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1.
Echocardiography ; 37(6): 883-890, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32449845

RESUMO

BACKGROUND: Dilatation of the ascending aorta has an important role in the anatomical conformation of interatrial septum (IAS) especially when a patent foramen ovale (PFO) is present. The aim of the study was to investigate the relationship between ascending aortic dilation and PFO-related cryptogenic stroke in a cohort of cryptogenic strokes. METHODS: It is a retrospective, single-center echocardiographic study assessing aortic root dilatation in 315 consecutive patients with cryptogenic stroke between January 2011 and January 2019. Aortic root dilatation was defined by a diameter of the Valsalva sinuses of the proximal aorta >40 mm. Predictive factors of PFO were assessed by a multivariate analysis. Propensity score matching was applied to account for clinical differences. RESULTS: Of the 315 patients, 68 (22%) had an aortic root dilatation and 167 (53%) had a PFO. In the aortic root dilation group, PFO was more often diagnosed (n = 47/68 [69%], vs n = 120/247 [49%], P = .004). In the PFO group with aortic dilatation, IAS was more mobile (n = 37/47[79%] vs n = 69/120[57%], P < .012) and smaller (2.3 ± 0.5 vs 2.5 ± 0.5 mm, P < .009). On multivariate analysis, aortic root dilatation (OR: 2.6; 95% CI [1.2-5.6]; P = .001) and IAS hypermobility (OR: 5.2 95% CI [2.7-10]; P = .001) were associated with PFO. After propensity matching, aortic root dilatation remained strongly associated with PFO (n = 34/107 [32%] vs 15/107[14%], P = .002). CONCLUSION: Aortic root dilation and IAS hypermobility were strongly associated with PFO-related cryptogenic stroke.


Assuntos
Forame Oval Patente , AVC Isquêmico , Acidente Vascular Cerebral , Dilatação , Forame Oval Patente/complicações , Forame Oval Patente/diagnóstico por imagem , Humanos , Pontuação de Propensão , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/complicações
2.
Am J Cardiol ; 211: 79-88, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37898222

RESUMO

Right ventricular systolic dysfunction (RVsD) frequently occurs in patients with ST-elevation myocardial infarction (STEMI). However, the diagnosis depends on the echocardiographic parameters to define RVsD. The right ventricle longitudinal shortening fraction (RV-LSF) is an accurate and reproducible 2-dimensional speckle-tracking parameter associated with clinical events in various pathologies. This study aimed to evaluate the association between RVsD and major adverse cardiovascular event (MACE) occurrence in a cohort of patients with STEMI. Adult patients with STEMI admitted to Amiens University Hospital's cardiovascular intensive care unit between May 2021 and November 2022 who underwent coronary angiography and transthoracic echocardiography within 48 hours of admission were included. RVsD was defined as RV-LSF <20%. The primary outcome was MACE occurrence, including heart failure, myocardial infarction, stroke, and death within 6 months of admission. A multivariable Cox regression analysis with proportional hazard ratio models assessed the association between RVsD and MACEs. In the 164 included patients, 72 (44%) had RVsD and 92 (56%) did not. The RVsD group had a significantly higher proportion of MACEs during the 6-month follow-up (n = 23 of 72, 33%) than the group without RVsD (n = 8 of 92, 9%, p = 0.001). RVsD showed an independent association with MACEs at 6 months (hazard ratio 3.1, 95% confidence interval [CI] 1.35 to 7.30, p = 0.008). Left ventricular ejection fraction <40% and Thrombolysis in Myocardial Infarction score >4 were independently associated with RVsD (odds ratio 2.80, 95% CI 1.34 to 5.98 and odds ratio 2.15, 95% CI 1.18 to 4.39, respectively, p = 0.015). The cumulative risk of MACEs at 6 months was 33% for RV-LSF <20% and 9% for RV-LSF ≥20% (log-rank test p <0.001). RVsD, defined by RV-LSF <20%, is associated with an increased risk of MACEs after STEMI.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Adulto , Humanos , Prognóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Volume Sistólico , Ventrículos do Coração/diagnóstico por imagem , Estudos Prospectivos , Função Ventricular Esquerda , Ecocardiografia/métodos , Infarto do Miocárdio/complicações , Intervenção Coronária Percutânea/efeitos adversos
3.
J Clin Med ; 13(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38398319

