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1.
Adv Sci (Weinh) ; 10(35): e2304790, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37867208

RESUMO

Further improvement of the performance and stability of inverted perovskite solar cells (PSCs) is necessary for commercialization. Here, ferrocene derivative dibenzoylferrocene (DBzFe) is used as an additive to enhance the performance and stability of MA- and Br- free PSCs. The results show that the introduction of DBzFe not only passivates the defects in the film but also inhibits the ion migration in the film. The final device achieves a power conversion efficiency (PCE) of 23.53%, which is one of the highest efficiencies currently based on self-assembled monolayers (SAMs). Moreover, it maintains more than 96.4% of the original efficiency when running continuously for 400 h at the maximum power point.

3.
ACS Appl Mater Interfaces ; 15(35): 41549-41559, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37606594

RESUMO

This report is on the efficiency enhancement of wide bandgap lead halide perovskite solar cells (WBG Pb-PVK PSCs) consisting of FA0.8Cs0.2PbI1.8Br1.2 as the light-harvesting layer. WGB Pb-PVK PSCs have attracted attention as the top layer of all perovskite-tandem solar cells. Poly[bis(4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA), a conductive polymer, is always used as the hole transporting layer (HTL) for Pb-PVK PSCs. Nevertheless, the hydrophobic surface of the PTAA sometimes destroys the growth of the FA0.8Cs0.2PbI1.8Br1.2 film. On the other hand, the Fermi level of PTAA is not well matched with that of perovskite film. Thus, the PCE of the WBG Pb-based PSCs with PTAA as the HTL was not very high. In this report, the efficiency of the FA0.8Cs0.2PbI1.8Br1.2 is improved by passivating the surface of the PTAA with a monomolecular layer, where the surface becomes hydrophilic, and the band bending of the PTAA layer is improved to cause swift hole collection. Finally, WBG Pb-PVK PSCs (1.77 eV) with 16.52% efficiency are reported.

4.
Rinsho Shinkeigaku ; 63(8): 505-512, 2023 Aug 29.
Artigo em Japonês | MEDLINE | ID: mdl-37518020

RESUMO

A 72-year-old male developed neurological symptoms such as difficulty in charging his electronic money card and making his mobile-phone call ten months before admission. On admission, neurological examination revealed extensive higher brain dysfunction such as impairment in recent memory, executive function disorders, constructional disturbance, agraphia and acalculia. Brain MRI revealed a low intensity lesion on the surface of the cerebral cortex diffusely and symmetrically on T2*-weighted images. MRI images are consistent with superficial siderosis. However, the lack of hemosiderin deposition in the brain stem and cerebellar hemisphere was atypical of the classical type of superficial siderosis. 123I-IMP-SPECT revealed hypoperfusion dominantly in the left hemisphere, particularly in the left frontal and parietal lobes. According to the Boston criteria, the patient with the cerebral microbleeds and cortical superficial siderosis was diagnosed with probable CAA (cerebral amyloid angiopathy).


Assuntos
Encefalopatias , Angiopatia Amiloide Cerebral , Siderose , Masculino , Humanos , Idoso , Siderose/complicações , Siderose/diagnóstico por imagem , Encefalopatias/patologia , Angiopatia Amiloide Cerebral/complicações , Angiopatia Amiloide Cerebral/diagnóstico por imagem , Angiopatia Amiloide Cerebral/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Imageamento por Ressonância Magnética , Tomografia Computadorizada de Emissão de Fóton Único/efeitos adversos , Hemorragia Cerebral/etiologia
5.
Int Heart J ; 64(4): 535-542, 2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37460322

