NSTE-ACS Management Quiz

Management of Non-ST Elevation Myocardial Infarction (NSTE-ACS)

• Identify patients with NSTE-ACS and STEMI based on history and ECG changes, after consultation with ED physician.
• Assess, stabilize, and monitor patient hemodynamics continuously before and during transfer to a hospital.
• Public awareness about heart disease should be increased, to promote early treatment and reduce time to first medical contact (FMC).
• If a person is suspected to have an ACS and isn't on regular aspirin, give 300mg aspirin; chewable/soluble formulations preferred.
• Ambulance responders should be trained and equipped to perform ECGs.
• If ECG shows STEMI or patient with NSTE-ACS has ongoing/recurrent chest pain, transfer immediately to a PCI-capable hospital. High-risk unstable patients should be taken to the nearest hospital for stabilization first.

Emergency Department Management

• Prompt evaluation and initial management upon arrival.
• Patients can be triaged to red or yellow zone using the Malaysian Triage Scale.
• Detailed targeted history and vital signs noted.
• 12-lead ECG within 10 minutes of arrival; compare with pre-hospital/earlier ECGs if available.
• Assess patient for definite STEMI or NSTE-ACS with ongoing chest pain.
• If initial ECG does not show ST elevation but suspected STEMI due to prolonged (>30 minutes) ischaemic chest pain and recurrent/ongoing chest pain, perform steps to confirm/rule out STEMI.
• Repeat ECGs at 15-minute intervals to detect evolving changes.
• Additional posterior and right precordial leads may be helpful in detecting unusual STEMI locations or concomitant RV infarction.
• Patients may fall into three categories: very low likelihood of ACS, definite NSTE-ACS, or possible or suspected NSTE-ACS.

In-Hospital Management

• Venous access established and blood sampled for cardiac biomarkers (hs-cTn preferred).
• Aspirin (300mg) if not already taken.
• Oxygen if SpO2 ≤ 90%.
• GTN sublingual tablet (0.3-0.6mg) or spray (0.4-0.8mg) every 5 minutes for up to three doses if no contraindications.
• Serial ECGs every 10-15 minutes.
• Consider IV GTN and/or morphine as needed.
• Anti-emetic (e.g., metoclopramide, promethazine) administration.
• Monitor for adverse events during morphine administration.
• Consider IV fentanyl as an alternative to IV morphine.
• Use of anti-ischemic drug therapy as needed (consider β-blockers, ACEIs/ARBs, nitrates).
• Consider antiplatelet therapy (clopidogrel, prasugrel, ticagrelor) depending on patient risk.

Antiplatelet Therapy

• ASA (acetylsalicylic acid) recommended loading dose (300mg, chewed/crushed), maintenance dose (75-100mg daily).
• Enteric-coated aspirin not suitable for initial loading dose.
• ASA dose ≤100mg daily if patient taking ticagrelor.
• Consider PPI with DAPT for high-risk gastrointestinal bleeding.
• If allergic/intolerant to aspirin consider alternative P2Y12 inhibitors (e.g., clopidogrel, prasugrel, or ticagrelor) or desensitisation.

P2Y12 Inhibitors

• Clopidogrel, Prasugrel, Ticagrelor are P2Y12 inhibitors.
• loading dose and maintenance doses vary.
• Use of these agents should be considered as part of dual antiplatelet therapy (DAPT).
• Consider duration of DAPT (typically up to 12 months) but consider patient bleeding risk as a factor.
• Choose appropriate P2Y12 based upon patient characteristics (e.g age, weight, bleeding history etc).
• Switching from one P2Y12 inhibitor to another (e.g., ticagrelor to clopidogrel) may be necessary in some situations.

Anticoagulant Therapy

• Consider UFH or LMWH (such as enoxaparin).
• The type and duration of anticoagulation will depend on whether the patient is managed conservatively or invasively, cost and local practice.
• Consider fondaparinux as an alternative anticoagulant.

Other Anti-ischemic Agents

• Beta blockers (β-blockers) are useful in NSTE-ACS patients for managing heart failure and/or left ventricular dysfunction.

Lipid Modifying Drugs (Statins)

• Use statins at high doses (e.g. Atorvastatin 40-80mg or Rosuvastatin 20-40mg).
• Statin therapy should be intensified in patients already taking a low/moderate intensity statin.
• Target LDL-C to be ≤1.8mmol/L (or reduction of 50% from baseline; lower value is better).
• Addition of non-statin therapy (such as ezetimibe and PCSK-9 Inhibitors) may be considered to lower LDL-C if already taking high-dose statins are not effective.

Revascularization Strategies

• Patients at intermediate/high risk for cardiovascular events should be considered for early revascularization.
• Urgent intervention (within 24 hours of hospital admission) is indicated for high-risk patients.
• Routine invasive coronary angiogram not recommended for low-risk patients.

NSTE-ACS in Older Persons

• Age is a significant risk factor for adverse outcomes.
• Older persons with NSTE-ACS more frequently present with symptoms other than chest pain.
• ECGs may be non-diagnostic.
• Cardiac troponins often elevated even without acute coronary syndrome.