New ACC/AHA Guidelines for Acute Coronary Syndrome (ACS) Management: Key Updates for Clinicians

The American College of Cardiology (ACC) and the American Heart Association (AHA) have released a comprehensive guideline on the management of acute coronary syndrome (ACS), combining recommendations for ST-elevation myocardial infarction (STEMI) and non-ST-elevation ACS (NSTE-ACS). This update integrates recent evidence and reflects a contemporary approach to coronary revascularization, intracoronary imaging, mechanical circulatory support, and secondary prevention.

---

Key Updates in ACS Management

1. Complete Revascularization

• Complete revascularization is now a Class 1 recommendation for both STEMI and NSTE-ACS.
• A single procedure approach is preferred over a staged approach (2021 Coronary Revascularization Guidelines).

2. Intracoronary Imaging

• Intravascular ultrasound (IVUS) or optical coherence tomography (OCT) is now a Class 1 recommendation during percutaneous coronary intervention (PCI) in patients with left main or complex lesions.
• This update follows RCT data demonstrating improved stent-related and clinical outcomes (OCTIVUS Meta-Analysis).

3. Mechanical Circulatory Support (Impella)

• The Impella CP device, a microaxial intravascular flow pump, receives a Class 2a recommendation for selected patients with STEMI and severe or refractory cardiogenic shock.
• This follows the DanGer Shock trial, which showed survival benefits but also highlighted risks of peripheral arterial complications (DanGer Shock Trial).

4. Blood Transfusion in ACS

• Liberal red blood cell transfusion to maintain hemoglobin ≥10 g/dL in patients with acute MI and anemia receives a Class 2b recommendation.
• This stems from findings in the MINT trial, which suggested potential reductions in cardiac death (MINT Trial).

5. Dual Antiplatelet Therapy (DAPT) and Bleeding Risk Reduction

• DAPT (aspirin + P2Y12 inhibitor) for at least 12 months remains a Class 1 recommendation for patients at low bleeding risk.
• Ticagrelor monotherapy after 1 month is an option for patients with high bleeding risk.
• Proton pump inhibitors (PPIs) should be used in patients at risk of gastrointestinal bleeding.

6. Lipid Management and Secondary Prevention

• Lipid panel measurement is recommended 4 to 8 weeks after starting or adjusting lipid-lowering therapy.
• If LDL remains ≥70 mg/dL despite statin therapy, adding a nonstatin agent (ezetimibe, PCSK9 inhibitors, inclisiran, or bempedoic acid) is a Class 1 recommendation.
• If LDL is between 55-69 mg/dL, adding a nonstatin is reasonable (Class 2a).
• Cardiac rehabilitation is strongly recommended before discharge (Class 1), and home-based programs are a reasonable alternative (Class 2a).

---

What Clinicians Should Know

• Class 1 recommendations should be widely implemented as they have strong evidence of benefit.
• Class 2a recommendations (e.g., Impella) indicate that procedures may be beneficial but require careful patient selection.
• Class 2b recommendations (e.g., liberal transfusion strategies) suggest potential benefit but require further validation.
• Class 3 recommendations (Do Not Do) include:
  • Manual aspiration thrombectomy in primary PCI for STEMI.
  • Routine PCI of non-infarct-related arteries in ACS patients with cardiogenic shock.
  • Routine use of glycoprotein IIb/IIIa inhibitors due to increased bleeding risk.

---

Take-Home Points

1. Complete revascularization in ACS patients is now a Class 1 recommendation.
2. IVUS and OCT should be used during PCI for left main and complex lesions.
3. Impella may improve survival in selected cardiogenic shock patients, but risks must be considered.
4. DAPT remains critical, but strategies to minimize bleeding risk should be individualized.
5. Aggressive LDL lowering is essential for secondary prevention.
6. Cardiac rehabilitation is a must, and home-based programs can be considered.

The implementation of these evidence-based recommendations will be key to improving patient outcomes in ACS management.

For further details, read the full guideline publication in the Journal of the American College of Cardiology and Circulation.