Abstract 2317: Sinus Node Dysfunction, Tachy-brady Rhythm and Extensive Biatrial Scarring - Recognizing a New Clinical Syndrome of Atriomyopathy in Patients With Atrial Fibrillation
Introduction: Prior studies have shown that patients with sinus node dysfunction (SND) are prone to develop right atrial (RA) scarring and AF. These pts typically need pacemaker (PM) therapy, fail multiple anti arrhythmic drugs (AADs), and are referred for radiofrequency catheter ablation (RFCA). The electrophysiologic properties of these pts and their clinical outcomes have not been well understood.
Methods: Retrospective multicenter study that involves AF pts with SND and PM, referred for RFCA after failing AAD therapy between 2006 and 2007. Pts with known cardiomyopathy, CRT-D therapy, and valvular heart disease were excluded. All patients underwent pulmonary vein antral isolation (PVAI) with or without substrate modification (SM) by complex fractionated electrogram ablation. 3D mapping was used in all cases and left and right atrial voltages were measured and voltages <0.3 mV was defined as scar.
Results: Of 258 patients 30 were included in the study (50% males, 100% Caucasian mean AF duration of 9.2±8 years, BMI of 31.3kg/m2, failed a mean 3±1 AADs, 85% had paroxysmal AF). Sixty percent had prior cavotricuspid isthmus flutter ablation Prevalence of diabetes, HTN, CAD, obstructive sleep apnea and chronic renal insufficiency was 14%, 47%, 28.5%, 0% and 0% respectively. Mean left atrial size was 4.2±0.8 and EF was 56±8. Only 22% percent had arrhythmogenic pulmonary veins with 89% of them showing extensive biatrial scarring (left > right). PVAI with SM was done in all patients. Acute success immediately after ablation was seen in 90% however, 19% remained AF free off AADs and 29% on AADs at 3 months. Redo ablation was offered and performed on 6 more pts. At 1 yr f/u 15% were AF free off AADs and 24% on AADs and the rest continued to have recurrences. Complications included 1 moderate pericardial effusion and a large thigh hematoma needing transfusion.
Conclusion - Patients with SND and tachy-brady syndrome may have extensive atrial scarring suggestive of idiopathic atriomyopathy. RFCA may not be as successful despite PVAI and extensive SM as in other AF subgroups where PV and non PV triggers play a major role.