ECG of Ischemia, MI, and Hypertrophy Flashcards
location of nonSTEMI ischemia
ischemia is usually endocardial
location of STEMI ischemia
ischemia is usually transmural
best method of treatment for STEMIs
opening the blocked artery as soon as possible with angioplasty or thrombolysis
stages of STEMI
hyperacute phase
acute phase
old myocardial infarction
hyperacute phase of STEMI
characterized by the presence of tall, peaked, hyperacute T-waves, with or without ST elevation
occurs minutes after the acute occlusion of the coronary artery and can last up to a few hours
often gone by the time the patient arrives at the emergency department
acute phase STEMI
characterized by elevated ST segments >/= 1 small box
hyperacute T-waves resolve
q-waves may start to appear
can appear within minutes after coronary occlusion but more typically appears in a few hours and lasts up to a few days
after hours or days, T waves begin to invert and ST segments begin returning to baseline
key features of an old MI
Q waves are the hallmark of myocardial scarring typically seen in old and large MIs
duration of Q waves are great than or equal to 0.03 sec or 0.02 sec in V2 or V3
amplitude of Q waves are greater than or equal to 0.1 mV
Q-waves whould be present in 2 contiguous leads
Where is electrical activity in the anterior wall of the LV best seen?
leads V1 - V4
Where is electrical activity in the inferior wall of the LV best seen?
leads I, aVL, V4 - V6
Where is electrical activity in the inferior wall of the LV best seen?
leads II, III, and aVF
ECG findings of nonSTEMI
ST depression, persistent T wave changes, or nothing
diagnosed using enzyme levels in the blood
other causes of ST and T-wave changes other than STEMI
normal variation
ventricular aneurysm
pericarditis
normal variation of ST and T wave
early repolarization of J-point elevation
seen in young people
ST segment electated in multiple leads
St segment usually concave from above
ventricular aneurysm
persistent ST elevation after an MI
pericarditis
St segment is usually elevated in multiple leads
associated with clinical picture
sometimes associated with PR depression
sequential ECG changes differs from those of MI
