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The tracheal Y-shaped stent is mainly used for the treatment of critical patients with airway stenosis or esophagotracheal fistula near carina. A novel method for precise implantation of Y-shaped tracheal stents was developed using double-lumen endotracheal intubation and flexible bronchoscopy. This approach aims to address the limitations associated with X-ray or rigid bronchoscopy guidance, such as operational difficulties and the risk of inaccurate stent placement leading to implantation failure or suffocation. With this new technique, 13 tracheal Y-shaped stents were successfully implanted. This method shows promise in reducing the complexity of stent implantation and facilitating timely treatment for patients in need. Additionally, it has the potential to update current operating standards and guidelines for this procedure., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ding, Ding, Duan, Chen, Li, Ren and Sun.)

Background and Objective: Current methods for imaging reconstruction from high-ratio expansion microscopy (ExM) data are limited by anisotropic optical resolution and the requirement for extensive manual annotation, creating a significant bottleneck in the analysis of complex neuronal structures., Methods: We devised an innovative approach called the IsoGAN model, which utilizes a contrastive unsupervised generative adversarial network to sidestep these constraints. This model leverages multi-scale and isotropic neuron/protein/blood vessel morphology data to generate high-fidelity 3D representations of these structures, eliminating the need for rigorous manual annotation and supervision. The IsoGAN model introduces simplified structures with idealized morphologies as shape priors to ensure high consistency in the generated neuronal profiles across all points in space and scalability for arbitrarily large volumes., Results: The efficacy of the IsoGAN model in accurately reconstructing complex neuronal structures was quantitatively assessed by examining the consistency between the axial and lateral views and identifying a reduction in erroneous imaging artifacts. The IsoGAN model accurately reconstructed complex neuronal structures, as evidenced by the consistency between the axial and lateral views and a reduction in erroneous imaging artifacts, and can be further applied to various biological samples., Conclusion: With its ability to generate detailed 3D neurons/proteins/blood vessel structures using significantly fewer axial view images, IsoGAN can streamline the process of imaging reconstruction while maintaining the necessary detail, offering a transformative solution to the existing limitations in high-throughput morphology analysis across different structures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

An integrated aberration-compensating module (IACM), consisting mainly of an adjustable slab-aberration compensator, a one-dimensional Shack-Hartmann wavefront sensor, and a data processor, which meet the urgent requirements of correcting the specific wavefront aberrations of a slab laser based on an off-axis stable-unstable resonator, is designed and experimentally demonstrated. Benefits include compactness, robustness, simplicity, automation, and cost-effectiveness. The particular wavefront aberrations of the 9 kW level quasi-continuous-wave Nd:YAG slab laser, which have characteristics of asymmetry, large amplitude and gradient, high spatial frequency, and low temporal frequency, were measured and theoretically analyzed. In the experiment, the wavefront aberrations of the slab laser were corrected by the IACM. At the average output power of 9 kW, the diffraction-limited factor β was improved from 20.3 times diffraction limit (DL) to 3.6 times DL. The peak-to-valley and root-mean-square values of aberrations were reduced from 9.6 to 0.85 µm and from 2.86 to 0.18 µm within five iterations of the IACM, respectively. Moreover, The IACM is capable of maintaining the compensating surface figure after power-off.

Phytochemical investigation on the 95% alcohol extract of the aerial part of Inula japonica led to the isolation of three new compounds, inulanolides F-G ( 1-2 ) and 17 α -carboxaldehyde-ent-kaur-18-oic acid ( 3 ), together with four known compounds ( 4-7 ). The structures of new compounds were elucidated by using spectroscopic data. Most of the isolated compounds showed significant anti-inflammatory activities.

Background: Leucine-rich repeat kinase 2 (LRRK2) is a common risk gene for Parkinson's disease (PD) and inflammatory bowel disorders. However, the penetrance of the most prevalent LRRK2 mutation, G2019S, is <50%. Factors other than genetic mutations are needed in PD process., Objectives: To examine whether and how gut inflammation may act as an environmental trigger to neurodegeneration in PD., Methods: A mild and chronic dextran sodium sulfate (DSS)-induced colitis mice model harboring LRRK2 G2019S mutation was established. The colitis severity, immune responses, locomotor function, dopaminergic neuron, and microglia integrity were compared between littermate controls, transgenic LRRK2 wild type (WT), and LRRK2 G2019S mice., Results: The LRRK2 G2019S mice are more vulnerable to DSS-induced colitis than littermate controls or LRRK2 WT animals with increased intestinal expressions of pattern-recognition receptors, including toll-like receptors (TLRs), nuclear factor (NF)-κB activation, and pro-inflammatory cytokines secretion, especially tumor necrosis factor (TNF)-α. Notably, the colonic expression of α-synuclein was significantly increased in LRRK2 G2019S colitis mice. We subsequently observed more aggravated locomotor defect, microglia activation, and dopaminergic neuron loss in LRRK2 G2019S colitis mice than control animals. Treatment with anti-TNF-α monoclonal antibody, adalimumab, abrogated both gut and neuroinflammation, mitigated neurodegeneration, and improved locomotor function in LRRK2 G2019S colitis mice. Finally, we validated increased colonic expressions of LRRK2, TLRs, and NF-κB pathway proteins and elevated plasma TNF-α level in PD patients compared to controls, especially in those with LRRK2 risk variants., Conclusions: Our findings demonstrate that chronic colitis promotes parkinsonism in genetically susceptible mice and TNF-α plays a detrimental role in the gut-brain axis of PD. © 2021 International Parkinson and Movement Disorder Society., (© 2021 International Parkinson and Movement Disorder Society.)

We present a kilowatt-level quasi-continuous-wave (QCW) cryogenically cooled 946-nm slab laser oscillator for the first time, to the best of our knowledge. The laser system is based on a double-face-pumped large-size single-slab Nd:YAG design, delivering a record-high average power of 1.06 kW without additional amplification. This laser oscillator operates at repetition rate of 400 Hz with a pulse duration of 175 µs, resulting in a single pulse energy of 2.65 J. To the best of our knowledge, these results represent the highest output power and pulse energy for any all-solid-state 946-nm laser ever reported to date. Our scheme paves a new path for the development of the compact high-power solid-state 946-nm laser.

The geometric aberration of centered refracting double-plane symmetric optical systems (DPSOS) is investigated. For DPSOS with different defocus values in the tangential plane and the sagittal plane (astigmatic wavefront), a pair of curved reference surfaces which vanishes the quadratic terms of the optical path difference (OPD) between a general ray and a reference ray are deduced. With the curved reference surfaces, the primary (fourth-order) wave aberration function for DPSOS is calculated and analyzed, which can be used for beam shaping designs with astigmatic input wavefront, such as slab lasers and semiconductor lasers. Further, the proposed curved reference surfaces can be applied to analyze the aberrations of general DPSOS.

