Cardiomyopathy: When the Heart Changes Shape. Signs, Diagnosis, and Treatment

What is cardiomyopathy?

Cardiomyopathy is a group of diseases of the myocardium (heart muscle) in which the heart loses the ability to effectively pump blood throughout the body. These conditions are characterized by structural and functional changes in the myocardium that are not related to coronary artery disease, hypertension, valvular defects, or congenital heart defects [7]. Cardiomyopathies can be primary (where myocardial damage is the primary disease) or secondary (developing against the background of other systemic diseases) [6, 7].

Regardless of the cause, cardiomyopathy often leads to serious complications such as heart failure, arrhythmias, and even sudden cardiac death [1, 7]. Understanding the different types of cardiomyopathies, their signs, and methods of diagnosis and treatment is crucial for improving patient prognosis.

Main types of cardiomyopathies

Cardiomyopathies are classified according to the nature of the changes in the heart muscle:

• Dilated cardiomyopathy (DCM): Characterized by the enlargement (dilation) of the heart chambers, especially the left ventricle, and a decrease in its contractile function [1]. This causes the heart to become weakened and unable to pump blood effectively. In children, DCM is the most common form of cardiomyopathy and one of the leading causes of heart failure and mortality [1]. Identified causes of DCM in children include myocarditis, genetic factors, and coarctation of the aorta [1]. An example of a specific etiology is Chagas disease – a chronic infection caused by the parasite Trypanosoma cruzi, which is a leading cause of non-ischemic heart failure in Latin America and is increasingly encountered worldwide due to migration [2]. The pathogenesis of Chagas disease is multifactorial and includes persistent parasitism, immune-mediated myocardial damage, and progressive fibrosis [2].
• Hypertrophic cardiomyopathy (HCM): This is the most common hereditary heart disease, characterized by thickening of the left ventricular walls, often asymmetrical [3, 5, 7]. The thickening can obstruct blood flow out of the heart (obstructive form) or impair its relaxation and filling (non-obstructive form) [4, 7]. HCM is a leading cause of heart failure and sudden cardiac death in young people [7]. It is important to differentiate HCM from other conditions that mimic it, such as amyloidosis or Fabry disease, which are called phenocopies [7].
• Atrial fibrillation-induced cardiomyopathy (AF-CMP): This is a secondary form of cardiomyopathy in which prolonged atrial fibrillation leads to left ventricular dysfunction. Notably, left ventricular function can recover after the restoration of sinus rhythm [6]. Studies show that myocardial degeneration, fibrosis, and cytoplasmic vacuolization are associated with delayed recovery of left ventricular function in AF-CMP [6].

Symptoms and signs of cardiomyopathy

Symptoms of cardiomyopathy can vary depending on its type and severity, but they are often associated with the development of heart failure or arrhythmias. Common signs include:

• Shortness of breath, especially during physical exertion or when lying down [1, 3].
• Increased fatigue and weakness [3].
• Swelling of the legs, ankles, and feet.
• Chest pain: in hypertrophic cardiomyopathy, chest pain is often associated with microvascular dysfunction, diastolic dysfunction, or left ventricular outflow tract obstruction. However, it can also mask concomitant coronary artery disease (CAD), which complicates diagnosis [4].
• Palpitations or a feeling of irregular heartbeats caused by arrhythmias, such as atrial fibrillation, which is the most frequent arrhythmia in HCM [5].
• Dizziness or fainting.
• Thromboembolic complications: in DCM, intracavitary thrombi can form [1], and in HCM with atrial fibrillation or atrial myopathy, the risk of thromboembolism increases significantly [5].

It is important to note that in children with dilated cardiomyopathy, all patients were symptomatic at the time of diagnosis [1]. Early detection of these symptoms and timely medical consultation are critical for preventing disease progression.

Diagnosis of cardiomyopathy: a comprehensive approach

Diagnosis of cardiomyopathy requires a structured and multidisciplinary approach, including various examination methods [7].

