Cardiovascular and Pulmonary: Interpretation of ECG's

Question 1

Calculate Heart Rate: Large boxes

Answer 1

• Count the number of QRS complex peaks in a 6 second strip and multiply by 10.
• Each large box, outlined by a dark line=0.2 seconds therefore you need 30 large boxes to=6 seconds
• If heart rate is irregular use the longest strip possible up to one minute.

Question 2

Calculate Heart Rate: Small boxes

Answer 2

• Count the number of small boxes between two adjacent QRS complex peaks and divide by 1500.
• Each small box=0.04 seconds.

Question 3

Arrhythmias: Ventricular

Answer 3

• Conduction in the ventricles outside the normal conduction system
• Significant in adversely affecting cardiac output

Question 4

Arrhythmias: Ventricular: Premature Ventricular Contraction

Answer 4

• Premature beat arising from the ventricle

- Sometimes occurs occasionally in the majority of the population

Question 5

Arrhythmias: Ventricular: Premature Ventricular Contraction: Presentation on ECG’s

Answer 5

• No p wave
• Premature and wide QRS
• Long compensatory pause

Question 6

Arrhythmias: Ventricular: Premature Ventricular Contraction:

Answer 6

• Serious of greater than 6 PVC’s per minute

Question 7

Arrhythmias: Ventricular: Premature Ventricular Contraction: R on T phenomenon

Answer 7

• Very early PVC

- Sharp drop in conduction just before and continuous with T wave

Question 8

Arrhythmias: Ventricular: Ventricular Tachycardia (V-tach)

Answer 8

• Four or more PVC’s occurring sequentially

- Very rapid rate 150-200bpm

Question 9

Arrhythmias: Ventricular: Ventricular Tachycardia: Non-sustained V-Tach

Answer 9

• Four or more PVC’s terminating spontaneously in less than 30 seconds

Question 10

Arrhythmias: Ventricular: Ventricular Tachycardia: Sustained V-Tach

Answer 10

• Four or more PVC’s for duration greater than 30 seconds.

- May require termination due to hemodynamic response

Question 11

Arrhythmias: Ventricular: Ventricular Fibrillation (V-fib)

Answer 11

• Chaotic electrical activity in the ventricle originating from multiple places outside the normal conduction pathway.
• Is an emergency and will require a medical treatment with CPR and defibrillation

Question 12

Arrhythmias: Ventricular: Ventricular Fibrillation: Presentation on ECG’s

Answer 12

• No QRS complexes

- No effective cardiac output

Question 13

Arrhythmias: Atrial

Answer 13

• Electrical signaling from outside the sinus node in the atria

Question 14

Arrhythmias: Atrial: General presentation on ECG’s

Answer 14

• P waves will be abnormal

Question 15

Arrhythmias: Atrial: Atrial fibrillation

Answer 15

• Non-identifiable p-waves
• P waves will be close to flat lined with QRS complexes
• P waves will be difficult to identify from QRS complexes
• Greater than 300bpm HR

Question 16

Arrhythmias: Atrial: Atrial Tachycardia

Answer 16

• Several heart beats in a short period of time initiated at the atria, indicated by a p wave, followed by several QRS complexes over a few seconds.
• P waves during rapid QRS complex portion of ECG will be difficulty to define from T waves of previous QRS complex and initiation of following QRS complex
• 140-250bpm

Question 17

Arrhythmias: Atrial: Atrial Flutter

Answer 17

• Several P waves in a sawtooth pattern between QRS complexes
• 250-350bpm

Question 18

Arrhythmias: Atrioventricular Blocks

Answer 18

• Abnormal delays or lack of conduction in conduction system.
• Conduction from the atria to the ventricles is blocked or delayed.

Question 19

Arrhythmias: Atrioventricular Blocks: First Degree

Answer 19

• Condition of abnormally slow conduction through the AV node.
• Defined by ECG changes that include a PR interval of greater than 0.20 without disruption of atrial to ventricular conduction.

Question 20

Arrhythmias: Atrioventricular Blocks: Second Degree

Answer 20

• Conduction of atrial impulse through the AV node and/or His bundle is delayed or blocked

Question 21

Arrhythmias: Atrioventricular Blocks: Second Degree: Mobitz Type I

Answer 21

• Conduction is slowed usually due to high vagal tone not typically associated with structural heart disease.
• Gradual prolongation of PR interval until block occurs

Question 22

Arrhythmias: Atrioventricular Blocks: Second Degree: Mobitz Type II

Answer 22

• Conduction is slowed often associated with structural heart disease
• Constant PR interval before a block occurs
• Can progress to a Third degree AV block

Question 23

Arrhythmias: Atrioventricular Blocks: Third Degree

Answer 23

• Complete block
• Can be life threatening
• Requires medication, pacemaker or surgery

Question 24

Arrhythmias: Atrioventricular Blocks: Third Degree: Presentation in ECG

Answer 24

• No conduction through the AV node
• Complete dissociation between the atria and the ventricles
• Random dissociated P waves and QRS complexes on an ECG

Question 25

Arrhythmias: ST segment Changes: Impaired coronary perfusion

Answer 25

• Lowered ST segment

Question 26

Arrhythmias: ST segment Changes

Answer 26

• ST changes of greater than 1mm on 2 consequeitve leads is considered abnormal EXCEPT in leads V2 and V3

Question 27

Arrhythmias: ST segment Changes: Gender and Age

Answer 27

• ST elevation of greater than or equal to 2mm in men over 40
• ST segment elevation of greater than 2.5mm in Men under 40
• ST segment elevation of greater than 1.5mm in women