[Frequent unifocal ventricular premature contractions that caused dilated cardiomyopathy: resolution of myocardial function after successful catheter-ablation of arrhythmia focus].

Introduction: In patients with dilated cardiomyopathy (DCM) and frequent ventricular premature beats (VPBs) it may be difficult to evaluate whether ventricular arrhythmia is the cause or consequence of heart failure. However, it is very important to recognize VPBs as a potentially reversible cause of myocardial dysfunction, because arrhythmia suppression in these patients may lead to recovery of myocardial contractility.

Case Outline: An asymptomatic 24-year-old man with DCM and frequent VPBs of left bundle branch morphology with inferior axis was referred to our Department for further evaluation. Echocardiographic examination showed left ventricular dilation with reduced ejection fraction to 40%, while 24 h Holter-monitoring recorded 31,000 isolated VPBs refractory to drug treatment. During the electrophysiologic study a VPBs' focus in the right ventricular outflow tract was identified which was successfully resolved by radiofrequency catheter-ablation. Immediately after the procedure, considerable suppression of VES number to 2500/24 h was confirmed by Holter-recording, while complete recovery of left ventricular function was detected one month later by echocardiographic re-examination.

Conclusion: Recognition of causal-resultant relation between frequent VPBs and progressive myocardial dysfunction is of primary importance for adequate treatment. Although it has been believed for a long time that idiopathic ventricular arrhythmia, in otherwise healthy persons, has a benign prognosis, there is evidence that frequent VPBs may present a reversible cause of DCM. In these patients catheter-ablation of arrhythmic focus is strongly recommended, because soon after the successful procedure recovery of myocardial function can be expected.