mock 23 I.E. and A.S.
-
Pathology Valve replacement and haemodyasis
Stem1 : a 71 years old woman is admitted for defective aortic valve replacement. She presented 20 years previously with progressive aortic regurgitation and stenosis and underwent a tissue valve replacement 12 years ago
she has shown progressive symptoms related to degeneration of the tissue valve.- the original native valve is describe to have calcification and fibrosis , what are the two common causes for this ? At the age described .
1- Later degenerative changes due Rheumatic heart disease
2- Bicuspid aortic valve diseaseWhat is the physiology of stenosis or how stenosis happens?
Since this patient has bicuspid aortic valve
They will be calcifications—-> That cause valve thickening—-> Nodular fibrosis Fixed architecture- what non-surgical intervention could be considered for Pt with significant valve disease who are considered to have poor likelihood of cooping and open surgery ?
1-TAVR ( transcatheter aortic valve replacement )
2- Aortic valve Balloon valvuloplasty- what are the normal physiological mechanism related to hemostasis if a skin incision was made ? ( 3 marks )
1- Vascular spasm of the vessels
2- platelets aggregation at the site
3- coagulation pathway activation- metal prosthetic aortic valve is undertaken and old one was removed, complications happened, RBC transfusion. In Pt with prolonged duration of surgery and transfusion there’s risk of oozing from operation site.
Pathological process likely implicated?4 marks
1- DIC
2- hypothermia
3- Acidosis
4-heparin used in bypass surgery5) what test is used to assess Pt coagulation state ?
1-Thromboelastography (TEG)
2- clotting profile- what is Thromboelastography ( TEG ) ?
it’s a test to assesses the rapidity of clot formation around pin how long it will remain and how quickly it will undergo lysis
- when should blood products like FFP or platelets be used in coagulation state during surgery ?
usually with Pt suspecting coagulopathy: pre op guided by clotting profile and TEG
- during rewarming and transfer back into normal circulation, the Pt ECG is noted to be ischemic in one coronary artery, what’s the possible causes ?
1- air embolism
2- fragments from surgery tissue ( emboli )
3- plaque thrombosis—> atherosclerotic coronary thrombosis- in coronary artery circulation, if the coronary artery is fully blocked what are the consequence for the myocardial tissue?
MI ; type 2 , tissue necrosis due to loss of blood supply
- in what way does tissue necrosis in the heart differ from that in the brain ?
-In brain —> Liquefactive necrosis—>fluid necrosis
-In heart —> coagulative necrosis—>solid necrosis- cardiac tissue infract confirmed by serum troponin assay, what is troponin ?
-complex of protein involved in myofilament contracture being part of myocytes
- what part of the coagulopathy cascade is affected by warfarin ?
Affect in all pathways but mainly intrinsic pathway and common pathway
-
IE & AS
49 years old women referred for surgery replacement of her aortic valve she has one year history of palpitation and progressive cardiac failure.
There is no significant medical history but tobacco smoking four months post surgery she present with fatigue and arm weakness suspected infective endocarditis.- the original native valve is describe to have calcification and fibrosis , whatare the two common causes for this ? At the age described .
1- Later degenerative changes due Rheumatic heart disease
2- Bicuspid aortic valve diseaseWhat is the physiology of stenosis or how stenosis happens?
Since this patient has bicuspid aortic valveThey will be calcifications—>That cause valve thickening—->Nodular fibrosis
Fixed architecturewhy Bicuspid valve has risk ot sudden Death?
This Because of obstructive cardiac hypertrophy associated with risk of MI and arrhythmia .
surgical replacement is undertaken with metal prothesis what anticoagulant to be used post operatively in this patient ?
warfarin to stop thrombus formation by prothesis
how warfarin works ? mechanism of action ?
it works By inhibition of vitamin K dependant factor 10 9 7 2
in addition to routine investigations what investigations will help to give further information about cardiovascular system?
1. Cardiac catheterization
- Echo
what is vitamin K dependants factors ?
10 9 7 2
What is role of activating factor 10 in clotting ?
to activate Factor 2 which is prothrombin to active form Thrombin
what is normally help to activate Factor 10?
calcium
what is infective endocarditis ?
Infection usually bacterial process or vegitation localized in valve or valve replacement
What is hand sign in infective endocarditis?
Janeway lesion :no painful raised lesion due to septic imply emboli
Osler nodes: Painful raised red lesion due to immune complex position.
Splinter haemorrhage : tiny blood clots under nails
Clubbing : in long standingHow does infective endocarditis get into valve ?
Via haematogenous spread into thrombotic matter
Why arm weakness?
It is likely due to emboli to cerebral circulation from vegetation or infective thrombus
What is thrombus?
Product of clotting pathway and is blood clot that form in situ on the wall of blood vessel from constitution of the blood
What type of complications happens to non displace thrombus ?
Infection.
Inflammation.
Occlusion.What test you will do if you are suspected the thrombus is infected?
CBC
Inflammatory markers CRP ESR
Blood cultureWhat to look in the blood culture.?
Common, organisms like staph aurius, strep veridians
HACEK group which are homophiles species , aggrigobacter species
cardiobactrium species ,eikenella corrodens , kingellaWhy some cases of infective endocarditis develop heart block?
Because infective endocarditis will spread and extended into tissue around AV node
What is CRP?
Acute phase routine produce in response to inflammation
Where it produced?
In the liver
Why it raised in infective endocarditis?
Because it produces an increase amount following raised of interleukin 6 and 1 from macrophages
What is the commonest bacterial organisms can be found in infective
endocarditis?1 staph aurius
2 streptococcus veridansSituation is not settled and valve replacement was done why valve replacement?
Septic focus source
It will form biofilmValve histology show large amount of thrombotic matter with fungal elements
name two organisms?Candida albican.
AspirgalosisWhat is type of infective endocarditis is associated with adenocarcinoma?
Libman suck endocarditis
What is the pathological test to be used by surgical team to try to identify the septic agent?
1- repeated sample blood culture
2-aerobic and nonaerobic culture bottle for bothWhat is the antibiotic guideline inpatient was aortic stenosis?
Nice guideline no need for prophylactic antibiotic unless it is major surgery or high infected procedure
What would you see microscopically infective endocarditis?
Aschoff bodies which is granulomatous inflammation consist of central zone
degenerated ECM and infiltration lymphocytes plasma and activated macrophagesInvestigation of choice to identify vegetations in infective endocarditis?
2D echo (Transoesophageal or Transthoracic)
What to look for in 2D echo?
Valvular regurgitation
Leaflet: Prolapse, -annular dilatation
Chordal elongation
Increased echogenicity of sub valvular apparatus
Pericardial effusion
Ventricular dilatation and dysfunction
AbscessWhat is difference Mechanical vs Tissue valve
Mechanical - Warfarin for life, lasts long time
Tissue - may need replacing, doesnt need warfarin
Hello! It looks like you're interested in this conversation, but you don't have an account yet.
Getting fed up of having to scroll through the same posts each visit? When you register for an account, you'll always come back to exactly where you were before, and choose to be notified of new replies (either via email, or push notification). You'll also be able to save bookmarks and upvote posts to show your appreciation to other community members.
With your input, this post could be even better 💗
Register Login