Acute Kidney Injury ; epidemiology ; Biomedical Research ; statistics & numerical data ; China ; epidemiology ; Humans

Aged ; Coronary Disease ; complications ; Humans ; Hypertension ; complications ; Renal Artery Obstruction ; diagnosis ; Renal Insufficiency ; complications ; Risk Factors

BACKGROUNDIntegrin-linked kinase (ILK) dysregulation is involved in the progression of diabetic nephropathy (DN). The aim of this study was to investigate the effects of angiotensin II receptor blocker (ARB), irbesartan, on ILK expression and podocyte injury in DN.

METHODSDN was induced by the combined feeding of high-sucrose, high-fat diet and intra-peritoneal injection of low dose of streptozotocin (35 mg/kg) in spontaneously hypertensive rats. Diabetic rats were treated with irbesartan (50 mg×kg(-1)×d(-1)) by gavage for 8 weeks. The renal morphologic changes and podocyte injury were investigated by light and electron microscopy, and the ILK expression was evaluated by real-time RT-PCR and Western blotting analysis.

RESULTSDiabetic rats exhibited with the similar clinical feature of type 2 DN. Morphologically, they were characterized by expansion of mesangial matrix, loss of podocyte and podocyte injury. Impressively, compared to controls, the ILK expression in diabetic rats were upregulated, which were positively correlated with both podocyte injury and albuminuria. Irbesartan significantly prevented ILK overexpression, along with the amelioration of podocyte injury and albuminuria.

CONCLUSIONSILK plays an important role in mediating podocyte injury in DN; irbesartan inhibits ILK upregulation and attenuates podocyte injury, which might offer a new insight into the role of ARB in preventing DN progression.

Angiotensin Receptor Antagonists ; therapeutic use ; Animals ; Biphenyl Compounds ; therapeutic use ; Diabetes Mellitus, Experimental ; drug therapy ; metabolism ; Enzyme Activation ; drug effects ; Male ; Podocytes ; drug effects ; Protein-Serine-Threonine Kinases ; metabolism ; Rats ; Rats, Inbred SHR ; Tetrazoles ; therapeutic use

BACKGROUNDExtensive atrial fibrillation (AF) ablation is associated with an increased success rate of catheter ablation in chronic AF patients and an increased rate of atrial tachycardia (AT) during the procedure. The mechanism of these ATs varies in previous studies. Our study aimed to report the mechanism of organized AT occurring during the stepwise ablation procedure of chronic AF.

METHODSA prospective cohort of 86 consecutive patients who underwent an ablation procedure for chronic atrial fibrillation (CAF) was investigated. The stepwise procedure was performed in the following order: circumferential pulmonary vein ablation, complex fractionated atrial electrograms ablation, mapping and ablation of AT. The endpoint was noninducibility of AF/AT after sinus rhythm (SR) was restored or the procedure time was beyond 6 hours.

RESULTSSixty-nine (80%) of patients converted to SR via AT. A total of 179 sustained ATs were observed in 69 patients during the procedure. There were 81% (n = 145) macroreentrant ATs which included 65 perimitral circuits, 48 peritricuspid tachycardia and 32 roof dependent circuits, 12% (n = 21) localized reentrant and 7% (n = 13) focal ATs. Thirty (15%) patients experienced significant left atrium (LA) and LA appendage (LAA) conduction delay or dissociation in the procedure or during the follow-up period.

CONCLUSIONSMost CAF patients converted to SR via ablation of organized AT occurring during the stepwise procedure. The mechanism of most of these ATs was macro-reentry.

Aged ; Atrial Fibrillation ; surgery ; Catheter Ablation ; methods ; Electrophysiology ; Female ; Humans ; Male ; Middle Aged ; Prospective Studies ; Tachycardia, Ectopic Atrial ; surgery ; Treatment Outcome

BACKGROUNDThe optimal endpoint for catheter ablation of persistent atrial fibrillation (AF) remains ambiguous. This study investigated the impact of AF termination as a procedural endpoint and the termination mode on long-term clinical outcome.

METHODSTwo hundred and ninety-three patients who underwent stepwise ablation for persistent AF were categorized into the AF termination by ablation group and into the electrical cardioversion (CV) group. Subgroups were also analyzed based on different termination modes. Follow-up assessment included early recurrence and sinus rhythm (SR) maintenance.

RESULTSDuring initial ablation, 33 patients (11.3%) were directly converted to SR, 166 patients (56.7%) were converted to atrial tachycardia (AT) that subsequently restored SR with further ablation in 98 patients (33.4%), and a total of 162 patients (55.3%) underwent cardioversion due to persistent atrial arrhythmias. Comparison between termination by ablation and termination by cardioversion in patients exhibiting AF or AT revealed that no significant difference was observed in early recurrence (38.2% vs. 43.8%, P = 0.328) and SR maintenance (67.2% vs. 59.8%, P = 0.198) during the (23 ± 7) months follow-up. Even after repeat ablation, the SR maintenance continued to exhibit no statistical difference in above two groups (72.5% vs. 70.4%, P = 0.686). Further analysis of subgroups, however, demonstrated that patients with AF terminated directly to SR experienced better clinical outcomes than other subgroups (P < 0.05). Furthermore, atrial arrhythmias present during ablation have been implicated in prediction of recurrence mode: AF or AT (P < 0.05).

CONCLUSIONSTermination as a procedural endpoint is not associated with favorable long-term SR maintenance in persistent AF. AF methods that convert arrhythmia directly to SR have, however, been linked with improved clinical outcomes, although conversions to AT may not be correlated. Atrial arrhythmias observed during the ablation may be used to predict the recurrence mode.

