IMMUNOSUPPRESSIVE TREATMENT FOR MYOCARDITIS AND BORDERLINE MYOCARDITIS IN CHILDREN WITH VENTRICULAR ECTOPIC RHYTHM

Objectives-To ascertain the responsiveness to immunosuppressive treatm ent of myocarditis and borderline myocarditis in children with ventric ular ectopic rhythm (that is, all ventricular arrhythmia except benign premature ventricular contractions). To determine the impact of the d iagnostic information provided by an endomyocardial biopsy specimen in these patients. Background-The therapeutic value of performing an end omyocardial biopsy in children with ventricular ectopic rhythm is not established. In turn, the treatment of myocarditis with immunosuppress ive drugs is also controversial. Methods-The case notes and endomyocar dial biopsy findings of all children with ventricular ectopic rhythm a nd a biopsy diagnosis of myocarditis were reviewed. Results-Ten (14%) of 69 patients with ventricular ectopic rhythm and an anatomically nor mal heart had histological evidence of myocarditis or borderline myoca rditis. Eight patients received corticosteroids and efficacy was judge d by regular 24 hour Holter monitoring. Total resolution of arrhythmia was seen in four, improvement in two, and no change in two patients. At follow up (8-39 months, mean 22 months), arrhythmia recurrence was seen in the two patients who showed an improvement but not resolution during treatment. Both received azathioprine with further reduction in ectopy rates. Patients who responded to treatment were symptomatic (s ix of six patients) at presentation compared respond to patients) who were not symptomatic. Five patients had a repeat biopsy specimen taken which confirmed histological improvement. Conclusions-Steroid treatme nt seems to benefit a subset of children with ventricular ectopic rhyt hm and a biopsy diagnosis of myocarditis or borderline myocarditis. Be cause it can identify a treatable cause for the ventricular arrhythmia , endomyocardial biopsy is a valuable investigation in these patients.