8. Anti-anginal Agents Flashcards
1
Q
- what is myocardial ischemia?
- how is this experienced by patients?
- what are 3 strategies to relieve anginal pain?
A
- Imbalance between O2 supply and consumption
- painful, chest crushing sensation
- ↓ in physical activity, Cardiac revascularization surgery, Drug therapy
2
Q
- what are the 3 unique features of the myocardium?
- what does the relationship between blood flow and oxygen lead to? (hint: 2)
- what are 3 factors that can contribute to tissue ischemia?
A
- Cannot accumulate O2 debt, Significant and relatively constant O2 needs, Inverse relationship between blood flow and O2 delivery
- Blood flow ↓ as HR and workload ↑ and Extracts most of the available oxygen
- Intolerance of metabolic wastes, ↑ O2 demand, ↓ blood flow at elevated HR
3
Q
- what does “striking a balance” refer to?
- what is the equation for this?
- what is relatively constant? at what pressure? what is near maximal?
- what 3 factors affect myocardial O2 consumption?
A
- O2 uptake/consumption in the tissues
- MVO2 = CBF (coronary blood flow) x (CaO2 – CvO2)
- O2 delivery @ 100 mmHg, myocardial extraction
- ↑ contractility (SV), ↑ HR, Ventricular wall stress
4
Q
- what is angina pectoris?
2. what are the 3 types of angina?
A
- “choking of the chest” (tightness in the chest)
2. Classic, Variant, Unstable
5
Q
- exertional angina is classified as what type of angina?
- what is exertional angina? what does this lead to? what does this type of angina respond well to
- what is this type of angina caused by? what is this condition defined as?
- what is the problem with plaques associated with this condition?
A
- classic
- inadequate O2 delivery with physiologic stress (e.g., exercise, emotional stress) leading to intense chest pain that responds well to nitrates
- Caused by atherosclerosis/arteriosclerotic vascular disease which is thickening of the arterial wall
- Plagues significantly ↓ BF in affected vessels
6
Q
- what is atherosclerosis characterized by? what can this lead to?
- what are plaques primarily made of?
A
- elevated LDL and cholesterol, low HDL leading to plaque formation
- Fatty deposits, Cholesterol, Calcium
7
Q
- what is variant angina also known as?
- this type of angina causes ____ _____ _____
- what are the 4 distinguishing characteristics of this type of angina?
- decreased CBF is related to ______ ______ ______
- not triggered by _____ _____ ______
- this type of angina can also be referred to as?
- this type of angina responds well to what medication?
A
- Prinzmetal’s angina
- significant chest pain
- Prolonged attacks, Cyclical occurrence, Not effort dependent, Can lead to infarction and sudden death
- coronary artery system
- increased O2 demands
- Angiospastic/vasospastic angina
- calcium channel-blockers
8
Q
Acute coronary syndrome is defined as? what are the 3 states involved?
A
Collection of 3 cardiac disease states classified according to ECG:
- ST elevation myocardial infarction (STEMI)
- NSTEMI
- Unstable angina
9
Q
- unstable angina is defined as? what pattern is this associated with? what does this pattern mean?
- what is NOT seen on the ECG?
- what 2 problems is this type of angina associated with?
- what 3 medications does this angina respond well to?
- what are the 5 contributing endothelial factors?
A
- Prolonged anginal symptoms at rest; crescendo pattern –> Changing intensity, duration or frequency
- No ST elevation seen on ECG
- Coronary artery spasm and ↑ O2 demand
- Responsive to nitrates, b-blockers and calcium channel-blockers
- Tearing of plaque, Platelet aggregation, Thrombosis, Embolization, Vasospasm
10
Q
- plaque can shear away from ____ _____. what can this lead to?
- what can the resultant ischemia progress to? this can happen if what is not restored?
- what are the two options for resolving a blockage?
A
- vessel wall. Leading to an embolus that travels downstream creating occlusion
- acute infarct if perfusion is not restored quickly
- removed or bypassed
11
Q
- what are the 2 goals of drug therapy?
2. what are the 3 anti-anginal drug classifications?
A
- ↑ O2 supply to the myocardium by improving coronary blood flow AND Reducing tissue O2 demands by ↓ workload on the heart
- Nitrates, Calcium channel-blockers and Beta-blockers
12
Q
- nitroglycerin is what type of vasodilator? introduced in what year?
- what can this drug help decrease? (hint: 2)
- what are the 5 ways this drug can be administered?
- what is the onset for short acting nitroglycerin? duration?
- how long is the duration for long acting nitroglycerin?
A
- prototype vasodilator introduced in 1879
- Decreasing preload and afterload
- Oral, Buccal, Sublingual, Transcutaneous, IV
- 1-3 min onset, 10-30 min duration
- Long-acting 6-8 hr duration
13
Q
- what cells do nitroglycerin act on? what does this induce?
- describe the 5 phases of how nitroglycerin behaves in the body.
- where are the effects of this drug more pronounced? causing a decrease in what? this will result in what?
- can nitrates be used to treat all forms of angina?
A
- Acts on smooth muscle cells to induce relaxation of arteries and veins
- Nitrates –> Nitric oxide –> ↑ cGMP –> ↓ Ca2+ –> vasodilation
- Effects more pronounced on venous side causing a ↓ venous return & preload resulting in ↓ ventricular wall stress & O2 demands
- yes!
14
Q
- how are nitrates helpful in treating classic angina? (hint: 2)
- how are nitrates helpful in treating variant angina? (hint: 1)
- how are nitrates helpful in treating unstable angina? (hint: 2)
- what else can nitrates be helpful in treating (non-anginal)? when treating this what are nitrates also administered with?
A
- ↓ ventricular wall stress and ↓ O2 demands
- ↓ angiospasm
- improved O2 delivery and ↓ O2 demands
- administration with cardiotonics to treat CHF
15
Q
- what are the 3 contraindications to using nitroglycerin?
- what are the 3 precautions to using nitroglycerin?
- what are the 4 adverse reactions when using nitroglycerin?
- other nitrates available are available with the same ______ ____ ______.
- available in a ______ of formulations, both ____ and _____ ______.
- what are the other 2 nitrates available?
A
- Shock, Hypovolemia, Hypotension
- Reflex tachycardia that ↑ O2 demands, Erectile dysfunction meds, Tolerance
- ↑ HR, Orthostatic hypotension, Migraine-like headaches, “blushing” above the clavicles
- mechanism of action
- different, short and long acting
- Isosorbide dinitrate (Isordil ®) and Isosorbide mononitrate