The mechanism of reentry was not correlated with the risk of stroke: 68% of the patients with strokeand70%ofthepatientswithoutstroke(NS) had typical AVRT; 10.5% of the patients with stroke and 18.5% of the patients without stroke had a concealed AP (NS); patients with stroke tended to have more frequently an atypical AVRT (21%) than the patients without stroke (11%), but the differences were not significant (Table II).