Heart block

Question 1

what is heart block

Answer 1

When electrical signal is delayed or stopped during conduction

Question 2

Different types of heart block

Answer 2

1st- delayed electrical impulse 
PR >200 ms 
2nd 
type 1- mobitz 1 or wenckeback
type 2- mobitz 2
3rd type: electrical impulse is interrupted

Question 3

difference between heart block type 2

Answer 3

Mobitz 1 - PR interval becomes longer and longer until it does not reach the ventricles- dropped beat- every 6th P wave
This causes the ventricles to contract- escape beat
P-P distance remains constant

Mobitz type 2- PR wave does not become progressively longer

Question 4

Treatment

Answer 4

• Medication to increase HR
• Permanent pacing: implant detects delay and then sends impulse to contract
• Temporary pacing

Question 5

Causes

Answer 5

1-idiopathic:
-in the elderly
-in the young: genetic
2-myocarditis- inflammation of the cardiac muscle wall
3- cardiomyopathies: diseases of the heart wall
4- Ischaemic heart disease

Question 6

indications for temporary pacing

Answer 6

• through electrolytes on the skin
• Prophylactic; when patient at high risk of developing bradycardia e.g. type2/3 block
• When patient presents with intermittent bradycardia associated with syncope

Question 7

Indications for permanent pacing

Answer 7

• through pacemaker after or in preparation for ablation
• patient presents with LBBB/RBBB
• patient presents with carotid hypersensitivity
• patient presents with sinus node disease
• patient presents with symptomatic 2/3rd degree heart block
• patient presents with AV block associated with neuromuscular disease

Question 8

ECG for heart block

Answer 8

type 1 : PR segment>200ms
type 2 a: PR interval increasing- every 6 waves a QRS complex is dropper- escape beat
type 2 b: PR interval stays the same- random QRS complexes dropped
type 3: P wave is not followed by a QRS complex