Shih-Lin Chang

Taipei Veterans General Hospital, T’ai-pei, Taipei, Taiwan

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Publications (207)751.54 Total impact

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    ABSTRACT: Introduction: Heart failure (HF) increases the susceptibility to atrial fibrillation (AF) and is associated with altered cardiomyocyte connexin. The regional remodeling of connexin(s) may contribute to the spatiotemporal organization of AF. This study sought to investigate the regional differences in connexin(s) and fibrosis in specific atrial regions and correlate that with the electrogram properties. Methods and results: Biatrial electroanatomic mapping during sinus rhythm (electrogram voltage and velocity) and AF (dominant frequency, DF) was performed in 6 ventricular pacing-induced HF dogs (at 252 beats/minute for 6 weeks) and 6 controls. Atrial tissues were sampled from 7 specific sites for analysis of the connexin and fibrosis. HF caused marked atrial dilatation, and increased the induced AF duration (P < 0.001). Remodeled connexins, including a lower expression and more lateralization of both connexin40 (Cx40) and Cx43 as well as increased regional dispersion of Cx40, in the presence of diffuse enhanced atrial fibrosis, characterized the atrial substrate of the HF dogs (P < 0.01). Regional analysis showed abnormal velocity and low electrogram voltage in the areas with downregulated Cx40 and Cx43 was enhanced in the presence of marked atrial fibrosis (>30% of area, P < 0.01). During AF, lower expression of the Cx40 was associated with higher DF in areas of less and more fibrosis, respectively (R = 0.67 and 0.58, P < 0.01). Conclusions: An altered expression of connexins correlated with the electrogram properties in the existence of diffuse enhanced atrial fibrosis associated with HF. The regional remodeling of Cx40 is likely an important factor in the maintenance of AF in HF.
    No preview · Article · Jan 2013 · Journal of Cardiovascular Electrophysiology
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    ABSTRACT: Background: The components of CHADS2 score were reported to be important risk factors for the development of atrial fibrillation (AF). The goal of the current study was to investigate whether the CHADS2 score was a useful scheme in predicting new-onset AF. Furthermore, we aimed to use the CHADS2 scoring system to estimate the individual risk in developing AF for patients with different comorbidities. Methods: From January 1, 2000 to December 31, 2001, a total of 702,502 patients older than 18 years old and who had no history of cardiac arrhythmias were identified from the "National Health Insurance Research Database" released by the Taiwan National Health Research Institutes. The CHADS2 score was calculated for every patient. Finally, 628,807 (score 0), 47,039 (score 1), 15,655 (score 2), 6843 (score 3), 3315 (score 4), 790 (score 5) and 53 (score 6) patients were studied and followed for the occurrences of AF. Results: During a follow-up of 9.0 ± 2.2 years, there were 9187 (1.3%) patients experiencing new-onset AF. The incidence of AF was 1.5 per 1000 patient-years. The incidence increased from 0.8 per 1000 patient-years for patients with a CHADS2 score of 0 to 34.6 per 1000 patient-years for those with a CHADS2 score of 6. After an adjustment for the gender and comorbidities, the hazard ratio (95% confidence interval) of each increment of the CHADS2 score in predicting AF was 2.342 (2.309-2.375; p<0.001). Conclusions: The CHADS2 score, consisting of an age >75 and several clinical risk factors was useful in risk estimation and stratification of new-onset AF.
    No preview · Article · Dec 2012 · International journal of cardiology
  • Yenn-Jiang Lin · Shih-Lin Chang · Li-Wei Lo · Shih-Ann Chen
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    ABSTRACT: Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice. In recent years, growing knowledge of atrial substrate mapping has helped us to characterize atrial substrate. In clinical mapping, individual knowledge of sinus rhythm activity may help in identification of mechanism and the critical targets for AF. In this review chapter, we firstly focus on three-dimensional (3D) mapping techniques in time-domain electrogram and frequency-domain spectra from intracardiac recording. Secondly, we focus on substrate mapping has helped to depict the sequence of the activation time, electrogram voltage and electrogram characteristic during sinus rhythm (SR), in detecting substrate abnormality, potential sinus node dysfunction and slow-conduction area or scar. Lastly, we focus on spectral analysis is to elucidate the data beyond the time-domain electrogram. Spectral analysis during SR also provides information regarding abnormal arrhythmogenic substrate and may indicate the parasympathetic innervation sites. These may be helpful for the understanding of AF.
