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1.
Nanomedicine ; 46: 102601, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36089233

RESUMO

In this work, we conducted a proof-of-concept experiment based on biofunctionalized magneto-plasmonic nanoparticles (MPNs) and magneto-optical Faraday effect for in vitro Alzheimer's disease (AD) assay. The biofunctionalized γ-Fe2O3@Au MPNs of which the surfaces are modified with the antibody of Tau protein (anti-τ). As anti-τ reacts with Tau protein, biofunctionalized MPNs aggregate to form magnetic clusters which will hence induce the change of the reagent's Faraday rotation angle. The result showed that the γ-Fe2O3@Au core-shell MPNs can enhance the Faraday rotation with respect to the raw γ-Fe2O3 nanoparticles. Because of their magneto-optical enhancement effect, biofunctionalized γ-Fe2O3@Au MPNs effectively improve the detection sensitivity. The detection limit of Tau protein as low as 9 pg/mL (9 ppt) was achieved. Furthermore, the measurements of the clinical samples from AD patients agreed with the CDR evaluated by the neurologist. The results suggest that our method has the potential for disease assay applications.


Assuntos
Doença de Alzheimer , Nanopartículas , Humanos , Doença de Alzheimer/diagnóstico , Compostos Férricos , Ouro , Imunoensaio , Proteínas tau , Nanopartículas Metálicas
2.
J Formos Med Assoc ; 121(8): 1506-1514, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34782197

RESUMO

BACKGROUND/PURPOSE: Previous studies have seldom investigated the psychological factors that are associated with dissatisfaction with healthcare services. We therefore examined the associations of depression and anxiety with service dissatisfaction among older adults. METHODS: A community-based health survey was conducted from 2012 to 2016. Residents aged ≥65 years were randomly recruited from Yilan City, Taiwan. Besides overall dissatisfaction, we assessed dissatisfaction with physicians' ability, physicians' attitude, and waiting time. The Hospital Anxiety and Depression Scale was used to detect depressive and anxiety symptoms with optimal cut-off points of 3 for the anxiety subscale and 6 for the depression subscales. RESULTS: Of the 3480 residents included in this study, the overall dissatisfaction rate was 7.9%. After controlling for covariates, depressive and anxiety symptoms were consistently correlated with the various dimensions of dissatisfaction. More specifically, depressive symptoms were associated with overall dissatisfaction and dissatisfaction with physicians' ability and attitude. Conversely, anxiety was uniquely associated with dissatisfaction with waiting time. CONCLUSION: Psychological symptoms were consistent correlates of dissatisfaction with healthcare services among older adults, although the specific symptoms had different associations with the various dimensions of dissatisfaction.


Assuntos
Ansiedade , Depressão , Idoso , Ansiedade/epidemiologia , Transtornos de Ansiedade , Atenção à Saúde , Depressão/diagnóstico , Depressão/epidemiologia , Humanos , Taiwan
3.
Pacing Clin Electrophysiol ; 42(6): 637-645, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30900751

RESUMO

BACKGROUND: Premature ventricular contractions (PVCs) induced by subtle cardiac dysfunction are missed by echocardiography. We evaluated acoustic cardiography for detection of early electromechanical dysfunction in patients with idiopathic PVCs and normal left ventricular ejection fraction (LVEF), and investigated the impact of radiofrequency ablation (RFA) in reversing this adverse effect. METHODS: Eighty-six patients with PVCs and 33 normal controls having normal LVEF were studied. Fifty PVC patients were in the ablation group and 36 in the nonablation group. %Electromechanical activation time (%EMAT), %left ventricular systolic time (%LVST), third (S3) and fourth heart sound (S4), and systolic dysfunction index (SDI) during sinus rhythm (SR) were measured by acoustic cardiography (Audicor, Inovise Medical, Inc., Beaverton, OR, USA) pre- and postablation. In 28 patients, acoustic parameters were compared during SR without PVCs, and SR with single PVC, ≥ 2 PVCs, or ventricular tachycardia over 10-second Audicor recording in a single patient at different times. Twenty-four-hour acoustic cardiographic and acoustic cardiographic Holter recording were used to assess the impact of PVC burden on electromechanical function in 41 patients. RESULTS: %EMAT, S3, S4, and SDI showed significant worsening in the PVC versus control group. %EMAT and SDI were worsened with increasing PVC number in a 10-second strip. %EMAT showed significant linear increment with increasing PVC burden. There was a significant improvement in %EMAT, %LVST, S3, S4, and SDI postablation in patients with PVCs. CONCLUSION: Acoustic cardiography can detect PVC-induced minor electromechanical dysfunction in patients with normal LVEF. RFA can reverse this adverse effect.


