valvular heart disease Flashcards
describe the mitral valve?
Fibrous annulus, anterior and posterior leaflets, chordae, tendinae and papillary muscles
what is the most common cause of mitral stenosis?
- rheumatic heart disease secondary to previous rheumatic fever due to infection with group A beta-hemolytic streptococcus
- women > men
- inflammation-> commissural fusion and reduction in mitral valve orifice->doming pattern on echo -> thickening of valve, cusp fusion, calcium deposition, narrowed stenotic valve orifice and immobility of valve cusps
what are the other causes of mitral stenosis?
- Lutemacher’s syndrome
- Congenital mitral stenosis
- Carcinoid tumours metastasizing to lung or primary bronchial carcinoid
- what is the normal mitral valve orifice area
2. and what is it in a patient with mitral stenosis?
- 4-6cm2
2. <1cm2
describe the pathophysiology of mitral stenosis?
- mitral valve orifice reduced
- for cardiac output to be maintained the left atrial pressure increases and left atrial hypertrophy and dilatation occur
- increase in pulmonary venous, pulmonary arterial and right heart pressure increases
- development of pulmonary oedema especially when in AF and tachycardia
- this is prevented by alveolar and capillary thickening and pulmonary arterial vasoconstriction
- pulmonary hypertension causes right ventricular hypertrophy, dilation and failure with tricuspid regurgitation
where is the mitral valve located?
left side of the heart between atrium and ventricle
when will a patient with mitral stenosis start to experience symptoms?
- until valve orifice is moderately stenosed (area=2cm2)
- usually not till several decades after attack of rheumatic fever
what are the symptoms of mitral stenosis and what causes them?
- progressive severe dyspnoea (pulmonary venous hypertension and recurrent bronchitis)
- productive cough-blood, frothy sputum, frank haemoptysis
- weakness, fatigue and abdominal swelling due to right heart failure due to pulmonary hypertension
- palpitations due to large atrium and AF
what signs would be seen In the face of a patient with mitral stenosis?
malar flush (bilateral, cyanotic, dusty pink discolouration over upper cheeks due to arteriovenous anastomoses and vascular stasis
describe the pulse of a patient with mitral stenosis?
small volume pulse
usually regular
mostly in sinus rhythm but may develop AF
what signs would be seen in jugular veins in a patient with mitral stenosis?
- if right heart failure develops-obvious distension of jugular veins
- if pulmonary hyertension or tricuspid stenosis present then ‘a wave’ will be prominent
what signs would be noted on palpation in a patient with mitral stenosis?
tapping impulse felt parasternally on left
what would be the auscultation findings in a patient with mitral stenosis?
- loud first heart sound if mitral valve is pliable
- opening snap heard due to increased left atrial pressure, followed by a low pitched rumbling mid diastolic murmur (best heard when patient lies on left side)
- if in sinus rhythm-louder at end of diastole.
- severity of mitral stenosis is judged based on criteria
what criteria is used to judge the severity of mitral stenosis?
- presence of pulmonary hypertension (severe, right ventricular heave)
- closeness of opening snap to second heart sound proportional to severity
- length of mid-diastolic murmur proportional to severity
- as valve cusps become immobile the loud first heard sound softens and opening snap disappears
what investigations should be considered in a patient with mitral stenosis?
- CXR
- ECG
- echo
- cardiac magnetic resonance
- cardiac catheterisation
what are CXR findings in a patient with mitral stenosis?
- small heart and enlarged left atrium
- usually have pulmonary venous hypertension
- calcified mitral valve
- signs of pulmonary oedema
what are ECG findings in patients with mitral stenosis?
- in sinus rhythm will show a bifid p wave due to delay of left atrial activation
- AF usually present
- as disease progresses-ECG may show right ventricular hypertrophy (right axis deterioration and tall R waves in V1)
what is the purpose of echo in a patient with mitral stenosis?
- Determine left and right atrial and ventricular size and function
- Severity of mitral stenosis can be defined by planimetry of the mitral valve area.
- Wilkins score-determine if valve is suitable for percutaneous valvotomy
- Continuous wave doppler can estimate pulmonary artery pressure
what is the purpose of cardiac magnetic resonance in patients with mitral stenosis?
show mitral valve anatomy
describe the role of cardiac catheterisation in patients with mitral stenosis?