RESUMO

Introduction: Right-ventricular-to-pulmonary artery (RV-PA) coupling, measured as the ratio of tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP), has emerged as a predictor factor in patients undergoing transcatheter aortic valvular replacement (TAVR). Right ventricular longitudinal shortening fraction (RV-LSF) outperformed TAPSE as a prognostic parameter in several diseases. We aimed to compare the prognostic ability of two RV-PA coupling parameters (TAPSE/PASP and the RV-LSF/PASP ratio) in identifying MACE occurrences. Method: A prospective and single-center study involving 197 patients who underwent TAVR was conducted. MACE (heart failure, myocardial infarction, stroke, and death within six months) constituted the primary outcome. ROC curve analysis determined cutoff values for RV-PA ratios. Multivariable Cox regression analysis explored the association between RV-PA ratios and MACE. Results: Forty-six patients (23%) experienced the primary outcome. No significant difference in ROC curve analysis was found (RV-LSF/PASP with AUC = 0.67, 95%CI = [0.58-0.77] vs. TAPSE/PASP with AUC = 0.62, 95%CI = [0.49-0.69]; p = 0.16). RV-LSF/PASP < 0.30%.mmHg-1 was independently associated with the primary outcome. The 6-month cumulative risk of MACE was 59% (95%CI = [38-74]) for patients with RV-LSF/PASP < 0.30%.mmHg-1 and 17% (95%CI = [12-23]) for those with RV-LSF/PASP ≥ 0.30%.mmHg-1; (p < 0.0001). Conclusions: In a contemporary cohort of patients undergoing TAVR, RV-PA uncoupling defined by an RV-LSF/PASP < 0.30%.mmHg-1 was associated with MACE at 6 months.

4.
Arch Cardiovasc Dis ; 117(4): 266-274, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423888

RESUMO

BACKGROUND: New-onset atrial fibrillation (NOAF) is a well-known complication of ST-segment elevation myocardial infarction (STEMI), probably due to left atrial (LA) remodelling. LA strain (LAS) can predict NOAF in several cardiovascular diseases. OBJECTIVE: To assess whether LAS predicts NOAF in sinus rhythm patients with STEMI during hospitalization. METHODS: Adults with a STEMI and transthoracic echocardiography performed within 48hours of admission were included. LAS analysis, performed by automated software, recorded LAS during the reservoir phase (LASr), the conduit phase (LAScd) and the contraction phase (LASct). RESULTS: From May 2021 to November 2022, 175 patients were included, 21 (12%) of whom developed NOAF. NOAF patients were older (median [Q1-Q3]: 67 [59-80] vs 59 [51-67]years; P=0.006) and had a higher Thrombolysis In Myocardial Infarction scores (4 [2-7] vs 3 [1-4]; P=0.005). All LAS parameters were significantly impaired in NOAF patients, especially LASr (13.0% [10.5-28.4] vs 36.6% [29.0-44.9]; P=0.001). An LASr cut-off of 27% had a sensitivity of 81% and a specificity of 80% to identify patients with NOAF. In a multivariable model, LASr was significantly associated with NOAF (odds ratio 1.18, 95% confidence interval 1.09-1.26; P=0.003). The cumulative risk of NOAF during hospital stay was 30% (18-43 with LASr<27% and 4% [1.5-8.5] with LASr≥27% [P<0.0001]). CONCLUSION: NOAF is a frequent complication of STEMI. LASr seems helpful for identifying patients at high risk of NOAF during hospitalization.


Assuntos
Fibrilação Atrial , Infarto do Miocárdio , Infarto do Miocárdio com Supradesnível do Segmento ST , Adulto , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Estudos Prospectivos , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/terapia , Infarto do Miocárdio/complicações , Ecocardiografia
5.
Arch Cardiovasc Dis ; 116(5): 240-248, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37032221

