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1.
Adv Exp Med Biol ; 1232: 331-337, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893428

RESUMO

Obesity, a risk factor of coronary artery disease, is known to cause peripheral microcirculatory disturbances. This study evaluated the relationship between the degree of obesity and peripheral microcirculatory disturbances, using peripheral near infrared spectroscopy (NIRS) with a vascular occlusion test (VOT). We compared correlations between the NIRS parameter changes induced by VOT and body mass index (BMI) in patients with and without statin therapy. A NIRS probe was set on the right thenar eminence, brachial artery blood flow was blocked for 3 min, and then released. Although total hemoglobin (ΔcHb), deoxyhemoglobin (ΔHHb) and tissue oxygenation index (ΔTOI) were not correlated with BMI, a significant negative correlation was found between oxyhemoglobin (ΔO2Hb) and BMI in the overall study population (r = -0.255, p-value 0.02). In addition, a significant negative correlation was found between ΔO2Hb and BMI in patients without statin therapy (r = -0.353, p-value 0.02) but not in patients with statin therapy (r = -0.181, p-value 0.27). These findings suggest that ΔO2Hb may be a useful indicator to assess peripheral microcirculation.


Assuntos
Índice de Massa Corporal , Doença da Artéria Coronariana , Espectroscopia de Luz Próxima ao Infravermelho , Idoso , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Microcirculação/fisiologia , Oxigênio , Consumo de Oxigênio , Oxiemoglobinas/metabolismo , Fatores de Risco , Espectroscopia de Luz Próxima ao Infravermelho/normas
2.
Adv Exp Med Biol ; 1232: 355-360, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893431

RESUMO

Epicardial adipose tissue (EAT) is associated with visceral fat and various cardiac disorders, such as atrial fibrillation and adverse cardiovascular events. Therefore, it is important to develop a simple and non-invasive inspection method to assess EAT, to prevent unfavorable cardiac events. This study assessed correlations between near-infrared spectroscopy (NIRS) changes induced by a vascular occlusion test (VOT) and EAT volume measured by cardiac computed tomography (CCT) in patients with suspected coronary artery disease. We also assessed correlations between body mass index (BMI) and EAT volume in the same population. In addition, these correlations were compared in patients treated with statin therapy and in those without statin therapy. A NIRS probe was set on the right thenar eminence, and brachial artery blood flow was blocked for 3 min before being released. A negative correlation was found between oxyhemoglobin (ΔO2Hb) and EAT volume in the overall study population (r = -0.236, p = 0.03). Interestingly, although a strong correlation was observed in patients without statin therapy (r = -0.488, p < 0.001), this correlation was not observed in patients with statin therapy (r = 0.157, p = 0.34). These findings suggest that NIRS measurements with VOT may be a useful method to identify patients with high EAT volume and high cardiovascular risks.


Assuntos
Doença da Artéria Coronariana , Espectroscopia de Luz Próxima ao Infravermelho , Tecido Adiposo/metabolismo , Idoso , Índice de Massa Corporal , Angiografia por Tomografia Computadorizada , Doença da Artéria Coronariana/diagnóstico , Feminino , Humanos , Masculino , Oxiemoglobinas/metabolismo , Fatores de Risco
3.
Circ Arrhythm Electrophysiol ; 12(10): e007281, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31610720

RESUMO

BACKGROUND: Ganglionated plexi (GPs) play an important role in both the initiation and maintenance of atrial fibrillation (AF). GPs can be located by using continuous high-frequency stimulation (HFS) to elicit a vagal response, but whether the vagal response phenomenon is common to patients without AF is unknown. METHODS: HFS of the left atrial GPs was performed in 42 patients (aged 58.0±10.2 years) undergoing ablation for AF and 21 patients (aged 53.2±12.8 years) undergoing ablation for a left-sided accessory pathway. The HFS (20 Hz, 25 mA, 10-ms pulse duration) was applied for 5 seconds at 3 sites within the presumed anatomic area of each of the 5 major left atrial GPs (for a total of 15 sites per patient). We defined vagal response to HFS as prolongation of the R-R interval by >50% in comparison to the mean pre-HFS R-R interval averaged over 10 beats and active-GP areas as areas in which a vagal response was elicited. RESULTS: Overall, more active-GP areas were found in the AF group patients than in the non-AF group patients, and at all 5 major GPs, the maximum R-R interval during HFS was significantly prolonged in the AF patients. After multivariate adjustment, association was established between the total number of vagal response sites and the presence of AF. Conclusions The significant increase in vagal responses elicited in patients with AF compared with responses in non-AF patients suggests that vagal responses to HFS reflect abnormally increased GP activity specific to AF substrates.