    No preview · Chapter · Dec 2012
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    ABSTRACT: The present study investigated the incidence and predictors of permanent pacemaker (PPM) implantation for late atrioventricular block (AVB) in patients with atrioventricular nodal reentrant tachycardia (AVNRT) who received ablation. The data from 3,442 patients with AVNRT who received ablation were analyzed. Those who developed late AVB (>1 month after ablation) and received a PPM were identified. The incidence of PPM implantation in 1,148 matched patients with Wolff-Parkinson-White syndrome and in the whole population of Taiwan were compared. Of the patients with AVNRT receiving ablation (mean follow-up duration 128.3 ± 62.5 months), 15 (0.4%) received PPM implantation for late AVB (mean interval after catheter ablation 95.4 ± 55.0 months). Only age (odds ratio 1.05, p = 0.02) and transient AVB (odds ratio 8.55, p = 0.01) during the procedure were independently associated with PPM implantation for late AVB. The patients with AVNRT had a greater incidence of PPM implantation due to late AVB compared to the matched patients with Wolff-Parkinson-White syndrome. The annual incidence of PPM implantation for AVB was also greater in the patients with AVNRT than in the general population. In conclusion, the incidence of PPM implantation for late AVB in patients with AVNRT who received catheter ablation was low but still greater than that in patients with Wolff-Parkinson-White syndrome and the general population in Taiwan.
    Full-text · Article · Dec 2012 · The American journal of cardiology
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    ABSTRACT: AIMS: It is not known if successful catheter ablation for atrial fibrillation (AF) improves the patient's long-term cardiovascular outcomes. This study investigated the long-term outcomes and mortality of AF patients at high risk who received antiarrhythmic medication and catheter ablation.METHODS AND RESULTS: The propensity scores for AF were calculated for each patient and were used to assemble a cohort of 174 AF patients with ablation who were compared with an equal number of AF patients without ablation. Composite cardiovascular end points (major adverse cardiovascular event, MACE), including mortality and vascular events in the medically treated patients representing the control group (group 1), were compared with those in the ablation-treated patients (group 2). The rates of the total mortality (2.95% vs. 0.74% per year; P < 0.01), cardiovascular death (1.77% vs. 0% per year; P = 0.001), and ischaemic stroke/transient ischaemic attack (2.21% vs. 0.59% per year; P = 0.02) were higher in group 1 than group 2, respectively. A multivariate Cox regression analysis of the MACE scores showed that a higher CHA(2)DS(2)-VASc score [hazard ratio (HR) = 1.309 per increment of score, 95% confidence interval (CI) = 1.06-1.617; P = 0.01] and the performance of the ablation procedure (HR = 0.225, CI = 0.076-0.671; P = 0.007) were independent predictors of a MACE. In patients who received catheter ablation, recurrence of any atrial arrhythmia was a predictor of vascular events and total mortality (P < 0.05).CONCLUSION: In AF patients with CHA(2)DS(2)-VASc score ≥1, catheter ablation of AF reduced the risk of the total/cardiovascular mortality and total vascular events. Atrial fibrillation recurrence predicts long-term cardiovascular outcomes, as well as the CHA(2)DS(2)-VASc score.