RESUMO

Rapid reperfusion by primary percutaneous coronary intervention (pPCI) is an established strategy for the treatment of patients with ST-segment elevation myocardial infarction (STEMI). Pre-hospital electrocardiogram (PH-ECG) transmission by the emergency medical services (EMS) facilitates timely reperfusion in these patients. However, evidence regarding the clinical benefits of PH-ECG in individual hospitals is limited.This retrospective, observational study investigated the clinical efficacy of PH-ECG in STEMI patients who underwent pPCI. Of a total of 382 consecutive STEMI patients, 237 were enrolled in the study and divided into 2 groups: a PH-ECG group (n = 77) and non-PH-ECG group (n = 160). Door-to-balloon time (D2BT) was significantly shorter in the PH-ECG group (66 [52-80] min), compared to the non-PH-ECG group (70 [57-88] minutes, P = 0.01). The 30-day all-cause mortality rate was 6% in the PH-ECG group, which was significantly lower than that in the non-PH-ECG group (16%) (P = 0.037, hazard ratio [HR]: 0.38, 95% CI: 0.15-0.98). This trend was particularly evident in severely ill patients when stratified by GRACE score.The use of PH-ECG improved the survival rate of STEMI patients undergoing pPCI due to the improved pre-arrival preparation based on the EMS information. Coordination between EMS and PCI-capable institutes is essential for the management of PH-ECG.


Assuntos
Serviços Médicos de Emergência , Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Intervenção Coronária Percutânea/efeitos adversos , Infarto do Miocárdio/etiologia , Estudos Retrospectivos , Hospitais , Resultado do Tratamento , Eletrocardiografia
6.
Angew Chem Int Ed Engl ; 62(33): e202307228, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37337312

RESUMO

The photoelectric properties of nontoxic Sn-based perovskite make it a promising alternative to toxic Pb-based perovskite. It has superior photovoltaic performance in comparison to other Pb-free counterparts. The facile oxidation of Sn2+ to Sn4+ presents a notable obstacle in the advancement of perovskite solar cells that utilize Sn, as it adversely affects their stability and performance. The study revealed the presence of a Sn4+ concentration on both the upper and lower surfaces of the perovskite layer. This discovery led to the adoption of a bi-interface optimization approach. A thin layer of Sn metal was inserted at the two surfaces of the perovskite layer. The implementation of this intervention yielded a significant decrease in the levels of Sn4+ and trap densities. The power conversion efficiency of the device was achieved at 14.31 % through the optimization of carrier transportation. The device exhibited operational and long-term stability.

7.
Heart Rhythm O2 ; 4(2): 134-146, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36873315

RESUMO

In the setting of structural heart disease, ventricular tachycardia (VT) is typically associated with a re-entrant mechanism. In patients with hemodynamically tolerated VTs, activation and entrainment mapping remain the gold standard for the identification of the critical parts of the circuit. However, this is rarely accomplished, as most VTs are not hemodynamically tolerated to permit mapping during tachycardia. Other limitations include noninducibility of arrhythmia or nonsustained VT. This has led to the development of substrate mapping techniques during sinus rhythm, eliminating the need for prolonged periods of mapping during tachycardia. Recurrence rates following VT ablation are high; therefore, new mapping techniques for substrate characterization are required. Advances in catheter technology and especially multielectrode mapping of abnormal electrograms has increased the ability to identify the mechanism of scar-related VT. Several substrate-guided approaches have been developed to overcome this, including scar homogenization and late potential mapping. Dynamic substrate changes are mainly identified within regions of myocardial scar and can be identified as local abnormal ventricular activities. Furthermore, mapping strategies incorporating ventricular extrastimulation, including from different directions and coupling intervals, have been shown to increase the accuracy of substrate mapping. The implementation of extrastimulus substrate mapping and automated annotation require less extensive ablation and would make VT ablation procedures less cumbersome and accessible to more patients.

