[Atrial lead placement in the right atrial appendage during recent or chronic arrhythmia].

An atrial arrhythmia could be encountered during the atrial lead implantation. The lead placement must subsequently be delayed after restitution of the sinus rhythm or completely abandoned. The authors investigate the atrial lead placement during atrial arrhythmia and the lead performance at 6-month follow-up. The study population was 65 patients aged 78.5 years, 42 males and 28 structural heart diseases. They were implanted for sick sinus syndrome (n=14), atrioventricular block (n=44), infra-hisian conduction abnormality (n=7) in association with an atrial fibrillation (63.1%), an atrial flutter (24.6%) or an atrial tachycardia (12.3%). The onset of the arrhythmia was < or = 7 days (47.7%) or > 7 days (52.3%). An atrial lead was placed in the right atrial appendage under fluoroscopic control. If the sinus rhythm was not restored at 1 month, an electrical cardioversion was performed. The per-implantation atrial signal amplitude was 2.2+/-1.5 mV (range 0.5 mV to 7 mV). Sinus rhythm was restored in 54 patients. At 1 month, one patient was in an incessant atrial fibrillation. The 53 patients in sinus rhythm had a good atrial lead performance. Out of 46 patients who completed the 6-month follow-up, 4 had an arrhythmia recurrence. The 42 patients in sinus rhythm had a good atrial lead performance. At 1 and 6-month follow-up, the atrial pacing threshold (1.1+/-0.7 V vs 1.2+/-1.0 V, ns) and the atrial signal amplitude (2.1+/-1.0 mV and 2.1+/-0.9 mV, ns) were stable. Comparing the patients with a recent or a chronic arrhythmia, the pacing thresholds (1.2+/-1.1 V vs 1.14+/-0.8 V, ns), the atrial signal amplitudes (2.17+/-0.9 mV vs 2.05+/-0.9 mV, ns) and the proportion of satisfactory pacemaker performance in DDD(R) mode for the patients in sinus rhythm (100% vs 100%, ns) did not statistically differ between the two groups at 6 months. In conclusion, the placement of an atrial lead in the right atrial appendage during an atrial arrhythmia is feasible with a good lead performance at 6 months in sinus rhythm regardless the onset time of the arrhythmia and provides a satisfactory atrial-based pacing with the preservation of the atrioventricular synchrony.