    No preview · Article · Nov 2012 · Europace
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    ABSTRACT: Electromechanical Interval and Strokes After Ablations of AF. Introduction: Atrial fibrillation (AF) is associated with increased risk of embolic stroke. Catheter ablation of AF provides an effective therapy for patients with symptomatic and drug-refractory AF. The aim of this study was to evaluate whether the atrial electromechanical interval is useful in identifying patients at risk of stroke after successful catheter ablation. Methods and Results: A total of 279 AF patients who received catheter ablation and showed no evidence of recurrences were enrolled. Electromechanical interval (PA–PDI) was determined as the time interval from the initiation of P wave deflection to the peak of mitral inflow A wave on pulse wave Doppler imaging. The PA–PDI interval was measured for each patient after the 3-month blanking period of catheter ablation. The clinical endpoint was the occurrence of ischemic stroke. During the follow-up of 46.5 ± 17.2 months, 6 patients suffered from ischemic strokes. Patients with strokes had higher CHA2DS2–VASc scores and longer PA–PDI intervals (138.7 ± 12.4 ms vs 161.2 ± 7.7 ms, P value < 0.001) compared to those without strokes. At a cutoff point of 150 ms identified by ROC curve, the positive and negative predictive values of the PA–PDI interval to predict stroke were 86.7% and 100%, respectively. The PA–PDI interval improved the predictive performance of the CHA2DS2–VASc score, and the area under the ROC curve increased from 0.75 to 0.85. Conclusions: Our results suggest that the PA–PDI interval is a useful tool to identify patients with high risk of stroke after successful catheter ablation of AF. (J Cardiovasc Electrophysiol, Vol. 24, pp. 375-380, April 2013)
    No preview · Article · Nov 2012 · Journal of Cardiovascular Electrophysiology
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    ABSTRACT: Nonlinear Analysis of Atrial Fibrillation. Introduction: Currently, the identification of complex fractionated atrial electrograms (CFEs) in the substrate modification is mostly based on cycle length-derived algorithms. The characteristics of the fibrillation electrogram morphology and their consistency over time are not clear. The aim of this study was to optimize the detection algorithm of crucial CFEs by using nonlinear measure electrogram similarity. Methods and Results: One hundred persistent atrial fibrillation patients that underwent catheter ablation were included. In patients who required CFE ablation (79%), the time-domain fibrillation signals (6 seconds) were acquired for a linear analysis (mean fractionation interval and dominant frequency [DF]) and nonlinear-based waveform similarity analysis of the local electrograms, termed the similarity index (SI). Continuous CFEs were targeted with an endpoint of termination. Predictors of the various signal characteristics on the termination and clinical outcome were investigated. Procedural termination was observed in 39% and long-term sinus rhythm maintenance in 67% of the patients. The targeted CFEs didn't differ based on the linear analysis modalities between the patients who responded and did not respond to CFE ablation. In contrast, the average SI of the targeted CFEs was higher in termination patients, and they had a better outcome. Multivariate regression analysis showed that a higher SI independently predicted sites of termination (≥0.57; OR = 4.9; 95% CI = 1.33–18.0; P = 0.017). Conclusions: In persistent AF patients, a cycle length-based linear analysis could not differentiate culprit CFEs from bystanders. This study suggested that sites with a high level of fibrillation electrogram similarity at the CFE sites were important for AF maintenance. (J Cardiovasc Electrophysiol, Vol. 24, pp. 280-289, March 2013)
    No preview · Article · Nov 2012 · Journal of Cardiovascular Electrophysiology
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    ABSTRACT: Introduction: Data regarding the long-term outcome of catheter ablation in patients with nonpulmonary vein (NPV) ectopy initiating atrial fibrillation (AF) are limited. We aimed to evaluate the long-term result of patients with AF who had NPV triggers and underwent catheter ablation. Methods and results: The study included 660 consecutive patients (age 54 ± 11 years old, 477 males) who had undergone catheter ablation for AF. Group 1 consisted of 132 patients with AF initiating from the NPV, and group 2 consisted of 528 patients with AF initiating from pulmonary vein (PV) triggers only. Patients from Group 1 were younger than those from Group 2 (51 ± 12 years old vs 54 ± 11 years old, P = 0.001) and were more likely to be females (34.4% vs 25.8%, P = 0.049). The incidences of nonparoxysmal AF (36.4% vs 16.3%, P < 0.001) and right atrial (RA) enlargement (31.3% vs 19%, P = 0.004) were higher, and the biatrial substrates were worse in Group 1 than those in Group 2 (left atrial voltage 1.5 ± 0.7 mV vs 1.9 ± 0.7 mV, P < 0.001, RA voltage 1.6 ± 0.5 mV vs 1.8 ± 0.6 mV, P = 0.014). During a follow-up period of 46 ± 23 months, there was a higher AF recurrence rate in Group 1 than in Group 2 (57.6% vs 38.8%, P < 0.001). The independent predictors of AF recurrence were NPV trigger (P < 0.001, HR 2, 95% CI 1.4-2.85), nonparoxysmal AF (P = 0.021, HR 1.55, 95% CI 1.07-2.24), larger left atrial diameter (P = 0.002, HR 1.04, 95% CI 1.02-1.07) and worse left atrial substrate (P = 0.028, HR 1.3, 95% CI 1.03-1.64). Conclusion: Compared to AF originating from the PV alone, AF originating from the NPV ectopy showed a worse outcome.