8.
J Interv Card Electrophysiol ; 66(1): 215-220, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34319492

RESUMO

BACKGROUND: Ventricular arrhythmia inducibility is one of the ideal endpoints of ventricular tachycardia (VT) ablation. However, it may be challenging to implement programmed electrical stimulation (PES) at the end of the procedure under several circumstances. The long-term outcome of patients who did not undergo PES after VT ablation remains largely unknown. PURPOSE: To investigate the details and long-term outcome of VT ablation in patients who did not undergo PES at the end of the ablation procedure. METHODS: Among 183 VT ablation procedures in patients with structural heart disease who underwent VT ablation using an irrigated catheter, we enrolled those who did not undergo PES after VT ablation. VT ablation strategy involved targeting clinical VT plus pacemap-guided substrate ablation if inducible. When VT was not inducible, substrate-based ablation was performed. The primary endpoint was VT recurrence. RESULTS: In 58 procedures, post-ablation VT inducibility was not assessed. The causes were non-inducibility of sustained VT before ablation (27/58, 46.6%), long procedure time (27.6%, mean 392 min), complications (10.3%), intolerant hemodynamic state (10.3%), and inaccessible or unsafe target (6.9%). With regard to the primary endpoint, 23 recurrences (39.7%) were observed during a mean follow-up period of 2.5 years. Patients with non-inducibility before ablation showed less VT recurrences (4/27, 14.8%) during follow-up than patients with other causes of untested PES after ablation (19/31, 61.2%) (Log-rank < 0.001). CONCLUSIONS: VT recurrence was not observed in approximately 60% of the patients who did not undergo PES at the end of the ablation procedure. PES after VT ablation may be not needed among patients with pre-ablation non-inducibility.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Humanos , Estimulação Elétrica/efeitos adversos , Ablação por Cateter/métodos , Resultado do Tratamento
9.
J Cardiovasc Electrophysiol ; 33(8): 1905-1907, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35775820

RESUMO

A 47-year-old man with symptomatic paroxysmal atrial fibrillation (AF) underwent AF ablation. Activation maps during right atrial pacing and sinus rhythm before the ablation revealed distinctive left atrial (LA) propagations with multiple LA breakthrough sites via epicardial connections. A wide area circumferential ablation was not able to achieve a right pulmonary vein (RPV) isolation and required an inner PV ablation to isolate the RPV. Activation maps during different rhythms before the ablation may be helpful to unmask multiple epicardial connections between the RPV and right atrium.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/cirurgia
10.
Heart Rhythm ; 19(5): 701-709, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35033665

RESUMO

BACKGROUND: An understanding of normal atrial activation during sinus rhythm can inform catheter ablation strategies to avoid deleterious impacts of ablation lesions on atrial conduction and mechanics. OBJECTIVE: The purpose of this study was to describe how the sinus node impulse originates, propagates, and collides in right and left atria with normal voltage. METHODS: Fifty consecutive patients undergoing catheter ablation of atrial fibrillation with endocardial atrial voltage >0.5 mV during high-density 3-dimensional mapping were studied. RESULTS: Sinus node exits varied among patients along a lateral oblique arc extending from the anterior aspect of the superior vena cava (SVC) to the mid-posterior wall of the right atrium (RA). Conduction slowing or block at one of the smooth components that faces the crista terminalis was observed in 54% of cases, including complete block at the SVC musculature and systemic venous sinus in 6% of cases. Depending on these 2 key features of RA activation, interatrial conduction was mediated by the Bachmann bundle (64%) and posterior bundles (54%), with an overlap of the resulting left atrial breakthrough location. Wavefront collision was consistently observed at 3 sites: the septal aspect of the cavotricuspid isthmus, and the lower aspects of the dome and of the mitral isthmus. CONCLUSION: During sinus rhythm, atrial activation occurs via distinct sequences mediated by a complex interaction of anatomic factors.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Átrios do Coração , Humanos , Nó Sinoatrial , Veia Cava Superior/patologia
11.
Heart Rhythm ; 19(1): 102-112, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34534699

RESUMO

BACKGROUND: Detailed effects of electrode size on electrograms (EGMs) have not been systematically examined. OBJECTIVES: We aimed to elucidate the effect of electrode size on EGMs and investigate an optimal configuration of electrode size and interelectrode spacing for gap detection and far-field reduction. METHODS: This study included 8 sheep in which probes with different electrode size and interelectrode spacing were epicardially placed on healthy, fatty, and lesion tissues for measurements. Between 3 electrode sizes (0.1 mm/0.2 mm/0.5 mm) with 3 mm spacing. As indices of capability in gap detection and far-field reduction, in different electrode sizes (0.1 mm/0.2 mm/0.5 mm) and interelectrode spacing (0.1 mm/0.2 mm/0.3 mm/0.5 mm/3 mm) and the optimized electrode size and interelectrode spacing were determined. Compared between PentaRay and the optimal probe determined in study 2. RESULTS: Study 1 demonstrated that unipolar voltage and the duration of EGMs increased as the electrode size increased in any tissue (P < .001). Bipolar EGMs had the same tendency in healthy/fat tissues, but not in lesions. Study 2 showed that significantly higher gap to lesion volume ratio and healthy to fat tissue voltage ratio were provided by a smaller electrode (0.2 mm or 0.3 mm electrode) and smaller spacing (0.1 mm spacing), but 0.3 mm electrode/0.1 mm spacing provided a larger bipolar voltage (P < .05). Study 3 demonstrated that 0.3 mm electrode/0.1 mm spacing provided less deflection with more discrete EGMs (P < .0001) with longer and more reproducible AF cycle length (P < .0001) compared to PentaRay. CONCLUSION: Electrode size affects both unipolar and bipolar EGMs. Catheters with microelectrodes and very small interelectrode spacing may be superior in gap detection and far-field reduction. Importantly, this electrode configuration could dramatically reduce artifactual complex fractionated atrial electrograms and may open a new era for AF mapping.


