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2.
Europace ; 21(5): 724-731, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30649273

RESUMO

AIMS: Late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) may define left atrial (LA) anatomy and structural remodelling, and facilitate atrial fibrillation (AF) ablation. We aimed to assess the intra- and inter-observer reproducibility and agreement of LGE-CMR parameters with direct application to AF ablation techniques. METHODS AND RESULTS: One experienced and one non-experienced observer performed complete LGE-CMR data analysis twice, on different days, in 40 randomly selected LGE-CMR examinations [20 performed before ablation (pre-ablation) and 20 performed 3 months after ablation (post-ablation)]. Four additional observers (two experienced and two non-experienced) performed complete LGE-CMR data analysis in a subgroup of 30 patients (15 pre-ablation and 15 post-ablation). All LGE-CMR were performed in sinus rhythm. Intra- and inter-observer reproducibility of LA volume, LA area, and sphericity index (SI) was high: coefficient of variation <10% and intraclass correlation coefficient >0.71. Geometric congruency of repeated reconstruction of LA shape was high: maximal error <5 mm for intra-observer and <8 mm for inter-observer. The precision of scar location increased with extent of scar, and was high (Dice coefficient >0.75) when the scar area was >5 cm2 for a single observer and >15 cm2 for multiple observers. Non-experienced observers performed equally well to experienced observers. CONCLUSION: Late gadolinium enhancement cardiac magnetic resonance measurements of LA area, volume, and SI were reproducible, and geometric congruency of LA shape was high. Location of scar was precise for scar areas >5 cm2 for single observers and >15 cm2 for multiple observers, regardless of the observers' experience. These results may serve as a reference for future studies on the role for substrate-based AF ablation procedures.

3.
Circ Arrhythm Electrophysiol ; 11(12): e006659, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30562102

RESUMO

BACKGROUND: There is limited knowledge about the impact of anatomic gaps as assessed by delayed gadolinium enhancement cardiac magnetic resonance on atrial fibrillation (AF) recurrence after first pulmonary vein (PV) isolation. METHODS: Consecutive patients underwent delayed gadolinium enhancement cardiac magnetic resonance 3 months after radiofrequency circumferential PV isolation. Delayed gadolinium enhancement cardiac magnetic resonance images were assessed from 360 PV resulting in 2880 segments in the 2×8-segment model from 94 patients (52±11 years, 62% paroxysmal AF). Left atria were segmented using dedicated software. Anatomic gap was defined as discontinuation of the ablation line by ≥3 mm. Relative gap length was calculated as absolute gap length divided by the total length of the ablation line. AF recurrence was assessed after a mean follow-up duration of 15±10 months Results: Mean number of anatomic gaps was 5.4 per patient. Recurrence within the first year of ablation was observed in 21 patients with paroxysmal AF (36%) and 19 patients with persistent AF (53%). In the univariate analysis, CHA2DS2-VASc score, AF type, and relative gap length were predictive of recurrence. In the multivariate analysis, only relative gap length was significantly associated with recurrence (hazard ratio, 1.16 [1.02-1.31] per each 10% of gap). CONCLUSIONS: The total relative gap length but not the number of anatomic gaps in the PV ablation line as assessed by delayed gadolinium enhancement cardiac magnetic resonance was associated with AF recurrence 1 year after first PV isolation. An increase of 10% relative gap length increased the likelihood of AF recurrence by 16%.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Gadolínio , Interpretação de Imagem Assistida por Computador/métodos , Imagem Cinética por Ressonância Magnética/métodos , Veias Pulmonares/cirurgia , Adulto , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/mortalidade , Ablação por Cateter/mortalidade , Estudos de Coortes , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Recidiva , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Espanha , Estatísticas não Paramétricas , Análise de Sobrevida
4.
Europace ; 20(12): 1959-1965, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29860416