    No preview · Article · Oct 2012 · Journal of Cardiovascular Electrophysiology
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    ABSTRACT: Background: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. The goal of the present study was to investigate whether exposure to non-steroidal anti-inflammatory drugs (NSAIDs) was a risk factor for AF, and to discern which patients were at the highest risk for AF due to NSAID use. Methods: A total of 7280 patients with newly diagnosed AF from 2000 to 2009 were identified from the National Health Insurance Research Database. On the same date of enrollment, 10 patients without AF, who were matched for age, sex, and underlying disease for each study patient, were selected to be the control group. The relationship between NSAID exposure before enrollment and AF risk was analyzed. Results: The NSAID use was associated with an increased AF risk, especially for new users (odds ratio [OR]=1.651). Among new users, subgroup analysis revealed that patients with heart failure were at the highest risk for AF (OR=1.920). For patients who were only exposed to selective cyclooxygenase 2 (COX2) inhibitors, no significant associations were found between AF and selective COX2 inhibitor use, except for patients with chronic kidney or pulmonary disease (OR=1.656 and 1.707, respectively). Conclusions: New NSAID use may predispose patients to AF, and the risk is almost doubled in heart failure patients. Use of selective COX2 inhibitors was not significantly related to AF occurrence, except in patients with chronic kidney or pulmonary disease.
    No preview · Article · Oct 2012 · International journal of cardiology

  • No preview · Article · Sep 2012 · International journal of cardiology
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    ABSTRACT: BACKGROUND: Atrial fibrosis plays a role in the development of a vulnerable substrate for atrial fibrillation (AF). Transforming growth factor (TGF)-ß1 is related to the degree of atrial fibrosis and the recurrence of AF after surgical maze procedures. Whether TGF-ß1 is associated with the outcome after catheter ablation for AF remains unclear. OBJECTIVE: We aimed to investigate whether plasma TGF-ß1 was an independent predictor of AF recurrence after catheter ablation. METHODS: Two hundred consecutive AF patients (154 with paroxysmal AF, and 46 with non-paroxysmal AF) underwent catheter ablation. Their TGF-ß1 levels, clinical and echocardiographic data were collected before ablation. RESULTS: Thirty patients (65%) with non-paroxysmal AF and 57 (37%) with paroxysmal AF had AF recur after catheter ablation. Among patients with non-paroxysmal AF, those experiencing recurrence had higher TGF-ß1 levels than those who did not experience recurrence (34.63±11.98ng/ml vs. 27.33±9.81ng/ml, p=0.026). In patients with paroxysmal AF, recurrence was not associated with different TGF-ß1 levels. In patients with non-paroxysmal AF, TGF-ß1 levels and left atrial diameter (LAD) were independent predictors of AF recurrence after catheter ablation. Moreover, TGF-ß1 levels had an incremental value over LAD to predict AF recurrence after catheter ablation (global χ2 of LAD alone: 6.3; LAD and TGF-ß1 levels: 11.9, increment in global χ2=5.6, p=0.013). The patients with small LAD and low TGF-ß1 levels had the lowest AF recurrence rate at 11%. CONCLUSION: TGF-ß1 level is an independent predictor of AF recurrence in patients with non-paroxysmal AF and might be useful for identifying the patients likely to have better outcomes after catheter ablation.
