| Popis: |
A major limitation of implantable defibrillators in the past has been the inability to document the arrhythmia precipitating discharge of the device. Although symptoms can be of some help in identifying the arrhythmia, symptomatic supraventricular arrhythmias and asymptomatic ventricular tachycardia (VT) have been documented in some cases before device discharge. The aim of this study was to systematically assess the value of stored intracardiac electrograms by implantable cardioverter-defibrillator in survivors of cardiac arrest during an antiarrhythmic drug free-period, in order to better define the arrhythmic profile determining device activation. The stored intracardiac electrograms of a fourth-generation cardioverter-defibrillator, implanted in 18 survivors of cardiac arrest were retrieved. The number of device activations, and the characteristics of any stored arrhythmic events were analyzed. A total number of 249 arrhythmic events were detected and stored over a mean follow-up of 378 +/- 107 days. These resulted in 78 delivered shocks, 84% of which were appropriate. Most of the detected events were episodes of unsustained VTs (33%), and atrial fibrillation or flutter (31%), which led to inappropriate shocks in 16% of the cases. The remaining recorded events were: sustained VT or fibrillation (66 episodes, 26%), sinus rhythm (11 events, 4%), not classified episode (6%). Of the 171 (69%) arrhythmic episodes not resulting in shocks, 73 events aborted before shock delivery by the device's reconfirmation algorithm, and the remaining 98 (39%) were detected but unsustained in duration, thus terminating before charging. In some cases, sustained and unsustained episodes of both supraventricular and ventricular arrhythmias gave symptoms.(ABSTRACT TRUNCATED AT 250 WORDS) |