Assuntos
Complexos Ventriculares Prematuros/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ablação por Cateter , Diagnóstico Precoce , Eletrocardiografia Ambulatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complexos Ventriculares Prematuros/cirurgia
4.
BMC Geriatr ; 18(1): 90, 2018 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-29653515

RESUMO

BACKGROUND: Fall episodes are not unusual among community residents, especially the elderly, and lower muscle strength is an important issue to address in order to prevent falls. METHODS: A community health survey was conducted in a suburban area of Taiwan, and 1067 older adults were selected for enrollment in the present study. All the enrolled subjects had been visited at their homes; the subjects' strength of both hands and muscle mass of both legs were measured and well-established questionnaires were finished by certificated paramedic staffs. RESULTS: The incidence of fall episodes in the previous 1 year in the Yilan elderly population was 15.1%, and the female predominance was significant. A significantly higher prevalence of cataracts was found in group who experienced a fall in the past year (64% vs. 54.9% in the non-fall group). Mild or more severe dementia was much more prevalent in the group who experienced a recent fall (33.8% vs. 25.7% in the non-fall group). The strength of both hands tested as the physical function was 17.6 ± 8.0 kg in the recent fall group, significantly weaker than that in the non-fall group (20.7 ± 8.7 kg). Multivariate regression analysis revealed a greater weekly exercise duration and greater strength of both hands reduced the occurrence of falls among the whole and the female population. The standardized effect sizes of hand grip strength between both groups, not trivial, were 0.29 and 0.37 for the total population and the female subpopulation respectively. CONCLUSIONS: Less weekly exercise duration and weaker muscle strength were f ound to be independent risk factors of fall episode(s) in an elderly Taiwanese population, especially in the female sub-population. Muscle strength, measured by average of both hands grip strength, was the most significantly factor of one-year fall episode(s) accessed retrospectively.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Exercício Físico/fisiologia , Inquéritos Epidemiológicos , Força Muscular/fisiologia , Acidentes por Quedas/prevenção & controle , Idoso , Feminino , Humanos , Incidência , Masculino , Prevalência , Estudos Retrospectivos , Fatores de Risco , Taiwan/epidemiologia
5.
Acta Cardiol Sin ; 34(3): 211-223, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29844642

RESUMO

BACKGROUND: Patients with acute coronary syndrome (ACS) and diabetes mellitus (DM) receive less aggressive treatment and have worse outcomes in Taiwan. We sought to explore whether the current practices of prescribing guideline-directed medical therapy (GDMT) for ACS and clinical outcomes have improved over time. METHODS: A total of 1534 consecutive diabetic patients with ACS were enrolled between 2013 and 2015 from 27 hospitals in the nationwide registry initiated by the Taiwan Society of Cardiology (the TSOC ACS-DM Registry). Baseline and clinical demographics, treatment, and clinical outcomes were compared to those of 1000 ACS patients with DM recruited in the Taiwan ACS-full spectrum (ACS-FS) Registry, which was performed between 2008 and 2010. RESULTS: Compared to the DM patients in the Taiwan ACS-FS Registry, even though reperfusion therapy was carried out in significantly fewer patients, the primary percutaneous coronary intervention (PCI) rate for ST-segment elevation myocardial infarction (STEMI) and the prescription rates of GDMT for ACS including P2Y12 inhibitors, renin-angiotensin blockers, beta-blockers, and statins were significantly higher in those in the TSOC ACS-DM Registry. Moreover, significant reductions in 1-year mortality, recurrent nonfatal MI and stroke were observed compared to those of the DM patients in the Taiwan ACS-FS Registry. Multivariate analysis identified reperfusion therapy in combination with GDMT as a strong predictor of better 1-year outcomes [hazard ratio (95% confidence interval) = 0.54 (0.33-0.89)]. CONCLUSIONS: Marked improvements in performing primary PCI for STEMI and prescribing GDMT for ACS were observed over time in Taiwan. This was associated with improved 1-year event-free survival in the diabetic patients with ACS.

