A Pilot Study on Parameter Setting of VisiTag™ Module during Pulmonary Vein Isolation.

OBJECTIVES: To identify optimal predefined criteria (OPC) for filters of the VisiTag™ module in the CARTO 3 system during pulmonary vein isolation (PVI). METHODS: Thirty patients with atrial fibrillation (AF) who experienced PVI first were enrolled. PVI was accomplished by using a Thermocool SmartTouch catheter. Ablation lesions were tagged automatically as soon as predefined criteria of the VisiTag™ module were met. OPC should be that ablation with the setting resulting in the conduction gap (CG) as few as possible, while contiguous encircling ablation line (CEAL) without the tag gap (TG) on the 3D anatomic model as much as possible. RESULTS: When ablation with parameter setting is being catheter movement with a 3 mm distance limit for at least 20 s and force over time (FOT) being off, there were 60 CEAL without TG on the 3D anatomic model. However, 26 CGs were found. After changing FOT setting to be a minimal force of 5 g with 50% stability time, 22 TGs were displayed. Of them, 20 TGs were accompanied by CGs. On reablation at sites of TG with changed parameter setting, 18 CGs were eliminated when 20 TGs disappeared. When reablation with FOT is being a minimal force of 10 g with 50% stability time, 6 remaining CGs were eliminated. However, there was no CEAL. With a mean of follow-up 10.93 months, 2 patients with persistent AF suffered AF recurrence. CONCLUSION: A 3 mm distance limit for at least 20 s and FOT being a minimal force of 5 g with 50% stability time might be OPC for the VisiTag™ module.

Role of UTS2 gene in the genetic susceptibility to atrial fibrillation in the Chinese population.

OBJECTIVE: Atrial fibrosis plays a key role in the inducibility and persistence of atrial fibrillation. Urotensin II (U-II/UTS2) induces cardiac fibrosis by increasing fibroblast collagen synthesis and increased U-II plasma levels have been reported in patients with atrial fibrosis. Our objective was therefore to evaluate the possible role of the UTS2 gene polymorphisms Thr21Met and Ser89Asn in the genetic susceptibility to atrial fibrillation in a Chinese population. METHODS: A case-control study was designed to compare the distribution of alleles and genotypes between controls (n=197) and patients with AF (n=197). The detection of UTS2 gene polymorphisms was undertaken using the PCR-restriction fragment length polymorphism technique. RESULTS: We identified statistically significant differences between the atrial fibrillation and control groups with regard to the frequency of genotype variant GA at the Ser89Asn locus (OR 1.955, 95% CI 1.071 to 3.566, p=0.029). When stratified by sex, differences in genotype distribution of polymorphism Ser89Asn was only seen in men in the additive tested inheritance model (OR 2.843, 95% CI 1.273 to 6.348, p=0.011). There was a statistical difference in Met21Met, implying a potential beneficial role for atrial fibrillation in the recessive tested inheritance model among men (OR 0.260, 95% CI 0.075 to 0.89, p=0.033; AA vs GA-GG). For subjects with atrial fibrillation, the Met21Met genotype was associated with a larger anteroposterior left atrial diameter (AA vs GG, 4.12±0.62 vs 3.86±0.51, p=0.028) and a smaller left ventricular end-diastolic diameter (AA vs GG, 4.50±0.48 vs 4.78±0.49, p=0.039). CONCLUSIONS: Ser89Asn polymorphisms of the UTS2 gene are significantly associated with atrial fibrillation in the Chinese population. Additionally, we demonstrated that genotype Met21Met may have a potential beneficial role in atrial fibrillation.

Tumor suppressor in lung cancer-1 (TSLC1) mediated by dual-regulated oncolytic adenovirus exerts specific antitumor actions in a mouse model.

AIM: The tumor suppressor in lung cancer-1 (TSLC1) is a candidate tumor suppressor of lung cancer, and frequently inactivated in primary non-small cell lung cancer (NSCLC). In this study, we investigated the effects of TSLC1 mediated by a dual-regulated oncolytic adenovirus on lung cancer, and the mechanisms underlying the antitumor actions. METHODS: The recombinant virus Ad·sp-E1A(Δ24)-TSLC1 was constructed by inserting the TSLC1 gene into the dual-regulated Ad·sp-E1A(Δ24) vector, which contained the survivin promoter and a 24 bp deletion within E1A. The antitumor effects of Ad·sp-E1A(Δ24)-TSLC1 were evaluated in NCI-H460, A549, and H1299 lung cancer cell lines and the normal fibroblast cell line MRC-5, as well as in A549 xenograft model in nude mice. Cell viability was assessed using MTT assay. The expression of TSLC1 and activation of the caspase signaling pathway were detected by Western blot analyses. The tumor tissues from the xenograft models were examined using H&E staining, IHC, TUNEL, and TEM analyses. RESULTS: Infection of A549 lung cancer cells with Ad·sp-E1A(Δ24)-TSLC1 induced high level expression of TSLC1. Furthermore, the Ad·sp-E1A(Δ24)-TSLC1 virus dose-dependently suppressed the viability of NCI-H460, A549, and H1299 lung cancer cells, and did not affect MRC-5 normal fibroblast cells. Infection of NCI-H460, A549, and H1299 lung cancer cells with Ad·sp-E1A(Δ24)-TSLC1 induced apoptosis, and increased activation of caspase-8, caspase-3 and PARP. In A549 xenograft model in nude mice, intratumoral injection of Ad·sp-E1A(Δ24)-TSLC1 significantly suppressed the tumor volume, and increased the survival rate (from less than 15% to 87.5% at d 60). Histological studies showed that injection of Ad·sp-E1A(Δ24)-TSLC1 caused tumor cell apoptosis and virus particle propagation in tumor tissues. CONCLUSION: The oncolytic adenovirus Ad·sp-E1A(Δ24)-TSLC1 exhibits specific antitumor effects, and is a promising agent for the treatment of lung cancer.