RESUMO

BACKGROUND: The first wave of the coronavirus disease 2019 pandemic significantly changed behaviour in terms of access to healthcare. AIM: To assess the effects of the pandemic and initial lockdown on the incidence of acute coronary syndrome and its long-term prognosis. METHODS: Patients admitted for acute coronary syndrome from 17 March to 6 July 2020 and from 17 March to 6 July 2019 were included. The number of admissions for acute coronary syndrome, acute complication rates and 2-year rates of survival free from major adverse cardiovascular events or death from any cause were compared according to the period of hospitalization. RESULTS: In total, 289 patients were included. We observed a 30±3% drop in acute coronary syndrome admissions during the first lockdown, which did not recover in the 2months after it was lifted. At 2years, there were no significant differences in the combined endpoint of major adverse cardiovascular events or death from any cause between the different periods (P=0.34). Being hospitalized during lockdown was not predictive of adverse events during follow-up (hazard ratio 0.87, 95% confidence interval 0.45-1.66; P=0.67). CONCLUSIONS: We did not observe an increased risk of major cardiovascular events or death at 2years from initial hospitalization for patients hospitalized during the first lockdown, adopted in March 2020 in response to the coronavirus disease 2019 pandemic, potentially as a result of the lack of power of the study.


Assuntos
Síndrome Coronariana Aguda , COVID-19 , Humanos , COVID-19/epidemiologia , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/epidemiologia , Síndrome Coronariana Aguda/terapia , Pandemias , Controle de Doenças Transmissíveis , Prognóstico
6.
Pacing Clin Electrophysiol ; 34(7): 837-43, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21418249

RESUMO

BACKGROUND: Pulmonary vein cryoablation (PVC) is a new approach in the treatment of recurrent atrial fibrillation (AF). Computed tomography (CT) can be used to evaluate the left atrium anatomy and PVs dimensions to facilitate the procedure. In radiofrequency procedures, some anatomic variants such as common left (CLPV) or right (CRPV) PV were reported as factors associated with technical procedure difficulties and potential long-term complications. We hypothesized that the absence of CLPV as determined by CT would predict better AF-free survival after PVC. METHODS AND RESULTS: We included 118 consecutive patients (mean age 56 ± 10 years; 77% males) with drug refractory paroxysmal (72%)/persistent (28%) AF, with more than 6 months follow-up, who underwent PVC. On CT scanning images performed within 1 month prior to ablation, we evaluated PV anatomic patterns: presence of CLPV or CRPV. Each patient was evaluated by 24-hour Holter monitoring within 1 and 3 months and all patients were periodically evaluated at 1, 3, and 6 months, and every 6 months thereafter. Patients were asked to record their 12-lead electrocardiogram whenever they experienced symptoms suggestive of AF. Recurrence was defined as AF that lasted at least 30 seconds. CLPV was present in 30 (25%) patients and no patients with CRPV were identified. At the end of the 13 months follow-up, patients with normal PVs had significantly better AF-free survival compared to patients with CLPV (67% vs 50%, P = 0.02). The difference was present in patients with paroxysmal AF (P = 0.008) but not in patients with persistent AF (P = 0.92). CONCLUSION: In patients undergoing cryoballoon PV isolation for AF, the presence of normal PVs pattern is associated with better AF-free survival as compared to atypical PV anatomy with CLPV, particularly in patients with paroxysmal AF.


Assuntos
Fibrilação Atrial/mortalidade , Fibrilação Atrial/cirurgia , Criocirurgia , Veias Pulmonares/anormalidades , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/anatomia & histologia , Veias Pulmonares/diagnóstico por imagem , Taxa de Sobrevida , Tomografia Computadorizada por Raios X
7.
Phys Med Biol ; 52(8): 2277-99, 2007 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-17404469

RESUMO

Electronic portal imagers have promising dosimetric applications in external beam radiation therapy. In this study a patient dose computation algorithm based on Monte Carlo (MC) simulations and on portal images is developed and validated. The patient exit fluence from primary photons is obtained from the portal image after correction for scattered radiation. The scattered radiation at the portal imager and the spectral energy distribution of the primary photons are estimated from MC simulations at the treatment planning stage. The patient exit fluence and the spectral energy distribution of the primary photons are then used to ray-trace the photons from the portal image towards the source through the CT geometry of the patient. Photon weights which reflect the probability of a photon being transmitted are computed during this step. A dedicated MC code is used to transport back these photons from the source through the patient CT geometry to obtain patient dose. Only Compton interactions are considered. This code also produces a reconstructed portal image which is used as a verification tool to ensure that the dose reconstruction is reliable. The dose reconstruction algorithm is compared against MC dose calculation (MCDC) predictions and against measurements in phantom. The reconstructed absolute absorbed doses and the MCDC predictions in homogeneous and heterogeneous phantoms agree within 3% for simple open fields. Comparison with film-measured relative dose distributions for IMRT fields yields agreement within 3 mm, 5%. This novel dose reconstruction algorithm allows for daily patient-specific dosimetry and verification of patient movement.


