Cardiac Emergencies

syndromes affecting the heart as a result of plaque rupture in the coronary arteries

imbalance between myocardial O2 supply and demand Accumulation of lactic acid and CO2 in ischaemic tissues of myocardium - metabolites irritate nerve endings and produce pain

usually precipitated by physical exertion or emotional stress typically lasts 1-5 mins relieved by GTN and or O2 attacks are usually similar in nature and relieved by same therapy

pattern that has changed in onset, frequency, intensity, duration or quality may occur during exercise or at rest pain lasts greater than 10 mins and is less promptly relieved indicitive of changes in degree of oclusion of coronary arteries

total or near occlusion of blood flowing through a coronary artery Ischaemia, injury and necrosis of myocardium distal to occlusion Often associated with atherosclerotic heart disease

metabolic needs of tissue supplied by occluded vessel collateral circulation time until flow is re-established

GTN has haemodynamic effecs such as dilation of venous capacitance vessels, dilation of coronary arteries and to a minor extent, peripheral arteries

calming effect a dilator of venous capacitance vessels

develops when plasma volume increases and fluid accumulates in the lungs, abdo aorgans and peripheral tissues

left ventricle fails to function as an effective forward pump causes back pressure of blood intu pulmonary circulation

ischaemic heart disease valvular disorders hypertensive heart disease

resp distress apprehension, agitation, confusion cyanosis diaphrosesis adventitious lung sounds jugular vein distension abnormal VSS

R ventricles fail as a forward pump causing back pressure of blood into systemic venous circulation

chronic hypertension pulmonary embolism valvular heart disease RV infarction

tachycardia venous congestion - venous distension and peripheral oedema fluid accumulation in serous cavities

most extreme form of pump failure LF function is compromised and heart cannot meet metabolic needs of body

when blood or fluid escapes into the pericardial space can be: transudative - congestive heart failure, exudative - tuberculosis, haemorrhagic - trauma, malignant - cancer

chest pain duspnoea hypotension distant heart sounds

a radiographic sign of pericardial effusion

dullness to percussion over the left subscapular area due to compression of left lung base

increased fluid in pericardial space impairs diastolic filling of heart ventricular filing is mechanically limited and SV decreases

inflammation of pericardium

trauma infection MI malignant neoplastic disease ureaemia idiopathic causes

a tear in the intimal layer of a vessel wall resulting in separation into 2 layers