Purpose: To evaluate the peripapillary changes after vitrectomy and silicone oil (SO) tamponade in eyes with rhegmatogenous retinal detachment (RRD)., Methods: In this study, 25-gauge vitrectomy with SO tamponade was performed in 22 eyes with RRD. The radial peripapillary capillary (RPC) vessel density (VD) and retinal nerve fiber layer thickness (RNFLT) were assessed by optical coherence tomography angiography at 2, 4, 8, and 12 weeks postoperatively. The values of healthy fellow eyes were used as controls., Results: The global RPC VDs were significantly lower in the eyes with RRD than in fellow healthy eyes at 2 weeks (P < 0.001), and increased at 4 weeks, then decreased over time after surgery (F = 1.046, P = 0.377). The RPC VDs in the superior-hemifield were lower than those in the inferior-hemifield at 12 weeks postoperatively (t = -2.844, P = 0.010). The global RNFLTs decreased gradually after vitrectomy in the eyes with RRD (F = 1.312, P = 0.276). The RNFLTs in the superior-hemifield were thinner than those in the inferior-hemifield at 12 weeks postoperatively (t = -2.222, P = 0.037). The global, superior, and inferior RNFLTs were correlated with corresponding RPC VDs in the eyes with RRD at all time-points postoperatively (P < 0.05)., Conclusion: RRD resulted in the decrease of RPC VDs. The RPC VDs recovered in the early postoperative period but were still lower than the normal level. Long-term application of SO tamponade resulted in the reduction of peripapillary VDs secondary to loss of RNFLTs., Competing Interests: None

For reshaping aperture size and correcting low-order aberration of laser beams with large aspect ratios, a simplified analytical method is proposed to design an anamorphic refractive shaping system, which is composed of double-plane symmetric lenses. The simplified method enables performing a global study of aberrations via calculating the analytical primary wave aberration function under paraxial approximation. The aberration balance is analyzed with a three-lens laser collimating system and a compact four-lens laser expanding system. Lens bending and conic surfaces are introduced to decrease ray errors. Through the simplified analytical method, anamorphic refractive shaping systems for laser beams with large aspect ratios can be adequately analyzed and conveniently designed.

Aim: To evaluate macular microvasculature changes in eyes after pars plana vitrectomy (PPV) and intraocular silicone oil (SO) tamponade for macula-off rhegmatogenous retinal detachment (RRD) using optical coherence tomography angiography (OCTA)., Methods: Totally 19 eyes (19 patients) with macula-off RRD who underwent PPV and intraocular SO tamponade were retrospectively reviewed. The parafoveal superficial capillary plexus (SCP) vessel density (VD), deep capillary plexus (DCP) VD, choriocapillaris plexus (CCP) VD, and foveal macular thickness were evaluated using OCTA throughout 16wk postoperatively. The values of healthy fellow eyes were used as control., Results: The parafoveal SCP, DCP, and CCP VDs were significant increased over time in RRD eyes during the 12wk postoperatively, then decreased at 16wk postoperatively (all P <0.01). The ratios of RRD eyes and fellow healthy eyes (r/f ratios) of the SCP and DCP VDs were lower than those of the CCP VD postoperatively (all P <0.05). There were not significant differences in the r/f ratios between SCP and DCP VDs postoperatively (all P >0.05)., Conclusion: The parafoveal SCP, DCP, and CCP VDs gradually recover over time after PPV surgery with SO tamponade. Long-time SO tamponade might decrease postoperative macular VDs. Compared to parafoveal CCP VD, the parafoveal SCP and DCP VDs were more vulnerable in RRD eyes postoperatively., (International Journal of Ophthalmology Press.)

A void-free bonding technique was demonstrated for a large slab Nd: YAG crystal with a bonding surface dimension of ∼160 m m ×70 m m . By using the novel fluxless oxide layer removal technology, the indium-oxide barrier problem was resolved. With the help of electrochemical-polished indium solder and a plasma-cleaned heat sink, the solderability of the indium was enhanced; in particular, the contact angle of the solder was improved from 51° to 31°. With the largest-bonding-size slab, a single-slab laser created a maximum output power of 7.3 kW under an absorbed pump power of 12.8 kW, corresponding to an optical to optical efficiency of 57% and a slope conversion of 67.8%. By detecting the wavefront of the interferometer before and after bonding, the RMS of wavefront was 0.192 λ and 0.434 λ ( λ =633 n m ), respectively. To the best of our knowledge, this is the largest void-free bonding size for a laser slab and the highest output power achieved from a single-slab crystal laser oscillator.

Aim: The aim of the study was to investigate the interchangeability and reliability of macular perfusion measurements using optical coherence tomography angiography., Methods: A prospective cross-sectional observational study. Healthy adult Chinese subjects were recruited. Macular perfusion parameters were automatically analysed by software included in a spectral-domain optical coherence tomography system. The vessel density (VD) of the whole, parafovea, superior-hemi, inferior-hemi, fovea, temporal, superior, nasal and inferior quadrants as well as the foveal avascular zone (FAZ) and choroidal capillary VD (CCVD) were quantified., Results: A total of 51 eyes in 27 subjects were included (8 men and 19 women, mean age 24±4 years ). Significant differences in VD of all quadrants (all p<0.001) was detected between the 3×3 mm and 6×6 mm macular scan size. The biggest difference of VD between the two scan size was 5.14±4.03, which was not clinically meaningful. No statistically significant differences were found in FAZ or CCVD between the two different scan sizes. The mean intraclass correlation coefficient (ICC) between two measurements from the inter-rater of 20 eyes was from 0.560 to 0.893 for VD and 0.845 for FAZ. The mean ICC between two measurements from the intrarater of 20 eyes was from 0.497 to 0.870 for VD and 0.780 for FAZ., Conclusions: FAZ and CCVD are interchangeable between the 3×3 mm and 6×6 mm macular scan sizes. The VD differences between the two different scan sizes are not clinically meaningful. The macular perfusion parameters presented good but not perfect reliability, which should be acknowledged in clinical practice., Competing Interests: Competing interests: OHSU, YJ and DH have a significant financial interest in Optovue. DH also has a financial interest in Carl Zeiss Meditec. These potential conflicts of interest have been reviewed and managed by OHSU., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Aim: To compare the changes in corneal biomechanics measured by ocular response analyzer (ORA) after 2.2-mm microincision cataract surgery and 3.0-mm standard coaxial phacoemulsification., Methods: The prospective nonrandomized study comprised eyes with cataract that had 2.2-mm coaxial microincision or 3.0-mm standard incision phacoemulsification. The corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc) and Goldmann-correlated intraocular pressure (IOPg) were measured by ORA preoperatively and at 1d, 1-, 2-, 3- and 4-week postoperatively. Results were analyzed and compared between groups., Results: In both groups, CH decreased in the immediate postoperative period (P<0.05), returned to the preoperative level at one week (P=0.249) in the 2.2-mm group, and at two weeks in the 3.0-mm group (P=0.264); there was no significant change in CRF values. In 2.2-mm group, mean IOPcc and IOPg increased at 1d postoperatively (both P<0.05), and returned to preoperative level at one week (P=0.491 and P=0.923, respectively). In 3.0-mm group, mean IOPcc and IOPg increased at 1d and 1wk postoperatively (P=0.005 and P=0.029, respectively), and returned to preoperative level at 2wk (P=0.347 and P=0.887, respectively)., Conclusion: Significant differences between preoperative and postoperative corneal biomechanical values were found for CH, IOPcc and IOPg. But the recovery time courses were different between the two groups. The 2.2-mm coaxial microincision cataract surgery group seemed recovery faster compared to the 3.0-mm standard coaxial phacoemulsification group.