Assuntos
Modelos Biológicos , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Tomografia Computadorizada por Raios X/métodos , Simulação por Computador , Humanos , Método de Monte Carlo , Dosagem Radioterapêutica , Eficiência Biológica Relativa , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Med Phys ; 33(11): 4320-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17153411

RESUMO

Kilovoltage (kV) cone beam computed tomography (CBCT) images suffer from a substantial scatter contribution. In this study, Monte Carlo (MC) simulations are used to evaluate the scattered radiation present in projection images. These predicted scatter distributions are also used as a scatter correction technique. Images were acquired using a kV CBCT bench top system. The EGSnrc MC code was used to model the flat panel imager, the phantoms, and the x-ray source. The x-ray source model was validated using first and second half-value layers (HVL) and profile measurements. The HVLs and the profile were found to agree within 3% and 6%, respectively. MC simulated and measured projection images for a cylindrical water phantom and for an anthropomorphic head phantom agreed within 8% and 10%. A modified version of the DOSXYZnrc MC code was used to score phase space files with identified scattered and primary particles behind the phantoms. The cone angle, the source-to-detector distance, the phantom geometry, and the energy were varied to determine their effect on the scattered radiation distribution. A scatter correction technique was developed in which the MC predicted scatter distribution is subtracted from the projections prior to reconstruction. Preliminary testing of the procedure was done with an anthropomorphic head phantom and a contrast phantom. Contrast and profile measurements were obtained for the scatter corrected and noncorrected images. An improvement of 3% for contrast between solid water and a liver insert and 11% between solid water and a Teflon insert were obtained and a significant reduction in cupping and streaking artifacts was observed.


Assuntos
Algoritmos , Modelos Biológicos , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiometria/métodos , Tomografia Computadorizada Espiral/métodos , Encéfalo/diagnóstico por imagem , Simulação por Computador , Humanos , Modelos Estatísticos , Método de Monte Carlo , Imagens de Fantasmas , Doses de Radiação , Reprodutibilidade dos Testes , Espalhamento de Radiação , Sensibilidade e Especificidade , Tomografia Computadorizada Espiral/instrumentação
9.
J Am Coll Cardiol ; 43(10): 1853-60, 2004 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-15145111

RESUMO

OBJECTIVES: We sought to assess hydroquinidine (HQ) efficacy in selected patients with Brugada syndrome (BrS). BACKGROUND: Management of asymptomatic patients with BrS and inducible arrhythmias remains a key issue. Effectiveness of class Ia antiarrhythmic drugs, which inhibit the potassium transient outward current of the action potential, has been suggested in BrS. METHODS: From a cohort of 106 BrS patients, we studied 35 who received HQ (32 men; mean age 48 +/- 11 years). Patients had asymptomatic BrS and inducible arrhythmia (n = 31) or multiple appropriate shocks from an implantable cardioverter-defibrillator (ICD) (n = 4). Asymptomatic patients with inducible arrhythmia underwent electrophysiologic (EP)-guided therapy. When ventricular tachycardia (VT)/ventricular fibrillation (VF) inducibility was not prevented, or in case of HQ intolerance, an ICD was placed. RESULTS: Hydroquinidine prevented VT/VF inducibility in 76% of asymptomatic patients who underwent EP-guided therapy. Syncope occurred in two of the 21 patients who received long-term (17 +/- 13 months) HQ therapy (1 syncope associated with QT interval prolongation and 1 unexplained syncope associated with probable noncompliance). In asymptomatic patients who received an ICD (n = 10), one appropriate shock occurred during a follow-up period of 13 +/- 8 months. In patients with multiple ICD shocks, HQ prevented VT/VF recurrence in all cases during a mean follow-up of 14 +/- 8 months. CONCLUSIONS: Hydroquinidine therapy prevented VT/VF inducibility in 76% of asymptomatic patients with BrS and inducible arrhythmia, as well as VT/VF recurrence in all BrS patients with multiple ICD shocks. These preliminary data suggest that preventive treatment by HQ may be an alternative strategy to ICD placement in asymptomatic patients with BrS and inducible arrhythmia.


