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1.
Int J Obes (Lond) ; 39(8): 1236-40, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25835554

RESUMO

BACKGROUND AND OBJECTIVES: Oxidative stress and the insulin-resistant state are thought to be key components in the pathogenesis of pediatric nonalcoholic fatty liver disease (NAFLD). Heme oxygenase (HO) is important in the defense against oxidative stress. This study aimed to assess the association of HO-1 gene promoter polymorphism and insulin resistance with NAFLD among obese children. METHODS: A total of 101 obese children aged 6-17 years were recruited. Anthropometric, serum biochemical variables and biomarkers for glucose and insulin metabolism were measured. We screened the allelic frequencies of (GT)n repeats in the HO-1 gene promoter among these obese children. NAFLD was determined through liver ultrasonography. Because the distribution of numbers of (GT)n repeats was bimodal, we divided the alleles into two classes: class S included shorter (27) repeats, and class L included longer (⩾27) repeats. We assessed the effects of the length of (GT)n repeats in HO-1 gene promoter on pediatric NAFLD. RESULTS: Of the 101 obese subjects, 27 (26.7%) had NAFLD. The alanine aminotransferase level was higher in patients carrying L alleles (L/L and L/S) than patients with S alleles (S/S) (46.2±49.3 IU|(-1) versus 30.2±20.1 IU|(-1); P=0.027). The significant risk factors for pediatric NAFLD were patients carrying L alleles (L/L and L/S) (odds ratio (OR)=18.84; 95% confidence interval (CI): 1.45-245.22; P=0.025), homeostasis model assessment of insulin resistance (OR=1.40; 95% CI: 1.07-1.83; P=0.014) and age (OR=1.24; 95% CI: 1.03-1.50; P=0.025). CONCLUSION: In this hospital-based study, the obese children with longer GT repeats in the HO-1 gene promoter and insulin resistance were susceptible to NAFLD.


Assuntos
Predisposição Genética para Doença/genética , Heme Oxigenase-1/genética , Hepatopatia Gordurosa não Alcoólica/etiologia , Estresse Oxidativo/genética , Obesidade Infantil/complicações , Adolescente , Criança , Feminino , Humanos , Resistência à Insulina , Masculino , Repetições de Microssatélites , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/genética , Obesidade Infantil/epidemiologia , Obesidade Infantil/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Fatores de Risco , Taiwan/epidemiologia
2.
Eur J Neurol ; 21(10): 1285-91, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24909847

RESUMO

BACKGROUND AND PURPOSE: Orolingual angioedema (OA) is an uncommon but potentially life-threatening complication of treatment with recombinant tissue plasminogen activator (rt-PA; alteplase) during acute ischaemic stroke. This study aimed to determine the incidence of rt-PA-related OA in an Asian stroke population and the risk of pre-stroke anti-hypertensive drug use for development of this complication. METHODS: A multi-center stroke registry was used to identify the pre-stroke medications of acute ischaemic stroke patients receiving intravenous rt-PA from January 2002 to December 2013. The clinical manifestations of rt-PA-related OA were recorded and the incidence of this complication was determined. The risks of pre-stroke use of different anti-hypertensive agents for the occurrence of rt-PA-related OA were determined from this study and from a meta-analysis. RESULTS: A total of 559 patients received intravenous rt-PA over a 12-year period. Five patients (two males) developed OA after rt-PA administration. The incidence of OA amongst these patients was 0.89% (95% confidence interval 0.29%-2.09%), which was lower than that obtained by meta-analysis (1.9%). Amongst pre-stroke anti-hypertensive medications, angiotensin-converting enzyme (ACE) inhibitors were found in this study to have the highest relative risk for rt-PA-related OA (17.1; 95% confidence interval 3.0-96.9). Meta-analysis also revealed that pre-stroke use of ACE inhibitors was associated with a high relative risk of OA after intravenous rt-PA (12.9; 95% confidence interval 4.5-37.0). CONCLUSIONS: The incidence of rt-PA-related OA in the Asian population is lower than that in the Caucasian population. Pre-stroke use of ACE inhibitors significantly increases the risk of this complication.