An 8 kW level quasi-continuous-wave (QCW) face-pumped 1064 nm slab laser with high beam quality was developed by a master oscillator power amplifier (MOPA) system. A single-mode fiber seed laser was amplified by two-stage single-pass Nd:YAG rod preamplifiers and four face-pumped Nd:YAG slab amplifiers. The slab amplifiers were well designed with uniform pumping and uniform cooling for well-distributed thermal and stress. A dynamically feedbacked optical aberration compensation device was employed to correct low-order optical aberration, and the residue high-order optical aberration was corrected by an adaptive optics system. The QCW MOPA delivered up to an average power of 8.2 kW with a pulse duration of 200 μs at a repetition rate of 400 Hz. The beam quality factor was measured to be β=3.5.

Overexpression of P-glycoprotein leads to tumor multidrug resistance (MDR). HZ08, a novel tetrahydro-isoquinoline derivate, was discovered to inhibit the MDR in the cancer cell lines of MCF-7/ADM, K562/ADM and KBV in our previous studies. A rapid and sensitive ultra-performance liquid chromatography-tandem mass spectrometric method (UPLC-MS/MS) was developed and validated for determination of HZ08 in rat plasma and tissues after intravenous administration of HZ08 liposome injection at different doses. The analytes were extracted from plasma and tissues using protein precipitation by acetonitrile with clotrimazole as internal standard. The chromatographic separation was performed on a Thermo BDS HYPERSIL C18 column (100 mm × 4.6mm, 2.4 μm) at a flow rate of 0.7 ml/min using 0.2% ammonium acetate solution (containing 0.1% formic acid) and methanol as mobile phase. The total run time was 4 min. The tandem mass detection was applied with electrospray ionization in positive ion selected reaction monitoring mode. The ion transitions monitored were m/z 523.5 to 342.3 for HZ08 and 277.1 to 165.1 for the internal standard, respectively. The calibration curves obtained were linear in different matrices, and the lower limit of quantification (LLOQ) achieved was 1 ng/ml for rat plasma and 0.25 ng/ml for rat tissues, respectively. The RSDs for intra- and inter-day precision were less than 15%. Extraction recovery, matrix effect and stability were satisfactory in rat plasma and tissues. The developed method was successfully applied to a pharmacokinetic study of HZ08 liposome injection following intravenous administration of 1, 3, 10mg/kg to Sprague-Dawley rats. The data profiles revealed that HZ08 had linear pharmacokinetic properties at the tested doses, and was rapidly distributed into the systemic circulation with wide distribution throughout the body followed by a rapid elimination phase. The major distribution tissues of HZ08 in rats were lung, spleen and liver. These results provided constructive contribution to support the clinical evaluation., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Continuous wave 808 nm pump laser-induced thermal damage of polycrystalline transparent ceramic and crystalline Nd:YAG materials was investigated both experimentally and theoretically. The measured temperature agrees well with the theoretical simulation, and the maximum hoop stresses occur on the incident facet of the end-pumped rod at about √2 times of the pump beam radius w0, where the temperature gradient is the highest and the damage occurs first at this location. The fracture-limited laser intensity of ceramics was experimentally measured to be 6.4±0.6  kW/cm2, nearly 64% higher than that of the crystals (3.9±0.3  kW/cm2). The deduced thermal fracture stress for ceramic was 386±50  MPa, which is 64% higher than that of the crystals (235±16  MPa).

We present a compact high-efficiency and high-average-power diode-side-pumped Nd:YAG rod laser oscillator operated with a linearly polarized fundamental mode. The oscillator resonator is based on an L-shaped convex-convex cavity with an improved module and a dual-rod configuration for birefringence compensation. Under a pump power of 344 W, a linearly polarized average output power of 101.4 W at 1064 nm is obtained, which corresponds to an optical-to-optical conversion efficiency of 29.4%. The laser is operated at a repetition rate of 400 Hz with a beam quality factor of M(2)=1.14. To the best of our knowledge, this is the highest optical-to-optical efficiency for a side-pumped TEM(00) Nd:YAG rod laser oscillator with a 100-W-level output ever reported.

Background: Studies have demonstrated that improvement in cardiovascular risk factors may contribute to reduced coronary artery disease (CAD) morbidity and mortality, improved patient outcomes, and lower medical costs associated with treating heart disease., Purpose: The purpose of this study was to understand the coronary risk factor profile, to have the knowledge of risk factors, to understand the modifying behaviors, and to understand the factors associated with modifying behaviors of cardiovascular risk factors among patients with CAD in northern Taiwan., Methods: A cross-sectional design was used in this study. Using nonprobability sampling, 156 patients diagnosed with CAD were interviewed and asked to complete a structural questionnaire in cardiovascular clinics at three medical centers in northern Taiwan. Data were analyzed by descriptive analysis, Pearson's correlation, chi-square tests, and stepwise multiple regression., Results: A total of 38% of variance of modifying behaviors was explained by self-efficacy, actual risk factors, work status, and health beliefs. Self-efficacy was the strongest predictor of behavior to modify cardiovascular risk factors. Age and type "A" personality were the two leading cardiovascular risk factors for the participants. Most participants could perform modifying behaviors such as taking medications, eating an appropriate diet, and following specific lifestyle recommendations. However, participants had relatively lower adherence to monitoring blood pressure, exercising regularly, and controlling weight., Conclusions/implications for Practice: Nurses should assess patient cardiovascular risk factors, health beliefs, and self-efficacy and then provide comprehensive and adequate instruction to each based on his or her specific risk factors.

Objective: To investigate the role of endothelial function, inflammatory markers, and N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with impaired chronotropic response during exercise test., Methods: 86 subjects were enrolled. Treadmill exercise test was conducted according to the modified Bruce protocols. Brachial ultrasound was used to measure endothelium dependent flow mediated vasodilatation (FMD). Chronotropic incompetence was defined as either failure to achieve 85% of the age predicted maximum heart rate or a low chronotropic index (< 0.8)., Results: Of the 86 patients, 20 (23%) exhibited chronotropic incompetence. The patients were divided into three groups according to chronotropic index: group 1, < 0.8 (n = 20); group 2, 0.8-1.0 (n = 26); and group 3, > 1.0 (n = 40). Patients with impaired chronotropic response had significantly lower FMD than those with higher chronotropic response (mean (SD) 2.8 (1.9)% v 5.0 (2.8)% v 5.3 (2.5)%, p = 0.002, for groups 1, 2, and 3, respectively). Serum concentrations of high-sensitivity C reactive protein (hsCRP), monocyte chemoattractant protein-1 (MCP-1), and NT-proBNP were significantly higher in group 1 than in groups 2 and 3 (hsCRP: 19 (12) v 9 (6) v 9 (6) mg/l, p < 0.05; MCP-1: 140 (51) v 133 (60) v 108 (46) pg/ml, p = 0.046; NT-proBNP: 4760 (1980) v 3710 (850) v 3910 (1060) mg/l, p = 0.019, respectively). In addition, chronotropic index was significantly related to FMD (r = 0.380, p = 0.001) and inversely related to hsCRP (r = -0.267, p = 0.013). By multivariate analysis, impaired chronotropic response was significantly related to endothelial dysfunction (p = 0.012)., Conclusion: Patients with impaired chronotropic response to graded exercise had endothelial dysfunction, enhanced systemic inflammation, and higher NT-proBNP concentrations. These findings may partly explain the mechanism of chronotropic incompetence as a predictor of cardiovascular risk and increased mortality.

