Pathology of Coronary Artery Disease Flashcards
What is the most common cause of coronary artery disease?
Atherosclerosis
How long after an MI would you expect to find a neutrophilic infiltrate on histological analysis?
1-3 days
What finding on an ECG may indicated an NSTEMI?
ST segment depression
What three pathologies are considered Acute Coronary Syndrome?
Angina pectoris, myocardial infarction, sudden cardiac death
What type of angina is associated with ST segment elevation that mimics an acute MI?
Prinzmetal angina
What type of MI is causes by a transmural infarct.
STEMI - a subendocardial infarct causes an NSTEMI
Following ischemia, what region of myocardium is most susceptible to damage?
Subendocardium - this region is supplied by the distal coronary arteries.
What is the most common cause of sudden cardiac death in young athletes?
Hypertrophic cardiomyopathy
A patient is told they have a heart murmur following an MI 6 days ago. What is the cause?
Rupture of the papillary muscle - likely posterior leaflet
True/False. An acute MI may present as heart failure, before permanent myocyte death.
True - this is because contractility ceases within a minute of ischemia
What is the most common cause of death in the first 24 hours following an MI?
Arrhythmias
What is the cause of prinzmetal angina?
Coronary artery spasm that is unrelated to activity
Mitral regurgitation is common with a myocardial infarct of right coronary artery. Why is this?
The RCA supplies the posterior papillary muscle, which ruptures without blood supply
What illicit drug is most associated with sudden cardiac death?
Cocaine - causes coronary artery vasospasm
A patient presents to the ED with an acute MI that began 1 hour before. Unfortunately, the patient expires shortly after arrival. What histologic changes would you expect to see?
None - there are no gross or histologic changes in the first 3 hours following an MI
True/False. Women are at higher risk for acute MI than men.
False - women are protected by estrogens and at lesser risk of MI. This protection dissipates with menopause.
A patient had a confirmed MI 5 days ago. They now have new onset angina. Cardiac enzymes are tested and reveal elevated troponin, with normal CK-MB. Is this a new infarct?
No - troponin remains elevated for up to 10 days following an infarct. CK-MB is elevated up to 3 days
Stable angina presents with pain upon exertion that is relieved with rest. How much of the vessel lumen is obstructured?
Greater than 70%, but less than 90%
What histologic changes occur within 3-24 hours following a myocardial infarct?
Wavy fibers with edema, contraction band necrosis, neutrophils
What is Dressler Syndrome?
Fibrinous myocarditis caused 2-3 weeks post-MI, often due to an autoimmune reaction
True/False. Unstable angina indicates a myocardial infaraction is imminent/
True - the patient must be monitored and treated. Vessel occlusion is greater than 90%, but less than 100% (MI)
What cardiac enzymes will be present 12 hours following an infarct.
Troponin & CK-MB
A patient experienced an MI 5 days ago. Upon examination today, heart sounds are muffled. What is the likely cause?
Ventricular rupture
True/False. Myocytes dies within a minute of ischemia.
False - contractility ceases within a minute of ischemia. Myocytes take 20-30 mins to die wihout O2 supply
What population is most commonly affected by prinzmetal angina?
Women 20-30yrs
A patient had an MI 5 days ago. What cells predominate on histological analysis?
Macrophages - days 3-10
A transmural infarct causes a STEMI. What ECG finding is permanent following a transmural MI?
Exaggerated Q wave
What is a circumferential subendocardial infarct?
Global hypoperfusion of the heart caused by hypovolemia or hypotension in a patient with atherosclerosis of the coronary arteries
What is the most common cause of right heart failure?
Left heart failure
What is Cor Pulmonale?
Right heart failure caused by a primary lung problem (COPD, emphysema, pulmonary hypertension, etc.)
How long does it take for an myocardial infarct to become transmural?
Approximately 6 hours
What coronary artery is most often blocked with a posterior papillary muscle rupture?
Right coronary artery
A patient experiences a myocardial rupture following an acute MI. What type of MI did they have?
Transmural infarct (STEMI)