Assuntos
Eletrodos , Técnicas Eletrofisiológicas Cardíacas/instrumentação , Animais , Ablação por Cateter , Modelos Animais de Doenças , Desenho de Equipamento , Feminino , Carneiro Doméstico
12.
Lasers Med Sci ; 37(3): 1567-1573, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34436695

RESUMO

Excimer laser coronary atherectomy (ELCA) is an effective treatment to remove intracoronary thrombi. In the present study, we compared in-hospital mortality in patients with acute myocardial infarction (AMI) who underwent conventional treatment and conventional treatment plus ELCA. Among 656 patients who were admitted to our hospital through the Tokyo CCU Network, 104 patients with AMI who were treated by percutaneous coronary intervention between January 2013 and December 2016 met inclusions criteria and underwent conventional treatment with ELCA (ELCA group) and 89 underwent conventional treatment alone (conventional group). We retrospectively evaluated in-hospital mortality within 30 days and used propensity score (PS) matching to reduce assignment bias and multivariate analysis to detect the predictors of in-hospital mortality. In-hospital mortality rate was significantly lower in the ELCA group before and after PS matching (2.9% vs. 13.5%, p = 0.006 before PS matching, and 2.8% vs. 14.1%, p = 0.016 after PS matching). After PS matching, ß-blocker or statins use, incidence of shock, Killip classification, and door-to-balloon time were not significantly different. A multivariate logistic regression analysis identified ELCA, dyslipidemia, shock, and left ventricular ejection fraction as independent predictors of in-hospital mortality (odds ratio (OR), 0.147, 95% confidence interval [CI], 0.022-0.959, p = 0.045; OR, 0.077, 95% CI, 0.007-0.805, p = 0.032; OR, 6.494, 95% CI, 1.228-34.34, p = 0.028; OR, 0.890, 95% CI, 0.828-0.957, p = 0.002, respectively). Our data indicate that ELCA with the small diameter and low level emission may reduce the in-hospital mortality compared to conventional methods in patients with AMI in drug-eluting stent era.


Assuntos
Aterectomia Coronária , Stents Farmacológicos , Infarto do Miocárdio , Aterectomia Coronária/efeitos adversos , Angiografia Coronária , Humanos , Lasers de Excimer/efeitos adversos , Infarto do Miocárdio/cirurgia , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
13.
Pacing Clin Electrophysiol ; 45(2): 219-228, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34919281