4.
Int Heart J ; 60(4): 812-821, 2019 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-31308323

RESUMO

Pulmonary vein isolation (PVI) of atrial fibrillation (AF) can reduce the AF burden and, potentially, reduce the long-term risk of strokes and death. However, it remains unclear whether anticoagulants can be stopped after PVI because of post-ablation AF recurrence in some patients. This study aimed to investigate the discontinuation rate of anticoagulants and long-term incidence of strokes after PVI.We enrolled 512 consecutive Japanese patients with AF (mean age, 63.4 ± 10.4 years; 123 women; 234 with non-paroxysmal AF; CHADS2 score/CHA2DS2-VASC score, 1.32 ± 1.12/2.21 ± 1.54) who underwent PVI between 2012 and 2015. During a 28.0 ± 17.1 -month follow-up, anticoagulants were terminated in 230 (44.9%) of the 512 patients, AF recurred in 200 (39.1%), and 10 (1.95%) suffered from a stroke. Death occurred in 5 (0.98%) patients. Although the incidence of strokes, by a Kaplan-Meier analysis, was similar, the incidence of death was lower (Hazard ratio 0.37, 95% confidence interval 0.12-0.93, P = 0.041) in the AF ablation group than the control group without ablation after 1:1 propensity score matching (the control data was derived from 2,986 patients in the SAKURA AF Registry, a large-cohort AF registry).Anticoagulants were discontinued in nearly half the patients who underwent AF ablation; of these, 39.1% experienced AF recurrences, 1.95% suffered from strokes, and 0.98% died, but the risk of death after AF ablation appeared to be lower than that in a propensity score-matched control group without ablation during long-term follow-up.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Eletrocardiografia , Complicações Pós-Operatórias/epidemiologia , Medição de Risco/métodos , Idoso , Fibrilação Atrial/fisiopatologia , Feminino , Seguimentos , Humanos , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Recidiva , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
5.
J Cardiovasc Electrophysiol ; 30(8): 1261-1269, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31111558

RESUMO

INTRODUCTION: Although electrophysiologic and anatomic factors associated with the need for touch-up radiofrequency (RF) applications after cryoballoon ablation (CBA) for atrial fibrillation (AF) have been well described, those associated with the need for such touch-up after hot balloon ablation (HBA) have not. We aimed to identify factors predictive of the need for touch-up applications following HBA. METHODS: Anatomic and electrophysiologic factors predictive of the need for touch-up RF ablation were compared between 46 propensity score-matched pairs of patients who underwent HBA or CBA for AF. RESULTS: Touch-up RF ablation was more frequently required after HBA than after CBA (57% vs 30%, respectively; P = .01), and mostly at the anterior aspect of the left superior pulmonary vein (LSPV) carina after HBA (35%) but at the inferior aspect of the right inferior PV (RIPV) after CBA (71%). Post HBA touch-up was associated with male gender, a CHA 2 DS 2 -VASc score ≤ 2, PV-left atrial bipolar voltage ≥ 1.35 mV, and PV trunk length ≥ 24.0 mm; post CBA touch-up associated with a history of heart failure. CONCLUSION: Following balloon ablation for AF, there may be a need for touch-up applications, especially at the LSPV ridge after HBA but at the RIPV after CBA. It may behoove operators to expect a need for touch-up following HBA when patients are male, have a CHA2 DS 2 -VASc score ≤ 2 points, when PV-LA bipolar voltage is ≥ 1.35 mV, or when the PV trunk is ≥ 24.0 mm or following CBA when there is a history of heart failure.

