RESUMO
AIMS: Percutaneous pulmonary valve implantation (PPVI) has proven good hemodynamic results. As infective endocarditis (IE) remains a potential complication with limited available clinical data, we reviewed our patient records to improve future strategies of IE prevention, diagnosis and treatment. METHODS: Medical records of all patients diagnosed with Melody® valve IE according to the modified Duke criteria were retrospectively analyzed in three Belgian tertiary centers. RESULTS: 23 IE episodes in 22 out of 240 patients were identified (incidence 2.4% / patient year) with a clear male predominance (86%). Median age at IE was 17.9 years (range 8.2-45.9 years) and median time from PPVI to IE was 2.4 years (range 0.7-8 years). Streptococcal species caused 10 infections (43%), followed by Staphylococcus aureus (n = 5, 22%). In 13/23 IE episodes a possible entry-point was identified (57%). IE was classified as definite in 15 (65%) and as possible in 8 (35%) cases due to limitations of imaging. Echocardiography visualized vegetations in only 10 patients. PET-CT showed positive FDG signals in 5/7 patients (71%) and intracardiac echocardiography a vegetation in 1/1 patient (100%). Eleven cases (48%) had a hemodynamically relevant pulmonary stenosis at IE presentation. Nine early and 6 late percutaneous or surgical re-interventions were performed. No IE related deaths occurred. CONCLUSIONS: IE after Melody® valve PPVI is associated with a relevant need of re-interventions. Communication to patients and physicians about risk factors is essential in prevention. The modified Duke criteria underperformed in diagnosing definite IE, but inclusion of new imaging modalities might improve diagnostic performance.
Assuntos
Endocardite Bacteriana , Endocardite , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Valva Pulmonar , Adolescente , Adulto , Criança , Endocardite/diagnóstico por imagem , Endocardite/epidemiologia , Endocardite Bacteriana/diagnóstico por imagem , Endocardite Bacteriana/epidemiologia , Próteses Valvulares Cardíacas/efeitos adversos , Humanos , Veias Jugulares , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/cirurgia , Estudos Retrospectivos , Stents , Resultado do Tratamento , Adulto JovemRESUMO
Atrial septal defects (ASDs) are the third most common type of congenital heart diseases with ostium secundum defects (ASDsII) being responsible for approximately 75% of these defects. The treatment consists of either a transcatheter closure or a surgical intervention. The transcatheter approach offers a less invasive alternative for patients who fulfill anatomical and size criteria and is therefore increasingly used as the preferred primary intervention. As general anaesthesia is sometimes contra-indicated for some patients needing ASD or PFO closure and intracardiac echocardiography (ICE) is not always readily available, alternative "supportive" techniques as hypnosis could be of interest. In our case, a relative contra-indication for general anaesthesia was pronounced due to the severely impaired pulmonary function caused by severe deformative torsional scoliosis. Over the years several reviews have been published on hypnotic analgesia used together with usual care suggesting that hypnotic analgesia is a promising non-pharmacologic adjunct treatment for ameliorating pain and surgical distress. Also, various cardiological procedures under hypnosis have already been described in literature, but this is the first time that percutaneous ASD closure under virtual reality (VR) hypnosis is mentioned in literature.
Assuntos
Septo Interatrial , Comunicação Interatrial , Hipnose , Comunicação Interatrial/diagnóstico , Comunicação Interatrial/cirurgia , HumanosRESUMO
This report describes a rare case of an aorto-cardiac fistula in a six-year-old French Warmblood mare presented with atrial fibrillation, decreased performance, ventral oedema, bounding arterial pulsation and pathological jugular venous pulse. A 2.7-cm-diameter fistula connected the right aortic sinus of Valsalva to the right atrium. Atrial fibrillation was likely due to volume overload of the right heart due to left-to-right shunting. The horse was treated by percutaneous transcatheter closure of the fistula delivered under general anaesthesia using a transarterial approach. The operation was initially successful, and clinical signs of congestive heart failure improved immediately. However, the device dislodged six days after procedure, and the general condition of the horse deteriorated quickly. A second closure attempt to deliver the occluder using a transvenous approach in the standing horse failed, and the horse was eventually euthanized. Procedural aspects and several possible risk factors for device dislodgement are discussed.
