NSTEMI Flashcards
Definition
Caused by partial occlusion
NSTE - ECG changes
MI - signs and symptoms, blood tests, angiography
Pathway 2 (NSTE-MI)
No ST elevation but other ST segment or T wave changes and chest pain and/or history and symptoms consistent with AMI
LBBB without clear history/symptoms of AMI
No ECG changes but current cardiac chest pain
ST segment elevation but symptoms resolve with GTN
Pain free patient with ECG changes and chest pain in last 24 hours
Stable angina
Narrowed and atherosclerosis effected coronary arteries have reduced blood flow which causes pain on exertion
unstable angina
Partial occlusion due to ruptured plaque and thrombus formation causing constant pain
Factors effecting ECG
Amount of myocardial damage
Duration and severity of ischaemia
Electrical instability of specific myocardial area
Rate of development of obstruction
Presence of collateral coronary circulation
ST depression
Represents subendocardial ischaemia with no infarction
seen typically in
T wave inversion
abnormal T waves are symmetrical
T wave inversion is negative waves in normally positive leads (1,2, V3-6)
or positive T waves in aVR.
Wellens syndrome
characterised by deeply inverted T waves or biphasic T waves in V2-3
highly specific for critical stenosis of the left anterior descending artery
Pathological Q wave definitions
over 40ms long
over 2mm deep
over 25% of QRS depth
any Q wave seen in V1-V3
Pathological Q wave formation
Window effect caused by akinesis of cells in ventricular wall meaning view is of septal wall instead which has electrical activity in the opposite direction. Seen only in NSTEMI as presents infarction not ischaemia.