6.
J Arrhythm ; 34(5): 511-519, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30327696

RESUMO

Background: Limited data exist on indicators of durable pulmonary vein isolation (PVI) undergoing cryoballoon ablation (CBA) for atrial fibrillation (AF). We investigated whether balloon temperature and time to PVI can be used to predict early PV reconduction (EPVR), including residual PV conduction and adenosine triphosphate-induced dormant conduction and the relation between touch-up ablation of EPVR sites and mid-term recurrence of AF. Methods: We obtained procedural and outcome data from the records of 130 consecutive patients who underwent CBA and followed up for 13.4 months. Results: EPVR was identified in 86 (17%) PVs of 61 (47%) patients. Balloon temperatures during 30 seconds (-27 ± 5.7°C vs -31 ± 5.5°C), 60 seconds (-36 ± 5.6°C vs -41 ± 5.4°C), and at the nadir point (-41 ± 7.4°C vs -49 ± 7.0°C) were significantly higher, and the time to PVI was longer (90 ± 50 seconds vs 52 ± 29 seconds) in PVs with EPVR than in those without (P < 0.0001 for all). Among PVs without EPVR, the time to PVI was longer and balloon temperature was lower for the left superior pulmonary vein/ right inferior pulmonary vein (LSPV/RIPV) than for the right superior pulmonary vein/left inferior pulmonary vein (RSPV/LIPV) (time: 60 ± 25/73 ± 37 seconds vs 41 ± 31/45 ± 20 seconds, P < 0.0001) (temp: -39.2 ± 11.3/-39.4 ± 8.3°C vs -33.8 ± 10.6/-33.6 ± 6.8°C, P = 0.0023). AF recurrence rates were equivalent between patients with and without EPVR (13% [8/69] vs 15% [9/61], P = 0.845). Conclusions: Cryoballoon temperature and time to PVI appear to be useful in predicting durable PVI, that is, prevention of EPVR, but the balloon temperature and time required for PVI differ between PVs. Although EPVR does not predict AF recurrence, high success rates can be expected when touch-up ablation of EPVR sites is performed.

7.
J Cardiol ; 72(6): 488-493, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30318077

RESUMO

OBJECTIVE: Despite use of provocation testing to unmask dormant left atrium (LA)-PV conduction after index pulmonary vein isolation (PVI) for atrial fibrillation (AF), AF recurrence still occurs, with PV reconnection as the main cause. In an effort to answer the question whether freedom from AF recurrence can be achieved by ablation that targets sites of dormant conduction, we compared sites of dormant conduction against sites of PV reconnection identified at the time of repeat ablation for AF recurrence. MATERIALS AND METHODS: The study group comprised 46 patients (30 men/16 women, aged 58.7±10.3 years) with AF (paroxysmal: n=37, persistent: n=9) who underwent repeat ablation for AF recurrence 12.3 (7.4-29.7) months after the index ablation procedure. Ipsilateral PVs were divided into 8 segments each (736 total segments), and the relation between dormant conduction sites and PV reconnection sites was determined per segment. RESULTS: Dormant LA-PV conduction was unmasked and ablated in 22 (47.8%) of the 46 patients at sites within 43 (5.8%) of the 736 PV segments. Late PV reconnection was found within 122 (17%) of the 736 PV segments at the time of re-ablation for AF recurrence. Only 22 (18%) of these 122 PV segments corresponded to dormant conduction sites identified during the index procedure. CONCLUSION: Although additional ablation to eliminate dormant PV conduction unmasked during the index ablation procedure is performed, the majority of PVs that show reconduction at the time of treatment for clinical AF recurrence are PVs that have not shown dormant conduction.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Sistema de Condução Cardíaco/cirurgia , Veias Pulmonares/cirurgia , Reoperação/métodos , Idoso , Fibrilação Atrial/fisiopatologia , Feminino , Átrios do Coração/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento
8.
Int Heart J ; 59(3): 497-502, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29743409

