[Interventional treatment in patients with myocarditis: Pro and Contra]

Aim: Ventricular tachyarrhythmias (VTs) are often encountered in patients with inflammatory heart diseases. VT can become lifethreatening in patients with myocarditis, and the management may vary in different types of myocarditis. Purpose of the study is to describe VT characteristics in patients with verified myocarditis, and to evaluate the efficacy and safety of VT management, when tailored to the type of myocarditis.

Materials and methods: Study population comprised: 56 patients with morphologically verified myocarditis; 18 patients with primary cardiomyopathy (control group). All patients underwent full clinical evaluation, endomyocardial biopsy (including immunohistochemical analysis). Forty (54 %) patients underwent radiofrequency catheter ablation of VT. An implantable cardioverter-defibrillator (ICD) was inserted in 17 patients.

Results: There was no statistically significant difference between myocarditis and primary cardiomyopathy groups by demographic and echocardiographic data. In myocarditis group, nonsustained VT and/or frequent premature ventricular beats were seen in 59 % of patients; sustained VT in 12,5 % subjects, 1 patient had a history of ventricular fibrillation. VT ablation was associated with a significant decrease in VT recurrence (p=0,0009) during the follow-up period. Active myocarditis was associated with a higher VT recurrence rate (67 % in active vs. 19 % in borderline myocarditis). Among patients with ICD implantation, only one subject (with active myocarditis at admission) had life-threatening ventricular arrhythmia.

Conclusion: In this selected group of patients with verified myocarditis and clinically significant VTs, catheter ablation seems at least partly effective. Patients with borderline myocarditis and symptomatic VTs may benefit from ablation. Therefore, morphological diagnostic of myocarditis can be a key point in choice of treatment.