Acute Coronary Syndrome Management: What Every Hospitalist, Physician Assistant, and Nurse Practitioner Should Know About the 2025 ACC/AHA ACS Guideline

Acute Coronary Syndrome Management: A Hospitalist Guide to the 2025 ACC/AHA ACS Guideline

Acute coronary syndrome remains one of the most time-sensitive problems encountered in hospital medicine.

A patient may arrive with:

• Crushing chest pressure
• Dyspnea
• Diaphoresis
• Nausea
• Syncope
• Epigastric discomfort
• Unexplained weakness
• Hemodynamic instability

Or the presentation may be much less obvious.

For hospitalists, physicians, physician assistants, and nurse practitioners, the challenge is not simply recognizing a classic STEMI.

It is distinguishing acute coronary syndrome from its mimics, interpreting troponin correctly, recognizing high-risk NSTEMI, understanding antithrombotic therapy, coordinating timely invasive management, identifying complications, and building a reliable transition from acute treatment to secondary prevention.

The 2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes brings STEMI and NSTE-ACS management together in a unified contemporary guideline.

This review focuses on the parts most relevant to clinicians caring for hospitalized adults.

Clinical note: This article is intended for professional education and is not a substitute for the complete guideline, local STEMI/ACS protocols, cardiology consultation, emergency response systems, institutional policies, or patient-specific clinical judgment. Acute coronary syndrome is time-sensitive. Unstable patients and suspected STEMI require prompt evaluation and appropriate escalation rather than delayed reference review.

What Does Acute Coronary Syndrome Include?

Acute coronary syndrome encompasses:

• Unstable angina
• Non-ST-segment elevation myocardial infarction (NSTEMI)
• ST-segment elevation myocardial infarction (STEMI)

The 2025 guideline primarily addresses ACS caused by acute atherothrombotic coronary disease—typically plaque rupture or erosion followed by thrombosis.

That distinction matters.

Not every elevated troponin represents type 1 myocardial infarction.

And not every myocardial infarction is caused by acute plaque rupture.

Hospitalists regularly encounter troponin elevation in patients with:

• Sepsis
• Tachyarrhythmia
• Severe anemia
• Hypoxemia
• Hypertensive emergencies
• Pulmonary embolism
• Heart failure
• Kidney disease
• Shock
• Critical illness

The first task is therefore not:

“Is the troponin elevated?”

It is:

“Does this patient’s presentation represent acute myocardial ischemia, and if so, what mechanism is most likely?”

The First Minutes: Recognize ACS Quickly

When ACS is suspected, the initial evaluation should move quickly.

The 2025 guideline recommends obtaining and interpreting a 12-lead ECG within 10 minutes of presentation.

If the initial ECG is nondiagnostic but suspicion remains high—particularly with persistent symptoms or clinical deterioration—serial ECGs should be obtained.

Cardiac troponin should also be measured as soon as possible, preferably with a high-sensitivity assay.

If the initial result is nondiagnostic, serial measurement is important.

For high-sensitivity cardiac troponin assays, repeat measurements are generally obtained earlier than with conventional assays according to the assay and validated clinical pathway.

The Hospitalist’s Initial ACS Questions

When evaluating possible ACS, ask:

1. Is the Patient Stable?

Look immediately for:

• Hypotension
• Shock
• Ongoing severe ischemic symptoms
• Malignant arrhythmia
• Acute pulmonary edema
• Severe hypoxemia
• Altered mental status
• Mechanical complication
• Cardiac arrest

Instability changes the urgency.

2. Is There Evidence of Acute Ischemia?

Integrate:

• Symptoms
• ECG
• Troponin
• Hemodynamics
• Examination
• Clinical trajectory

Do not interpret any one element in isolation.

3. Could This Be STEMI or Another Occlusive Emergency?

Do not allow a reassuring initial biomarker to delay recognition of a concerning ECG and clinical presentation.

Troponin may not yet be elevated early in the course.

4. Could Another Dangerous Diagnosis Explain the Presentation?

Important alternatives may include:

• Aortic dissection
• Pulmonary embolism
• Pneumothorax
• Pericarditis
• Myocarditis
• Esophageal rupture
• Severe gastrointestinal disease
• Other causes of shock or respiratory distress

The diagnosis of ACS should emerge from the entire clinical picture.