Assuntos
Angioedema/induzido quimicamente , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/efeitos adversos , Doenças da Boca/induzido quimicamente , Sistema de Registros/estatística & dados numéricos , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/efeitos adversos , Ativador de Plasminogênio Tecidual/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Angioedema/epidemiologia , Isquemia Encefálica/epidemiologia , Feminino , Fibrinolíticos/administração & dosagem , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Doenças da Boca/epidemiologia , Risco , Acidente Vascular Cerebral/epidemiologia , Taiwan/epidemiologia , Terapia Trombolítica/estatística & dados numéricos , Ativador de Plasminogênio Tecidual/administração & dosagem , Ativador de Plasminogênio Tecidual/uso terapêutico , Doenças da Língua/induzido quimicamente , Doenças da Língua/epidemiologia
3.
Eur J Neurol ; 20(8): 1128-34, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22897602

RESUMO

BACKGROUND AND PURPOSE: Anticoagulant and antiplatelets for prevention of ischaemic stroke and cardiovascular diseases may increase the risk of intracerebral hemorrhage (ICH). This study aimed to investigate the influence of pre-ICH use of anticoagulant and antiplatelets on ICH patients. METHODS: Consecutive patients with acute spontaneous ICH registered in a single-center stroke registry during 2001 to 2010 were analyzed and categorized according to their pre-ICH use of warfarin (Group I), antiplatelets (Group II), or neither (Group III). Survival analysis and the Cox proportional hazard model were used to compare between the three groups and the predictors. RESULTS: Of 2021 ICH patients (male, 63.3%; mean age, 62.6 ± 14.4 years) included, there were 94 (4.7%) in Group I, 232 (11.4%) in Group II, and 1695 (83.9%) in Group III. Warfarin users had larger hematoma volume, more intraventricular extension, higher frequencies of lobar ICH, and higher case fatality than non-warfarin users (Groups II and III). The Cox proportional hazard model showed increased 6-month case fatality in pre-ICH warfarin users (adjusted hazard ratio 2.75, 95% confidence interval 2.04-3.72, P < 0.001), but not in pre-ICH antiplatelet users (adjusted hazard ratio 0.95, 95% confidence interval 0.72-1.26). CONCLUSIONS: Intracerebral hemorrhage patients with prior warfarin use, but not antiplatelet use, had significantly higher case fatality at 6 months.


Assuntos
Anticoagulantes/efeitos adversos , Hemorragia Cerebral/mortalidade , Inibidores da Agregação Plaquetária/efeitos adversos , Varfarina/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Hemorragia Cerebral/patologia , Feminino , Escala de Coma de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Curva ROC , Sistema de Registros , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Análise de Sobrevida , Taiwan/epidemiologia
4.
J Neurol Neurosurg Psychiatry ; 80(11): 1225-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19332420

RESUMO

OBJECTIVES: Early diagnosis and management of intracranial dural arteriovenous fistulae (DAVF) may prevent the occurrence of stroke. This study aimed to identify the best carotid duplex sonography (CDS) parameters for screening DAVF. METHODS: 63 DAVF patients and 170 non-DAVF patients received both CDS and conventional angiography. The use of seven CDS haemodynamic parameter sets related to the resistance index (RI) of the external carotid artery (ECA) for the diagnosis of DAVF was validated and the applicability of the best CDS parameter set in 20 400 patients was tested. RESULTS: The CDS parameter set (ECA RI (cut-off point = 0.7) and internal carotid artery (ICA) to ECA RI ratio (cut-off point = 0.9)) had the highest specificity (99%) for diagnosis of DAVF with moderate sensitivity (51%). Location of the DAVF was a significant determinant of sensitivity of detection, which was 70% for non-cavernous DAVF and 0% for cavernous sinus DAVF (p<0.001). The above parameter set detected abnormality in 92 of 20 400 patients. These abnormalities included DAVF (n = 25), carotid stenosis (n = 32), vertebral artery stenosis (n = 7), intracranial arterial stenosis (n = 6), head and neck tumour (n = 3) and unknown aetiology (n = 19). CONCLUSION: Combined CDS parameters of ECA RI and ICA to ECA RI ratio can be used as a screening tool for the diagnosis of DAVF.


