IC6 ACS & AIS Flashcards
What does acute coronary syndrome (ACS) mean?
ACS refers to conditions that suddenly reduces blood flow to the heart.
E.g rupture of atherosclerosis
What does chronic coronary syndrome (CCS) mean?
It refers to conditions that are progressive and asymptomatic, that causes reduced blood flow to the heart.
CCS comprises of stable ischaemic heart disease - e.g angina
(Angina occurs when O2 demand is greater than supply)
E.g of CCS: atherosclerosis
What is the most common trigger of an MI?
Rupture of a plaque.
Atherosclerosis is the main risk factor that leads to MI and stroke
What are the 3 criteria to diagnose a pt w MI?
- Widespread/diffused chest pain
- ST elevation
- High troponin level (20,000 - 30,000)
What is the treatment process when a pt has MI?
- Load aspirin
- 100mg OM in pt with existing aspirin
- 300mg in pt that has never taken aspirin - Load ticagrelor/clopidogrel
- Ticagrelor 180mg
- Clopidogrel 600mg
3a. IV UFH/LMWH
3b. IV bolus GPIIb/IIIa
3c. IV fibrinolytics
3d. IV cangrelor - a type of P2Y12i
The IV agents are used when the clot still continues to persist after Ticagrelor or Clopidogrel
Aspirin, ticagrelor, clopidogrel, IV GPIIb/IIIa, IV Cangrelor are all antiplatelets used for ACS.
What other condition share similar presentation to ACS - e.g MI, angina?
Peptic ulcer disease
The largest and most important blood vessel we must know in the heart is:
The Left Anterior Descending Artery (LAD)
The left main artery splits into 2:
1. Left Anterior Descending (LAD) Artery
2. The circumflex artery
What is in-stent thrombosis?
In-stent thrombosis - is where a thrombus forms in the stent
What is in-stent restenosis?
In-stent restenosis - a gradual re-narrowing of the stented segment over 3 to 12 months
What is the mainstay treatment to prevent in-stent thrombosis?
Dual antiplatelet therapy (DAPT)
What drugs have DDIs with antiplatelets?
- Morphine
- Sildenafil, vardenafil
What is the loading and maintenance dose of:
1. Ticagrelor
2. Clopidogrel
- Ticagrelor
- 180mg [loading dose]
- 90mg BD [maintenance dose] - Clopidogrel
- 600mg [loading dose]
- 75mg daily [maintenance dose]
How long should a pt be on DAPT after initiation?
12 months.
Use DAPT for 12 months in both patient with STEMI & NSTEMI.
After 12months, switch to SAPT - Aspirin 100mg OM for life
If a patient on DAPT were to undergo a surgery, what must we stop and for how long?
DAPT are often:
1. Aspirin + Clopidogrel
2. Aspirin + Ticagrelor
If a patient on DAPT were to undergo surgery, we must stop ticagrelor and clopidogrel for 5 days before surgery.
Aspirin will still continue to be taken.
Which is the preferred DAPT?
1. Aspirin + Clopidogrel
2. Aspirin + Ticagrelor
Aspirin + Ticagrelor
Which is more potent? Clopidogrel or Ticagrelor?
Ticagrelor is more potent than clopidogrel
When do we escalate or de-escalate DAPT?
- If patient is on Clopidogrel DAPT, we can escalate to Ticagrelor DAPT if pt is still ischaemic.
- If patient is on Ticagrelor DAPT, we can
de-escalate to Clopidogrel DAPT if pt is at HBR.
If pt is still at HBR even after de-escalation, we can de-escalate further to SAPT.
What monitoring test should I conduct for follow ups on patients on DAPT?
- FBC
- Check for bleeding
c. Dyspnoea - ticagrelor
Ticagrelor affects adenosine levels, which can then lead to dyspnoea and bradycardia.
HASBLED is a bleeding risk score for patients with AF.
What is the other high bleeding risk score?
The 1 major OR 2 minor criteria high bleeding risk score
(I came up with this name myself :’))
What is in the 1 major OR 2 minor criteria HBR score?
Major:
1. *Anticipated long-term use of OAC
2. *Severe CKD (eGFR <30ml/min)
3. *Hgb < 11g/dL
4. *Active malignancy
5. Spontaneous bleed requiring hospitalization within 6 months
6. Liver cirrhosis w portal HTN
(There are 11 major risk factors, but I’ve only typed down the common ones)
Minor:
1. Age ≥75yo
2. Moderate CKD (eGFR 30-50ml/min)
3. Hgb 11-12.9g/dL men, 11-11.9g/dL women
4. Spontaneous bleeding requiring hospitalization within 12 months
5. Long term use of NSAIDs or steroids
6. Any ischaemic stroke after 6 months
How to determine HBR with 1 major OR 2 minor criteria HBR score?
