Ischemia/Angina Flashcards
Ischemia
Mismatch between myocardial oxygen supply and demand
Most common cause of myocardial ischemia
Atherosclerosis
Nocturnal Angina
Manifests after lying down in pats with HF d/t increase in venous return
Postprandial Engina
Develops soon after eating due to increased oxygen demand of splanchnic vascular bed
Silent Ischemia
No or minimal symptoms can be evoked despite objective documentation of myocardial ischemia
Ways to relieve angina
Decrease demand or increase supply
If caused by plaque—>you can vasodilate all you want but it will be more difficult to get O2 to heart. Easier to work on demand side
Stable Angina
Symptoms have not changed and are precipitated by increased effort.
Predictable
Relieved by rest
Generally a stable clot
Unstable Angina
Occurs at rest and is not predictable. Not relieved with rest.
Generally a large unstable/ruptured plaque and spasm
Largest predictor of Perioperative ischemia
Tachycardia
Drug therapy for angina
Nitrates: first line therapy to decrease oxygen demand via reduction in preload
BB: decrease cardiac demand via lower HR/BP/Contractility
CCB: decrease demand, increase supply. Good in asthmatics (no bronchoconstriction), variant angina
Aspirin/Clopidogrel
Statins
ACE-I
Ranolazine: blocks late inward Na current reducing intracellular Ca overload
N-STEMI (ST depression instead of elevation)
Subendocardial ischemia with abnormal repolarization (partial thickness)
STEMI with Q wave b
Full thickness injury (transmural)
Stunning
Follows chest pain from effort angina.
Slow recovery of full cardiac function may last 3-4 hours depending on how severe attack was
How CCB and BB prevent angina
Cardiac depression prevents angina. Decrease myocardial oxygen demand
Reduce afterload
How Nitrates and CCB reduce angina
Reduce preload, reduce venous return (Vasodilation)
