Cardiac Infections Flashcards
What is infective endocarditis?
Infection of the endothelium of the heart valves
Factors which predispose patients to endocarditis
Heart valve abnormality (CHD, post rheumatic fever)
Prosthetic heart valve
IV drug users
IV lines
What is the pathogenesis of endocarditis?
Heart valve damage
Turbulent blood flow over roughened endothelium
Platelets/fibrin deposits
Bacteraemia
Organism settle in fibrin/platelet thrombi
(Usually left side)
What are the main organisms that cause endocarditis?
Staph aureus
Viridans streo
Enterococcus
Staphepidermis
Unusual organisms to cause endocarditis
“Atypical” organisms
Gram negatives
Fungi
Acute presentation of endocarditis
Overwhelming sepsis
Cardiac failure
Subacute symptoms of endocarditis
Fever Malaise Weight loss Tiredness Breathlessness
Subacute signs of endocarditis
Pyrexia New or changing heart murmur Finger clubbing Splinter haemorrhages Splenomegaly Roth spots, Janeway lesions, Osler's nodes Microscopic haematuria
Investigations for endocarditis
Blood culture
Echocardiogram
What is the most common causative in prosthetic valve endocarditis which is infected at the time of insertion?
Staph aureus
Staph epidermidis
What side is endocarditis more common in in IV drug users?
Right sided (tricuspid valve)
What is the most common endocarditis causing organism in IV drug users?
Staph aureus
what is the general native valve endocarditis treatment?
before blood culture
Amoxicillin
Gentamicin
What is the general treatment for prosthetic valve endocarditis?
(before blood culture)
Vancomycin IV
Gentamicin IV
Rifampricin PO
(Usually valve replacement required)
What is the first line treatment in drug user endocarditis?
before blood culture
Flucloxacillin IV
What antibiotic is staph aureus sensitive to?
Flucloxacillin
What antibiotics do you treat MRSA with?
Vancomycin IV
Rifampricin PO
What antibiotics is strep viridans sensitive to?
Benzyl penicillin
Gentamicin IV
What a tiptoes is enterococcus sensitive to?
Amoxicillin/ vancomycin IV
Gentamicin IV
What antibiotics is staph epidermis sensitive to?
Vancomycin IV
Gentamicin IV
Rifampricin PO
How long are IV antibiotics usually given for in endocarditis?
4-6 weeks
What should be monitored during endocarditis treatment?
Cardiac function
Temperature
CRP
What is myocarditis?
Inflammation of cardiac muscle
Symptoms of myocarditis
Fever
Chest pain
Shortness of breath
Palpitations
Signs of myocarditis
Arrhythmias
Cardiac failure
What are the main causative organisms in myocarditis?
Enteroviruses
- Coxsackke A & B
But other viruses possible (e.g. Influenza)
How is myocarditis diagnosed?
Viral PCR
Throat swab for influenza
Stool for Enteroviruses
What is pericarditis?
Inflammation of pericardium
Main feature of pericarditis
Chest pain relieved by sitting forward
Causes of pericarditis
Mainly viraln
Can be caused by bacteria after cardiothoracic surgery
Rarely secondary spread from endocarditis or pneumonia
Treatment of myocarditis and pericarditis
Supportive unless bacterial cause
In terms of cardiology what can staph epidermis infect?
IV lines
Prosthetic heart valves