ECG: More Than “STEMI or No STEMI”

The ECG remains central to early assessment.

Hospitalists should recognize:

• ST-segment elevation
• ST-segment depression
• Dynamic ischemic changes
• T-wave abnormalities
• New conduction abnormalities in clinical context
• Posterior infarction patterns
• Right ventricular involvement
• Arrhythmias

A normal or nonspecific ECG does not automatically exclude ACS.

If symptoms persist or suspicion remains high, reassessment and serial ECGs matter.

One particularly important clue is ST depression in the anterior precordial leads that may suggest posterior infarction.

When appropriate, additional leads can help clarify the diagnosis.

High-Sensitivity Troponin: Powerful but Easy to Misuse

High-sensitivity cardiac troponin has transformed the evaluation of suspected myocardial infarction.

But an elevated value does not automatically equal ACS.

Troponin indicates myocardial injury.

The clinician must determine the cause.

Ask:

• Is there a rise or fall?
• Are there ischemic symptoms?
• Are there ischemic ECG changes?
• Is there imaging evidence supporting ischemia?
• Is another acute illness causing myocardial injury?
• Does the presentation fit type 1 MI?

This distinction is particularly important for hospitalists because hospitalized patients frequently have conditions that elevate troponin without acute coronary thrombosis.

STEMI: Reperfusion Is the Priority

For patients with STEMI, rapid reperfusion remains central.

Primary PCI is generally the preferred reperfusion strategy when it can be performed within the recommended system-of-care timeframe.

When timely PCI cannot be achieved, fibrinolytic therapy may be appropriate for selected patients presenting within the appropriate time window when there are no contraindications, followed by transfer to a PCI-capable center.

Hospitalists working in facilities without PCI capability should know their institution’s:

• STEMI activation pathway
• Transfer process
• Fibrinolysis protocol
• Contraindications
• Transport arrangements

This is not a situation in which clinicians should reconstruct the entire guideline from memory while the patient waits.

Use the established STEMI system.

NSTEMI Is Not “STEMI Lite”

NSTEMI encompasses a broad spectrum of risk.

Some patients are stable.

Others have:

• Ongoing ischemia
• Hemodynamic instability
• Heart failure
• Significant arrhythmia
• High-risk anatomy
• Recurrent symptoms
• Markedly abnormal biomarkers

The 2025 guideline recommends an invasive approach during hospitalization for patients with NSTE-ACS who are at intermediate or high risk for ischemic events, with intent to proceed with revascularization when appropriate.

Lower-risk patients require individualized risk stratification.

The practical hospitalist lesson is:

NSTEMI management should be risk based, not label based.

Aspirin Remains Foundational

Aspirin remains a central component of ACS treatment unless contraindicated.

But modern ACS antiplatelet therapy extends beyond aspirin.

Most patients will also require a P2Y12 inhibitor as part of dual antiplatelet therapy.

The specific drug and duration depend on factors including:

• PCI
• Bleeding risk
• Ischemic risk
• Need for oral anticoagulation
• Planned surgery
• Coronary anatomy
• Other patient characteristics

Dual Antiplatelet Therapy: Know the Default—and the Exceptions

For patients with ACS who are not at high bleeding risk, the 2025 guideline uses aspirin plus an oral P2Y12 inhibitor for at least 12 months as the default DAPT strategy.

For patients undergoing PCI, ticagrelor or prasugrel is generally preferred over clopidogrel in appropriate ACS patients.

But the modern approach is not simply:

“Everyone gets 12 months of identical therapy.”

Bleeding risk matters.

The guideline includes strategies for reducing bleeding in selected patients.

These include considerations such as:

• Proton pump inhibitor therapy for patients at gastrointestinal bleeding risk
• Selected transition to P2Y12 inhibitor monotherapy after PCI
• Modified therapy when long-term oral anticoagulation is required

Hospitalists should therefore understand the final antithrombotic plan, not merely copy “DAPT” into the discharge summary.

