Cardiovascular Flashcards
How do you assess direction of polarisation and axis deviation on an ECG
R wave shows direction of polarisation, should increase V1-4 (S waves increase V1-3 then decrease)
Axis should be directed towards lead II (most positive deflection)
Left axis Leaves II and III (I only positive, aVF negative), Right axis Returns to II and III (I only negative, aVF positive)
Describe the depolarisation of heart cells
HEART CELL DEPOLARISATION: SLOW ENTRY OF SODIUM IONS TO CAUSE MEMBRANE POTENTIAL TO RISE FROM -60 TO -40mV, SPONTANEOUS DEPOLARISATION, CALCIUM ENTER CAUSING STRONGER DEPOLARISATION TO +5mV, POTASSIUM CAUSES REPOLARISATION BACK TO -60mV (CALCIUM AND POTASSIUM CHANNELS CLOSE)
What parts of the clotting process do different anticoagulants affect
(Platelet aggregation)
Aspirin inhibits COX-1 and therefore thromboxane A2, less activation and aggregation
P2Y12 inhibitors (clopidogrel, prasugrel, ticagrelor), reduce ADP, less activation and aggregation
(Coagulation cascade)
Warfarin inhibits vitamin K - reduces II, VII, IX, X
Heparins increase antithrombin, inactivates thrombin and Xa, thrombin means less conversion of fibrinogen
DOACs: majority direct and reversible inhibitors of Xa, dabigatran inhibits thrombin
Decsribe CHA2DS2VASc
CHA2DS2VASc (stroke assessment): =2 anticoagulant (=1 for men consider)
Chronic HF, hypertension, age >75 - 2, diabetes, stroke / TIA - 2, vascular disease, age 65-75, sex category female
2 = 2% stroke risk per year
Describe the presentation of angina / IHD
Chest pain - tight, stab/ belt/ heavy, middle of chest
May radiate to one or both arms, neck, jaw, teeth
Breathless, palpitations, presyncope (sensation you are going to faint)
Very exercise related
How is IHD diagnosed and what investigations are used
Diagnosis usually entirely from history
Primary care: ECG, haemoglobin, lipid profile, glucose / HbA1c
CT coronary angiogram gold standard, contrast used, assess flow of coronary arteries
Determine if obstructive coronary artery disease. If left main stem or severe 3 vessel disease → coronary angiography
ECG - usually normal, may show ST depression, flat/ inverted T waves
Cardiac stress test (exercise or dobutamine), monitor with ECG, ST depression = late stage. Many patients unsuitable
Describe the ECG changes in acute coronary syndrome
STEMI: ST elevation and new left bundle branch block (wide QRS, V1-6), hyperactive T waves, pathological Q waves
NSTEMI: ST depression and T wave inversion
Pathological Q waves present after 6h of symptoms in full thickness infarction
Specific arteries: left coronary - anterolateral (I, aVL, V3-6); LAD - anterior (V1-4); circumflex - lateral (I, aVL, V5-6); right coronary - inferior (II, III, aVF)
Unstable angina usually has normal ECG
Describe the management of angina / IHD
Lifestyle advice
All patients aspirin (clopidogrel if contraindicated) and a statin, dual therapy with aspirin + clopidogrel / rivaroxaban in patients ACS or undergoing PCI
If required also antihypertensives (target 120-130) - ACE / BB / ARB; antidiabetic drugs
Symptom relief: GTN spray, beta blocker, calcium channel blocker, long acting nitrate
Surgery when medical not working, PCI and CABG
Why are antiplatelets the main stay of treatment in acute coronary sundrome
When a thrombus forms in a fast flowing artery it is mainly formed by platelets
What is the presentation of ACS
Acute chest pain lasting longer than 20 mins, at rest, ⅓ in bed at night
Can radiate to left arm, jaw, neck. Does not respond to GTN
Sweating, nausea, vomiting, breathless, palpitations, anxiety, sense of impending doom
Significant hypotension. brady/ tachycardia
Describe the investigations for ACS
Immediate ECG, coronary angiography (within 12h)
Bloods: troponin, glucose, FBC, U+Es, (CRP + lipids)
How is a STEMI acutely managed
300mg aspirin + prasugrel / clopidogrel, IV morphine, ondansetron (add O2 and IV GTN if required)
Assess if PCI suitable - within 12h of onset / 2h of when fibrinlysis could be given without contraindications (IV unfractioned heparin in surgery)
Otherwise thrombolysis with alteplase / tenecteplase
How is risk of NSTEMI assessed
GRACE score: age, HR, systolic, creatinine, cardiac arrest at admission, ST deviation, abnormal cardiac enzymes, killip class (no CHF, rales / JVD, pulmonary oedema, cardiogenic shock)
How are NSTEMIs acutely managed
Grace score
High risk: coronary angiography +- revascularisation, 300mg aspirin + prasugrel / clopidogrel. If required: O2, morphine, GTN, ondansetron, heparin (fondaparinux)
Low risk: same as above but surgery not required if 6m mortality below 3%
How are patients managed following an MI
Echocardiogram to assess LV function, cardiac rehabilitation (lifestyle)
Secondary prevention - continue dual antiplatelet, ACE inhibitors / ARB, beta blockers / rate limiting CCB, statins. If HF: spironolactone + dapgliflozin
Define heart failure
Heart failure is caused by a structural and/or functional abnormality that produces raised intracardiac pressures and/or inadequate cardiac output at rest and/or at exercise
Describe the pathophysiology of heart failure
When drop in arterial pressure in aorta/ heart, baroreceptors activate sympathetic nervous system. In heart failure there is chronic activation, effect is diminished, cardiac output stops increasing
Impaired LV function leads to backlog of blood, LA / pulmonary veins have increased volume + pressure, fluid leaks out
How do you investigate heart failure (what do they show)
Transthoracic echocardiogram, ECG, CXR, NT BNP blood test; also: troponin, FBC, U+Es, HbA1c, LFTs, TFTs, CRP
Exercise stress testing, (CT) coronary angiogram
NT-proBNP blood test increased, echocardiogram - chamber size, valvular disease, MI
<400pg/mL HF unlikely, 400-2000 transthoracic doppler + specialist within 6 weeks, >2000 within 2 weeks + poor prognosis
X ray (ABCDE): Alveolar oedema (batwing), Kerley B lines (horizontal - peripheral lungs), Cardiomegaly, Dilated upper lobe vessels, pleural Effusion (costophrenic blunting)
ECG - ischaemia, MI, LV hypertrophy
How is heart failure classified
NYHA Classification: I - no limitation (asymptomatic), II - slight limitation, III - marked limitation (symptoms on minimal exertion), IV - inability to carry out physical activity
How is heart failure managed
Treat cause, lifestyle (avoid large meals (workload, sodium - water retention), vaccination)
Management ABAL: ramipril (ACE) (evidence sacubitril / valsartan better), bisoprolol (BB), spironolactone (aldosterone antagonist), furosemide (loop)
Symptoms persist - specialist: amiodarone, digoxin, sacubitril + valsartan
Avoid ACE if valve pathology
Calcium channel blockers and dihydropyridines (nifedipine) avoided in reduced
Comprehensive therapy (abs vp): aldosterone antagonist + beta blocker + sacubitril-valsartan + dapagliflozin (SGLT2 inhibitor)
Preserved ejection fraction (specialist): dapagliflozin, furosemide if still fluid overload
What are the causes of secondary hypertension
ROPED: renal disease, obesity, pregnancy induced / preeclampsia, endocrine, drugs
Most common causes: renal (CKD, renal artery stenosis, nephritis), sleep apnoea, coarctation of aorta
How is hypertension managed including different demographics
ACD pathway - ACE inhibitor (or ARB), calcium channel blocker, diuretics (thiazides then loop)
Ramipril (candesartan), nifedipine, bendroflumethiazide (furosemide)
Beta blockers are not first line but consider in young people
If 55+ or Afro-Caribbean likely low renin, calcium channel blocker first and ARB instead of ACE
In diabetics: ACD no matter the age
What causes supraventricular tachycardia and how does it present on ECG
Electrical signal reneters the atria from the ventricles, causes another depolarisation and repeats
Presents with narrow complex tachycardia (< 0.12s or 3 small squares) followed immediately by T wave, P waves usually buried by T waves. HR > 150
How do atrial flutter, AV block and L / R BBB present on ECG
Atrial flutter - organised sawtooth waves, regular QRS, two P waves for every QRS
AV block - long PR, 1st - PR and QRS associated, 2nd slightly associated (Mobitz I PR progressively prolonged until dropped, II PR constant but not always followed by QRS), 3rd no association between P and QRS
Left bundle branch block (wiLLiam) - ‘w’ shape in V1 + ‘m’ shape in V6, broad QRS, prolonged / broad R wave in V5/6, dominant S wave in V1, absence of Q waves in lateral leads
Right bundle branch block (moRRow) - ‘m’ shape in V1 + ‘w’ shape in V6, broad QRS, slurred S waves in lateral leads
How do you manage tachycardias
Tachycardia: beta blockers and calcium channel blockers. AV node reentry tachycardia most common - catheter ablation. If systolic < 90 - DC cardioversion
Supraventricular T: adenosine, verapamil (can’t be given with BB)
Broad complex: IV amiodarone, DC cardioversion (haemodynamically unstable)
How is AF investigated
ECG: irregularly irregular, absent P waves, narrow QRS
Echo to see if structural
Bloods: FBC, U+Es, TFTs, LFTs, clotting profile
Also CHADSVasc and ORBIT
How is AF managed
Acute: haemodynamically unstable - electrically cardioverted, stable and <48h rate / rhythm, >48h rate control
Rate or rhythm: rate control FL unless: AF reversible, new onset within 48h, HF caused by AF.
Rate (ventricular): beta blocker (atenolol) or rate limiting CCB (verapamil, diltiazem) (avoid in HF), digoxin if unsuitable, dual therapy
Rhythm (sinus): cardioversion + long term rhythm control, beta blocker FL, dronedarone SL (or amiodarone (LV impairment / HF), consider left atrial ablation
Cardioversion is immediate if <48h or haemodynamically unstable; electrical (defib under sedation), pharmacological - flecainide, amiodarone
Both ineffective or not tolerated: LA ablation, AV node ablation + pacemaker
DOAC for clots, warfarin if DOAC contraindicated, both contraindicated - consider left atrial appendage occlusion
Describe the different types of heart block
First degree (PR + QRS still associated): PR interval >0.2s. Usually asymptomatic and does not need to be treated, slower conduction time, age, myocarditis, hypothyroidism, medications
Second degree (slightly associated): Mobitz I: progressively prolonged PR until beat dropped; Mobitz II: PR is constant but P wave often not followed by QRS
Intermittent blockage of waves, usually a structural change: IHD, fibrosis, degeneration of AV node. MII has higher risk of progression to complete block
Third: no association between P and QRS. Atria and ventricles beat independently (atria usually quicker), damage to AVn or bundle of His, MI, congenital
What are the 3 presentations of peripheral arterial disease
Intermittent claudication: cramping in leg, due to exertion, relieves with rest
Acute limb ischaemia (6 Ps): pain, pallor, pulseless, paralysis, paraesthesia, perishing cold
Leriche syndrome: thigh / buttock claudication, absent femoral pulses, male impotence (occlusion of distal aorta / common iliac)
What is Virchow’s triad, what is the difference between arterial and venous clot formation, what are the risk factors for VTE
Virchow’s triad for clot formation - stasis of blood flow (longer contact), endothelial injury (exposed collagen and stimulates), hypercoagulation
Arterial platelet driven, inflammation/ trauma/ infection. Venous fibrin driven, stasis usually issue
RF: immobility, recent surgery, cancer, long haul travel, pregnancy, oestrogen, polycythaemia, SLE, thrombophilias
What are the signs and examination tests for PAD and DVT
Signs: skin pallor, cyanosis, dependent rubor, muscle wasting, hair loss, ulcers, poor wound healing, gangrene, reduce skin temp + sensation, prolonged CRT, changes in Buerger’s
Buerger’s: lie supine with legs at 45 degrees, hold for 1-2m looking for pallor. Sit patient up with legs hanging; healthy will go pink, PAD will go blue then dark red (rubor)
leg pain / tenderness, swelling (pitting oedema), dilated veins, warm, erythema, ulcers
Measure calf circumference 10cm below tibial tuberosity, >3cm bigger than other - positive
How is PAD investigated and treated
PAD: ankle-brachial index only necessary. Duplex US and angiography for flow and surgery
Ratio of systolic in ankle vs arm 0.9-1.3 healthy, 0.6-0.9 mild, 0.3-0.6 moderate, <0.3 severe
Non limiting claudication: aspirin / clopidogrel, exercise therapy, lifestyle changes; lifestyle limiting add: cilostazol (several cardiac contraindications) or naftidrofuryl, surgical revascularisation
Acute limb ischaemia: emergency, endovascular or surgical revascularisation + thrombolysis / amputation, aspirin / clopidogrel + heparin, appropriate analgesia
How is DVT investigated and treated
DVT: Well’s score, D-dimer blood test (sensitive not specific), duplex ultrasound (CT/MRI venography), bloods (FBC, LFTs, U+Es, clotting profile)
Well’s score: likely - US, unlikely - d-dimer
DVT: apixaban / rivaroxaban FL (start as soon as suspected), enoxaparin / dalteparin SL (FL in pregnancy), exercise, compression stockings
Long term anticoagulants for unprovoked, 3m for reversible cause, 3-6m cancer
What are the causes of pericarditis
Majority are idiopathic and seen in young adults
Range of pathogens (viruses, bacterial and some fungal)
Noninfectious: Sjorgen’s, rheumatoid arthritis, SLE, secondary metastatic tumours, trauma, iatrogenic, MI, uraemia
How does pericarditis affect the function of the heart
Effusion commonly occurs with pericarditis, if volume large enough ventricular filling is compromised (tamponade), reduces diastole and therefore systole - requires emergency drainage
How does pericarditis present
Chest pain - severe, sharp + pleuritic (not crushing), rapid onset, worse lying flat (alleviated by sitting up), left anterior chest (radiates to arm/ trapezius ridge)
Low grade fever and prodrome of myalgia
Pericardial rub on auscultation (rubbing / scratching)
How is pericarditis investigated
ECG - PR depression, global saddle shaped ST elevation, (STEMI would just be one infarcted area)
X ray (maybe cardiomegaly), echocardiogram
Bloods: troponin, FBC (slight increase in white count), high ESR indicative of autoimmune, U+Es (uraemia cause)
How is pericarditis treated
Aspirin / ibuprofen high dose (+ PPI), colchicine (for 3m to stop recurrence), exercise restriction
In more extreme cases oral corticosteroids or pericardiectomy might be appropriate
Treat cause; if purulent: IV abx (tailored to blood cultures), steroids for autoimmune
Tamponade - pericardiocentesis, also for purulent or neoplastic
Describe constrictive pericarditis
Constrictive - becomes inelastic/ fibrous/ calcified and interferes with diastolic filling. Can occur in any types but common in TB and rheumatic heart disease
Ascites, oedema, right heart failure, atrial dilation
Describe the murmurs of valve pathologies
Mitral stenosis: mid diastolic, low pitched rumbling, loud S1, LUB dub durr
(In diastole, slow velocity, stiff valves snap back with enough force. Palpable apex beat)
Mitral regurgitation - pan systolic, high pitched, S3, radiates to axilla
(Flowing wrong direction during systole, high velocity from ventricle, backlog of blood in LA causes S3)
Aortic stenosis (most common): ejection systolic, high pitched, crescendo-decrescendo, slow rising pulse + narrow pulse pressure, burrr dub
(High velocity through small gap, reduced cardiac output + systolic pressure, prolonged LV ejection)
Aortic regurgitation: early diastolic soft murmur, collapsing pulse + wide pulse pressure, Lub tarrr
(Small amount returning after systole, drop in aortic pressure during diastole as blood flows back. Aortic thrill)
Tricuspid regurgitation (similar to mitral): pan systolic, high pitched, split S2, inspiration
(Blood returns to RA during systole - faster velocity, RV empties quicker than LV, increased venous return on inspiration)
Pulmonary stenosis: ejection systolic, harsh, crescendo-decrescendo, ejection click
(High pressure through small hole during systole, click due to stenotic valve leaflets, heard best on inspiration, pulmonary thrill)
How are valve pathologies investigated
Echocardiogram gold standard - size, function, valve structure
Serial echos to monitor
Heart sounds, ECG when hypertrophy
Blood pressure - aortic regurgitation: high systolic, low diastolic
Describe the pathophysiology of infective endocarditis
Infection of endothelium, most commonly the heart valves, bacteria in bloodstream adhere to damaged area, vegetations form (bacteria, platelets, fibrin)
Most common cause: staph aureus; also streptococcus (viridans), enterococcus (faecalis)
Risk factors: IV drug use, structural heart pathology, CKD (dialysis), immunocompromised, past Hx
Structural: valvular / prosthetic disease, congenital, hypertrophic cardiomyopathy, pacemakers
Complications: valve pathology, HF, infective / non infective emboli, glomerulonephritis + renal impairment
How does infective endocarditis present
Presentation: fever, fatigue, night sweats, muscle aches, anorexia
Signs: new / changing murmur, splinter haemorrhages, petechiae, janeway lesions, osler’s nodes, roth spots, splenomegaly, finger clubbing
JL: red macules on palms + soles, ON: tender red nodules on pads of fingers + toes, RS: haemorrhages on retina
How is infective endocarditis investigated, what criteria is used
Blood cultures essential, 3 samples 6h apart from different sites (unless septic). Transoesophageal echo, prosthetic valves - SPECT-CT
Modified Duke criteria: major: persistent positive blood cultures, positive imaging; minor: predisposition, T > 38C, vascular phenomena, immunological phenomena, microbiological phenomena
Diagnosis: 2 major, 1 major + 3 minor, 5 minor
(V: splenic infarction, intracranial haemorrhage, Janeway; I: osler’s, roth spots, glomerulonephritis; M: positive cultures not qualifying as major)
How is infective endocarditis managed
Managed by specialist team, IV broad spectrum Abx, 4w or 6w for prosthetic
Surgery required for HF related to valve pathology, large vegetations / abscesses, not responding to Abx
Describe the types of shock
Hypovolaemia, cardiogenic (not pumping), distributive (sepsis, anaphylaxis, neurogenic), obstructive
Hypovolaemic - secondary to haemorrhagic shock, acute loss of blood, loss of fluid (burns, pancreatitis), extreme vomiting / diarrhoea
Cardiogenic - tamponade, pulmonary embolism, acute MI, fluid overload, myocarditis
Decreased cardiac contractility, decreased cardiac output and blood pressure
Obstructive: physical obstruction of great vessels (tamponade, PE, tension pneumothorax)
Distributive: neurogenic: loss of sympathetic tone in vessels (slow HR, less venous return, less CO); vasoactive: release of massive vasoactive mediators, massive vasodilation
Describe the types of cardiomyopathies
Dilated (LV) most common, contracts poorly, like HF: dyspnoea, fatigue, p oedema, arrhythmias
Genetic, infections (coxsackie B), alcohol abuse (toxic, B1 deficiency, inflammation, hypertension), pregnancy (peripartum CM), SLE, RA
Hypertrophic obstructive: LV hypertrophy, deviated septum blocks outflow, autosomal dominant. Risk of HF, arrhythmias, sudden cardiac death. Non specific symptoms, severe present like HF
Restrictive: stiffening of muscle - impaired systolic filling, HF symptoms
Amyloidosis, sarcoidosis, infiltrative - haemochromatosis, radiation therapy
Arrhythmogenic: muscle replaced with fibrofatty tissue - ventricular arrhythmias and sudden death
Takotsubo: LV dysfunction following severe emotional stress, ‘Broken heart syndrome’, resolves
What are the causes of the different types of anaemia
Micro (synthesis issue): iron deficiency, thalassaemia (globin chains), lead poisoning (haem)
Normo: haemolytic (rhesus / ABO, sickle cell, malaria, transfusion reaction), chronic disease (TB, HIV, CKD, SLE), haemorrhage, cancer
Macrocytic: B12 + folate (DNA), alcohol abuse (liver → B12 + folate), myelodysplastic syndromes
Describe the pathophysiology of sickle cell
Sickle cell - mutation causes abnormal beta chain, insoluble and polymerised when deoxygenated (causes spiral effect with acute chest syndrome). RBCs are more rigid, repeated sickling becomes irreversible, carries oxygen less efficiently and blocks vessels.
Acute chest syndrome: lung damage (sickling and infection) → hypoxia → HbS polymerisation → reduced flow → more lung damage
How do you investigate anaemia
Blood count + film (micro/ normo/ macro)
Reticulocyte count - measure of production (how many young cells)
Serum iron/ ferritin. Direct antiglobulin test for autoimmune. LFT / Bilirubin (increased haemolysis). Sickle cell solubility + Hb separation
How is sickle cell anaemia managed
Sickle cell - hydroxycarbamide (increases foetal haemoglobin), supportive (vaccines, prophylactic penicillin, analgesia), repeat transfusions, stem cell transplant
Acute chest: oxygen, incentive spirometry, analgesia (depending on pain), broad spectrum abx
Describe the different types of leukaemia (age, blood film, specificifiers)
Acute lymphoblastic: 2-4, blasts on blood film (children = B, adults = T)
Acute myeloid: 60s, may have normal WCC, most deadly, auer rods
Chronic myeloid: 60s, 80% have philadelphia chromosome, very high WCC, give imatinib (tyrosine kinase)
Chronic lymphocytic: elderly, most common, lack of apoptosis, smudge cells, often no symptoms
Order by age (acutes before chronic): lymphoblastic, myeloid, lymphocytic (also most to least aggressive)
Specifiers: BAPS - blasts, auer roads, philadelphia chromosone, smudge cells
How are leukaemias treated
Treatment: chemotherapy, radiation, stem transplant, targeted. Staging and overall health considered for treatment type.
Chemo: methotrexate, vincristine, daunorubicin, cytarabine
How are lymphomas classified
Classifications: Hodgkin (Reed-Sternberg cells - characteristic mirror image nuclei) vs Non-Hodgkin (low grade vs high grade, B vs T vs Nk, Burkitt, MALT). Non-H: 80% B cell (diffuse large B most common)
What are the risk factors for lymphomas
Hodgkin’s: Ages 20-25 or 80+, HIV, Epstein-Barr virus, autoimmune conditions, family history
Non-Hodgkin’s: HIV, EBV, H pylori (MALT), Hep B+C, exposure to pesticides / trichloroethylene, family history
How does lymphoma present
Lymphadenopathy, fever, weight loss, night sweats
Fatigue, itching, cough, SOB, abdo pain, recurrent infections
What is the pathophysiology of multiple myeloma
Accumulation of malignant plasma cells leads to progressive bone marrow failure. They produce excess of one type of monoclonal immunoglobulin (M / paraproteins)
Plasma cells stimulate osteoclasts and inhibit osteoblasts - osteoporosis (releases calcium into blood). Immunoglobulins deposit in kidneys and cause dysfunction - proteinuria
Other immunoglobulin levels are decreased resulting in immunoparesis and susceptibility to infections
Plasma viscosity increases due to increased proteins - haemorrhages (stroke, retinal etc)
What is the presentation of multiple myeloma
old CRAB: average age is 70. Calcium elevated, Renal impairment, Anaemia, Bone disease
Recurrent infections due to neutropenia
Bone disease leads to osteolytic lesions, pathological fracture and spinal compression
Unexplained fatigue / weight loss / fever, bone pain, abdo discomfort
How is myeloma investigated
Bloods: calcium, FBC (anaemia), U+Es (raised creatinine + urea, reduced creatinine clearance), peripheral smear (Rouleaux - stacked RBCs), plasma viscosity / ESR in primary care
Bone marrow biopsy most important, clonal plasma cells >10%
Immunoglobulins: serum quantitative immunoglobulins, serum/urine protein electrophoresis + immunofixation (urine = Bence-Jones proteins), light chain assay
Whole body MRI / CT - osteolytic lesions, ‘rain drop’ skull
What is the pathophysiology of primary and secondary polycycthaemia
Primary - polycythaemia vera blood cancer (malignant proliferation of a stem cell leading to excess proliferation of RBCs, white and platelets)
Secondary - hypoxia (altitude, chronic lung disease), inappropriate high erythropoietin secretion (kidney/ liver cancer), congenital heart disease
What are the 3 myeloproliferative disorders and what cells are in excess
Polycythaemia vera - RBCs (also white cells and platelets)
Primary myelofibrosis - dysplastic megakaryocytes (also immature white cells and teapdrop RBCs, pantocytopenia in advanced)
Essential thrombocythaemia - platelets (also increased megakaryocytes)
What gene is linked to myeloproliferative disorders and what treatments are used
Hydroxycarbamide is the chemo of choice, aspirin / clopidogrel and venesection for polycythaemia, JAK2 inhibitor ruxoltinib for primary myelofibrosis
What is the pathophysiology of Von Willebrand’s
Most types dominant, vW factor - promotes platelet adhesion to damaged endothelium and stabilises VIII. Deficiency causes bleeding; majority type 1 (less severe) partial reduction, type 2 abnormal vW, type 3 complete lack (recessive)
How is von Willebrand diagnosed and managed
Prolonged PT and aPTT, vW factor antigen
Desmopressin stimulates release of vWF, tranexamic acid, factor infusions (+ VIII)
What is the pathophsyiology of haemophilia A and B
X-linked recessive (females can be carriers, all males); A - deficiency in factor VIII, B - factor IX
How is haemophilia diagnosed and managed
Prolonged activated partial thromboplastin time (aPTT), factor VIII and IX assay
Give factor concentrates and tranexamic acid (antifibrinolytic)
What is the pathophysiology of antiphospholipid syndrome
AI - antibodies bind to phospholipid-binding proteins (i.e. prothrombin), causing damage and activation and venous / arterial thrombosis (causes endothelial damage and platelet activation). Can occur in isolation or part of another condition - most commonly SLE
How is antiphospholipid syndrome diagnosed and managed
Diagnosis from antibodies: lupus anticoagulant, anticardiolipin, anti-beta2 glycoprotein I
Also thrombocytopenia and prolonged aPTT
Primary thromboprophylaxis - aspirin and enoxaparin (or long term warfarin (INR 2-3))
In pregnancy can cause recurrent miscarriage, pre-eclampsia, placental abruption, pre term, VTE LMWH until 34w