Assuntos
Átrios do Coração , Doenças dos Cavalos/cirurgia , Seio Aórtico , Fístula Vascular/veterinária , Animais , Fibrilação Atrial/etiologia , Fibrilação Atrial/veterinária , Cateterismo Cardíaco , Feminino , Cavalos , Fístula Vascular/complicações , Fístula Vascular/cirurgiaRESUMO
AIMS: The aim of this systematic review is to gain insight into the published experience on percutaneous closure of a post-infarction ventricular septal rupture (VSR). METHOD: Relevant literature was obtained by MeSH-term searches in the online search-engine PubMed. Articles published in the last 10 years were included. Further filtering was done by using search limits and individual article selection based on the aims of this systematic review. CONCLUSION: Percutaneous closure is a potential technique in a select group of patients. The presence of cardiogenic shock and closure in the acute phase after VSR diagnosis are important risk factors of mortality. Device implantation is in general successful with few procedure-related complications. Reduction of the shunt fraction has been reported frequently. This technique is a less invasive alternative to surgical treatment and should be applied on a case-by-case basis.
Assuntos
Artes Marciais/lesões , Paraganglioma/diagnóstico , Choque Cardiogênico/etiologia , Cardiomiopatia de Takotsubo/diagnóstico , Adolescente , Catecolaminas/urina , Feminino , Humanos , Imageamento por Ressonância Magnética , Paraganglioma/complicações , Paraganglioma/metabolismo , Cardiomiopatia de Takotsubo/etiologiaRESUMO
Three-dimensional rotational angiography (3D-RA) was used to image the coronary arteries of a 2(1/2)-year-old boy with pulmonary atresia intact septum and coronary fistulas. As seen in the accompanying video clips and stills, this imaging method is advantageous in depicting the coronary anatomy. Furthermore, less contrast is used for patients undergoing diagnostic coronary angiography with 3D-RA compared with biplane angiography.
Assuntos
Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Imageamento Tridimensional , Atresia Pulmonar/complicações , Fístula Vascular/diagnóstico por imagem , Pré-Escolar , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/cirurgia , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/cirurgia , Septos Cardíacos , Ventrículos do Coração/anormalidades , Humanos , Masculino , Atresia Pulmonar/cirurgia , Fístula Vascular/complicações , Fístula Vascular/cirurgiaRESUMO
With advances in surgical procedures, neuropsychological assessment after congenital heart defects and pre, peri- and/or postoperative predictors of adverse outcome has become an important focus in research. We aim to summarize neuropsychological sequelae associated with different types of congenital heart defects, critically review the methodology used in more than 20 empirical studies that were retrieved from biomedical electronic search engines, and identify possible directions for future research. Despite the lack of adequate control groups and long-term studies, there seem to be some cognitive deficits. The largest group of children with isolated congenital heart defects present with normal intellectual capacities. However, they tend to show language deficits and motor dysfunction. Although performances on memory tasks are good, unambiguous conclusions concerning their attentional and executive functioning are still lacking. Serious behavioral problems are not an issue. In addition to a detailed description of the (neuro) psychological consequences of pediatric cardiac surgery, an overview of the predictors of the cognitive defects is provided.