7.
Acta Cardiol Sin ; 33(1): 50-57, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28115807

RESUMO

BACKGROUND: It is critical to recognize high risk patients who are prone to develop stroke in the management of atrial fibrillation (AF). The purpose of this study was to identify the determinants of AF related stroke by assessing the anatomical and functional remodeling of cardiac chambers. METHODS: We compared the cardiac structure and function of 28 consecutive patients with paroxysmal and persistent AF-related stroke with 69 patients with AF and 21 controls without stroke using contrast-enhanced 64-slice multi-detector computed tomography during sinus rhythm. RESULTS: The volume of left atrium (LA), LA appendage (LAA) and right atrium (RA) were significantly increased across the groups with sinus rhythm (SR), AF and AF-related stroke (p < 0.001 for each, respectively). The emptying fraction and booster-pump function of LA, LAA and RA were decreased across the groups (p < 0.001 for each). In addition, the left ventricular mass index was increased in AF related stroke (p = 0.003). Using multivariate analysis, increased age (p = 0.003), reduced booster-pump function of LA (p = 0.01), LAA (p < 0.001) and RA (p < 0.001) were shown to be independently associated with the occurrence of stroke. CONCLUSIONS: The dilatation and contractile dysfunction of both atria are related to the development of stroke in patients with paroxysmal and persistent AF. Our results suggested that the use of substrate-based assessment may help improve risk stratification of stroke in patients with AF.

8.
Tohoku J Exp Med ; 238(1): 75-83, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-26725845

RESUMO

Atrial fibrillation (AF) is currently recognized as one of the most common cardiac arrhythmias worldwide, with the increasing prevalence that has been estimated to be as high as 9% among the elderly. Health-related quality of life (HRQoL) has become an important patient-centered health outcome measurement, but the impacts created by AF and other arrhythmias with similar symptoms, such as frequent atrial and ventricular premature contractions (APCs and VPCs, defined as ≥ 3 beats/5 minutes), have not been extensively evaluated. The Yilan Study is a population-based community health survey, which in part aims to evaluate the prevalence and impacts of these arrhythmias on the HRQoL in a community dwelling elderly population. A total of 1,732 citizens from the Yilan, Taiwan, aged 65 years or older (45.8% male) were enrolled and visited at their homes, where HRQoL was measured utilizing the Short Form-12 Health Survey. Each participant's heart rhythm was recorded with an electrocardiographic monitor for 5 minutes. The results disclosed that the prevalence of AF of this aged population was 5.8%, similar to the mean global prevalence. Besides, the prevalence of frequent APCs and frequent VPCs in these elderly people were 7.1% and 5.5%, respectively. After multiple regression analysis, elderly people with AF had lower scores in the physical component of HRQoL, while those elderly people with frequent VPCs had lower scores in the mental component. Ultimately, these findings can provide additional useful and population-specific information about AF, and assist medical professionals in designing more effective strategies for cardiac arrhythmia treatments.


Assuntos
Fibrilação Atrial/complicações , Complexos Cardíacos Prematuros/complicações , Qualidade de Vida , Idoso , Fibrilação Atrial/epidemiologia , Demografia , Feminino , Humanos , Masculino , Prevalência , Análise de Regressão , Taiwan/epidemiologia
9.
Acta Cardiol Sin ; 32(2): 174-84, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27122948

RESUMO

BACKGROUND: A recent study reported the close relationship between high dominant frequent (DF) sites [atrial fibrillation (AF) nest] and the intrinsic cardiac autonomic nervous system. The aim of this study was to investigate the correlation between the regional distribution of epicardial fat and the properties of the biatrial substrates in AF patients. METHODS: We studied 32 patients with paroxysmal (n = 23) and persistent (n = 9) AF. The epicardial fat volume around the left atrium (LA) was evaluated using 64-slice multidetector computed tomography and the topographic distribution of the fat volume was assessed. The biatrial DFs, voltages, and total activation times (TATs) were obtained during sinus rhythm. RESULTS: Out of the 8 divided LA regions, a significant linear correlation existed between the LA fat and mean DF values in the right upper anterior LA, left upper anterior LA, right lower anterior LA, right upper posterior LA, left upper posterior LA, and left lower posterior LA. There was no significant correlation between the regional LA fat distribution and regional LA peak-to-peak bipolar voltage and TAT. During a mean follow-up of 17 ± 8 months, 22 of the 32 (69%) patients were free of AF. In the multivariate analysis, only the mean LA DF was found to be a significant predictor of recurrence. CONCLUSIONS: There was a close association between the regional distribution of the LA epicardial fat and the atrial substrate manifesting high frequency during sinus rhythm (AF nest). Those nests were related to ablation outcome. Hence, epicardial fat may play a significant role in atrial substrate remodeling and thereby in the pathogenesis and maintenance of AF. KEY WORDS: Atrial fibrillation • Dominant frequency • Epicardial fat • Nest • Recurrence.