RESUMO

Atrial electrical and structural remodeling is related to the perpetuation of atrial fibrillation (AF) subsequent to sinus node dysfunction. We investigated the relationship between AF recurrence after catheter ablation and sinus node dysfunction in long-standing persistent AF patients using the sinus node recovery time (SNRT) after defibrillation.Fifty-one consecutive patients who underwent a first ablation for long-standing persistent AF were enrolled. Intracardiac cardioversion was applied before ablation in the absence of any antiarrhythmic drugs, and the power required to defibrillate, number, and SNRT after defibrillation were measured. All patients underwent the same designed radiofrequency catheter ablation procedure.No patient required permanent pacemaker implantation due to sinus dysfunction after the ablation. During the follow-up period of 28.4 months (3.6-43.7), 35 out of 51 patients (69%) experienced an AF recurrence. The AF recurrence was significantly associated with an older age (60 ± 11 versus 52 ± 12 years in the non-recurrence group, P = 0.0196), longer SNRT after defibrillation (1722 [1410-2656] versus 1295 [676-1651] msec, P = 0.0125), and larger left atrial (LA) volume (59 ± 25 versus 41 ± 15 mL, P = 0.0119). There were no significant differences in the AF duration, AF cycle length, and right and total atrial conduction times between the 2 groups. A longer SNRT after defibrillation (adjusted HR 2.13, 95%CI 1.16-3.71, P = 0.0152) and larger LA volume (adjusted HR 1.03, 95%CI 1.01-1.04, P = 0.0054) were independent predictors of AF recurrence after ablation.Assessment of the SNRT after defibrillation may help to predict a successful ablation in patients with long-standing persistent AF.


Assuntos
Fibrilação Atrial/complicações , Ablação por Cateter/efeitos adversos , Síndrome do Nó Sinusal/complicações , Nó Sinoatrial/fisiopatologia , Adulto , Idoso , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Remodelamento Atrial/fisiologia , Ablação por Cateter/métodos , Cardioversão Elétrica/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
9.
Circ Arrhythm Electrophysiol ; 11(5): e005861, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29700055

RESUMO

BACKGROUND: Hot balloon ablation (HBA) and cryoballoon ablation (CBA) were developed to simplify ablation for atrial fibrillation. Because the lesion characteristics and efficacy of these balloon modalities have not been clarified, we compared lesion characteristics and outcomes of HBA and CBA. METHODS: Of 165 consecutive patients who underwent initial catheter ablation for atrial fibrillation, 74 propensity scorematched (37 HBA and 37 CBA) patients were included in our study. RESULTS: Patients' clinical characteristics, including age, sex, body mass index, atrial fibrillation subtype, CHA2DS2-VASc score, and left atrial dimension, were similar between the 2 groups. Touch-up radiofrequency ablation was required for residual/dormant pulmonary vein conduction in 52% of the patients with HBA versus 24% of the patients with CBA (P=0.02) and often in the anterior aspect of the left superior pulmonary vein after HBA (41%) versus the inferior aspect of the inferior pulmonary veins after CBA (22%). HBA lesions were smaller than CBA lesions (23.8±7.9 versus 33.5±14.5 cm2; P=0.0007). Similar results were observed when lesions in each pulmonary vein were compared between groups. Twentyfour hours after the procedure, serum levels of the cardiac biomarkers, including troponin-T, creatine kinase, and creatine kinase-MB, were higher in the HBA group than in the CBA group. Atrial fibrillation recurrence did not differ between the groups within 6 (3% versus 11%; P=0.36) or 12 months (16% versus 16%; P=1.00). CONCLUSIONS: Although HBA lesions appear to be smaller than CBA lesions, middle-term outcomes are not statistically different between these balloon modalities.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Criocirurgia/métodos , Temperatura Alta , Veias Pulmonares/cirurgia , Potenciais de Ação , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Cateteres Cardíacos , Ablação por Cateter/efeitos adversos , Ablação por Cateter/instrumentação , Criocirurgia/efeitos adversos , Criocirurgia/instrumentação , Feminino , Frequência Cardíaca , Temperatura Alta/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Veias Pulmonares/fisiopatologia , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
10.
J Atr Fibrillation ; 9(6): 1538, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29250289

