Surgical approach for right heart bypass in patients with isomeric atrial appendages

pp 391-397

Abstract

Epicardical mapping was performed during operation in 44 patients with isomerism of the rightatrial appendages and 23 with left isomerism. Marked diversity was found in the site of earliestactivation. It was frequently located at the junction of atrium and the superior caval vein in thesetting of right isomerism (33 out of 44), while an inferior site of activation at the junction of theatrium and inferior caval vein or a hepatic vein was relatively common in left isomerism (12 outof 23). In 6 of right (13%) and 3 of left (14%) isomerism, additional sites of earliest activation weredetected when the dominant site was suppressed. The earliest site of atrial activation observed byepicardial mapping did not necessarily accord with those expected from the preoperative evaluations nor with previous histological findings. The sites for the electrophysiologically recorded pacemakers, as well as the established location for the anatomically sinus nodes, were carefully avoided at both the initial atriotomy and subsequent intra atrial manoeuvres. Sinus rhythm was preserved postoperatively in all patients. Significant supraventricular tachyarrhythmias were seen in 3 patients, two of them having additional sites of earliest activation.