10.
J Cardiovasc Electrophysiol ; 26(10): 1048-56, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26178628

RESUMO

BACKGROUND: The recurrence of atrial fibrillation (AF) is not uncommon in the era of catheter ablation. This study aimed to evaluate the characteristics of AF patients who underwent multiple (>2) ablation procedures. METHODS AND RESULTS: Of 666 consecutive patients (53 ± 11 y/o, 484 men) who underwent catheter ablation of AF (paroxysmal AF, n = 530), 144 (22%) underwent 2 procedures and 52 (8%) underwent more than 2 procedures due to symptomatic recurrences refractory to medication during 48 ± 23 months of follow-up. Baseline and procedural characteristics at the index procedure were investigated to determine their impact on the necessity of multiple procedures. After 2 procedures, 48 (92%) of 52 patients had pulmonary vein (PV) ectopic beats initiating AF. Coexisting PV and non-PV triggers were found in 23 of 48 patients. In a multivariate analysis, the presence of non-PV triggers (P = 0.004; odds ratio 2.69, 95% CI 1.37-5.28) at the index procedure was the only independent predictor of necessary multiple procedures. Among patients with non-PV ectopic beats initiating AF at the index procedure, the presence of ligament of Marshall triggers (P = 0.001, odds ratio 6.74, 95% CI 2.13-21.32) could predict the necessity of multiple procedures. CONCLUSIONS: The need for multiple catheter ablation procedures can be predicted by the presence of non-PV ectopic beats initiating AF at the index procedure. However, PV-initiated AF remains the major cause of AF recurrence despite multiple catheter ablation procedures.


Assuntos
Fibrilação Atrial/epidemiologia , Fibrilação Atrial/cirurgia , Complexos Atriais Prematuros/epidemiologia , Complexos Atriais Prematuros/cirurgia , Ablação por Cateter/estatística & dados numéricos , Reoperação/estatística & dados numéricos , Fibrilação Atrial/diagnóstico , Complexos Atriais Prematuros/diagnóstico , Comorbidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Veias Pulmonares/cirurgia , Recidiva , Medição de Risco , Taiwan/epidemiologia , Falha de Tratamento , Resultado do Tratamento
11.
Acta Cardiol Sin ; 31(4): 317-24, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27122888

RESUMO

BACKGROUND: Dissociated activity can occur after circumferential thoracic vein isolation for treating atrial fibrillation (AF). However, its clinical significance and response to adenosine remain unclear. METHODS: Fifty-three patients (10 women, 11 with non-paroxysmal AF, with mean age 54.4 ± 11.2 years) with slow dissociated activity after thoracic vein isolation for AF ablation were analyzed. Adenosine (12 mg) was injected intravenously into 30 patients, and the responses of the dissociated activities were recorded. RESULTS: The clinical characteristics and the rate of recurrence did not differ between patients with and without dissociated activity. Dissociated activity was most frequently observed at the right superior pulmonary vein (PV) (61%), left superior PV (26%), right inferior PV (5%), left inferior PV (4%), and non-PV sites (4%). The locations of dissociated activities were associated with the AF trigger sites (p = 0.004). Adenosine injection decreased the cycle length of dissociated activity in 13 patients (group 1) and increased it in 17 patients (group 2). Dissociated activity disappeared in 7 patients (41%) (group 2) after adenosine injection. During the mean 33 ± 17 months of follow-up, group 2 patients had a lower AF recurrence rate (24%) than group 1 patients (62%) (p = 0.035). CONCLUSIONS: The locations of dissociated activity were closely associated with the AF trigger sites. The responses to adenosine may predict AF recurrence in patients with dissociated activity. KEY WORDS: Ablation; Atrial fibrillation; Dissociated activity.

