1Universitätsklinikum Schleswig-Holstein Klinik für Rhythmologie Lübeck, Deutschland
Background: Pulmonary vein isolation (PVI) is an effective treatment strategy for patients with paroxysmal atrial fibrillation (AF). In patients with persistent AF (PersAF) PVI as the sole ablative strategy is associated with limited success rates. In small studies empirical left atrial appendage isolation (LAAI) was associated with a superior outcome compared to PVI alone. Since radiofrequency-based LAAI is often challenging, cryoballoon (CB)-based LAAI might be an option to achieve safe and durable LAAI.
Methods: CB-based PVI and LAAI was performed in 50 patients with PersAF and long-standing PersAF. LAAI was performed using a bonus freeze protocol (freezing time 300 seconds + another 300 seconds after LAAI). Oral anticoagulation with NOAC was continued after ablation. Six weeks after ablation patients were scheduled for 1.) transesophageal echocardiography to rule out LAA thrombi and 2.) for LAA closure to prevent thromboembolism. PVI and LAA reconduction were assessed during LAA closure using a spiral mapping catheter .
Results: LAAI was achieved in 46 (92%) patients with a mean minimal temperature of -54+/- 6°C. One (2%) transient left phrenic nerve palsy and one (2%) retroperitoneal hematoma, managed conservatively, occurred as periprocedural complications. Six weeks after LAAI, a LAA thrombus was detected in 9 (18.4%) patients, however no strokes occurred between LAAI and LAA-closure. Successful LAA-closure was performed in 49 (98%) patients after a median of 52 days (interquartile range 48-95 days). In 7 (14 %) patients a thrombus resolution could be achieved, 2 (4%) patients received LAA-closure despite a thrombus. One (2%) patient refused LAA-closure and stayed on oral anticoagulation. PVI and LAAI were durable in 32 (65%) and 33 (68%) patients. AF reoccurred at the time of LAA-closure in 8 (17.3%) patients .
Conclusions: CB-based PVI and concomitant LAAI is feasible and safe. LAA and PV reconduction occurred in about one in three patients during follow up. Six weeks post ablation a LAA thrombus was detected in approximately one out of five patients despite oral anticoagulation, highlighting the importance of LAA-closure after LAAI .