RESUMO

Aims: Left atrial (LA) fibrosis can be identified by late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) in patients with atrial fibrillation (AF). However, there is limited information about anatomical fibrosis distribution in the left atrium. The aim is to determine whether there is a preferential spatial distribution of fibrosis in the left atrium in patients with AF. Methods and results: A 3-Tesla LGE-CMR was performed in 113 consecutive patients referred for AF ablation. Images were post-processed and analysed using ADAS-AF software (Galgo Medical), which allows fibrosis identification in 3D colour-coded shells. A regional semiautomatic LA parcellation software was used to divide the atrial wall into 12 segments: 1-4, posterior wall; 5-6, floor; 7, septal wall; 8-11, anterior wall; 12, lateral wall. The presence and amount of fibrosis in each segment was obtained for analysis. After exclusions for artefacts and insufficient image quality, 76 LGE-MRI images (68%) were suitable for fibrosis analysis. Segments 3 and 5, closest to the left inferior pulmonary vein, had significantly higher fibrosis (40.42% ± 23.96 and 25.82% ± 21.24, respectively; P < 0.001), compared with other segments. Segments 8 and 10 in the anterior wall contained the lowest fibrosis (2.54% ± 5.78 and 3.82% ± 11.59, respectively; P < 0.001). Age >60 years was significantly associated with increased LA fibrosis [95% confidence interval (CI) 0.19-8.39, P = 0.04] and persistent AF approached significance (95% CI -0.19% to 7.83%, P = 0.08). Conclusion: In patients with AF, the fibrotic area is preferentially located at the posterior wall and floor around the antrum of the left inferior pulmonary vein. Age >60 years was associated with increased fibrosis.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Função do Átrio Esquerdo , Remodelamento Atrial , Meios de Contraste/administração & dosagem , Átrios do Coração/diagnóstico por imagem , Imagem por Ressonância Magnética , Compostos Organometálicos/administração & dosagem , Veias Pulmonares/diagnóstico por imagem , Fatores Etários , Idoso , Fibrilação Atrial/patologia , Fibrilação Atrial/fisiopatologia , Feminino , Fibrose , Átrios do Coração/patologia , Átrios do Coração/fisiopatologia , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Veias Pulmonares/patologia , Veias Pulmonares/fisiopatologia , Fatores de Risco
5.
J Cardiovasc Electrophysiol ; 29(8): 1065-1072, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29722466

RESUMO

INTRODUCTION: The purpose of this study was to compare the anatomical characteristics of scar formation achieved by visual-guided laser balloon (Laser) and radiofrequency (RF) pulmonary vein isolation (PVI), using late-gadolinium-enhanced cardiac magnetic resonance imaging (LGE-CMR). METHODS AND RESULTS: We included 17 patients with paroxysmal or early persistent drug resistant AF who underwent Laser ablation; 2 were excluded due to procedure-related complications. The sample was matched with a historical group of 15 patients who underwent PVI using RF. LGE-CMR sequences were acquired before and 3 months post-PVI. Ablation gaps were defined as pulmonary vein (PV) perimeter sections showing no gadolinium enhancement. The number of ablation gaps was lower in Laser versus RF ablations (median 7 vs. 14, P  =  0.015). Complete anatomical PVI (circumferential scar around PV, without gaps) was more frequently achieved with Laser than with RF (39% vs. 19% of PVs, P  =  0.025). Fewer gaps were present at the superior and anterior left PV and posterior right PV antral regions in the Laser group, compared to RF. Scar extension into the PVs was similar in both groups, although RF produced more extensive ablation scar toward the LA body. AF recurrences at 1 year were similar in both groups (Laser 36% vs. RF 27%, P  =  1.00). CONCLUSIONS: Compared to RF, Laser ablation achieved more complete anatomical PVI, with less LA scar extension. However, AF recurrence appears to be similar after Laser compared to RF ablation. Further studies are needed to assess whether the anatomical advantages of Laser ablation translate into clinical benefit in patients with AF.


