Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Cardiology Secrets > ELECTROCARDIOGRAPHY > Flashcards

ELECTROCARDIOGRAPHY Flashcards

1
Q

What are the most commonly used voltage criteria to diagnose left ventricular hypertrophy?

A

• R wave in V5-V6 plus S wave in V1-V2 > 35 mm (Sokolow criterion)
• R wave in lead I plus S wave in lead III > 25 mm
• R wave in lead aVL plus S wave in V3 > 28 mm in men and > 20 mm in women (Cornell criteria)

These criteria are used in electrocardiographic (ECG) diagnosis of left ventricular hypertrophy (LVH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are common nonvoltage ECG findings that suggest LVH?

A

• Left atrial enlargement
• Widened QRS complex > 90 milliseconds
• Repolarization abnormality (ST-segment and T-wave abnormalities)
• Left axis deviation
• R-wave peak time > 50 milliseconds

These findings are indicative of left ventricular hypertrophy on an ECG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the most commonly used criteria to diagnose right ventricular hypertrophy?

A

• R wave in V1 ≥ 7 mm
• R/S wave ratio in V1 > 1

These criteria assist in diagnosing right ventricular hypertrophy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What criteria are used to diagnose left atrial enlargement?

A

• P-wave total width > 0.12 seconds in inferior leads (II, III, aVF) with a double-peaked P wave
• Terminal portion of the P wave in lead V1 ≥ 0.04 seconds wide and ≥ 1 mm deep

These measurements help identify left atrial enlargement on an ECG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What ECG finding suggests right atrial enlargement?

A

P-wave height in the inferior lead ≥ 2.5 mm

This finding is indicative of right atrial enlargement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the normal rate of a junctional rhythm?

A

40 to 60 beats per minute (bpm)

Junctional rhythms can also be categorized as accelerated (61 to 99 bpm) or junctional tachycardia (> 100 bpm)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How can one distinguish a junctional escape rhythm from a ventricular escape rhythm in a patient with complete heart block?

A

• Junctional escape rhythms occur at a rate of 40 to 60 bpm and are usually narrow complex
• Ventricular escape rhythms occur at a rate of 30 to 40 bpm and are typically wide complex

This distinction is important in diagnosing heart block

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the three types of heart blocks.

A

• First-degree heart block: PR interval is a fixed duration > 0.20 seconds
• Second-degree heart block: Mobitz type I (Wenckebach) - PR interval increases until a P wave is not conducted; Mobitz type II - fixed PR interval with occasional nonconducted P waves
• Third-degree heart block: All P waves are not conducted; atrial rate is faster than ventricular escape rate

Each type of heart block has distinct features critical for diagnosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the causes of ST-segment elevation?

A

• Acute myocardial infarction (MI)
• Prinzmetal angina
• Cocaine-induced MI
• Takotsubo cardiomyopathy
• Brugada syndrome
• Pericarditis
• Left ventricular aneurysm
• Left bundle branch block (LBBB)
• LVH with repolarization abnormalities

These causes must be considered in patients presenting with ST-segment elevation on an ECG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the ECG findings of hyperkalemia?

A

• Peaked T waves
• Loss of P waves
• QRS widening
• ST-segment elevation
• Preterminal finding: sinusoidal pattern

These changes reflect the effects of elevated potassium levels on cardiac repolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the ECG findings in pericarditis?

A

• PR segment depression
• Diffuse ST-segment elevation
• ST depression in lead aVR
• Later T wave inversions

These findings are characteristic of pericarditis on an ECG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is electrical alternans?

A

Alteration of the amplitude of the QRS complex in the presence of large pericardial effusions

This finding indicates significant pericardial effusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the main ECG findings in hyper- and hypocalcemia?

A

• Hypercalcemia: QT interval shortens
• Hypocalcemia: QT interval prolongs due to delayed repolarization

These changes are important for understanding the effects of calcium levels on cardiac function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What ECG findings may be present with a pulmonary embolus?