ACS Plus Long-Term Anticoagulation Requires Special Attention

Some ACS patients also require chronic anticoagulation for conditions such as atrial fibrillation.

Combining:

• Aspirin
• A P2Y12 inhibitor
• An oral anticoagulant

increases bleeding risk.

The 2025 guideline supports shortening aspirin exposure after PCI in many patients who require long-term anticoagulation, while continuing an oral anticoagulant plus a P2Y12 inhibitor—preferably clopidogrel—according to the recommended strategy and individual circumstances.

These regimens are easy to misunderstand during transitions of care.

Before discharge, make sure the record clearly states:

• Which antithrombotic drugs are being used
• Why
• When aspirin should stop, if applicable
• How long the P2Y12 inhibitor is intended
• Which anticoagulant continues
• Who will reassess therapy
• Relevant bleeding precautions

This is an area where cardiology, pharmacy, hospital medicine, and outpatient follow-up should be aligned.

Anticoagulation During Acute ACS

Parenteral anticoagulation remains part of acute management for many ACS patients.

The appropriate agent depends on factors including:

• STEMI versus NSTE-ACS
• PCI strategy
• Fibrinolysis
• Kidney function
• Bleeding risk
• Timing of angiography
• Institutional protocol

This is another area where local ACS pathways and cardiology guidance are preferable to a one-size-fits-all medication list.

Beta Blockers: Use Clinical Judgment

The 2025 guideline recommends early oral beta-blocker therapy—generally within the first 24 hours—in ACS patients without contraindications.

But “early beta blocker” does not mean “beta blocker regardless of physiology.”

Use caution when there is concern for:

• Cardiogenic shock
• Low-output state
• Significant hypotension
• Severe bradycardia
• Advanced conduction disease
• Other relevant contraindications

The guideline supports low-dose oral initiation with adjustment according to heart rate, blood pressure, and clinical response.

This is particularly important because aggressive early beta blockade in the wrong patient can be harmful.

Lipid Management Starts in the Hospital

The ACS hospitalization is an opportunity to establish aggressive secondary prevention.

The 2025 guideline recommends high-intensity statin therapy for all ACS patients unless contraindicated or not tolerated.

The guideline also gives clinicians the option of initiating ezetimibe concurrently in appropriate patients.

For patients already receiving maximally tolerated statin therapy:

• Addition of a nonstatin lipid-lowering agent is recommended when LDL-C remains ≥70 mg/dL
• Further intensification is reasonable for selected high-risk patients with LDL-C 55 to <70 mg/dL

Potential nonstatin agents include:

• Ezetimibe
• PCSK9 monoclonal antibodies
• Inclisiran
• Bempedoic acid

The practical lesson is:

Do not postpone secondary prevention until months after discharge.

The hospitalization is an opportunity to establish the plan.

Recheck Lipids After Discharge

The guideline recommends reassessing a fasting lipid panel approximately 4 to 8 weeks after initiation or adjustment of lipid-lowering therapy.

That follow-up should not disappear into generic discharge language.

The transition plan should identify:

• What therapy was started
• What the LDL-C goal/threshold strategy is
• When lipids should be reassessed
• Who will follow the result
• What escalation may be considered

Radial Access Is Preferred for PCI

For ACS patients undergoing PCI, the 2025 guideline recommends a radial approach over femoral access when appropriate.

The evidence supports reductions in:

• Bleeding
• Vascular complications
• Mortality

This is primarily an interventional decision, but hospitalists caring for patients before and after PCI should understand why radial access has become the preferred strategy.

Intravascular Imaging Has a Stronger Role

One important 2025 update is the recommendation for intravascular imaging to guide PCI in ACS patients with complex coronary lesions.

This reflects the growing role of tools such as:

• Intravascular ultrasound
• Optical coherence tomography

in optimizing PCI in selected patients.

For hospitalists, the practical implication is less about performing the procedure and more about understanding the contemporary PCI report and subsequent treatment plan.

Complete Revascularization Is an Important Theme

The 2025 guideline supports a strategy of complete revascularization in both STEMI and NSTE-ACS patients when appropriate.

