Evolution of Clinical Practices in the Diagnosis and Management of Acute Myocarditis

Simon Majer^*
*Correspondence: Simon Majer, Department of Cardiology, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia, Tel: smajer@gmail.com,

Introduction

Acute myocarditis is an inflammatory condition of the heart muscle, often resulting from viral infections, autoimmune diseases, or exposure to toxins. It presents a significant clinical challenge due to its diverse etiology and variable clinical manifestations. The condition can lead to severe complications, including heart failure, arrhythmias and sudden cardiac death, making early diagnosis and effective management crucial. Historically, the understanding and management of myocarditis have evolved significantly. Early descriptions date back to the 19th century, but it wasn't until the 20th century that advancements in medical technology and research began to shed light on its pathophysiology and clinical implications. Initially, myocarditis was often underdiagnosed or misdiagnosed due to its nonspecific symptoms and lack of definitive diagnostic tools. The evolution of clinical practices in diagnosing and managing acute myocarditis reflects broader trends in medical science, including advancements in imaging technologies, biomarker discovery and therapeutic interventions. Understanding this evolution is essential for clinicians to provide optimal care and for researchers to identify areas requiring further investigation [1].

Description

In the early 20th century, the diagnosis of myocarditis was primarily based on clinical symptoms and post-mortem examinations. The advent of Electro Cardio Graphy (ECG) in the 1920s provided a non-invasive method to assess cardiac electrical activity, aiding in the identification of myocardial involvement. However, the sensitivity and specificity of ECG in detecting myocarditis remained limited. The development of echocardiography in the 1950s allowed for real-time visualization of cardiac structures and function. This advancement enabled clinicians to detect signs of myocardial inflammation and assess ventricular function more accurately. Later, the introduction of Magnetic Resonance Imaging (MRI) in the 1980s revolutionized the non-invasive assessment of myocarditis, offering detailed images of myocardial tissue and the ability to detect inflammation and edema. The identification of specific biomarkers associated with myocardial injury, such as troponins and B-type Natriuretic Peptide (BNP), provided clinicians with tools to assess the extent of myocardial damage. These biomarkers, when used in conjunction with imaging studies, enhanced the accuracy of acute myocarditis diagnosis [2].

Patients with acute myocarditis may present with a range of symptoms, from mild fatigue and chest discomfort to severe heart failure and arrhythmias. The variability in presentation poses a challenge for early diagnosis, emphasizing the need for a high index of suspicion. ECG remains a fundamental tool in the initial assessment of suspected myocarditis. Characteristic findings may include ST-segment elevation, T-wave inversions and conduction abnormalities. However, these findings are not pathognomonic and must be interpreted in conjunction with other diagnostic modalities. Cardiac Magnetic Resonance imaging (CMR) has become the gold standard for non-invasive assessment of myocarditis. The Lake Louise Criteria, established in 2018, provide a standardized approach to interpreting CMR findings, focusing on myocardial edema, hyperemia and necrosis. CMR's high spatial resolution allows for detailed evaluation of myocardial tissue, aiding in the diagnosis and assessment of disease severity [3].

Endomyocardial biopsy, though invasive, remains the definitive method for diagnosing myocarditis. It allows for histological examination of myocardial tissue, identifying inflammatory infiltrates and viral genomes. However, its use is limited by procedural risks and sampling errors, making it less commonly employed in routine clinical practice. The role of biomarkers in diagnosing acute myocarditis continues to evolve. Elevated levels of cardiac troponins indicate myocardial injury, while BNP levels can reflect the degree of heart failure. Research into other potential biomarkers, such as high-sensitivity C-Reactive Protein (hs-CRP) and interleukins, is ongoing to improve diagnostic accuracy and prognostication. Initial management of acute myocarditis focuses on supportive care, including the use of diuretics, angiotensin-converting enzyme inhibitors and beta-blockers to manage heart failure symptoms. The goal is to stabilize the patient and prevent further myocardial damage [4].

In cases where autoimmune processes are implicated, immunosuppressive therapies such as corticosteroids and Intra Venous Immune Globulin (IVIG) may be considered. However, the efficacy of these treatments remains a topic of debate, with some studies suggesting limited benefit and potential risks. For myocarditis suspected to be of viral etiology, antiviral medications may be employed. The effectiveness of this approach depends on the specific virus involved and the timing of treatment initiation. Early intervention is crucial, but the role of antiviral therapy in improving outcomes is still under investigation. In severe cases of acute myocarditis leading to refractory heart failure, mechanical circulatory support devices, such as intra-aortic balloon pumps and ventricular assist devices, may be necessary. These interventions provide temporary support while awaiting recovery or heart transplantation. For patients with end-stage heart failure unresponsive to medical therapy, heart transplantation remains the definitive treatment option. The decision to proceed with transplantation is complex, involving considerations of patient age, comorbidities and overall prognosis. Despite advancements in diagnostic modalities, challenges persist in accurately diagnosing acute myocarditis. The variability in clinical presentation, overlap with other cardiac conditions and limitations of current diagnostic tools contribute to delays in diagnosis and treatment. The optimal management of acute myocarditis remains uncertain, with ongoing debates regarding the use of immunosuppressive and antiviral therapies. The lack of large-scale, randomized controlled trials limits the ability to establish definitive treatment protocols. Identifying reliable prognostic indicators is crucial for guiding treatment decisions and predicting outcomes. While certain clinical and laboratory findings may offer insights, no single factor has proven to be consistently predictive of disease course [5].

Conclusion

The evolution of clinical practices in the diagnosis and management of acute myocarditis reflects significant advancements in medical science and technology. While challenges remain, ongoing research and innovation continue to improve patient outcomes. A multidisciplinary approach, incorporating advancements in imaging, biomarker discovery and therapeutic interventions, is essential for optimizing care for patients with acute myocarditis. Continued efforts are needed to refine diagnostic criteria, develop targeted therapies and establish comprehensive management protocols. Collaborative research and clinical trials will be instrumental in addressing existing gaps in knowledge and ensuring that patients receive the most effective and personalized care possible. In summary, the journey from early recognition to contemporary management of acute myocarditis underscores the dynamic nature of medical practice and the importance of continuous learning and adaptation in the face of evolving clinical challenges.

Acknowledgement

None.

Conflict of Interest

None.

References

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