- only used if co-existing cardiac problem suspected
- Right heart catheterisaton may be required to determine pulmonary artery pressure
what are the treatment options for mitral stenosis?
- mild may not need treatment
- early symptoms such as mild dyspnoea can be treated with low dose diuretics
- pulmonary hypertension-surgical relief
- operative measures
what are the 4 operative measures used in treatment of mitral stenosis?
- trans-septal balloon valvotomy
- closed valvotomy
- open valvotomy
- mitral valve replacement
describe trans septal balloon valvotomy?
- Catheter into right atrium via femoral vein under local anaesthetic in cardiac catheter laboratory
- Interatrial septum is punctured and catheter advanced into left atrium and across mitral valve
- Balloon is passed over catheter to lie across the valve and inflated
- Can result in regurgitation and need valve replacement
what patients is trans septal balloon valvotomy good in?
Good for patients with pliable valves with little involvement of subvalvular apparatus and with minimal mitral regurgitation
what are the contraindications for trans septal balloon valvotomy?
heavy calcification or more than mild mitral regurgitaton and throbus
what patients is closed valvotomy used in?
For patients with mobile, non-calcified and non-regurgitant miral valves
describe the process of closed valvotomy?
- Fused cusps are forced apart by dilator introduced through apex of left ventricle
- Valve cusps often re-fuse and another operation may be needed
what is open valvotomy?
Cusps are carefully dissected apart under direct vision
describe the benefit of open valvotomy?
- often preferred to closed valvotomy
- requires cardiopulmonary bypass
- reduces likelihood of causing traumatic mitral regurgitation
when is mitral valve replacement necessary?
- Mitral regurgitation is present
- Badly diseased or badly calcified stenotic valve that cannot be reopened without producing significant regurgitation
- Moderate or severe mitral stenosis and thrombus in left atrium despite anticoagulation
how long can artificial valves work for?
> 20 years
what medications do patients require following mitral valve replacement?
anticoagulants to prevent thrombus formation
what is the most common cause of mitral regurgitation?
degenerative (myxomatous) disease, ischaemic heart disease, rheumatic heart disease and infectious endocarditis.
other than the most common causes what are the other causes of mitral regurgitation?
- can occur due to abnormalities of valve leaflets, the annulus, chordae tendineae or papillary muscles or left ventricle
- Also seen in diseases of myocardium (dilated and hypertrophic cardiomyopathy), rheumatic autoimmune disease eg systemic lupus erythematosus, collagen disesaes eg Marfan’s and ehlers-danlos syndromes and drug including centrally acting appetite suppressants and dopamine agonists
describe the pathophysiology of mitral regurgitation?
Regurgitation into left atrium produces left atrial dilation but little increases in left atrial pressure if long standing
Acute regurgitation-normal compliance of left atrial pressure rises so left atrial v-wave is increased and pulmonary venous pressure rises to produces pulmonary oedema. Since a proportion of stroke volume is regurgitated the stroke volume increases to maintain cardiac output and therefore left ventricle enlarges
what classification system can be used in mitral regurgitation?
Carpentier classification uses mitral leaflet motion to divide patients into classes according to mechanism of regurgitaton which is useful when considering surgery needed
when do patients with mitral regurgitation experience symptoms?
can be present for years with increased cardiac dimensions before symptoms occur
what symptoms may a patient with cardiac regurgitation experience?
- palpitation (due to increased stroke volume)
- dyspnoea and orthopnoea (due to venous hypertension)
- fatigue and lethargy (due to reduced cardiac output)
- late stages-symptoms of right heart failure and lead to congestive cardiac failure
- cardiac cachexia
- thromboembolism less common than mitral stenosis
- subacute infective endocarditis more common
what signs may a patient with mitral regurgitation experience?
- laterally displaced diffuse apex beat
- systolic thrill
- soft first heart sound (incomplete apposition of valve cusps and partial closure by ventricular systole)
- parasystolic murmur loudest at apex but radiating widely over precordium and axilla
- mid systolic click due to sudden prolapse of valve
- prominent 3rd heart sound due to rush of blood into dilated left ventricle in early diastole
what investigations should be carried out in a patient with mitral regurgitation?