Background: Interleukin-18 (IL-18), a novel proinflammatory marker, and matrix metalloproteinase-9 (MMP-9) represent the indices of plaque stability. It is unknown whether hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins), which provide anti-inflammatory and endothelium protection effects, have the property of stabilizing plaque in patients with hypercholesterolemia., Hypothesis: The study was designed to investigate the influence of statin therapy in circulating IL-18, MMP-9, and endothelial function., Methods: We investigated the effects of a 12-week therapy with fluvastatin on IL-18, MMP-9, and endothelial function in patients with hypercholesterolemia., Results: Compared with placebo, fluvastatin significantly improved flow-mediated vasodilatation to hyperemia, a hallmark of endothelial function [from 3.8% (-3.9 approximately 15.2) to 5.9% (-0.3 approximately 13.2), p = 0.001], and attenuated plasma levels of high sensitivity C-reactive protein (hsCRP) [from 1.3 (0.3 approximately 7.7) to 1.1 mg/l (0.2 approximately 3.5), p = 0.018], IL-18 [from 247.6 (145.4 approximately 378.4) to 196.4 pg/dl (90.7 approximately 380.2), p <0.001], total MMP-9 (from 58 +/- 46.3 to 39.4 +/- 22.4 ng/dl, p = 0.023), and MMP-9 activity [from 6.4 (3.6 approximately 27) to 5.6 ng/dl (3.1 approximately 13.7)]. However, no significant correlation was found between the degree of changes in lipid profile and flow-mediated dilatation (FMD) and plasma concentration of IL-18 and MMP-9., Conclusions: Fluvastatin reduced plasma concentrations of IL-18 and MMP-9, and improved endothelial function in patients with hypercholesterolemia independent of its lipid-lowering effect.

Paroxysmal atrial fibrillation (PAF) can be initiated by ectopic activation from the crista terminalis. The crista terminalis conduction gap is also a critical isthmus in atrial reentrant arrhythmias like upper and lower loop reentry. The aim of this study was to investigate the mechanism and results of catheter ablation for complex atrial arrhythmias originating from the crista terminalis using the noncontact mapping system (NCM). The study population consisted of six patients (5 men, 1 woman; 70 +/- 9 years) with drug refractory PAF and typical/atypical atrial flutter. NCM identified the earliest ectopic activation originating from the crista terminalis in these six patients. The reentry circuit of atypical atrial flutter propagated around the upper crista terminalis in five patients, and lower crista terminalis in one patient. The reentry circuit of atypical atrial flutter and the initial reentry circuit of AF conducted through the crista terminalis gap in all patients. Radiofrequency applications were delivered on the sites of ectopy, which initiated AF. Substrate modification was also performed over the crista terminalis gap (six patients) and cavotricuspid isthmus (three patients) responsible for the reentry. During a mean follow-up of 9 +/- 5 months (range 5-18 months), five patients were free of AF without antiarrhythmic drugs, and one patient did not have AF or atrial flutter using propafenone. NCM demonstrated the mechanism of crista terminalis ectopy-initiating AF and associated typical/atypical atrial flutter. Catheter ablation of crista terminalis ectopy and substrate for the reentry guided by NCM successfully eliminated these atrial arrhythmias.

Elevated plasma levels of asymmetric dimethylarginine (ADMA) have been associated with attenuated endothelium-dependent vasodilation in hypercholesterolemic patients. However, whether lowering of plasma cholesterol concentration by hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) can reduce plasma ADMA levels is still not clear. This study was a multicenter, randomized, double-blind, placebo-controlled design including 46 patients with elevated low-density lipoprotein cholesterol levels. Patients were randomized into 2 groups: rosuvastatin 10 mg/day and placebo for 6 weeks. Plasma levels of ADMA, 8-isoprostane (as a marker of oxidative stress), homocysteine, and high-sensitivity C-reactive protein were measured at baseline and 6 weeks later. Endothelial function assessed by flow-mediated vasodilation of the brachial artery was performed in 11 patients in the rosuvastatin group and in 12 in the placebo group. Baseline characteristics of both groups were similar, and the plasma ADMA levels were significantly correlated with 8-isoprostane (r = 0.388, p = 0.008). After 6 weeks of treatment, plasma ADMA levels were significantly reduced in the rosuvastatin group (from 0.60 +/- 0.19 to 0.49 +/- 0.10 micromol/L, p <0.001). Increases in flow-mediated vasodilation were positively correlated with reductions in plasma levels of ADMA (p = 0.017) and low-density lipoprotein cholesterol (p <0.001). Thus, our findings suggest that treatment with rosuvastatin in patients with hypercholesterolemia may lead to a significant reduction in plasma ADMA levels, which appear to be related to the improvement in endothelial function by rosuvastatin.

Introduction: The outcome of patients with early recurrence of atrial fibrillation (AF) (within one month) after ablation procedure is controversial. Furthermore, the predictors of early and late (up to mean follow-up 30 months) recurrence of AF are not investigated in depth., Aims of the Study: The aim of the present study was to investigate the predictors of early and late recurrence of AF after catheter ablation of arrhythmogenic foci initiating AF in patients with paroxysmal AF., Methods and Results: The study included 207 patients (155 men; mean age 62 +/- 13 years) who received catheter ablation of paroxysmal AF. Eighty-one (39%) patients had early recurrence of AF. Five clinical variables were related to the early recurrence of AF: (1) old age (>/=65 years) ( P = 0.004); (2) presence of associated cardiovascular disease ( P = 0.01); (3) presence of multiple AF foci ( P = 0.004); (4) presence of AF foci from left atrial free wall ( P = 0.039); (5) left atrial enlargement ( P = 0.038). Multivariate analysis demonstrated that presence of multiple AF foci could predict early recurrence of AF ( P = 0.013; ratio = 2.24; 95% CI 1.18 to 4.25). During the follow-up period (30 +/- 11 months), 70 (34%) patients had late recurrence of AF, and two clinical variables were related to the late recurrence of AF: (1) presence of early recurrence of AF ( P = 0.025); (2) presence of multiple AF foci ( P = 0.034). Multivariate analysis found that presence of early recurrence of AF could predict late recurrence of AF ( P = 0.046; hazard ratio = 1.62; 95% CI 1.01 to 2.59). Late recurrence of AF happened in 35 (43%) of the 81 patients with early recurrence of AF, and in 35 (28%) of the 126 patients without early recurrence of AF., Conclusions: Early AF recurrence could predict late AF recurrence.

