STEMI

Question 1

What is the definition of ST Elevation Acute Coronary Syndrome (STE-ACS) or STEMI?

Answer 1

A clinical syndrome resulting from an imbalance in myocardial oxygen supply and demand, characterized by chest pain/discomfort >30 mins (often with activity/stress), associated symptoms (dyspnea, palpitations, sweating), and ECG changes showing ST elevation.

Question 2

What are the three main goals of initial management for STEMI?

Answer 2

Pain relief.
Establishing early reperfusion.
Treatment of complications.

Question 3

What are the two primary reperfusion strategies for STEMI? When is reperfusion indicated?

Answer 3

Primary Percutaneous Coronary Intervention (PCI)
Fibrinolytic Therapy
Indicated in patients with symptoms of ischemia <12 hours duration and persistent ST-segment elevation.

Question 4

Which reperfusion strategy is generally superior for STEMI? Under what condition?

Answer 4

Primary PCI is superior to fibrinolysis when performed in a timely manner at an experienced center.

Question 5

What are the key components of concomitant drug therapy for STEMI patients (general list)?

Answer 5

Anti-platelet therapy (DAPT)
Anticoagulant (may include DOACs in specific contexts, but parenteral initially)
ACE Inhibitor / ARB (if no contraindications)
Beta-blocker (if no contraindications)
Mineralocorticoid Antagonist (MRA) (if indicated, e.g., HF/LVEF ≤40%)
Statins (High-intensity)

Question 6

What are the two main types of fibrinolytic agents mentioned for STEMI? Give an example of each.

Answer 6

Non-fibrin specific: Streptokinase (antigenic)
Fibrin specific: Tenecteplase (more rapid reperfusion, preferred)

Question 7

How should the dose of Tenecteplase be adjusted for patients >75 years old?

Answer 7

The dose should be reduced by 50%.

Question 8

What anticoagulant therapy is recommended following administration of a fibrin-specific agent (like Tenecteplase)?

Answer 8

Anticoagulation (Heparin or Enoxaparin) is recommended and continued for at least 48 hours. Fondaparinux (2.5mg/day) is an alternative, continued for 8 days or until discharge.

Question 9

List 3 absolute contraindications to fibrinolytic therapy.

Answer 9

(Any 3 of):
* History of intracranial bleed
* History of ischemic stroke within 3 months
* Known structural cerebral vascular lesion (e.g., AVM)
* Known intracranial neoplasm
* Active bleeding or bleeding diathesis (excluding menses)
* Significant head trauma within 3 months
* Suspected aortic dissection

Question 10

List 3 relative contraindications to fibrinolytic therapy.

Answer 10

(Any 3 of):
* Severe uncontrolled hypertension (BP > 180/110 mmHg)
* Ischemic stroke > 3 months ago
* History of chronic, severe uncontrolled hypertension
* Current anticoagulant use (INR > 2) or DOAC use
* Recent major surgery (< 3 weeks)
* Traumatic/prolonged CPR (> 10 min)
* Recent internal bleeding (within 4 weeks)
* Non-compressible vascular puncture
* Active peptic ulcer
* Pregnancy
* Prior exposure (>5 days, < 12 months) to streptokinase (if planning to use it again)

Question 11

What is the primary goal of management in the Emergency Department (ED) for STEMI?

Answer 11

Restore coronary blood flow as quickly as possible to limit myocardial damage.

Question 12

What are the key steps in the initial assessment of a patient presenting with suspected STEMI in the ED?

Answer 12

ABC Assessment (Airway, Breathing, Circulation) - Assess and stabilize.
ECG: Perform 12-lead ECG immediately (< 10 min) to confirm STEMI.
History and Physical Examination.

Question 13

What are the key initial pharmacological interventions in the ED for STEMI?

Answer 13

• Oxygen: If O2 sat < 95% (Target >95%).
• Morphine: For pain relief.
• SL GTN: 1 dose if chest pain persists (Avoid if SBP < 90 mmHg).
• Aspirin: 300mg soluble/chewable, if not given earlier.
• P2Y12 Inhibitor: Clopidogrel (300mg) or Ticagrelor (180mg) if not given earlier (higher doses if primary PCI planned).
• Initiate Reperfusion strategy discussion/activation (PCI preferred within 90 min of FMC).

Question 14

What are the target timeframes for initiating Primary PCI if a patient presents to a PCI-capable vs. non-PCI capable center?

Answer 14

PCI-capable center: < 90 minutes from first medical contact (FMC).
Non-PCI capable center: < 120 minutes from FMC (transfer time included).

Question 15

If Primary PCI cannot be performed within 120 minutes, what is the recommended reperfusion strategy? What is the ‘golden hour’?

Answer 15

Fibrinolytic therapy. The ‘golden hour’ refers to initiating treatment within 2 hours from symptom onset, which can significantly reduce mortality.

Question 16

What antiplatelet therapy (DAPT) should ALL patients undergoing Primary PCI for STEMI receive? Specify loading and maintenance doses.