    No preview · Article · Sep 2012 · Heart rhythm: the official journal of the Heart Rhythm Society
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    ABSTRACT: Atrial fibrillation (AF) is an independent risk factor for stroke. Recent studies have demonstrated that the CHA(2)DS(2)-VASc scheme is useful for selecting patients who are truly at low risk. The goal of the present study was to compare the risk of ischemic stroke among AF patients with a CHA(2)DS(2)-VASc score of 0 (male) or 1 (female) with those without AF. The study enrolled 509 males (CHA(2)DS(2)-VASc score=0) and 320 females (CHA(2)DS(2)-VASc score=1) with AF who did not receive any antithrombotic therapy. Patients were selected from the National Health Insurance Research Database in Taiwan. For each study patient, 10 age-matched and sex-matched subjects without AF and without any comorbidity from the CHA(2)DS(2)-VASc scheme were selected as controls. The clinical end point was the occurrence of ischemic stroke. During a follow-up of 57.4±35.7 months, 128 patients (1.4%) experienced ischemic stroke. The event rate did not differ between groups with and without AF for male patients (1.6% vs 1.6%; P=0.920). In contrast, AF was a significant risk factor for ischemic stroke among females (hazard ratio, 7.77), with event rates of 4.4% and 0.7% for female patients with and without AF (P<0.001). AF males with a CHA(2)DS(2)-VASc score of 0 were at true low risk for stroke, which was similar to that of non-AF patients. However, AF females with a score of 1 were still at higher risk for ischemic events than non-AF patients.
    Preview · Article · Aug 2012 · Stroke
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    ABSTRACT: Background: The characteristics of atrial electrograms associated with atrial fibrillation (AF) termination are controversial. We investigated the electrogram characteristics that indicate procedural AF termination during continuous complex fractionated electrogram ablation. Methods and results: Fifty-two consecutive patients with persistent AF (47 men; aged 54 ± 9 years), who underwent electrogram-based catheter ablation in the left atrium and coronary sinus after pulmonary vein isolation, were enrolled. The intracardiac bipolar atrial electrogram recordings were characterized by (1) fractionation interval (FI) analysis (>6 seconds), (2) kurtosis (shape of the FI histogram), and (3) skewness (asymmetry of the FI histogram). Sites showing complex, fractionated electrograms (mean FI ≤ 60 ms) were targeted, and AF was terminated in 20 patients (38%) after the pulmonary vein isolation. The conventional complex fractionated electrogram sites (mean ≤ 120 ms) in patients with AF termination exhibited higher median kurtosis (2.69 [interquartile range, 2.03-3.46] versus 2.35 [interquartile range, 1.79-2.48]; P=0.024) and higher complex fractionated electrogram-mean interval (102.7 ± 19.8 versus 87.7 ± 15.0; P=0.008) than patients without AF termination. Furthermore, AF termination sites had higher median kurtosis than targeted sites without AF termination (5.13 [interquartile range, 3.51-6.47] versus 4.18 [interquartile range, 2.91-5.34]; P<0.01) in patients with procedural termination. In addition, patients with AF termination had a higher sinus rhythm maintenance rate after a single procedure than patients without AF termination (log-rank test, P=0.007). Conclusions: A kurtosis analysis using the FI histogram may be a useful tool in identifying the critical substrate for persistent AF and potential responders to catheter ablation.
    Full-text · Article · Jul 2012 · Circulation Arrhythmia and Electrophysiology
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    ABSTRACT: The different settings of the automatic algorithm in the Carto system (Carto XP, Biosense Webster, Diamond Bar, CA, USA) used for detecting complex fractionated electrograms (CFEs) during atrial fibrillation (AF) may influence the identification of the fragmented electrograms. We aimed to evaluate the impact of the different parameters on the detection of CFEs and the efficacy of the substrate modification after pulmonary vein isolation (PVI). A total of 1,159 electrograms were analyzed from 11 consecutive patients (age = 56 ± 12 years). The effect of the different algorithm factors, such as the high-voltage thresholds (0.12, 0.25, 0.5, 20 mV), detection algorithms (average complex interval [ACI] vs interval confidence level), and recording duration (2.5 seconds vs 5 seconds), on the disparities of the CFEs was investigated. The proportion of the different grades of CFEs depended on the detection algorithm and recording duration. The high-voltage threshold would not affect the consistency of the CFEs irrespective of the different settings of the detection algorithm or recording duration. High-grade CFEs were most consistent with an ACI algorithm and recording duration of 5 seconds (Cronbach's alpha = 0.952). Ablation consisting of a PVI and high-grade CFE sites converted AF directly to sinus rhythm in eight of 11 patients or into atrial tachycardia in one of 11. The distribution and consistency of the CFE detection depended on the detection algorithm and recording duration, but not on the high-voltage threshold. Under the ACI algorithm and a recording duration of 5 seconds, high-grade CFE sites remained highest consistency.
