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1.
Pediatr Cardiol ; 41(3): 591-598, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32055941

RESUMO

To identify suitable cases and reduce failure/complication rates for percutaneous ventricular septal defect (VSD) closure, we aimed to (1) study causes of device failure and (2) compare outcomes with different VSD types and devices in a high-volume single center with limited resources. Retrospective data of 412 elective percutaneous VSD closure of isolated congenital VSDs between 2003 and 2017 were analyzed. Out of 412, 363 were successfully implanted, in 30 device implantation failed, and in 19 the procedure was abandoned. Outcome was assessed using echocardiography, electrocardiography, and catheterization data (before procedure, immediately after and during follow-up). Logistic regression analyses were performed to assess effects of age, VSD type, and device type and size on procedural outcome. Median [interquartile range] age and body surface area were 6.6 [4.1-10.9] years and 0.7 [0.5-1.0] m2, respectively. Device failure was not associated with age (p = 0.08), type of VSD (p = 0.5), device type (p = 0.2), or device size (p = 0.1). Device failure occurred in 7.6% of patients. As device type is not related to failure rate and device failure and complication risk was not associated with age, it is justifiable to use financially beneficial ductal devices in VSD position and to consider closure of VSD with device in clinically indicated children.


Assuntos
Comunicação Interventricular/terapia , Dispositivo para Oclusão Septal/normas , Cateterismo Cardíaco , Criança , Pré-Escolar , Bases de Dados Factuais , Ecocardiografia , Eletrocardiografia , Falha de Equipamento/estatística & dados numéricos , Feminino , Humanos , Masculino , Estudos Retrospectivos , Dispositivo para Oclusão Septal/economia , Resultado do Tratamento
2.
Ann Pediatr Cardiol ; 10(3): 245-247, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28928610

RESUMO

INTRODUCTION: The early identification of vulnerable pediatric cardiac surgery patients can help clinicians provide them with timely support. Heart-type fatty acid-binding protein. (H-FABP) is an early biomarker of myocardial injury in acute myocardial infarction in adults. In this study, we evaluated the correlations between postoperative H-FABP, creatine kinase-myocardial band (CK-MB), troponin-I, total bypass time, and clinical outcomes. METHODS: In 32 pediatric patients that underwent ventricular septal defect. closure we measured H-FABP, troponin-I and CK-MB preoperatively and 1, 3, and 6 h after aortic declamping. Spearman's Rho correlations were calculated between laboratory and clinical parameters including inotropic support duration, aortic cross-clamp time, total bypass time, ventilation-weaning-time, and total Intensive Care Unit stay. RESULTS: H-FABP, CK-MB, troponin-I, and total bypass time have a similarly weak to moderate correlation with clinical outcome measures. CONCLUSIONS: The predictive value of H-FABP for clinical outcome is not stronger than that of CK-MB, Troponin-I, or bypass times.

3.
Neonatology ; 112(4): 324-329, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28768288

RESUMO

BACKGROUND: Barriers to widespread implementation of pulse oximetry screening of critical congenital heart defects (CCHD) in newborns include increasing trends of out-of-hospital births and cost of equipment. In recent years, smartphone-compatible pulse oximeters have appeared on the market, but the validity of such devices in the setting of CCHD screening has not been evaluated. OBJECTIVES: To compare the performance in CCHD screening of a smartphone-paired pulse oximeter (Masimo iSpO2-Rx™) and a hospital-grade pulse oximeter (Masimo Radical-7™). METHODS: Preductal (right hand) and postductal (either foot) saturations were determined in a population of 201 term newborns by 2 independent teams, one using the Radical-7 and the other using the iSpO2-Rx. Bland-Altman analysis was applied to calculate mean bias and 95% limits of agreement between the 2 pulse oximeters. RESULTS: For the preductal oxygen saturation, the mean bias (Radical-7 minus iSpO2-Rx) was -0.08 (SD 1.76) and the lower and upper limits of agreement were -3.52 and 3.36, respectively. For the postductal oxygen saturation, the mean bias was -0.11 (SD 1.68) and the lower and upper limits of agreement were -3.49 and 3.18, respectively. In addition, the iSpO2-Rx provided reliable measurements of saturations below 95% in a group of 12 infants admitted to the neonatal intensive care unit. CONCLUSIONS: Our data suggest that CCHD screening with the Masimo iSpO2-Rx is feasible and accurate. The use of reliable smartphone-paired pulse oximeters may contribute to the extension of CCHD screening to home births and low resource settings.


