Infective Endocarditis Flashcards
What is Infective Endocarditis?
formerly called bacterial endocarditis
infection of endocardium Inner layers of heart)
or
heart valves
In Infective Endocarditis what bacteria commonly causes it?
Streptococcus and Staphylococcus
The heart is resistant to?
Infection
Why is the heart resistant to infection?
Because endocardial surface and constant blood flow make it difficult for organisms to adhere to cardiac tissue.
What two factors are typically required for endocarditis to develop?
- abnormality of the endocardium
- microorganisms in the bloodstream.
Which bacteria that are commonly found on the skin and upper respiratory tract- are frequent causative agents (80%-90%)?
Staphylococcus aureus and streptococci
Bacteria that can also cause infective endocarditis that is commonly found in the mouth is called?
Streptococcus viridans
Bacteria that can also cause infective endocarditis that is commonly found in the GI tract is called?
Streptococcus enterococcus
Endocarditis can also arise when?
- sterile platelet form
fibrin thrombi form
(on the endocardium or heart valves)
In endocarditis where do sterile plate and fibrin thrombi form?
On the endocardium or heart valve
The pathogenesis of this condition (infective endocarditis) occurs in which three stages?
- bacteremia (bacteria enters the bloodstream)
- adhesion (Adherence to damaged endothelium attracting Platelet and thrombi)
- colonization (Proliferation )
In Infective endocarditis Proliferation of the organism along with inflammation leads to?
vegetation (including platelets, fibrin, microorganisms, inflammatory cells, and granulomatous tissue)
What happens in the process of Vegetation?
- platelets
- fibrin
- microorganisms
- inflammatory cells
- and granulomatous tissue
collect on the internal structures because of damage from the infection
In Infective endocarditis what happens with each heart contraction?
Some of this vegetation is dislodged and ejected from the heart. These small thrombi move throughout the body, collecting in the microcirculation and creating microhemorrhages (e.g., petechiae and hematuria). The thrombi can also travel to other locations, in which case they are known as embolisms, and become lodged there.
During Infective endocarditis thrombi form that travels, this is called?
embolism
When there is an embolism (thrombi that form and travel), what does it cause?
-Microemboli
and
- Microhemorrhage
(Petechiae and hematuria)
Infective Endocarditis causes which life-threatening complications?
- myocardial infarction (MI)
- stroke
- Seizures
- pulmonary embolism (PE)
(caused by the emboli traveling outside the heart)
What happens to the heart valves with Infective Endocarditis?
They can become scarred and perforated
If untreated, infective endocarditis is usually fatal, especially when?
It involves the valvular structures
In most cases infective endocarditis occurs in which side of the heart?
Left side of the heart
Which risk factors render patients more vulnerable to the development of infective endocarditis?
- IV drug use (vegetation of the right side of the heart, tricuspid valve)
- valvular disorder
- prosthetic heart valves
- implanted devices ((pacemaker, internal cardioverter)
- rheumatic heart disease
- aortic coarctation
- congenital heart defect (tetralogy of Fallot))
- Marfan syndrome
- Immunodeficiency states
- Hypertrophic cardiomyopathy
In infective endocarditis, when there is vegetation of the right side of the heart. which valve is affected?
Tricuspid valve
Clinical manifestations of infective endocarditis include?
- flulike symptoms (fever, chills, myalgia)
- embolization
- heart murmur
- petechiae
- splinter hemorrhages under nails
- hematuria
- Osler’s nodes
- edema
- genway lesions
- Roth spots
A clinical manifestation of infective endocarditis is embolization. Provide examples of embolization.
- myocardial infarction (MI)
- pulmonary embolism (PE)
- transient ischemic attacks
- stroke
- splenic infarction
