Flashcards in Cardiovascular disease Deck (27)
2 things that cause inadequate supply to the myocardium
Reduced coronary blood flow
4 IHD syndromes
Acute coronary syndrome
Sudden cardiac death
Chronic ischaemic heart disease
3 types angina
Stable- predictable relationship with exertion, due to fixed obstruction
Unstable- plaque disruption, red flag
Varient/prinzmetal- coronary artery spasm
2 ways a subendocardial MI might occur without any acute coronary occlusion?
1. Stable athromatous occlusion
2. acute hypotensive episode
Main blood marker of cardiac myocyte damage?
Troponins T and I
When is troponin peaked?
12hrs post MI
What else is troponin raised in?
PE, HF, myocarditis
4 other blood markers of cardiac myocyte damage?
Creatinine kinase MB
What is Dressler's syndrome?
Complication of MI- autoimmune pericarditis.
Appearance of heart tissue following MI:
Less than 24 hours
More than 3 weeks
Less than 24 hours normal/dark
1-2 days pale, oedema
3-4 days yellow with haemorrhagic edges (macrophages)
1-3 weeks red/grey, pale, thin, granulation tissue then fibrosis
More than 3 weeks dense fibrous scar
What is chronic ischaemic heart disease?
Atheroma = relative ischaemia and angina. Risk of sudden death, MI, unstable/variant angina
2 most common mutations in familial hypercholesterolaemia
Low density lipoprotein receptor gene
How do heterozygotes with familial hypercholesterolaemia present?
What BP is definted as HTN
What do all primary/essential HTN causes have in common?
Positive sodium balance
How does sodium increase BP?
Increases stroke vol as more water in blood, cardiac output is therefore increased, so vasoconstriction occurs to reduce the blood flow as is above metabolic demand, however this increases SVR so BP (SVRxCO) increases.
4 systems that if diseased might cause secondary HTN?
4 effects of hypertension
Acute hypertensive encephalopathy
What BP is a HTNve crisis?
Symptoms of acute hypertensive encephalopathy
Confusion, vomiting, convulsions, coma, death
Framingham study was on what?
Risk factors for heart disease
angiotensin produced in afferent arterioles of kidney
Renin converts angiotensin to angiotensin I
Angiotensin I to angiotensin II
Ang 2 = vasoconstriction and stimulates adrenals to produce aldosterone
Aldosterone inhibits sodium and water loss to increase blood volume.
What is Conn's syndrome
Excess aldosterone secretion usually due to adrenocortical adenoma
elevated aldosterone, low renin
Potassium loss- muscle weaknessm arrhythmias, parasthaesia, metabolic alkalosis
What is phaeochromocytoma
Tumour of adrenal medulla, secretes vasoconstrictive catecholamines (adrenaline and noradrenaline)
Presents with pallor, headache, sweating, nervousness, HTN
Difference between Cushing's disease and syndrome
Disease= pituitary lesion or neoplasm in adrenals that results in overproduction of glucocorticoids
Syndrome = excess glucocorticoids from any source
What is the action of cortisol?
Sympathetic NS activation
Acts on the kidneys to = HTN