Assuntos
Artéria Carótida Externa/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/diagnóstico , Ultrassonografia Doppler Dupla/métodos , Adulto , Angiografia , Artéria Carótida Externa/patologia , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
5.
J Med Eng Technol ; 27(2): 77-84, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12745915

RESUMO

During the last decade, progressive achievements in haemodynamics have shown that radial artery pulse pressure can be used to estimate the vascular properties of the internal organs. Clinical experiments have shown that slow and regular respiration has a large effect on the heart rate variability (HRV). This phenomenon is called respiratory sinus arrhythmia (RSA). It is known that respiration-related oscillations in venous return cause oscillations in stroke volume and blood pressure. It also can be inferred from cardiac output that systemic blood pressure has a similar respiration-related cycle. Moreover we found that the fluctuations of harmonics of arterial pulse are consistent with the fluctuation of HRV. This means that the whole cardiovascular system (CVS) makes rapid adaptation during respiration, and the harmonic proportions of arterial pulse were modified during different breath rates. This result shows that the regular respiration also has a large effect upon Windkessel properties of CVS.


Assuntos
Pulso Arterial , Respiração , Adulto , Pressão Sanguínea , Frequência Cardíaca , Humanos , Masculino , Artéria Radial
6.
Comput Biol Med ; 31(6): 471-80, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11604152

RESUMO

Time domain cross-correlation analysis of pre-filtered mean arterial blood pressure (MABP) and mean cerebral blood flow velocity (MCBFV) was applied to assess the cerebral autoregulation (CA). Beat-to-beat time series of spontaneous arterial blood pressure and cerebral blood flow velocity were obtained from 13 young normal volunteers with the Finapres device and the transcranial Doppler for periods of approximately 5 min in the supine position. Cross-correlation functions (CCFs) were estimated using a 64 beat wide moving window. Mean CCF patterns were obtained for each subject and for the entire population. The MABP and MCBFV signals were bandpass filtered in the very low-frequency range (VLF, 0.015-0.07 Hz), low-frequency range (LF, 0.07-0.15 Hz) and high-frequency range (HF, 0.15-0.40 Hz) before applying CCF for the purpose of studying the effect of different bandwidths on the resulting mean CCFs. Results revealed that the corresponding time lags of the peak values of the MABP-MCBFV CCFs increased significantly between the LF and HF frequency ranges (LF: -1.20+/-0.91 s, HF: -0.07+/-0.42 s,p < 0.001; paired sign test). The left-shift (negative lag) of the CCF peak between MABP and MCBFV is a result of the phase-lead property. The increasing time lag of the CCF peak indicated evidence of the autoregulatory disturbance. The CCF of pre-filtered spontaneous MABP and MCBFV could be a useful tool to estimate the CA dynamic response.


Assuntos
Circulação Cerebrovascular/fisiologia , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Computadores , Feminino , Homeostase , Humanos , Masculino , Modelos Cardiovasculares , Processamento de Sinais Assistido por Computador , Ultrassonografia Doppler Transcraniana
7.
Med Pediatr Oncol ; 35(6): 716-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11107154

RESUMO

BACKGROUND: Intrathecal antibody-based targeted therapies may have clinical potential for patients with leptomeningeal (LM) cancer. PROCEDURE: Five patients with GD2-positive LM tumors were injected with 1-2 mCi intra-Ommaya (131)I-3F8, a murine IgG3 antibody specific for GD2. Serial cerebrospinal fluid (CSF) and serum samples and SPECT imagings (4, 24, and 48 hr) were performed to predict radiation doses to the tumor and normal brain and blood prior to the administration of larger therapeutic doses. RESULTS: Side effects included self-limited fever, headache, and vomiting. Focal (131)I-3F8 uptake consistent with tumors was seen along the craniospinal axis in four patients. Calculated radiation dose to the CSF was 14.9-56 cGy/mCi and to blood and other organs outside the CNS less than 2 cGy/mCi. CONCLUSIONS: Intraventricular (131)I-3F8 successfully detected LM disease and resulted in a large favorable CSF/blood ratio. Intraventricular (131)I-3F8 may have clinical utility in the diagnosis and radioimmunotherapy of GD2-positive LM cancers. Med. Pediatr. Oncol. 35:716-718. 2000.


