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1.
Pacing Clin Electrophysiol ; 40(2): 162-174, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28000227

RESUMO

BACKGROUND: The role of J-waves in the pathogenesis of ventricular fibrillation (VF) occurring in structurally normal hearts is important. METHODS: We evaluated 127 patients who received an implantable cardioverter-defibrillator (ICD) for Brugada syndrome (BS, n = 53), early repolarization syndrome (ERS, n = 24), and patients with unknown or deferred diagnosis (n = 50). Electrocardiography (ECG), clinical characteristics, and ICD data were analyzed. RESULTS: J-waves were found in 27/50 patients with VF of unknown/deferred diagnosis. The J-waves were reminiscent of those seen in BS or ERS, and this subgroup of patients was termed variants of ERS and BS (VEB). In 12 VEB patients, the J/ST/T-wave morphology was coved, although amplitudes were <0.2 mV. In 15 patients, noncoved-type J/ST/T-waves were present in the right precordial leads. In the remaining 23 patients, no J-waves were identified. VEB patients exhibited clinical characteristics similar to those of BS and ERS patients. Phenotypic transition and overlap were observed among patients with BS, ERS, and VEB. Twelve patients with BS had background inferolateral ER, while five ERS patients showed prominent right precordial J-waves. Patients with this transient phenotype overlap showed a significantly lower shock-free survival than the rest of the study patients. CONCLUSIONS: VEB patients demonstrate ECG phenotype similar to but distinct from those of BS and ERS. The spectral nature of J-wave morphology/distribution and phenotypic transition/overlap suggest a common pathophysiologic background in patients with VEB, BS, and ERS. Prognostic implication of these ECG variations requires further investigation.


Assuntos
Síndrome de Brugada/classificação , Síndrome de Brugada/diagnóstico , Eletrocardiografia/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/classificação , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
Heart Rhythm ; 20(12): 1639-1646, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37543304

RESUMO

BACKGROUND: Evidence of the long-term outcomes of abandoned leads (ALs) in patients with cardiac implantable electronic devices (CIEDs) is scarce. OBJECTIVE: This study aimed to investigate the long-term outcomes of ALs. METHODS: This retrospective cohort study reviewed a single-center CIED registry of 2962 procedures performed from 1984-2018 and identified 130 patients with AL (AL group). We matched 2 controls without AL (by age, sex, device type, and device revision/removal date) to each patient with AL (n = 260) and compared CIED-related infection, venous thrombosis/stenosis, and all-cause mortality between groups using a Cox proportional hazard model analysis. RESULTS: For a mean follow-up period of 11.2 ± 8.2 years, 14 (3.6%), 7 (1.8%), and 143 (36.7%) patients had a CIED-related infection, venous thrombosis/stenosis, or experienced all-cause mortality, respectively. The AL group had more comorbidities than the control group. Lead malfunction was the most common cause of abandonment (64.6%). After adjustment for covariates, no significant intergroup differences were noted in the risks of infection, venous thrombosis/stenosis, or all-cause mortality (adjusted hazard ratio [aHR] 2.52; 95% confidence interval [CI] 0.77-8.25; aHR 1.18; 95% CI 0.25-5.64; aHR 1.26; 95% CI 0.89-1.80, respectively). Patients with multiple ALs had increased risks of infection and all-cause mortality vs controls (aHR 8.61; 95% CI 2.13-34.84; aHR 2.42; 95% CI 1.17-5.00, respectively). CONCLUSION: Patients with a single AL showed similar risks of CIED-related infections, venous thrombosis/stenosis, and all-cause mortality as those without ALs, whereas those with multiple ALs showed increased risks of infection and all-cause mortality.


Assuntos
Desfibriladores Implantáveis , Marca-Passo Artificial , Infecções Relacionadas à Prótese , Trombose , Doenças Vasculares , Trombose Venosa , Humanos , Desfibriladores Implantáveis/efeitos adversos , Estudos Retrospectivos , Constrição Patológica/etiologia , Doenças Vasculares/etiologia , Trombose/etiologia , Trombose Venosa/etiologia , Marca-Passo Artificial/efeitos adversos , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/etiologia
3.
J Cardiovasc Electrophysiol ; 23(7): 757-63, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22353358