- CXR
- ECG
- echo
- cardiac catheterisation
what may CXR show in a patient with mitral regurgitation?
left atrial and left ventricular enlargement
-increase in CTR and valve calcification
what would ECG show in a patient with mitral regurgitation?
hows features of left atrial delat (bifid p waves) and left ventricular hypertrophy (manifested by tall R waves in left lateral leads) and deep S waves in right sided precordial leads. Left ventricular hypertrophy occurs in about 50% of patients with mitral regurgitation. AF may be present
what would echo show in a patient with mitral regurgitation?
dilated left atrium and left ventricle. May be specific features of chordal or papillary muscle rupture. Assess the severity of regurgitation by colour doppler and looking at size of jet area and size of vena contracta and calculating regurgitant fraction, volume or orifice area. Observe dynamics of ventricular function. Transoesophageal echocardiography can be helpful to identify structural valve abnormalities before surgery
describe cardiac catheterisation in patients with mitral regurgitation?
prominent left atrial systolic pressure wave and when contrast is injected into the left ventricle it is seen regurgitating into an enlarged left atrium during systole
how is mitral regurgitation managed in mild cases?
in absence of symptoms can be managed conservatively and prophylaxis against endocarditis and serial echos
what intervention would be indicated if there was evidence of progression of mitral regurgitation?
early surgical intervention (mitral valve repair or replacement)
the advantages of surgery are diminished in more advanced disease
for patients with Mitral regurgitation who are unsuitable for surgery what management should be considered?
ACE inhibitors
diuretics
anticoagulants
percutaneous mitral valve repair
what is the aortic valve?
semilunar valve
between left ventricle and aorta
what is aortic stenosis?
- Chronic progressive disease producing obstruction to left ventricular stroke volume causing symptoms of chest pain, breathlessness, syncope, pre-syncope and fatigue
- calcific stenosis of a trileaflet aortic valve, stenosis of a congenitally bicuspid valve and rheumatic aortic stenosis
what is the commonest cause of aortic valve stenosis?
- calcific aortic valvular disease
- mainly in elderly-inflammatory process including macrophages and T lymphocytes with initially thickening of subendotheliam with fibrosis. Lesions contain lipoproteins which calcify, increasing leaflet stiffness and reduce systolic opening
what are the causes of aortic stenosis?
-calcific aortic valvular disease bicuspid aortic valve 1-2% of births associated with aortic dissection need regular echos -rheumatic fever-progressive fusion, thickening and calcification of aortic valve -chronic kidney disease -Paget's disease of bone -radiation exposure -homozygous familial hypercholesterolaemia
other than aortic stenosis what are the causes of obstruction to left ventricular emptying?
- supravalvular obstruction
- hypertrophic cardiomyopathy
- subvalvular aortic stenosis
describe the pathophysiology of aortic stenosis?
- Obstructed left ventricular emptying leads to increased left ventricular pressure and compensatory left ventricular hypertrophy
- Results in ischaemia of the left ventricular myocardium and angina, arrythmias and left ventricular failure
- Obstruction to emptying is more severe on emptying
- Normally exercise causes an increased cardiac output but due to narroeing of aortic valve orifice the cardiac output can hardly increase so BP falls, coronary ischaemia worsens, myocardial fails and cardiac arrythmias develop
- Left ventricular systolic function is typically preserved in patients with aortic stenosis
what are the symptoms of aortic stenosis?
- Usually none unless aortic stenosis is moderately severe
- Exercise induced syncope, angina and dyspnoea
- Once symptoms occur the prognosis is poor (death within 2-3 years with no surgical intervention
describe the pulse of a patient with aortic stenosis?
small volume
slow rising or plateau
describe precordial palpation in a patient with aortic stenosis?
apex not usually displaced because hypertrophy doesn’t produce noticeable cardiomegaly. Pulsation is sustained and obvious. Double impulse sometimes felt because of fourth heart sound or atrial contraction may be palpable. Systolic thrill may be felt in aortic area
describe what would be heard on auscultation in a patient with aortic stenosis?
ejection systolic murmur which is usually diamond shaped (crescendo-decrescendo). Murmur is usually longer when disease is more severe, as a longer ejection time is needed. Murmur is usually rough in quality and best heard in aortic area. Intensity of murmur is not a good guide to severity of condition as it is lessened by reduced cardiac output. In severe disease it may be inaudible. Other findings; systolic ejection click, soft or inaudible aortic second heart sound, reversed splitting of second heart sound, prominent fourth heart sound
what investigations should be done in a patient with aortic stenosis?
