Atrial fibrillation after typical atrial flutter ablation: a long-term follow-up.

OBJECTIVE: Although catheter ablation is an effective treatment for typical atrial flutter (TFL), atrial fibrillation may occur during follow-up. The aim of this study was to assess the frequency of postablation atrial fibrillation in patients with or without atrial fibrillation before TFL ablation. METHODS: One hundred and ninety-two patients (135 men, age 68 ± 9 years) ablated for TFL were divided into two groups: group 1 (80 patients) with isolated TFL and group 2 (112 patients) with TFL and atrial fibrillation before ablation. The end-point of the study was the occurrence of documented atrial fibrillation after ablation. Several predetermined variables were tested with regard to atrial fibrillation occurrence. The patients' perception of the frequency and severity of arrhythmia-related symptoms was evaluated before and after ablation by means of the Symptom Checklist Frequency and Severity scale (SCFSS). RESULTS: At least one episode of atrial fibrillation was recorded in 18 (22.5%) group 1 and 52 (46%) group 2 patients (P = 0.001), during a follow-up of 1086 ± 825 and 1126 ± 962 days, respectively. On multivariate analysis, independent predictors of atrial fibrillation occurrence in group 1 were the number of preablation episodes of TFL and the younger age of the patients. The 37 group 2 patients who continued to have paroxysmal or persistent atrial fibrillation episodes after ablation showed a significant decrease in atrial fibrillation incidence and hospitalizations. SCFSS significantly improved in the 63 group 2 patients in whom it was evaluated. CONCLUSIONS: On long-term follow-up, after ablation of isolated TFL, more than three-quarters of patients remained free from atrial fibrillation. Conversely, in patients with preablation atrial fibrillation, TFL ablation reduced the number of atrial fibrillation episodes as well as the number of hospitalizations and arrhythmia-related symptoms.

Endoscopic fetal surgery: in vitro thermic effect of electrosurgical units.

OBJECTIVE: The study focused on the safety of electrosurgical devices in endoscopic fetal surgery. The thermic effects of monopolar electric waves were studied in vitro in order to obtain safety indications in terms of mode of intramniotic application of electrical devices (time and number of shots; volts; and distance from tissues to be preserved). STUDY DESIGN: A glass model filled with saline solution, and an electrical device with resistor and voltage supply, were constructed to reproduce the physical effects of thermic conductivity in vitro; a Swan-Ganz thermic sensor was used to measure the temperature inside the beuta. Different series of tests were carried out. RESULTS: The maximal increase (8.60 +/- 0.04 degrees C) takes place at the external surface of the resistor (distance: 0 cm), while at 2 cm, the temperature of the saline solution does not change. CONCLUSIONS: Our tests demonstrate that in order to avoid any kind of risk during electrosurgical procedures on fetuses, the electrode must be placed at least 0.5 cm from delicate tissues.