Assuntos
Antiarrítmicos/uso terapêutico , Arritmias Cardíacas/tratamento farmacológico , Quinidina/análogos & derivados , Quinidina/uso terapêutico , Adolescente , Adulto , Idoso , Arritmias Cardíacas/complicações , Estudos de Coortes , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Fibrilação Ventricular/etiologia , Fibrilação Ventricular/prevenção & controle
10.
Am Heart J ; 148(2): 312-7, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15309002

RESUMO

BACKGROUND: In order to assess the preventive effects of right atrial septal pacing on atrial fibrillation (AF) in patients with sinus node dysfunction, we conducted a prospective randomized controlled study in patients requiring atrial pacing. METHODS: The inclusion criterion was the presence of a sinus node dysfunction with or without episodes of AF. Pacing sites were randomized to either the right atrial septum or appendage. Patients with permanent AF or with atrioventricular (AV) block without sinus node dysfunction were excluded. Patients were discharged at a pacing rate of 65 beats per minute after setting of the optimal AV delay. The antiarrhythmic therapy remained unchanged until the first recurrence of AF. Sequential analyses were performed with the triangular test. RESULTS: Mean baseline characteristics were not different between the septum (n = 57) and the appendage (n = 67) groups. The triangular test evidenced a lack of effect of septal pacing at the last sequential analysis. The rates of AF-free survival were not different between the septum and the appendage group (65% vs 64%, P =.28). In the subgroup of patients with at least 1 episode of AF 3 months before pacing, AF-free survival was increased by atrial septal pacing (70% vs 40%, P =.018). The mean follow-up was 16 +/- 13 months (range, 1-54). CONCLUSIONS: Atrial septal pacing does not have a preventive effect on the occurrence of AF in patient requiring atrial pacing for sinus node dysfunction. Subgroup analysis suggests that atrial septal pacing may benefit patients with >or=1 episode of AF in the 3 months preceding pacing.


Assuntos
Arritmias Cardíacas/terapia , Fibrilação Atrial/prevenção & controle , Estimulação Cardíaca Artificial , Idoso , Estimulação Cardíaca Artificial/métodos , Intervalo Livre de Doença , Feminino , Átrios do Coração , Septos Cardíacos , Humanos , Masculino , Estudos Prospectivos , Prevenção Secundária , Nó Sinoatrial
11.
Am J Cardiol ; 94(2): 230-3, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15246910

RESUMO

To determine the prevalence of drug-induced Brugada's syndrome (BrS) electrocardiograms (ECGs) in a healthy population, a sodium channel blockade challenge was performed in previously identified subjects with BrS-compatible (BrC) ECGs. These subjects were detected in 1,000 normal patients in whom first ECGs were systematically recorded. Because of the intermittent nature of electrocardiographic modifications in BrS, second ECGs were also recorded in a representative sample of the population presenting with first ECGs with normal results. The prevalence of typical drug-induced BrS ECGs was 5 of the 1,000 patients. This value was fivefold greater than the reported prevalence of spontaneous BrS ECGs in the healthy population.


Assuntos
Bloqueio de Ramo/epidemiologia , Eletrocardiografia , Fibrilação Ventricular/epidemiologia , Adulto , Ajmalina/farmacologia , Antiarrítmicos/farmacologia , Bloqueio de Ramo/genética , Feminino , Humanos , Masculino , Canal de Sódio Disparado por Voltagem NAV1.5 , Polimorfismo Conformacional de Fita Simples , Estudos Prospectivos , Canais de Sódio/efeitos dos fármacos , Canais de Sódio/genética , Síndrome , Fibrilação Ventricular/genética
13.
Med Phys ; 40(11): 111722, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24320430

