A novel method for precise implantation of tracheal Y-shaped stent.

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.

Dynamic Transcriptome Profiling Reveals LncRNA-Centred Regulatory Networks in the Modulation of Pluripotency.

Long noncoding RNAs (lncRNAs) have emerged as vital regulators of gene expression during embryonic stem cell (ESC) self-renewal and differentiation. Here, we systemically analyzed the differentially regulated lncRNAs during ESC-derived cardiomyocyte (CM) differentiation. We established a perspicuous profile of lncRNA expression at four critical developmental stages and found that the differentially expressed lncRNAs were grouped into six distinct clusters. The cluster with specific expression in ESC enriches the largest number of lncRNAs. Investigation of lncRNA-protein interaction network revealed that they are not only controlled by classic key transcription factors, but also modulated by epigenetic and epitranscriptomic factors including N6-methyladenosine (m6A) effector machineries. A detailed inspection revealed that 28 out of 385 lncRNAs were modified by methylation as well as directly recruited by the nuclear m6A reader protein Ythdc1. Unlike other 27 non-coding transcripts, the ESC-specific lncRNA Gm2379, located in both nucleus and cytoplasm, becomes dramatically upregulated in response to the depletion of m6A or Ythdc1. Consistent with the role of m6A in cell fate regulation, depletion of Gm2379 results in dysregulated expressions of pluripotent genes and crucial genes required for the formation of three germ layers. Collectively, our study provides a foundation for understanding the dynamic regulation of lncRNA transcriptomes during ESC differentiation and identifies the interplay between epitranscriptomic modification and key lncRNAs in the regulation of cell fate decision.

Factors associated with behavior modification for cardiovascular risk factors in patients with coronary artery disease in northern Taiwan.

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.

Effects of fluvastatin, an HMG-CoA reductase inhibitor, on serum levels of interleukin-18 and matrix metalloproteinase-9 in patients with hypercholesterolemia.

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.

Electrophysiological mechanisms and catheter ablation of complex atrial arrhythmias from crista terminalis:.

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.

Effect of rosuvastatin on plasma levels of asymmetric dimethylarginine in patients with hypercholesterolemia.

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.

Predictors of early and late recurrence of atrial fibrillation after catheter ablation of paroxysmal atrial fibrillation.

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.

Functional characterization of the crista terminalis in patients with atrial flutter: implications for radiofrequency ablation.

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.

High-resolution mapping around the crista terminalis during typical atrial flutter: new insights into mechanisms.

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.

Focal atrial tachycardia: new insight from noncontact mapping and catheter ablation.

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.

Conduction properties of the crista terminalis in patients with atrial flutter due to amiodarone therapy for atrial fibrillation.

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.

Spontaneous transition of 2:1 atrioventricular block to 1:1 atrioventricular conduction during atrioventricular nodal reentrant tachycardia: evidence supporting the intra-Hisian or infra-Hisian area as the site of block.

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.

Use of fluoroscopic views for detecting Marshall's vein in patients with cardiac arrhythmias.

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.

Is the fascicle of left bundle branch involved in the reentrant circuit of verapamil-sensitive idiopathic left ventricular tachycardia?

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.

Asymmetrical dimethylarginine: a novel risk factor for coronary artery disease.

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.

Plasma levels of asymmetrical dimethylarginine and adverse cardiovascular events after percutaneous coronary intervention.

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.

Clinical outcome of very late recurrence of atrial fibrillation after catheter ablation of paroxysmal atrial fibrillation.

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.