Assuntos
Dano Encefálico Crônico/diagnóstico , Transtornos Cognitivos/diagnóstico , Cardiopatias Congênitas/cirurgia , Testes Neuropsicológicos , Complicações Pós-Operatórias/diagnóstico , Criança , Transtornos do Comportamento Infantil/diagnóstico , Humanos , Inteligência , Fatores de Risco , Ajustamento SocialAssuntos
Cardiomiopatia Hipertrófica/cirurgia , Comunicação Interventricular/cirurgia , Próteses e Implantes , Ecocardiografia Transesofagiana , Fluoroscopia , Comunicação Interventricular/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução do Fluxo Ventricular Externo/diagnóstico por imagem , Obstrução do Fluxo Ventricular Externo/cirurgia , Pressão VentricularRESUMO
Sports camps for children with cardiac anomalies have existed for many years. However, no formal evaluation of the benefits of attending such camps has been undertaken heretofore. We assessed potential changes in the self-perceived health of children with congenital heart disease who attended a special sports camp. Thirty-one children with cardiac anomalies attended a 3-day multisports camp. Sixteen children, all of whom were 10 years or older, literate, and Dutch- or French-speaking, completed the Child Health Questionnaire (CHQ-CF87) before and after attending the camp. The scores of the children were compared with those of healthy peers by calculating mean standardized differences. After attendance at the sports camp, the children achieved significant improvements in the self-perception of their physical functioning, role functioning due to emotional problems, role functioning due to behavioral problems, mental health, and general behavior. The children's self-esteem and general behavior after the camp were significantly better than that of their healthy counterparts. We conclude that children with congenital heart disease who participate in activities at special sports camps may reap benefits in terms of their subjective health status. Although further research is needed, we recommend the participation in sport activities by children with heart defects, and more specifically their participation in sports camps.
Assuntos
Atitude Frente a Saúde , Acampamento/psicologia , Cardiopatias Congênitas/psicologia , Cardiopatias Congênitas/reabilitação , Esportes/psicologia , Adolescente , Bélgica , Criança , Feminino , Seguimentos , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Autoimagem , Autoavaliação (Psicologia)RESUMO
In a retrospective study of 32 consecutive patients undergoing a total cavopulmonary connection (TCPC), we tried to determine if the trend for decreasing age at Fontan completion and reducing the intervals between the staged procedures during the past decade was associated with a change in morbidity and outcome. In 8 patients the Fontan circulation was completed in one stage and in 24 patients an intermediate step by hemi-Fontan or bidirectional cavopulmonary anastomosis was performed before Fontan completion. Mean age at TCPC and mean interval since the previous palliation have decreased significantly during the past decade. Although major complications were significantly reduced over time the occurrence and duration of postoperative pleural effusions were not. Decreasing age as well as intervals in staged Fontan palliation have beneficial influence on major complications and outcome, without significantly affecting the duration of pleural effusions at Fontan completion.
Assuntos
Técnica de Fontan/mortalidade , Cardiopatias Congênitas/cirurgia , Cuidados Paliativos/métodos , Pré-Escolar , Feminino , Seguimentos , Cardiopatias Congênitas/epidemiologia , Humanos , Masculino , Morbidade/tendências , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Resultado do TratamentoRESUMO
BACKGROUND: Remifentanil is recommended for use in procedures with painful intraoperative stimuli but minimal postoperative pain. However, bradycardia and hypotension are known side-effects. We evaluated haemodynamic effects of i.v. glycopyrrolate during remifentanil-sevoflurane anaesthesia for cardiac catheterization of children with congenital heart disease. METHODS: Forty-five children undergoing general anaesthesia with remifentanil and sevoflurane were randomly allocated to receive either saline, glycopyrrolate 6 microg kg(-1) or glycopyrrolate 12 microg kg(-1). After induction of anaesthesia with sevoflurane, i.v. placebo or glycopyrrolate was administered. An infusion of remifentanil at the rate of 0.15 microg kg(-1) min(-1) was started, sevoflurane continued at 0.6 MAC and cisatracurium 0.2 mg kg(-1) was given. Heart rate (HR) and non-invasive arterial pressures were monitored and noted every minute for the first 10 min and then every 2.5 min for subsequent maximum of 45 min. RESULTS: Baseline HR [mean (SD)] of 117 (20) beats min(-1) decreased significantly from 12.5 min onwards after starting the remifentanil infusion in the control group [106 (18) at 12.5 min and 99 (16) beats min(-1) at 45 min]. In the groups receiving glycopyrrolate, no significant decrease in HR was noticed. Glycopyrrolate at 12 microg kg(-1) induced tachycardia between 5 and 9 min after administration. Systolic and diastolic arterial pressures decreased gradually, but there were no significant differences in the pressures between groups. CONCLUSION: I.V. glycopyrrolate 6 microg kg(-1) prevents bradycardia during general anaesthesia with remifentanil and sevoflurane for cardiac catheterization in children with congenital heart disease. Administering 12 microg kg(-1) of glycopyrrolate temporarily induces tachycardia and offers no additional advantage.