RESUMO

INTRODUCTION: The circadian and seasonal patterns of ventricular tachyarrhythmia (VTA) in patients with early repolarization syndrome (ERS) have not been determined. We compared the timing of VTAs in patients with ERS and Brugada syndrome (BS). METHODS AND RESULTS: We enrolled patients with ERS (n = 14) and BS (n = 53) who underwent implantable cardioverter defibrillator (ICD) implantation. The timing of VTAs, including cardiac arrest and appropriate shocks, was determined. During follow up of 6.4 ± 3.6 years in the ERS group and 5.0 ± 3.3 years in the BS group, 5 of 14 (36%) ERS and 10 of 53 (19%) BS patients experienced appropriate shocks (P = 0.37). Cardiac arrest showed a trend of nocturnal distribution peaking from midnight to early morning (P = 0.14 in ERS, P = 0.16 in BS). Circadian distribution of appropriate shocks showed a significant nocturnal peak in patients with ERS (P < 0.0001) but a trend toward a nocturnal peak in patients with BS (P = 0.08). There were no seasonal differences in cardiac arrest in patients with ERS and BS. However, patients with ERS showed a seasonal peak in appropriate shocks from spring to summer (P < 0.0001). There was no significant seasonal peak in patients with BS. The timing of VTAs (cardiac arrest plus appropriate shock) showed significant nocturnal distributions in patients with ERS and BS (P < 0.01, respectively). A significant clustering of VTAs was noted from spring to summer (P < 0.01) in patients with ERS, but not in patients with BS (P = 0.42). CONCLUSIONS: Incidence of VTAs showed marked circadian variations with night-time peaks in patients with ERS and BS.


Assuntos
Arritmias Cardíacas/terapia , Síndrome de Brugada/terapia , Ritmo Circadiano , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Cardioversão Elétrica/instrumentação , Estações do Ano , Taquicardia Ventricular/terapia , Fibrilação Ventricular/terapia , Adulto , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Síndrome de Brugada/diagnóstico , Síndrome de Brugada/fisiopatologia , Distribuição de Qui-Quadrado , Cardioversão Elétrica/efeitos adversos , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia , Estudos Retrospectivos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/fisiopatologia
4.
Pacing Clin Electrophysiol ; 33(12): 1497-503, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20636313

RESUMO

BACKGROUND: Catheter ablation targeting of complex fractionated atrial electrograms (CFAEs) is one of the techniques used for atrial fibrillation (AF) ablation. The ablation of sites showing a high-frequency spectral component (HFC) during sinus rhythm, known as AF nests, has been introduced as an adjunct to conventional ablation. Known locations of some AF nests are similar to CFAE sites. However, it has not been systematically evaluated whether these two targets represent the same foci. The purpose of this study was to compare the anatomical locations of these sites using an animal model of vagally mediated AF. METHODS: Five anesthetized open-chest dogs were evaluated. Atrial electrograms were obtained epicardially. AF was induced by burst atrial pacing with 20 Hz during vagal stimulation. A total of 15 sites (eight sites in right atrium and seven sites in left atrium) were evaluated in each animal. The CFAE was determined during AF according to the electrogram patterns. After sinus conversion, real-time spectrum analysis was used for AF nest assessment at the same location. RESULTS: The CFAE was observed at the high and mid sulcus terminalis areas, pulmonary vein antrum, and mid portion of the coronary sinus. Among them, only 60% of the CFAE sites showed HFC during sinus rhythm. In addition, some of the non-CFAE sites (22%) showed HFC during sinus rhythm. CONCLUSION: The CFAE sites were not the same as the AF nests in this animal model of vagally mediated AF. Therefore, these two types of ablation methods appear to target different substrates of AF.


Assuntos
Fibrilação Atrial/fisiopatologia , Técnicas Eletrofisiológicas Cardíacas , Nervo Vago/fisiopatologia , Animais , Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Seio Coronário/anatomia & histologia , Seio Coronário/fisiopatologia , Seio Coronário/cirurgia , Cães , Átrios do Coração/anatomia & histologia , Átrios do Coração/fisiopatologia , Átrios do Coração/cirurgia , Masculino , Veias Pulmonares/fisiopatologia , Veias Pulmonares/cirurgia , Resultado do Tratamento , Nervo Vago/cirurgia
5.
J Korean Med Sci ; 25(5): 712-5, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20436706

RESUMO

Maze operation could alter P wave morphology in electrocardiogram (ECG), which might prevent exact diagnosis of the cardiac rhythm of patients. However, characteristics of P wave in patients with sinus rhythm after the operation have not been elucidated systematically. Consecutive patients who underwent the modified Cox Maze operation from January to December 2007 were enrolled. The standard 12-lead ECG and echocardiography were evaluated in patients who had sinus rhythm at 6 months after the operation. The average axis of P wave was 65+/-30 degrees. The average amplitude of P wave was less than 0.1 mV in all 12-leads, with highest amplitude in V(1). The most common morphology of P wave was monophasic with positive polarity (49%), except aVR lead, which was different from those in patients with enlarged left atrium, characterized by large P-terminal force in the lead V(1). There were no significant differences in P-wave characteristics and echocardiographic parameters between patients with LA activity (30.6%) versus without LA activity (69.4%) at 6 months after the operation. In conclusion, the morphology of P wave in patients after Maze operation shows loss of typical ECG pattern of P mitrale: P wave morphology is small in amplitude, monophasic and with positive polarity.