12.
J Cardiovasc Electrophysiol ; 25(8): 803-812, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24628987

RESUMO

INTRODUCTION: The optimal substrate ablation approach in patients with persistent atrial fibrillation (Per AF) remains unclear. This was a prospective randomized study comparing the efficacy of limited (continuous complex fractionated atrial electrogram, CFAE: <60 milliseconds) versus extensive (continuous CFAE plus variable CFAE: <120 milliseconds) atrial substrate modification in Per AF patients. METHODS AND RESULTS: We enrolled 120 Per AF patients in the study, and 30 patients with AF termination after pulmonary vein isolation (PVI) were excluded. In the remaining 90 patients, 45 were treated with limited approach (Group 1) and 45 with an extensive approach (Group 2). The end point of the study was the incidence of an atrial arrhythmia recurrence postblanking period. The patients were followed up for 15 months with 3-month clinical reviews, electrograms (ECGs), Holter recordings, and echocardiographic monitoring. Procedural AF termination and the single procedural efficacy were statistically comparable between the 2 groups (48.9% vs. 63.4% in Groups 1 and 2, respectively, P = 0.289). During the follow-up, patients who received limited ablation had a lower incidence of recurrent AFL (P = 0.04), and better reverse remodeling of the left atrium (LA, P = 0.04). After 2 procedures, the freedom from any atrial arrhythmia was better in Group 2 (62.2% vs. 87.8%, P = 0.009). Those with longstanding AF and a larger baseline LA size responded better to the extensive ablation. CONCLUSIONS: In the Per AF patients who failed to achieve AF termination after PVI alone, a specific atrial substrate modification approach targeting only continuous CFAEs could be considered as an initial ablation strategy.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Veias Pulmonares/cirurgia , Adulto , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Ablação por Cateter/efeitos adversos , Ecocardiografia Doppler , Ecocardiografia Transesofagiana , Eletrocardiografia Ambulatorial , Técnicas Eletrofisiológicas Cardíacas , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/fisiopatologia , Recidiva , Taiwan , Fatores de Tempo , Resultado do Tratamento
13.
Comput Methods Programs Biomed ; 252: 108236, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38776829

RESUMO

BACKGROUND AND OBJECTIVE: Strain analysis provides insights into myocardial function and cardiac condition evaluation. However, the anatomical characteristics of left atrium (LA) inherently limit LA strain analysis when using echocardiography. Cardiac computed tomography (CT) with its superior spatial resolution, has become critical for in-depth evaluation of LA function. Recent studies have explored the feasibility of CT-derived strain; however, they relied on manually selected regions of interest (ROIs) and mainly focused on left ventricle (LV). This study aimed to propose a first-of-its-kind fully automatic deep learning (DL)-based framework for three-dimensional (3D) LA strain extraction on cardiac CT. METHODS: A total of 111 patients undergoing ECG-gated contrast-enhanced CT for evaluating subclinical atrial fibrillation (AF) were enrolled in this study. We developed a 3D strain extraction framework on cardiac CT images, containing a 2.5D GN-U-Net network for LA segmentation, axis-oriented 3D view extraction, and LA strain measure. The segmentation accuracy was evaluated using Dice similarity coefficient (DSC). The model-extracted LA volumes and emptying fraction (EF) were compared with ground-truth measurements using intraclass correlation coefficient (ICC), correlation coefficient (r), and Bland-Altman plot (B-A). The automatically extracted LA strains were evaluated against the LA strains measured from 2D echocardiograms. We utilized this framework to gauge the effect of AF burden on LA strain, employing the atrial high rate episode (AHRE) burden as the measurement parameter. RESULTS: The GN-U-Net LA segmentation network achieved a DSC score of 0.9603 on the test set. The framework-extracted LA estimates demonstrated excellent ICCs of 0.949 (95 % CI: 0.93-0.97) for minimal LA volume, 0.904 (95 % CI: 0.86-0.93) for maximal LA volume, and 0.902 (95 % CI: 0.86-0.93) for EF, compared with expert measurements. The framework-extracted LA strains demonstrated moderate agreement with the LA strains based on 2D echocardiography (ICCs >0.703). Patients with AHRE > 6 min had significantly lower global strain and LAEF, as extracted by the framework than those with AHRE ≤ 6 min. CONCLUSION: The promising results highlighted the feasibility and clinical usefulness of automatically extracting 3D LA strain from CT images using a DL-based framework. This tool could provide a 3D-based alternative to echocardiography for assessing LA function.