Assuntos
Bradicardia/prevenção & controle , Cateterismo Cardíaco , Glicopirrolato/uso terapêutico , Cardiopatias Congênitas/cirurgia , Piperidinas/efeitos adversos , Adjuvantes Anestésicos , Anestésicos Combinados/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Bradicardia/induzido quimicamente , Pré-Escolar , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Lactente , Cuidados Intraoperatórios/métodos , Complicações Intraoperatórias/induzido quimicamente , Complicações Intraoperatórias/prevenção & controle , Masculino , Éteres Metílicos , Estudos Prospectivos , Remifentanil , SevofluranoRESUMO
We report the case of a 7-year-old boy with a history of pulmonary atresia and intact septum who developed a fistula between the remnant of the ligated superior caval vein and the left atrium after bidirectional superior cavopulmonary (Glenn) anastomosis. The close proximity to the right pulmonary veins made closure by a standard occluder impossible. An Amplatzer vascular plug without rim enabled us to close the connection percutaneously without obstructing the pulmonary venous flow. The technique appeared to be easy, safe, and effective.
Assuntos
Embolização Terapêutica , Átrios do Coração , Derivação Cardíaca Direita/efeitos adversos , Fístula Vascular/terapia , Veia Cava Superior , Criança , Ecocardiografia , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Atresia Pulmonar/cirurgia , Circulação Pulmonar , Reoperação , Fístula Vascular/diagnóstico por imagem , Fístula Vascular/etiologia , Fístula Vascular/cirurgia , Veia Cava Superior/diagnóstico por imagemRESUMO
OBJECTIVE: To assess long term outcome of patients who underwent Mustard or Senning repair for transposition of the great arteries up to 30 years earlier. DESIGN: Retrospective review of medical records. SETTING: The six university hospitals in Belgium with paediatric cardiology departments. PATIENTS: 339 patients were reviewed, of whom 124 underwent the Mustard procedure and 215 the Senning procedure. This represents almost the entire population of patients in Belgium with either simple or complex transposition. MAIN OUTCOME MEASURES: Mortality, morbidity, functional abilities, social integration. RESULTS: Overall mortality was 24.2%. Early mortality (< or = 30 days after surgery) accounted for 16.5%, late mortality for 7.7%. Actuarial survival of early survivors at 10, 20, and 30 years after surgery was 91.7%, 88.6%, and 79.3%, respectively. Patients in the Senning cohort had a slightly better survival rate than those in the Mustard cohort (NS). Baffle obstruction occurred more often after Mustard repair (15.3%) than after the Senning procedure (1.4%). Arrhythmia-free survival did not differ between the two cohorts, but was determined by the complexity of the transposition. Survivors of the Senning cohort had better functional status, and tended to engage in more sports activities. CONCLUSIONS: The long term outcome for patients surviving the Mustard or Senning operation was favourable in terms of late mortality, morbidity, functional, and social status. Overall mortality in the Senning cohort did not differ from the Mustard group, but Senning patients had better functional status, greater participation in sports activities, and fewer baffle related problems.
Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Transposição dos Grandes Vasos/cirurgia , Adolescente , Adulto , Arritmias Cardíacas/mortalidade , Bélgica/epidemiologia , Procedimentos Cirúrgicos Cardíacos/mortalidade , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Transposição dos Grandes Vasos/mortalidade , Insuficiência da Valva Tricúspide/mortalidade , Disfunção Ventricular Esquerda/mortalidadeRESUMO
BACKGROUND AND OBJECTIVE: We conducted an open, prospective, randomized study to compare the efficacy, safety and recovery characteristics of remifentanil or propofol during monitored anaesthesia care in patients undergoing colonoscopy. METHODS: Forty patients were randomly assigned to receive either propofol (1 mg kg(-1) followed by 10 mg kg (-1) h(-1), n = 20) or remifentanil (0.5 microg kg(-1) followed by 0.2 microg kg(-1) min(-1), n = 20). The infusion rate was subsequently adapted to clinical needs. RESULTS: In the propofol group, arterial pressure and heart rate decreased significantly from the baseline. These variables remained unchanged in the remifentanil group, but hypoventilation occurred in 55% of patients. Early recovery was delayed in the propofol group (P < 0.002). Recovery of cognitive and psychomotor functions was faster in the remifentanil group. Fifteen minutes after anaesthesia, the Digit Symbol Substitution Test score was 28.6 +/- 12.8 versus 36.2 +/- 9.4 and the Trieger Dot Test score was 25.6 +/- 8.1 versus 18.7 +/- 4.1 in the propofol and remifentanil groups, respectively (both P < 0.05). Patient satisfaction, using a visual analogue scale, was higher in the propofol group (96 +/- 7 versus 77 +/- 21, P < 0.001). CONCLUSIONS: Remifentanil proved efficient in reducing pain during colonoscopy. Emergence times were shorter and the recovery of cognitive function was faster with remifentanil compared with propofol. Remifentanil provided a smoother haemodynamic profile than propofol; however, the frequent occurrence of remifentanil-induced hypoventilation requires the cautious administration of this agent.
Assuntos
Anestesia , Anestésicos Intravenosos/uso terapêutico , Colonoscopia , Monitorização Intraoperatória , Piperidinas/uso terapêutico , Propofol/uso terapêutico , Adolescente , Adulto , Idoso , Análise de Variância , Anestesia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Desempenho Psicomotor/efeitos dos fármacos , Remifentanil , Respiração/efeitos dos fármacosRESUMO
Despite providing a physiological correction, measurements of contractility using the midwall stress-velocity relationship still show evidence of an unexplained hypercontractile state in some children. We investigated if by using midwall shortening indexes, the known overestimation of contractility at low afterload could be prevented. In 12 piglets (5 or 6 weeks old), afterload was manipulated by balloon occlusion of the descending aorta and infusion of sodium nitroprusside up to 5 mg/kg/min, and left ventricular function was measured using multiple variables. The regression line between the echocardiographically derived midwall velocity of circumferential fiber shortening and end systolic wall stress differed from the regression line of the endocardial stress-velocity relationship. Although the midwall regression line was almost horizontal (or afterload independent) for end systolic wall stress values of more than 30 g/cm2, the slope was still steeper below a certain point of afterload. The increased midwall velocity of fiber shortening at low afterload is comparable to the endocardial stress-velocity relationship and could account for the pseudo-hypercontractile state found in some children.
Assuntos
Coração/fisiologia , Contração Miocárdica/fisiologia , Função Ventricular Esquerda/fisiologia , Animais , Aorta Torácica , Oclusão com Balão/métodos , Fenômenos Biomecânicos , Ecocardiografia , Feminino , Coração/efeitos dos fármacos , Masculino , Modelos Animais , Contração Miocárdica/efeitos dos fármacos , Nitroprussiato/farmacologia , Suínos , Vasodilatadores/farmacologia , Função Ventricular Esquerda/efeitos dos fármacosRESUMO
BACKGROUND: Cardiac catheterization of children with congenital heart disease is increasingly being performed under general anesthesia. Haemodynamic stability during anesthesia and fast and adequate recovery after the procedure is crucial in these patients. We performed a pilot study to evaluate hemodynamic stability when using remifentanil for anesthesia during cardiac catheterization. We also evaluated extubation times and recovery characteristics. METHODS: In a randomized, prospective, double-blind study 30 children (aged 1.5-20 months) received a continuous infusion of either 0.2 (group 0.2) or 0.3 microg/kg/min remifentanil (group 0.3) as part of a balanced anesthesia with 0.6 MAC sevoflurane. Heart rate, noninvasive arterial blood pressure, end tidal CO2 and pulse oxymetry were monitored throughout the procedure. Extubation times were noted, and recovery from anesthesia was evaluated using Aldrete scores. RESULTS: : Haemodynamic response to intubation was well blunted in both groups. No significant changes in hemodynamic variables were noted from induction of anesthesia until 10 min after intubation. From then on there was a decrease in HR and systolic arterial pressure, which remained significant throughout the procedure in both groups. Extubation times were similar in both groups: 7.3 min (2,1) in group 0.2 vs. 6.6 min (2,1) in group 0.3 (NS). The number of patients with an Aldrete score of nine or more was 14 (group 0.2) vs. 15 (group 0.3), 10 min after extubation (NS). CONCLUSION: Both dose regimens of remifentanil provided stable hemodynamic conditions during anesthesia for cardiac catheterization of children with congenital heart disease and allowed for rapid and adequate recovery.