RESUMO

PURPOSE: This study (1) examines a variety of real-world cases where systematic errors were not detected by widely accepted methods for IMRT/VMAT dosimetric accuracy evaluation, and (2) drills-down to identify failure modes and their corresponding means for detection, diagnosis, and mitigation. The primary goal of detailing these case studies is to explore different, more sensitive methods and metrics that could be used more effectively for evaluating accuracy of dose algorithms, delivery systems, and QA devices. METHODS: The authors present seven real-world case studies representing a variety of combinations of the treatment planning system (TPS), linac, delivery modality, and systematic error type. These case studies are typical to what might be used as part of an IMRT or VMAT commissioning test suite, varying in complexity. Each case study is analyzed according to TG-119 instructions for gamma passing rates and action levels for per-beam and/or composite plan dosimetric QA. Then, each case study is analyzed in-depth with advanced diagnostic methods (dose profile examination, EPID-based measurements, dose difference pattern analysis, 3D measurement-guided dose reconstruction, and dose grid inspection) and more sensitive metrics (2% local normalization/2 mm DTA and estimated DVH comparisons). RESULTS: For these case studies, the conventional 3%/3 mm gamma passing rates exceeded 99% for IMRT per-beam analyses and ranged from 93.9% to 100% for composite plan dose analysis, well above the TG-119 action levels of 90% and 88%, respectively. However, all cases had systematic errors that were detected only by using advanced diagnostic techniques and more sensitive metrics. The systematic errors caused variable but noteworthy impact, including estimated target dose coverage loss of up to 5.5% and local dose deviations up to 31.5%. Types of errors included TPS model settings, algorithm limitations, and modeling and alignment of QA phantoms in the TPS. Most of the errors were correctable after detection and diagnosis, and the uncorrectable errors provided useful information about system limitations, which is another key element of system commissioning. CONCLUSIONS: Many forms of relevant systematic errors can go undetected when the currently prevalent metrics for IMRT∕VMAT commissioning are used. If alternative methods and metrics are used instead of (or in addition to) the conventional metrics, these errors are more likely to be detected, and only once they are detected can they be properly diagnosed and rooted out of the system. Removing systematic errors should be a goal not only of commissioning by the end users but also product validation by the manufacturers. For any systematic errors that cannot be removed, detecting and quantifying them is important as it will help the physicist understand the limits of the system and work with the manufacturer on improvements. In summary, IMRT and VMAT commissioning, along with product validation, would benefit from the retirement of the 3%/3 mm passing rates as a primary metric of performance, and the adoption instead of tighter tolerances, more diligent diagnostics, and more thorough analysis.


Assuntos
Radiometria/métodos , Radioterapia de Intensidade Modulada/métodos , Algoritmos , Raios gama , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Imagens de Fantasmas , Controle de Qualidade , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Reprodutibilidade dos Testes , Incerteza
14.
Arch Cardiovasc Dis ; 105(11): 578-86, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23177486

RESUMO

BACKGROUND: 'J waves' have been associated with idiopathic ventricular fibrillation (VF) and have also been described in patients with ischaemic VF. AIMS: Our aim was to determine whether inferior and/or lateral 'J waves' were associated with the occurrence of VF or in hospital mortality during acute coronary syndrome (ACS). METHODS: Fifty-three patients (mean age 52 ± 10 years) experienced cardiac arrest due to VF during the first 48 hours of an ACS. These patients were entered in a retrospective case-control study. The control group was matched for age and sex and included 106 patients who experienced an ACS but without VF. RESULTS: 'J waves' were more frequent in the study group than in the control group (62% vs. 39%; P=0.006). 'J waves' (odds ratio [OR] 3.3, 95% confidence interval [CI] 1.5-7.1; P=0.001) and left ventricular ejection fraction<40% (53% vs. 14%; P<0.001) (OR 7.9, 95% CI 3.5-18.0; P=0.001) were associated with VF. Inhospital mortality was 15.1% in the study group versus 0.9% in the control group (OR 18.7, 95% CI 2.2-157.5; P=0.008). VF (OR 18.3, 95% CI 2.3-835.9; P<0.001) and the presence of 'J waves' (OR 15.9. 95% CI 2.4-∞; P<0.001) were predictive of inhospital mortality. In patients who experienced VF, inhospital mortality was 24% when 'J waves' were observed and 0% when 'J waves' were absent (P=0.02). CONCLUSIONS: Inferior and lateral 'J waves' were observed more frequently in patients who experienced cardiac arrest due to VF associated with ACS than in the absence of cardiac arrest and were associated with higher inhospital mortality.