- CXR
- ECG
- echo
- cardiac catheterization
- cardiac magnetic resonance and cardiac CT
what would be seen on CXR in a patient with aortic stenosis?
relatively small heart with a prominent, dilated, ascending aorta. Due to turbulent blood flow above stenosed aortic valve produces so-called ‘post-stenotic dilatation’. The aortic valve may be calcified. CTR increases when heart failure occurs.
what would be shown on ECG in a patient with aortic stenosis?
left ventricular hypertrophy and left atrial delay. Left ventricular ‘strain’ pattern due to ‘pressure overload’ (depressed ST segments and T wave inverion leads orientated towards the left ventricle. Usually sinus rhythm but ventricular arythmias may be recorded
what would echo show in a patient with aortic stenosis?
thickened, calcified and immobile aortic valve cusps, presence of left ventricular hypertrophy and determine severity of aortic stenosis
describe the role of cardiac catheterization in patients with aortic stenosis?
rarely necessary as all information can be gained non-invasively with echo and CMR. Coronary angiography necessary before surgery
describe the role of cardiac magnetic resonance and cardiac CT in patients with aortic stenosis?
indicated for assessing thoracic aorta for presence of aneurysm, dissection or coarctation are rarely necessary
What patients with aortic stenosis should have aortic valve replacement
- symptomatic patients
- patients with BAV and ascending aorta >50mm or expanding at >5mm year
- asymptomatic patients with; symptoms during exercise test or BP drop, left ventricular ejection fraction <50%, moderate-severe stenosis undergoing CABG, surgery of ascending aorta or other cardiac valve
what are the treatment options for patients with aortic stenosis?
- antibiotic prophylaxis against infective endocarditis
- valvotomy (temporary relief from obstruction)
- balloon dilation-poor results
- percutaneous valve replacement (patients unstable for valve replacement
- transcatheter implantation with a balloon expandable stent valve
in what diseases does aortic regurgitation occur in?
Occur in diseases that affect aortic valve such as endocarditis and diseases affecting aortic root eg Marfan’s syndrome
describe the pathophysiology of aortic regurgitation?
Reflux of blood from aorta through the aortic valve into left ventricle during diastole.
If net cardiac output is maintained, the total volume of blood pumped into aorta must increase and so left ventricular size enlarges
Because of aortic runoff during diastole, diastolic BP falls and coronary perfusion is decreased.
The larger the left ventricular size is mechanically less efficient so that the demand for oxygen is greater and cardiac ischaemia develops
what are the symptoms seen in a patient with aortic regurgitation?
- Symptoms occur late only when left ventricular failure occurs
- Pounding of the heart-due to left ventricular size
- Angina
- Dyspnoea
- Arrythmias uncommon
describe the pulse in a patient with aortic regurgitation?
bounding or collapsing
what signs would be seen on palpation in a patient with aortic regurgitation?
apex beat displaced laterally and downwards and is forceful in quality
what are the auscultation findings in a patient with aortic regurgitation?
high pitched early diastolic murmur best heard at left sternal edge in the fourth intercostal space with patient leaning forward and the breath held in expiration. Because of the volume overload there is commonly an ejection systolic flow murmur.
what hyper dynamic circulation signs would be seen in a patient with aortic regurgitation?
- Quincke’s sign-capillary pulsation in nail beds
- De musset’s sign-head nodding with each heart beat
- Duroziez’s sign- to and fro murmur heard when feoral artery is ascultated with pressure applied distally
- Pistol shot femorals-sharp bang heard on auscultation over femoral arteries
what investigations should be done in a patient with aortic regurgitation?