Assuntos
Fibrilação Atrial , Átrios do Coração , Imageamento Tridimensional , Tomografia Computadorizada por Raios X , Humanos , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Tomografia Computadorizada por Raios X/métodos , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/fisiopatologia , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Aprendizado Profundo , Algoritmos , Ecocardiografia/métodos
14.
J Cardiovasc Electrophysiol ; 24(6): 609-16, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23437785

RESUMO

INTRODUCTION: Autonomic modulation of the cardiac activity plays an important role in the pathogenesis of atrial fibrillation (AF). The aim of this study was to assess the differences in the atrial electrical and structural properties between patients with vagal and sympathetic AF. METHODS: The study included 30 patients (53 ± 12 years old, male 26) with frequent attacks of symptomatic paroxysmal AF. All cases underwent 24-hour ambulatory Holter monitoring before the catheter ablation. The onset of AF accompanied with an increased HF component and decreased L/H ratio was designated as a vagal type (group 1, n = 12), whereas a decreased HF component and increased L/H ratio was classified as a sympathetic type (group 2, n = 18). Electrical and structural properties were evaluated during the ablation procedure. RESULTS: All patients had AF originating from PVs. There was a higher incidence of non-PV triggers in group 2 patients than that in group 1 (44% vs 8%, P = 0.04). Group 1 had a higher bipolar peak-to-peak voltage and mean DF of the global left atrium (LA), shorter total activation time, and smaller LA volume than group 2, whereas the electrical and structural properties in the right atrium were similar. After a follow-up of 15 ± 7 months, there was a lower incidence of AF recurrence in group 1 than that in group 2 (0% vs 28%, P = 0.02). CONCLUSION: There are better electrical properties and a smaller LA volume in patients with vagal-type AF. In contrast, the LA substrate is worse, and coexisting non-PV triggers and recurrence following ablation are more prevalent in patients with the sympathetic-type AF.


Assuntos
Fibrilação Atrial/fisiopatologia , Átrios do Coração/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Nervo Vago/fisiopatologia , Ablação por Cateter , Eletrocardiografia Ambulatorial , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
15.
J Cardiovasc Electrophysiol ; 24(4): 375-80, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23252831

RESUMO

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.


Assuntos
Fibrilação Atrial/cirurgia , Função Atrial , Isquemia Encefálica/etiologia , Ablação por Cateter/efeitos adversos , Acidente Vascular Cerebral/etiologia , Adulto , Idoso , Área Sob a Curva , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Isquemia Encefálica/fisiopatologia , Distribuição de Qui-Quadrado , Ecocardiografia Doppler de Pulso , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Curva ROC , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
16.
J Cardiovasc Electrophysiol ; 24(3): 280-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23130721

RESUMO

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.


Assuntos
Algoritmos , Fibrilação Atrial/diagnóstico , Técnicas Eletrofisiológicas Cardíacas , Sistema de Condução Cardíaco/fisiopatologia , Dinâmica não Linear , Processamento de Sinais Assistido por Computador , Adulto , Idoso , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Ablação por Cateter , Distribuição de Qui-Quadrado , Feminino , Sistema de Condução Cardíaco/cirurgia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , Fatores de Tempo , Resultado do Tratamento
17.
J Cardiovasc Electrophysiol ; 24(3): 250-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23210627

RESUMO

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.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter , Sistema de Condução Cardíaco/cirurgia , Adulto , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/fisiopatologia , Distribuição de Qui-Quadrado , Ecocardiografia Doppler , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Feminino , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Veias Pulmonares/fisiopatologia , Veias Pulmonares/cirurgia , Recidiva , Reoperação , Medição de Risco , Fatores de Risco , Taiwan/epidemiologia , Fatores de Tempo , Resultado do Tratamento
18.
Europace ; 15(5): 676-84, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23193161

RESUMO

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 CHA2DS2-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 CHA2DS2-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 CHA2DS2-VASc score.