    No preview · Article · Jul 2012 · Pacing and Clinical Electrophysiology
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    ABSTRACT: AIMS: It remains unclear as to whether regional atrial substrates of certain areas of the atrium in patients with atrial fibrillation (AF) can be related to sinoatrial node dysfunction. We investigated the relationship between the biatrial substrate characteristics and sinus node function in these patients.METHODS AND RESULTS: The study enrolled 34 patients (aged 57 ± 11 years old; 20 males) who underwent catheter ablation for symptomatic paroxysmal AF. Sinus node dysfunction was defined as having corrected sinus node recovery time longer than 550 ms. Atrial substrate analyses of both atria and atrial conductive properties were investigated in patients with (Group 1) and without sinus node dysfunction (Group 2). The mean global bipolar voltage of both atria and the atrial refractory period were similar between the two groups. Regional analysis showed that the mean bipolar voltage for patients in Group 1 was lower than in Group 2 (1.0 ± 0.3 vs. 2.1 ± 0.7 mV, P < 0.001) only in the sinus node region, while the electrophysiological properties were similar for both groups in other anatomic regions of both atria. The right atrial total activation time was significantly longer (97 ± 9 vs. 89 ± 10 ms, P = 0.023) and the conduction velocity along the crista terminalis was significantly slower (1.0 ± 0.2 vs. 1.2 ± 0.3 m/s, P = 0.019) in Group 1 patients than in Group 2 patients.CONCLUSION: In patients with AF, regional atrial remodelling near the sinus node area was associated with sinus node dysfunction.
    No preview · Article · Jul 2012 · Europace
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    ABSTRACT: BACKGROUND: Renal dysfunction is recognized as an important risk factor for thromboembolic (TE) events in patients with atrial fibrillation (AF) under medical treatment. OBJECTIVE: To investigate whether renal dysfunction is a useful predictor of TE events among patients receiving AF ablation. We also aimed to determine whether the diagnostic accuracy of the CHA(2)DS(2)-VASc score in predicting TE events could be improved by adding renal dysfunction into the scoring system. METHODS: We enrolled a total of 547 patients with AF who underwent catheter ablation. Renal dysfunction was defined as an estimated glomerular filtration rate of <60 mL/min/1.73 m(2). The clinical end point was the occurrence of TE events (ischemic stroke, transient ischemic attack, or other systemic embolisms) during follow-up after catheter ablation. RESULTS: During a follow-up of 38.9 ± 22.5 months, 16 patients (2.9%) experienced TE events. Both the CHA(2)DS(2)-VASc score and renal dysfunction were independent predictors of TE events in the multivariate analysis. Among patients with a CHA(2)DS(2)-VASc score of 0 or 1, renal dysfunction can further stratify them into 2 groups with different event rates (4.3% vs 0.3%; P = .046). A new scoring system derived by assigning 1 more point representing renal dysfunction to the CHA(2)DS(2)-VASc score could improve its predictive accuracy; the area under the receiver operating characteristic curve increased from 0.84 to 0.88 (P = .043). CONCLUSIONS: Renal dysfunction was a significant risk factor for TE events after catheter ablation of AF and may improve the diagnostic accuracy of the CHA(2)DS(2)-VASc score.
    No preview · Article · Jun 2012 · Heart rhythm: the official journal of the Heart Rhythm Society
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    ABSTRACT: We report a case with dextrocardia, corrected transposition of the great arteries. He also had an atrial septum defect (ASD) with patch repair. Activation map showed a centrifugal activation from a focal origin on the systemic lower left atrial ASD patch. Ablation of the origin can terminate the atrial tachycardia. (PACE 2012; 35:e306-e308).