- CXR
- ECG
- echo
- cardiac catheterisation
- cardiac magnetic resonance and cardiac ct
what would CXR findings be in a patient with aortic regurgitation?
features of left ventricular enlargement and dilatation of ascending aorta. Ascending aorta wall may be calcified in syphilis and aortic valve calcified if valvular disease is responsible for regurgitation
what would be ECG findings in a patient with aortic regurgitation?
features of left ventricular hypertrophy due to volume overload. Tall R waves and deeply inverted T waves in left sided chest leads and deep S waves in right sided leads. Normally sinus rhythm
what would be echo findings in a patient with aortic regurgitation?
vigorous cardiac contraction and dilated left ventricle. Enlarged aortic root. Diastolic fluttering of the mitral leaflets or septum occurs in severe aortic regurgitation. Severity-colour doppler.
describe the role of cardiac catheterisation in patients with aortic regurgitation?
assess coronary artery disease in patients requiring surgery. Injection of contrast medium into aorta will outline aortic valvular abnormalities and allow assessment of degree of regurgitation
describe the role of cardiac magnetic resonance and cardiac CT in patients with aortic regurgitation?
assess thoracic aorta in cases of aortic dilatation or dissection. Cardiac MR can be used to quantify regurgitant volume
describe the treatment for aortic regurgitation?
- treat underlying cause
- vasodilators and inotropes
- ACE inhibitors if patient has left ventricular dysfunction and beta blockers
- aortic surgery
when is aortic surgery indicated in patient with aortic regurgitation?
- acute severe aortic regurgitation
- symptomatic patients with chronic severe aortic regurgitation
- asymptomatic with left ventricular ejection fraction <50%
- asymptomatic with left ventricular ejection fraction >50% but with dilated left ventricle
- undergoing CABG, surgery of ascending aorta or other cardiac valve
where is the tricuspid valve?
between right ventricle and right atrium
what is tricuspid stenosis?
Uncommon, more frequent in women and usually due to rheumatic heart disease and associated with mitral and/or aortic valve disease. It is seen in carcinoid syndrome
describe the pathophysiology of tricuspid stenosis?
Results in reduced cardiac output which is restored towards normal when right atrial pressure increases. Resulting venous congestion causes hepatomegaly, ascites and dependent oedema
what are the symptoms of tricuspid stenosis?
- Symptoms due to associated left sided rheumatic valve lesions
- Abdominal pain due to hepatomegaly
- Swelling due to ascites
- Peripheral oedema
- These are quite severe when compared with the degree of dyspnoea
what signs would be seen in a patient with tricuspid stenosis?
- Unusual to be in sinus rhythm
- If in sinus rhythm-prominent jugular venous ‘a wave’
- Presystolic pulsation may be felt over the liver. Usually a rumbling mid-diastolic murmur, heard best at lower left sternal edge and louder on inspiration. May be missed due to murmur of co-existing mitral stenosis.
- Tricuspid opening snap may be heard
- Hepatomegaly, abdominal ascites, dependent oedema
what investigations are used in patients with tricuspid stenosis?
- CXR
- ECG
- echo
what would CXR findings be in a patient with tricuspid stenosis?
prominent right atrial bulge
what would ECG show in a patient with tricuspid stenosis?
enlarged right atrium shown by tall p waves
what would echo show in a patient with tricuspid stenosis?
thickened and immobile tricuspid valve but not as clearly seen as a abnormal mitral valve
what treatment is given to a patient with tricuspid stenosis?
- Medical management-diuretic therapy and salt restriction
- Tricuspid valvotomy occasionally possible
- Tricuspid valve replacement often necessary
- Other valves also need replacing as tricuspid stenosis is rarely isolated lesion
when does tricuspid regurgitation occur?
- Functional tricuspid regurgitation may occur whenever the right ventricle dilates (cor pulmonale, MI or pulmonary hypertension)
- Organic tricuspid regurgitation may occur with rheumatic heart disease, infective endocarditis, carcinoid syndrome, ebstein’s anomaly and other congenital abnormalities of the AV valves
what are the signs and symptoms of tricuspid regurgitation?
