The importance of extrapulmonary vein triggers and atypical atrial flutter in atrial fibrillation recurrence after cryoablation: Insights from repeat ablation procedures.

INTRODUCTION: It has not been previously investigated whether the recurrence mechanism after cryoballoon ablation (CBA) of paroxysmal atrial fibrillation (AF) is similar to that of radiofrequency catheter ablation (RFCA). We aimed to evaluate the differences of recurrence characteristics between RFCA and CBA after the index procedure. METHODS: A total of 210 patients were enrolled in the study, and 69 patients underwent pulmonary vein (PV) isolation using a 28-mm second-generation CBA. The control group comprising 140 patients underwent PV isolation using an open-irrigated radiofrequency ablation catheter. A total of 69 patients in the CBA group and 69 patients in the RFCA group were investigated after propensity score matching. Recurrence patterns of AF were studied in the repeated procedure. RESULTS: During the index procedure, there was no difference in PV or non-PV triggers between the two groups. Nineteen (27.5%) patients in the CBA group and 19 (27.5%) patients in the RFCA group had recurrence after a follow-up of 11.3 ± 7 months. The Kaplan-Meier curve did not reveal significant difference in recurrence (log-rank, P = 0.364) between the two groups. In the second procedure, the CBA group had more non-PV triggers (63.6%, P = 0.009) and left atrial (LA) flutters (54.5%, P = 0.027) compared with the RFCA group (12.5% and 12.5%, respectively). The PV reconnection rates were similar between both groups. CONCLUSIONS: There was no difference in AF recurrence after catheter ablation between CBA and RFCA, but significant increases of non-PV triggers and LA flutter during the second procedure suggest the importance of the atrial substrate in maintaining AF during the second procedure after previous CBA.

Vasovagal responses during cryoballoon pulmonary vein isolation in paroxysmal atrial fibrillation predict favorable mid-term outcomes.

BACKGROUND: Vasovagal responses (VR) encountered during radiofrequency pulmonary vein isolation (PVI) in paroxysmal atrial fibrillation (PAF) suggest ablation of the atrial tissue subjacent to the ganglionic plexi (GP) and confer durability of PVI. OBJECTIVE: We hypothesized that VR during cryoballoon PVI (CB-PVI) in PAF can predict mid-term AF recurrence. METHODS: We enrolled 39 patients who underwent PVI using 2nd generation cryoballoon for PAF from November 2014 to July 2016. We evaluated the long term outcomes for those who had VR during index procedure. RESULTS: A total of 39 patients (76% male, mean age 57 ±â€¯9 years) underwent CB-PVI for PAF and 66.67% (26/39) had VR. VR was frequently observed in the LSPV (100%), followed by RSPV (64%), LIPV (60%), and less frequently, RIPV (28%). Overall, the mean difference in the HR and SBP, and the relative differences in the HR and SBP were observed during CB-PVI in the LSPV (mean difference in HR, p < 0.001; mean difference in SBP, p < 0.001; relative difference in HR, p < 0.001); relative difference in SBP, p < 0.001). After PVI, 22/26 (84.62%) and 5/13 (38.46%) of patients in the VR and NVR group, respectively, maintained SR at 14 ±â€¯6 months follow-up. The Kaplan-Meier analysis showed statistical difference in favor of patients with VR during CB-PVI (log rank p < 0.01) with a better mid-term outcome. CONCLUSION: In a small cohort of patients, VR during CB-PVI in PAF is a surrogate marker for ablation of atrial tissue subjacent to the GP and predicts a favorable mid-term outcome for AF recurrence.

Occurrence and Dissipation of the Antibiotics Sulfamethoxazole, Sulfadiazine, Trimethoprim, and Enrofloxacin in the Mekong Delta, Vietnam.

The Mekong Delta in Vietnam has seen a rapid development and intensification of aquaculture in the last decades, with a corresponding widespread use of antibiotics. This study provides information on current antibiotic use in freshwater aquaculture, as well as on resulting antibiotic concentrations in the aquatic environment of the Mekong Delta. Two major production steps, fish hatcheries and mature fish cultivation, were surveyed (50 fish farm interviews) for antibiotic use. Different water sources, including surface water, groundwater and piped water (164 water samples) were systematically screened for antibiotic residues. To better understand antibiotic fate under tropical conditions, the dissipation behavior of selected antibiotics in the aquatic environment was investigated for the first time in mesocosm experiments. None of the investigated antibiotics were detected in groundwater and piped water samples. Surface water, which is still often used for drinking and domestic purposes by local populations, contained median concentrations of 21 ng L-1 sulfamethoxazole (SMX), 4 ng L-1 sulfadiazine (SDZ), 17 ng L-1 trimethoprim (TRIM), and 12 ng L-1 enrofloxacin (ENRO). These concentrations were lower than the predicted no effect concentrations (PNECs) and minimum inhibitory concentrations (MICs), suggesting limited antibiotic-related risk to aquatic ecosystems in the monitored systems. The dissipation half-lives of the studied antibiotics ranged from <1 to 44 days, depending on the availability of sunlight and sediment. Among the studied antibiotics TRIM was the most persistent in water systems. TRIM was not susceptible to photodegradation, while the dissipation of ENRO and SDZ was influenced by photolysis. The recorded dissipation models gave good predictions of the occurrence and concentrations of TRIM, ENRO and SDZ in surface water. In summary, the currently measured concentrations of the investigated antibiotics are unlikely to cause immediate risks to the aquatic environment, yet the persistence of these antibiotics is of concern and might lead to chronic exposure of aquatic organisms as well as humans.