Objectives: The aim of the study was to investigate the conduction properties and anisotropy of the crista terminalis (CT) in patients with atrial flutter (AFL) using non-contact mapping., Background: The CT is a posterior barrier during typical AFL. However, the CT has transverse conduction capabilities in patients with upper loop re-entry (ULR)., Methods: Twenty-two patients (16 males, 63 +/- 15 years) with typical AFL and ULR were included. Non-contact mapping of the right atrium during AFL and pacing from coronary sinus (CS) and low anterolateral right atrium (LARA) was performed to evaluate transverse conduction across the CT. During ULR, the longitudinal (CV(L)) and transverse (CV(T)) conduction velocity along and across the CT were measured. The width of the CT conduction gap was evaluated to guide radiofrequency ablation (RFA)., Results: No transverse CT gap conduction was found during typical AFL. Transverse CT gap conduction was found in three patients during CS pacing and in three patients during LARA pacing. During ULR, CV(L) was greater than CV(T) (1.28 +/- 0.43 vs. 0.73 +/- 0.30 m/s, p < 0.001). The CV(L)/CV(T) ratio was 1.95 +/- 0.77, which was inversely related to the CT gap width (15.7 +/- 6.8 mm) (p < 0.001). The RFA of the CT gap was successful in 18 patients. Four patients had recurrence of arrhythmias during the follow-up of 11 +/- 3 months., Conclusions: Most of the CT conduction gaps were functional and only appeared during ULR. The width of the CT gap was inversely related to the anisotropic ratio of the CT. The RFA of the CT gap was effective in eliminating ULR.

Introduction: The aim of this study was to delineate activation patterns around the crista terminalis (CT) using high-resolution noncontact mapping., Methods and Results: Twenty-six patients with typical atrial flutter (20 counterclockwise and 6 clockwise) were enrolled in the study. A noncontact mapping system was used to map atrial flutter. There were three activation patterns around the line(s) of block. Type I (n = 6) showed activation around a single complete line of block located in the CT. Type II (n = 17) showed activation around a single incomplete line of block with a conduction gap in the CT. Type III (n = 3) showed activation around double lines of block, one located in the CT and the other located in the sinus venosa region. Simultaneous activation around the tricuspid annulus and through the CT gap could result in double loop reentry (n = 12). After successful ablation of the cavotricuspid isthmus (CTI) in 24 patients, upper loop reentry was still induced in 12 patients with double loop reentry. Subsequent ablation of the CT gap was performed successfully in these 12 patients, and no arrhythmia was inducible thereafter. During the follow-up period of 8.4 +/- 4.1 months, there was no recurrence of atrial flutter in any patient., Conclusion: During typical atrial flutter, the CT might be an incomplete barrier. Simultaneous conduction through the CTI and CT gap could result in double loop reentry. Radiofrequency ablation of the CTI and CT gap was effective in eliminating this arrhythmia.

Background: This study investigated the electrophysiologic characteristics, atrial activation pattern, and effects of radiofrequency (RF) catheter ablation guided by noncontact mapping system in patients with focal atrial tachycardia (AT)., Methods and Results: In 13 patients with 14 focal ATs, noncontact mapping system was used to map and guide ablation of AT. AT origins were in the crista terminalis (n=8), right atrial (RA) free wall (n=3), Koch triangle (n=1), anterior portion of RA-inferior vena cava junction (n=1), and superior portion of tricuspid annulus (n=1); breakout sites were in the crista terminalis (n=5), RA free wall (n=5), middle cavotricuspid isthmus (n=2), and RA-superior vena cava junction (n=2). ATs arose from the focal origins (11 ATs inside or at the border of low-voltage zone), with preferential conduction, breakout, and spread to the whole atrium. After applications of RF energy on the earliest activation site or the proximal portion of preferential conduction from AT origin, 13 ATs were eliminated without complication. During the follow-up period (8+/-5 months), 11 (91.7%) of the 12 patients with successful ablation were free of focal ATs., Conclusions: Focal AT originates from a small area and spreads out to the whole atrium through a preferential conduction. Application of RF energy guided by noncontact mapping system was effective and safe in eliminating focal AT.

Introduction: Recently, several studies showed that focal atrial fibrillation (AF) can be initiated by ectopic beats from the vein of Marshall (VOM). However, the incidence and best fluoroscopic views of VOM have never been reported., Methods and Results: 106 patients (Non-AF = 52, AF = 54) underwent balloon-occluded coronary sinus angiography using seven fluoroscopic views (PA, Lateral, RAO 30 degrees, RA 30 degrees + Caudal 20 degrees, LAO 30 degrees, LAO 60 degrees, LAO 60 degrees + Cranial 20 degrees ). The total incidence of VOM was 74.5% (79/106), without significant difference in age (81.1 vs. 71.0%, >65 vs.

Some patients with atrial fibrillation (AF) treated by antiarrhythmic drugs (AAD) can develop typical atrial flutter, but the mechanism is not clear. This study included 21 patients with AF. Group I (n = 7) had typical atrial flutter due to amiodarone therapy. Group II (n = 7) did not develop atrial flutter after amiodarone treatment. Group III (n = 7) did not receive AAD treatment. A 7 Fr, 20-pole electrode catheter was placed along the CT identified by fluoroscopy and intracardiac echocardiography. After restoration of the sinus rhythm, decremental pacing near the CT was performed until 2 to 1 atrial capture. Complete transverse conduction block was defined as the appearance of double potentials with opposite activation sequence along the CT. Focal transverse conduction delay was defined as the appearance of double potentials at > or = 2 recording sites. Focal transverse conduction delay was observed during pacing at the cycle length of 693 +/- 110 ms in group I, 360 +/- 97 ms in group II and 343 +/- 109 ms in group III (P = 0.001). Complete transverse conduction block was observed during pacing at the cycle length of 391 +/- 118 ms in group I and 231 +/- 23 ms in group II (P = 0.001), but not in group III. In conclusion, focal transverse conduction delay in the CT was common in patients with AF. A predisposition to the line of the conduction block in the CT might contribute to the conversion of AF to typical atrial flutter due to amiodarone therapy.

Introduction: The incidence of spontaneous transition of 2:1 AV block to 1:1 AV conduction during AV nodal reentrant tachycardia has not been well reported. Among previous studies, controversy also existed about the site of the 2:1 AV block during AV nodal reentrant tachycardia., Methods and Results: In patients with 2:1 AV block during AV nodal reentrant tachycardia, the incidence of spontaneous transition of 2:1 AV block to 1:1 AV conduction and change of electrophysiologic properties during spontaneous transition were analyzed. Among the 20 patients with 2:1 AV block during AV nodal reentrant tachycardia, a His-bundle potential was absent in blocked beats during 2:1 AV block in 8 patients, and the maximal amplitude of the His-bundle potential in the blocked beats was the same as that in the conducted beats in 4 patients and was significantly smaller than that in the conducted beats in 8 patients (0.49 +/- 0.25 mV vs 0.16 +/- 0.07 mV, P = 0.007). Spontaneous transition of 2:1 AV block to 1:1 AV conduction occurred in 15 (75%) of 20 patients with 2:1 AV block during AV nodal reentrant tachycardia. Spontaneous transition of 2:1 AV block to 1:1 AV conduction was associated with transient right and/or left bundle branch block. The 1:1 AV conduction with transient bundle branch block was associated with significant His-ventricular (HV) interval prolongation (66 +/- 19 ms) compared with 2:1 AV block (44 +/- 6 ms, P < 0.01) and 1:1 AV conduction without bundle branch block (43 +/- 6 ms, P < 0.01)., Conclusion: The 2:1 AV block during AV nodal reentrant tachycardia is functional; the level of block is demonstrated to be within or below the His bundle in a majority of patients with 2:1 AV block during AV nodal reentrant tachycardia, and a minority are possibly high in the junction between the AV node and His bundle.

