Inflammatory left ventricular microaneurysms as a cause of apparently idiopathic ventricular tachyarrhythmias

Background-We sought to investigate the arrhythmogenic role, incidence, tre atment, and prognosis of inflammatory left ventricular (LV) microaneurysms in patients with apparently idiopathic ventricular tachyarrhythmias. Methods and Results-We studied 156 consecutive patients (71 men, 85 women; mean age, 44.1 +/- 11.8 years) with severe ventricular arrhythmias and norm al 2D echo cardiac parameters by coronary and ventricular angiography, bive ntricular endomyocardial biopsy, and electrophysiological study. Polymerase chain reaction was used to detect genomic sequences of enterovirus, adenov irus, Epstein Barr virus, cytomegalovirus, herpes simplex viruses, influenz a A and B viruses, and hepatitis C virus in frozen endomyocardial samples. Of these patients, 15 (9.6%) showed angiographic evidence of single or mult iple LV microaneurysms. All 15 patients had recurrent episodes of ventricul ar tachycardia with right bundle-branch block morphology, and the arrhythmi as originated within or close to the aneurysms in those patients (n=6) unde rgoing ventricular mapping. A lymphocytic myocarditis was observed in LV bi opsies of all patients and in the right ventricles of 3 patients. Polymeras e chain reaction analysis was performed in 12 and Viral genomes were found in 5 (42%): hepatitis C virus in 2, enterovirus in 2, and influenza virus A in 1. The patients were treated with antiarrhythmics, and cardiac function was preserved for the next 47 +/- 39.5 months of follow-up. No major clini cal event was registered, and arrhythmias were successfully treated by anti arrhythmics. Conclusions-Inflammatory LV microaneurysms, often of viral origin, are a co nsistent cause of apparently idiopathic ventricular arrhythmias. Their prog nosis so far has been benign, and aggressive therapeutic strategies have be en unnecessary.