RESUMO

Background: The mechanism explaining the efficacy of cryoballoon ablation (CBA) for atrial fibrillation has not been clarified. Methods and Results: We compared lesion characteristics between patients in whom pulmonary vein isolation (PVI) was performed by CBA (n=56) and those by contact force (CF)-based RF ablation (n=56). We evaluated the 3-dimensional PV morphology before and after cryoballoon inflation. After PVI, a 3D left atrial voltage map was created. Pacing (10 mA and 2 ms) was performed within the low voltage area from the ablation line, and electrically unexcitable ablated tissue was identified. ATP-provoked dormant conduction after PVI occurred in 9 of the 224 (4%) PVs in the CBA group and in 13 of the 224 (6%) PVs in the CF group (P=0.3935). The inflated balloon stretched the PV from the original PV ostial surface by 7.1±3.5 mm, but at sites with (vs, sites without) residual PV potential/dormant conduction, the extent of the PV distension was reduced (4.0±4.0 mm vs. 7.2±3.4 mm, P<0.0001). The unexcitable ablated tissue around the PVs was significantly wider in CB patients than in CF patients (16.7±5.1 mm vs. 5.3±2.3 mm, P<0.0001). Conclusions: Use of the cryoballoon significantly distends the PV. Without this extensive distention, PVI may not be successful. CBA seems to yield wide unexcitable ablation zones. These factors seem to explain the durability of CBA lesions.

11.
J Arrhythm ; 33(6): 608-612, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29255509

RESUMO

Background: The association between circulating adiponectin levels and atrial fibrillation (AF) is uncertain. We, therefore, investigated whether an increased serum adiponectin level is implicated in the long-term recurrence of AF after ablation therapy. Methods: Our study included 100 consecutive patients (88 men; median age, 57.9±10.9 years) who underwent catheter ablation for AF at our hospital between 2011 and 2013. The adiponectin and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were measured before ablation and compared between those in whom AF recurred and those in whom AF did not recur. Results: Elevation in adiponectin levels was significantly associated with female sex, non-paroxysmal AF, heart failure, higher NT-proBNP and matrix metallo-proteinase-2 levels, and lower body mass index. After a stepwise adjustment for any potential confounding variables, the adiponectin levels remained significantly associated with female sex (beta=0.2601, P=0.0041), non-paroxysmal AF (beta=0.2708, P=0.0080), and higher NT-proBNP levels (beta=0.2536, P= 0.0138). During the median follow-up period of 26.2 months, AF recurred in 48 of the 100 patients. Stepwise multivariate adjustment showed that an increased log-transformed NT-proBNP (Hazard ratio [HR], 2.18; 95% confidence interval [CI] 1.25-4.00; P=0.0055), longer duration of AF (HR, 1.87; 95%CI 1.01-3.76; P=0.0465), and decreased left ventricular ejection fraction (HR, 0.96; 95%CI 0.93-0.99; P=0.0391) were independent predictors of recurrent AF after catheter ablation, but adiponectin was not. Conclusions: Our data indicated that adiponectin was partially responsible for progression of AF, but the correlation between adiponectin levels and AF recurrence was not significant.

12.
J Arrhythm ; 33(5): 447-454, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29021848

RESUMO

BACKGROUND: The relationship between cardiac contrast-enhanced magnetic resonance imaging (CE-MRI)-derived scar characteristics and substrate for ventricular tachycardia (VT) in patients with structural heart disease (SHD) has not been fully investigated. METHODS: This study included 51 patients (mean age, 63.3±15.1 years) who underwent CE-MRI with SHD and VT induction testing before ablation. Late gadolinium-enhanced (LGE) regions on MRI slices were quantified by thresholding techniques. Signal intensities (SIs) 2-6 SDs above the mean SI of the remote left ventricular (LV) myocardium were considered as scar border zones, and SI>6 SDs, as scar zone, and the scar characteristics related to VT inducibility and successful ablation via endocardial approaches were evaluated. RESULTS: The proportion of the total CE-MRI-derived scar border zone in the inducible VT group was significantly greater than that in the non-inducible VT group (26.3±9.9% vs. 19.2±7.8%, respectively, P=0.0323). The LV endocardial scar zone to total LV myocardial scar zone ratio in patients whose ablation was successful was significantly greater than that in those whose ablation was unsuccessful (0.61±0.11 vs. 0.48±0.12, respectively, P=0.0042). Most successful ablation sites were located adjacent to CE-MRI-derived scar border zones. CONCLUSIONS: By CE-MRI, we were able to characterize not only the scar, but also its location and heterogeneity, and those features seemed to be related to VT inducibility and successful ablation from an endocardial site.