Assuntos
Diagnóstico por Computador/instrumentação , Cardiopatias Congênitas/diagnóstico , Aplicativos Móveis , Triagem Neonatal/instrumentação , Oximetria/instrumentação , Oxigênio/sangue , Smartphone , Biomarcadores/sangue , Estado Terminal , Cardiopatias Congênitas/sangue , Humanos , Recém-Nascido , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
5.
J Frailty Aging ; 5(2): 111-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27224502

RESUMO

BACKGROUND: The field of aging studies continues to better understand between-racial-group health disparities. Previous work provides empirical evidence for a statistical relationship between perceived discrimination and adverse health across all age groups. SPECIFIC AIM: We contribute to the literature by investigating the quantitative relationship between Perceived Ethnic Discrimination (PED), Self-Rated Physical Health (SR-PH), Self-Rated Mental Health (SR-MH), and their combined score (SR-PH-MH). SETTING AND DESIGN: The cross-sectional observational study used data collected between 2002 and 2004 from the National Latino and Asian American Study (n=4,559; average age=41; 54% female; 18% Mexican; 36% Non-Mexican Latinos; 12% Chinese; 31% Non-Chinese Asians). We provide descriptive statistics for those below and at or above age 65. RESULTS: Multivariable linear models adjusting for age, sex, ethnicity, education, body mass index, and neighborhood perception provide evidence that although a small effect, PED explains between-people variance in SR-PH (ß=-0.01; α=0.001), SR-MH (ß=-0.03; α=0.001), and SR-PH-MH (ß=-0.04; α=0.001). CONCLUSIONS: The analysis supports arguments that PED has a non-random association with health. As we continue to explore novel measures of frailty, markers of social stress should be considered.


Assuntos
Asiático , Idoso Fragilizado , Hispânico ou Latino , Racismo/psicologia , Idoso , Idoso de 80 Anos ou mais , Asiático/psicologia , Asiático/estatística & dados numéricos , Estudos Transversais , Autoavaliação Diagnóstica , Feminino , Idoso Fragilizado/psicologia , Idoso Fragilizado/estatística & dados numéricos , Disparidades nos Níveis de Saúde , Hispânico ou Latino/psicologia , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Autoavaliação (Psicologia) , Mudança Social , Percepção Social , Estados Unidos/etnologia
6.
Eur J Cardiothorac Surg ; 49(5): 1403-10, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26464453

RESUMO

OBJECTIVES: Sildenafil has strong cardiac preconditioning properties in animal studies and has a safe side-effect profile in children. Therefore, we evaluated the application of Sildenafil preconditioning to reduce myocardial ischaemia/reperfusion injury in children undergoing surgical ventricular septal defect (VSD) closure. METHODS: This is a randomized, double-blind study. Children (1-17 years) undergoing VSD closure were randomized into three groups: placebo (Control group), preconditioning with 0.06 mg/kg (Sild-L group) and 0.6 mg/kg Sildenafil (Sild-H group). PRIMARY ENDPOINT: troponin release. CK-MB, Troponin I, inflammatory response (IL-6 and TNF-α), bypass and ventilation weaning times, inotropy score and echocardiographic function were assessed. Data expressed as median (range), and a value of P < 0.05 was considered significant. RESULTS: Thirty-nine patients were studied (13/group). Aortic cross-clamp time was similar [27 (18-85) and 27 (12-39) min] in the Control and Sild-L groups, respectively, but significantly longer [39 (20-96) min] in the Sild-H group when compared with the Control group. Area under the curve of CK-MB release was 1105 (620-1855) h ng/ml in the Control group, 1672 (564-2767) h ng/ml in the Sild-L group and was significantly higher in the Sild-H group [1695 (1252-3377) h ng/ml] when compared with the Control group. There were no significant differences in inflammatory response markers, cardiopulmonary bypass and ventilation weaning times, inotropy scores and echocardiographic function between the groups. CONCLUSIONS: In this small study, Sildenafil failed to reduce myocardial injury in children undergoing cardiac surgery, nor does it alter cardiac function, inotropic needs or postoperative course. A subclinical increase in cardiac enzyme release after Sildenafil preconditioning cannot be excluded. CLINICAL TRIALS REGISTRY: CTRI/2014/03/004468.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/métodos , Precondicionamento Isquêmico Miocárdico/efeitos adversos , Precondicionamento Isquêmico Miocárdico/métodos , Citrato de Sildenafila/uso terapêutico , Adolescente , Pressão Sanguínea/efeitos dos fármacos , Procedimentos Cirúrgicos Cardíacos/mortalidade , Procedimentos Cirúrgicos Cardíacos/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Coração/efeitos dos fármacos , Coração/fisiopatologia , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Precondicionamento Isquêmico Miocárdico/mortalidade , Precondicionamento Isquêmico Miocárdico/estatística & dados numéricos , Masculino , Citrato de Sildenafila/administração & dosagem , Citrato de Sildenafila/farmacologia
7.
Heart ; 101(10): 788-93, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25539944

