What is the most likely diagnosis and immediate management for a 72‑year‑old woman with recent myocardial injury (elevated troponin), elevated B‑type natriuretic peptide indicating heart‑failure physiology, no peripheral edema, and who is taking duloxetine, a fentanyl transdermal patch, hydrocodone as needed, albuterol inhaler for asthma, levothyroxine for hypothyroidism, sumatriptan for migraine, and trazodone for sleep?

Diagnosis and Management of a 72-Year-Old Woman with Elevated Troponin and BNP

This patient most likely has acute myocardial injury (troponin 2.9 ng/mL) with underlying heart failure (BNP 498 pg/mL), requiring immediate serial troponin measurements, 12-lead ECG, and echocardiography to distinguish between Type 1 myocardial infarction, Type 2 MI from supply-demand mismatch, or acute decompensated heart failure.

Immediate Diagnostic Steps

Serial Troponin Testing

• Obtain troponin measurements at 3-6 hour intervals from the initial ER value to establish whether there is a rising/falling pattern (≥20% change) characteristic of acute myocardial injury versus stable chronic elevation 1, 2
• A single elevated troponin is insufficient because 10-15% of patients may not show initial elevation despite true myocardial injury 1, 2
• The troponin level of 2.9 ng/mL is approximately 30-290 times the upper reference limit (depending on assay), indicating significant myocardial damage that requires aggressive evaluation 2

ECG Assessment

• Obtain a 12-lead ECG immediately to identify ST-segment elevation (STEMI), ST-segment depression ≥1 mm, new T-wave inversions, or conduction abnormalities 1, 2
• If the initial ECG is nondiagnostic but clinical suspicion remains high, repeat ECGs every 15-30 minutes during the first hour 2
• Look specifically for left ventricular hypertrophy with strain pattern given her hypertension history 2

Clinical Context Assessment

• Assess for ischemic symptoms: chest pain lasting >20 minutes, dyspnea, diaphoresis, or anginal equivalents 2
• Document vital signs: heart rate >120 bpm or severe hypertension >180/110 mmHg suggest Type 2 MI from supply-demand mismatch 2
• Examine for signs of acute heart failure: pulmonary edema, elevated jugular venous pressure, new cardiac murmurs 2

Differential Diagnosis

Cardiac Causes (Most Likely)

Type 1 Myocardial Infarction (Acute Coronary Syndrome)

• If troponin shows rising/falling pattern with ischemic symptoms or ECG changes, this represents NSTEMI requiring urgent intervention 1, 2
• Troponin >5 times upper limit of normal has >90% positive predictive value for Type 1 MI 2

Type 2 Myocardial Infarction

• Supply-demand mismatch from tachycardia, severe hypertension, or anemia without coronary thrombosis 2
• Accounts for approximately 5% of troponin elevations 2

Acute Decompensated Heart Failure

• BNP 498 pg/mL indicates elevated left ventricular filling pressure and heart failure physiology 1
• Chronic heart failure produces persistent troponin elevation through ongoing wall stress and myocyte injury 2, 3
• The absence of peripheral edema does not exclude heart failure, as pulmonary congestion can occur without systemic edema 1

Tachyarrhythmia

• Atrial fibrillation or other rapid arrhythmias increase myocardial oxygen demand and can cause troponin elevation without coronary occlusion 2
• Check for irregular pulse or palpitations 2

Non-Cardiac Causes to Consider

Pulmonary Embolism

• Can cause right ventricular strain leading to troponin elevation, especially with dyspnea or chest pain 2, 4

Chronic Kidney Disease

• Particularly when serum creatinine >2.5 mg/dL, leads to continuously elevated troponin due to reduced clearance and coexisting cardiac disease 2
• Check baseline renal function 2

Sepsis or Critical Illness

• Systemic inflammation and demand ischemia frequently elevate troponin in hospitalized elderly patients 2, 4

Management Algorithm

If Rising/Falling Troponin Pattern (≥20% Change) with Ischemic Symptoms or High-Risk ECG Features

Diagnose NSTEMI and initiate ACS protocol:

• Administer aspirin 162-325 mg immediately 2
• Add P2Y12 inhibitor (ticagrelor or prasugrel preferred) 2
• Start anticoagulation with unfractionated heparin or low-molecular-weight heparin 2
• Calculate GRACE risk score; if >140, arrange urgent coronary angiography within 24 hours 2
• Consider GP IIb/IIIa inhibitor (eptifibatide or tirofiban) in high-risk patients proceeding to angiography 2

If Stable/Flat Troponin Without Ischemic Symptoms or ECG Changes

Focus on identifying and treating underlying cause:

• Perform bedside echocardiography to assess left ventricular function, ejection fraction, regional wall motion abnormalities, and diastolic function 1, 2
• Evaluate for tachyarrhythmias (check for atrial fibrillation given age and hypertension) 2
• Assess for acute decompensated heart failure: initiate diuretics if volume overload is present 1
• Check renal function (creatinine, eGFR) to assess for chronic kidney disease contribution 2
• Consider pulmonary embolism if dyspnea is prominent: obtain D-dimer or CT pulmonary angiography 2

Medication Review and Considerations

Current medications that may contribute:

• Duloxetine 100 mg twice daily: can cause hypertension and tachycardia, potentially contributing to Type 2 MI 2
• Fentanyl patch 25 mcg and hydrocodone: opioids can mask ischemic symptoms 4
• Albuterol inhaler: beta-agonist can cause tachycardia increasing myocardial oxygen demand 2
• Sumatriptan: contraindicated in coronary artery disease due to coronary vasoconstriction risk 2

Prognostic Implications

• Any troponin elevation confers approximately three-fold increased risk of death or myocardial infarction at 30 days, independent of underlying cause 2
• The magnitude of troponin elevation (2.9 ng/mL) correlates directly with mortality risk 2, 3
• Elevated troponin in heart failure patients is associated with impaired hemodynamics, progressive left ventricular dysfunction, and increased mortality 3
• Combined elevation of troponin and BNP further worsens prognosis 3

Critical Pitfalls to Avoid

• Do not rely on a single troponin measurement from the ER two weeks ago; obtain fresh serial measurements to distinguish acute from chronic injury 1, 2
• Do not dismiss troponin elevation in an elderly patient with hypertension as "false positive"—it reflects genuine myocardial injury with adverse prognosis 2
• Do not attribute troponin elevation solely to renal dysfunction without evaluating cardiac status 2
• Troponin may remain elevated for 7-14 days after an acute event; a new rise >20% indicates possible recurrent infarction 2
• The absence of peripheral edema does not exclude heart failure—focus on BNP elevation and pulmonary findings 1

Recommended Immediate Actions

1. Admit to monitored telemetry unit for continuous cardiac monitoring 2
2. Obtain serial troponins at 3-6 hour intervals starting now 1, 2
3. Perform 12-lead ECG immediately and repeat if symptoms change 2
4. Order bedside echocardiogram to assess ventricular function and wall motion 1, 2
5. Check complete metabolic panel including renal function 2
6. Cardiology consultation if rising troponin pattern or high-risk features present 2
7. Consider stress testing or coronary angiography based on troponin kinetics and clinical presentation 2