Acute Coronary Syndrome Flashcards
ACS Categorization
a) Unstable Angina
b) Myocardial Infarction
i) STEMI
ii) NSTEMI
What is the averge age of first ACS?
Late 60”s
ACS occurs more in (males/females) ration
Male to female ratio 3:2
ER Assesments of MI
1) Patient story
2) 12 ECG
3) Blood Tests –> Indicators of cell death
A normal ECG is good evidence of….
Strong evidence to rule OUT ACS
Physicians will investigate other possible causes of sx’s (heartburn, gallbladder attack, etc)
St Segment Depression Indicates
Strong evidence for coronary ischemia
However, ST depression is often associated with stable (fixed obstruction) angina. Further investigations will be needed to determine severity
ST Elevation
A marker of complete coronary obstruction causing cardiac myocyte death
This finding suggests a serious MI requiring urgent revascularization in most cases
If blood flow is not restored quickly, the person is at high risk for major consequences such as heart failure, arrythmias, or even death.
ST segment elavtion is refrred to as a
STEMI
Q-waves in normal ECG
Absent
Q waves in MI
Often will appear following (or during) a STEMI
Usually indicates extensive damage (transmural) to the heart wall
Often remains in the ECG for life (even after the acute event)
a STEMI will be confirmed if….
if evidence of cell death is observed
What are the most sensitive and specific marker of MI?
Tropnins
Cardiac tropinins in MI
are the most sensitive and specific biomarkers in the context of ACS
Troponins ↑ in the blood within hrs of MI and remain elevated for several days
The major classic presentation of STEMI is
ST elevation is a classic presentation of a major MI
Often leaves ECG evidence forever (Q-wave)
What is left-bundle branch block?
Conduction in the left bundle of his is slow
Results in delayed depolarization of the left ventricle
left Bundle Branch Block presnetation on ECG
QRS is delayed (>0.12sec)
Broad monomorphic R waves in I and V6 with no Q waves
Broad monomorphic S waves in V2, may have a small r wave
CRP is a test that indicates…
Inflammation
tests adminstered in the E.R. if STEMI suspected….
ECG
Cardiac troponins (3 – 6 hrs after symptom onset)
Natriuretic peptides (B-type or pro-B type –> Brain Naturietic Peptide elvated in MI)
CXR
Standard TX in ER
Oxygen (if O2 sats <90% or respiratory distress, etc)
ASA +/- ADP inhibitor
S/L NTG (IV NTG should be started if pain continues)
Ask about PDE5 inhibitor use!!!
Beta-blocker may be considered but onset slow and dangerous in acute setting if evidence of reduced CO, HF, or bradycardia
IV anticoagulation – recommended for all patients with suspected MI regardless of initial treatment strategy (e.g., UFH, enoxaparin, bivalirudin)
Old A** Never Beat Attacks
A beta-blocker should only be used once a pt is…..
STABLE
BB benfit has (increased/decreased) ove rthe years?
Decreased
Why has the benfit of BB decreased over the years?
Post MI risk is generally lower today due to frequency of mechanical revascularization and medication use
In other words, people experiencing MIs are less likely to have damaged myocardium (or less myocardium is damaged)
Less damage likely means lower levels of epi/norepi. These SNS hormones can cause adverse outcomes. They also are the likely mechanism for BB protection
Betab-blockers are highly….
Beta-blockers are highly protective in people who have experienced damage to myocardial cells
If there is more damage, a BB is….
More damage = higher SNS = more likely to benefit from BB
if there is less damage, a BB is …..
Less damage = lower SNS = less likely to benefit from BB
What is the first goal of a STEMI? Timing
Repurfusion
ALL patients presenting with STEMI with symptom onset within past 12 hours should receive reperfusion therapy (assuming eligibility criteria are met)
Primary PCI is the preferred method of reperfusion when done in a timely fashion
If PCI cannot be performed within 2hrs after first medical contact, fibrinolytic medications should be administered.
(tPA) –> Plasminogen to plasmin which breaks down fibrin
Why is repurfusion tx benficial?
Reperfusion as quickly as possible after a STEMI has great potential to restore blood, ↓ the risk for damaged myocardium, and ↓ the risk of death
Before a PCI, what drugs are given….
DAPT
Anticoagulant TX
Why are pre-PCI antiplatelet tx used?
Antiplatelets are started PRIOR to PCI procedures
Helps protect against platelet activation that occurs during placement of stents
Stent placement can cause endothelial damage
What drugs can be used in PRe-PCL antiplatlet tx? DOses? Which drug not used when?
ASA - 81-325 (325 if not taking 81 already)
Loading dose of P2Y12 inhibitor (either of the following)
Clopidogrel 600mg
Prasugrel 60mg
Ticagrelor 180mg
Prasugrel should NOT be used to patients with prior history of stroke or TIA**
When is Pre-PCI antiplatlet tx initiated?
Administered in ED as soon as possible after decision for PCI
What anticoagulants can be used before PCI?
Options include:
LMWH –> enoxaparin
UFH
Bivalirudin
Are IV anticoagulants always used before PCI?
YES
Clopidogrel is adminstered as a….
Pro-drug –> requires liver activation –> May be a disadvantage for some
Clopidogrel inhibits
ADP receptor
Clopidogrel Inhibition Type
irreversible
Prasurgrel MOA…
ADP receptor antagonits
Prasurgrel is adminstered as… Comparison to clopidogrel?