RESUMO

BACKGROUND: Melody valved stents (Medtronic Inc, Minneapolis, Minnesota, USA) have become a very competitive therapeutic option for pulmonary valve replacement in patients with congenital heart disease. After adequate prestenting of the right ventricular outflow tract (RVOT) Melody valved stents have a good medium term functional result but are exposed to infective endocarditis (IE). PATIENTS AND METHODS: Retrospective study of tertiary centre Congenital Heart Disease database; to compare incidence of IE in three different types of valved conduits in RVOT: Melody valved stent, cryopreserved homograft (European Homograft Bank) and Contegra graft (Medtronic Inc). RESULTS: Between 1989 and 2013, 738 conduits were implanted in 677 patients. 107 Melody valved stents were implanted in 107 patients; IE occurred in 8 (7.5%) patients during a follow-up of 2.0 years (IQR 2.4 years, range 0.3-7.8 years). 577 Homografts were implanted in 517 patients; IE occurred in 14 patients (2.4%) during a median follow-up of 6.5 years (IQR 9.2 years; range 0.1-23.7 years). Finally, 54 Contegra grafts were implanted in 53 patients; 11 patients (20.4%) had IE during a follow-up of 8.8 years (IQR 7.7 years; range 0.2-3.5 years). Survival free of IE by Kaplan-Meier for homografts was 98.7% at 5 years and 97.3% at 10 years; for Contegra 87.8% at 5 years and 77.3% at 10 years and for Melody 84.9% at 5 years (log-rank test; p<0.001). CONCLUSIONS: The Contegra conduit and Melody valved stents have a significantly higher incidence of IE than homografts. IE is a significant threat for long-term conduit function.


Assuntos
Bioprótese , Cateterismo Cardíaco/efeitos adversos , Endocardite Bacteriana/epidemiologia , Cardiopatias Congênitas/terapia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Próteses Valvulares Cardíacas , Valva Pulmonar/cirurgia , Stents , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bélgica/epidemiologia , Cateterismo Cardíaco/instrumentação , Criança , Pré-Escolar , Bases de Dados Factuais , Intervalo Livre de Doença , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/microbiologia , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/cirurgia , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Valva Pulmonar/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Centros de Atenção Terciária , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
9.
Int J Cardiol ; 175(1): 102-7, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24852832

RESUMO

BACKGROUND: Controversy remains regarding the use of covered stents in congenital heart disease (CHD). We evaluate the possibilities and safety of covered Cheatham-Platinum (CCP) stents in CHD. METHODS: Single-center retrospective CHD-database study of all CCP stents, 2003-2012. Three study groups: aortic coarctation (CoA), right ventricular outflow tract pre-stenting for percutaneous revalvulation (RVOT), and miscellaneous. Continuous data expressed as median (range). RESULTS: 114 CCP stents in 105 patients, age 16.8 years (4.2-71.2). CoA group: 54 CCP stents in 51 patients: 3/54 for aneurysm exclusion, in 51/54 covering used "prophylactically" because of increased risk for vessel tear. Overall, CCP stenting increased the coarctation diameter from 6mm (0-15) to 15 mm (10-20) (p<0.001). RVOT group: 39 CCP stents in 37 patients (34 with RVOT graft, 3 with transannular patch): the graft lumen had shrunken from nominal 21 mm (10-26) to 13 mm (5-22); with the CCP stent the RVOT was redilated to 22 mm (16-26, p<0.001 vs stenosis). Miscellaneous group: 21 CCP stents in 17 patients: closure of Fontan-circuit fenestration (n=5), restoration of superior caval vein (n=2) or pulmonary artery (n=3) patency, relief of supra-pulmonary stenosis (n=2), exclusion of aberrant pulmonary arteries (n=1), cavopulmonary conduit expansion (n=2), Blalock-Taussig shunt flow reduction (n=1), and defibrillator lead protection from sharp stents (n=1). Hybrid procedures performed in 3/17 patients. CCP stent was used as rescue treatment in 2/patients to seal iatrogenic bleeding. CONCLUSION: CCP stents can safely be applied in CHD patients. The covering allows adequate sealing of existing or expected tears, thereby increasing the safety margin with more complete dilation.