• Medical history and physical examination: The doctor evaluates symptoms, family history (especially if hereditary forms such as HCM are suspected), and performs a general examination.
• Electrocardiography (ECG): A routine method that can reveal signs of hypertrophy, arrhythmia, or myocardial ischemia [2, 4].
• Echocardiography (Echo): This is the cornerstone of heart assessment. It allows for the visualization of heart structure, measurement of chamber sizes and wall thickness, assessment of contractile function (ejection fraction), presence of valvular regurgitation (e.g., mitral regurgitation in DCM), and left ventricular outflow tract obstruction in HCM [1, 2, 4, 7]. Dynamic assessment using stress-Echo may be required to detect obstruction that only manifests during exertion [7].
• Cardiac magnetic resonance imaging (Cardiac MRI): Provides detailed images of the myocardium, allowing for precise measurement of wall thickness, assessment of fibrosis, and differentiation of various types of cardiomyopathies and their phenocopies [3, 4, 7]. Cardiac MRI can also predict the onset of new heart failure symptoms in patients with HCM [3].
• Computed tomography (CT) and coronary angiography: These methods are used to exclude coronary artery disease (CAD) as a cause of heart failure or a comorbid condition, especially in patients with chest pain [4, 8].
• Laboratory tests: Include complete blood counts, biochemistry, and specific tests, such as serological studies to confirm Trypanosoma cruzi infection when Chagas disease is suspected [2].
• Genetic testing: Recommended for hereditary forms of cardiomyopathy, such as HCM, to confirm the diagnosis, differentiate from phenocopies, and screen family members [7].
• Endomyocardial biopsy (EMB): In some cases, such as AF-CMP, a myocardial biopsy may be performed to assess histological features, such as fibrosis or myocardial degeneration [6].

Modern approaches to cardiomyopathy treatment

Treatment of cardiomyopathy is aimed at relieving symptoms, preventing disease progression, and improving the patient's quality of life and prognosis. The treatment approach is individualized and depends on the type of cardiomyopathy, its cause, and the presence of complications.

Drug therapy:

• Heart failure treatment: Includes drugs that improve heart function and reduce the load on it, such as ACE inhibitors, beta-blockers, diuretics, and mineralocorticoid receptor antagonists [2].
• Antiarrhythmic drugs: Prescribed to control arrhythmias, such as atrial fibrillation [2].
• Anticoagulants: In patients with HCM and atrial fibrillation, continuous anticoagulant therapy is indicated, regardless of the CHA2DS2-VA risk score [5]. Anticoagulants may also be necessary in the presence of intracavitary thrombi, which can form in DCM [1], or in atrial myopathy associated with an increased thromboembolic risk even during sinus rhythm [5].
• Specific therapy: For example, antiparasitic therapy for Chagas disease in the acute, congenital, or early chronic stage of infection [2].

Invasive and surgical methods:

• Catheter ablation: Can be performed to restore sinus rhythm in atrial fibrillation, especially in AF-CMP, which may lead to the recovery of left ventricular function [6].
• Device implantation: Installation of an implantable cardioverter-defibrillator (ICD) is recommended for the prevention of sudden cardiac death in high-risk patients [7]. In some cases, cardiac resynchronization therapy may be indicated.
• Surgical treatment: In obstructive HCM, myectomy (removal of a portion of the thickened heart muscle) can be performed to facilitate blood flow.
• Heart transplantation: Used in cases of terminal heart failure when other treatments are ineffective [2].

An important aspect is also genetic counseling and screening of family members for hereditary forms of cardiomyopathy [7]. Comprehensive management of patients with cardiomyopathy requires constant monitoring and dynamic observation for timely adjustment of therapy and prevention of complications.

Sources

1. [1] Dilated Cardiomyopathy in Children: A Diverse Etiological Profile. (Cureus, 2026) https://pubmed.ncbi.nlm.nih.gov/42306370/
2. [2] Chagas cardiomyopathy. (Heart (British Cardiac Society), 2026) https://pubmed.ncbi.nlm.nih.gov/42185038/
3. [3] Cardiac magnetic resonance imaging parameters predict new-onset symptoms of heart failure in hypertrophic cardiomyopathy. (ESC heart failure, 2026) https://pubmed.ncbi.nlm.nih.gov/42263198/
4. [4] Multimodality imaging in a patient with non-obstructive hypertrophic cardiomyopathy and multivessel coronary artery disease presenting with chest pain: a case report. (BMC cardiovascular disorders, 2026) https://pubmed.ncbi.nlm.nih.gov/42026489/
5. [5] New Insights in the Diagnosis and Treatment of Atrial Fibrillation in Patients with Hypertrophic Obstructive Cardiomyopathy. (Journal of clinical medicine, 2026) https://pubmed.ncbi.nlm.nih.gov/42074815/
6. [6] Association of Myocardial Degeneration With Delayed Recovery of Left Ventricular Function in Atrial Fibrillation-Induced Cardiomyopathy. (Circulation reports, 2026) https://pubmed.ncbi.nlm.nih.gov/42428634/
7. [7] Comprehensive evaluation of hypertrophic cardiomyopathy: European Journal of Heart Failure expert consensus document. (European journal of heart failure, 2026) https://pubmed.ncbi.nlm.nih.gov/41818712/
8. [8] Testing for Coronary Artery Disease in Patients Newly Diagnosed with Heart Failure in Alberta, Canada. (CJC open, 2026) https://pubmed.ncbi.nlm.nih.gov/41732584/

The information provided in this article is for reference purposes only and should not be used for self-diagnosis or self-treatment. Always consult a qualified medical professional for an accurate diagnosis and the prescription of appropriate treatment.