But this does not mean every stenosis should be treated immediately in every patient.

Decisions depend on:

• Coronary anatomy
• Lesion complexity
• Comorbidities
• Clinical stability
• PCI versus CABG considerations
• Timing
• Cardiogenic shock

For STEMI with multivessel disease, treatment of significant nonculprit lesions may occur during the same procedure or as a staged strategy depending on the situation.

Cardiogenic Shock Is Different

ACS complicated by cardiogenic shock requires a different mindset.

Priorities include:

• Rapid recognition
• Hemodynamic assessment
• Culprit-vessel revascularization
• Appropriate critical-care support
• Multidisciplinary coordination

Emergency revascularization of the culprit vessel remains fundamental.

However, routine PCI of non-infarct-related arteries during the initial procedure in ACS with cardiogenic shock is not recommended.

That distinction is important:

Complete revascularization in stable ACS does not mean routine immediate multivessel PCI during cardiogenic shock.

For a broader approach to shock physiology, escalation, and the deteriorating inpatient, see Critical Care for Hospitalists.

Mechanical Circulatory Support: Selection Matters

The 2025 guideline incorporates newer evidence concerning microaxial flow pumps in selected patients with acute MI complicated by cardiogenic shock.

For appropriately selected patients, use may be reasonable.

But the potential benefits come with important risks, including:

• Bleeding
• Limb ischemia
• Renal complications
• Vascular complications

This is not a routine intervention for every patient with shock.

Patient selection and experienced multidisciplinary management matter.

Anemia and Transfusion: A Notable 2025 Update

Transfusion thresholds in ACS have been debated for years.

The 2025 guideline states that red blood cell transfusion to maintain a hemoglobin concentration around 10 g/dL may be reasonable in patients with ACS and acute or chronic anemia who are not actively bleeding.

The wording matters:

may be reasonable

is not the same as:

every ACS patient with hemoglobin below 10 should automatically receive blood.

The decision should incorporate:

• Symptoms
• Ischemia
• Hemodynamics
• Hemoglobin trajectory
• Bleeding
• Comorbidities
• Overall clinical context

Watch for Mechanical and Electrical Complications

After MI, hospitalists should remain alert for complications such as:

• Acute heart failure
• Cardiogenic shock
• Ventricular arrhythmias
• Bradyarrhythmias
• Conduction disease
• Recurrent ischemia
• Mechanical complications
• Pericardial complications
• Left ventricular thrombus in appropriate contexts

A patient who deteriorates after an apparently successful reperfusion requires reassessment rather than an assumption that the ACS problem has already been solved.

Heart Failure After ACS

ACS and heart failure frequently overlap.

A patient may develop:

• Pulmonary edema
• Reduced ejection fraction
• Cardiogenic shock
• New valvular dysfunction
• Right ventricular failure
• Persistent congestion

The hospitalist should distinguish:

routine post-MI care

from:

a patient developing a new hemodynamic syndrome.

Our Heart Failure in Hospital Medicine guide covers inpatient congestion, decongestion, GDMT, cardiorenal physiology, discharge readiness, and related issues in greater detail.

Discharge Is Part of ACS Treatment

A technically successful PCI does not complete ACS management.

Before discharge, review:

ANTITHROMBOTIC THERAPY

• Aspirin
• P2Y12 inhibitor
• Anticoagulation if indicated
• Intended duration
• Bleeding precautions

LIPID THERAPY

• High-intensity statin
• Nonstatin therapy when appropriate
• Follow-up lipid testing

CARDIAC MEDICATIONS

• Beta blocker when appropriate
• Other indicated secondary-prevention therapies
• Medication reconciliation

CARDIAC FUNCTION

• Left ventricular function when assessed
• Heart-failure implications
• Relevant structural complications

RISK-FACTOR MANAGEMENT

• Tobacco use
• Blood pressure
• Diabetes
• Lipids
• Physical activity
• Other modifiable cardiovascular risks

FOLLOW-UP

• Cardiology
• Primary care
• Lipid reassessment
• Medication monitoring
• Cardiac rehabilitation

A vague instruction to:

“Follow up with cardiology”

is not a complete transition plan.