Assuntos
Materiais Revestidos Biocompatíveis/administração & dosagem , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/cirurgia , Platina/administração & dosagem , Stents/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Adulto Jovem
10.
J Thorac Cardiovasc Surg ; 145(4): 1028-1032, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22695006

RESUMO

OBJECTIVE: Postsurgical atrioventricular block may complicate surgery for congenital heart defects and is generally considered permanent when persisting longer than 14 days after surgery. In this study, we evaluate the occurrence of spontaneous late recovery of atrioventricular conduction in postsurgical chronic atrioventricular block and discuss its clinical implications. METHODS: We retrospectively reviewed all cardiac surgical procedures on cardiopulmonary bypass between January 1993 and November 2010 in subjects younger than 18 years. Patients with postsurgical advanced second- or third-degree atrioventricular block persisting longer than 14 days after surgery were included. RESULTS: Of a total of 2850 cardiac surgical procedures on cardiopulmonary bypass, 59 (2.1%) were immediately complicated by chronic postsurgical atrioventricular block of advanced second (n = 4) or third degree (n = 55). In another 6 patients (0.2%), late occurrence of chronic advanced second- (n = 3) or third-degree (n = 3) atrioventricular block, without signs of any etiology other than previous surgery, was seen 0.4 to 10 years after surgery (median, 5.7 years). Late (>2 weeks) regression to either completely normal atrioventricular conduction or asymptomatic first-degree atrioventricular block occurred 3 weeks to 7 years (median, 3.1 years) after surgery in 7 (12%) patients with immediate postsurgical chronic atrioventricular block. CONCLUSIONS: Complete recovery of atrioventricular conduction or regression to asymptomatic first-degree atrioventricular block occurred in 12% of patients with postsurgical chronic second- or third-degree atrioventricular block. To prevent unnecessary adverse side effects of chronic ventricular pacing and to prolong battery longevity, ventricular pacing should be minimized in patients with recovered normal atrioventricular conduction.


Assuntos
Bloqueio Atrioventricular/cirurgia , Sistema de Condução Cardíaco/fisiologia , Recuperação de Função Fisiológica , Adolescente , Criança , Pré-Escolar , Doença Crônica , Humanos , Lactente , Estudos Retrospectivos , Fatores de Tempo
11.
Oncogene ; 32(22): 2726-38, 2013 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-22797060

RESUMO

CD97, a member of the adhesion family of G-protein-coupled receptors (GPCRs), complexes with and potentiates lysophosphatidic acid (LPA) receptor signaling to the downstream effector RHOA. We show here that CD97 was expressed in a majority of thyroid cancers but not normal thyroid epithelium and that the level of CD97 expression was further elevated with progression to poorly differentiated and undifferentiated carcinoma. Intratumoral progression also showed that CD97 expression correlates with invasiveness and dedifferentiation. To determine the functional role of CD97, we produced a transgenic model of thyroglobulin promoter-driven CD97 expression. Transgenic CD97 in combination with Thrb(PV), an established mouse model of thyroid follicular cell carcinogenesis, significantly increased the occurrence of vascular invasion and lung metastasis. Expression of transgenic CD97 in thyroid epithelium led to elevated ERK phosphorylation and increased numbers of Ki67+ cells in developing tumors. In addition, tumor cell cultures derived from CD97 transgenic as compared with non-transgenic mice demonstrated enhanced, constitutive and LPA-stimulated ERK activation. In human thyroid cancer cell lines, CD97 depletion reduced RHO-GTP and decreased LPA-stimulated invasion but not EGF-stimulated invasion, further suggesting that CD97 influences an LPA-associated mechanism of progression. Consistent with the above, CD97 expression in human thyroid cancers correlated with LPA receptor and markers of aggressiveness including Ki67 and pAKT. This study shows an autonomous effect of CD97 on thyroid cancer progression and supports the investigation of this GPCR as a therapeutic target for these cancers.


