Acute Lymphocytic Myocarditis Complicated By Bidirectional Ventricular Tachycardia Treated With Early Steroid Use.

Acute lymphocytic myocarditis can precipitate malignant ventricular arrhythmias, including the rare presentation of bidirectional ventricular tachycardia (BDVT), a rhythm associated with significant hemodynamic instability. Although BDVT is classically linked to catecholaminergic polymorphic ventricular tachycardia and digitalis toxicity, it is increasingly recognized in myocarditis, likely reflecting diffuse inflammatory involvement of the myocardium and Purkinje system. Emerging evidence suggests that early corticosteroid therapy may rapidly reduce arrhythmia burden and improve ventricular function in selected patients with active myocardial inflammation. We report the case of a 34-year-old woman who presented with palpitations and syncope and was found to have BDVT secondary to acute lymphocytic myocarditis. Despite typical medical management, she had refractory ventricular arrhythmias. Prompt initiation of corticosteroids led to marked suppression of arrhythmias and rapid recovery of left ventricular ejection fraction. While current data remain limited, this case supports the potential benefit of early immunosuppressive therapy when active lymphocytic inflammation is strongly suspected.