Acute Coronary Syndrome

Acute Coronary Syndrome – Treatment Options

Introduction
Acute coronary syndrome (ACS) refers to a spectrum of clinical presentations resulting from acute myocardial ischemia due to reduced coronary blood flow. It encompasses unstable angina (UA), non–ST-segment elevation myocardial infarction (NSTEMI), and ST-segment elevation myocardial infarction (STEMI). Prompt diagnosis and management are critical to prevent myocardial necrosis, preserve cardiac function, and reduce mortality.

1. Immediate Stabilization (Initial Emergency Care)

• Airway, breathing, circulation (ABC): Ensure stability.

• Oxygen: Administer if SpO₂ < 90%.

• Cardiac monitoring: Continuous ECG, blood pressure, and oxygen saturation monitoring.

• IV access: Establish for drug administration.

2. Initial Medical Therapy (MONA-B Approach)

• Morphine: IV for persistent chest pain unrelieved by nitrates (use cautiously).

• Oxygen: If hypoxemic.

• Nitrates (sublingual nitroglycerin): For chest pain relief unless contraindicated (hypotension, RV infarction, PDE-5 inhibitor use).

• Aspirin: 160–325 mg chewed immediately (antiplatelet loading).

• Beta-blockers: Initiate orally within 24 hours unless contraindicated (hypotension, bradycardia, asthma).

3. Antithrombotic Therapy

• Dual antiplatelet therapy (DAPT):

  • Aspirin + P2Y12 inhibitor (clopidogrel, prasugrel, or ticagrelor).

• Anticoagulation:

  • Unfractionated heparin (UFH), enoxaparin, or bivalirudin during hospitalization or PCI.

4. Reperfusion and Invasive Strategies

• STEMI (complete coronary occlusion):

  • Primary percutaneous coronary intervention (PCI): Preferred, ideally within 90 minutes of first medical contact.

  • Thrombolytic therapy (e.g., alteplase, tenecteplase): If PCI unavailable within 120 minutes and no contraindications.

• NSTEMI/Unstable Angina:

  • Early invasive strategy (PCI within 24–72 hours) for high-risk patients.

  • Conservative strategy with medical stabilization in low-risk patients.

5. Secondary Medical Therapy (Post-Stabilization)

• High-intensity statin (atorvastatin, rosuvastatin): Initiate early regardless of baseline LDL.

• ACE inhibitors/ARBs: For left ventricular dysfunction, diabetes, hypertension, or STEMI.

• Aldosterone antagonists (eplerenone, spironolactone): For patients with EF ≤ 40% and heart failure or diabetes, if not contraindicated.

• Beta-blockers: Continued long-term unless contraindicated.

• DAPT continuation: For at least 12 months post-PCI, depending on stent type and bleeding risk.

6. Supportive and Preventive Measures

• Smoking cessation, diet modification, weight control, and exercise as part of cardiac rehabilitation.

• Blood pressure, diabetes, and lipid management to reduce recurrence risk.

• Vaccination: Influenza vaccination is recommended for all patients with cardiovascular disease.

7. Complication Management

• Arrhythmias: Managed with antiarrhythmics, cardioversion, or pacing.

• Heart failure/cardiogenic shock: Treated with diuretics, vasopressors, inotropes, or mechanical circulatory support (IABP, ECMO).

• Mechanical complications (e.g., ventricular septal rupture, papillary muscle rupture): Require urgent surgical repair.

8. Multidisciplinary Care

• Cardiologists (interventional and non-interventional): For acute management and long-term care.

• Cardiac surgeons: For coronary artery bypass grafting (CABG) in multivessel disease or failed PCI.

• Rehabilitation specialists: For structured cardiac rehabilitation.

• Primary care and nursing teams: For follow-up and risk factor modification.