Assuntos
Glicoproteínas de Membrana/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Ácidos Lisofosfatídicos/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Animais , Diferenciação Celular , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Antígeno Ki-67 , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Transgênicos , Invasividade Neoplásica , Fosforilação , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo
12.
J Cardiovasc Transl Res ; 5(5): 727-34, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22826102

RESUMO

Pacing postconditioning (PPC) induces cardioprotection. The aim of this study was to determine the optimal pacing algorithm and possible influence of gender and diabetes on PPC. Unprotected regional ischemia for 30 min served as negative control and classical PPC (ten cycles of 30 s left ventricular pacing alternated with 30 s right atrial pacing) as positive control. Area at risk and infarct size were determined by blue dye and triphenyltetrazolium chloride staining. For achieving protection, the minimal number of PPC cycles was seven and the minimal duration of a PPC protocol was 200 s. The protective effect of PPC was comparable in male and female hearts, but no protection could be induced by PPC in diabetic hearts. PPC can provide myocardial protection when using at least seven cycles of ventricular pacing. PPC protection is independent of gender, but sensitive to experimental diabetes.


Assuntos
Algoritmos , Estimulação Cardíaca Artificial/métodos , Diabetes Mellitus Experimental/complicações , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Aloxano , Animais , Débito Cardíaco , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/fisiopatologia , Modelos Animais de Doenças , Feminino , Masculino , Infarto do Miocárdio/complicações , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/complicações , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/patologia , Coelhos , Fatores Sexuais , Coloração e Rotulagem , Fatores de Tempo , Função Ventricular Esquerda , Pressão Ventricular
13.
Interact Cardiovasc Thorac Surg ; 15(1): 181-2, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22467005

RESUMO

An infant developed severe right heart failure early after truncal repair with a pulmonary homograft. A mechanical obstruction by narrowing could not be identified at the homograft or pulmonary arteries. However, functional obstruction was caused by an extreme windkessel effect in a massively dilated homograft that absorbed rather than transmitted the pulse wave. Effective treatment consisted of replacing the dilated homograft by a rigid aortic homograft of equal size as the initial homograft. When confronted with circulatory failure after allograft placement, the clinician should not only look for obstruction by narrowing, but also consider the windkessel phenomenon.


Assuntos
Bioprótese , Implante de Prótese Vascular/efeitos adversos , Prótese Vascular , Cardiopatias Congênitas/cirurgia , Insuficiência Cardíaca/etiologia , Hemodinâmica , Artéria Pulmonar/transplante , Tronco Arterial/cirurgia , Implante de Prótese Vascular/instrumentação , Cateterismo Cardíaco , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/fisiopatologia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/cirurgia , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Desenho de Prótese , Artéria Pulmonar/anormalidades , Artéria Pulmonar/fisiopatologia , Circulação Pulmonar , Fluxo Pulsátil , Reoperação , Índice de Gravidade de Doença , Stents , Transplante Homólogo , Resultado do Tratamento , Tronco Arterial/anormalidades , Tronco Arterial/fisiopatologia , Função Ventricular Direita
15.
Heart ; 97(24): 2051-5, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21917655

