What initial diagnostic work‑up (chest radiograph, 12‑lead electrocardiogram, CBC with differential, basic metabolic panel, liver panel, high‑sensitivity troponin, and BNP/NT‑proBNP) should be ordered for an afebrile patient with flu‑like symptoms, systolic blood pressure in the 160 mm Hg range, audible wheezing, and a history of chronic systolic heart failure and hypertension?

Diagnostic Work-Up for Suspected Acute Heart Failure Decompensation

Immediate Mandatory Testing

This patient requires a comprehensive diagnostic panel immediately to differentiate acute heart failure decompensation from alternative diagnoses and assess for life-threatening precipitants. Given the presentation of flu-like symptoms, elevated blood pressure (160s mmHg), audible wheezing, and known chronic systolic heart failure, this represents a potential acute heart failure (AHF) syndrome requiring urgent evaluation. 1

Core Laboratory Panel (Class I Recommendation)

The following blood tests must be ordered immediately upon presentation: 1

• High-sensitivity cardiac troponin – Essential to identify acute coronary syndrome as a precipitant, which would mandate urgent invasive strategy within 2 hours. Troponin elevation also provides independent prognostic information beyond BNP in heart failure patients. 1, 2, 3, 4

• BNP or NT-proBNP – Critical for differentiating cardiac from non-cardiac causes of dyspnea and wheezing. Normal levels (BNP <100 pg/mL or NT-proBNP <300 pg/mL) make AHF unlikely. Combined with troponin, provides superior risk stratification for mortality and rehospitalization. 1, 2, 3, 4

• Complete blood count with differential – Identifies anemia (alternative cause of symptoms), infection (pneumonia precipitant), or other hematologic abnormalities. 1

• Basic metabolic panel – Including sodium, potassium, BUN/creatinine, and glucose. Renal dysfunction and electrolyte abnormalities are common precipitants and predict poor outcomes. The patient's multiple medications (spironolactone, losartan) increase hyperkalemia risk. 1

• Liver function tests – Hepatic congestion from right-sided heart failure or hypoperfusion causes abnormal liver enzymes, which identify high-risk patients. 1

Essential Imaging Studies (Class I Recommendation)

• 12-lead electrocardiogram – Must be obtained immediately. Rarely normal in AHF (high negative predictive value), and essential for identifying acute myocardial ischemia, rapid atrial fibrillation, or other arrhythmic precipitants requiring urgent intervention. 1, 5

• Chest radiograph – Mandatory to assess for pulmonary venous congestion, pleural effusion, interstitial/alveolar edema, and cardiomegaly. Also identifies alternative diagnoses like pneumonia or pulmonary malignancy. Note that up to 20% of AHF patients have near-normal chest X-rays, so normal findings do not exclude the diagnosis. 1, 5

Echocardiography Timing

• Immediate echocardiography is NOT required in this hemodynamically stable patient (SBP 160s). 1

• Echocardiography within 48 hours is recommended when cardiac structure/function may have changed since previous studies or to assess response to therapy. 1

• Immediate echocardiography IS mandatory only if the patient develops hemodynamic instability, cardiogenic shock, or suspected acute mechanical complications (valve rupture, ventricular septal defect). 1

Clinical Reasoning and Diagnostic Algorithm

Why This Comprehensive Panel Is Critical

The combination of elevated blood pressure (160s mmHg) with wheezing in a patient with chronic systolic heart failure strongly suggests hypertensive acute heart failure with pulmonary congestion. 1 However, the "flu-like symptoms" and negative infectious testing create diagnostic uncertainty requiring systematic exclusion of:

1. Acute coronary syndrome – Troponin identifies this life-threatening precipitant requiring immediate revascularization. 1

2. Pneumonia or pulmonary infection – Chest X-ray and CBC with differential differentiate this from cardiac pulmonary edema. 1

3. Severe anemia – CBC identifies this alternative cause of dyspnea and wheezing. 1

4. Acute renal failure – BMP/creatinine assesses this precipitant and guides diuretic dosing. 1

Prognostic Stratification

The combination of high-sensitivity troponin and BNP/NT-proBNP provides superior risk stratification compared to either biomarker alone. 2, 3, 4 In patients with elevated NT-proBNP >1000 pg/mL, adding high-sensitivity troponin identifies those at 8.5-fold increased mortality risk and 4.8-fold increased rehospitalization risk. 2 This dual biomarker approach is complementary and most beneficial when evaluated together. 3, 4

Critical Pitfalls to Avoid

• Do not assume wheezing equals asthma/COPD – Cardiac asthma from pulmonary congestion mimics bronchospasm and requires entirely different management. Chest X-ray differentiates these. 1

• Do not delay testing for "stable" vital signs – SBP 160s represents hypertensive emergency in the context of AHF and requires urgent blood pressure reduction within minutes to hours. 1

• Do not omit troponin because "it's not chest pain" – Troponin elevation occurs in 50-70% of AHF patients without acute coronary syndrome and provides critical prognostic information. 2, 3, 4, 6

Additional Monitoring

Beyond the initial diagnostic panel, continuous monitoring should include: 1, 5

• Pulse oximetry – Assess for hypoxemia (SpO₂ <90%) requiring supplemental oxygen. 1, 5
• Continuous blood pressure monitoring – Guide vasodilator therapy titration. 1, 5
• Urine output measurement – Target >0.5 mL/kg/h; inadequate response (<100 mL/h over 1-2 hours) requires diuretic dose escalation. 1, 5
• Daily weights and strict intake/output – Monitor decongestion response. 5, 7