Assuntos
Anticorpos Monoclonais , Anticorpos/uso terapêutico , Imunoglobulina G , Imunoglobulinas/uso terapêutico , Radioisótopos do Iodo/uso terapêutico , Neoplasias Meníngeas/radioterapia , Radioimunoterapia , Anticorpos Monoclonais Murinos , Criança , Pré-Escolar , Humanos , Lactente , Pessoa de Meia-Idade
8.
Chem Pharm Bull (Tokyo) ; 48(2): 288-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10705522

RESUMO

An efficient one-pot procedure for the preparation of diazadioxime was described. Treatment of ketooximes with alkyldiamine followed by NaBH4 in dry ethanol afforded the corresponding d,l-diazadioximes in 56--74% yield without isolation of the intermediates.


Assuntos
Diaminas/síntese química , Oximas/síntese química , Compostos Radiofarmacêuticos/síntese química , Indicadores e Reagentes , Ligantes , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho
9.
Comput Biol Med ; 30(2): 71-88, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10714443

RESUMO

A self-organizing classification system for the arterial pressure pulse based on the ART2 (adaptive resonance theory) network was developed. The system consists of a preprocessor and an ART2 recognition network. The preprocessor removes the arterial pressure pulse servo component signals from Finapres, detects the systolic pressure points and divides the acquired signals into minimal cardiac cycles. The ART2 network input is the minimal cardiac cycle detected by the preprocessor. The classification results can be used to assist physicians in evaluating the signs of abnormal and normal autonomic control and has shown its clinical applicability for the examination of the autonomic nervous system.


Assuntos
Modelos Cardiovasculares , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão , Pulso Arterial/classificação , Artefatos , Diabetes Mellitus Tipo 2/fisiopatologia , Humanos , Fotopletismografia/instrumentação , Postura , Valores de Referência
10.
Catheter Cardiovasc Interv ; 49(1): 91-6, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10627378

RESUMO

Tissue plasminogen activator (t-PA) was administered to three patients with newly developed intracardiac thrombi. Cases 1 and 2 developed right heart thrombi after radiofrequency ablation for atrioventricular nodal reentrant tachycardia and case 3 had tachycardia-related cardiomyopathy and a left ventricular thrombus. In all three patients, the intracardiac thrombi were successfully eliminated following t-PA therapy without major bleeding complications. These observations suggest that t-PA is effective in lysing new thrombus complicating radiofrequency ablation or heart failure and may be the therapy of choice in these conditions. Cathet. Cardiovasc. Intervent. 49:91-96, 2000.


Assuntos
Fibrinolíticos/uso terapêutico , Cardiopatias/tratamento farmacológico , Terapia Trombolítica , Trombose/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Adulto , Idoso , Feminino , Cardiopatias/diagnóstico por imagem , Cardiopatias/etiologia , Humanos , Masculino , Trombose/diagnóstico por imagem , Trombose/etiologia , Ultrassonografia
11.
Bioorg Med Chem Lett ; 9(22): 3199-202, 1999 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-10576687

RESUMO

Tc-D,D- and TC-L,L-HMPAO were synthesized. The stability of Tc-D,D- and TC-L,L-HMPAO in vitro is similar to that of d,l-isomers by the spectrophotometric and three strips methods. Cerebral uptake (%D in brain) for the L,L-isomer is higer than the D,D- and d,l-isomer in rats. Delayed studies shows that T-L,L-HMPAO reveals less washout and reflects a higher cerebral deposition properties than the D,D- and d,l-isomer.