Assuntos
Adjuvantes Anestésicos , Analgésicos Opioides , Anestesia Geral , Cateterismo Cardíaco/métodos , Cardiopatias Congênitas/complicações , Piperidinas , Adjuvantes Anestésicos/administração & dosagem , Adjuvantes Anestésicos/efeitos adversos , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/efeitos adversos , Período de Recuperação da Anestesia , Anestésicos Inalatórios , Pressão Sanguínea/efeitos dos fármacos , Criança , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Intubação Intratraqueal , Masculino , Éteres Metílicos , Monitorização Intraoperatória , Piperidinas/administração & dosagem , Piperidinas/efeitos adversos , Estudos Prospectivos , Remifentanil , SevofluranoRESUMO
After coarctectomy, local loss of distensibility is noted in addition to mild anatomic narrowing. We hypothesize that the increased Doppler peak velocities measured at the aortic isthmus in these patients partly reflect obstruction secondary to the stiff surgical scar. The hypothesis was studied in a pulsatile hydraulic model. Thirty-one patients (13.0 +/- 4.0 years of age), 10.5 +/- 4.7 years after coarctectomy by end-to-end anastomosis, were studied clinically and echocardiographically. Indexes of distensibility were calculated. The effect of isolated increased stiffness was studied in vitro with a stiff and a compliant 1:1 scale latex model of the aorta mounted in a pulsatile full-scale circulation loop. Local stiffening was obtained by a rigid ring mounted around the aorta, fitted to the dimension of the unloaded aorta. For different pressure and flow regimens, pressures and Doppler velocities were measured across the ring. Mean peak velocities at the surgical scar were 2.2 +/- 0.4 m/s. Mild anatomic stenosis was present. All distensibility indexes indicated locally increased stiffness (P <.001). In the stiff latex model, Doppler peak velocities increased from 1.89 +/- 0.04 m/s to 2.32 +/- 0.06 m/s (P <.03); in the compliant model, from 1.15 +/- 0.03 m/s to 1.79 +/- 0.05 m/s (P <.001). The increase of Doppler peak velocities depends on model compliance only and is independent of flow rate, length of the noncompliant segment, and viscosity of the perfusion fluid. Velocities do not change when semicircular stiffening is applied. We have demonstrated in vitro that isolated local nondistensibility leads to vessel narrowing during vascular distension. The relative contribution of local scar stiffness in the increase of Doppler peak velocities after coarctectomy was hereby assessed.
