RESUMEN
There were examined 32 injured persons, ageing (34.1 ± 1.3) yrs at average, for the brain commotion (BC). The adopted protocol SCAT-3 (Standardized Concussion Assessment Tool, 3rd ed.), DHI (Dizziness Handicap Inventory questionnaire), computer stabilography (KS) were applied for the vestibular disorders diagnosis. There was established, that in acute period of BC a dyssociation between regression of objective neurological symptoms and permanence of the BC indices occurs, what confirms a latent disorder of the balance function. Changes of basic indices of statokinesiography, including increase of the vibration amplitude enhancement in general centre of pressure in a saggital square and the BC square (235.3 ± 13.7) mm2 in a modified functional test of Romberg with the closed eyes is possible to apply as objective criteria for the BC diagnosis.
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Conmoción Encefálica/diagnóstico , Enfermedades Vestibulares/diagnóstico , Enfermedad Aguda , Adulto , Encéfalo/fisiopatología , Conmoción Encefálica/complicaciones , Conmoción Encefálica/fisiopatología , Mareo/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fotofobia/fisiopatología , Encuestas y Cuestionarios , Acúfeno/fisiopatología , Enfermedades Vestibulares/complicaciones , Enfermedades Vestibulares/fisiopatologíaRESUMEN
INTRODUCTION: Atrium and B-type natriuretic peptides (ANP and BNP) and big endothelin (ET)-1 are markers for severity of heart failure and may be used in the quality assessment of donor hearts. Elevated cardiac troponins predict early graft failure after heart transplantation. This study evaluated the effects of acute brain death (BD) on the release of ANP, BNP, big ET-1, and cardiac troponins in an animal model. MATERIALS AND METHODS: Pigs were randomized into a BD group (n=5) and a control group (n=5). In the first group, acute BD was induced, and anesthesia was stopped. In the control animals, a sham operation was performed, and anesthesia was continued. Parameters were measured at baseline and for 13 hours postoperatively. RESULTS: After acute BD, there were significant hemodynamic changes. In the control group, the BNP level was higher than in the BD group and decreased over time (P =0.016). There was no significant change in BNP release in the BD group up to 13 hours (P =0.1). ANP release remained stable over time in the control group (P =0.35) but decreased in the BD group (P =0.043). The big ET-1 levels were not different between groups. Cardiac troponin I was elevated in the BD group 5 hours after BD (P< 0.05) but remained under 1.5 mg/L throughout the study. CONCLUSION: Acute BD did not lead to an increase of BNP and ANP levels. Moreover, intact brain function seems to augment the release of natriuretic peptides from the myocardium. Further clinical evaluation of prognostic values of natriuretic peptides for the assessment of donor hearts is necessary. Cardiac troponins are a useful additional tool in the evaluation of donor hearts.
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Factor Natriurético Atrial/metabolismo , Muerte Encefálica/metabolismo , Péptido Natriurético Encefálico/metabolismo , Enfermedad Aguda , Animales , Endotelina-1/metabolismo , Femenino , Masculino , Modelos Animales , Porcinos , Troponina I/metabolismoRESUMEN
BACKGROUND: In the early post-operative period after implantation of a continuous flow left ventricular assist device (LVAD) a non-pulsatile flow occurs. We compared the post-operative time-courses of protein S-100B (S100B) and neuron-specific enolase (NSE) as biochemical markers of brain injury in patients after implantation of a continuous flow LVAD and patients receiving a pulsatile flow LVAD. METHODS: Since 1998 the continuous flow DeBakey VAD has been implanted in 8 patients at our institution. For comparison purposes, a group of 7 consecutive patients in whom a pulsatile Novacor N100 LVAD was implanted were investigated. In both groups cardiopulmonary bypass (CPB) with cardiotomy suction was used. S100B and NSE were measured in serum pre-operatively, 4 hours after CPB, and on days 1, 3, 7, and 14 after implantation of the LVAD. A neurologic examination was performed pre-operatively and post-operatively on days 3 and 14. RESULTS: No differences were found between groups in pre-operative characteristics. The analysis of variance with repeated measurements for S-100B and NSE showed significant time effects (p = 0.004, p = 0.009, respectively) but no group effects (p = 0.06, p = 0.26, respectively) and no interaction between groups and time (p = 0.12, p = 0.48, respectively). The pre-operative serum level of S100B was significantly higher (p = 0.03) in the DeBakey VAD group. The pre-operative serum level of NSE was similar in the 2 groups (p = 0.7). In both groups there was a significant increase of S100B and NSE immediately after surgery (S100B: p = 0.006, p = 0.019; NSE: p = 0.01, p = 0.001). The values returned to pre-operative levels in the DeBakey VAD group on day 1 after implantation and in the Novacor group for S100B on day 3 and NSE on day 1. Post-operatively the mean values of S100B and NSE in the DeBakey VAD group compared with the Novacor group were significantly elevated only on day 3 (p = 0.005, p = 0.023).No neurologic complications were noted in patients with a continuous flow LVAD, whereas in the pulsatile LVAD group 2 patients presented neurologic abnormalities during the study period. CONCLUSIONS: The similar course of biochemical markers of brain damage in both groups may indicate that the non-pulsatile flow in the early post-operative period does not lead to increased brain injury or permeability of the brain blood barrier.Elevated levels of S100B and NSE in the post-operative period can be used as diagnostic markers of brain injury in patients after implantation of both types of LVAD.