Assuntos
Síndrome Coronariana Aguda/complicações , Eletrocardiografia , Fibrilação Ventricular/fisiopatologia , Síndrome Coronariana Aguda/fisiopatologia , Síndrome Coronariana Aguda/terapia , Adulto , Bloqueio de Ramo/complicações , Bloqueio de Ramo/fisiopatologia , Estudos de Casos e Controles , Comorbidade , Feminino , Parada Cardíaca/etiologia , Parada Cardíaca/mortalidade , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Estudos Retrospectivos , Fatores de Risco , Método Simples-Cego , Fibrilação Ventricular/etiologia , Fibrilação Ventricular/mortalidade
15.
Int J Cardiol ; 150(3): e107-9, 2011 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-20223536

RESUMO

Congenital coronary artery fistula (CAF) is a rare disease. We report a case of a 58-year-old man having a complex coronary to pulmonary artery fistula associated with a large saccular aneurysm originated from the terminal portion of the right coronary artery. An endovascular approach was adopted in order to prevent aneurysmal rupture without need of complete closure of the fistula. We suggest transcatheter embolization as an alternative technique for aneurysmal formation closure in asymptomatic patients with complex CAF complicated with aneurysmal formation if it is not necessary to obtain a complete CAF closure.


Assuntos
Fístula Artério-Arterial/terapia , Doenças Assintomáticas/terapia , Aneurisma Coronário/terapia , Anomalias dos Vasos Coronários/terapia , Embolização Terapêutica/métodos , Artéria Pulmonar/anormalidades , Fístula Artério-Arterial/diagnóstico por imagem , Aneurisma Coronário/diagnóstico por imagem , Anomalias dos Vasos Coronários/diagnóstico por imagem , Gerenciamento Clínico , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagem , Radiografia
16.
Arch Cardiovasc Dis ; 104(2): 70-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21402340

RESUMO

BACKGROUND: Systematic use of a 28mm balloon has been proposed for pulmonary vein cryoisolation in patients with atrial fibrillation. OBJECTIVE: To assess the results of a dual balloon size strategy using a 23 or 28mm cryoballoon catheter for pulmonary vein isolation. METHODS: A total of 118 patients (mean age 56 ± 10 years) with paroxysmal (n=85) or persistent atrial fibrillation (n=33) were enrolled. Patients with four pulmonary veins<20mm in diameter were isolated with a 23mm cryoballoon (n=29); patients with one pulmonary vein diameter ≥20mm were isolated with a 28mm cryoballoon (n=89). RESULTS: No significant difference in procedural variables was observed between the two groups. AF-free survival, after a mean follow-up of 19.9 ± 5 months, was similar in the two groups (69% vs 62%; p=0.57 and between patients with paroxysmal atrial fibrillation (68% vs 68%; p=0.91) or persistent AF (75% vs 48%; p=0.60). AF duration before the ablation procedure (p=0.005) was an independent predictor of AF recurrence. Phrenic nerve palsy rate was not statistically different in the two groups (4 [14%] vs 9 [10%]; p=0.73). The temperature in the right superior pulmonary vein (p=0.008) was an independent predictor of phrenic nerve palsy. Five patients developed left atrial flutter with the 28mm diameter balloon versus none with the 23mm balloon. CONCLUSIONS: A dual balloon size strategy was not associated with a lower AF-free survival or a higher procedure-related complication rate in patients in whom the 23mm balloon was used. Pulmonary vein isolation with a 23mm cryoballoon catheter appears to be an appropriate option in selected patients with small pulmonary vein diameters.


Assuntos
Fibrilação Atrial/cirurgia , Criocirurgia/instrumentação , Veias Pulmonares/cirurgia , Idoso , Fibrilação Atrial/fisiopatologia , Distribuição de Qui-Quadrado , Criocirurgia/efeitos adversos , Intervalo Livre de Doença , Desenho de Equipamento , Feminino , França , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Nervo Frênico/lesões , Modelos de Riscos Proporcionais , Estudos Prospectivos , Veias Pulmonares/fisiopatologia , Recidiva , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
17.
Arch Cardiovasc Dis ; 103(11-12): 570-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21147441