13.
J Arrhythm ; 33(5): 483-487, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29021854

RESUMO

BACKGROUND: The mechanisms underlying self-perpetuation of persistent atrial fibrillation (AF) are not well understood. To gain insight into these mechanisms, we conducted a study comparing left atrial (LA) electroanatomic maps obtained during sinus rhythm between patients with paroxysmal AF (PAF) and patients with persistent AF (PerAF). METHODS: The study included 23 men with PAF (age, 56.3±12.1 years) and 13 men with PerAF (age, 54.3±13.4 years). LA voltage mapping was performed during sinus rhythm. The clinical and electroanatomic characteristics of the two groups were evaluated and analyzed statistically. RESULTS: The bipolar voltages at the LA septum, roof, and posterior wall, right superior pulmonary vein (PV) and its antrum, right superior PV carina, and right inferior PV antrum were significantly lower in patients with PerAF than in those with PAF. The bipolar voltages in other parts of the LA did not differ statistically between the two groups. CONCLUSION: PAF and PerAF seem to be characterized by differences in the regional voltage in the LA and PVs. The LA structural remodeling of PerAF may initiate from the right PVs and their antra and LA septum, roof, and posterior wall.

14.
J Arrhythm ; 33(4): 269-274, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28765756

RESUMO

BACKGROUND: The relationship between atrial electrogram (EGM) characteristics in atrial fibrillation (AF) and those in sinus rhythm (SR) are generally unknown. The activation rate and direction may affect EGM characteristics. We examined characteristics of left atrial (LA) EGMs obtained during pacing from different sites. METHODS: The study included 10 patients undergoing pulmonary vein isolation for AF. Atrial EGMs were recorded from a 64-pole basket catheter placed in the LA, and bipolar EGM amplitudes from the distal electrode pair (1-2) and proximal electrode pair (6-7) from 8 splines were averaged. The high right atrium (HRA), proximal coronary sinus (CSp), and distal coronary sinus (CSd) were paced at 600 ms and 300 ms. RESULTS: When the LA voltage at SR was ≥1.5 mV, bipolar voltages of the HRA were greater than those of the CSp, which were greater than those of the CSd, regardless of the pacing cycle length. The shorter pacing cycle length resulted in a reduction of the LA EGM voltage at sites of SR voltage ≥1.5 mV, but no significant difference was seen at sites where the SR EGM amplitude was between >0.5 and <1.5 mV. No significant differences were seen in intra-basket conduction times between pacing cycle lengths of 600 ms and 300 ms at any pacing site. CONCLUSION: The rate and direction-dependent reduction of the amplitude of atrial EGMs may explain, in part, the voltage discordance during SR and AF.

15.
J Arrhythm ; 33(3): 185-191, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28607613

RESUMO

BACKGROUND: Ablation targeting complex fractionated atrial electrograms (CFAEs) or high dominant frequency (DF) sites is generally effective for persistent atrial fibrillation (AF). CFAEs and/or high DF sites may exist in low-voltage regions, which theoretically represent abnormal substrates. However, whether CFAEs or high DF sites reflect low voltage substrates during sinus rhythm (SR) is unknown. METHODS: Sixteen patients with AF (8 with paroxysmal AF; 8, persistent AF) underwent high-density mapping of the left atrium (LA) with a 3-dimensional electroanatomic mapping system before ablation. The LA was divided into 7 segments and the mean bipolar voltage recorded during AF and SR, CFAEs (cycle lengths of 50-120 ms), and DF sites were assessed in each segment with either a duo-decapolar ring catheter (n=10) or a 64-pole basket catheter (n=6). Low-voltage areas were defined as those of <0.5 mV during AF and <1.0 mV during SR. RESULTS: Regional mean voltage recorded from the basket catheter showed good correlation between AF and SR (r=0.60, p<0.01); however, the % low-voltage area in the LA recorded from the ring catheter showed weak correlation (r=0.34, p=0.05). Mean voltage was lower during AF than during SR (1.0 mV [IQR, 0.5-1.4] vs. 2.6 mV [IQR, 1.8-3.6], p<0.01). The regional and overall % low-voltage area of the LA was greater during AF than during SR (20% vs. 11%, p=0.05). CFAEs and high DF sites (>8 Hz) did not correlate with % low-voltage sites during SR; however, CFAEs sites were located in high-voltage regions during AF and high DF sites were located in low voltage regions during AF. CONCLUSIONS: CFAEs and high DF areas during AF do not reflect damaged atrial myocardium as shown by the SR voltage. However, CFAEs and high DF sites may demonstrate different electrophysiologic properties because of different voltage amplitude during AF.