Assuntos
Tecnécio Tc 99m Exametazima/síntese química , Animais , Feminino , Isomerismo , Ratos , Ratos Wistar , Tecnécio Tc 99m Exametazima/química , Tecnécio Tc 99m Exametazima/farmacologia
12.
J Am Coll Cardiol ; 33(2): 376-84, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9973017

RESUMO

OBJECTIVES: The main objective of this study was to characterize the phenomenon of variation in the P-QRS relation during atrioventricular node reentry tachycardia. BACKGROUND: Variation of P-QRS relation during tachycardia has been observed occasionally in atrioventricular node reentry tachycardia. However, the incidence, the characteristics and the mechanisms of this phenomenon have not been investigated previously. METHODS: Retrospective analysis was performed in 311 consecutive patients with slow-fast form and 108 patients with atypical or multiple form of atrioventricular node reentry tachycardia to examine whether variation of P-QRS relation with changes in AH, HA and AH/HA (A = atria; H = His bundle) ratio occurred during tachycardia. RESULTS: A total of 28 patients, 8 with slow-fast and 20 with atypical or multiple tachycardias, were found to manifest this phenomenon. There were 6 males and 22 females, with an average age of 38+/-16 years. In 10 patients, this phenomenon occurred transiently following electrical induction of the tachycardia. In 15 patients, changes in AH, HA and AH/HA ratio were associated with the occurrence of Wenckebach or 2:1 block proximal to the His bundle (H) recording site without interruption of the tachycardia. In nine patients, three with nonsustained tachycardia and six after administration of adenosine triphosphate, this phenomenon was observed at the termination of the tachycardia. This phenomenon was usually accompanied by a mild lengthening of the tachycardia cycle length. CONCLUSIONS: Variation of P-QRS relation with or without block may occur during atrioventricular node reentry tachycardia, especially in atypical or multiple-form tachycardias. It was postulated that decremental conduction in the distal common pathway, which exists between the distal link of the reentry circuit and the H, is primarily responsible for this phenomenon.


Assuntos
Eletrocardiografia , Frequência Cardíaca , Taquicardia por Reentrada no Nó Atrioventricular/fisiopatologia , Trifosfato de Adenosina/administração & dosagem , Trifosfato de Adenosina/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Nó Atrioventricular/fisiopatologia , Fascículo Atrioventricular/fisiopatologia , Estimulação Cardíaca Artificial , Criança , Feminino , Seguimentos , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taquicardia por Reentrada no Nó Atrioventricular/terapia
13.
J Clin Oncol ; 16(9): 3053-60, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9738575

RESUMO

PURPOSE: To eradicate minimal residual disease with anti-G(D2) monoclonal antibody 3F8 in stage 4 neuroblastoma (NB) diagnosed at more than 1 year of age. PATIENTS AND METHODS: Thirty-four patients were treated with 3F8 at the end of chemotherapy. Most had either bone marrow (n=31) or distant bony metastases (n=29). Thirteen patients were treated at second or subsequent remission (group I) and 12 patients in this group had a history of progressive/persistent disease after bone marrow transplantation (BMT); 21 patients were treated in first remission following N6 chemotherapy (group II). RESULTS: Before 3F8 treatment, 23 patients were in complete remission CR, eight in very good partial remission (VGPR), one in partial remission (PR), and two had microscopic foci in marrow. Twenty-five had evidence of NB by at least one measurement of occult/minimal tumor (iodine 131[(131)I]-3F8 imaging, marrow immunocytology, or marrow reverse-transcriptase polymerase chain reaction [RT-PCR]). Acute self-limited toxicities of 3F8 treatment were severe pain, fever, urticaria, and reversible decreases in blood counts and serum complement levels. There was evidence of response by immunocytology (six of nine), by GAGE RT-PCR (seven of 12), and by (131)I-3F8 scans (six of six). Fourteen patients are alive and 13 (age 1.8 to 7.4 years at diagnosis) are progression-free (40 to 130 months from the initiation of 3F8 treatment) without further systemic therapy, none with late neurologic complications. A transient anti-mouse response or the completion of four 3F8 cycles was associated with significantly better survival. CONCLUSION: Despite high-risk nature of stage 4 NB, long-term remission without autologous (A)BMT can be achieved with 3F8 treatment. Its side effects were short-lived and manageable. The potential benefits of 3F8 in consolidating remission warrant further investigations.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Gangliosídeos/imunologia , Neoplasia Residual/terapia , Neuroblastoma/terapia , Anticorpos Monoclonais/efeitos adversos , Antígenos de Neoplasias/biossíntese , Neoplasias da Medula Óssea/secundário , Neoplasias Ósseas/secundário , Criança , Pré-Escolar , Terapia Combinada , Feminino , Humanos , Imunoterapia , Lactente , Masculino , Estadiamento de Neoplasias , Neuroblastoma/tratamento farmacológico , Neuroblastoma/radioterapia , Resultado do Tratamento
14.
J Am Soc Echocardiogr ; 11(6): 668-72, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9657407