- Gives rise to high right atrial and systemic venous pressure
- Symptoms of right heart failure
- Large jugular venous ‘cv’ wave
- Palpable liver that pulsates in systole
- Right ventricular impulse may be felt at left sternal edge and a blowing pansystolic murmur best heard on inspiration at lower left sternal edge
- AF is common
- Echo-dilatation of right ventricle with thickening of the valve
what treatment is given to patients with tricuspid regurgitation?
- Usually disappears with medical management
- Severe organic tricuspid regurgitation may need operative repair (annuloplasty or plication)
- Tricuspid valve replacement is rarely needed
- In drug addicts with infective endocarditis of the valve-surgicak removal recommended
what is the pulmonary valve?
semilunar valve
between right ventricle and pulmonary artery
describe pulmonary stenosis?
- Usually a congenital lesion and rarely due to rheumatic fever or carcinoid syndrome
- Congenital – associated with intact ventricular septum or ventricular septal defect
- It can be valvular, subvalvular or supravalvular
- Multiple congenital pulmonary arterial stenoses due to infection with rubella during pregnancy
what are the signs and symptoms of pulmonary stenosis?
- Obstruction to right ventricular emptying causes ventricular hypertrophy leading to atrial hypertrophy
- Severe pulmonary obstruction – incompatible with life. But lesser extent can cause fatigue, syncope and symptoms of right heart failure
- Mild-may be asymptomatic
- Harsh mid systolic ejection murmur, best heard on inspiration to left od the sternum in second intercostal space. Associated with a thrill. Pulmonary closure sound is delated and soft. May be pulmonary ejection sound if obstruction is valvular. Right ventricular fourth sound and prominent jugular venous a wave are present when the stenosis is moderately severe.
- Right ventricular heave may be felt
what investigations are useful in a patient with pulmonary stenosis?
- Chest X-ray-prominent pulmonary artery due to post-stenotic dilatation
- ECG-both right atrial and right ventricular hypertrophy but may be normal even in severe cases
- Doppler echo-investigation of choice
what treatment is used in treatment of pulmonary stenosis?
Pulmonary valvotomy (balloon valvotomy or direct surgery)
what is the most common acquired lesion of the pulmonary valve?
pulmonary regurgitation
describe pulmonary regurgitation?
- Results from dilatation of pulmonary valve rich which occurs with pulmonary hypertension
- Characterised by decrescendo diastolic murmur, beginning with pulmonary component of the second sound that is difficult to distinguish from murmur of aortic regurgitation
- Usually no symptoms and usually no treatment is necessary
describe the basis of prosthetic valves?
The options for replacement are mechanical or tissue (bioprosthetic)
The valves consist of 2 basic components-opening allowing blood to flow through an occluding mechanism to regulate the flow.
describe mechanical prosthesis valves?
rely on artificial concluders; ball and cage (starr-Edwards), tilting disc (Bjork-Shirley) or double tilting disc (st jude)
describe tissue prosthetic valves?
derived from human or from porcine or bovine origin. A valve replacement from within the same patient (ie pulmonary to aortic valve) is termed autograft
what is pulmonary stenosis?
- Usually a congenital lesion and rarely due to rheumatic fever or carcinoid syndrome
- Congenital – associated with intact ventricular septum or ventricular septal defect
- It can be valvular, subvalvular or supravalvular
- Multiple congenital pulmonary arterial stenoses due to infection with rubella during pregnancy
what are the signs and symptoms of pulmonary stenosis?
- Obstruction to right ventricular emptying causes ventricular hypertrophy leading to atrial hypertrophy
- Severe pulmonary obstruction – incompatible with life. But lesser extent can cause fatigue, syncope and symptoms of right heart failure
- Mild-may be asymptomatic
- Harsh mid systolic ejection murmur, best heard on inspiration to left od the sternum in second intercostal space. Associated with a thrill. Pulmonary closure sound is delated and soft. May be pulmonary ejection sound if obstruction is valvular. Right ventricular fourth sound and prominent jugular venous a wave are present when the stenosis is moderately severe.
- Right ventricular heave may be felt
what investigations should be done in a patient with pulmonary stenosis?