Assuntos
Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Procedimentos Cirúrgicos Cardiovasculares/métodos , Eletrocardiografia/métodos , Sistema de Condução Cardíaco/fisiopatologia , Sistema de Condução Cardíaco/cirurgia , Frequência Cardíaca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
6.
J Korean Med Sci ; 25(10): 1462-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20890427

RESUMO

Transvenous left ventricular (LV) lead implantation is on the increase due to cardiac resynchronization therapy (CRT). However, there has been paucity of data on the prognosis of LV lead. Consecutive 32 patients with LV lead for CRT (n=22) or pacemaker (n=10) were subjected. Serial changes in pacing threshold and impedance along with lead-related complications were evaluated. Over 2 yr follow-up, there was no significant change in relative threshold voltage to the initial value (100%, 110%, 89.6%, and 79.6% at baseline, 1, 6, and 24 months respectively, P=0.62) as well as lead impedance (816±272, 650±178, 647±191, and 590±185 ohm at baseline, 1, 6, and 24 months respectively, P=0.80). The threshold change was not affected by lead position, lead polarity, and indication of lead implantation. The cumulative rates of lead revision were 6.3% (n=2) and 9.4% (n=3) in 6 month and 2 yr follow-up, respectively. One case of phrenic nerve capture at left lateral decubitus position was detected 1 month after the implantation. However, there were no serious complications over 2 yr period. In conclusion, transvenous LV lead implantation showed favorable long-term prognosis. Pacing parameters remained stable without significant changes over 2 yr follow-up.


Assuntos
Dispositivos de Terapia de Ressincronização Cardíaca , Ventrículos do Coração , Adulto , Idoso , Análise de Variância , Eletrofisiologia Cardíaca , Terapia de Ressincronização Cardíaca , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Disfunção Ventricular Esquerda/terapia
7.
Am Heart J ; 157(3): 576-83, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19249432

RESUMO

BACKGROUND: Contrast-induced nephropathy (CIN) is a leading cause of hospital-acquired renal failure and affects mortality and morbidity. There has been no study comparing the efficacy of N-acetylcysteine (NAC) and ascorbic acid that have potential for CIN prevention in patients with renal insufficiency. METHODS: We conducted a prospective randomized controlled trial. A total of 212 patients who had pre-existing renal impairment with basal creatinine clearance < or =60 mL/min and/or serum creatinine (SCr) level of > or =1.1 mg/dL, were randomized to have either high-dose NAC (1,200 mg orally twice a day before and on the day of coronary catheterization, n = 106) or ascorbic acid (3 g and 2 g orally before, and 2 g twice after coronary catheterization with a 12-hour interval, n = 106). The primary end point was the maximum increase of SCr level, and the secondary end point was the incidence of CIN. RESULTS: The maximum increase of SCr level was significantly lower in NAC group than in ascorbic acid group as follows: -0.03 +/- 0.18 mg/dL versus 0.04 +/- 0.20 mg/mL, respectively (P = .026). Patients with diabetes or who had received a high dose of contrast media experienced significantly less rise of SCr level with NAC than ascorbic acid; in diabetic subgroup, -0.05 +/- 0.22 mg/dL versus 0.09 +/- 0.29 mg/mL, respectively (P = .020); in patients with high dose of dye, -0.03 +/- 0.17 mg/dL versus 0.04 +/- 0.21 mg/mL, respectively (P = .032). The incidence of CIN, the secondary end point, tended to be in favor of NAC rather than ascorbic acid, 1.2% versus 4.4%, respectively (P = .370). Notably, among the diabetes patients, the NAC significantly lowered CIN rate than ascorbic acid, 0% (0/38) versus 12.5% (4/32), respectively (P = .039). CONCLUSION: High-dose NAC seems more beneficial than ascorbic acid in preventing contrast-induced renal function deterioration in patients, especially diabetic patients, with renal insufficiency undergoing coronary angiography.


Assuntos
Acetilcisteína/uso terapêutico , Antioxidantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Meios de Contraste/efeitos adversos , Sequestradores de Radicais Livres/uso terapêutico , Insuficiência Renal/induzido quimicamente , Insuficiência Renal/prevenção & controle , Acetilcisteína/administração & dosagem , Idoso , Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Comorbidade , Angiografia Coronária , Creatinina/sangue , Diabetes Mellitus/epidemiologia , Feminino , Sequestradores de Radicais Livres/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal/sangue , Insuficiência Renal/epidemiologia
8.
Am Heart J ; 155(3): 499.e1-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18294484

RESUMO

BACKGROUND: Contrast media cause oxidative stress, which has been suggested as one possible mechanism responsible for contrast-induced nephropathy. Statins appear to have pleiotropic effects, including antioxidant properties. We investigated to determine whether simvastatin pretreatment reduces the risk of contrast-induced nephropathy in a high-risk population of patients with renal insufficiency undergoing coronary angiography. METHODS: We conducted a prospective, randomized, double-blind, placebo-controlled, 2-center trial, involving 247 consecutive patients with chronic renal insufficiency (calculated creatinine clearance < or = 60 mL/min and/or serum creatinine > or = 1.1 mg/dL) undergoing coronary angiography. Patients were randomized to simvastatin (n = 124; 160 mg total, 40 mg orally every 12 hours starting the evening before and ending the morning after the procedure) or placebo (n = 123). All patients received pre - and postprocedure hydration. The iso-osmolar contrast agent iodixanol was used for coronary angiography in all patients. RESULTS: There was no difference between simvastatin and placebo in mean peak increase in serum creatinine measured within 48 hours after coronary angiography, the primary study end point (0.002 +/- 0.164 vs 0.017 +/- 0.230 mg/mL respectively, P = .559). The incidence of contrast-induced nephropathy, a secondary end point defined as increase of either > or = 25% or > or = 0.5 mg/dL in serum creatinine, was 2.5% in simvastatin-treated patients (3/118) and 3.4% in placebo-treated patients (4/118), a nonsignificant difference (P = 1.00). There were also no differences between the 2 groups in length of hospital stay or 1- and 6-month clinical outcomes. CONCLUSIONS: Simvastatin pretreatment for short-term at high dose do not prevent renal function deterioration after administration of contrast medium in patients with baseline renal insufficiency undergoing coronary angiography.