RESUMO

Anomalous origin of the left coronary artery from the pulmonary artery in adults is difficult to identify reliably by transthoracic echocardiography (TTE). We describe a 32-year-old woman with this coronary anomaly mimicking a coronary artery fistula on conventional TTE study. This anomaly was suggested by multiplane transesophageal echocardiography (TEE) and subsequently confirmed by coronary angiography. Multiplane TEE thus may serve as a first-line diagnostic tool for detecting anomalous origin of coronary arteries.


Assuntos
Anomalias dos Vasos Coronários/diagnóstico por imagem , Ecocardiografia Transesofagiana/métodos , Artéria Pulmonar/anormalidades , Adulto , Feminino , Humanos
15.
Am J Cardiol ; 81(4): 500-3, 1998 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9485145

RESUMO

Clinical and electrophysiologic parameters were analyzed to define the factors potentially related to tachycardia recurrences in 79 patients undergoing successful radiofrequency ablation of idiopathic right or left ventricular tachycardia. It was found that the endocardial activation time at the successful ablation site was the only independent predictor of tachycardia recurrences.


Assuntos
Ablação por Cateter , Taquicardia Ventricular/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Eletrocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Taquicardia Ventricular/fisiopatologia , Falha de Tratamento
16.
J Cardiovasc Electrophysiol ; 8(11): 1302-8, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9395174

RESUMO

INTRODUCTION: Fast-intermediate form AV nodal reentry tachycardia (AVNRT) sometimes may mimic atrial tachycardia or atrial flutter and render the diagnosis difficult when the tachycardia rate is fast and AV block occurs during tachycardia. METHODS AND RESULTS: A 45-year-old woman with paroxysmal supraventricular tachycardia was referred to this institution. Initially, the tachycardia was thought to be an atrial tachycardia because of: (1) a short cycle length of the tachycardia with 2:1 and Wenckebach AV block; (2) a difference in the atrial activation sequence during tachycardia and during ventricular pacing; and (3) failure of burst ventricular pacing to affect the atrial rate and the atrial activation sequence during tachycardia. An accurate diagnosis of fast-intermediate form AVNRT was subsequently made based on the finding that the tachycardia was induced following delivery of a third ventricular extrastimulus, which showed a sequence of V-A-H and a change on atrial activation sequence of the induced beat. Successful radiofrequency ablation was achieved only after accurate diagnosis of the tachycardia was made. CONCLUSION: Fast-intermediate form AVNRT sometimes may masquerade as atrial tachycardia. Accurate diagnosis is mandatory for successful ablation therapy.


Assuntos
Ablação por Cateter , Taquicardia por Reentrada no Nó Atrioventricular/fisiopatologia , Taquicardia/fisiopatologia , Eletrocardiografia , Feminino , Humanos , Pessoa de Meia-Idade , Taquicardia/cirurgia , Taquicardia por Reentrada no Nó Atrioventricular/cirurgia
17.
J Am Coll Cardiol ; 30(5): 1339-45, 1997 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9350937