16.
J Interv Card Electrophysiol ; 49(2): 137-145, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28432503

RESUMO

PURPOSE: Recurrence of atrial fibrillation (AF) after pulmonary vein isolation (PVI) is mainly due to PV reconnections. Patient-specific tissue characteristics that may contribute remain unidentified. This study aimed to assess the relationship between the bipolar electrogram voltage amplitudes recorded from the PV-left atrial (LA) junction and acute PV reconnection sites. METHODS: Three-dimensional LA voltage maps created before an extensive encircling PVI in 47 AF patients (31 men; mean age 62 ± 11 years) were examined for an association between the EGM voltage amplitude recorded from the PV-LA junction and acute post-PVI PV reconnections (spontaneous PV reconnections and/or ATP-provoked dormant PV conduction). RESULTS: Acute PV reconnections were observed in 17 patients (36%) and in 24 (3%) of the 748 PV segments (16 segments per patient) and were associated with relatively high bipolar voltage amplitudes (3.26 ± 0.85 vs. 1.79 ± 1.15 mV, p < 0.0001) and a relatively low mean force-time integral (FTI) (428 ± 56 vs. 473 ± 76 gs, p = 0.0039) as well as FTI/PV-LA bipolar voltage (137 [106, 166] vs. 295 [193, 498] gs/mV, p < 0.0001). An analysis of the receiver operating characteristic curves revealed a high prognostic performance of the LA bipolar voltage and FTI/PV-LA bipolar voltage for acute PV reconnections (areas under the curve: 0.86 and 0.89, respectively); the best cutoff values were >2.12 mV and ≤183 gs/mV, respectively. CONCLUSIONS: The PV-LA voltage on the PV-encircling ablation line and FTI/PV-LA voltage were related to the acute post-PVI PV reconnections. A more durable ablation strategy is warranted for high-voltage zones.


Assuntos
Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Veias Pulmonares/fisiopatologia , Veias Pulmonares/cirurgia , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ondas de Rádio , Recidiva , Fatores de Risco , Volume Sistólico
18.
Pacing Clin Electrophysiol ; 39(10): 1108-1115, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27477208

RESUMO

BACKGROUND: Although a ventriculoatrial interval (VAI) of ≤70 ms is used to distinguish atrioventricular nodal reentrant tachycardia from orthodromic atrioventricular reciprocating tachycardia (AVRT), a VAI of ≤70 ms is sometimes observed in cases of AVRT. The study aimed to evaluate the short VAI that is seen in AVRT and to understand its underlying mechanism. METHODS: Electrophysiologic studies of 46 consecutive patients with AVRT involving an accessory pathway (AP) were examined retrospectively. RESULTS: AP was right sided in seven patients and left sided in 39. A VAI (interval from QRS onset to the earliest intracardiac atrial electrogram recorded by any mapping catheter during AVRT) ≤70 ms during AVRT (short VAI) was observed in eight patients: six with a left lateral AP and two with a left posteroseptal AP. During AVRT involving a left-sided AP, the QRS-V interval (from the earliest QRS onset to the local ventricular electrogram at a site which showed earliest atrial electrogram recorded from the coronary sinus catheter) was significantly shorter (37 ± 7 ms vs 54 ± 13 ms, P = 0.001) and supernormal conduction (QRS duration or the QRS-V interval shortening by ≥10 ms during AVRT) was more frequently seen (63% vs 6%, P = 0.02) in the short VAI group than in the normal VAI group. Furthermore, these parameters were shown to be determinants for short VAI. CONCLUSIONS: A short VAI is sometimes observed during AVRT involving a left-sided AP. The short VAI may be caused by rapid propagation or supernormal conduction between the proximal Purkinje-muscle junction and basal left ventricular myocardium.