Assuntos
Meios de Contraste/efeitos adversos , Angiografia Coronária/efeitos adversos , Doença das Coronárias/diagnóstico por imagem , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Insuficiência Renal/complicações , Insuficiência Renal/prevenção & controle , Sinvastatina/administração & dosagem , Administração Oral , Idoso , Doença das Coronárias/complicações , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Incidência , Coreia (Geográfico)/epidemiologia , Masculino , Estudos Prospectivos , Insuficiência Renal/induzido quimicamente , Insuficiência Renal/epidemiologia , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Ácidos Tri-Iodobenzoicos/efeitos adversos
9.
Am J Cardiol ; 100(7): 1153-6, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17884380

RESUMO

Chronic atrial fibrillation (AF) is common in patients with mitral stenosis (MS). Because AF induces electrical and mechanical remodeling of the left atrium, left atrial (LA) compliance is likely to be changed in its presence. This study was performed to investigate the influence of AF on LA compliance in patients with moderate to severe MS. Data were analyzed for 356 patients (282 women; mean age 40 +/- 11 years; range 17 to approximately 71) who were registered in the percutaneous mitral commissurotomy database. Mean LA pressure was lower (21 +/- 7 vs 26 +/- 8 mm Hg; p <0.001), but LA volume was higher in the AF than sinus-rhythm group (126 +/- 62 vs 74 +/- 27 ml; p <0.001), indicating higher LA compliance, which was further confirmed by lower LA v wave at catheterization in the AF group (27 +/- 9 for AF vs 32 +/- 10 mm Hg for sinus rhythm; p <0.001). In conclusion, the presence of AF has a significant influence on LA compliance in patients with moderate to severe MS.


Assuntos
Fibrilação Atrial/complicações , Átrios do Coração/fisiopatologia , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Adolescente , Adulto , Idoso , Doença Crônica , Ecocardiografia Doppler , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/complicações , Estenose da Valva Mitral/fisiopatologia , Estudos Retrospectivos
10.
J Electrocardiol ; 40(6): 535-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17669416

RESUMO

We report a 34-year-old female patient with preexcitation electrocardiogram and recurrent paroxysmal palpitations. Standard 12-lead electrocardiogram showed minimal preexcitation with normal PR interval and normal frontal QRS axis. The electrophysiologic study showed normal AH intervals, short HV intervals, and no change in the degree of preexcitation by rapid atrial pacing. These findings were compatible with the fasciculoventricular pathway. Typical atrioventricular nodal reentrant tachycardia with narrow QRS complex and normal HV interval was induced reproducibly by programmed electrical stimulation. Slow pathway was ablated successfully with radiofrequency catheter ablation, and then the patient remained asymptomatic during a follow-up of 12 months. Although the fasciculoventricular pathway is rare and supraventricular tachycardia in a patient with fasciculoventricular pathway may mimic Wolff-Parkinson-White syndrome, possibility of typical atrioventricular nodal reentrant tachycardia with fasciculoventricular pathway should be considered as a mechanism of supraventricular tachycardia in a patient showing preexcitation electrocardiogram.


Assuntos
Bloqueio de Ramo/complicações , Bloqueio de Ramo/diagnóstico , Eletrocardiografia , Sistema de Condução Cardíaco/anormalidades , Taquicardia por Reentrada no Nó Atrioventricular/diagnóstico , Taquicardia por Reentrada no Nó Atrioventricular/etiologia , Adulto , Feminino , Humanos
11.
Circulation ; 112(9 Suppl): I14-9, 2005 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-16159806