A

• Sinus tachycardia
• Right atrial enlargement (P pulmonale)
• T-wave inversions in leads V1-V2

These findings can raise suspicion of pulmonary embolism in patients with chest pain or shortness of breath

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is the QT interval calculated?

A

Measured from the beginning of the QRS complex to the end of the T wave

The corrected QT interval (QTc) accounts for heart rate variations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is torsades de pointes?

A

A ventricular arrhythmia that occurs in the setting of QT prolongation, characterized by twisting QRS axis around the isoelectric line

It is typically unstable and may require prompt defibrillation

17
Q

What are cerebral T waves?

A

Strikingly deep and inverted T waves seen with central nervous system diseases, particularly hemorrhages

They are due to prolonged repolarization and should not be confused with cardiac ischemia

18
Q

What are Osborne waves?

A

Upward deflections at the J point of the QRS complex occurring in hypothermia

These waves indicate repolarization abnormalities due to low body temperature

19
Q

What findings help distinguish ventricular tachycardia from supraventricular tachycardia with aberrancy?

A

• Concordance in precordial leads
• Initiation of R wave to peak of S-wave duration > 100 milliseconds
• AV dissociation

These criteria aid in differentiating between VT and SVT

20
Q

What are the ECG criteria for left bundle branch block?

A

• QRS > 120 milliseconds
• Broad R waves in I, V5, V6 with no Q waves
• Broad monomorphic S waves in V1
• ST and T waves opposite in direction to QRS

These criteria are essential for diagnosing left bundle branch block

21
Q

What are the ECG criteria for right bundle branch block?

A

• QRS > 120 milliseconds
• RSR’ (M-shaped QRS complex) in V1 and V2
• Broad S wave in lateral leads (V5, V6, I, aVL)

These criteria are crucial for diagnosing right bundle branch block

22
Q

What ECG finding is associated with central nervous system disease, particularly subarachnoid and intracerebral hemorrhages?

A

Markedly deep and inverted T waves

This finding is significant in diagnosing central nervous system conditions.

23
Q

What are Osborne waves associated with?

A

Hypothermia

Osborne waves are characteristic ECG findings in cases of severe hypothermia.

24
Q

What does the Sgarbossa criteria help clinicians identify in patients with left bundle branch block?

A

ST-segment–elevation myocardial infarction (STEMI)

These criteria are essential for accurately diagnosing STEMI despite the presence of LBBB.

25
Q

List the three components of the Sgarbossa criteria.

A
  • Concordant ST-segment elevations >1 mm in leads with a positive QRS complex
  • Concordant ST-segment depressions >1 mm in leads with a negative QRS complex (usually V1-V3)
  • Discordant ST-segment elevations >0.5 mm
26
Q

What is Wellens’ sign an ECG manifestation of?

A

Proximal left anterior descending stenosis in patients with acute coronary syndrome

Wellens’ sign is a critical indicator in the assessment of coronary artery disease.

27
Q

Describe the characteristics of Wellens’ sign on ECG.

A

Deep (>2 mm), symmetric, and often biphasic T-wave inversions in the anterior precordial leads

This specific pattern is indicative of significant coronary artery stenosis.

28
Q

What does concordance in an ECG refer to?

A

Both the QRS complex and the ST segment have a positive or a negative axis.

29
Q

What does discordance in an ECG indicate?

A

The axis of the QRS differs from that of the ST segment.

30
Q

What ECG findings help determine if there is an ST-segment–elevation myocardial infarction in the presence of left bundle branch block?

A

Look for concordant and discordant ST-segment changes

These findings are crucial for accurate diagnosis despite the masking effects of LBBB.

31
Q

True or False: Left bundle branch block (LBBB) inherently has ST abnormalities.

A

True

32
Q

In the context of ECG, what is the significance of deep T-wave inversions?

A

They are often seen in conditions like Wellens’ sign and indicate severe coronary artery disease.

Cardiology Secrets (26 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions