Disease Flashcards
Angina Pectoralis
Myocardial workload increases using all ATP, supply of blood and O2 falls. Switches to anaerobic metabolism that creates increased cell permeability- releasing histamine:kinin/enzymes that stimulate pain.
If blood flow not restored within 20mins then progress to MI
Chest pain from reduced coronary blood flow, temporary imbalance between supply and demand. Ischaemia caused by coronary artery spasm , partial obstruction, thrombus
O2 demand increased by exercise, thyrotoxicosis, stimulants, hyperthyroidism, emotional stress, anaemia, heart failure, ventricular hypertrophy, pulmonary disease
Three types
Stable- caused by predictable increase in work of heart (exercise)
Prinzmetal- atypical that is unpredictable often at night, caused by artery spasm
Unstable- increased frequency, severity and duration, pain unpredictable and occurs with decreased level of activity
Treat- GTN, beta blockers, calcium Channel blockers, aspirin
Atherosclerosis
Plaque formation that affects intimacy and medial layers of large and midsized arteries. Lipoproteins and fibrous tissue accumulate in arterial wall.
Attracts platelets and lipoproteins to bind to extra cellular portion of the vessel, stimulating proliferation of the vessel wall and restricts ability of vessel to dilate.
Fibrous tissue can rupture causing thrombus
Myocardial Ischemia
Type of acute coronary syndrome-Myocardial cells become ischaemic when oxygen supply is inadequate to meet metabolic demands
Can be STEMI, or NSTEMI or unstable angina
Causes-
T1- atherothrombic coronary artery disease usually precipitated by atherosclerotic plaque
T2- oxygen supply and demand mismatch (coronary dissection, emboli, vasospasm, microvascular dysfunction
T3- typical MI symptoms but death occurs before blood bio markers (troponin) can be taken
T4a- associated with percutaneous coronary intervention. Must have elevated troponin and evidence of myocardial Ischaemia
T4b- due to stent thrombosis
T5- CABG associated MI
S&S- chest pain radiating to left arm or jaw, SOB, diaphoretic, weakness, anxiety
Women, elderly and diabetics may present like reflux, dyspnoea, nausea and vomiting, palpitations, syncope
Check- heart and lungs, BP on both arms, ECG, pulses on all limbs, bloods,
Electrical disturbances
Damage to heart tissue Anaemia Exercise HT Smoking Fever Medication Hyperthyroidism
Murmur
Diastolic (between S2&S1)
systolic (between S1&S2)
Over aortic, pulmonary, tricuspid or mitral valve
Midsystolic-aortic stenosis, pulmonary stenosis, atrial septal defect, semilunar valve disease/ hypertrophic cardiomyopathy
Holosystolic- mitral valve regurgitation, tricuspid valve regurgitation, VSD
Panstolic- AV valve disease
Late Systolic- MItral valve prolapse
Early diastolic- aortic regurgitation, pulmonary regurgitation, Austin flint
Mid/late diastolic- mitral stenosis, tricuspid stenosis
pre-systolic- mitral stenosis
Continuous- PDA
Systolic heart failure
Ventricle fails to contract adequately to eject blood
Ischaemia, infarction, cardiomyopathy, inflammation
Diastolic heart failure
Heart can’t completely relax in diastole, disrupts normal filling
Hypertrophic and cellular changes
Left sided heart failure
Increased pressure in atria/ventricle causes pulmonary congestion/decreased CO
S&S -Dizziness, syncope, dyspnoea, cough, orthopnoea, cyanosis, inspiration crackles and wheeze, S3 gallop, decreased exercise tolerance (due to increased CO and hearts reduced ability to cope with increase in blood returning to heart, afterload and tachycardia)
Right sided heart failure
Causes acute- pulmonary emboli, right ventricle MI, myocarditis, cardiac tamponade, LVAD insertion (heart not used to increased venous return to right atria and septal bowing from left ventricle remains), superior or inferior vena cava obstruction, pulmonary hypertension, ARDS, chronic lung disease
Causes chronic- myocarditis, cardiomyopathy, chronic thromboembolic pulmonary hypertension, congenital heart disease
Increased pulmonary pressure or right ventricle/atrial/tricuspid damage or impaired vena cava flow impair blood pumped to pulmonary system and can’t per fuse the lungs. Blood accumulated in systemic venous system and causes abdominal organs to congest and peripheral tissue oedema
S&S -Anorexia, nausea (GI congestion), RUQ pain due to liver enlargement, neck vein distention, dyspnoea,
Management- maintain O2 delivery to tissues (supplimental O2), monitor volume status- sodium and fluid restriction, daily wt, arrhythmia support, activity restriction, advanced therapies for refractory HF, palliative care, diuretics
Low output failure
Cardiomyopathy, CHD, HT
High output failure
Increased blood flow can’t meet O2 requirements, compensation mechanisms increase CO which increases O2 requirement that can’t be met
Cardiogenic pulmonary oedema
Causes-systolic dysfunction, diastolic dysfunction, mitral stenosis, renovascular hypertension
Left ventricle failure causes pulmonary hydrostatic pressure to rise, fluid leaks from pulmonary capillaries into interstitial tissues decreasing lung compliance and gas exchange.
