What is the recommended approach for an adult patient with a history of respiratory issues, such as asthma or Chronic Obstructive Pulmonary Disease (COPD), or cardiovascular conditions like heart failure, presenting with respiratory or cardiovascular symptoms?

Recommended Approach for Adults with Respiratory or Cardiovascular History Presenting with Symptoms

Begin with chest radiography as the first-line imaging modality for any adult patient with a history of asthma, COPD, or heart failure presenting with respiratory or cardiovascular symptoms. 1

Initial Clinical Assessment

History and Physical Examination Focus

• Document specific respiratory symptoms: dyspnea severity, chest pain characteristics, wheezing, cough, and any history of air travel intolerance with respiratory symptoms (dyspnea, chest pain, confusion, or syncope). 1
• Assess cardiovascular symptoms: exertion-related dizziness, chest pain, palpitations, edema, and exercise tolerance. 1, 2
• Identify comorbidities worsened by hypoxemia: cerebrovascular disease, coronary artery disease, heart failure. 1
• Recent clinical events: hospitalization within 6 weeks for acute respiratory illness, recent pneumothorax, or major thoracic surgery. 1

Vital Signs and Orthostatic Assessment

• Measure blood pressure in both sitting and standing positions at every visit to detect orthostatic hypotension, which is critical in patients with cardiovascular disease. 2
• Measure oxygen saturation by pulse oximetry from a warm ear or finger after sufficient delay for stable reading; blood gas tensions are preferred if hypercapnia is known or suspected. 1

Diagnostic Testing Algorithm

First-Line Imaging

• Chest radiography (PA and lateral) is the initial imaging study for patients with unclear etiology of symptoms, suspected COPD exacerbation, suspected pleural or chest wall disease, or suspected diaphragm dysfunction. 1, 2
• Chest radiography can evaluate for heart failure, cardiac chamber enlargement, pulmonary hypertension, comorbidities, complications, and alternative diagnoses. 1, 2

When to Advance to CT Imaging

• CT chest without IV contrast is appropriate as second-line imaging if chest radiograph is abnormal or symptoms persist despite normal radiograph. 1
• CT is superior for distinguishing, characterizing, and assessing extent of pleural and chest wall abnormalities. 1

Cardiac Evaluation in Patients with Respiratory History

Critical distinction: Approximately 20% of patients with COPD have concomitant heart failure, and up to 35% of patients with heart failure have COPD. 3, 4

Immediate Cardiac Testing Required

• 12-lead electrocardiogram immediately in patients with at least one coronary heart disease risk factor and poor exercise tolerance. 2
• BNP or NT-proBNP measurement can distinguish heart failure from respiratory causes in patients presenting with acute dyspnea, particularly in those with history of asthma or COPD. 1, 4
  • At BNP cutpoint of 100 pg/mL: sensitivity 93.1%, specificity 77.3%, negative predictive value 97.7% for detecting new-onset heart failure in patients with pulmonary disease history. 4
  • Caveat: BNP may be falsely low in obese patients despite true heart failure. 2

When to Perform Echocardiography

• Two-dimensional echocardiography with Doppler is indicated for patients with signs of congestive heart failure and/or concerning symptoms such as exertion-related dizziness or chest pain, with or without history of respiratory failure. 1, 2
• Echocardiography assesses left ventricular ejection fraction, LV size, wall thickness, and valve function. 2

Advanced Cardiac Testing Considerations

• Baseline resting ECG should be considered, as 20% of individuals with COPD entering pulmonary rehabilitation have ischemic ECG changes. 1
• Cardiopulmonary exercise testing may be considered in patients with multiple potential factors contributing to activity intolerance, to characterize mechanisms of exercise impairment and guide safe exercise prescription. 1
• Coronary arteriography is reasonable for patients presenting with heart failure who have chest pain (cardiac or non-cardiac origin) without prior coronary anatomy evaluation and no contraindications to revascularization. 1

Pulmonary Function Testing

• Spirometry is recommended in the pre-flight or pre-rehabilitation assessment for patients with severe COPD, asthma, or restrictive disease. 1
• Maximal exercise testing with measurement of respiratory gas exchange is reasonable to identify high-risk patients with heart failure who are candidates for cardiac transplantation or other advanced treatments. 1

Specialized Testing for Specific Presentations

For Suspected Pulmonary Hypertension

• Transthoracic echocardiography as immediate next step to screen for pulmonary hypertension. 5
• Right heart catheterization is mandatory before initiating any pulmonary hypertension-specific therapy. 5
• Ventilation-perfusion (V/Q) scanning must be performed to rule out chronic thromboembolic pulmonary hypertension, with sensitivity >90% and specificity >94%. 5

For Suspected Diaphragm Dysfunction

• Chest radiography initially to assess diaphragm position and provide clues to paralysis. 1
• Fluoroscopy is useful as secondary evaluation for focused functional assessment following chest radiography, allowing direct visualization of diaphragmatic motion. 1
• Ultrasound chest has concordant findings with fluoroscopy for diaphragm motion assessment, with high sensitivity and specificity for neuromuscular disorders. 1

Critical Pitfalls to Avoid

Misdiagnosis Between Cardiac and Pulmonary Causes

• Emergency physicians identify only 36.8% of new-onset heart failure in patients with history of asthma or COPD presenting with dyspnea. 4
• The yield of adding routine BNP testing in patients with pulmonary disease history for detecting newly diagnosed heart failure is approximately 20%. 4
• Do not assume dyspnea is purely respiratory in patients with known lung disease—always consider cardiac contribution. 3, 4

Contraindications to Air Travel (If Relevant)

• Patients with current closed pneumothorax must avoid commercial air travel. 1, 6
• Patients with infectious tuberculosis must not travel until three smear-negative sputum examinations on separate days while on effective treatment. 1, 6
• Patients with recent major thoracic surgery should ideally delay flying for 6 weeks. 1, 6

Medication Considerations

• COPD is not a contraindication for beta-blockers in patients with concomitant heart failure; cardio-selective agents can be used if indicated. 3
• Concurrent heart failure and COPD reduce beta-blocker prescription threefold, resulting in only about 20% of patients being treated, which represents a major therapeutic gap. 3
• Beta-agonists in COPD/asthma are strongly associated with new heart failure (relative risk 3.41) and heart failure hospitalizations (odds ratio 1.74). 3

Risk Stratification

High-Risk Features Requiring Urgent Evaluation

• Resting oxygen saturation 92-95% with additional risk factors warrants hypoxic challenge testing. 1
• History of myocardial infarction with ventricular tachycardia concerns may require Holter monitoring and electrophysiologic study consideration. 1
• Screening for sleep-disordered breathing is reasonable in selected patients, as it is associated with greater symptom burden, reduced exercise capacity, increased atrial fibrillation prevalence, and worsens hypertension. 2