Assuntos
Coartação Aórtica/diagnóstico por imagem , Coartação Aórtica/fisiopatologia , Circulação Coronária , Ecocardiografia Doppler , Adolescente , Aorta/patologia , Coartação Aórtica/patologia , Coartação Aórtica/cirurgia , Velocidade do Fluxo Sanguíneo , Criança , Humanos , Modelos Cardiovasculares , Resistência VascularRESUMO
OBJECTIVE: The aim of this study is to evaluate the use of a new coating, mimicking the outer cell membrane, in paediatric cardiac surgery. METHODS: Two groups of ten patients with a body weight below 8 kg, undergoing elective cardiac operations for different congenital anomalies, were prospectively enrolled in this study. In one group the whole extracorporeal circuit, including the cannulas, was coated with phosphorylcholine (PC). In the second group the same circuit was used without coating. Platelet activation (thromboxane B2 (TXB2), beta-thromboglobulin (betaTG)), activation of the coagulation system (F1+2), leukocyte activation (CD11b/CD18) and terminal complement activation (TCC) were analyzed pre-cardiopulmonary bypass (CPB), at 15, 60 min of CPB, at the end of CPB, 20 min post CPB and at postoperative day 1 and 6. RESULTS: No statistical differences were found for F1+2 and CD11b/CD18. After onset of CPB mean levels of TCC remained stable in the PC group whereas an increase was observed in the control group. During CPB betaTG values in both groups increased to a maximum at the end of CPB. Within groups the increase in betaTG levels during CPB was statistically significant (P<0.05) from baseline in the control group starting from 60 min of CPB whereas no statistical difference was observed in the PC group. After the start of CPB TXB2 mean levels increased to 405+/-249 pg/ml in the PC group vs. 535+/-224 pg/ml in the control group. After this initial increase there was a small decline in the PC group with further increase. This was in contrast to the control group were TXB2 levels further increased up to a mean of 718+/-333 pg/ml at the end of CPB (P=0.016). CONCLUSIONS: Phosphorylcholine coating had a favourable effect on blood platelets, which is most obvious after studying the changes during cardiopulmonary bypass. A steady increase of TXB2 and betaTG was observed in the control group, whereas plateau formation was observed in the phosphorylcholine group. Clinically, this effect may contribute to reduced blood loss and less thromboembolic complications. Complement activation is lower in the coated group.
Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Ponte Cardiopulmonar/efeitos adversos , Ponte Cardiopulmonar/instrumentação , Ativação do Complemento/efeitos dos fármacos , Cardiopatias Congênitas/sangue , Cardiopatias Congênitas/cirurgia , Leucócitos/efeitos dos fármacos , Fosforilcolina/uso terapêutico , Ativação Plaquetária/efeitos dos fármacos , Antígenos CD18/sangue , Adesão Celular/efeitos dos fármacos , Feminino , Humanos , Lactente , Inflamação/sangue , Inflamação/etiologia , Antígeno de Macrófago 1/sangue , Masculino , Estudos Prospectivos , Tromboxano B2/sangue , Fatores de Tempo , beta-Tromboglobulina/metabolismoRESUMO
OBJECTIVES: Correct assessment of contractility by conventional methods during manipulation of afterload is often disappointing. To this purpose, the stress-velocity relationship offers assessment of contractility at different levels of afterload. We decided to study the influence of afterload on the nature of the stress-velocity relation. BACKGROUND: Although linear at baseline conditions in a population older than two years, data in newborns or after administration of low-dose dobutamine suggest a different nature of this relationship at low afterload. METHODS: Ten healthy piglets (five to six weeks; 11 to 13 kg) were studied. End-systolic meridional wall stress (ESWS) and rate-corrected velocity of circumferential fiber shortening (VcFc) were measured in these piglets at baseline, after balloon occlusion of the descending aorta, and at nitroprusside infusion rates of 1, 2 and 5 microg/kg/min. To eliminate inotropic influences mediated by reflex tachycardia, we subsequently studied five piglets and six adult pigs after bilateral cervical vagotomy. RESULTS: The ESWS changed from a baseline mean of 50 g/cm2 to 137 g/cm2 after balloon occlusion and to 19 g/cm2 at 5 microg/kg/min of nitroprusside. The VcFc changed from 1.19 c/s (circumference/second) to values of 0.9 c/s and 1.73 c/s, respectively. The ensuing stress-velocity regression line proved to be curvilinear instead of linear. The steeper slope at low afterload could suggest enhanced contractility compared to expected values had the relationship been linear. CONCLUSIONS: Data from young piglets and adult pigs suggest a curvilinear relationship of the stress-velocity relationship. This could probably explain some of the "hypercontractile states" encountered in conditions with low afterload.