RESUMO

BACKGROUND: Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function. OBJECTIVE: In an observational multicentre study in children with isolated atrioventricular (AV) block receiving chronic ventricular pacing, the importance of the ventricular pacing site on left ventricular (LV) function was investigated. METHODS: Demographics, maternal autoantibody status and echocardiographic measurements on LV end-diastolic and end-systolic dimensions and volumes at age <18 years were retrospectively collected from patients undergoing chronic ventricular pacing (>1 year) for isolated AV block. LV fractional shortening (LVFS) and, if possible LV ejection fraction (LVEF) were calculated. Linear regression analyses were adjusted for patient characteristics. RESULTS: From 27 centres, 297 children were included, in whom pacing was applied at the RV epicardium (RVepi, n = 147), RV endocardium (RVendo, n = 113) or LV epicardium (LVepi, n = 37). LVFS was significantly affected by pacing site (p = 0.001), and not by maternal autoantibody status (p = 0.266). LVFS in LVepi (39 ± 5%) was significantly higher than in RVendo (33 ± 7%, p < 0.001) and RVepi (35 ± 8%, p = 0.001; no significant difference between RV-paced groups, p = 0.275). Subnormal LVFS (LVFS < 28%) was seen in 16/113 (14%) RVendo-paced and 21/147 (14%) RVepi-paced children, while LVFS was normal (LVFS ≥ 28%) in all LVepi-paced children (p = 0.049). These results are supported by the findings for LVEF (n = 122): LVEF was <50% in 17/69 (25%) RVendo- and in 10/35 (29%) RVepi-paced patients, while LVEF was ≥ 50% in 17/18 (94%) LVepi-paced patients. CONCLUSION: In children with isolated AV block, permanent ventricular pacing site is an important determinant of LV function, with LVFS being significantly higher with LV pacing than with RV pacing.


Assuntos
Bloqueio Atrioventricular/terapia , Estimulação Cardíaca Artificial/métodos , Função Ventricular Esquerda/fisiologia , Adolescente , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/fisiopatologia , Criança , Pré-Escolar , Ecocardiografia , Eletrocardiografia , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Volume Sistólico , Resultado do Tratamento , Disfunção Ventricular Esquerda/prevenção & controle
16.
Heart Fail Rev ; 16(3): 305-14, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21107685

RESUMO

In children with congenital or acquired complete atrioventricular (AV) block, ventricular pacing is indicated to increase heart rate. Ventricular pacing is highly beneficial in these patients, but an important side effect is that it induces abnormal electrical activation patterns. Traditionally, ventricular pacemaker leads are positioned at the right ventricle (RV). The dyssynchronous pattern of ventricular activation due to RV pacing is associated with an acute and chronic impairment of left ventricular (LV) function, structural remodeling of the LV, and increased risk of heart failure. Since the degree of pacing-induced dyssynchrony varies between the different pacing sites, 'optimal-site pacing' should aim at the prevention of mechanical dyssynchrony. Especially in children, generally paced from a very early age and having a perspective of life-long pacing, the preservation of cardiac function during chronic ventricular pacing should take high priority. In the perspective of the (patho)physiology of ventricular pacing and the importance of the sequence of activation, this paper provides an overview of the current knowledge regarding possible alternative sites for chronic ventricular pacing. Furthermore, clinical implications and practical concerns of the various pacing sites are discussed. The review concludes with recommendations for optimal-site pacing in children.


Assuntos
Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Estimulação Cardíaca Artificial/métodos , Sistema de Condução Cardíaco/fisiopatologia , Ventrículos do Coração/fisiopatologia , Disfunção Ventricular Esquerda/prevenção & controle , Bloqueio Atrioventricular/etiologia , Criança , Humanos , Disfunção Ventricular Esquerda/fisiopatologia
17.
Basic Res Cardiol ; 105(4): 523-33, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20336304

RESUMO

Brief periods of ventricular pacing during the early reperfusion phase (pacing-induced postconditioning, PPC) have been shown to reduce infarct size as measured after 2 h of reperfusion. In this study, we investigated (1) whether PPC leads to maintained reduction in infarct size, (2) whether abnormal mechanical load due to asynchronous activation is the trigger for PPC and (3) the signaling pathways that are involved in PPC. Rabbit hearts were subjected to 30 min of coronary occlusion in vivo, followed by 6 weeks of reperfusion. PPC consisted of ten 30-s intervals of left ventricular (LV) pacing, starting at reperfusion. PPC reduced infarct size (TTC staining) normalized to area at risk, from 49.0 +/- 3.3% in control to 22.9 +/- 5.7% in PPC rabbits. In isolated ejecting rabbit hearts, replacing LV pacing by biventricular pacing abolished the protective effect of PPC, whereas ten 30-s periods of high preload provided a protective effect similar to PPC. The protective effect of PPC was neither affected by the adenosine receptor blocker 8-SPT nor by the angiotensin II receptor blocker candesartan, but was abrogated by the cytoskeletal microtubule-disrupting agent colchicine. Blockers of the mitochondrial K(ATP) channel (5HD), PKC (chelerythrine) and PI3-kinase (wortmannin) all abrogated the protection provided by PPC. In the in situ pig heart, PPC reduced infarct size from 35 +/- 4 to 16 +/- 12%, a protection which was abolished by the stretch-activated channel blocker gadolinium. No infarct size reduction was achieved if PPC application was delayed by 5 min or if only five pacing cycles were used. The present study indicates that (1) PPC permanently reduces myocardial injury, (2) abnormal mechanical loading is a more likely trigger for PPC than electrical stimulation or G-coupled receptor stimulation and (3) PPC may share downstream pathways with other modes of cardioprotection.


