Valvular heart disease Flashcards
What are the core symptoms of aortic stenosis?
Angina
Syncope
Heart failure
What symptom usually presents first in aortic stenosis?
Decreased exercise tolerance
Dyspnoea on exertion
What are the most common causes of aortic stenosis?
Age related calcification
Second most common cause is congenital bicuspid valve.
Rheumatic fever
Chronic kidney disease
How would you describe an aortic stenosis murmur?
Ejection systolic murmur that radiates to the carotids.
Presents as a crescendo-decrescendo murmur.
How would you diagnose aortic stenosis?
Echocardiography
When is surgery indicated for aortic stenosis?
If a patient is symptomatic
Asymptomatic severe AS with left ventricular systolic dysfunction
Asymptomatic severe AS with abnormal exercise test
Asymptomatic severe AS at the time of other cardiac surgery (eg. CABG)
What procedure should be considered in patients who have significant co-morbidities who require surgical intervention for aortic stenosis?
TAVI - Transcatheter aortic valve implantation
What pathological changes occur in a patient with chronic aortic regurgitation?
Left ventricular dilatation and resultedly heart failure.
What is the most common initial symptom in aortic regurgitation?
Exertional dyspnoea/reduced exercise tolerance.
What are the most common causes of aortic regurgitation?
Idiopathic
Degeneration of the valve - age related calcification
Rheumatic disease
Infective endocarditis
Marfans syndrome
How would you describe an aortic regurgitation murmur?
An early diastolic blowing murmur that is associated with a collapsing pulse and De Musset’s sign (head bobbing)
What is the management for patients with aortic regurgitation?
ACE inhibitor to reduce the after load
Surgery indicated in patients with:
- Symptomatic severe AR
- Asymptomatic severe AR with evidence of early LV dysfunction
- Asymptomatic AR with aortic root dilatation
What is the prognosis for mitral regurgitation?
Patients can have had it for years without ever knowing and often intervention is not required throughout life.
When is surgery indicated in patients with mitral regurgitation?
Symptomatic patients
Asymptomatic patients with mild-moderate LV dysfunction.
What pharmacological management can be used in patients with mitral regurgitation?
Diuretics
ACE inhibitors and beta blockers have been shown to be beneficial in patients with ischaemic disease.
What conditions can predispose a patient to suffering with infective endocarditis?
Mitral valve prolapse
Prosthetic valves
Rheumatic heart disease
Degenerative and bicuspid aortic valve disease
What are the most common causative organisms for infective endocarditis?
Staphylococcus aureus in the UK (due to IVDU)
Streptococcus viridans
If someone presents with infective endocarditis less than 1 year after having a prosthetic valve placed, what bacteria is this likely to be due to?
Coagulase negative Staphylococci
What are ‘late’ prosthetic valve infections commonly due to?
Streptococcus viridans
Staphylococcus aureus
Coagulase negative Staphylococci
When should you suspect infective endocarditis in a cardiac patient?
When a patient presents with an unexplained fever, bacteraemia or systemic illness and/or with a new murmur or other features of the illness.
What routine investigations should be carried out for patients with suspected infective endocarditis?
U+E LFT FBC Blood culture Urine dipstick analysis and MSU MC ESR CRP CXR ECG
What are the key diagnostic investigations for infective endocarditis?
Blood cultures and an transthoracic echocardiogram initially. However transoesophageal echocardiogram is more sensitive.
What are the requirements for diagnosis of infective endocarditis using blood cultures?
At least 3 sets of cultures should be taken from different sites over several hours. Antibiotics should be withheld if possible whilst these cultures are being taken.
What are the major criteria for diagnosis of infective endocarditis?
New valvular regurgitation
Blood cultures positive
Signs of endocardial involvement on the echocardiogram
Positive echo findings - eg. vegetations/abscess
Dehiscence of the prosthesis
What are the minor criteria for diagnosis of infective endocarditis?
Predisposing valvular or cardiac abnormality
IV drug user
Pyrexial >38oC
Embolic/vasculitis phenomenon
Blood cultures suggestive of atypical organism
Suggestive echo findings but not meeting the major criteria
How many major/minor criteria are required for a diagnosis?
2 major or one major and three minor or five minor criteria.
What is the management of a patient with infective endocarditis caused by the following
1) Streptococcus viridans
2) Staphylococcus aureus
3) Enterococcus faecalis
1) Viridans streptococci - benzylpenicillin IV plus low dose gentamicin. Vancomycin and gentamicin if the px is penicillin allergic
2) Flucloxacillin plus gentamicin
3) Amoxicillin IV plus low dose gentamicin
How should you monitor a patient with infective endocarditis?
Weekly echo’s
ECG twice weekly
Blood tests twice weekly
