Arrhythmia and Endocarditis

Question 1

What is sinus rhythm?

Answer 1

P wave that precedes each QRS complex

Question 2

What are the main consequences of arrhythmia?

Answer 2

Sudden death, syncope, dizziness, palpitations

Question 3

What are the 2 main categories of tachycardia?

Answer 3

1) Ventricular Tachycardia

2) Supra-ventricular tachycardia

Question 4

Where do supra-ventricular tachycardia’s arise from and what sort of QRS complexes?

Answer 4

Arise: Atria/Atrio-ventricular junction

- Narrow QRS complexes

Question 5

Where do ventricular tachycardia’s arise from and what sort of complexes?

Answer 5

Arise: Ventricles

- Broad QRS complexes

Question 6

What are 5 S-VT’s?

Answer 6

1) Atrial Fibrillation 2) Atrial Flutter 3) AV node re-entry Tachycardia 4) Accessory pathway 5) Focal atrial tachycardia

Question 7

What are 4 main causes of sinus tachycardia?

Answer 7

1) Physiological exercise response 2) Fever 3) Anaemia 4) Heart Failure 5) Hypovolemia

Question 8

What are the main symptoms of AF?

Answer 8

1) Palpitations 2) Shortness of breath 3) Fatigue 4) Chest pain 5) Increased T-E risk and stroke

Question 9

Why will AF ECG show absent P wave and fine baseline oscillation?

Answer 9

Atria fire lots, so chaotic as AV node and ventricles won’t keep up –> Irregularly irregular pulse

Question 10

What is main treatment for AF?

Answer 10

1) Rate control (BB, CCB and digoxin)
2) Rhythm Control (Electrical/Pharmacological cardioversion)
3) Long Term: Catheter ablation/pacemaker
4) Flecainide

Question 11

What will Atrial Flutter ECG show?

Answer 11

1) Narrow QRS complex 2) “Sawtooth” flutter waves

Question 12

What pathophysiological mechanism will atrial flutter show?

Answer 12

Re-Entry mechanism: Blockage of normal circuit, another pathway forms, takes different course and re-enters circuit –> Tachycardia

Question 13

What is the most common S-VT and what will be seen on ECG and S/S?

Answer 13

-AV node re-entry Tachycardia (AVNRT)
- P waves within the ECG)
S/S: Sudden onset/offset palpitations, neck pulsation, chest pain and shortness of breath

Question 14

What are the two main treatment methods for AVNRT?

Answer 14

Acute: Vagal manoeuvre/ Adenosine
Drugs: BB, CCB, Flecainide

Question 15

What is the PP of accessory pathway arrhythmia?

Answer 15

Congenital muscle strands end up connecting Atria and Ventricle (Pre-Excitation of Ventricles)

Question 16

What are the S/S of APA?

Answer 16

1) Delta wave 2) Short PR interval 3) Slurred QRS complex

Wolff-Parkinson-White syndrome

Question 17

What is the PP of focal atrial tachycardia?

Answer 17

Another Atrium becomes more autonomic than sinus node, so sinus node function taken over –> Focal atria tachycardia
(Abnormal P wave before normal QRS)

Question 18

What are ectopic beats?

Answer 18

Benign arrhythmias caused by premature discharge (Skipped beat symptoms)

Question 19

What are S/S of long QT syndrome?

Answer 19

Si: Palpitations and Syncope
Symp: Congenital, Variety of drugs, Electrolyte disturbances

Question 20

What are the main causes of sinus bradycardia?

Answer 20

1) Ischaemia 2) Fibrosis of atrium 3) Inflammation 4) Drugs

Question 21

What criteria is sued to help diagnose infective endocarditis?

Answer 21

Duke Criteria:

1) Positive Blood Culture w/ typical IE microbes
2) Positive echo showing endocardial involvement

Question 22

What is infective endocarditis?

Answer 22

Infection of the heart valves/ Endocardial lined structure within the heart

Question 23

What are the 4 types of IE? And which is more likely to systemically spread?

Answer 23

1) LS native 2) LS prosthetic 3) RS native 4) Device related

Left sided IE: Thrombo-emboli (RS to lungs)

Question 24

What are the main IE risk factors and which bacteria most likely to cause it?

Answer 24

RF: Regurgitant/Prosthetic Valve, Infectious material introduced into blood stream/during surgery
Bac: Staph aureus. staph epidermidis, strep viridians

Question 25

What's the PG, people at risk and hallmark?

Answer 25

PG: Microbial infection -> Valve vegetation -> Cardiac Valve distortion -> Cardiac failure and septic problems Risk: Elderly, IVDU, Rheumatic fever and Prosthetic valves Hallmark: Vegetation on valves (Fibrin lumps)

Question 26

Where will vegetation most likely be seen, and what are the S/S of IE?

Answer 26

Vegetation: Atrial surface of AV valves, Ventricular surface of SL valves Sy: Systemic infection, embolisation and valve dysfunction Si: Heart murmurs, roth spots, janeway lesions, osler's nodes and splinter haemorrhages

Question 27

What are the main treatment methods?

Answer 27

1) Antibiotics based on cultures 2) Treat complications 3) Surgery (AB not working, complications, remove infected devices and replace valve, remove large vegetations)

Question 28

Why is it important to remove large vegetations?

Answer 28

Prevent them embolising and causing a stroke

Question 29

What investigations would be done for IE?

Answer 29

1) Blood cultures for diagnosis (-ve if recently had AB) 2) Echo shows endocardial involvement (TTE/TOE) 3) Bloods --> Raised ESR/CRP 4) ECG

Question 30

What are the advs/disadvs of TOE and TTE?

Answer 30

TTE: Safe, non-invasive but poor images TOE: Excellent images, discomfort and small risk of perforation/aspiration