Angiology: Open Access
Open Access

Endomyocardial Biopsy and Imaging Techniques for the Diagnosis of Carditis: Current Approaches and Challenges

Ruth Feldman^{* *}Correspondence: Ruth Feldman, Department Clinical Cardiology, Alzahra University, Tehran, Iran, Email:

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Description

Carditis, which refers to inflammation of the heart muscle or its surrounding structures, is a serious condition that can lead to heart failure, arrhythmias, and sudden cardiac death if left undiagnosed and untreated. Myocarditis, a common form of carditis, often presents with nonspecific symptoms such as fatigue, chest pain, and palpitations, making its diagnosis challenging. Early detection and accurate diagnosis are critical for effective treatment and management. Traditionally, Endomyocardial Biopsy (EMB) has been considered the standard for diagnosing myocarditis, but with advancements in imaging techniques, there is an increasing transition toward non-invasive methods. This article examines the current approaches and challenges in diagnosing carditis using EMB and modern imaging technologies like Cardiac Magnetic Resonance imaging (CMR), Positron Emission Tomography (PET), and echocardiography, and evaluates their roles in clinical practice.

Endomyocardial biopsy

EMB has been the definitive diagnostic tool for myocarditis, allowing for direct histopathological analysis of myocardial tissue. The procedure involves inserting a catheter through the femoral or jugular vein into the heart to collect tissue samples from the myocardium, typically from the right ventricle. These samples are then examined for signs of inflammation, necrosis, and viral infections, and can be analyzed further through molecular techniques like Polymerase Chain Reaction (PCR) to identify specific pathogens such as viruses.

Advantages of EMB

The main advantage of EMB is that it provides direct evidence of myocardial inflammation and injury, provides a clear histological diagnosis. This is particularly important for differentiating between infectious myocarditis (due to viruses such as Coxsackievirus or adenovirus) and autoimmune myocarditis (such as giant cell myocarditis or sarcoid myocarditis), conditions that require distinct treatment strategies. Additionally, EMB can identify specific pathogens responsible for the inflammation, which is important for targeting antiviral or immunosuppressive therapies.

Advanced imaging techniques

The development of advanced cardiac imaging modalities has significantly improved the non-invasive diagnosis of myocarditis and other forms of carditis. CMR, PET, and echocardiography are the primary imaging techniques used to assess myocardial inflammation and other cardiac abnormalities.

Cardiac magnetic resonance imaging

CMR has emerged as one of the most powerful non-invasive tools for diagnosing myocarditis. It offers exceptional tissue characterization, allowing for the identification of areas of edema, necrosis, and fibrosis, which are indicative of myocardial inflammation. The use of gadolinium contrast agents helps detect delayed enhancement, a characteristic feature of myocardial injury, which is particularly useful in acute myocarditis. CMR is also highly sensitive in detecting myocardial edema, a key feature of active inflammation.

Advantages of CMR

CMR provides several advantages over EMB. It is non-invasive, reducing the risks associated with biopsy. Additionally, it provides comprehensive information not only about myocardial inflammation but also about cardiac function and structure, making it an invaluable tool for early diagnosis and follow-up. CMR’s ability to detect mild inflammation that may not be evident on routine imaging or clinical examination makes it ideal for early-stage disease, where early intervention can prevent long-term damage.

Echocardiography

Echocardiography remains one of the first-line imaging modalities for evaluating patients with suspected carditis. While it cannot directly visualize myocardial inflammation, it is extremely useful in identifying secondary effects of myocarditis, such as pericardial effusion, ventricular dysfunction, and abnormal wall motion. Transesophageal echocardiography is especially helpful in detecting infective endocarditis, a form of carditis.

Advantages of echocardiography

Echocardiography is widely available, non-invasive, and relatively inexpensive. It is particularly useful for assessing cardiac function and structural abnormalities, providing a real-time assessment of the heart’s performance. It also plays an important role in diagnosing complications associated with carditis, such as thrombus formation and valvular dysfunction.

Conclusion

While endomyocardial biopsy remains the remarkable standard for diagnosing myocarditis, it is invasive and not always feasible.

As a result, non-invasive imaging techniques, particularly CMR, PET, and echocardiography, have become integral to diagnosing carditis. CMR provides superior tissue characterization, PET is invaluable for assessing systemic inflammation, and echocardiography provides essential functional and structural information. The future of carditis diagnosis lies in combining these techniques to provide a comprehensive understanding of the disease. A personalized approach, guided by clinical symptoms, imaging findings, and biopsy when necessary, will likely be the most effective strategy for diagnosing and managing carditis in the modern era.