Assuntos
Gadolínio , Imagem Cinética por Ressonância Magnética/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Veias Pulmonares/diagnóstico por imagem , Ablação por Radiofrequência/tendências , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Terapia a Laser/efeitos adversos , Terapia a Laser/tendências , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Veias Pulmonares/cirurgia , Ablação por Radiofrequência/efeitos adversos
7.
J Cardiovasc Electrophysiol ; 29(5): 740-746, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29528532

RESUMO

INTRODUCTION: To investigate the relation between left atrial (LA) volume, sphericity, and fibrotic content derived from contrast-enhanced cardiac magnetic resonance imaging (CE-CMR) and their impact on the outcome of catheter ablation for atrial fibrillation (AF). METHODS AND RESULTS: In 83 patients undergoing catheter ablation for AF, CE-CMR was used to assess LA volume, sphericity, and fibrosis. There was a significant correlation between LA volume and sphericity (R  =  0.535, P < 0.001) and between LA volume and fibrosis (R  =  0.241, P  =  0.029). Multivariate analyses demonstrated that LA volume was the strongest independent predictor of AF recurrence after catheter ablation (1.019, P  =  0.018). CONCLUSION: LA volume, sphericity, and fibrosis were closely related; however, LA volume was the strongest predictor of AF recurrence after catheter ablation.


Assuntos
Fibrilação Atrial/cirurgia , Função do Átrio Esquerdo , Remodelamento Atrial , Ablação por Cateter , Átrios do Coração/cirurgia , Potenciais de Ação , Idoso , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/fisiopatologia , Ablação por Cateter/efeitos adversos , Meios de Contraste/administração & dosagem , Feminino , Fibrose , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Frequência Cardíaca , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos/administração & dosagem , Recidiva , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
11.
Europace ; 19(8): 1272-1279, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27940935

RESUMO

Aims: Identification of left atrial (LA) fibrosis through late gadolinium-enhanced cardiac magnetic resonance (LGE-CMR) remains controversial due to the heterogeneity and lack of reproducibility of proposed methods. Our aim is to describe a normalized, reproducible, standardized method to evaluate LA fibrosis through LGE-CMR. Methods and results: Electrocardiogram- and respiratory-gated 3-Tesla LGE-CMR was performed in 10 healthy young volunteers and 30 patients with atrial fibrillation (AF): 10 with paroxysmal AF, 10 with persistent AF, and 10 with a previous AF ablation procedure. Local image intensity ratio (IIR) of the LA was calculated as the absolute pixel intensity to mean blood pool intensity ratio. The healthy atrial tissue threshold was defined in young healthy volunteers (upper limit of normality set at IIR tissue mean plus 2 SDs). Dense atrial scarring was characterized in patients with previous radiofrequency-induced scarring (post-AF ablation patients). Validation groups consisted of patients with paroxysmal and persistent AFs. The upper limit of normal IIR was 1.20; IIR values higher than 1.32 (60% of mean maximum pixel intensity in post-ablation patients) were considered dense scar. Image intensity ratio values between 1.2 and 1.32 identified interstitial fibrosis. Patients with paroxysmal and persistent AFs had less atrial fibrotic tissue compared with post-ablation patients. Endocardial bipolar voltage was correlated to IIR values. Conclusions: An IIR of 1.2 identifies the upper limit of normality in healthy young individuals. An IIR of >1.32 defines dense atrial fibrosis in post-ablation patients. Our results provide a consistent, comparable, and normalized tool to assess atrial arrhythmogenic substrate.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Remodelamento Atrial , Meios de Contraste/administração & dosagem , Átrios do Coração/diagnóstico por imagem , Imagem por Ressonância Magnética/normas , Compostos Organometálicos/administração & dosagem , Potenciais de Ação , Adolescente , Adulto , Idoso , Fibrilação Atrial/patologia , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Técnicas de Imagem de Sincronização Cardíaca , Estudos de Casos e Controles , Ablação por Cateter , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Feminino , Fibrose , Átrios do Coração/patologia , Átrios do Coração/fisiopatologia , Átrios do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Valores de Referência , Reprodutibilidade dos Testes , Adulto Jovem
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