    No preview · Article · Jun 2012 · Pacing and Clinical Electrophysiology
  • Ambrose Kibos · Shih-Lin Chang · Pi-Chang Lee · Shih-Ann Chen

    No preview · Article · Jun 2012 · Circulation Journal
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    ABSTRACT: IntroductionLone atrial fibrillation (AF) is defined as AF occurring in the absence of any other cardiovascular disease. The prognosis of patients with lone AF varies in previous studies, and the clinical and electroanatomical characteristics of lone AF are unclear. The purpose of this study was to investigate the clinical characteristics of lone AF.Methods This study included 203 patients (52±13 years old, 144 males) that underwent circumferential pulmonary vein isolation (CPVI) for paroxysmal AF. The mean voltage and total activation time of the individual atria were obtained by using a NavX mapping system and were compared for patients with lone and non-lone AF. Several parameters, including the age, gender, AF duration, and left atrial (LA) diameter were analyzed.ResultsCompared with non-lone AF patients, lone AF patients were significantly younger (49±13 years old vs. 58±11 years old, p<0.001) and had lower body-mass index (BMI, 24.60±2.96 vs. 26.07±3.29, p=0.02), lesser cholesterol level (169.06±31.41 vs. 183.63±31.12, p=0.014), smaller LA diameter (35.89±4.90 vs. 40.86±4.62, p<0.001), and higher LA bipolar voltage (2.10±0.50 vs. 1.83±0.73 mV, p<0.05). Furthermore, a dramatic voltage reduction was observed for 60-year-old patients.Conclusion Patients with lone AF have unique clinical and electroanatomical characteristics.
    Preview · Article · Jun 2012 · Journal of Arrhythmia
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    ABSTRACT: BACKGROUND: Obesity is an important risk factor for atrial fibrillation (AF) and heart failure (HF). The effects of epicardial fat on atrial electrophysiology were not clear. This study was to evaluate whether HF may modulate the effects of epicardial fat on atrial electrophysiology. METHODS: Conventional microelectrodes recording was used to record the action potential in left (LA) and right (RA) atria of healthy (control) rabbits before and after application of epicardial fat from control or HF (ventricular pacing of 360-400bpm for 4weeks) rabbits. Adipokine profiles were checked in epicardial fat of control and HF rabbits. RESULTS: The LA 90% of AP duration was prolonged by control epicardial fat (from 77±6 to 87±7ms, p<0.05, n=7), and by HF epicardial fat (from 78±3 to 98±4ms, p<0.001, n=9). However, control or HF epicardial fat did not change the AP morphology in RA. HF epicardial fat increased the contractility in LA (61±11 vs. 35±6mg, p=0.001), but not in RA. Control fat did not change the LA or RA contractility. Moreover, control and HF epicardial fat induced early and delayed afterdepolarizations in LA and RA, but only HF epicardial fat provoked spontaneous activity and burst firing in LA (n=3/9, 33.3% vs. n=0/7, 0%, n=0/9, 0%, p<0.05). Compared to control fat, HF epicardial fat, had lower resistin, C-reactive protein and serum amyloid A, but similar interluekin-6, leptin, monocyte chemotactic protein-1, adiponectin and adipsin. CONCLUSIONS: HF epicardial fat increases atrial arrhythmogenesis, which may contribute to the higher atrial arrhythmia in obesity.
    No preview · Article · May 2012 · International journal of cardiology

Publication Stats

2k Citations
751.54 Total Impact Points


  • 2005-2016
    • Taipei Veterans General Hospital
      • • Cardiology Division
      • • Department of Medicine
      T’ai-pei, Taipei, Taiwan
    • National Yang Ming University
      • • Institute of Clinical Medicine
      • • School of Medicine
      T’ai-pei, Taipei, Taiwan
  • 2009
    • Chung Shan Medical University
      • Institute of Medicine
      臺中市, Taiwan, Taiwan
    • University of the Ryukyus
      • Faculty of Medicine
      Okinawa, Okinawa, Japan