Corticosteroid therapy for ventricular tachycardia in children with silent lymphocytic myocarditis.
OBJECTIVE
The objective of our study was to describe the efficacy of corticosteroids for ventricular tachycardia in four children with structurally normal hearts in whom endomyocardial biopsy revealed histologic changes of lymphocytic myocarditis.


METHODS
The four patients had unexplained ventricular tachycardia. Three dysrhythmias were sustained, and one was inducible by exercise. Patient ages ranged from 4 months to 12 years. Three of the four patients had no symptoms. In two of them, ventricular tachycardia was identified by mass screening for heart disease. Two patients received oral steroids and two received pulse steroid therapy.


RESULTS
In all four patients, significant underlying diseases were not found by noninvasive evaluation. Right ventricular endomyocardial biopsy revealed abnormal histologic findings of chronic lymphocytic myocarditis in all patients. Steroid therapy was effective in all four patients, two of whom received methylprednisolone pulse therapy.


CONCLUSIONS
We conclude that unexplained ventricular tachycardia may be the only manifestation of clinically silent myocarditis. Steroid therapy should therefore be considered if conventional antiarrhythmic medication is not effective and histologic findings confirm the presence of lymphocytic myocarditis.
Department of Pediatrics, Juntendo University School of Medicine, Tokyo, Japan.
T
T
Ino
M
M
Okubo
K
K
Akimoto
K
K
Nishimoto
K
K
Yabuta
S
S
Kawai
R
R
Okada
D000293:Adolescent; D001706:Biopsy; D006328:Cardiac Catheterization; D002648:Child; D002675:Child, Preschool; D004699:Endocardium / Q000473:pathology; D005260:Female; D006801:Humans; D007223:Infant; D008214:Lymphocytes / Q000473:pathology; D008297:Male; D008775:Methylprednisolone / Q000008:administration & dosage*; D009205:Myocarditis / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D011239:Prednisolone / Q000008:administration & dosage*; D012074:Remission Induction; D017180:Tachycardia, Ventricular / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology
D011239:Prednisolone; D008775:Methylprednisolone