Adult ; Aged ; Atrial Fibrillation ; physiopathology ; therapy ; Catheter Ablation ; methods ; Electrophysiologic Techniques, Cardiac ; Female ; Humans ; Male ; Middle Aged

BACKGROUNDRadiofrequency (RF) ablation has become a widely accepted treatment for atrial fibrillation (AF). This study aimed to identify the efficacy and safety of pulmonary vein (PV) ablation with ethanol and to explore an alternative energy source for catheter ablation of AF.

METHODSTwelve open-chest mongrel dogs were randomized into ethanol ablation group and control group. Both the injections and electrophysiological mapping procedures were performed epicardialy. In ethanol ablation group (n = 6), injections were performed to circumferentially ablate the root of each PV (0.2 ml each site, 3 mm apart) with 95% ethanol using an 1 ml injector. In control group (n = 6), saline was injected other than ethanol. PV isolation was confirmed with a circular catheter immediately after the procedure and at follow up of 30 days. PV isolation was defined as the absence of PV potentials at each electrode of the circular catheter positioned at the PV side of the lesions, as well as complete conduction block into left atrium (LA) during PV pacing.

RESULTSPV electrical isolation with complete bidirectional conduction block was achieved with ethanol immediately and at 30 days in 95% of PVs, while saline injection caused only transient conduction changes between LA and PVs. In ethanol group, histologic analysis showed transmural lesions at 30 days. And there was no evidence of PV stenosis or thrombus formation. Mean LA diameter was not significantly different between baseline and 30 days.

CONCLUSIONEthanol is a safe energy source to effectively isolate PV in canine model and may be promising in endocardial ablation procedure of AF patients in the future.

Animals ; Catheter Ablation ; methods ; Dogs ; Electrophysiology ; Ethanol ; Pulmonary Veins ; physiology ; surgery ; Random Allocation

BACKGROUNDCatheter ablation for atrial fibrillation (AF) has been demonstrated to be effective in a subsets of patients with AF. However, very few data are available in regard to patients with prior history of stroke undergoing catheter ablation. This study aimed to investigate the outcome of catheter ablation in AF patients with prior ischemic stroke.

METHODSBetween January 2008 and December 2011, of 1897 consecutive patients who presented at Beijing An Zhen Hospital for treatment of drug-refractory AF, 172 (9.1%) patients in the study population had a history of ischemic stroke. All patients underwent catheter ablation and were followed up to assess maintenance of sinus rhythm and recurrence of symptomatic stroke.

RESULTSAmong these 1897 patients, 1768 (93.2%) who had complete follow-up information for a minimum of six months were included in the final analysis. Patients in the stroke group (group I) and the no-stroke group (group II) were similar in regards to gender, body mass index (BMI), history of diabetes, type of AF, and left atrial size. The patients in group I were older than those in group II, and had a higher incidence of hypertension, chronic heart failure, lower left ventricular ejection fraction (LVEF), and higher CHADS2 scores. Six months after ablation, 107 (68.6%) patients in group I and 1403 (87.1%) in group II had discontinued warfarin treatment (P < 0.001). During a median follow-up of (633 ± 415) days, 65 patients in the group I and 638 in group II experienced AF recurrence, and five patients in group I and 28 in group II developed symptomatic stroke. The rates of AF recurrence and recurrent stroke were similar between group I and group II (41.7% vs. 39.6%, P = 0.611; 3.2% vs. 1.7%, P = 0.219; respectively).

CONCLUSIONCatheter ablation of AF in patients with prior stroke is feasible and efficient.

Aged ; Atrial Fibrillation ; surgery ; Catheter Ablation ; methods ; Female ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Stroke ; surgery

Atrial Fibrillation ; surgery ; Cardiac Tamponade ; etiology ; surgery ; Catheter Ablation ; adverse effects ; Female ; Humans ; Male ; Middle Aged

BACKGROUNDHATCH score is an established predictor of progression from paroxysmal to persistent atrial fibrillation (AF). The purpose of this study was to determine if HATCH score could predict recurrence after catheter ablation of AF.

METHODSThe data of 488 consecutive paroxysmal AF patients who underwent an index circumferential pulmonary veins (PV) ablation were retrospectively analyzed. Of these patients, 250 (51.2%) patients had HATCH score = 0, 185 (37.9%) patients had HATCH score = 1, and 53 (10.9%) patients had HATCH score ≥ 2 (28 patients had HATCH score = 2, 23 patients had HATCH score = 3, and 2 patients had HATCH score = 4).

RESULTSThe patients with HATCH score ≥ 2 had significantly larger left atrium size, the largest left ventricular end systolic diameter, and the lowest ejection fraction. After a mean follow-up of (823 ± 532) days, the recurrence rates were 36.4%, 37.8% and 28.3% from the HATCH score = 0, HATCH score = 1 to HATCH score ≥ 2 categories (P = 0.498). Univariate analysis revealed that left atrium size, body mass index, and failure of PV isolation were predictors of AF recurrence. After adjustment for body mass index, left atrial size and PV isolation, the HATCH score was not an independent predictor of recurrence (HR = 0.92, 95% confidence interval = 0.76 - 1.12, P = 0.406) in multivariate analysis.

CONCLUSIONHATCH score has no value in prediction of AF recurrence after catheter ablation.

Adult ; Aged ; Atrial Fibrillation ; therapy ; Body Mass Index ; Catheter Ablation ; methods ; Electrophysiology ; Female ; Humans ; Kaplan-Meier Estimate ; Male ; Middle Aged

Humans ; Mutation ; NAV1.5 Voltage-Gated Sodium Channel/genetics*