Aims: We investigated the predictive value of plasma concentration of asymmetrical dimethylarginine (ADMA) on clinical outcome in patients undergoing percutaneous coronary intervention (PCI)., Methods and Results: One-hundred and fifty-three consecutive patients with stable angina and undergoing PCI were prospectively enrolled for clinical follow-up. Plasma ADMA levels were determined before procedure by high performance liquid chromatography. The major adverse cardiovascular events included cardiovascular death, myocardial infarction, and repeat revascularization of target vessels. Patients were grouped into tertiles according to their plasma ADMA levels. Over a follow-up period of 16 months (median), cardiovascular events occurred in 6 patients of tertile I (<0.50microM), in 17 patients of tertile II (0.50-0.62microM), and in 28 patients of tertile III (>0.62microM), P<0.001. By multivariate analysis, tertiles of ADMA levels were independently associated with a higher risk of adverse cardiovascular events after PCI (relative risk: tertile II vs I: 3.0 [1.2-7.7], P=0.022; tertile III vs I: 5.3 [2.2-12.9], P<0.001). Moreover, plasma ADMA level in the highest tertile also appeared as a significant risk factor of subsequent death and non-fatal myocardial infarction after PCI (tertile III vs I, P=0.04)., Conclusion: Pre-procedural plasma ADMA levels may independently predict subsequent adverse cardiovascular events in patients undergoing PCI. Measurement of plasma ADMA levels could provide a rationale for risk stratification of patients by measuring ADMA levels before intervention.

The exact reentrant circuit of the verapamil-sensitive idiopathic left VT with a RBBB configuration remains unclear. Furthermore, if the fascicle of left bundle branch is involved in the reentrant circuit has not been well studied. Forty-nine patients with verapamil-sensitive idiopathic left VT underwent electrophysiological study and RF catheter ablation. Group I included 11 patients (10 men, 1 woman; mean age 25 +/- 8 years) with left anterior fascicular block (4 patients), or left posterior fascicular block (7 patients) during sinus rhythm. Group II included 38 patients (29 men, 9 women; mean age 35 +/- 16 years) without fascicular block during sinus rhythm. Duration of QRS complex during sinus rhythm before RF catheter ablation in group I patients was significant longer than that of group II patients (104 +/- 12 vs 95 +/- 11 ms, respectively, P=0.02). Duration of QRS complex during VT was similar between group I and group II patients (141 +/- 13 vs 140 +/- 14 ms, respectively, P=0.78). Transitional zones of QRS complexes in the precordial leads during VT were similar between group I and group II patients. After ablation, the QRS duration did not prolong in group I or group II patients (104 +/- 11 vs 95 +/- 10 ms, P=0.02); fascicular block did not occur in group II patients. Duration and transitional zone of QRS complex during VT were similar between the two groups, and new fascicular block did not occur after ablation. These findings suggest the fascicle of left bundle branch may be not involved in the antegrade limb of reentry circuit in idiopathic left VT.

Background: Asymmetrical dimethylarginine (ADMA) is an endogenous competitive inhibitor of nitric oxide synthase and has been associated with systemic atherosclerosis; however, the role of ADMA in patients with coronary artery disease (CAD) has not been investigated., Hypothesis: The present study was designed to determine whether the plasma ADMA level predicts the presence of CAD independently, and whether the plasma ADMA level correlates with the extent and severity of coronary atherosclerosis., Methods: In all, 97 consecutive patients with angina and positive exercise stress test were enrolled prospectively for coronary angiography. According to the result of angiography, the subjects were divided into two groups: Group I (n = 46): patients with normal coronary artery or mild CAD (< 50% stenosis of major coronary arteries); Group 2 (n = 51): patients with significant CAD (> or = 50% stenosis of majorcoronary arteries). Plasma levels of ADMA and L-arginine were determined by high-performance liquid chromatography. In addition, we used coronary atherosclerotic score to assess the extent and severity of CAD., Results: The plasma levels of ADMA in Group 2 patients were significantly higher than those in Group 1 patients (0.66 +/- 0.17 microM vs. 0.44 +/- 0.09 microM, p < 0.001); these were accompanied by significantly lower plasma L-arginine/ADMA ratio in patients with significant CAD (Group 1 vs. 2: 194.0 +/- 55.3 vs. 136.7 +/- 50.3, p < 0.001). In a multivariate stepwise logistic regression analysis, both plasma ADMA level and plasma L-arginine/ADMA ratio were identified as independent predictors for CAD. Moreover, there were significant positive and negative correlations between coronary atherosclerotic score and plasma ADMA level as well as plasma L-arginine/ADMA ratio, respectively (plasma ADMA level: r = 0.518, p < 0.001; L-arginine/ADMA ratio: r = -0.430, p < 0.001)., Conclusions: Both plasma ADMA level and plasma L-arginine/ADMA ratio were useful in predicting the presence of significant CAD and correlated significantly with the extent and severity of coronary atherosclerosis. Our findings suggest that plasma ADMA level may be a novel marker of CAD.

The importance of volume status on blood pressure in hemodialysis patients has long been recognized. We hypothesized that the enhanced volume dependency of blood pressure is partly determined by ventricular stiffness at end systole. A total of 115 long-term hemodialysis patients were invited to receive a comprehensive, noninvasive cardiovascular examination. End-systolic elastance was determined by using a novel, noninvasive echo-Doppler technique. The positive ratios of the interdialytic systolic blood pressure change vs weight gain during the subsequent 25 hemodialysis sessions were averaged to obtain the volume sensitivity index (mm Hg/kg). The averaged interdialytic weight gain per fat-free mass was correlated significantly with averaged percent change in systolic blood pressure (r=0.45, P<0.001). The estimated end-systolic elastance at baseline was significantly correlated with subsequently observed volume sensitivity index (volume sensitivity index=[1.17xend-systolic elastance]+6.4; r=0.34, P=0.001). End-systolic elastance was also significantly correlated with various vascular function parameters, including effective arterial elastance (r=0.48, P<0.001), pulse wave velocity (r=0.30, P=0.001), carotid augmentation index (r=0.31, P<0.001), and aortic compliance (r=-0.49, P<0.001). The results suggest that end-systolic elastance, a direct measure of left ventricular mechanical properties at end systole, is coupled to arterial mechanical properties and predicts the extent of subsequent interdialytic systolic blood pressure rise relative to weight gain. Therefore, ventricular stiffness at end systole is a determinant of the enhanced volume sensitivity of blood pressure in hemodialysis patients.

Background: Most of the ectopic beats initiating paroxysmal atrial fibrillation (PAF) originate from the pulmonary vein (PV). However, only limited data are available on PAF originating from the non-PV areas., Methods and Results: Two hundred forty patients with a total of 358 ectopic foci initiating PAF were included. Sixty-eight (28%) patients had AF initiated by ectopic beats (73 foci, 20%) from the non-PV areas, including the left atrial posterior free wall (28, 38.3%), superior vena cava (27, 37.0%), crista terminalis (10, 3.7%), ligament of Marshall (6, 8.2%), coronary sinus ostium (1, 1.4%), and interatrial septum (1, 1.4%). Catheter ablation eliminated AF with acute success rates of 63%, 96%, 100%, 50%, 100%, and 0% in left atrial posterior free wall, superior vena cava, crista terminalis, ligament of Marshall, coronary sinus ostium, and interatrial septum, respectively. During a follow-up period of 22+/-11 months, 43 patients (63.2%) were free of antiarrhythmic drugs without AF recurrence., Conclusions: Ectopic beats initiating PAF can originate from the non-PV areas, and catheter ablation of the non-PV ectopy has a moderate efficacy in treatment of PAF.

