Ischemic Heart Disease Flashcards
Ischemic Heart Disease Definition
narrowing of one or more coronary arteries due to atherosclerosis
Ischemic heart disease names
Coronary artery disease (CAD); coronary heart disease (CHD), Atherosclerotic cardiovascular disease (ASCVD)
What is the most known outcome of ischemic heart disease?
Heart attack (or myocardial infarction)
What is the leading cause of premature mortality and hospitalization?
Ischemic Heart Disease
2nd leading cause of death after cancer
Leading cause of hopsitilization
What are the main types of cardiovascular disease?
Ischemic heart disease (IHD)
Cerebrovascular disease (CVD)
Peripheral arterial disease (PAD)
Venous thromboembolic disease (VTE)
Heart failure
Arrhythmia
What diseases are due to artherosclerosis?
Ischemic heart disease (IHD)
Cerebrovascular disease (CVD)
Peripheral arterial disease (PAD)
The major cause of myocardial infarction is….
Artherosclerosis in coronary artery –> Coronary artery disease
One cause of cerebrovascular Accident (CVA) or stroke is….
Artherosclerosis in cerebral arteries –> Cerebrovascular disease
Peripheral Arterial Disease (PAD) is due to….. and can cause…
Artherosclerosis in arteries of the limb and can cause poor circulation, pain, numbness, etc.
A heart attack is a result of conditions that have been present for…
Many Years
Symptoms of Coronary artherosclerosis can present as….
Silent (asymptomatic) disease –> most patients!!
Chronic, stable (exertional) angina
Acute coronary syndromes (ACS)
Acute Coronary Syndrome includes…..
Unstable angina, NSTEMI, STEMI
Angina Sx
Dull, retrosternal discomfort/ache/heaviness
May or may not radiate to jaw, neck, shoulders, arms
What are the two types of angina? What are they a result of?
Stable angina is a problem of “demand exceeding supply”
Unstable angina is a result of inadequate “supply regardless of demand
Fixed Obstruction Angina (stable angina) is defined as…
An increase in demand that cannot be accommodated with increased supply.
“Demand” for oxygen increases when cardiac myocytes increase energy expenditure
Is stable angina pain associated with plaque rupture?
NO
What happens if we increase pre-load?
Increase workload
An increase in demand means an increase in these body functions…
Heart rate (HR)
Venous return
Blood pressure (BP)
Contractility
(exertion, emotion, mental stress)
What are some triggers of stable angina?
SNS activity: Physical exertion, Emotion, Mental stress
Exertion after a heavy meal (SNS and metabolic demands)
Metabolic demands imposed by:
chills, fever, hyperthyroidism, tachycardia, exposure to cold, and hypoglycemia
Anemia (low oxygen content in blood)
An important factor to consider in unstable angina is….
Rate of increase of myocardial work (quick onset) can be very important
When are coronary arteries supplied with blood?
Diastole
In response to metabolic demnds, small endocardial vessels do wht?
Under normal conditions, small endocardial vessels can constrict or dilate according to metabolic demands
At what % do epicardial vessels need to be obstructed at to be fully dilated? What is the result?
If epicardial vessels are obstructed over 70-75%, endocardial vessels will be fully dilated under resting conditions
Increases in demand will not be accompanied by increased flow –> further dilation is not possible
In fixed obstruction, what other vascular problems may present?
Endothelial dysfunction (↓ N.O. production)
Microvascular dysfunction (poor response to N.O.)
The role of vasospasm
What is the role of vasospasm in fixed obstruction angina?
Can be the sole cause of angina (rare! - Prinzmetal’s angina or variant angina)
Can also play a role in patients with ACVD
Stable angina can be relived by….
Rest and Nitroglycerin
Nitrates cause….
Vasodilation
All nitrates are….
Pro-drugs
Nitrates are converted to….
Nitric Oxide
What is Nitric Oxide? What does it do?
NO is a paracrine hormone synthesized by endothelial cells to signal smooth muscle cells ‘next door’
Relaxes smooth muscle in blood vessel walls (vasodilation)
Do Nitrates drop arterial blood pressure?
NO
Targets veins
How does NTG treat stable angina?
Primary effect is by reducing pre-load. Blood pools in the veins. Reduce workload of the heart.
High pre-load, greater venous return, frank-starling law, increase workload of heart
Pre-load Definition
Preload is the degree to which the myocardium is stretched before it contracts
What is the Frank Starling Law?