RESUMO

OBJECTIVES: This study demonstrates that exercise-provocable tachycardia resembling right ventricular outflow tract tachycardia may originate from the anterobasal left ventricle. BACKGROUND: Reentry is the operative mechanism of idiopathic left ventricular tachycardia, with a QRS complex of right bundle branch block and superior axis that is responsive to verapamil but not adenosine. Whether some mechanism other than reentry is operative in some idiopathic left ventricular tachycardias is unclear. METHODS: In 4 of 53 consecutive patients with idiopathic left ventricular tachycardia, the tachycardia was sensitive to adenosine. These four patients were women 63, 61, 61 and 31 years old and were the subjects of the present study. RESULTS: In all four patients, spontaneous tachycardia was related to exercise or emotional stress. The tachycardia displayed atypical left (one patient) or right (three patients) bundle branch block with an inferior axis and marked variation in cycle length. An intravenous bolus of adenosine triphosphate (10 to 20 mg) terminated tachycardia in all four patients. Tachycardia was terminated or prevented in three patients given intravenous or oral verapamil. Atrial or ventricular incremental or extrastimulus testing induced tachycardia in all four patients (three with, one without isoproterenol infusion). Electrically induced tachycardia also demonstrated marked variation in cycle length, which ranged from 230 to 390 ms. Entrainment was not demonstrable with overdrive pacing from multiple sites. Endocardial mapping during tachycardia revealed that the earliest activations were registered 25, 40, 35 and 50 ms before onset of the QRS complex, respectively, from the anterior aspect of the left ventricle just below the mitral annulus, adjacent to the left ventricular outflow tract. High frequency Purkinje spikes were not recorded at this site. Radiofrequency current delivered to this site successfully ablated the tachycardia in three of the four patients. CONCLUSIONS: Exercise-provocable, catecholamine-mediated, verapamil-responsive, adenosine-sensitive ventricular tachycardia may arise from the anterobasal left ventricle adjacent to the outflow tract.


Assuntos
Taquicardia Ventricular/fisiopatologia , Adenosina/uso terapêutico , Adulto , Antiarrítmicos/uso terapêutico , Eletrocardiografia , Eletrofisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Taquicardia Ventricular/tratamento farmacológico
18.
J Am Coll Cardiol ; 30(4): 1024-31, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9316534

RESUMO

OBJECTIVES: This study sought to assess the possibility of ablating verapamil-responsive idiopathic left ventricular tachycardia at a site distant from the tachycardia exit and thus to define the tachycardia circuit. BACKGROUND: The nature of the reentry circuit in idiopathic left ventricular tachycardia is unclear. If the circuit is of considerable size, then it should be possible to ablate the tachycardia at a site distant from the exit site. METHODS: Electrophysiologic studies and radiofrequency ablation were performed in 27 consecutive patients with verapamil-responsive idiopathic left ventricular tachycardia. In all 27 patients, the tachycardia exit site was defined as the site where the earliest Purkinje potential was recorded > or = 25 ms before the onset of the QRS complex during the tachycardia and where the pace map QRS complex resembled that during the tachycardia. A potential ablation site other than the exit site was then sought around the midseptum, proximal to the exit site. At such sites the tachycardia could be terminated transiently by pressure applied to the catheter tip, without induction of ventricular ectopic beats. RESULTS: The potential ablation site, other than the tachycardia exit site, was identified in seven male patients (mean [+/-SD] age 31 +/- 12 years, range 13 to 52). Application of the radiofrequency current at this site resulted in termination of the tachycardia within 1 to 5 s (mean 2.9 +/- 1.6), and successful ablation of the tachycardia was achieved in all seven patients (success rate 100%, 95% exact confidence interval 0.5898 to 1). The mean distance between the ablation site and the tachycardia exit site was 3.1 +/- 0.7 cm (range 2.0 to 4.0). A presystolic Purkinje spike was recorded 14 +/- 5 ms (range 8 to 20) before the onset of the QRS complex during the tachycardia. During the follow-up period of 24 +/- 11 months (range 12 to 39), there was no recurrence of tachycardia in these seven patients. CONCLUSIONS: Successful ablation of idiopathic left ventricular tachycardia can be achieved at sites away from the tachycardia exit site in some patients. This finding suggests that the reentry circuit is likely to be of considerable size, encompassing the middle, inferior and lower aspects of the left interventricular septum.


