From the Guidelines
Echocardiogram is a recommended initial screening tool for diagnosing myocarditis, as it provides valuable information about heart function and structure, although it is not the definitive diagnostic tool. According to the most recent and highest quality study 1, a standard transthoracic echocardiogram should be performed in all patients with clinically suspected myocarditis. This non-invasive ultrasound test can detect decreased heart function, wall motion abnormalities, chamber enlargement, and pericardial effusion that may suggest myocarditis.
Key Findings of Echocardiogram in Myocarditis
- Decreased heart function (reduced ejection fraction)
- Wall motion abnormalities
- Chamber enlargement
- Pericardial effusion
However, echocardiogram findings are not specific to myocarditis alone, so additional tests are typically needed for a definitive diagnosis. These may include cardiac MRI (which can visualize inflammation directly) 1, blood tests for cardiac biomarkers (troponin, BNP), and in some cases, endomyocardial biopsy, which remains the gold standard for confirming myocarditis 1.
Limitations of Echocardiogram
- Lack of sensitivity and specificity to further characterize myocardial inflammation
- Nonspecific findings that may be useful for longitudinal studies
- May not distinguish between different myocarditis phenotypes
Despite these limitations, echocardiogram serves as an important initial screening tool that helps guide further diagnostic workup and treatment decisions for patients with suspected myocarditis. The American Heart Association recommends that a standard transthoracic echocardiogram should be performed in all patients with clinically suspected myocarditis 1.
Additional Diagnostic Tests
- Cardiac MRI
- Blood tests for cardiac biomarkers (troponin, BNP)
- Endomyocardial biopsy
In summary, while echocardiogram is not the definitive diagnostic tool for myocarditis, it is a valuable initial screening tool that provides important information about heart function and structure, and helps guide further diagnostic workup and treatment decisions. Echocardiogram should be used in conjunction with other diagnostic tests, such as cardiac MRI and endomyocardial biopsy, to confirm the diagnosis of myocarditis.
From the Research
Echocardiogram in Diagnosing Myocarditis
- Echocardiography is used as a primary tool to detect ventricular wall motion abnormalities, pericardial effusion, valvular regurgitation, and impaired function in suspected acute myocarditis 2.
- Transthoracic echocardiography (TTE) plays a key role in the initial work-up of myocarditis, where the identification of pathologic structural and functional changes may assist in its diagnosis and management 3.
- Echocardiographic parameters such as left ventricular (LV) size and systolic function, in particular LV end-diastolic diameter, LV ejection fraction (LVEF), and LV global longitudinal strain (LV-GLS), can reliably differentiate myocarditis from healthy controls 3.
- Myocardial deformation imaging by echocardiography is an evolving method used to characterize quantitatively longitudinal systolic function, which may be affected in acute myocarditis 4.
- Global longitudinal systolic myocardial strain correlated significantly with the amount of oedema in patients with acute myocarditis, making 2D speckle-tracking echocardiography a useful tool in the diagnostic process 4.
- Echocardiographic features of myocarditis are polymorphous and nonspecific, but in an appropriate clinical context, echocardiography can be helpful in the diagnosis of myocarditis and in the selection of patients for endomyocardial biopsy 5.
- The combination of echocardiography and emergency endomyocardial biopsy can lead to early decision making of intensive care, corticosteroids, and proper mechanical circulatory support prior to the possible sudden collapse in patients with myocarditis 6.
Key Echocardiographic Parameters
- Left ventricular (LV) size and systolic function
- LV end-diastolic diameter
- LV ejection fraction (LVEF)
- LV global longitudinal strain (LV-GLS)
- Global longitudinal systolic myocardial strain
Clinical Applications
- Initial work-up of suspected acute myocarditis
- Detection of ventricular wall motion abnormalities, pericardial effusion, valvular regurgitation, and impaired function
- Differentiation of myocarditis from healthy controls
- Selection of patients for endomyocardial biopsy
- Early decision making of intensive care, corticosteroids, and proper mechanical circulatory support in patients with myocarditis