Cardiac Rehabilitation Should Be Part of the Plan

The 2025 guideline recommends referral to cardiac rehabilitation before discharge.

For patients unable or unwilling to participate in traditional center-based rehabilitation, home-based options may be considered when appropriate and available.

Hospitalists can help prevent cardiac rehabilitation from becoming an afterthought by including the referral in the discharge workflow.

Medication Access Matters

An evidence-based prescription has limited value if the patient cannot obtain it.

Before discharge, consider:

• Insurance coverage
• Copay
• Prior authorization
• Pharmacy availability
• Understanding of the regimen
• Complexity
• Drug interactions
• Bleeding risk
• Follow-up

This is especially important with:

• P2Y12 inhibitors
• Anticoagulants
• Nonstatin lipid-lowering therapy
• Other newer or higher-cost medications

The Discharge Summary Should Explain the ACS Story

A useful discharge summary should make the major cardiovascular decisions easy to understand.

Consider including:

• STEMI/NSTEMI diagnosis
• Culprit lesion when known
• PCI/CABG or other intervention
• Stent information when relevant
• Residual coronary disease
• Left ventricular function
• Important complications
• Antiplatelet plan
• Anticoagulation plan
• Lipid-lowering plan
• Medication changes
• Cardiac rehabilitation referral
• Follow-up
• Pending studies

For broader principles of clinically useful transitions and note-writing, see our Hospitalist Documentation guide.

Common ACS Pitfalls for Hospitalists

Avoid these shortcuts:

“Troponin is elevated, therefore NSTEMI.”

Troponin elevation indicates myocardial injury. Determine the mechanism.

“The first ECG is normal, therefore ACS is excluded.”

Serial assessment may be needed when suspicion remains high.

“The patient had PCI, so the acute problem is finished.”

Watch for recurrent ischemia, arrhythmia, heart failure, shock, bleeding, and mechanical complications.

“DAPT means aspirin plus another agent for exactly 12 months in everyone.”

Twelve months is the default in patients without high bleeding risk, but individual antithrombotic strategies vary.

“Complete revascularization means fix every lesion immediately.”

Timing and strategy depend on clinical context; cardiogenic shock is an important exception.

“Hemoglobin below 10 means transfuse.”

The guideline’s recommendation is more nuanced.

“Discharge medications can be sorted out later.”

Secondary prevention begins during hospitalization.

“Cardiac rehab is optional paperwork.”

It is part of guideline-directed secondary prevention.

A Practical Hospitalist ACS Checklist

Use this as an educational cognitive aid—not a substitute for your institution’s ACS pathway.

INITIAL ASSESSMENT

• Hemodynamic stability assessed
• 12-lead ECG obtained promptly
• Serial ECG considered when needed
• High-sensitivity troponin obtained
• Serial troponin planned when appropriate
• STEMI/occlusive emergency considered
• Dangerous alternative diagnoses considered
• Cardiology/STEMI pathway activated when appropriate

EARLY MANAGEMENT

• Aspirin addressed
• P2Y12 strategy clarified
• Anticoagulation strategy clarified
• Reperfusion/invasive strategy defined
• Beta-blocker appropriateness assessed
• High-intensity statin initiated or continued
• Bleeding risk considered
• Kidney function and medication dosing reviewed

AFTER PCI OR REVASCULARIZATION

• Culprit lesion understood
• Residual disease reviewed
• Access site monitored
• Antithrombotic plan confirmed
• Recurrent ischemia monitored
• Arrhythmias monitored
• Heart failure/shock reassessed
• LV function reviewed when available

DISCHARGE

• Final ACS diagnosis clear
• DAPT regimen and intended duration documented
• Anticoagulation plan clear when applicable
• Lipid-lowering plan established
• Follow-up lipid testing planned
• Medication access assessed
• Cardiac rehabilitation referral addressed
• Cardiology follow-up arranged
• Patient understands warning symptoms
• Discharge summary communicates key cardiovascular decisions

How This Fits With Other Hospitalist Clinical Resources

This page should own:

2025 ACS guideline

acute coronary syndrome management for hospitalists

NSTEMI/STEMI inpatient management

ACS antithrombotic and secondary-prevention updates

The Clinical Guidelines Every Hospitalist Should Know in 2026 page should remain the annual guideline hub and link here from its acute coronary syndrome section.