RESUMO

INTRODUCTION: Electrogram (EGM) fractionation is often associated with diseased atrial tissue; however, mechanisms for fractionation occurring above an established threshold of 0.5 mV have never been characterized. We sought to investigate during sinus rhythm (SR) the mechanisms underlying bipolar EGM fractionation with high-density mapping in patients with atrial fibrillation (AF). METHODS: Forty-five patients undergoing AF ablation (73% paroxysmal, 27% persistent) were mapped at high density (18562 ± 2551 points) during SR (Rhythmia). Only bipolar EGMs with voltages above 0.5 mV were considered for analysis. When fractionation (> 40 ms and >4 deflections) was detected, we classified the mechanisms as slow conduction, wave-front collision, or a pivot point. The relationship between EGM duration and amplitude, and tissue anisotropy and slow conduction, was then studied using a computational model. RESULTS: Of the 45 left atria analyzed, 133 sites of EGM fragmentation were identified with voltages above 0.5 mV. The most frequent mechanism (64%) was slow conduction (velocity 0.45 m/s ± 0.2) with mean EGM voltage of 1.1 ± 0.5 mV and duration of 54.9 ± 9.4 ms. Wavefront collision was the second most frequent (19%), characterized by higher voltage (1.6 ± 0.9 mV) and shorter duration (51.3 ± 11.3 ms). Pivot points (9%) were associated with the highest degree of fractionation with 70.7 ± 6.6 ms and 1.8 ± 1 mV. In 10 sites (8%) fractionation was unexplained. The EGM duration was significantly different among the 3 mechanisms (p = .0351). CONCLUSION: In patients with a history of AF, EGM fractionation can occur at amplitudes > 0.5 mV when in SR in areas often considered not to be diseased tissue. The main mechanism of EGM fractionation is slow conduction, followed by wavefront collision and pivot sites.


Assuntos
Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Ablação por Cateter , Técnicas Eletrofisiológicas Cardíacas , Idoso , Simulação por Computador , Mapeamento Epicárdico , Feminino , Humanos , Itália , Masculino
14.
Rinsho Shinkeigaku ; 61(11): 743-749, 2021 Nov 24.
Artigo em Japonês | MEDLINE | ID: mdl-34657921

RESUMO

A 68-year-old man with a 2-month history of progressive weakness and spontaneous pain in proximal limb muscles presented to our hospital with a dropped head. He started experiencing progressive dysphagia several days before admission. On admission, he had muscle weakness of the limbs and neck extensors with edema and induration in distal extremities. Laboratory tests showed elevation of muscle enzymes. FDG-PET/CT demonstrated multiple hypermetabolic lymph nodes, but the primary site was not identified; thus, metastatic carcinoma of unknown primary origin was considered. The patient was diagnosed with anti-nuclear matrix protein 2 antibody-positive paraneoplastic myopathy based on serum tests. Histological findings of the left biceps brachii muscle biopsy revealed severe variation in fiber size and perifascicular myofiber atrophy. Myofibers exhibited myxovirus resistance protein A expression predominantly in the perifascicular region. Following intravenous methylprednisolone pulse therapy and intravenous immunoglobulin, the patient's muscle strength improved with normalization of muscle enzyme levels. The dropped head was considered to have resulted from the preferential involvement of neck extensors based on the observed FDG-PET/CT uptake in neck extensors.


Assuntos
Dermatomiosite , Doenças Musculares , Idoso , Dor no Peito , Dermatomiosite/tratamento farmacológico , Fluordesoxiglucose F18 , Humanos , Masculino , Músculos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
15.
J Arrhythm ; 37(5): 1295-1302, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34621428

RESUMO

BACKGROUND: Previous studies have demonstrated that some patients have spontaneous right atrium (RA)-superior vena cava (SVC) conduction block, which could be utilized to isolate the SVC effectively by using the Rhythmia mapping system (Boston Scientific). However, employing this approach for SVC isolation using the CARTO electroanatomical mapping system (Biosense Webster) has not yet been clarified. This study aimed to evaluate the safety and efficacy of SVC isolation using the extended early meets late (EEML) tool with the CARTO system. METHODS: The patients who underwent SVC isolation using the CARTO system were enrolled in this study. The RA-SVC conduction block was visualized with an EEML tool. We prospectively assessed the safety and efficacy of SVC isolation using this system. RESULTS: We analyzed 54 patients, and all SVCs were successfully isolated with no complications. Altogether, 44 patients (81.5%) had spontaneous RA-SVC conduction block, and the remaining 10 patients (18.5%) did not. The block group required fewer radiofrequency deliveries for the SVC isolation than the nonblock group (10.7 ± 5.0 vs 15.5 ± 4.8, P = .009). The size of the isolated area in the block group was larger than that in the nonblock group (15.2 ± 5.1 cm2 vs 12.4 ± 2.5 cm2, P = .017). CONCLUSIONS: Approximately 80% of the patients in this study developed a spontaneous RA-SVC conduction block, which might contribute to shortening the time of ablation and avoiding complications.