Assuntos
Antiarrítmicos/uso terapêutico , Fibrilação Atrial/mortalidade , Fibrilação Atrial/terapia , Doenças Cardiovasculares/mortalidade , Ablação por Cateter/mortalidade , Sistema de Registros/estatística & dados numéricos , Acidente Vascular Cerebral/mortalidade , Estudos de Coortes , Terapia Combinada/mortalidade , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Medição de Risco , Acidente Vascular Cerebral/prevenção & controle , Análise de Sobrevida , Taxa de Sobrevida , Taiwan/epidemiologia , Resultado do Tratamento
19.
Circ J ; 77(8): 2014-23, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23698026

RESUMO

BACKGROUND: Dyspepsia is not uncommon in patients undergoing ablation of atrial fibrillation (AF). The purpose of this study was to investigate the change in gastric myoelectrical activity and its relationship to the outcome after ablation by electrogastrography (EGG). METHODS AND RESULTS: The study prospectively enrolled 32 patients: 16 patients (Group 1) had AF and 16 (Group 2) had paroxysmal supraventricular tachycardia. The myoelectricity-like signals of the gastrointestinal tract were recorded using EGG before, immediately, and 3 months after ablation. Both fasting and postprandial abnormal gastric wave percentages increased immediately after ablation in Group 1 when compared with before ablation. Increased fasting (12.8 ± 15.2% vs. 22.3 ± 21.0%, P=0.04) and postprandial (10.4 ± 6.2% vs. 21.2 ± 14.5%, P=0.01) bradygastria percentages were noted immediately after ablation in Group 1 when compared with before ablation. These findings were not observed in Group 2. The normal gastric wave percentage returned to baseline 3 months after procedure. In total, 4 (25%) patients in Group 1 had a recurrence of AF after a follow-up of 18 ± 3 months; those without recurrence had a significantly higher percentage of postprandial abnormal gastric waves immediately after ablation when compared with recurrence. CONCLUSIONS: Transient gastric dysrhythmias with bradygastria does occur in AF patients after ablation, which may indicate periesophageal vagal plexus damage after ablation. Careful application of radiofrequency energy to prevent esophageal injury is important.


Assuntos
Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Fenômenos Eletrofisiológicos , Hipocinesia/fisiopatologia , Músculo Liso/fisiopatologia , Estômago/fisiopatologia , Feminino , Seguimentos , Humanos , Hipocinesia/etiologia , Masculino , Estudos Prospectivos , Taquicardia Supraventricular/fisiopatologia , Taquicardia Supraventricular/cirurgia
20.
Int J Cardiol ; 371: 175-183, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36216093

RESUMO

AIMS: The underlying mechanisms of atrial remodeling in cardiac implanted electronic device(CIED)-detected atrial high-rate episodes(AHRE) remains to be elucidated. METHODS: A cardiac computed tomography and a strain echocardiography were performed to delineate the structural and functional characteristics of both atria. Biatrial volumes, emptying fraction(EF) and peak atrial longitudinal/contractile strain(PALS/PACS) were evaluated. All AHRE were analyzed. RESULTS: A total of 80 CIED patients with AHRE were categorized by AHRE duration into 3 groups: Group 1: <6 min(n = 42), Group 2: 6 min âˆ¼ 6 h(n = 23), and Group 3: >6 h(n = 15). Left atrial(LA) maximal volume(Vmax), atrial precontraction volume(Vapc), minimal volume(Vmin), LAEF, and PALS/PACS were all increasingly worsened among the patients in the 3 groups (p value for trend <0.05). Compared to Group 1, Group 2 had decreased LA PALS/PACS. There was no significant difference in LA volume or EF between Group 1 and 2. Group 3 had enlarged biatrial volumes (LAVmax: 57.1(SD 16.0) vs. 45.4(SD 9.2) mL/m2, p = 0.002; LAVmin: 42.6(SD 18.2) vs. 28.2(SD 7.2) mL/m2, p < 0.001), impaired total LAEF (28.0(SD 13.7) vs. 38.2(SD 7.7)%, p = 0.004) and reduced PALS/PACS compared to Group 1. Atrial remodeling in those with AHRE >6 h had increased LA volumes, impaired LAEF and reduced PALS/PACS compared to those with AHRE <6 h. CONCLUSION: Functional remodeling of the atria manifested after AHRE >6 min. Increased biatrial volumes and decreased LA reservoir and pump function occurred when AHRE were > 6 h. These LA structural and functional may be considered surrogate imaging markers for stroke risk assessment in patients with CHA2DS2-VASc ≥2 and AHRE.


Assuntos
Fibrilação Atrial , Remodelamento Atrial , Humanos , Fibrilação Atrial/diagnóstico por imagem , Átrios do Coração/diagnóstico por imagem , Medição de Risco , Ecocardiografia
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