Assuntos
Taquicardia Reciprocante/fisiopatologia , Feixe Acessório Atrioventricular/fisiopatologia , Nó Atrioventricular/fisiopatologia , Diagnóstico Diferencial , Eletrofisiologia , Feminino , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia por Reentrada no Nó Atrioventricular/diagnóstico , Taquicardia Reciprocante/diagnóstico
19.
J Interv Card Electrophysiol ; 47(2): 245-252, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27278517

RESUMO

BACKGROUND: The clinical utility of an automated lesion tagging module based on catheter stability information (VisiTag) with the CARTO system during atrial fibrillation (AF) ablation remains to be established. We investigated whether VisiTag-guided extensive encircling pulmonary vein isolation (EEPVI) produces durable lesions. METHODS: The study involved 54 patients undergoing EEPVI for paroxysmal AF. We performed EEPVI guided by the module-generated ablation tags, i.e., "VisiTags," which are point-by-point ablation tags placed on 3D maps. The patients were divided into two groups: those treated under a moderate catheter stability VisiTag setting, i.e., a 3-mm distance limit for at least 5 s and a minimum contact force (CF) of 8 g over 25 % of the set time period with a target force-time integral (FTI) ≥300 g*s (n = 27), and those treated under a strict catheter stability setting, i.e., a 3-mm distance limit for at least 10 s and a minimum CF of 10 g over 50 % of the set time period with a target FTI ≥400 g*s (n = 27). RESULTS: After EEPVI, adenosine triphosphate-provoked dormant PV conduction was observed in six (22 %) patients in the moderate catheter stability group and in one (4 %) patient in the strict catheter stability group (p = 0.1003); the 12.9-month success rate was 81 % in both groups. CONCLUSIONS: The strict catheter stability setting for automated lesion tagging together with a target FTI of >400 g*s, vs. the moderate catheter stability setting with a target FTI of >300 g*s, produces less frequent ATP-provoked PV conduction and yields a comparably high mid-term success rate.


Assuntos
Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Mapeamento Potencial de Superfície Corporal/métodos , Veias Pulmonares/cirurgia , Software , Cirurgia Assistida por Computador/métodos , Algoritmos , Fibrilação Atrial/fisiopatologia , Feminino , Sistema de Condução Cardíaco/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/métodos , Pressão , Veias Pulmonares/fisiopatologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estresse Mecânico , Resultado do Tratamento
20.
J Interv Card Electrophysiol ; 46(3): 325-33, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27221713

RESUMO

PURPOSE: The usefulness of electrogram (EGM)-based information has been reported for assessing lesion transmurality during atrial fibrillation (AF) ablation, but the wall thickness of the pulmonary vein-left atrial (PV-LA) junction has not been considered. We conducted a study to evaluate the relation between PV-LA junction wall thickness and the presence of adenosine triphosphate (ATP)-provoked dormant PV conduction. METHODS: Eighteen AF patients underwent extensive encircling pulmonary vein isolation (EEPVI) with a target CF of >10 g. RF energy was delivered point-by-point at a power setting of 25-30 W for 30 s, and EGM-based information (change in filtered unipolar EGM morphology and bipolar EGM amplitude), decrease in impedance, CF, and CT-based measurement of the PV-LA junction wall thickness were characterized at sites of ATP-provoked dormant conduction. RESULTS: After EEPVI, ATP-induced dormant conduction was observed at 12 of the 288 PV sites (8 segments per ipsilateral PVs × 2 × 18 patients). Of the 974 ablation points, 72 were located at dormant conduction sites and were strongly associated with thickened PV-LA junction walls (1.02± 0.23 vs. 0.86 ± 0.26 mm, p < 0.0001) and decreased impedance (13.3 ± 6.4 vs. 14.9 ± 7.1 Ω, p = 0.0498) but not with EGM-based information or CF. Multivariate analysis identified the thickened PV-LA junction wall as the strongest predictor of dormant conduction. CONCLUSIONS: A thickened PV-LA junction wall is a robust predictor of ATP-provoked dormant conduction; EGM-based information appears to be insufficient for ensuring adequate lesions during CF-guided EEPVI.


Assuntos
Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Eletrocardiografia/efeitos dos fármacos , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Adenosina/administração & dosagem , Eletrocardiografia/métodos , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/métodos , Tamanho do Órgão , Estresse Mecânico , Vasodilatadores/administração & dosagem
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