16.
J Arrhythm ; 37(4): 1007-1014, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34386126

RESUMO

BACKGROUND: The termination of bi-atrial tachycardia (BiAT) via the ablation of the Bachmann's bundle (BB) and mitral isthmus (MI) has been previously reported; however, the strategy and long-term results of catheter ablation for BiAT remain unclear. METHODS: The data of nine patients with BiAT who underwent low voltage zone (LVZ) ablation of the left atrial anterior wall (LAAW) after pulmonary vein isolation were reviewed. Patients with a P wave duration <100 ms during sinus rhythm underwent MI ablation and those with a P wave duration >100 ms underwent BB ablation. RESULTS: MI ablation was performed in three patients and six patients underwent BB ablation. The difference in the P wave duration before and after ablation was significantly different between the ablation sites (MI group: 5.0 ms difference; BB group; 38.5 ms difference; P = .024). The P wave duration was prolonged by >20 ms and was 120 ms or more after ablation in 5/6 patients who underwent BB ablation. The total recurrence rate was 11.0% (mean: 26.9 months). CONCLUSION: The recurrence of BiAT after MI or BB ablation is low. When BB ablation was performed, the P wave duration was prolonged by >20 ms and was at least 120 ms after the ablation, which may be an endpoint that can be used to measure the success of the ablation.

17.
Heart Rhythm ; 18(11): 1951-1958, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34217842

RESUMO

BACKGROUND: Mitral isthmus gaps have been ascribed to an epicardial musculature anatomically related to the great cardiac vein (GCV) and the vein of Marshall (VOM). Their lumen offers an access for radiofrequency application or ethanol infusion, respectively. OBJECTIVE: The purpose of this study was to evaluate the frequency of mitral isthmus gaps accessible via the GCV lumen, to assess their location around the GCV circumference, and to propose an efficient ablation strategy when present. METHODS: One hundred consecutive patients underwent VOM ethanol infusion (step 1) and endocardial linear ablation from the mitral annulus to the left inferior pulmonary vein (step 2). In cases of mitral isthmus gap, endovascular ablation of the GCV anchored wall facing the left atrium was systematically performed (step 3), while the opposite GCV free wall was targeted in case of block failure only (step 4). RESULTS: After VOM ethanol infusion and endocardial ablation, mitral isthmus block occurred in 51 patients (51%). Pacing maneuvers and activation sequences demonstrated an epicardial gap via the VOM in 2 patients (2%) and via the GCV in 47 patients (47%). In the latter case, block was achieved at the GCV anchored wall in 42 patients (89%) and the GCV free wall in 5 patients (11%). Global success rate of mitral isthmus block was 98%. No tamponade occurred. CONCLUSION: With the advent of VOM ethanol infusion, residual mitral isthmus gaps are mostly eliminated within the first centimeter of the GCV. Thorough mapping of the entire circumference of the GCV wall can help identify these epicardial gaps.


Assuntos
Fibrilação Atrial/terapia , Ablação por Cateter , Vasos Coronários/anatomia & histologia , Etanol/administração & dosagem , Músculo Liso Vascular/anatomia & histologia , Veias/anatomia & histologia , Idoso , Mapeamento Epicárdico , Feminino , Bloqueio Cardíaco/etiologia , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Pericárdio/anatomia & histologia
18.
J Cardiovasc Electrophysiol ; 32(9): 2451-2461, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34314087