- Chest X-ray-prominent pulmonary artery due to post-stenotic dilatation
- ECG-both right atrial and right ventricular hypertrophy but may be normal even in severe cases
- Doppler echo-investigation of choice
what treatment is used in pulmonary stenosis?
Pulmonary valvotomy (balloon valvotomy or direct surgery)
name systolic murmurs?
aortic stenosis
mitral regurgitation
name diastolic murmurs?
aortic regurgitation
mitral stenosis
tricuspid stenosis
describe murmurs heard in the aortic area?
ejection type murmur
aortic stenosis
flow murmur
describe murmurs heard in pulmonic area?
ejection type murmur
pulmonic stenosis
flow murmur
what murmurs can be heard at left sternal border?
early diastolic murmur
aortic regurgitation
pulmonic regurgitation
what murmurs could be heard in the mitral area?
pansystolic murmur-mitral regurgitation
mid to late diastolic murmur-mitral stenosis
what murmurs could be heard in the tricuspid area?
pan systolic murmur-tricuspid regurgitation/ventricular septal defect
mid to late diastolic murmur-tricuspid stenosis/ atrial septal defect
what is infective endocarditis?
Endovascular infection of cardiovascular structures including cardiac valves, atrial and ventricular endocardium, large intrathoracic vessels and intracardiac foreign bodies (prosthetic valves, pacemaker leads and surgical conduits)
describe the epidemiology of infective endocarditis?
- Incidence in UK – 6-7/ 100000
- More common in developing countries
- Without treatment mortality reaches 100% and with treatment there is still significant morbidity and mortality
what are the 2 factors that usually cause infective endocarditis?
- presence of organisms in bloodstream
- abnormal cardiac endothelium facilitating adherence and growth
describe how abnormal cardiac endothelium can lead to infective endocarditis?
- This promotes platelet and fibrin deposition which allows organisms to adhere and grow, leading to an infected vegetation. Valvular lesions may create non-laminar flow and jet lesions from septal defects or a patent ducus arteriosus resulting in abnormal vascular endothelium
- Aortic and mitra valves most commonly affected except in IV drug uses (right sided lesions more common)
what are the other causes of infective endocarditis?
- organisms
- rare-HACEK group of organisms-insidious course
- culture negative endocarditis 5-10% of cases
describe the clinical presentation of infective endocarditis?
Depends on causative organism and presence of predisposing cardiac conditions.
It may occur as acute, fulminating infection but can also be chronic or subacute with low grade fever and non specific symptoms
what would cause low clinical suspicion of infective endocarditis?
fever without any other factors
what would cause high clinical suspicion of infective endocarditis?
New valve lesion/murmur
Embolic event of unknown origin
Sepsis of unknown origin
Haematuria, glomerulonephritis, suspected renal infarction
Fever plus
- Prosthetic material inside heart
- Other high predisposition for infective endocarditis (drug use)
- Newly developed ventricular arrythmias or conduction disturbances
- First manifestation of congestive cardiac failure
- Positive blood cultures
- Cutaneous or ophthalmic manifestations
- Peripheral abscesses
- Predisposition and recent diagnostic/therapeutic interventions
what are the clinical features of infective endocarditis?
malaise clubbing murmurs heart failure arthralgia pyrexia skin lesions (oslers nodes, splinter haemorrhage, laneway lesions, petechiae) eyes (Roth spots, conjunctival splinter haemorrhage) splenomegaly cerebral emboli mycotic aneurysm haematuria
describe the duke major criteria for endocarditis?
- positive blood culture (viridian’s streptococci, abiotrophia, granulfcatella, streptococcus Bovis, HACEK,)
- persistently positive blood cultures
- positive serological test for Q fever
- echocardiogenic evidence of endocardial involvement
- new valvular regurgitation
describe the duke minor criteria for endocarditis?
- predisposition
- fever
- vascular phenomena
- immunologic phenomena
- microbiological evidence
- echocardiogram findings
what aetiology and sources of infection in infective endocarditis come from the mouth?
- dental disease or procedures
- alpha haemolytic streptococcus viridian’s
- account for 1/3 to 1/2 of cases
describe the differences between early and late native and prosthetic valve endocarditis and the organisms that cause them?