As pressure increases junctions of alveoli walls are disrupted and fluid (RBC and protein molecules)enters alveoli
Treat= Morphine- anxiety and vasodilator
O2 via positive pressure
Loop diureticGTN- vasodilation
Rheumatic fever/RHD
Abnormal immune response to pharyngeal infection by group A beta haemolytic streptococci
Antigens bind to cells in heart, brain, muscle and synovial joints creating immune response. Inflammatory lesions develop on heart,joints and skin.
Can lead to carditis in myocardium, pericardium or endocardium.
Endocarditis affects valves and leaves fibrous scarring causing deformities.
Repeated attacks cause stenosis and regurgitation of valves- mostly mitral
Infective endocarditis
Inflammation of endocardium- lesions on deformed valves and tissue damages sites. Usually left side and mitral valve, IV drug users affects right side and tricuspid
Lesions create platelet/fibrin that cause bacteria to colonise, enlarge then covered by more platelets which protects bacteria from immune system defences
Scar tissue obstructs blood flow
Treat- antibiotics/ surgery
Myocarditis
Inflammation of heart muscle
Myocardial cells damaged in inflammatory response cause local swelling, infectious agents infiltrate interstitial tissue forming abscess
Treat- antibiotics, antiviral immunosuppressants, bed rest, activity restriction
Pericarditis
Inflammation caused by infectious agent or non-infectious agent (myocardial injury, uraemia, neoplasms, radiation, trauma, surgery, myxoedema, autoimmune disorders, rheumatic fever, connective tissue disease, drugs, .
Damage creates inflammatory response, mediators released cause vasodilation, hyperaemia, oedema, capillary permeability Increases allowing plasma to escape into pericardial space. WBC destroy causative factor which turns into exudate and scarring restricts cardiac function.
Complications- pericardial effusion, cardiac tamponade, chronic constrictive pericarditis
Treat- aspirin, NSAIDs, pericardiocentesis, surgery
Stenosis
Valve narrow impeding forward blood flow, atria enlarge, reduced CO and high pressures into ventricles can damage ventricles ( risk endocarditis), increases myocardial O2 requirement, workload exceeds O2, Ischaemia, chest pain
High pressures push backward and cause pulmonary oedema, pulmonary HT, ventricle failure
Mitral stenosis
Narrowing of mitral valve, obstructs blood flow in left atria.
Caused by RHD or bacterial endocarditis
Complications- atrial arrhythmia (AF), thrombi
Mitral regurgitation
Blood flows back into atria during systole, left atrium dilates to accomodate increased blood, pulling valve more open making it worse. Left ventricle dilates to accomodate increased preload and low CO
Mitral prolapse
One or more aerial valve cusps billow I to atrium during systole
Associated with marfans/ connective tissue disorders
Complications - bacterial endocarditis, heart failure, thrombi
Aortic stenosis
Obstructs blood flow from left ventricle to aorta during systole
Can be idiopathic/congenital/RHD/ degenerative
Valve decreases in size, increasing workload of left ventricle to eject blood through narrowing, ventricle hypertrophies and compliance decreases. Increased myocardial workload and O2 consumption cause myocardial Ischaemia.
Left ventricle pressure increases causing increased left atrium pressure and pulmonary oedema.
Aortic regurgitation
Allows blood to backflow into left ventricle.
Caused by RHD, congenital, infective endocarditis, chest trauma, aortic aneurysms, syphilis, marfans, chronic HT.
Impedes complete valve closure and adds blood volume to left ventricle. Increased left ventricle pressure, increases preload causing more forceful contractions and high SV. Muscle cells hypertrophy to compensate-compromises CO and increases regurgitation.
High left ventricle pressure causes high left atrial pressure leading to pulmonary congestion and eventually right heart failure
Tricuspid stenosis
Obstructs blood from right atrium to ventricle. Increase in atrial pressure enlarges atrium, ventricle SV decreases, reducing volume going to pulmonary system and left heart causing reduction in SV, tissue perfusion and CO
Usually from RHD
Tricuspid regurgitation
Stretching distorts valve, prevents closure. Right atrium enlarges causing systemic venous congestion and low CO, atrial fibrillation
Caused by left ventricle failure/pulmonary HT leading to right atrial overload