RESUMO

INTRODUCTION: Human atria comprise distinct layers. One layer can bypass another, and lead to a downstream centrifugal propagation at their interface. We sought to characterize anatomical substrates, electrophysiological properties, and ablation outcomes of "pseudo-focal" atrial tachycardias (ATs), defined as macroreentrant ATs mimicking focal ATs. METHODS AND RESULTS: We retrospectively analyzed left atrial ATs showing centrifugal propagation with postpacing intervals (PPIs) after entrainment pacing suggestive of a macroreentrant mechanism. A total of 22 patients had pseudo-focal ATs consisting of 15 perimitral and 7 roof-dependent flutters. A low-voltage area was consistently found at the collision site and colocalized with distinct anatomical structures like the: (1) coronary sinus-great cardiac vein bundle (27%), (2) vein of Marshall bundle (18%), (3) Bachmann bundle (27%), (4) septopulmonary bundle (18%), and (5) fossa ovalis (9%). The mean missing tachycardia cycle length (TCL) was 65 ± 31 ms (22%) on the endocardial activation map. PPI was 0 [0-15] ms and 0 [0-21] ms longer than TCL at the breakthrough site and the opposite site, respectively. While feasible in 21 pseudo-focal ATs (95%), termination was better achieved by blocking the anatomical isthmus than ablating the breakthrough site [20/21 (95%) vs. 1/5 (20%); p < .001]. CONCLUSION: Perimitral and roof-dependent flutters with centrifugal propagation are favored by a low-voltage area located at well-identified anatomical structures. Comprehensive entrainment pacing maneuvers are crucial to distinguish pseudo-focal ATs from true focal ATs. Blocking the anatomical isthmus is a better therapeutic option than ablating the breakthrough site.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Taquicardia Supraventricular , Fibrilação Atrial/cirurgia , Átrios do Coração/cirurgia , Humanos , Estudos Retrospectivos , Taquicardia , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/cirurgia , Resultado do Tratamento
19.
Heart Rhythm ; 18(7): 1115-1121, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33812085

RESUMO

BACKGROUND: Little is known about persistent atrial fibrillation (AF) ablation in patients with cardiac laminopathy (CLMNA). OBJECTIVES: We aimed to characterize atrial electrophysiological properties and to assess the long-term outcomes of persistent AF ablation in patients with CLMNA. METHODS: All patients with CLMNA referred in our center for persistent AF ablation were retrospectively included. Left atrial (LA) volume, left atrial appendage (LAA) cycle length, interatrial conduction delay, and LA voltage amplitude were analyzed during the ablation procedure. Sinus rhythm maintenance and LA contractile function were assessed during long-term follow-up. RESULTS: From 2011 to 2020, 8 patients were included. The mean age was 47 ± 14 years, and 3 patients (38%) were women. The LA volume was 205.8 ± 43.7 mL; the LAA AF cycle length was 250.7 ± 85.6 ms; and the interatrial conduction delay was 296.5 ± 110.1 ms. Large low-voltage areas (>50% of the LA surface; <0.5 mV electrogram) were recorded in all 8 patients. Two patients had inadvertent LAA disconnection during ablation. All A waves recorded by pulsed Doppler in sinus rhythm were <30 cm/s before and after AF ablation. Early arrhythmia recurrence was recorded in 7 patients (87%) (time to recurrence 4 ± 4 months; 1.5 procedures per patient). After a mean follow-up of 4.4 ± 3.2 years, 4 patients underwent implantable cardioverter-defibrillator therapy for life-threatening ventricular arrhythmia and 3 patients finally underwent heart transplantation. CONCLUSION: Patients with persistent AF afflicted by CLMNA exhibit severe LA impairment because of large low-voltage areas, prolonged conduction velocity, and reduced contractile function. Ablation procedures have a limited effect with a high recurrence rate.


Assuntos
Fibrilação Atrial/diagnóstico , Função do Átrio Esquerdo/fisiologia , Ablação por Cateter/métodos , Técnicas Eletrofisiológicas Cardíacas/métodos , Átrios do Coração/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Adulto , Idoso , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Eletrocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos
20.
J Cardiovasc Electrophysiol ; 32(5): 1461-1463, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33783898

RESUMO

The Accufix bipolar active fixation atrial pacing lead (Model 330-801; Telectronics) can have mechanical complications due to a fracture of its J retention wire. An 80-year-old man had the Accufix atrial pacing lead implanted 29 years prior, and surgical removal was required because a part of the lead was perforating the apex of the right ventricle. Regular follow-up examinations are recommended to eliminate the possibility of protrusion and detachment of the J retention wire, even if the clinical course after implantation is stable for a prolonged period.


Assuntos
Eletrodos Implantados , Marca-Passo Artificial , Idoso de 80 Anos ou mais , Eletrodos Implantados/efeitos adversos , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/cirurgia , Humanos , Masculino , Marca-Passo Artificial/efeitos adversos
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