RESUMO

BACKGROUND: Atrial fibrillation (AF) has been reported to be a predisposing factor for the progression of TR in patients with previous mitral or combined mitral/aortic valve surgery. We hypothesized that the maze operation (MAZE) can prevent the progression of tricuspid regurgitation (TR) in these patients. METHODS AND RESULTS: We analyzed 170 patients (age, 45.5+/-10.9 years) who had undergone mitral or combined mitral/aortic valve surgery. On the basis of preoperative rhythm, patients were divided into 3 groups; GrI was composed of 44 patients with sinus rhythm, GrII of 48 who had undergone MAZE, and GrIII of 78 with AF who had not undergone MAZE. Echocardiographic examinations were performed before, immediately after, and 92.2+/-17.2 (range, 50 to 131) months after surgery. Preoperative and immediate postoperative clinical and echocardiographic parameters were similar among the groups. Insignificant TR at the immediate postoperative examination worsened with time in 7.3% of GrI (3 of 41), 12.8% of GrII (6 of 47), and 38.8% of GrIII (26 of 67) patients at the final examination (P=0.63 for GrI versus GrII, P=0.001 for GrI versus GrIII, P=0.005 for GrII versus GrIII). The incidence of significant TR at the final echocardiographic examination was higher in GrIII (39.7%) compared with GrI (9.1%) and GrII (14.6%) (P=0.001 for GrI versus GrIII, P=0.005 for GrII versus GrIII), whereas GrI and GrII did not show any difference (P=0.63). By multivariate analysis, the only factor identified to prevent TR progression was the group factor (GrI and GrII versus GrIII, P=0.002 and P=0.005, respectively). In a subgroup analysis of GrII according to the presence or absence of atrial mechanical activity, the absence of atrial mechanical activity was identified as an independent parameter for the progression of TR (P=0.001). CONCLUSIONS: AF predisposes patients undergoing mitral valve surgery to the progression of TR, which can be prevented by MAZE. This additional benefit of MAZE is largely dependent on the restoration and maintenance of atrial mechanical function.


Assuntos
Valva Aórtica/cirurgia , Fibrilação Atrial/cirurgia , Ablação por Cateter , Valva Mitral/cirurgia , Insuficiência da Valva Tricúspide/cirurgia , Adolescente , Adulto , Idoso , Insuficiência da Valva Aórtica/complicações , Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/cirurgia , Fibrilação Atrial/complicações , Fibrilação Atrial/fisiopatologia , Comorbidade , Progressão da Doença , Ecocardiografia , Ecocardiografia Doppler , Ecocardiografia Doppler em Cores , Feminino , Seguimentos , Átrios do Coração/fisiopatologia , Átrios do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/cirurgia , Estenose da Valva Mitral/complicações , Estenose da Valva Mitral/cirurgia , Período Pós-Operatório , Reoperação/estatística & dados numéricos , Fatores de Risco , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/etiologia , Insuficiência da Valva Tricúspide/fisiopatologia
12.
J Am Coll Cardiol ; 46(4): 633-7, 2005 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-16098427

RESUMO

OBJECTIVES: This study was performed to evaluate the feasibility of the physiologic assessment of jailed side branches using fractional flow reserve (FFR) and to compare the measured FFR with the stenosis severity assessed by quantitative coronary angiography (QCA). BACKGROUND: It is not well-known which side branches should be treated after stent implantation at main branches and how to assess the functional significance of these lesions. METHODS: Ninety-seven jailed side branch lesions (vessel size > 2.0 mm, percent stenosis > 50% by visual estimation) after stent implantation at main branches were consecutively enrolled. The FFR was measured using a pressure wire at 5 mm distal and proximal to the ostial lesion of the jailed side branch. RESULTS: The FFR measurement was successful in 94 lesions. Mean FFRs were 0.94 +/- 0.04 and 0.85 +/- 0.11 at the main branches and jailed side branches, respectively. There was a negative correlation between the percent stenosis and FFR (r = -0.41, p < 0.001). However, no lesion with < 75% stenosis had FFR < 0.75. Among 73 lesions with > or = 75% stenosis, only 20 lesions were functionally significant. CONCLUSIONS: The FFR measurement in jailed side branch lesions is both safe and feasible. Quantitative coronary angiography is unreliable in the assessment of the functional severity of jailed side branch lesions, and measurement of FFR suggests that most of these lesions do not have functional significance.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Angiografia Coronária/instrumentação , Circulação Coronária/fisiologia , Estenose Coronária/fisiopatologia , Estenose Coronária/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Stents
13.
Am J Cardiol ; 98(5): 659-61, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16923456

RESUMO

This study was performed to identify echocardiographic parameters related to postoperative clinical outcome in patients who undergo surgery for severe tricuspid regurgitation after mitral valve surgery. Eighteen patients (2 men, 16 women; mean age 58 years) were prospectively enrolled. Echocardiographic examinations were performed before and 15 +/- 7 months after surgery. Favorable postoperative clinical outcome was defined as an improvement of > or = 1 in New York Heart Association functional class or a > 25% increase in respiratory variation of inferior vena cava diameter. Operative mortality was 11% (2 of 18). Of the 16 survivors, 9 (56%) achieved favorable postoperative clinical outcomes. Only systolic tricuspid annulus velocity (S'T) was found to be associated with postoperative clinical outcome (favorable vs unfavorable postoperative clinical outcome 12.9 +/- 2.1 vs 9.7+/- 1.7 cm/s, p < 0.05). For S'T < 9.5 cm/s, the sensitivity, specificity, and positive and negative predictive values for predicting an unfavorable postoperative clinical outcome were 67%, 100%, 100%, and 75%, respectively. In conclusion, S(T') can predict postoperative clinical outcomes in these patients.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Procedimentos Cirúrgicos Cardíacos/métodos , Valva Mitral/cirurgia , Insuficiência da Valva Tricúspide/cirurgia , Valva Tricúspide/fisiopatologia , Ecocardiografia Doppler , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Reoperação , Índice de Gravidade de Doença , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/etiologia , Insuficiência da Valva Tricúspide/fisiopatologia
14.
Am J Cardiol ; 98(2): 236-42, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16828600