Pro-drug –> Less intra-subject variability in conversion than Clopidogrel
Prasurgrel Concerns for Usage
Concern regarding risk of serious bleeding in
Patients >75 yrs
Patients < 60kg
Ticagrelor administration
Not a pro-drug
Ticagrelor binding to ADP receptor
Reversible Inhibitor of ADP receptor (only one)
STEMI Meds DAY 1
ABCDEK Mechanism + angina pain
ASA + Ticagrelor
Bispropol
ramipril
Statin
NTG
In DAPT, what is preferred over Clopidogrel?
Ticagrelor and Prasurgrel
DAPT is used for how long…
1 year and then re-evaluate
At 1 year, on DAPT, need to….
Determine bleeding risk:
If not at high risk, Continue DAPT for 3 years
- ASA 81 mg OD, Ticagrelor 60 mg BID or Clopidogrel 75 mg OD
If high risk, SAPT –> ASA 81, or Clopidogrel 75 mg OD
(1975)
DAPT for 1 year Combos
ASA 81 OD
Ticagrelor 90 BID
Prasurgrel 10 mg OD
Clopidogrel 75 mg OD
Risk factors for bleeding…
Need for OAC, NSAIDs, or prednisone
Age > 75
Frailty
Anemia with Hb < 110
CrCl < 40ml/min
Body weight < 60kg
Bleeding hosp within previous year
Prior stroke/intracranial bleed
If high bleeding risk, DAPT can be…
If bleeding risk is high, DAPT d/c can generally be considered
After 1 month for a BMS
After 3 months for a DES
Indications for BB post MI
LVSD / Heart failure – absolute indication (not in acute phase)
Arrhythmia – absolute indication
STEMI – absolute indication
STEMI without residual dysfunction – 3 years and re-evaluate (AHA)
NSTEMI without residual dysfunction – “consider” BB
ACE-i in M.I. What if ACE not tolerated?
Shown to ↓ mortality in patients with recent MI – used in virtually ALL people with MI (HOPE TRIAL)
- Can use an ARB
What ACEi to use in people with increased risk of ADR’s
Short acting ACEI (captopril or enalapril)
if significant renal dysfunction, ACEi…..
If significant renal dysfunction, may wish to wait till kidney’s are stabilized (SCr improved)
ACEi are considered in all high risk pt’s without HTN
TRUE
Speciifc s/e of ACEi
Cough, Increased K+, Angioedema
Drug Interactions of ACei
Anything that increases K+
Anything decreases renal perfusion
C.I. of ACEi
- Teratogenic
- Bilateral renal artery stenosis
History of angioedema - First line in renal dz –> But need to monitor
What other class of drugs may be prescribed?
MRA –> Eplerenone
Adding MRA to BB and ACEi in post MI benfit? This does not apply when…
Adding eplerenone to BB and ACEI in the post-MI setting to patients with EF<40% was associated with ↓ mortality
Does NOT apply IF significant renal dysfx (Cr > 170) or high K
MRA is only given to people who present with….
heart failure after that heart attack
what revascularization technique is preferred?
PCI
CABG in STEMI when….
Urgent CABG indicated when coronary anatomy not amenable to PCI AND ischemia persists (or cardiogenic shock, severe HF, etc)
CABG risks….
much higher risk for bleeding during the procedure.
Before CABG, ____should be stopped and ____ should be used….
ADP inhibitors –> ASA should be used before surgery
Elective CABG Meds Before Surgery
In NON-URGENT situations, ADP inhibitors should be d/c for at least 5 days before surgery!!!
Uregent Situation - Primary CABG DAPT USe
If CABG is urgent, ADP inhibitors should be stopped at least 24hrs before surgery
Post CABG Anti-platlet tx depends on….
Depends on situation
STEMI or NSTEMI eligible for DAPT
Elective CABG ASA only
NSTEMI vs. Unstable ANgina DIagnosis
History of classic ischemic sx’s not relieved by rest
ST-DEPRESSION on ECG
If cell death can be proven in the context of ACS and ST depression, Jibby will be diagnosed with a NSTEMI (troponins positive – if positive, MI – if negative, unstable angina)
If NO cell death can be proven in the context of ACS and ST depression, Jibby will be diagnosed with unstable angina
In order to be diagnosed with MI….
Cardiac cell death must be dtermined
What is a primary PCI? What are the features favouring PCI?
Some patients will be sent for angiography (and possible PCI) very quickly (invasive strategy)
Features favouring invasive strategy
STEMI
Refractory angina
Hemodynamic/electrical instability
High risk features (Diabetes, previous MI, HF, etc)
BB receommended for….
LVSD / Heart failure – absolute indication (not in acute phase)
Arrhythmia – absolute indication
STEMI – absolute indication
STEMI without residual dysfunction – 3 years and re-evaluate (AHA)
NSTEMI without residual dysfunction – “consider” BB
Atrial Fib Define and Consequence
An arrhythmia of the atrium removing the atrial contraction altogether
Clots can form in the left atrium due to pooling of blood
These clots can embolize into the carotid artery and cause ischemia to the brain (i.e., stroke)
Atrial FIb Tx
Anticoagulants (i.e., not antiplatelets) are effective for this condition
ACS with Atrial FIb Tx
Makes the use of DAPT more likely to cause bleeding
However, antiplatelets are still necessary for treating ACS
AFIB Elective PCI w/t High risk features for thrombotic CV events
Dual Therapy
OAC and C;lopidogrel 1-12 months
AFIB ACS with PCI or Elective PCI with High risk Features fro Thrombotic CV events
Triple Tx –> OAC + ASA + clopidogrel –> 1day to 1 month
Dual Tx –> OAC + clopidogrel for up to 12 onths
AFIB and ACS w/t PCI
Dual Tx
OAC and Clopidogrel
Unstable Angina TX
Similar to Fixed Obstruction –> DAPT could be avoided
