The Heart - Arrhythmias

Deoxygenated Blood Goes into heart via

Vena Cava

Deoxygenated BLood pumped from heart to lungs via

Pulmonary Artery

Oxygenated Blood goes into heart from Lungs via

Pulmonary Vein

Oxygenated Blood pumped round body via

Aorta

Normal resting heart rate is between ? & ? bpm

60 and 100bpm

athletes resting heart rate of ? to ? bpm, or lower.

40 to 60

normal heart rhythm is ___rhythm; rate will vary between patients, but pulse should be_____

SINUS - REGULAR

electrical signals generated in ______ node of right atrium

sinoatrial (SA) node - hearts pacemaker

Arrhythmias occur in which 2 places ?

Supraventricular- above the ventricles

Ventricular - within ventricles

Arrhythmias that slow down HR ____cardia to less than 60 bpm or speed up _____cardia to more than 100 bpm

Bradycardia- less than 60bpm

Tachycardia - more than 100bpm

What are the Symptoms of arrhythmias ?

palpitations,dizziness/light headed,faint, SOB,chest pain, fatigue, pounding sensation in neck,loss of consciousness, cardiac arrest or no symptoms

How to diagnose arrhythmias ?

Pulse, Listen to heart sounds, ECG pattern.

2 Types of Bradycardia arrhythmias?

Sinus Bradycardia - slow but normal rhythm

Heart Block - most common is atrioventricular AV block

Cause of AV Block

Myocardial Infarction, CHD, infection, beta-blockers, digoxin, verapamil

What are the 4 types of Tachycardias ?

Sinus (normal or drug) or Ventricular (inc torsades de pointes)

Atrial Fibrillation or Ventricular Fibrillation

Fast HR but normal rhythm/ exercise /infection, hypotension, hyperthyroidism, ananaemia,nicotine, salbutamol, levothyroxine, theophylline

Sinus Tachycardia

Extra ventricular beat 'ectopics'. Acute MI, ischaemic heart disease (narrow fatty deposits), myocarditis (inflammation of the heart tissue), diseases of heart valves

Ventricular tachycardia

Ischemia

reduced blood flow

Name the type of Ventricular tachycardia which is due to QT prolongation

Torsade de pointes

Electrical signal wrong place/ atria quivers/ fibrillates rapidly (300-600 bpm). Disorganised rhythm transmitted to ventricles → HR 100-180 bpm.

Atrial Fibrillation AF

Rapid fibrillation of ventricles - cardiac output down- lose consciousness in 20/30 secs - common cause death - acute MI.

Ventricular Fibrillation

Non-drug management of arrhythmias?

pacemaker / defibrillation / cardioversion / ablation

most common supraventricular tachycardia, affecting about 1 in 20 of people over 65yrs in UK ?

Atrial Fibrillation AF

AF increases the risk of a person developing what ?

A Stroke, Heart Failure, Angina and Thromboembolism (blood clots)

What heart related conditions cause AF?

Structural Heart Probs -Hypertension - Ischaemic Heart Disease (blood vessels supplying the heart are narrowed or blocked) -Coronary Vascular Disease

non heart related conditions that cause AF?

COPD, Diabetes, Alcohol, Thyrotoxicois

What are the 3 ways to Manage AF ?

Stroke prevention, Rate control, Rhythm control

Stroke prevention

With anticoagulants DOACs or Vit K blocker.

Rate control

With beta-Blockers, CCB (verapamil, diltiazem) or Digoxin

Rhythm control

With Electrical cardioversion, standard beta-blockers or Amiodarone

Management of AF - Stroke Prevention - Before start anticoagulant do stroke risk v bleed risk with 2 assessments

CHA₂DS₂-VASc Stroke risk Score and ORBIT Bleeding risk score

first line anticoagulants for Stroke prevention in management of AF ?

DOACs - apixaban, dabigatran, edoxaban, and rivaroxaban

‘Vitamin K blocker’ that lowers the risk of clotting that cause DVTs

Warfarin

3 Types of anticoagulants?

Vitamin K antagonists, DOACs and Parenteral anticoagulants

what drugs dissolve already formed blood clots?

fibrinolytics (or thrombolytics)

What is the antidote to Warfarin ?

Phytomenadione (Vitamin K)

How long before surgery (including dental) should you stop Warfarin?

5 days

INR

international normalised ratio

What does INR test?

how long it takes blood to clot compared to someone not taking anticoagulants.

 For someone not taking anticoagulants, the INR should be around ?

1

Target INR of 2.5 (2.5 times longer to clot than someone with an INR of 1) is used for treatment of ?

