From the Guidelines
The workup for cardiomyopathy involves a comprehensive evaluation, including a thorough medical history and physical examination, as well as diagnostic testing, as emphasized by the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines 1.
Key Components of the Workup
- Initial laboratory tests: complete blood count, basic metabolic panel, liver function tests, and thyroid function tests, as well as measurement of serum troponin and B-type natriuretic peptide (BNP) levels.
- Echocardiography: the primary imaging modality, which may be supplemented by cardiac magnetic resonance imaging (MRI) or computed tomography (CT) angiography to assess cardiac structure and function, as recommended by the European Association of Cardiovascular Imaging 2 and the American Heart Association 3.
- Family history: a 3-generational family history should be obtained to aid in establishing the diagnosis of familial dilated cardiomyopathy, as suggested by the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines 1.
- Imaging techniques: should be used to answer a specific clinical question, and may include cardiac magnetic resonance (CMR) to assess cardiac anatomy, ventricular function, and the extent of myocardial fibrosis, as well as cardiac-computed tomography (CT) to exclude significant epicardial coronary artery disease, as recommended by the European Association of Cardiovascular Imaging 2 and the American Heart Association 4.
Medications and Management
Medications such as metoprolol succinate (25-200mg daily) and lisinopril (2.5-40mg daily) may be initiated to manage symptoms and slow disease progression, with dosages titrated based on individual patient response and tolerance. The workup and management of cardiomyopathy should be individualized based on the specific type and severity of the disease, as well as the patient's overall health status and medical history, as emphasized by the American Heart Association 3 and the European Association of Cardiovascular Imaging 2.
From the Research
Diagnostic Workup for Cardiomyopathy
The diagnostic workup for cardiomyopathy involves a combination of imaging modalities and electrocardiographic findings.
- The first-line diagnostic tool is the electrocardiogram (ECG), which can raise suspicion of cardiomyopathy and identify diagnostic "red flags" useful for orienting the diagnosis toward specific forms 5.
- Echocardiography is the first modality of choice for the evaluation of cardiomyopathies, and can be used to narrow the differential diagnosis using cardiac magnetic resonance (CMR) and nuclear imaging techniques 6.
- CMR has emerged as a powerful tool complementary to echocardiography to confirm diagnosis, provide prognostic information, and guide therapeutic strategies, particularly in the pediatric population 7.
- In the evaluation of dilated cardiomyopathy, multiple imaging modalities play a fundamental role in recognizing the underlying pathological substrate, including echocardiography, CMR, and nuclear images 8.
- For hypertrophic cardiomyopathy, CMR has become the gold standard imaging modality, providing higher image quality, spatial resolution, and identification of morphological variants 9.
Imaging Modalities
The following imaging modalities are used in the diagnostic workup for cardiomyopathy:
- Echocardiography: first modality of choice, allows identification of associated cardiac abnormalities and features associated with adverse prognosis 6, 8.
- Cardiac magnetic resonance (CMR): provides accurate and reproducible assessment of ventricular volumes and ejection fraction, and allows tissue characterization 6, 7, 8, 9.
- Nuclear imaging: useful for identifying specific causes of left ventricular dysfunction, such as cardiac sarcoidosis and amyloidosis 6, 8.
- Electrocardiogram (ECG): first-line diagnostic tool, can raise suspicion of cardiomyopathy and identify diagnostic "red flags" 5.
Specific Cardiomyopathies
The diagnostic workup may vary depending on the specific type of cardiomyopathy:
- Arrhythmogenic cardiomyopathy of the right ventricle (ARVC): ECG findings such as inverted T waves in right precordial leads (V1-V3) or beyond can be diagnostic 5.
- Cardiac amyloidosis: ECG findings such as low voltages, and imaging findings such as late gadolinium enhancement on CMR can be diagnostic 5, 6.
- Hypertrophic cardiomyopathy (HCM): CMR is the gold standard imaging modality, providing higher image quality and spatial resolution 9.