Viral myocarditis—diagnosis, treatment options, and current controversies

Abstract

Myocarditis--a frequent cause of dilated cardiomyopathy and sudden cardiac death--typically results from cardiotropic viral infection followed by active inflammatory destruction of the myocardium. Characterization of this disease has been hampered by its heterogeneous clinical presentations and diverse aetiologies. Advances in cardiac MRI and molecular detection of viruses by endomyocardial biopsy have improved our ability to diagnose and understand the pathophysiological mechanisms of this elusive disease. However, therapeutic options are currently limited for both the acute and chronic phases of myocarditis. Several randomized, controlled trials have demonstrated potential benefit with immunosuppressive and immunomodulatory therapies, but further investigations are warranted. In this Review, we explore the pathophysiology, natural history, and modes of diagnosis of myocarditis, as well as evidence-based treatment strategies. As novel imaging techniques and human in vitro models of the disease emerge, the landscape of therapies for myocarditis is poised to improve.

The most common cause of sudden cardiac death in athletes

“…Usually, myocarditis is not accompanied by any symptoms, so SCD is the only manifestation of the disease. However, some patients may have evidence of viral infection, tachycardia, audible third heart sound, or gallop, an enlarged neck vein, peripheral edema and hepatomegaly, while on the chest X-ray observed cardiac enlargement (20). The most common abnormality in ECG seen in myocarditis is sinus tachycardia with non-specific ST segment and T wave changes (diffuse T wave inversion) (20).…”

“…However, some patients may have evidence of viral infection, tachycardia, audible third heart sound, or gallop, an enlarged neck vein, peripheral edema and hepatomegaly, while on the chest X-ray observed cardiac enlargement (20). The most common abnormality in ECG seen in myocarditis is sinus tachycardia with non-specific ST segment and T wave changes (diffuse T wave inversion) (20). Physical activity during the acute phase of the disease leads to an increase in viral replication, pronounced myocardial necrosis and increased risk of SCD.…”

“…Inflammation of the myocardium, lymphocyte infiltration and focal necrosis of tissue, which are determined on histopathological preparations, is a risk factor for electrical instability of the heart and the occurrence of arrhythmias (20). Usually, myocarditis is not accompanied by any symptoms, so SCD is the only manifestation of the disease.…”

“…Acute myocarditis is a rare but potentially dangerous disease, usually caused by viruses (in more than half of the cases by Coxsackie B virus, adenovirus and herpes viruses) (20). Inflammation of the myocardium, lymphocyte infiltration and focal necrosis of tissue, which are determined on histopathological preparations, is a risk factor for electrical instability of the heart and the occurrence of arrhythmias (20).…”

Reversible Dilated Cardiomyopathy: Into the Thaumaturgy of the Heart - Part 2

“…46 Myocarditis can be suspected clinically in symptomatic subjects [chest pain, pseudoischemic electrocardiographic (ECG) pattern, dyspnea, unexplained arrhythmias, cardiogenic shock] in the presence of one or 48 Extensive studies performed in biopsy and autopsy myocardial specimens have linked specific viral infections with up to 69% of cases of clinical myocarditis. 49 Moreover, elevated serum levels of antibodies against specific viruses have been detected in patients with idiopathic dilated cardiomyopathy.…”