RESUMO

We performed a prospective study of patients with chronic right ventricular (RV) dilation to determine the factors associated with the degree of functional tricuspid regurgitation (FTR). We prospectively enrolled 64 patients with chronic RV dilation and measured right atrial (RA) area, RV area and its fractional area change (RVFAC), tricuspid annular diameter and contraction, tricuspid valve (TV) tethering area, and systolic pulmonary artery pressure. We also measured the RV eccentricity index and the RV sphericity index for simple presentation of RV geometry. Regurgitant orifice area of FTR was obtained for the quantification of FTR. End-systolic RV eccentricity index (r=0.73), end-diastolic RV eccentricity index (r=0.56), RA area (r=0.49), TV tethering area (r=0.37), age (r=0.31), end-systolic (r=0.42) and end-diastolic (r=0.30) tricuspid annular diameters, and left ventricular ejection fraction (r=-0.37) were significantly related to the regurgitant orifice area of FTR in univariate analysis. However, RV area, RVFAC, and systolic pulmonary artery pressure were not. In multivariate analysis, the end-systolic RV eccentricity index (p<0.001), TV tethering area (p=0.003), and end-diastolic tricuspid annulus diameter (p=0.007) showed the independent associations with regurgitant orifice area of FTR. The sensitivities and specificities for predicting more than mild FTR were found to be 79% and 82% with an end-systolic RV eccentricity index>2.0, 69% and 73% with an end-systolic tethering area>1.0 cm2, and 64% and 59% for an end-systolic tricuspid annulus diameter>3.9 cm, respectively. FTR severity was found to show the best correlation with the end-systolic RV eccentricity index. In conclusion, these findings underscore the importance of eccentric RV dilation for determining FTR severity and should lead to the development of more rational surgical approaches to FTR beyond TV annuloplasty.


Assuntos
Ecocardiografia Doppler , Contração Miocárdica/fisiologia , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Pressão Propulsora Pulmonar/fisiologia , Curva ROC , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Volume Sistólico/fisiologia , Insuficiência da Valva Tricúspide/fisiopatologia
15.
Arterioscler Thromb Vasc Biol ; 25(6): 1154-60, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15802621

RESUMO

OBJECTIVE: New vessel formation is a dynamic process of attachment, detachment, and reattachment of endothelial cells (ECs) and endothelial progenitor cells (EPCs) with each other and with the extracellular matrix (ECM). Integrin-linked kinase (ILK) plays a pivotal role in ECM-mediated signaling. Therefore, we investigated the role of ILK in ECs and EPCs during neovascularization. METHODS AND RESULTS: In human umbilical cord vein ECs and EPCs, endogenous ILK expression, along with subsequent cell survival signals phospho-Akt and phospho-glycogen synthase kinase 3beta, was reduced after anchorage or nutrient deprivation. Even brief anchorage deprivation resulted in retarded capillary tube formation by ECs. Adenoviral ILK gene transfer in ECs and EPCs reversed the decrease in cell survival signals after anchorage or nutrient deprivation, leading to enhanced survival, reduced apoptosis, and significantly accelerated the functional recovery after reattachment. And ILK overexpressing EPCs significantly improved blood flow recovery and prevented limb loss in nude mice hindlimb ischemia model. Furthermore, the efficacy of systemic delivery was equivalent to local injection of ILK-EPCs. CONCLUSIONS: ILK overexpression protects ECs and EPCs from anchorage- or nutrient-deprived stress and enhances neovascularization, suggesting that ILK is an optimal target gene for genetically modified cell-based therapy. Neovascularization is a dynamic process of detachment and reattachment of ECs and EPCs. Endogenous ILK expression was decreased in various stress conditions, and the gene transfer of ILK protected ECs and EPCs from temporary anchorage or nutrient deprivation. Furthermore, ILK gene transfer in EPCs significantly enhanced neovascularization in vivo.