The 100 Hospitalist Cases page should own case-based clinical reasoning.

The 100 Hospitalist Clinical Pearls page should own rapid memory aids.

The Heart Failure in Hospital Medicine page should own acute decompensated heart failure and inpatient HF management.

The Critical Care for Hospitalists page should own shock physiology, acute deterioration, escalation, and ICU transitions.

That creates a clear clinical-reference structure rather than several broad pages competing for the same inpatient-medicine queries.

Where Continuing Medical Education Fits

ACS management demonstrates why continuing education matters in hospital medicine.

The 2025 guideline incorporates newer evidence affecting:

• Antiplatelet therapy
• Bleeding-risk mitigation
• Lipid lowering
• Invasive management
• PCI technique
• Complete revascularization
• Cardiogenic shock
• Mechanical circulatory support
• Transfusion
• Secondary prevention

But a CME activity should not replace the guideline itself.

Clinicians should use continuing education to:

• Understand major changes
• Discuss difficult cases
• Identify knowledge gaps
• Examine the evidence
• Generate questions for deeper review

Then return to authoritative guidance when making important clinical decisions.

Hospitalists and inpatient clinicians looking for structured education can review current Hospitalist CME opportunities and compare the curriculum with their learning needs.

Key Takeaways From the 2025 ACS Guideline

For hospitalists, some of the most useful takeaways are:

1. Obtain and interpret the ECG quickly.

The guideline retains a goal of ECG acquisition and interpretation within 10 minutes for suspected ACS.

2. Use high-sensitivity troponin appropriately.

Troponin identifies myocardial injury; the clinical context determines whether ACS is responsible.

3. Think in terms of risk, not simply STEMI versus NSTEMI.

Higher-risk NSTE-ACS generally warrants an invasive strategy during hospitalization.

4. DAPT remains foundational.

Twelve months remains the default for ACS patients without high bleeding risk, but modern strategies increasingly individualize therapy according to bleeding and anticoagulation considerations.

5. Start secondary prevention before discharge.

High-intensity statin therapy, appropriate lipid intensification, follow-up testing, and cardiac rehabilitation belong in the inpatient plan.

6. Radial PCI is preferred when appropriate.

The guideline strengthens contemporary procedural strategies, including intravascular imaging for complex lesions.

7. Complete revascularization is important—but shock is different.

Routine nonculprit PCI during the initial procedure is not recommended in ACS complicated by cardiogenic shock.

8. Transfusion guidance has evolved.

A strategy targeting hemoglobin around 10 g/dL may be reasonable in selected ACS patients with anemia who are not actively bleeding; this is not a universal transfusion trigger.

9. The hospitalist’s job continues after the cath lab.

Medication reconciliation, bleeding surveillance, heart-failure assessment, discharge planning, rehabilitation referral, and secondary prevention remain essential parts of inpatient ACS care.

Final Thoughts

The 2025 ACS guideline is more than an update to STEMI and NSTEMI protocols.

It reinforces a continuum of care:

Recognize ischemia quickly.

Interpret ECG and troponin in context.

Reperfuse or pursue invasive management when appropriate.

Balance thrombosis against bleeding.

Recognize shock and complications.

Begin secondary prevention before discharge.

Build a reliable transition to outpatient care.

For hospitalists, PAs, and NPs, the key is not memorizing every recommendation.

It is knowing which decisions are time-sensitive, which recommendations have changed, which patients need immediate cardiology or critical-care involvement, and where to find the authoritative guidance when the details matter.

For current hospital medicine education, explore upcoming CME Getaways conferences.

ACS care does not end when the artery is opened. The inpatient team still has to turn successful acute treatment into a safe long-term plan.

Primary Reference

Rao SV, O’Donoghue ML, Ruel M, et al. 2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline for the Management of Patients With Acute Coronary Syndromes. Journal of the American College of Cardiology and Circulation. 2025.