ACC Guidelines: The Main Course (Decision Pathways)

Acute chest pain workup starts with the ECG, and dynamic ischemic changes trump any rapid troponin pathway. The 2022 ACC chest pain decision pathway centers on high-sensitivity troponin I, fast ED disposition, and separating ACS from non-ACS troponin elevation without over-admitting low-risk patients.

ACC Chest Pain Pathway

• ECG first principle: The ECG is the initial screen for dangerous ischemia, and worsening or even transiently normalizing changes should raise concern rather than reassure.
• Ischemic ECG findings: STEMI equivalents matter here: Smith-modified Sgarbossa, posterior STEMI, DeWinter pattern, Wellens, and aVR ST elevation with diffuse ST depression all push patients out of rapid rule-out.
• hs-cTnI requirement: The aggressive ACC rule-out pathways apply only to high-sensitivity troponin I assays, not conventional troponin T or I, so assay-specific cutpoints must be built into your local workflow.
• Single-sample rule-out: A rapid rule-out is possible with symptoms present at least 3 hours, a non-ischemic ECG, and one very low hs-cTnI, with assay-specific values we walk through in the episode.
• Rule-in triggers: Rapid rule-in rests on either an ischemic ECG or a hs-cTnI above the 99th percentile, a reminder that biomarkers and tracings both independently move patients into ACS workup.
• Intermediate troponin pathway: Detectable but nondiagnostic hs-cTnI lives on a continuum, so repeat ECGs and a 2-hour delta troponin become the key next step rather than a binary positive-negative interpretation.

Risk Stratification And Next Steps

• HEART score role: HEART remains one of the best ED predictors of major adverse cardiac events, and ACEP still endorses it even when a troponin pathway has ruled out acute MI.
• Disposition beyond ACS: A low-risk ACC pathway result supports discharge with a non-ischemic ECG, but it does not erase future MACE risk, so follow-up and risk-factor modification still matter.
• Prior test reassurance: Recent negative coronary angiography or calcium scoring within 2 years, or a normal functional test within 1 year, meaningfully lowers near-term concern for obstructive disease.
• Choosing additional testing: Coronary CTA fits patients without known CAD, while stress testing is often favored in known CAD, renal dysfunction, severe contrast allergy, or heavier calcium burden. We get into the practical split in the chapter.
• Renal dysfunction caveat: Most chest pain decision pathways were not well validated in renal dysfunction, so elevated troponin in this group needs more clinical context than an algorithm alone can provide.
• Type I versus II MI: Type I MI reflects acute coronary thrombosis, while Type II MI is supply-demand mismatch; the distinction changes downstream decisions on cath lab activation and antithrombotic therapy.

References:

1. Writing Committee, et al. 2022 ACC Expert Consensus Decision Pathway on the Evaluation and Disposition of Acute Chest Pain in the Emergency Department: A Report of the American College of Cardiology Solution Set Oversight Committee. J Am Coll Cardiol. 2022;80(20):1925-1960. PMID:36241466
2. https://www.acc.org/latest-in-cardiology/ten-points-to-remember/2022/10/10/23/15/2022-acc-expert-consensus-on-chest-pain
3. Amsterdam EA, et al. 2014 AHA/ACC Guideline for the Management of Patients with Non-ST-Elevation Acute Coronary Syndromes: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines [published correction appears in J Am Coll Cardiol. 2014 Dec 23;64(24):2713-4. Dosage error in article text]. J Am Coll Cardiol. 2014;64(24):e139-e228. PMID: 25260718