Arrhythmias in acute pericarditis - An endomyocardial biopsy study

It is still controversial whether the arrhythmias in acute pericarditis are of myocardial or pericardial origin. The aim of the present study was to i nvestigate the occurrence of arrhythmias and conduction disorders in patien ts with acute pericarditis with no endomyocardial biopsy evidence of myocar ditis (group 1: 40 patients, 65% males, mean age 45.6 +/- 15.7 years, mean heart rate [HR] 98.7 +/- 22.2 beats per minute) in comparison to endomyocar dial biopsy proven acute myocarditis/perimyocarditis (group 2: 10 patients, 3/10 with perimyocarditis, 70% males, mean age 46.1 +/- 15.8 years, mean h eart rate 76.7 +/- 33.1 beats per minute). At the initial assessment all pa tients underwent comprehensive clinical work-up including echocardiography, cardiac catheterization, and endomyocardial biopsy. In all patients bivent ricular endomyocardial biopsy was performed using standard femoral approach and Schikumed 7 F or 8 F bioptomes. Tissue samples were stained by H & E, v. Gieson and independently reviewed by two cardiac pathologists. In additi on immunohistochemistry and immunocytochemistry were performed, and only pa tients fulfilling Dallas and World Heart Federation criteria were selected for group 2. Comparative analysis of electrocardiograms and 24-hour Holter recordings at initial presentation revealed in group 1 vs group 2 significantly less fre quent paroxysmal supraventricular tachyarrhythmias (5% vs 40%), and ventric ular fibrillation (0 vs 20%), in contrast to atrial fibrillation that occur red more often (20% vs 0) (all p < 0.05). Furthermore, in the group 2 one p atient died due to VF and two patients underwent ICD implantation. Low volt age (40% vs 30%) and ST/T wave changes (47.5% vs 30%), as well as the incid ence of the II<degrees> AV block (5% vs 0) and complete AV block (2.5% vs 1 0%) were not significantly different between the groups. In conclusion, patients with pericarditis and no endomyocardial biopsy indi cations of myocarditis had significantly less often life threatening rhythm disorders in contrast to patients with endomyocardial biopsy proven acute myocarditis/perimyocarditis. On the contrary, incidence of transitory atria l fibrillation was higher in acute pericarditis, than in myocarditis.