Flashcards in Infective Endocarditis and Rheumatic Heart Disease Deck (65)
What is infective endocarditis?
Infection of the endocardium (inner layer of the heart)
What structures might be infected by infective endocarditis?
What is the change in the incidence and mortality of infective endocarditis in the last 30 years?
No change in either
What is the general prognosis and mortality of infective endocarditis?
What factors affect the prognosis and morality from infective endocarditis?
Underlying cardiac disease
Presence of complications
What professions are involved in the collaborative approach to treating infective endocarditis?
Primary care physicians
What is the incidence of infective endocarditis?
3-10 episodes per 100,000 person years in general population
14.5 episodes per 100,000 person years in 70-80 year olds
What is the difference in incidence of infective endocarditis between males and females?
Males : females
Is the prognosis worse in males or females?
What percentage of people infected with infective endocarditis will not have an underlying structural heart disease?
What are the potential epidemiologies of infective endocarditis?
Older patients with degenerative AS
Rheumatic heart disease
Health care associated
Mitral valve prolapse
Bicuspid aortic valve
Congenital heart disease
IV drug abuse
What are the potential pathophysiologies of infective endocarditis?
Adherence and invasion of non-bacterial thrombotic endocarditis
Mechanical disruption of valve endothelium
What are the possible causes of mechanical disruption of the valve endothelium?
Turbulent blood flow
What percentage of people with infective endocarditis will have a physically normal endothelium?
When might bacteraemia be present in infective endocarditis?
Invasive procedures e.g. oral, abdominal, genitourinary, intravascular catheters
How is infective endocarditis classified?
Acute, subacute or chronic
Early (< 1 year after surgery) or late (> 1 year after surgery)
Side of infection
What is right sided infective endocarditis associated with?
IV drug abusers
What are the presenting features of nosocomial/idiopathic infective endocarditis?
Signs and symptoms > 48 hours after hospitalisation
What are the presenting features of non-nosocomial infective endocarditis?
Signs and symptoms < 48 hours after hospitalisation plus healthcare contact
What factors might be associated with infective endocarditis?
Home-based nursing, IV therapy or haemodialysis < 30 days before onset
Acute care facility < 90 days before onset
Resident in nursing home or long-term care facility
What features might suggest infective endocarditis?
High index of suspicion
Non-specific symptoms e.g. fever, fatigue, malaise
What are the possible signs of infective endocarditis?
Congestive cardiac failure
Vascular or immunological phenomena
Immune complex deposition
Focal neurological signs
Peripheral embolus or abscess (30%)
Pulmonary embolus or abscess
What are the signs of immune complex deposition?
Vasculitic rash - diffuse, non-blanching, petechial, purpuric
Roth spots - retinal haemorrhages, white/pale centre, coagulated fibrosis
Osler's nodes - deep red spots, painful, raised, on finger plumps, palms and soles
Janeway lesions - flat, macular, echymotic, on palms and soles, non-tender
What should prompt a high index of suspicion?
Pyrexia of unknown origin when other diagnoses have been ruled out
Known IE causative organism isolated in culture
Congenital heart disease
New conduction disorder
When might signs of infective endocarditis be absent?
After antibiotic treatment
IE involving less virulent or atypical organism
What should be done in the investigation of suspected infective endocarditis?
Markers of infection/inflammation
Blood culture prior to starting antibiotics
What blood cultures should be taken in the investigation of infective endocarditis?
3 sets from different sites with > 6 hours in between
In severe sepsis or septic shock then take 2 sets of bloods from different sites within 1 hour
What is the standard echocardiography protocol in infective endocarditis?
Transthoracic 1st line imaging
If good quality TTE normal with low clinical suspicion then no TOE needed
If TTE normal with high clinical suspicion then TOE Needed
If TTE or TOE is normal but suspicion of IE remains high, repeat at 7-10 days
If TTE positive then do TOE for complications, abscesses and measuring size of vegetation
When should TTE and TOE be repeated?