Assuntos
Endotélio Vascular/citologia , Endotélio Vascular/enzimologia , Neovascularização Fisiológica/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Células-Tronco/citologia , Células-Tronco/enzimologia , Animais , Apoptose/fisiologia , Adesão Celular/fisiologia , Divisão Celular/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Feminino , Regulação Enzimológica da Expressão Gênica , Técnicas de Transferência de Genes , Humanos , Isquemia/metabolismo , Isquemia/patologia , Isquemia/fisiopatologia , Camundongos , Camundongos Nus , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais/fisiologia , Veias Umbilicais/citologia
16.
Circulation ; 108(23): 2918-25, 2003 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-14568896

RESUMO

BACKGROUND: Endothelial progenitor cells (EPCs) play a pivotal role in repair and regeneration of damaged vessels. We investigated the role of mobilized EPCs in the healing process after intravascular radiation therapy. METHODS AND RESULTS: One iliac artery of hypercholesterolemic rabbits was subjected to balloon injury and intravascular radiation with a Re-188 balloon and the contralateral iliac artery to balloon injury only. Rabbits received granulocyte-macrophage colony-stimulating factor (recombinant human GM-CSF) (60 microg/d subcutaneously) daily for 1 week, either 7 days before the angioplasty or at the time of angioplasty. Control rabbits received human albumin. GM-CSF significantly increased the double-positive (CD31+ and KDR+) fraction in peripheral blood monocytes and showed a higher number of EPCs than albumin after culture and, furthermore, enhanced migration and incorporation of EPCs. In the albumin group, intravascular radiation therapy reduced neointimal hyperplasia but delayed reendothelialization and aggravated monocyte infiltration. GM-CSF treatment significantly accelerated the reendothelialization and inhibited monocyte infiltration (reendothelialization index, 81+/-13% in the GM-CSF radiation [n=7] versus 30+/-11% in the control radiation [n=9] at 2 weeks, P<0.01). GM-CSF treatment produced an additional significant reduction in neointimal formation at 14 and 28 days after injury in the intravascular radiation groups (intima to media ratio, 0.14+/-0.11 in the GM-CSF radiation [n=5] versus 0.36+/-0.07 in the control radiation [n=5] at 4 weeks, P<0.01). CONCLUSIONS: GM-CSF treatment mobilizes EPCs, accelerates reendothelialization, and reduces monocytes infiltration after intravascular radiation therapy, suggesting that stem cell mobilization is a promising strategy for enhancing the vascular healing process after cytotoxic angioplasty.


Assuntos
Cateterismo/efeitos adversos , Endotélio Vascular/fisiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Artéria Ilíaca/lesões , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Lesões por Radiação/terapia , Regeneração , Animais , Endotélio Vascular/lesões , Endotélio Vascular/patologia , Células Espumosas/efeitos da radiação , Humanos , Hipercolesterolemia/patologia , Hiperplasia , Artéria Ilíaca/efeitos da radiação , Masculino , Coelhos , Radioisótopos/efeitos adversos , Proteínas Recombinantes/farmacologia , Regeneração/efeitos da radiação , Rênio/efeitos adversos , Túnica Íntima/patologia , Túnica Íntima/efeitos da radiação , Cicatrização
17.
J Am Coll Cardiol ; 43(11): 2097-101, 2004 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-15172419

RESUMO

OBJECTIVES: This study was performed to validate the clinical usefulness of measuring the time difference between onset of mitral inflow and onset of early diastolic mitral annulus velocity (T(E'-E)) for the evaluation of left ventricular (LV) diastolic function. BACKGROUND: In recent studies, T(E'-E) correlated well with the time constant of LV pressure decay (tau), and the ratio of IVRT/T(E'-E), where IVRT is isovolumic relaxation time, was useful in the prediction of elevated LV filling pressure. METHODS: Simultaneous left heart catheterization and Doppler echocardiography were performed in 40 patients. RESULTS: The T(E'-E) was evaluated in the same cardiac cycle and in the same hemodynamic status in 31 patients. Despite the wide range of tau (31 to 70 ms), there was no delay in the onset of mitral annulus velocity compared with the onset of mitral inflow (T(E'-E) = 0) in 27 patients and, therefore, T(E'-E) did not correlate with tau. Only three patients showed prolongation in T(E'-E), and all three showed tau >or=50 ms and pre-A-wave pressure >or=18 mm Hg. In one patient, mitral annulus velocity began earlier than the onset of mitral inflow. Because T(E'-E) was 0 in the majority of patients, the LV filling pressure could not be predicted by the previously suggested index of IVRT/T(E'-E.) CONCLUSIONS: In contrast to previous studies, T(E'-E) did not correlate with tau, and IVRT/ T(E'-E) could not be applied in the prediction of filling pressure, because of the limitation of a zero denominator. However, prolongation of T(E'-E) might suggest an elevated filling pressure in the setting of prolonged tau.


Assuntos
Ecocardiografia Doppler/métodos , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Adulto , Idoso , Velocidade do Fluxo Sanguíneo , Diástole , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Tempo
18.
J Am Coll Cardiol ; 40(11): 1976-83, 2002 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-12475458

