implanted pacemaker. Signup and view all the answers

In ventricular pacing, what typically occurs with atrial activity?

Atrial activity is occasionally absent. Signup and view all the answers

What is the purpose of biventricular pacing?

To treat heart failure through cardiac resynchronization therapy Signup and view all the answers

What characterizes the pacemaker spikes in atrioventricular pacing?

A spike before both the P wave and QRS complex Signup and view all the answers

What happens to atrial contractions in third degree heart block?

They occur normally but are not followed by ventricular contractions. Signup and view all the answers

What characterizes the electrical conduction in complete heart block?

Electrical signals are blocked below the AV node. Signup and view all the answers

Which of the following best describes the relationship between P waves and QRS complexes in third degree heart block?

There are more P waves than QRS complexes. Signup and view all the answers

What is a potential treatment for patients with third degree heart block?

Counseling in the form of a pacemaker. Signup and view all the answers

How do the ventricles generate signals in third degree heart block?

Using an escape mechanism from within the ventricle. Signup and view all the answers

What does the term 'escape mechanism' refer to in the context of third degree heart block?

The ability of ventricles to generate their own signals. Signup and view all the answers

In third degree heart block, how do P waves relate to the overall electrical activity?

P waves provide no information about ventricular activity. Signup and view all the answers

Which characteristic is NOT typical of third degree heart block?

Atrial contractions are completely absent. Signup and view all the answers

What is indicated by a down sloping depression of the ST segment of 1mm or more?

Myocardial ischemia Signup and view all the answers

What is the range of delay at the AV node expressed in milliseconds?

120 to 200 ms Signup and view all the answers

What characterizes heart block?

Blockage of electrical signals between atria and ventricles Signup and view all the answers

What does the pause at the AV node allow in the heart's conduction process?

Atrial contraction and emptying Signup and view all the answers

How is heart block categorized?

By degree of severity Signup and view all the answers

In Normal Sinus Rhythm, how does the timing of the P wave compare to the QRS complex?

The P wave waits for the QRS complex Signup and view all the answers

What happens to electrical signals during heart block?

They are partially or totally blocked Signup and view all the answers

In first-degree AV Block, what happens to the P wave's behavior in relation to the QRS complex?

P wave is present but delayed Signup and view all the answers

Study Notes

Myocardial Ischemia and Heart Block

Downsloping depression of the ST segment by 1mm or more indicates myocardial ischemia.
Strain does not cause ST segment depression, while ischemia can cause ST elevation.

Normal Electrical Conduction in the Heart

Electrical conduction begins at the sinoatrial (SA) node, travels to the atrioventricular (AV) node after a delay of 120 to 200 milliseconds (PRI).
The His-Purkinje system distributes signals to left and right bundles, leading to ventricular contraction.
AV node delay allows atria to contract and empty before ventricles contract.

Heart Block Overview

Heart block is an arrhythmia leading to bradycardia caused by a delay in conduction between atria and ventricles.
Classified into 1st, 2nd, and 3rd degree based on severity.

Normal Sinus Rhythm (NSR)

In NSR, the P wave (atria) waits for the QRS complex (ventricles) to arrive on time every cycle.

First Degree Heart Block

P wave is consistently followed by QRS complex with a constant PR interval.
Indicates injury that can progress rapidly to more severe heart blocks.
Sometimes requires a pacemaker for management.

Third Degree Heart Block (Complete AV Block)

Complete disconnection between P waves and QRS complexes; each has its own rhythm.
Atria contract normally but transmit no signals to the ventricles.
Ventricles may generate their signals through an escape mechanism, leading to slower heartbeats.

Pacing Mechanisms

Ventricular Pacing: Pacemaker lead in right ventricle causes wide QRS complexes; atrial activity may be absent.
Atrioventricular Pacing: Sequential triggering of atrial then ventricular contraction with visible pacing spikes before both P wave and QRS complex.
Biventricular Pacing: Both right and left ventricles are paced, used for treating heart failure. May have dual spikes on the ECG.
Demand Pacing: Common type of pacemaker, with multiple leads placed accordingly to ensure effective pacing.

Atrial Fibrillation Assessment

Characterized by assessing apical pulse for irregular rate paired with palpation of the radial pulse for a pulse deficit.

Clinical Scenario Questions

Question 1: For atrial fibrillation, check apical pulse for irregularity and radial pulse for pulse deficit (Correct: a).
Question 2: Slow regular pulse with no P waves suggests a problem at the sinoatrial (SA) node (Correct: c).
Rhythm Interpretation:
- A rhythm strip displaying PR intervals increasing and then dropping indicates Type 1 second-degree AV block (Correct: b).
- A rhythm with a pacer spike only before the P wave indicates atrial pacing (Correct: b).

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on heart block and myocardial ischemia. This quiz covers essential concepts such as the ST segment and the electrical conduction system of the heart. Enhance your understanding of cardiac health with this informative quiz.