Introduction: High recurrence rate is still a major problem associated with ablation of paroxysmal atrial fibrillation (AF). Most of the recurrences occur within 6 months after ablation. The characteristics of very late recurrent AF (>12 months after ablation) have not been reported., Methods and Results: Two hundred seven patients with drug-refractory AF underwent successful focal ablation or isolation of AF foci. After the first ablation procedure, Holter monitoring and event recorders were used to evaluate symptomatic recurrent AF. A second ablation procedure was recommended if the antiarrhythmic drugs could not control recurrent AF. During long-term follow-up (mean 30 +/- 11 months, up to 51 months), 70 patients had recurrent AF, including 13 patients (6%) with very late (>12 months) recurrent AF (group 1) and 57 patients (28%) with late (within 12 months after ablation) recurrent AF (group 2). Group 1 patients had a significantly lower incidence of multiple (> or = 2) AF foci (23% vs 63%, P = 0.02) than group 2 patients. In addition, the incidence of antiarrhythmic drugs use (38% vs 84%, P = 0.001) to maintain sinus rhythm after the first episode of recurrent AF was significantly lower in group 1 than group 2 patients, and the incidence of a second intervention procedure (8% vs 35%, P = 0.051) tended to be lower in group 1 than group 2 patients., Conclusion: The incidence of very late recurrent AF after ablation of paroxysmal AF is very low, and the clinical outcome of patients with very late recurrent AF is benign.

Introduction: Information about the activation patterns inside the superior vena cava (SVC) and entry and exit sites at the SVC-right atrial (RA) junction during SVC tachyarrhythmia is limited., Methods and Results: A detailed characterization of electrophysiologic mechanisms and ablation strategies was performed using a noncontact three-dimensional mapping system in two cases of SVC tachycardia. The first case demonstrated SVC tachycardia originating from an ectopic focus inside the SVC, with sustained depolarization and conduction to the atrium. Entry and exit sites across the SVC-RA junction were located very close to each other. The second case demonstrated two different reentrant circuits, one inside the SVC and the other into and out of the SVC-RA junction. The entry and exit sites were located far away from each other., Conclusion: Noncontact mapping may help to reveal the mechanism of SVC tachyarrhythmias and to locate entry and exit sites at the SVC-RA junction as a guide for catheter ablation.

Introduction: The superior vena cava (SVC) and right superior pulmonary vein (RSPV) are anatomically close structures. Using 12-lead ECG may facilitate identification of ectopic foci from SVC or RSPV. The aim of this study was to assess whether P wave polarity on surface ECG is helpful in distinguishing an arrhythmogenic focus of paroxysmal atrial fibrillation (AF) from SVC or RSPV., Methods and Results: Thirty-four patients with paroxysmal AF from the SVC (group I: 17 patients, 10 men and 7 women; mean age 57 +/- 12 years) or RSPV (group II: 17 patients, 15 men and 2 women, mean age 62 +/- 14 years) underwent electrophysiologic study and radiofrequency (RF) catheter ablation. All of the AF foci were confirmed by successful ablation. P wave polarities on surface ECG inferior leads were positive during sinus rhythm and ectopic beats in both groups. Leads I, aVR, aVL, and V1 were further analyzed. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) in predicting an arrhythmogenic focus of AF from SVC or RSPV were provided. P wave polarity in lead aVR was negative in all 34 patients. P wave polarity in lead V1 was positive in 47.1% of SVC ectopy but positive in all RSPV ectopy. The combination of a biphasic or isoelectric P wave polarity in lead V1 or a biphasic P wave polarity in lead aVL had a sensitivity of 71%, specificity of 82%, PPV of 80%, and NPV of 74% in predicting an arrhythmogenic focus of AF from SVC., Conclusion: P wave polarity in leads V1 and aVL may predict an arrhythmogenic focus of AF from SVC or RSPV.

The average rate of fibrillatory activity may reflect the global activation pattern of AF. Electrical cardioversion is the most effective method of converting chronic AF to sinus rhythm. The aim of this study was to investigate the relation between the minimal defibrillation energy requirement and the dominant frequency of chronic AF. Twenty-nine patients with chronic AF (mean duration 57.9 +/- 7.7 months) underwent external electrical cardioversion. Before cardioversion, the frequency content of the 60-second AF in ECG lead V1 was quantified using digital signal processing. After band-pass filtering, QRST complexes were cancelled using a recursive lease squares algorithm. The resulting fibrillatory baseline signal was subjected to fast Fourier transform and was displayed as a power spectrum. The dominant AF frequency was found to range from 4.9 to 8.7 Hz (mean 6.7 +/- 0.9 Hz). Twenty-six patients had successful conversion of AF to sinus rhythm without immediate recurrence. There was a positive correlation between the minimal defibrillation energy and the dominant frequency of chronic AF (rho = 0.414, P = 0.035). Thus, power spectral analysis of AF using the surface ECG is feasible and may be useful in predicting the minimal shock energy required for successful cardioversion of chronic AF.

Introduction: Radiofrequency catheter ablation of the cavotricuspid isthmus is an effective therapy for typical atrial flutter (AFL), however, the long-term recurrence of AFL and early or late occurrence of atrial fibrillation (AF) are not well defined. This study investigated the long-term (up to 68 months) outcome of patients with typical AFL after catheter ablation of the cavotricuspid isthmus., Methods: This study included 380 patients with typical AFL, who received linear ablation of the cavotricuspid isthmus. They were followed up at the outpatient clinic. A questionnaire was used to evaluate the symptoms suggestive of tachyarrhythmias, and 12-lead ECG, Holter monitoring and event recorders were used to confirm the diagnosis of tachyarrhythmias., Results: At the end of study, 47 patients lost follow-up, so that 333 patients were enrolled into final analysis. Ten (3%) patients had failed ablation of typical AFL. Univariate analysis showed that left atrial dimension was the only factor related to failed ablation. During the long-term follow-up period of 29 +/- 17 months (range 7 to 68 months), 29 (9%) patients had recurrent AFL, including 15 with typical and 14 with atypical AFL. Univariate and multivariate analyses showed that incomplete isthmus block and inducible atypical AFL were the independent predictors of recurrent typical and atypical AFL, respectively. One hundred and two (31%) patients developed AF, including 48 with early occurrence of AF (within 3 months after ablation), and 54 with late occurrence of AF (greater than 3 months). Univariate and multivariate analyses showed that prior history of AF and inducible AF were independent predictors of early occurrence of AF, and prior history of AF was the only independent predictor of late occurrence of AF., Conclusions: Linear ablation of the cavotricuspid isthmus is an effective therapy with low recurrence rate for patients with typical AFL. However, one-third patients had early or late occurrence of AF.