- early (poor prognosis)-within 60 days of valve surgery and acquired in surgery of soon after ICU-staph aureus and staph epidermis. poor outcome with MRSA
- late - more than 60 days after valve surgery, acquired in community (haematological spread)-strep viridian’s, staph aureus
what aetiology and sources of infection in infective endocarditis come from soft tissue infections?
- in diabetes and iv drug uses and patients with longterm catheters
- staphylococci
what aetiology and sources of infection in infective endocarditis come from the gut and perineum?
- underlying genitourinary disease or procedures
- prolonged hospitalisation- enterococci eg E. faecalis
- bowel malignancy-strep. bovis
what infective agent is usually the cause of infective endocarditis due to prolonged indwelling vascular catheters or IVDUs?
staph. aureus
candida
what is the role of investigations in patients with suspected infective endocarditis?
- confirm diagnosis
- identify organism
- monitor patient response to therapy
what investigations are useful in patients with suspected infective endocarditis?
-blood cultures
-serological tests
-FBC
-urea and electrolytes
-liver biochemistry
-inflammatory markers
-urine
-ECG
-CXR
transthoracic echo
-transoesophageal echo
what is the purpose of serological tests in patients with suspected infective endocarditis?
consider in culture negative cases for coxiella, bartonella, legionella, chlamydia
what would you expect to see in FBC in a patient with infective endocarditis?
reduced Hb
increased WCC
increase or decrease in platelets
what would you expect to see in urea and electrolytes in a patient with infective endocarditis?
increased urea and creatinine
what would liver biochemistry show in a patient with infective endocarditis?
increased serum alkaline phosphatase
what would inflammatory markers show in a patient with infective endocarditis?
increased ESR and CRP
What results would be shown in urine in a patient with infective endocarditis?
proteinuria and haematuria
what would ECG show in a patient with infective endocarditis?
PR prolongation/heart block associated with aortic root abscess
what would CXR show in a patient with infective endocarditis?
pulmonary oedema in left sided disease
pulmonary emboli/abscess in right sided disease
describe the role of transthoracic echo in a patient with infective endocarditis?
first line non invasive imaging test with sensitivity of 60-75%
demonstrates vegetations, valvular dysfunction, ventricular function, abscesses
describe the role of transoesophageal echo in patients with infective endocarditis?
second line invasive imaging test
greater sensitivity >90% and specificity
useful in suspected aortic root abscess and essential in prosthetic valve endocarditis
what treatment is given in a patient with infective endocarditis?
- Prolonged courses of antibiotics.
- Combination of antibiotics may be synergistic in eradicating infection and minimising resistance
- Take blood culture prior to antibiotic therapy
- Antibiotics taken for 4-6 weeks
- Monitor levels of gentamicin and vancomycin
- surgery may be needed
what may cause a patient with infective endocarditis to have persistent fever (not responded to treatment within 48 hours)?
- Perivalvular extension of infection
- Drug reaction
- Nosocomial infection
- Pulmonary embolism
infective endocarditis:
in the following clinical situation what IV antibiotic regimen should be started?
clinical endocarditis, culture results awaited, no staphylococci suspected
penicillin 1-2g 4 hourly
gentamicin 80mg 12 hourly
infective endocarditis:
in the following clinical situation what IV antibiotic regimen should be started?
suspected staphylococci (IVDU, recent intravascular devices, cardiac surgery, acute infection)
vancomycin 1g 12 hourly
gentamicin 80-120mg 8 hourly
infective endocarditis:
in the following clinical situation what IV antibiotic regimen should be started?
streptococcal endocarditis (penicillin sensitive)
penicillin 1.2g 4 hourly
gentamicin 80mg 12hourly
infective endocarditis:
in the following clinical situation what IV antibiotic regimen should be started?
enterococcal endocarditis
ampicillin/amoxicillin 2g 4 hourly
gentamicin 80mg 12 hourly
infective endocarditis:
in the following clinical situation what IV antibiotic regimen should be started?
staphylococcal endocarditis
vancomycin 1g 12 hourly OR flucoxacillin 2g 4 hourly OR benzylpenicillin 1.2g 4 hourly PLUS gentamicin 80-120mg 8 hourly
