RESUMO
BACKGROUND: Local tissue impedance drop (LID) and lesion size index (LSI) technologies are valuable for predicting effective lesion formation. This study compares the acute and long-term efficacy of LID-guided versus LSI-guided pulmonary vein isolation (PVI) for atrial fibrillation treatment. METHODS: We retrospectively analyzed two patient groups undergoing radiofrequency PVI. In the LID-guided group (n = 35), ablation was performed without contact force monitoring, stopping at the LID plateau (target LID 12 Ohm posterior, 16 Ohm anterior). In the LSI-guided group (n = 31), ablation used contact force information with target LSI (5 anterior, 4 posterior). Both groups utilized a power of 40 W anterior and 30 W posterior, with < 6 mm inter-lesion distance. Gap mapping and touch-up ablation were done if necessary. RESULTS: PVI was achieved with a significantly shorter ablation time in the LSI-guided group (25 min [21;31] vs 30 [27;35], p = 0.035). PV gaps were more frequent in the LID-guided group (74% vs 42%, p = 0.016). Over 11.5 ± 2.9 months follow-up, arrhythmia recurrence was higher in the LID-guided group (34.3% vs 16.1%, p = 0.037). A redo procedure performed in 10 (28.6%) patients in the LID-guided group and 3 (9.7%) in the LSI-guided group showed chronic PV reconnections in 7 out of 10 (70%) and 2 out of 3 (67%) patients, respectively. CONCLUSIONS: LSI-guided ablation results in shorter ablation time and fewer PV gaps compared to LID-guided ablation. Despite initial success, LID-guided ablation had higher arrhythmia recurrence and PV reconnections during long-term follow-up compared to LSI-guided ablation.
RESUMO
BACKGROUND: Data about necessity of performing transesophageal echocardiography (TOE) prior to every catheter ablation (CA) of atrial fibrillation (AF) is scarce. We aimed to evaluate the safety of an individualized risk-based approach to TOE with respect to thromboembolic cerebrovascular events (CVE) in patients undergoing CA for AF or left atrial tachycardia (AT). METHODS: We performed a retrospective clinical study based on our institutional registry database. Patients undergoing CA for AF or left-sided AT following initial AF ablation at two participating centers were enrolled. Prior to the procedure, patients were scheduled for TOE only if they had a history of thromboembolic stroke, left atrial appendage (LAA) thrombus, or inappropriate anticoagulation regimen in the previous 3 to 4 weeks. The incidence of periprocedural cerebrovascular thromboembolic events was assessed. RESULTS: We analyzed 1155 patients (median age 70 years, 54.8% male, 48.1% had persistent AF/AT). In 261 patients, a TOE was performed; in 2 patients (0.7%), an LAA thrombus was detected, which led to cancellation of the catheter ablation; in 894 patients, the TOE was omitted. Of the 1153 (0.35%) patients who underwent ablation, 4 (0.35%) experienced a CVE (one TIA and three strokes). The rate of CVE in our study does not exceed that reported in most multicenter trials. The low event rates limited statistical analysis of possible risk factors for CVE. In all 4 patients with CVE, post-CVE imaging showed the absence of LAA thrombus. CONCLUSIONS: An individualized selective approach to TOE before catheter ablation of AF or left AT showed a very low risk of overt intraprocedural thromboembolic events for the population in our study. A further randomized controlled study is needed to determine whether TOE prior to catheter ablation without ICE could be omitted in patients with uninterrupted OAC without previous thromboembolic events or a history of left atrial thrombus.