The energy (force) of contraction is proportional to the initial length of the cardiac muscle fiber”
An increase preload equals
Increased workload of the heart
Class I Angina
- Ordinary physical activity does not cause angina. Occurs with strenous, rapid or prolonged exertion
Class II Angina
Slight limitation or ordinary activity. Walking, climbing stairs rapidly
Class III ANgina
Marked limitations of ordinary physical activity
Class IV Angina
Inability to carry on physical activity w/t discomfort –> angina sx present at rest
Exercise Stress Testing occurs on
On treadmill or stationary bike
In an exercise stress test, what is the process?
ECG, heart rate and BP monitor
Exercise is initiated slowly and slowly builds
It is stopped if chest pain, ST changes, decrease in BP >/=10mmhg
During an exercise stress test, what is observed on the ECG if cardiac ischemia is occuring?
- Depression of S-T segment
- Angina Pain
S-T Depression is indicative of…
S-T depression is a classic sign of cardiac ischemia
What is a common way to notice stable angina?
S-T Depression
Does S-T depression indicate if myocardial cell death has occured?
Does NOT indicate if myocardial cell death has occurred (i.e., myocardial infarction)
ST depression indicates…
ischemia) – does not tell you if any cardiac myocytes have died
ST elevation indicates…..
Infarction
If the QT interval is delayed, greater the risk for…
Time for ventricular depolarization and repolarization
If process is delayed ↑’s risk for ventricular arrhythmias
Is stable angina a medical emergency?
NO
Cardiac Catheterization and Angiography are used to…..
Commonly performed to evaluate coronary artery blood flow and identify locations of narrowed vessels due to atherosclerosis
What is the Core Medication Therapy for patients with cornary artery disease?
ABCDEK
Antiplatelets
Blood pressure medications (not necessarily for BP)
Cholesterol-lowering medications
K-CKD (CKD often present with CAD so always check!)
Diabetes medications
Exercise/diet/ lifestyle changes (stress, alcohol, tobacco)
Beta-blockers can be used to help prevent…..
Angina
ACE Inhibitors in CAD???
“Consider” in all patients with stable IHD
ACE inhibitors should be used in CAD when…..
Prescribe” in all patients with the following indications:
Ejection fraction < 40% (i.e., LVSD) *one exception- if they take valsartan/saccubitril
Hypertension
Chronic kidney dz
if a patient has an intolerance to an ACE, what drug can be used?
ARB’s
In regards to angina, goals of tx should include?
goals of therapy must include BOTH symptom relief AND protection against disease progression and disease outcomes
Anti-angina therapy alternatives include….
The following drugs have an indication to prevent or reduce the frequency/intensity of stable angina episodes
Beta-blockers
DHP CCBs
Non-DHP CCBs
Nitrates
Ranolazine (CorzynaTM) (secondary therapy)
Are beta-blockers useful in angina? Why?
Prevents angina through↓ demand
When are beta-blockers used first line in stable-angina?
Should be used first-line for stable angina in people with another indication for BB:
Post MI (indication for BB)
Systolic HF (indication for BB)
Typically used first-line for other patients due to evidence in conditions above.
Beta-Blockers Dose in Stable Angina?
Dose titrated to a resting HR of 55 to 60 bpm
What beta-blockers should be used to prevent angina? Which are preferred? Why?
All BB are effective equally to prevent angina
B1 selective agents preferred due to lower risk of:
Erectile dysfunction (B2-blockade)
Peripheral circulation problems (esp pts with PAD)
Interaction with B-2 agonists (i.e., Ventolin)
Which Beta-blockers should be avoided?
Avoid BB with ISA (e.g., acebutolol)
Beta Blockers should be monitored for…..
↓Heart Rate and BP AV block or low HR
Signs of poor cardiac output Exercise tolerance or ↓ Renal perfusion (RAAS / edema etc)
Reduced circulation Caution in Raynaud’s / PAD (esp B2)
Respiratory disease (Asthma) generally safe
Diabetes Can mask hypoglycemia; Blood sugar ↑?
Non-slective beta and alpha blockers examples. BP Effect, useful in stable angina?
Carvedilol (Coreg) and Labetalol (Trandate)
Non-selective (B1 and B2 inhibition) AND
Alpha1-receptor inhibition (vasodilatory effect)
Greater fall in BP expected compared to other beta-blockers
Not typically used for stable angina (unless complications exist)
Non-DHP CCB’s Examples
Diltiazem and Verapamil
No DVD’s
Non-DHP CCB’s tx effect compared to BB’s
Same therapeutic effect as BBs - Main difference is intensity of action (reducing cardiac workload, peak HR does not get as high, prevent heart attack)
Non-DHP CCB Adverse Effect
Constipation can occur in 1/10 patients
Non-DHP CCB’s inhibit….
