What are the differential diagnoses and management plan for a 77‑year‑old woman with a history of aortic dilation, prior myocardial infarction, hypertension, hyperlipidemia, non‑obstructive coronary artery disease, and gastro‑esophageal reflux disease who presents with non‑exertional chest pain radiating to the left jaw, plateaued troponins, non‑ischemic electrocardiogram changes, and a CT scan negative for aortic dissection, pulmonary embolism, and abdominal aortic aneurysm?

Differential Diagnoses and Management Plan

In this 77-year-old woman with plateaued troponins, non-ischemic ECG changes, and negative CT for dissection/PE/AAA, the most likely diagnoses are NSTEMI with non-obstructive CAD (MINOCA), coronary microvascular dysfunction, or esophageal/musculoskeletal causes, with urgent invasive coronary angiography indicated to definitively rule out obstructive disease given her high-risk cardiac history.

Differential Diagnoses (Prioritized by Likelihood)

Cardiac Causes

1. NSTEMI/Unstable Angina with Non-Obstructive CAD

• Despite plateaued troponins, this remains high on the differential given her prior MI, known non-obstructive CAD, and classic radiation pattern to the jaw 1
• Plateaued troponins suggest completed myocardial injury rather than ongoing ischemia
• Non-obstructive mechanisms include plaque rupture with spontaneous recanalization, coronary vasospasm, or microvascular dysfunction

2. Coronary Microvascular Dysfunction (CMD)

• Increasingly recognized in women with chest pain and non-obstructive CAD 2
• Can cause troponin elevation without epicardial stenosis
• Requires specialized testing (coronary function testing, intracoronary imaging) for diagnosis

3. Takotsubo Syndrome

• Should always be considered in elderly women with chest pain and troponin elevation 1
• Typically shows apical ballooning on echocardiography
• Can mimic ACS with ECG changes

4. Aortic Dissection (Despite Negative CT)

• Critical caveat: In patients with known aortic dilation, maintain heightened suspicion even with negative initial CT 3
• Dissection can propagate after initial imaging
• Consider repeat imaging if clinical deterioration occurs or if pain character changes (sudden, ripping, radiating to back) 4, 5
• Her aortic dilation history makes this a "can't miss" diagnosis requiring ongoing vigilance

5. Acute Decompensated Aortic Stenosis

• Given her age and cardiac history, undiagnosed severe aortic stenosis could cause angina-like symptoms
• Check for systolic murmur, narrow pulse pressure

Non-Cardiac Causes

6. GERD/Esophageal Spasm

• Known GERD history makes this plausible
• Can cause chest pain radiating to jaw
• However, troponin elevation argues against purely esophageal etiology

7. Musculoskeletal Pain

• Less likely given jaw radiation and troponin elevation
• Would expect reproducible pain with palpation

Immediate Management Algorithm

Step 1: Risk Stratification (Already Completed)

• ✓ High-sensitivity troponin at 0h and 1h (appears done - plateaued) 1
• ✓ ECG within 10 minutes (done - non-ischemic) 1
• ✓ CT imaging excluding dissection/PE/AAA (done)

Step 2: Urgent Diagnostic Workup

Echocardiography (STAT)

• Assess for:
  • Regional wall motion abnormalities (suggests NSTEMI or Takotsubo)
  • Apical ballooning pattern (Takotsubo)
  • Aortic valve pathology and severity
  • Pericardial effusion (late dissection complication) 3
  • Left ventricular function
• This is mandatory before proceeding 1, 6

Invasive Coronary Angiography (ICA)

• Strongly recommended within 24 hours given:
  • Plateaued troponins indicating myocardial injury
  • High-risk history (prior MI, known CAD)
  • Age and multiple cardiovascular risk factors
• ICA remains gold standard to exclude obstructive disease and guide management 1
• Can identify MINOCA, spontaneous coronary artery dissection (SCAD), or vasospasm 2

Step 3: Ongoing Monitoring

Continuous telemetry and serial troponins

• Monitor for arrhythmias
• Repeat troponin at 3 hours if clinical condition changes 1
• Watch for sudden clinical deterioration suggesting dissection propagation 3

Serial blood pressure monitoring in both arms

• Blood pressure differential >20 mmHg suggests dissection despite negative CT 4
• Check distal pulses bilaterally

Step 4: Medical Management

Current Appropriate Therapy:

• Aspirin 81-325 mg (if not already given)
• High-intensity statin (continue/initiate)
• Beta-blocker for heart rate/blood pressure control
• ACE inhibitor or ARB (given HTN and prior MI)

Hold anticoagulation until dissection definitively excluded and ICA performed 3, 7

Avoid thrombolytics - absolutely contraindicated given aortic dilation history and dissection risk 8

PPI for GERD - continue home regimen

Critical Pitfalls to Avoid

1. Do not dismiss aortic dissection based solely on negative CT - dissection can occur after initial imaging in patients with aortic dilation 3. Maintain vigilance for 24-48 hours.

2. Do not assume "plateaued troponins" mean no intervention needed - this indicates completed myocardial injury requiring definitive diagnosis via ICA 1.

3. Do not attribute symptoms to GERD without excluding cardiac causes - troponin elevation demands cardiac workup 6.

4. Do not start dual antiplatelet therapy or anticoagulation before echocardiography - if dissection develops, these medications are catastrophic 3, 7, 8.

5. Do not rely on "typical" vs "atypical" chest pain classification - women and elderly patients frequently present with non-classic symptoms 6, 2.

Disposition

• Admit to monitored cardiac unit (already done)
• Urgent cardiology consultation for ICA planning
• Consider cardiac surgery consultation given aortic dilation history if any concern for aortic pathology emerges
• Length of stay will depend on ICA findings and need for revascularization

If ICA Shows Non-Obstructive CAD (MINOCA)

• Cardiac MRI to assess for myocarditis, Takotsubo, or microvascular dysfunction 2
• Consider intracoronary imaging and coronary function testing 2
• Phenotype-specific treatment based on underlying mechanism 2