DVT , PE, AF

Warfarin takes a few days to reach therapeutic range - pts given what in hospital in meantime?

Low molecular weight heparin while warfarin is loading.

DOACs

apixaban, dabigatran, edoxaban, and rivaroxaban

All of the DOACs can cause what?

Anaemia; haemorrhage; nausea/vomiting

Apixaban adverse reaction

Skin reactions

Dabigatran adverse reaction

Abnormal liver function.

Rivaroxaban adverse reaction

Constipation; diarrhoea; dizziness; headache; hypotension; skin reactions

Edoxaban adverse reaction

Dizziness; headache; skin reactions

DOACs are used for what?

prevention of stroke and management of AF

Prevention and management of DVT and PE

after elective hip or knee replacement surgery which doac is NOT used?

edoxaban

parenteral anticoagulants used in management of AF for stroke prevention?

unfractionated heparin, low molecular weight heparin , fondaparinux.

Unfractionated heparin begins anticoagulation rapidly does it have long or short duration of action?

short 4-6 hours

How is unfractionated heparin given?

by injection: either subcutaneously or as an intravenous infusion. 

Low Molecular Weight Heparin (LMWH) examples please?

Dalteparin, Enoxaparin, Tinzaparin.

How is LMWH administered?

subcutaneously and usually doses are calculated according to patient’s bodyweight.

What is a side effect of unfractionated heparin when low platelet count ?

heparin induced thrombocytopenia (HIT)

Advantages of LMWH over unfractionated heparin?

lower risk of HIT

longer duration of action

easier to administer in PFS

can be administered at home

When is Fondaparinux used?

for prevention of DVT in surgical or immobilised patients

for treatment of DVT or PE.

In patients who have unstable angina or who have had an MI.

If a pt develops HIT while using an anticoagulant then the drug must be stopped and what alternative anticoagulants must be used ?

danaparoid and argatroban - direct thrombin inhibitors

Warfarin - True or False - Topical preparations can potentially have an impact of INR levels

True

Warfarin - True or False - Patients must not have any injections while taking warfarin?

False - Patients with a stable INR and regular testing will be able to have vaccinations in the same way as anyone else

Warfarin - True or False - INR monitoring is required every 6 months?

False - Once stable, INR blood tests every 8-12 weeks.

Warfarin - True or False - Patients should avoid all leafy green vegetables?

False - warfarin dose will be altered to meet the INR they need alongside eating regular leafy greens.

Management of AF - Rate Control - which drugs reduce the patient's heart rate but without affecting the heart rhythm?

Standard β-blockers, e.g. metoprolol, bisoprolol, CCBs diltiazem & verapamil, and Digoxin

Rate Control - Can AF patients take Beta-blocker & Digoxin or CCB & Beta Blocker ?

Yes - AF, patients may take a combination of 2 from the different groups.

Adverse effects of beta-blockers?

Bradycardia, Bronchospasm,Tiredness

Is Bronchospasm an adverse effects of beta-blockers?

yes

Is Constipation an adverse effects of beta-blockers?

NO

are Warm hands & feet an adverse effects of beta-blockers?

No

Is Dry skin an adverse effects of beta-blockers?

No

Is Tiredness an adverse effects of beta-blockers?

Yes

Calcium channel blockers used for Rate control in AF?

verapamil and (diltiazem not licensed)

Side effects of CCB verapamil ?

hypotension, constipation, hepatic impairment (dark urine, pale stools, yellowing skin or whites of eyes)

Rate Control drug with narrow thera index & long half-life, used on sedentary pts as, doesn't control HR during exercise

digoxin

mode of action of digoxin

SLOWS electrical conduction in the AV node., INCREASES force of contractions in the heart

Rate control AF - side effects of Digoxin

confusion, nausea, anorexia,vision disturbance

How do you manage AF - Rhythm control ?

with Electrical cardioversion, standard beta-blockers or Amiodarone

Management AF - Rhythm control - Which drugs ?

Amiodarone, Dronaderone, Metoprolol

Management AF - Rhythm control - non-drug methods?

Electrical cardioversion -DCCV: Direct current cardioversion

electric shock across chest wall

always started in hospital.reduces electrical activity in heart, long half life, loading dose, serious side effects which limit it's use

Amiodarone

AF that terminates spontaneously?

Paroxysmal AF

Treatment options for Paroxysmal AF

Stop alcohol/caffeine, “Pill-in-the-pocket” (eg flecainide) , rate/rhythm control drugs, Anticoagulants as risk of thromboembolism

“Pill-in-the-pocket” for paroxysmial AF

Flecainide