Vascular and Ischaemia Heart Disease Flashcards
What is infarction?
Ischaemic necrosis due to occlusion/reduction of blood flow
What is Ischaemia?
Impaired vascular perfusion
Why can slow, turbulent flow result in thrombus?
Platelets contact endothelium
Active clotting factors not diluted due to less flow
Anticoagulant inflow slowed
When does slow, turbulent flow arise?
DVT Fibrosed-myocardium post MI Aneurysms AF MS and LV dilation
What are lines of Zahn?
Alternating platelet + fibrin/RBC + WBC bands
What occurs in a mural thrombus?
Forms in ventricles
- MI
- Arrhythmias
Forms in aorta
These adhere to the wall of large vessels and typically show lines of Zahn
How do venous thrombi appear?
Reddish-blue and adhered to wall
What types of embolism exist?
Thromboembolism Fat Marrow Air Septic Amniotic fluid Tumour
What shape is a pulmonary infarct?
Wedge shaped
How could a venous embolus infarct peripheral arteries? What would this phenomenon be called?
ASD/VSD
Paradoxical embolus
When would a fat embolism occur?
Major soft tissue/bone injury
- Fat enters lung globules
Arteriosclerosis is a general term for three conditions. What are they?
Atherosclerosis
Monckeberg Medial Calcific Sclerosis - Medium vessels
Arteriolosclerosis - Small vessels
Where is atherosclerosis common?
Aorta
Coronary arteries
Cerebral arteries
What is the basic structure of the atheromatous plaque?
Lipid core
Fibrous cap
How can an atheromatous plaque lead to an aneurysm?
Media progressively degraded
Vessel wall weakens
What are the key stages to atherosclerosis?
- Chronic endothelial injury
- Endothelial dysfunction
- Macrophage activation
- Lipoprotein oxidation
- Foam cell formation
- Plaque formation and growth
(7. Distribution)
What are some haematological risk factors for DVT and PE?
Polycythaemia rubra vera Thrombocytosis Hyperhomocysteinaemia Antithrombin deficiency Protein C/S deficiency
Symptoms and signs of DVT?
Calf/leg
- Pain
- Swelling
- Redness
- Hot
What investigations can be done into a DVT?
D Dimers - Rule out, not rule in
US Doppler
What is venous plethysomography and how does it work?
Strain gauge around affected limb
Venous emptying by compression
If there is slow refill = clot
Treatment for DVT
LMWH/Warfarin Compression stockings (TEDs for 6 weeks)
What is phlegmasia dolens?
A highly severe DVT
Results in reliance on superficial venous drainage
Blood gathers in limb
Blocks arterial inflow
Symptoms of PE?
Dyspnoea Syncope Pleuritic chest pain Haemoptysis Sudden death
Imaging for PE
CXR
V/Q scan
CTPA - Breath holding needed
Echo
What is the BNF regimen for tPA?
- 10mg bolus over 2-5 minutes
- 90mg infusion over 2 hours
- Max 1.5mg/kg if <65kg
What are some examples of oral anticoagulants?
Dabigatran (Antithrombin)
Apixaban, Rivaroxaban (anti-Xa)
Which is the preferred therapy in pregnancy, warfarin, heparin or LMWH?
Heparin
How is heparin dosing monitored?
Activated partial thromboplastin time (APTT)
What is the duration of PE therapy?
If temporary risk factor present - 4-6 weeks If idiopathic PE - 3-6 months (longer the more distal) Second idiopathic event - Lifelong
Common presentation of angina
Heavy chest pain Possible radiation Exacerbation by exertion/stress/cold wind Relieved by resting/GTN Risk factors present
Presentation of aortic dissection/pericarditis
Pleuritic
Focal pain
No pattern - at rest
No risk factors
Central chest pain relieved by sitting forward is typically?
Pericarditis
Sharp focal chest pain exacerbated by breathing?
Pleuritic pain
- Aortic dissection (tearing)
- PE (dull)
What investigations can be done into chest pain (not MI)?
Exercise testing
Perfusion imaging
CT angiography
Angiography
What vessels are harvested during a CABG?
Long saphenous vein
Internal mammary artery
What incision is made for a CABG?
Median sternotomy
What is PCI and what is its alternate name?
Percutaneous Coronary Intervention
Coronary angioplasty
When is PCI used?
In a STEMI
What drug therapy is used during a PCI?
Dual antiplatelet therapy (aspirin and clopidogrel)
Anticoagulants
What is claudication?
Intermittent leg pain due to muscle Ischaemia during exercise
What is ABPI and what are the values in
- A normal individual
- A patient suffering from claudication
- Patient with severe claudication
Ankle Brachial Pressure Index
- 0.9-1.2
- 0.4-0.85
- <0.4
What symptoms are indicative of critical limb Ischaemia?
Rest pain - toe/foot ischaemia while sleeping/lying down
Ulcers and gangrene if very severe - due to trauma
Worse at night
Helped by putting dependence on leg/walking
Pathogenesis of aortic aneurysm?
Elastin/Collagen regulation in wall
Aneurysmal dilation
Increased aortic wall stress
Progressive dilation - Tension
Symptoms of an abdominal aortic aneurysm?
Tachycardia
Hypotension
Pulsatile, expansile mass
Transmitted pulses
What investigations can be done into an AAA?
USS
CT Scan - Arterial phase
What are varicose veins?
Dilated, tortuous superficial veins
Due to deep vein pressure
What signs suggest varicose veins?
Visibility of veins - more prominent when standing
Complications
- Bruising
- Thrombophlebitis
Differential diagnoses for a stroke?
Hypoglycaemia Seizure Migraine Tumour Function hemiparesis
Medical management of a stroke
Aspirin 75mg + Dipyridamole (modified release) 200mg twice daily
Clopidogrel 75mg once daily
Statins
If in AF - Anticoagulants
If hypertensive - Perindopril + Indapamide