RESUMO

BACKGROUND: Ajmaline challenge is commonly used for the diagnosis of Brugada syndrome. A slow infusion rate has been recommended in view of the proarrhythmic risk, but the diagnostic value of various infusion rates has not been investigated. AIMS: To compare rapid and slow ajmaline infusion rates and to assess the proarrhythmic risk. METHODS: The first part of this study prospectively compared rapid and slow infusion rates in terms of results and ventricular arrhythmias. Thirty-two patients (mean age 41±12 years; 26 men) received the two ajmaline challenges on different days. According to randomization, ajmaline (1 mg/kg) was infused at 1 mg/sec or over 10 minutes. The second part of the study retrospectively assessed the prevalence of ventricular arrhythmia during 386 challenges performed at a rapid infusion rate. RESULTS: No differences were observed between rapid and slow tests. All patients diagnosed as positive or negative with one test obtained the same result with the other test. Ventricular premature beats were observed in five of 32 patients during the slow challenge and in four of 32 patients during the rapid challenge. No sustained ventricular arrhythmias were observed. Analysis of the 386 tests revealed four episodes of ventricular arrhythmia (two complex ventricular premature beats, one non-sustained ventricular tachycardia and one ventricular fibrillation). CONCLUSION: Slow and rapid infusions of ajmaline have identical diagnostic performances on suspected Brugada electrocardiograms. Owing to the risk of severe proarrhythmia, a slow infusion rate, allowing early discontinuation, should be recommended.


Assuntos
Ajmalina , Síndrome de Brugada/diagnóstico , Eletrocardiografia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ajmalina/administração & dosagem , Ajmalina/efeitos adversos , Estudos Cross-Over , Feminino , França , Humanos , Infusões Parenterais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Estudos Retrospectivos , Taquicardia Ventricular/induzido quimicamente , Fatores de Tempo , Fibrilação Ventricular/induzido quimicamente , Complexos Ventriculares Prematuros/induzido quimicamente , Adulto Jovem
18.
Am J Cardiol ; 106(12): 1758-62, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21126620

RESUMO

The familial prevalence of Brugada syndrome (BrS) in a consecutive series of patients was prospectively determined. BrS is genetically determined with autosomal dominant transmission. The familial prevalence of the BrS is unknown. A detailed pedigree of each family of patients with BrS was assembled and permission was obtained to invite relatives for electrocardiography and an ajmaline challenge. Sixty-two of 98 patients participated in the study and were included over a 6-year period. SCN5A genotyping was performed in 56 of these 62 patients (90%). Electrocardiograms (ECGs) of 488 relatives (mean age 38 ± 20 years, 45% men) were recorded and 270 of these relatives agreed to undergo an ajmaline challenge. Spontaneous type 1 BrS ECG was found in 4 of 488 relatives (0.8%). In the group of relatives in whom ajmaline challenge was performed (n = 270), the finding was positive in 79 subjects (29%). SCN5A genotyping identified 5 other affected relatives. As a result, the total number of affected relatives was 88. Standard 12-lead ECG was normal in 64 of the 88 affected relatives (73%). Mean percentage of affected relatives per family was 27 ± 32% (95% confidence interval 19 to 35). Familial forms of BrS were observed in 41 of the 62 families (66%) and no SCN5A mutations were found in sporadic forms. In conclusion, after active family screening affected relatives were found in almost 1/3 of subjects. BrS appeared to be a familial disease in 2/3 of subjects.


Assuntos
Síndrome de Brugada/genética , DNA/genética , Proteínas Musculares/genética , Mutação , Canais de Sódio/genética , Adulto , Síndrome de Brugada/diagnóstico , Síndrome de Brugada/epidemiologia , Eletrocardiografia , Feminino , Seguimentos , França/epidemiologia , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Canal de Sódio Disparado por Voltagem NAV1.5 , Linhagem , Reação em Cadeia da Polimerase , Estudos Prospectivos
20.
Int J Cardiol ; 135(2): 266-9, 2009 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-18619692

RESUMO

Thirty-three consecutive patients with aortic stenosis underwent a 16-row spiral CT scan. Aortic valve planimetry was performed using two methods: double-oblique reformation (DO) and 2D-curved multiplanar reconstruction using advanced vessel analysis software (VA). The mean aortic valve area determined by transthoracic echocardiography was 0.88+/-0.34 [0.53-1.88] and did not differ significantly from that determined by CT (DO): 0.87+/-0.38 [0.42-1.93] (p=0.75) or CT (VA): 0.87+/-0.38 [0.44-2.00] (p=0.69). This study demonstrates that 16-row spiral CT scan is a feasible, accurate and reproducible method for aortic valve planimetry in patients with aortic stenosis. Both methods show similar accuracy but the VA method takes slightly longer.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Valva Aórtica/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada Espiral/métodos , Idoso , Idoso de 80 Anos ou mais , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/normas , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Tomografia Computadorizada Espiral/normas
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