gram positive in clusters is what organism
staph
is bacteria in the bloodstream a diagnosis
no it usually indicated that there is a focus of infection elsewhere in the body
what organism is commonly present on the flora of the skin
staphylococcus aureus and staphylococcus epidermidis
what layer of the heart is affected by endocarditis
endothelium ( of the heart valves)
what are predisposing factors to infective endocarditis
heart valve abnormality-calcification in elderly, congenital heart disease
prosthetic heart valve
intravenous drug users particularly right sided endocarditis
intravascular lines
what is the pathogenesis of endocarditis
the heart valve is damaged
turbulent blood flow over roughened endothelium
platlets/fibrin are deposited
bacteraemia 9may be very transient eg. dental treatment
organisms settle in fibrin/platlet thrombi becoming a microbial vegetation
which side of the heart is usually affected with infective endocarditis
the left side (aortic and mitral valves)
which organisms cause endocarditis on the native valve
staphylococcus aureus
viridians streptococci
enterococcus
staphylococcus epidermidis
name some atypical causes of endocarditis
bartonella, coxiella burnetti, chlamydia, legionella, mycoplasma, brucella
gram negatives
fungi
where is the foramen ovale in the heart
between the right and left atrium
how is the patency of the ductus arteriosus maintained in the foetus
circulating prostaglandin E2 which is produced by the placenta
which is the most common type of congenital heart defect
VSD
what are the problems associated with VSD
pulmonary blood flow increases
what will a small VSD produce (sound)
a loud pan-systolic murmur
what signs and symptoms will a large VSD cause
may show prominent pulmonary arteries on xRAY
may show cardiomegaly
may result in significant LA and LV dilatation
heart failure symptoms in childhood
pulmonary hypertension and Eisenmenger’s complex
what is a small VSD also known as
maladie de Roger
are ASDs more common in women or men
2-3 times more common in women than men
what signs and symptoms are associated with ASD
right heart overload and dilatation
dyspnoea and exercise intolerance
may develop atrial arrhythmias from right atrial dilatation
pulmonary hypertension
volume overload in RV
right ventricular heave can usually be felt
what is PDA (patent ductus arteriosus)
persistent communication between the proximal left pulmonary artery and the descending aorta resulting in a continuous left to right shunt
what can help stimulate the close of a patent ductus arteriosus
indomethacin
what signs are associated with PDA
bounding pulse
continuous ‘machinery murmur’
as pulmonary hypertension develops in a large PDA murmur becomes softer
what happens in tetralogy of fallot
large malaligned VSD
an overriding aorta
right ventricular outflow tract obstruction
right ventricular hypertrophy
what do the symptoms of tetralogy of fallot often depend on
degree of pulmonary stenosis
what syndrome is associated with tetralogy of fallot
DiGeorge syndrome
what does the closure of the ductus arteriosus result in
a fibrous ligament the ligamentum arteriosum
how does a right bundle branch block affect the axis of the heart
it has no effect
what does right bundle branch block cause
splitting of the second heart sound
what does right bundle branch block look like on the ECG
tall R waves in VI and deep S waves in lead 1 and v6
what does left bundle branch block look like on ECG
tall R waves in lead 1 and V6 and deeps S waves in VI