13. Cardiovascular Infections Flashcards
What is endocarditis?
Infection of the endocardial surface of the heart
Classify endocarditis
Native valve endocarditis (hospital vs community acquired)
Prosthetic valve
IV Drug users
Where is the most common location for endocarditis in IV drug users?
Tricuspid valve
What are the risk factors for endocarditis?
Surgery of GIT, GU, URT
Indwelling devices
Dental and tonsillectomy
What patient factors are risks for endocarditis?
Heart lesions
IV Drug use
Animal exposure
Dialysis, chronic liver disease, malignancy
What heart lesions increase the risk of endocarditis?
Prosthetic valves
Previous endocarditis
Patent ductus arteriosus (turbulence)
Valve diseases
Give the pathogenesis of endocarditis
Defect or lesion causes turbulent flow
Turbulent flow causes damage to endocardial surface, which platelets and fibrin stick to
BSI
Bacteria stick to platelets and fibrin and form a vegetation
Which are the most common pathogens involved in endocarditis?
Staph and strep
What are rarer pathogens in endocarditis?
Chlamydia Q fever Brucella Legionella Mycoplasma HACEK organisms Fungi
What are the clinical features of endocarditis?
Non specific infection: low grade fever, chills, rigors, night sweats, malaise, fatigue, weight loss, arthralgia, myalgia
Resp symptoms in right sided
What are the immunological features of endocarditis?
Osler’s nodes
Roth spots
What are the embolic manifestations of endocarditis?
Splinter haemorrhages
Pulmonary infarctions
Ischaemic limb
Stroke
How is infective endocarditis diagnosed?
3 blood cultures 1 hour apart
Transoesophageal echo
Serology, PCR, ESR, urinalysis, FBC
Culture of any valves removed
What set of criteria determines the likelihood the patient has infective endocarditis?
Modified Duke Criteria
What are the major Dukes criteria?
Positive cultures and imaging
What are the minor Dukes criteria?
Risk factors
Fever
Vascular or immunological criteria
Micro evidence
What combinations of criteria mean a patient definitely has infective endocarditis?
2 major
1 major and 3 minor
5 minor
What combinations of criteria mean a patient has a possible infective endocarditis?
I major and 1 minor
3 minor
What are the steps in the management of infective endocarditis?
Confirm aetiology
Help from micro
Combo of antibiotics for 4-6 weeks
Consultation with cardiac surgery
How can endocarditis be prevented?
Avoid bacteraemia
Reduce rates rheumatic fever
Dental hygiene in at-risk patients
Antibiotic prophylaxis in high risk patients
What is pericarditis?
Inflammation of the pericardium, often accompanied by effusion (which can be seen on CT)
What pathogens can cause pericarditis?
Coxsackie, influenza, adenovirus
Staph, strep, chlamydia, TB
What are the clinical features of pericarditis?
ECG changes: ST elevation or PR depression
Acute chest pain, resolved when sitting up and leaning forward
Pericardial friction rub
Systemic infection signs
What is the treatment of pericarditis?
Drain effusion (serology/culture)
restrict activity
NSAIDs, colchicine, steroids
Antimicrobials if bacteria identified
What are the causes of myocarditis?
Coxsackie, influenza, COVID-19
Diphtheria
Toxoplasmosis
What are the features of myocarditis?
Increase in troponin
ECG changes
Acute chest pain
SOB, fatigue, palpitations, arrhythmia
What is the treatment of myocarditis?
Manage sequelae (heart failure and arrhythmia) Avoid exacerbating Antimicrobial if bacteria identified
What should be avoided in myocarditis?
NSAIDs, exercise, alcohol
What are the features of device infections?
Local cellulitis, BSI, endocarditis
What is a vascular infection?
Infection from grafts
Why can enteric bacteria contaminate grafts?
Grafts are often put in around the groin