Assuntos
Estimulação Cardíaca Artificial , Coração/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Algoritmos , Animais , Fenômenos Biomecânicos , Feminino , Hemodinâmica , Técnicas In Vitro , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/patologia , Coelhos , Suínos , Sístole
18.
Pediatr Cardiol ; 30(2): 125-32, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18704551

RESUMO

Chronic right ventricular (RV) pacing can induce structural and functional cardiac deterioration. Because animal studies showed a benefit of left ventricular (LV) over RV pacing, this study compared the effects of chronic RV and LV pacing in children. Retrospectively, echocardiographic data were evaluated from 18 healthy children (control subjects) and from children undergoing chronic epicardial RV pacing (7 RVP) or LV pacing (7 LVP). Assessment included LV end-diastolic wall thickness (LVEDWT) and end-systolic wall thickness (LVESWT) as well as LV end-diastolic diameter (LVEDD) and end-systolic diameter (LVESD). The shortening fraction and eccentricity index (LV diameter/2xLV wall thickness) were calculated as measures of LV function and eccentricity, respectively. Duration of QRS and septal posterior wall motion delay (SPWMD) were used as measures of electrical and mechanical dyssynchrony, respectively. A p value less than 0.05 determined significance. As the findings showed, LVEDD, LVESD, LVEDWT, and LVESWT were not significantly different between the groups. The shortening fraction was significantly lower in the RVP (21.7%+/-6.0%) than in the LVP (32.2%+/-5.2%) or control (29.3%+/-4.3%) children. The systolic LV eccentricity index was significantly larger in the RVP (1.8+/-0.2) than in the LVP (1.4+/-0.1) or control (1.4+/-0.2) children. The SPWMD was significantly larger in the RVP (338+/-20 ms) than in the LVP (-16+/-14 ms) or control (-5+/-35 ms) group, whereas QRS duration was similarly longer in the RVP (157+/-10 ms) and LVP (158+/-22 ms) groups compared than in the control group (69+/-7 ms). The authors conclude that LV function in children is preserved by chronic pacing at the LV lateral wall.


Assuntos
Estimulação Cardíaca Artificial , Ventrículos do Coração/patologia , Disfunção Ventricular Esquerda/terapia , Função Ventricular Esquerda , Análise de Variância , Criança , Pré-Escolar , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/inervação , Humanos , Masculino , Estudos Retrospectivos , Volume Sistólico , Ultrassonografia , Disfunção Ventricular Esquerda/diagnóstico por imagem
19.
Pacing Clin Electrophysiol ; 31 Suppl 1: S24-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18226030

RESUMO

Children with congenital or acquired atrioventricular block are provided with ventricular rate support from a pacing lead that traditionally is positioned at the right ventricular (RV) apex. However, RV apical pacing causes dyssynchronous electrical activation and left ventricular (LV) contraction, resulting in decreased LV function. Chronic RV apical pacing leads to deterioration of LV function and morphology, resulting in cardiac failure in approximately 7% of children. This review describes the pathophysiology of pacing-induced dyssynchronous LV activation and contraction, especially as a result of chronic RV apical pacing. Furthermore, this review provides an overview of the possible alternative pacing sites, such as the RV outflow tract, His-bundle, LV apex, and biventricular pacing.


Assuntos
Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Estimulação Cardíaca Artificial/métodos , Sistema de Condução Cardíaco/fisiopatologia , Ventrículos do Coração/fisiopatologia , Disfunção Ventricular Esquerda/prevenção & controle , Disfunção Ventricular Esquerda/fisiopatologia , Bloqueio Atrioventricular/congênito , Criança , Humanos , Recém-Nascido , Contração Miocárdica , Disfunção Ventricular Esquerda/congênito
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