Answer 16

• Loading Dose: Aspirin 300mg + [Clopidogrel 300-600mg OR Ticagrelor 180mg OR Prasugrel 60mg (after angiogram)].
• Maintenance Dose: Aspirin 75-150mg daily + [Clopidogrel 75mg daily OR Ticagrelor 90mg BID OR Prasugrel 10mg daily]. Duration usually up to 1 year (shorter, e.g., 6 months, if high bleed risk).

Question 17

What antiplatelet therapy (DAPT) should patients receiving fibrinolytic therapy for STEMI receive? Specify loading and maintenance doses.

Answer 17

Loading Dose: Aspirin 300mg + [Clopidogrel 300mg (if ≤75 yrs) OR Clopidogrel 75mg (if >75 yrs)].
Maintenance Dose: Aspirin 75-150mg daily + Clopidogrel 75mg daily. Duration between 1 month to 1 year.

Question 18

What is the role of Beta-blockers post-STEMI (secondary prevention)?

Answer 18

Reduce myocardial oxygen demand. Recommended for patients with HF, LV systolic dysfunction (unless contraindicated), start when hemodynamically stable.

Question 19

When should ACE inhibitors/ARBs be started post-STEMI? In which patients are they particularly indicated?

Answer 19

Indicated starting within the first 24 hours in all patients (unless contraindicated), especially high-risk patients: LVEF ≤40%, evidence of HF, or Diabetes Mellitus.

Question 20

When should Mineralocorticoid Receptor Antagonists (MRAs - spironolactone, eplerenone) be considered post-STEMI?

Answer 20

In patients already on ACEi/BB with LVEF ≤40% AND either Heart Failure symptoms or Diabetes Mellitus, provided no significant renal failure or hyperkalemia.

Question 21

What is the target LDL-C for high-intensity statin therapy post-STEMI?

Answer 21

LDL-C < 1.8 mmol/L OR a reduction of at least 50% from baseline.

Question 22

What is the routine recommendation for oral nitrates post-STEMI?

Answer 22

Oral nitrates are NOT routinely recommended but can be considered for ongoing chest pain, ischemia, HF, or Hypertension.

Question 23

When might CCBs be used post-STEMI?

Answer 23

As an alternative to Beta-blockers (if contraindicated/not tolerated) or for patients with ongoing angina. (Avoid non-DHPs like verapamil/diltiazem if LVEF is low).

Question 24

Summarize the key components of antithrombotic therapy in the CCU post-fibrinolysis (if no PCI).

Answer 24

DAPT (Aspirin + Clopidogrel)
Anticoagulation (UFH or LMWH preferred, esp. if >75yo/renal impairment) for at least 48h (Fondaparinux alternative).

Question 25

Summarize the key components of antithrombotic therapy in the CCU post-PCI.

Answer 25

DAPT (Aspirin + Clopidogrel/Ticagrelor/Prasugrel) - Duration depends on bleed risk (typically 6-12 months). +/- GP IIb/IIIa inhibitor during PCI if high thrombus burden. Anticoagulation typically stopped after PCI unless other indication (e.g., AF).

Question 26

What anticoagulant is preferred for STEMI patients >75 years old or with renal impairment who received fibrinolytics?

Answer 26

LMWH (enoxaparin) is preferred over UFH.

Question 27

When might Fondaparinux be used in STEMI?

Answer 27

As an anticoagulant alternative, particularly in patients not undergoing PCI and not receiving fibrinolytic therapy, or as an alternative post-fibrinolysis.

Question 28

When are Oral Anticoagulants (OACs - Warfarin or DOACs) prescribed post-STEMI? What is the typical combined regimen?

Answer 28

Prescribed for patients with an additional indication for anticoagulation, such as Atrial Fibrillation (AF) or LV thrombus, who also underwent PCI (requiring DAPT initially). The regimen is often 'triple therapy' (OAC + DAPT) for a short period, then transition to OAC + single antiplatelet, then OAC alone.

Question 29

What is the target INR when using Warfarin + DAPT post-STEMI with AF? How long is this combination typically used?

Answer 29

INR target: 2.0. Duration of triple therapy: Typically 1-6 months, depending on bleeding vs. ischemic risk.

Question 30

Describe a typical DOAC + DAPT regimen for post-STEMI patients with AF. How long is it used?

Answer 30

Examples: Dabigatran (110/150 BID) + Aspirin + Clopidogrel (1-6 mo) -> DOAC + AP mono (6 mo) Rivaroxaban (15 OD) + Aspirin + Clopidogrel (1-6 mo) -> DOAC + AP mono (6 mo) Rivaroxaban (2.5 BD) + Aspirin + Clopidogrel (1-12 mo) - CV prevention dose Apixaban (5 BID) + Aspirin + Clopidogrel (6 mo) Duration varies based on risk; often followed by DOAC + single antiplatelet.

Question 31

For a stable patient >1 year post-STEMI/PCI with AF, what is the recommended antithrombotic therapy?

Answer 31

Warfarin or DOAC should be used. Concomitant antiplatelet therapy should NOT be prescribed routinely.

Question 32

What are the key components of Long-Term Management & Secondary Prevention Post-STEMI?

Answer 32

Pharmacology Therapy (DAPT, Statin, ACEi/ARB, BB, MRA as indicated) Lifestyle modification & Risk factor control (Smoking cessation, Diet, Exercise, BP control, Diabetes control) Cardiac rehabilitation.