Assuntos
Ablação por Cateter/métodos , Sistema de Condução Cardíaco/fisiopatologia , Sistema de Condução Cardíaco/cirurgia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/cirurgia , Potenciais de Ação , Adolescente , Adulto , Ablação por Cateter/normas , Eletrocardiografia , Feminino , Seguimentos , Sistema de Condução Cardíaco/patologia , Septos Cardíacos/patologia , Ventrículos do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Taquicardia Ventricular/patologia , Resultado do Tratamento
19.
Cathet Cardiovasc Diagn ; 42(1): 70-2, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9286547

RESUMO

This report describes a patient who developed stenosis of coronary sinus and cardiac veins five years after application of electric shock currents to the posterior mitral annulus and posteroseptal region of the tricuspid annulus for ablation of a left posterior accessory pathway and a right posteroseptal accessory pathway. This is the first angiographic documentation of coronary sinus stenosis as a late complication of electric ablation of accessory pathway.


Assuntos
Ablação por Cateter , Doença das Coronárias/etiologia , Complicações Pós-Operatórias , Síndrome de Wolff-Parkinson-White/cirurgia , Adulto , Constrição Patológica , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Sistema de Condução Cardíaco/anormalidades , Sistema de Condução Cardíaco/cirurgia , Humanos , Masculino
20.
Eur J Nucl Med ; 24(6): 590-5, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9169563

RESUMO

The search for an ideal radioisotope for systemic radiotherapy continues. As a generator-produced radioisotope emitting both beta and gamma rays and having a short physical half-life of 16.9 h, rhenium-188 is a very good potential candidate for systemic radiotherapy. In this study, we labeled hydroxyethylidene diphosphonate (HEDP) with 188Re and analyzed the biodistribution and bone uptake following intravenous injection in rats to assess its potential for clinical use. The rats were injected with approximately 14.8 MBq (0.4 mCi) 188Re-HEDP in a volume of 0.1 ml intravenously and then sacrificed at 1 h, 24 h, or 48 h (four rats at each time). Samples (about 0.1 g) of lung, liver, kidney, spleen, testis, muscle, stool, and bone (thoracic vertebra) were taken and weighed carefully. In addition, a 1-ml sample of blood was drawn from the heart and 1 ml of urine was taken from the urinary bladder immediately after killing. Tissue concentrations were calculated and expressed as percent injected dose per gram or per milliliter (% ID/g or ml). Bone lesions were created in the right tibial bone in three rabbits to calculate the lesion to normal uptake ratio (L/N ratio). The biodistribution data showed that the radioactivity in the bone tissue was as high as 1.877% ID/g at 1 h and that it climbed to 2.017% ID/g at 4 h. The activity level in the kidney was highest at 1 h but declined rapidly throughout the study. The radioactivities in the lung, liver, muscle, spleen, testis, blood, and stool were all lower than 0.3% ID/g at 1 h and also declined rapidly. The biological half-life in bone was the longest (60.86 h). In contrast, the biological half-lives in muscle and blood were short (2.99 h and 6.21 h respectively). The concentrations of radioactivity in muscle, spleen, testis, and stool were quite low throughout the study. Most of the radiotracer was excreted by the urinary system. The L/N ratio was 4.23+/-0.21 in rabbits injected with 188Re-HEDP and 4.25+/-0.23 in those injected with technetium-99m methylene diphosphonate. In conclusion, we would suggest that 188Re-HEDP is a very good potential candidate for the treatment of bone metastases because of the following characteristics: (1) it is generator produced; (2) it has a short half-life; (3) it emits gamma rays suitable for imaging; (4) there is highly selective uptake in the skeletal system and bone lesions; and (5) it has a low non-target uptake and rapid clearance in nonosseous tissue.


Assuntos
Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Ácido Etidrônico/uso terapêutico , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Rênio/uso terapêutico , Animais , Ácido Etidrônico/farmacocinética , Meia-Vida , Humanos , Masculino , Coelhos , Doses de Radiação , Radioisótopos/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Ratos , Ratos Sprague-Dawley , Rênio/farmacocinética , Distribuição Tecidual
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