Cardiovascular Flashcards
What bacteria is responsible for rheumatic valve disease?
Streptococcus pyogenes
What are the three leaflets of the aortic valve called?
Right
Left
Non-coronary
What are three causes of aortic stenosis?
Age (wear and tear –> calcification)
Rheumatic valve disease
Congenital
Describe the murmur associated with aortic stenosis
Ejection systolic murmur
Radiates to the right upper sternal edge, suprasternal notch and carotids
What is the progressive effects of aortic stenosis?
Increased LV cavity pressure –> pressure overload –> LV hypertrophy
What are the symptoms of aortic stenosis?
SOB Chest pain Pre-syncope Syncope Reduced exercise capacity
What are the causes of aortic regurgitation?
Degenerative Rheumatic valve disease Aortic root dilation Systemic disease Endocarditis
Give examples of systemic diseases that can result in aortic regurgitation
Marfan’s syndrome
Ehler Danlos syndrome
Ankylosing spondylitis
SLE
What is the effect of aortic regurgitation?
Blood pushed into aorta In diastole, the valves are incompetent Blood flows back into LV Volume overloaded LV dilation
What are the symptoms of aortic regurgitation?
SOB
Reduced exercise capacity
What is the prevalence of people having a bicuspid aortic valve rather than a tricuspid aortic valve?
1-2%
What are people with a bicuspid aortic valve prone to developing?
Premature dysfunction
Describe the mitral valve
Fibrous annulus - this can become dilated which pulls the valve leaflets apart
Anterior and posterior leaflets - anterior do the most work
Chordae tendinae and papillary muscles
What is the nomenclature of the anterior and posterior leaflets of the mitral valve?
A1, A2, A3
P1, P2, P3
What is the major cause of mitral stenosis?
Rheumatic valve disease
What is the effect of mitral stenosis?
Pressure overload
Dilated LA
AF
Other than AF, what are the two other potential effects of mitral stenosis?
Pulmonary hypertension
Secondary right heart dilatation
What are the symptoms of mitral stenosis?
SOB Palpitations Chest pain Haemoptysis Right heart failure symptoms (pitted oedema, ascites etc)
What is the effect of mitral regurgitation?
Volume overload in both LA and LV
LA and LV dilation
Pulmonary hypertension and secondary right heart dilation
AF
What are the symptoms of mitral regurgitation?
SOB
Palpitations
RHF symptoms
Who is most likely to develop pathology of the pulmonary valve?
Children and young adults
What are the causes of tricuspid valve pathologies?
Pulmonary hypertension
IVDU
Endocarditis
How should valvular disease be assessed?
History Examination - murmur BP ECG ECHO - valvular dysfunction CT MRI Exercise tolerance test, CPET, Stress ECHO
What medical treatments can be used in the management of valvular disease?
Diuretics - reduce overload on heart
Mainly surveillance - watch and wait
What are the different surgical options for the management of valvular disease?
Valve repair
Valve replacement
Mechanical
Tissue
What type of valve replacement requires warfarin?
Mechanical
What are the two procedures that can be used in the management of valvular disease?
TAVI (transcatheter aortic valve intervention)
Valvuloplasty
When can valvuloplasty be used?
Role in mitral valve disease
Mainly young people with RVD
Buy time before valve replacement
What is the risk of stroke associated with AF?
5-fold increase compared to general population
What percentage of the population have AF?
1.5-2% (prevalence is increasing with the ageing population)
Give examples of conditions that predispose to or encourage the progression of AF
HTN Symptomatic HF Valvular heart disease Cardiomyopathies ASDs Coronary artery disease Thyroid dysfunction Obesity DM COPD Sleep apnoea Chronic renal disease
What symptoms are associated with AF?
Asymptomatic
Palpitation
Dyspnoea
(rare: chest pain, syncope)
May present with the complications of AF (stroke/peripheral emboli)
What type of pulse is associated with AF?
Irregularly irregular
What are the three types of AF?
