Lecture 4.2: ECG Hypertrophy of Atria and Ventricles

Question 1

What are 4 best leads to see atrial enlargement?

Answer 1

I, II, III, and V1

Question 2

What is the p-wave like in RAE and is taller in which lead?

Answer 2

Tall, pointed; taller in III than in I

Question 3

What is the p-wave like in LAE and is taller in which lead?

Answer 3

Wide, notched (“M” shape); taller in I than in III

Question 4

RAE is associated with what 2 etiologies?

Answer 4

• Tricuspid valvular disease
• Pulmonary HTN

Question 5

In RAE the tall peaked P waves will have amplitude greater than ______mm in leads II, III, and aVF

Answer 5

>2.5 mm

Question 6

What are 2 etiologies causing LAE?

Answer 6

Mitral stenosis and Mitral regurgitation

Question 7

In LAE the second half of the P wave will be negative in which leads?

Answer 7

V1 or III

Question 8

Interpret this EKG

Answer 8

LAE with 1st degree AV block

Question 9

What is the most common cause of LVH?

Other causes?

Answer 9

• HTN = most common
• Also, AS, AI, hypertrophic cardiomyopathy and coarcatation of aorta

Question 10

How does hypertrophy of the LV affect the electrical transmission as it passes through it and arrives at epicardial surface?

Effect on the QRS complex?

Answer 10

• Impulse will take longer = voltage and interval of QRS will increase
• Taller R waves over LV + deeper S waves over RV

Question 11

Which feature of the ventricle is the main determinant of QRS voltage?

Answer 11

Total muscle mass

Question 12

Criteria for LVH lack _______ (specificity/sensitivity), but are ______(sensitive/specific)

Answer 12

Criteria for LVH lack sensitivity, but are specific

Question 13

Using the Romhilt-Estes Scoring System for LVH how many points is considered probably LVH and how many for dx of LVH?

Answer 13

• Probably LVH = 4
• LVH = 5

Question 14

Using the Romhilt-Estes Scoring System for LVH, what size R or S in the limb leads, V1-V3, and V5-V6 is considered 3 points?

Answer 14

• R or S in limb lead = 20 mm or more
• S in V1-V3 = 25 mm or more
• R in V5-V6 = 30 mm or more

Question 15

Using the Romhilt-Estes Scoring System for LVH, what type of axis deviation is worth 2 points?

Answer 15

LAD -30° or more

Question 16

Using the Romhilt-Estes Scoring System for LVH, a QRS interval of how long is worth 1 point?

Answer 16

≥ .09 sec

Question 17

Using the Romhilt-Estes Scoring System for LVH what ST finding is worth 3 points and which is worth 1 point?

Answer 17

• Any ST shift (WITHOUT digitalis) = 3 points
• Typical “strain” ST-T (WITH digitalis) = 1 point

Question 18

Interpret this EKG

Answer 18

Left ventricular hypertrophy

Question 19

Interpret this EKG; what do the arrows show?

Answer 19

LVH; arrows showing ST strain

Question 20

List 4 etiologies responsible for RVH?

Answer 20

• COPD
• RVOT obstruction, VSD
• Congenital = TOF, pulmonic stnosis, and transposition of great vessels
• Valvular = Mitral stenosis, tricuspid regurgitation

Question 21

What kind of axis deviation is a clue for RVH?

Answer 21

RAD +90° or MORE

Question 22

Which leads with an R/S and S/R ratio >1 or more, is suggestive of RVH?

Answer 22

• R/S ratio >1 in V1
• S/R ratio >1 in V6

Question 23

How big of an R in V1 is suggestive of RVH?

Answer 23

7 mm or more

Question 24

How big of an R in V1 + S in V6 is suggestive of RVH?

Answer 24

10 mm or more

Question 25

What are 6 causes of dominant R waves in V1?

Answer 25

• RVH
• Posterior or lateral MI
• WPW
• Hypertrophic cardiomyopathy
• Muscular dystrophy
• Normal variant

Question 26

Interpret this ECG; rate, rhytm, axis

Answer 26

65 beats/min; RAD; RVH