The aim of the study was to define the factors that may predict the outcomes of radiofrequency ablation from the right ventricular outflow tract (RVOT) in patients with idiopathic VT with a QRS morphology of LBBB. Endocardial mapping and RF ablation from the RVOT were performed in 35 patients (14 men, mean age 41 +/- 14 years), and VT was successfully ablated in 30 patients. There was no significant difference with regard to clinical characteristics and electrophysiological findings between patients with successful and failed ablation. The VTs with successful ablation showed an rS (n = 16) or QS (n = 14) pattern in lead V1, and all five VTs with failed ablation showed an rS pattern in lead V1. Although the absence of an R wave in lead V1 did not differ between patients with successful and failed ablation (P = 0.13), the absence of an R wave in lead V1 predicted VT successfully ablated from the RVOT (positive predictive value 100%; negative predictive value 24%). The VTs with successful ablation had a median precordial transitional zone at lead V4 (range V3-V6), whereas all five VTs with failed ablation had precordial transition zones at lead V3 (P = 0.004). Furthermore, a presence of an R wave in lead V1 associated with a precordial transition zone at lead V3 predicted VT not successfully ablated from the RVOT (positive predictive value 100%; negative predictive value 100%). In conclusion, some VTs with LBBB and inferior or normal axis cannot be ablated from the RVOT. The presence of an R wave in lead V1 associated with a precordial transition zone at lead V3 suggest that some VTs may not arise from the RVOT.

Objectives: This study was aimed at delineating the reentrant circuit of right atrial (RA) upper loop re-entry using noncontact three-dimensional mapping., Background: Various forms of atypical atrial flutter including lower loop re-entry and left atrial flutter have been demonstrated. However, little is known about upper loop re-entry in the RA., Methods: The study population consisted of eight patients (65 +/- 12 years, seven men) with atypical atrial flutter. Right atrial activation during atrial flutter was visualized using a noncontact mapping system (EnSite-3000 with Clarity Software, St. Paul, Minnesota) for a three-dimensional reconstruction of the endocardial depolarization. The narrowest part of the re-entrant circuit was targeted using radiofrequency catheter ablation., Results: Noncontact mapping showed macro-re-entry confined to the RA free wall with RA activation time accounting for 100% of the cycle length (214 +/- 21 ms) in all eight patients. Two patients had counterclockwise activation, and six patients had clockwise activation around the central obstacle, which was composed of the crista terminalis, the area of functional block, and superior vena cava. The lower turn-around points were located at the conduction gap in the crista terminalis. Radiofrequency linear ablation of the conduction gap in the crista terminalis was performed and eliminated atrial flutter in six patients without recurrence during a follow-up of 3.2 +/- 1.1 months., Conclusions: Atypical atrial flutter could arise from upper loop re-entry in the RA with conduction through the gap in the crista terminalis. Radiofrequency linear ablation of the conduction gap was effective in eliminating this atrial arrhythmia.

Background: Complete bi-directional isthmus block is the endpoint of typical atrial flutter ablation. The purpose of this study was to investigate the feasibility of the local double potential (DP) interval and the change in transisthmus conduction time for predicting complete isthmus block after ablation of the cavotricuspid isthmus., Methods: The study population consisted of 32 patients with typical atrial flutter after a procedure of radiofrequency (RF) ablation of the cavotricuspid isthmus (16 had incomplete block and 16 had complete block). The transisthmus conduction time was determined during pacing from the proximal coronary sinus and low lateral right atrium before and after RF ablation. The DP interval close to the ablation line was evaluated after final RF energy application., Results: In the counterclockwise direction, transisthmus conduction time had an increase of 37 +/- 25.4% and 127.3 +/- 35.5% (P < 0.001), and the DP interval was 63.3 +/- 8.7 ms and 120 +/- 17.4 ms (P < 0.001) after achievement of incomplete and complete block, respectively. The sensitivity, specificity, positive and negative predictive values of an increase in the transisthmus conduction time > or =50% were 100%, 81%, 84% and 100%, respectively; those of DP interval > or =100 ms were 100%. In the clockwise direction, transisthmus conduction time had an increase of 38.8 +/- 28.6% and 135.7 +/- 63.6% (P < 0.001), and the DP interval was 63.6 +/- 13.8 ms and 127.7 +/- 27.1 ms (P < 0.001) after achievement of incomplete and complete block, respectively. The sensitivity, specificity, positive and negative predictive values of an increase in the transisthmus conduction time > or =50% were 100%, 67%, 83% and 100%, respectively; those of the DP interval > or =100 ms were 100%., Conclusions: The transisthmus conduction time > or =50% increase or DP interval > or =100 ms was feasible to predict complete bi-directional isthmus block.

Heme oxygenase is a rate-limiting enzyme in heme degradation, leading to the generation of free iron, biliverdin, and carbon monoxide. Induction of heme oxygenase-1 is implicated in the antioxidant defense mechanism and can modulate vascular function. To test the association of microsatellite polymorphism in the promoter region of human HO-1 gene with the risk of coronary artery disease (CAD) in type 2 diabetic patients, we examined the allele frequencies of (GT) (n) repeats in HO-1 gene in 474 patients with CAD and in 322 controls. A transient-transfection assay with HO-1 promoter/luciferase fusion constructs carrying various lengths of (GT) (n) repeats was performed to explore the regulatory effect of (GT) (n) repeats on HO-1 gene expression in cultured rat aortic smooth muscle cells. Serum thiobarbituric acid-reactive substances (TBARs), a measure of lipid peroxidation, was significantly higher in subjects carrying the L/L genotype (> or =32 repeats). Among type 2 diabetic subjects, the frequencies of the L alleles and proportion of genotypes with L alleles were significantly higher in those with CAD than in those without CAD. The adjusted odds ratio for CAD in type 2 diabetic patients with L alleles was 4.7 (95% confidence interval, 1.9-12.0, P=0.001). Transfection experiments in aortic smooth muscle cells revealed that HO-1 promoter/luciferase fusion constructs containing longer (GT) (n) repeats exhibited lower transcriptional activity. These results imply that the length polymorphism in the HO-1 gene promoter modulate the transcription of the gene in vascular cells. Type 2 diabetics carrying longer (GT) (n) repeats might have higher oxidative stress and increased susceptibility to the development of CAD.

Background: The efficacy and safety of the new statin, cerivastatin, in the Chinese patients with primary hypercholesterolemia remains to be determined., Methods: In this prospective, double-blind, parallel-group study, patients with primary hypercholesterolemia were randomized to treatment with cerivastatin, 0.3 mg (n = 21) or lovastatin, 20 mg (n = 22), for 8 weeks. The primary efficacy variable was percentage change of low-density lipoprotein (LDL) cholesterol from baseline. The secondary efficacy variables were percentage change of total cholesterol, triglycerides and high-density lipoprotein (HDL) cholesterol. RESULTS.:Both cerivastatin and lovastatin effectively reduced LDL cholesterol (-33.2% vs. -29.3%, p = 0.63), total cholesterol (-25% vs. -20%, p = 0.10), and triglycerides (-21% vs. -14%,p = 0.27) (all p < 0.0001 for comparison with baseline), and slight increased HDL cholesterol (+2% vs. +8%, p = 0.008) over the 8-week treatment period. The LDL cholesterol responsive rates according to the recommendations from the National Cholesterol Educational Panel (NCEP) were 43% and 32% for cerivastatin and lovastatin, respectively. The adverse event profiles of cerivastatin and lovastatin were similar., Conclusions: Cerivastatin 0.3 mg once daily is as effective and safe as lovastatin 20 mg once daily in lowering LDL and total cholesterol in Chinese patients with primary hypercholesterolemia.