Inhibits 3A4 (also a substrate)
Avoid Non-DHP CCB’s in….
systolic dysfunction (low EF/systolic HF) Can increase the risk of HF exacerbation (One key difference between BB and Non-DHP CCBs)
Already using BB (not an ideal combination)
Bradycardia or AV block
Heart Block/AV Block is diagnosed by….
AN ECG
1st Degree AV Block ECG
-P-R interval Delay –> Time from atrial contraction to ventricular contraction is delayed
2nd Degree AV Block
Intermittently dropped QRS
3rd Degree AV Block
P and QRS are independent
What types of AV Block are C.I. to beta-blockers and/or Non-DHP CCB?
2nd or 3rd degree AV block is a contraindication to beta-blockers and/or non-DHP Calcium channel blockers
**UNLESS a ventricular pacemaker is present
What can occur in a pt from Non-DHP CCB’s and/or BB’s?
Bradycardia or first degree heart block can occur from Non-DHP CCB or BB
DHP CCB’s for stable angina?
Vasodilator
Good tolerability
BB and DHP CCB’s Interaction with each Other
Can be safely combined with BB if symptoms persist (notwithstanding BP lowering effects)
DHP CCB’s over BB’s are a good alternative for…
Good alternative as monotherapy for patients with bradycardia or intolerance to BB
Nitrates can be used….
Can be used as:
treatment (prn use – spray/s/l tablets) or prevention (typically with NTG patch*)
Nitrate-free interval required to maintain efficacy
Why is a nitrate-free interval required?
Tolerance is possible - Varies from patient to patient (not predictable)
Nitrate-free interval of 10-14 hours every day appears to prevent tolerance from occurring
How long does it take for NTG to work? When should it be taken?
PRN NTG can be used BEFORE activities that are known to cause angina (take 2-5 min before – should last 30 min)
S/e of NTG
Headache most common s/e – quite common. Tolerance to headache usually occurs within 2 weeks (acetaminophen may be used)
Low blood pressure/orth hypotension possible but not common
Patches may cause skin irritation, redness, etc. Rotate site every day.
C.I. of Nitrates
PDE5 inhibitors 24hrs for sildenafil/vardenafil; 48hrs for tadalafil)
Caution with BP lowering drugs
Combo Options to consider for help if angina pain persists
Metoprolol + NTG patch
Metoprolol + Amlodipine
Increase Metoprolol dose (Reasonable approach not like HTN)
Switch metoprolol to monotherapy of another agent
Ranolazine…. Add on
BB + NTG
BB + DHP-CCB
Increase BB
If blood pressure is low, DOC
Nitro
If blood pressure is high, DOC
Amlodipine
Ranozoline Indication, MOA, impact on BP or HR
Not used commonly - Indicated as “add-on therapy” for people inadequately controlled or intolerant of first-line agents
Inhibits the late sodium current (INa)
Leads to Ca in cardiac cell and possibly lower diastolic tone
No impact on BP or HR
Ranazoline should be used in caution with (drugs/conditions)….
Cautions: 3A4 inhibitors, QT prolongation, renal dysfunction, others
What are the common options to treat coronary artherosclerosis?
Medical therapy
Continue with drugs
Revascularization
What are the types of revascularization?
Coronary artery bypass grafting (CABG)
Percutaneous Coronary Intervention (angioplasty/stent implantation)
Fibrinolytic medications (only for acute emergencies such as myocardial infarction – used much less frequently currently)
CABG
Invasive Requires open heart surgery
PCI is
percutaneous coronary intervention
What is the most common tx for stable angina? What does it treat?
PCI
Very effective Increasing supply Will cure the angina but not the the coronary artery disease
DAPT stands for and is….
Dual Antiplatelet Therapy
Refers to the use of ASA + a P2Y12 inhibitor (ADP inhibitor)
What is the difference between BMS and DES?
Originally, only bare metal stents were used (BMS)
Stents often elute drug now (Drug Eluting Stents - DES)
Drug coating (in DES) is usually an immunosuppresant to ↓ inflammatory cytokines and cell proliferation following stent implantation
What is thr risks associated with longer and shorter DAPT durations?
Longer DAPT = ↑ risk of bleeding
Shorter DAPT = ↑ risk of events
How long do people often get DAPT for?
1 Year
In the setting of SIHD (stable ischemic heart disease) DAPT ise recommended….
In the setting of SIHD, DAPT is recommended after PCI
All DAPT evidence is based on….
clopidogrel + ASA
Monitoring DAPT includes….
Clinical signs of bleeding
Bloody stools, melena (dark stools), hematemesis, bruising**, oozing from injuries
General tolerability
GI upset
Laboratory testing
RBC, Hb, Hct, platelet count (q6 months)