1 major criterion = 2 minor criteria
As long as pt has 1 major criterion, or 2 minor criteria, he/she has HBR.
Which of the 2 P2Y12i is a prodrug?
Clopidogrel is a prodrug
What enzyme metabolises Clopidogrel into its active form?
CYP2C19
If a patient has loss of function (LoF) gene for CYP2C19, how do we go about managing a patient based on:
- Not at HBR
- High bleeding risk
If pt has LoF for CYP2C19, we should not use clopidogrel as it will be poorly metabolised into its active metabolite.
If patient w LoF for CYP2C19 is not at HBR, we use Ticagrelor.
If patient w LoF for CYP2C19 is at HBR, we consider ticagrelor if bleeding risk is still acceptable.
If a patient does not have loss of function (LoF) gene for CYP2C19, how do we go about managing a patient based on:
- Not at HBR
- High bleeding risk
If pt does not have LoF for CYP2C19, we can use clopidogrel as it can be metabolised into its active metabolite.
We can use either clopidogrel or ticagrelor in patients wo LoF for CYP2C19.
What are the 4 common ADRs of ticagrelor?
- Bleeding
- Bradycardia
- Conduction blocks
- Dyspnoea
What are the guidelines used to evaluate the severity of stroke?
(an evaluation after a stroke has happened)
NIHSS - national institution of health stroke scale
mNIHSS - modified national institution of health stroke scale
These 2 guidelines help to determine how an infarction has affected function.
A score of 0-3 on the NIHSS guidelines is considered minor stroke.
What is the guideline used to estimate the risk of ischaemic stroke after a trasient ischaemic attack (TIA)?
(an evaluation after a TIA has happened)
TIA - a “warning stroke” where a blood clot blocks an artery temporarily for a short time, with no permanent damage to the brain.
The ABCD2 guideline
Age:
a. ≥60 yo - 1pt
b. <60yo - 0pt
BP:
a. ≥140/90mmHg - 1pt
b. <140/90mmHg - 0pt
Clinical features:
a. Unilateral weakness - 2pt
b. Isolated speech disturbance - 1pt
c. Other - 0pt
Duration of TIA symptoms:
a. ≥60 mins - 2pt
b. 10 to 59 mins - 1pt
c. <10mins - 0pt
Diabetes:
a. Present - 1pt
b. Absent - 0pt
When ABCD score is ≥4, it is considered high risk TIA.
What should we start in a patient with Acute Ischaemic Stroke (AIS) & is eligible for rTPAs?
If patient has AIS and is eligible for r-TPAs, we can initiate SAPT 24hrs after r-TPAs.
What are the criteria that a patient must fulfill to be eligible for r-TPAs?
Patients eligible for rTPA are:
1. rTPAs can be used within 3-4.5 hrs after symptoms show up
2. Has disabling stroke symptoms
3. BP <185/110mmHg, blood glucose >2.8mml/L
4. CT brain changes
What should we start in a patient with:
- MINOR Acute Ischaemic Stroke (AIS)
& is NOT eligible for rTPAs?
We will start with DAPT immediately for 21 days.
What score on NIHSS is considered minor stroke?
A score of 0-3 on the NIHSS guidelines is considered minor stroke.
Any other score will be considered Not Minor Stroke.
What score on the ABCD2 guideline is considered high risk TIA?
When ABCD score is ≥4, it is considered high risk TIA.
What should we start in a patient with:
- NON-MINOR Acute Ischaemic Stroke (AIS)
& is NOT eligible for rTPAs?
Start SAPT immediately.
What is cardioembolic stroke?
A cardioembolic stroke is when a blood clot or debris is pumped from the heart, to the brain, causing a blockage of the blood vessels.
After analyzing a patient that has experienced a minor stroke, if the patient’s cause of stroke was cardioembolic in nature, should we still use antiplatelets?
Hint: Most cardioembolic stroke are often due to AF.
We will stop antiplatelet therapy and start OAC. This is to target the root cause of the stroke.
If stroke was not cardioembolic in nature, we will follow the usual guidelines:
Minor stroke - DAPT (aspirin w clopidogrel)
Major stroke - SAPT
Start high intensity statin regardless if the stroke is cardioembolic in nature or not. High intensity statin should be used in all patients after a stroke if there are no contraindications.
What are other CV risk factors to manage in stroke patients?
- DM
- LDL
- BP
- Smoking
- Physical activity