Paroxysmal
Persistent
Permanent
Describe paroxysmal AF
Intermittent
Starts and stops
Can last from 30s to over 24hrs at a time
Describe persistent AF
Requires intervention to terminate the arrhythmia (IV antiarrhythmic drug or DC cardioversion)
Describe permanent AF
Continually there, won’t try to restore sinus rhythm
What ECG changes are associated with AF?
Absence of P waves
Irregular QRS complex
Describe the ECG changes associated with AF
Atria aren’t contracting as a synctium
Different cells are contracting at different rates
There are multiple entry circuits
Ventricles have a variable rate dependent upon which impulses are able to pass through the AV node –> Bundle of His –> activate the ventricles
Describe atrial flutter
Re-entry around the tricuspid valve
Atria contracting at a rate of 250-300bpm
Saw-tooth pattern on ECG
On what ECG leads can a saw-tooth pattern be seen during atrial flutter?
Inferior leads II, III and aVF
What are the haemodynamic effects of AF and atrial flutter?
Loss of cardiac output
Atria are not beating in a coordinated fashion so blood clots may form in the atria –> break off –> thrombus can emboli to the brain, kidneys etc
What are the treatment aims in AF?
Prevention of stroke Symptom relief Optimum management of concomitant cardiovascular disease Rate control \+/- correction of rhythm disturbance
What are the essential investigations for a patient with AF?
ECG - confirm arrhythmia
ECHO - structural heart disease
Thyroid function tests
LFTs
What is the target HR for a patient with AF who is:
a) asymptomatic
b) symptomatic
Asymptomatic: <110 bpm
Symptomatic: <80 bpm
If a patient doesn’t have cardiac failure, how should their AF be managed?
Beta blocker (bisoprolol 2-5-5mg OD or atenolol 25-50mg BD) OR Ca antagonist (verapamil 120-240mg BD)
What is the second line treatment for a patient with AF who does not have HF?
Digoxin
What scoring system can be used to ascertain a patient’s risk of having a stroke?
CHA2DS2-VASc
out of 9
What are the components of the CHA2DS2-VASc scoring system?
Congestive heart failure/LV dysfunction HTN Age >/= 75 (2pts) DM Stroke/TIA/thrombo-emobolism (2pts) Valvular disease Age 65-74 Female sex
What should the INR target be for a patient with AF?
2-3
What is the risk of an INR >3?
Increased risk of intracranial bleed
What is the risk of an INR <2?
Increased risk of stroke
What treatment for AF requires INR measurements?
Warfarin
What are the new oral anti-coagulants that can be used in the management of AF?
Dabigatran - thrombin inhibitor
Rivaroxaban - factor Xa inhibitor
Apixaban - factor Xa inhibitor
Edoxaban - factor Xa inhibitor
Who should be referred for specialist assessment?
Patients who are symptomatic despite adequate rate control
Younger patients <60
Inadequate rate control despite beta-blocker/Ca antagonists + digoxin
Structural heart disease on ECHO
Co-existing HF
How can rhythm control be managed in patients with AF?
Direct current cardioversion
Antiarrhythmic drugs
Catheter ablation
What are class 1 antiarrhythmic drugs?
Na channel blockers
(Flecainide 100mg bd
Propafenone 150-300mg bd)
What are class 3 antiarrhythmic drugs?
K channel blockers –> prolong action potential duration/QT interval
Sotalol 80mg bd
Amiodarone 200mg OD
Give an example of a multichannel blocker that can be used in the management of AF
Dronedarone 400mg bd
Which veins can be the trigger of paroxysmal AF?
Pulmonary veins
What are the two ways of performing catheter ablation?
Radiofrequency current (burning)
Cryo-ablation (freezing)
In what patient group is catheter ablation more effective?
Structurally normal hearts
Minimal heart disease
In what proportion of patients is catheter ablation curative in:
a) paroxysmal AF?
b) persistent AF?
Paroxysmal - 65-80%
Persistent - 50-60%
Define endocarditis
Inflammation of the endocardium which results in vegetation formation and ultimately damage to the cusps of the valves