Eosinophilic Myocarditis: Diagnosis, Treatment and Innovations

Jayme Castro^*
*Correspondence: Dr. Jayme Castro, Department of Cardiology, University of Bangkok, Bangkok, Thailand, Email:

Description

Eosinophilic myocarditis is a rare and often underdiagnosed inflammatory condition of the heart characterized by the infiltration of eosinophils into the myocardium. Despite its infrequency, eosinophilic myocarditis can lead to significant morbidity and mortality, necessitating a deeper understanding of its etiology, clinical presentation, diagnostic challenges, and evolving treatment approaches. Eosinophilic myocarditis remains an enigmatic entity within the spectrum of cardiac disorders. Eosinophils, a type of white blood cell, are typically involved in immune responses against parasites and allergic reactions. However, when these cells infiltrate the myocardium, the consequences can be severe and may include myocardial damage, heart failure, and life-threatening arrhythmias.

The underlying causes of eosinophilic myocarditis are diverse. Hypereosinophilic syndromes, autoimmune diseases, infections, and certain medications have been implicated in triggering the immune response leading to eosinophil infiltration in the heart. The challenge lies in recognizing the condition, as its clinical manifestations can mimic those of other heart diseases [1]. Eosinophilic myocarditis presents a wide spectrum of clinical manifestations, ranging from subtle symptoms to life-threatening events. Patients may experience chest pain, shortness of breath, fatigue, and palpitations. The variability in symptoms often leads to misdiagnosis or delayed recognition of the condition [2].

In severe cases, eosinophilic infiltration can cause myocardial damage, leading to heart failure. Additionally, the deposition of eosinophils can disrupt the normal electrical conduction system of the heart, resulting in arrhythmias. Cardiogenic shock and sudden cardiac death may occur in extreme cases, underscoring the importance of early diagnosis and intervention. The diagnosis of eosinophilic myocarditis poses significant challenges due to its rarity and the diverse array of potential causes. Clinicians must maintain a high index of suspicion, particularly in patients with unexplained heart failure, persistent chest pain, or refractory arrhythmias [3]. A detailed medical history, including information about allergies, recent infections, and medication use, is crucial in identifying potential triggers.

Laboratory tests play a role in detecting eosinophilia, an elevated level of eosinophils in the blood. However, eosinophilic myocarditis can occur without marked peripheral eosinophilia, making it imperative to consider the overall clinical picture. Imaging studies, such as echocardiography and cardiac magnetic resonance imaging, can reveal characteristic findings, including myocardial wall thickening, eosinophilic infiltrates, and evidence of myocardial inflammation [4]. Endomyocardial biopsy remains the gold standard for confirming the diagnosis of eosinophilic myocarditis. However, the decision to pursue biopsy is often challenging, considering the invasive nature of the procedure and the potential for sampling errors. Furthermore, eosinophilic myocarditis can be patchy, making it difficult to capture affected areas during biopsy.

The management of eosinophilic myocarditis is complex and requires a multifaceted approach. The underlying cause, if identified, should be addressed, whether it be an autoimmune disorder, infection, or medication-related. In cases where hypereosinophilic syndromes are implicated, immunosuppressive therapy may be employed to modulate the immune response. Corticosteroids are a cornerstone of treatment for eosinophilic myocarditis, aiming to reduce inflammation and eosinophil infiltration. However, the optimal duration and dosage of corticosteroid therapy remain areas of ongoing research and debate. In refractory cases or those with severe heart failure, additional immunomodulatory agents may be considered. Interleukin-5 inhibitors, such as mepolizumab, have shown promise in reducing eosinophil counts and improving cardiac function in some patients [5]. These targeted therapies represent a paradigm shift in the management of eosinophilic disorders, offering more specific and potentially safer options compared to broad immunosuppression.

The prognosis of eosinophilic myocarditis varies widely based on the severity of myocardial involvement and the underlying cause. Timely and appropriate treatment can lead to improvement in cardiac function and overall outcomes. However, delayed diagnosis or inadequate treatment may result in progressive myocardial damage and irreversible heart failure. Long-term considerations for individuals with eosinophilic myocarditis include close monitoring of cardiac function, ongoing immunosuppressive therapy if indicated, and addressing potential triggers or underlying conditions. Regular follow-up with a multidisciplinary team, including cardiologists, immunologists, and other specialists, is crucial for comprehensive care.

The rarity of eosinophilic myocarditis underscores the importance of awareness among healthcare providers. Increased recognition of the condition and its potential triggers can contribute to earlier diagnosis and intervention, improving outcomes for affected individuals. Research in the field of eosinophilic disorders is essential for advancing our understanding of the pathophysiology, refining diagnostic criteria, and exploring novel therapeutic options. Collaboration between clinicians, researchers, and advocacy groups is crucial in promoting awareness and supporting ongoing efforts to unravel the complexities of eosinophilic myocarditis.

Eosinophilic myocarditis, though rare, represents a significant challenge in the realm of cardiovascular medicine. Its elusive nature, diverse clinical manifestations, and potential for severe complications necessitate a heightened awareness among healthcare providers. By understanding the complexities of eosinophilic myocarditis, advancing diagnostic approaches, and exploring innovative treatment modalities, we can strive towards better outcomes for individuals affected by this underdiagnosed cardiac disorder. Ongoing research and collaborative efforts are crucial in unraveling the enigma of eosinophilic myocarditis and improving the lives of those living with this challenging condition.

References

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