COPD Diagnosis

Diagnostic challenges in concomitant CHF

Recognizing the disease in patients suffering from chronic heart failure (CHF) represents a major clinical problem. These difficulties are due to the similarity of the clinical presentation: dyspnea, decreased exercise tolerance, and cough can be manifestations of either pathology.

Furthermore, the presence of heart failure complicates the interpretation of spirometry results, which is one of the main reasons for the overdiagnosis of both chronic obstructive pulmonary disease and bronchial asthma in this group of patients.

In clinical practice, it is often necessary to perform a differential diagnosis of cough. If a cough appears or worsens in a patient with cardiopulmonary pathology, the physician must sequentially rule out three conditions:

1. Exacerbation of the bronchoobstructive process.
2. Decompensation of heart failure.
3. Intolerance to angiotensin-converting enzyme (ACE) inhibitors, for which cough is a frequent side effect.

Differential diagnosis with bronchial asthma

A key task in establishing a diagnosis is distinguishing the pathology from bronchial asthma (BA). The diagnosis of BA is established comprehensively, taking into account complaints, allergic status, and mandatory spirometry with a bronchodilator test (for patients over 5 years of age).

The main differences between the diseases:

• Nature of obstruction: In BA, the obstruction is reversible, whereas in COPD it is irreversible.
• Type of inflammation: Asthma is typically characterized by eosinophilic inflammation (which can be detected in blood or sputum laboratory tests), as well as bronchial hyperreactivity. In COPD, inflammatory infiltration is represented by neutrophils (polymorphonuclear leukocytes).
• Response to therapy: Asthma patients demonstrate a pronounced positive response to bronchodilators and steroid therapy (the effect of trial therapy with inhaled glucocorticosteroids). In COPD, the effect of these drug groups is minimal or completely absent.
• Anatomy of the lesion: Chronic obstruction affects the entire bronchial tree, including the smallest branches—bronchioles, and is very frequently combined with acinar involvement (emphysema). Asthma is characterized by fluctuating symptoms, often debuts at a young age, and is associated with a burdened heredity.

Important note: normal pulmonary function test values during the intercritical period do not rule out a diagnosis of asthma, whereas normalization of values is uncharacteristic for chronic obstructive pulmonary disease.

Management of comorbid patients: use of beta-blockers

The presence of chronic bronchoobstruction is not a contraindication for prescribing $\beta$-blockers to patients with heart failure.

According to guidelines (Level of Evidence A, Class of Recommendation 1), patients with a combination of these two diseases are indicated exclusively cardioselective $\beta$-blockers. These include:

• Bisoprolol;
• Metoprolol (in prolonged-release or extended-action tablet forms);
• Nebivolol.

This choice is justified by the fact that these specific drugs carry a significantly lower risk of developing adverse bronchoobstruction. Nevertheless, the initial prescription and subsequent titration (gradual dose increase) of cardioselective drugs must be carried out under strict and constant medical supervision.

Class and exam questions

What else to study on this topic

• Relationship between chronic bronchitis and emphysema
• Chronic diffuse lung diseases (CDLD)
• Atopic (exogenous) and non-atopic bronchial asthma
• Pathogenesis of bronchial asthma
• Churg-Strauss syndrome

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.