RESUMO

OBJECTIVES: This study was designed to investigate a possible mechanism of postprandial angina. BACKGROUND: Postprandial angina has been recognized for more than two centuries; however, its mechanism is still controversial. The most widely accepted mechanism involves increased myocardial oxygen demand after food intake. Recently, the redistribution in coronary blood flow (CBF) was suggested as a possible mechanism. METHODS: Twenty young, healthy volunteer controls and 20 patients with significant stenosis in the left anterior descending (LAD) or left main coronary artery were enrolled in the study. Coronary blood flow was evaluated in the distal LAD by using transthoracic Doppler echocardiography before and 15, 30, 45, and 60 min after food intake. In the CBF curve, the time velocity integral of diastolic flow (Dtvi) and the product of Dtvi and heart rate (HR) were measured. In six patients, these measurements were repeated after successful coronary intervention. RESULTS: In the healthy volunteer controls, Dtvi and Dtvi x HR increased after food intake with a peak value at 15 min, which indicates the presence of postprandial surge in the CBF. Fasting values and peak values at 15 min were significantly different (Dtvi: 15.1 +/- 4.9 cm/s vs. 18.9 +/- 5.9 cm/s, p = 0.04, Dtvi x HR: 862.2 +/- 261.5 cm/min vs. 1,174.2 +/- 307.5, p = 0.002). In contrast with the controls, despite postprandial increase in double product (HR x blood pressure), Dtvi and Dtvi x HR in the patient group decreased after food intake, with a nadir value at 45 min. Fasting values and nadir values at 45 min were significantly different (Dtvi: 24.0 +/- 19.6 cm/s vs. 19.3 +/- 17.1 cm/s, p < 0.001, Dtvi x HR: 1,449.6 +/- 1,044.0 cm/min vs. 1,273.4 +/- 1,000.9 cm/min, p = 0.002). In six patients, the CBF pattern resumed the normal pattern of postprandial surge in the CBF after successful coronary intervention. CONCLUSIONS: Results of our study suggest that "steal phenomenon" may play a role in the mechanism of postprandial angina.


Assuntos
Angina Pectoris/fisiopatologia , Artérias/fisiopatologia , Velocidade do Fluxo Sanguíneo/fisiologia , Circulação Coronária/fisiologia , Estenose Coronária/fisiopatologia , Estenose Coronária/cirurgia , Vasos Coronários/fisiopatologia , Período Pós-Prandial/fisiologia , Adulto , Idoso , Pressão Sanguínea/fisiologia , Estenose Coronária/epidemiologia , Ingestão de Alimentos/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Prevalência , Volume Sistólico/fisiologia , Resultado do Tratamento
19.
Arterioscler Thromb Vasc Biol ; 23(8): 1364-9, 2003 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-12805073

RESUMO

OBJECTIVE: Glycogen synthase kinase (GSK)-3beta is a crucial factor in many cellular signaling pathways and may play an important role in smooth muscle proliferation and apoptosis after angioplasty. METHODS AND RESULTS: To investigate the effect of GSK-3beta modulation on neointima formation, smooth muscle proliferation, and apoptosis after balloon injury in vivo, we delivered adenoviral vectors expressing the constitutively active form of GSK-3beta (GSK-S9A: 9th serine switched to alanine) or a control gene into rat carotid arterial segments after balloon injury with a 2F Fogarty catheter. Viral infusion mixtures (5x108 pfu) were incubated in the arterial lumen for 20 minutes, and the effects of gene delivery were evaluated 3 days and 2 weeks after gene delivery with morphometry and immunohistochemical staining for proliferating and apoptotic cells. There were no significant differences in intimal, medial, and lumen areas at 3 days after the procedure. However, 2 weeks after gene delivery, the active GSK-3beta gene transfer resulted in a significantly lower intima to media ratio (0.29+/-0.06 versus 0.86+/-0.09, P<0.01) and a greater lumen area (0.41+/-0.02 versus 0.31+/-0.01 mm2, P<0.01) compared with the control gene transfected group. This was attributable to a significant reduction in intimal area (0.05+/-0.01 versus 0.15+/-0.02 mm2, P<0.01), whereas the medial area was similar (0.17+/-0.01 versus 0.18+/-0.01 mm2, P=0.21). Proliferation index was significantly reduced both at 3 days and 2 weeks in the active GSK-3beta gene transferred group (2.97+/-0.29% versus 5.71+/-0.50%, P<0.01). In addition, apoptotic index, which was not significantly different between the 2 groups at 3 days, was significantly higher in the active GSK-3beta gene transferred group at 2 weeks (3.14+/-0.68% versus 22.7+/-1.63%, n=10, P<0.01, for control versus active GSK-3beta gene transfer). CONCLUSIONS: In vivo delivery of the active GSK-3beta gene inhibits smooth muscle proliferation, sustains apoptosis, and reduces neointima formation after balloon injury in rats and may be a future therapeutic target to limit neointima hyperplasia after angioplasty.


Assuntos
Apoptose/efeitos dos fármacos , Lesões das Artérias Carótidas/tratamento farmacológico , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/farmacologia , Animais , Lesões das Artérias Carótidas/etiologia , Lesões das Artérias Carótidas/patologia , Cateterismo/efeitos adversos , Endotélio Vascular , Expressão Gênica , Técnicas de Transferência de Genes , Quinase 3 da Glicogênio Sintase/análise , Glicogênio Sintase Quinase 3 beta , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Ratos , Ratos Sprague-Dawley , Recidiva , Túnica Íntima/efeitos dos fármacos , Túnica Íntima/patologia
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