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Daño Encefálico Crónico/diagnóstico , Proteínas de Unión al Calcio/sangre , Corazón Auxiliar , Factores de Crecimiento Nervioso/sangre , Fosfopiruvato Hidratasa/sangre , Complicaciones Posoperatorias/diagnóstico , Flujo Pulsátil/fisiología , Proteínas S100 , Adulto , Anciano , Daño Encefálico Crónico/enzimología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/enzimología , Valor Predictivo de las Pruebas , Diseño de Prótesis , Subunidad beta de la Proteína de Unión al Calcio S100RESUMEN
AIMS: Inflammatory and immune activation and body wasting are important features of end-stage chronic heart failure. It is not known whether restoration of cardiac output by assist device implantation can improve these abnormalities. METHODS: We studied 48 patients (39 males; age 45+/-2 years) with NYHA class IV heart failure. All patients underwent ventricular assist device implantation for end-stage heart failure as a bridge to cardiac transplantation. Plasma levels of tumour necrosis factor alpha, and its receptors, interleukin-6, elastase, activated complement, and soluble CD14 receptors were measured at the time of operation and in survivors at 1 week (n=46), 40 days (n=35) and 90 days (n=26). Follow-up was for a minimum of 1 year. RESULTS: One-year survival was 35% (95% CI: 22-49%). Body mass index was the only predictor of survival (body mass index >25 (n=16); survival 63 (39-86) %; body mass index <25 (n=32); survival 22 (7.5-36) %: P=0.003). Tumour necrosis factor alpha fell from 9.66+/-1.33 pg x ml(-1) to 4.2+/-1.0 at 1 week (P=0.008), but returned to pre-operative levels at 90 days. Interleukin-6, activated complement and elastase fell progressively to 40 days, but were rising at 90 days. There was no change in tumour necrosis factor receptor. There was a gradual rise in CD14 (3.99+/-0.15 microg x ml(-1) at baseline, 5.02+/-0.39 at 90 days, P=0.006). After surgery, body weight fell from 80+/-2 to 73+/-2 kg by 1 month (P<0.001) and to 72+/-2 kg at 90 days. CONCLUSIONS: Ventricular assist device implantation results in a short-term fall in tumour necrosis factor alpha and interleukin-6, but no change in CD14 or tumour necrosis factor receptor, suggesting that the pathophysiological process resulting in inflammation was not altered by left ventricular assist device implantation. Low body mass index is related to poor outcome after assist device implantation, and no weight gain.
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Citocinas/sangre , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/terapia , Corazón Auxiliar , Peso Corporal , Proteínas del Sistema Complemento/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Alemania , Insuficiencia Cardíaca/inmunología , Insuficiencia Cardíaca/patología , Humanos , Interleucina-6/sangre , Receptores de Lipopolisacáridos/sangre , Masculino , Persona de Mediana Edad , Elastasa Pancreática/sangre , Periodo Posoperatorio , Implantación de Prótesis , Presión Esfenoidal Pulmonar , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
OBJECTIVES: We sought to investigate the relationship between the plasma concentration of brain natriuretic peptide (BNP), echocardiographic findings and the clinical outcome of patients supported with ventricular assist devices (VADs) to determine the role of BNP as a predictor for cardiac recovery. BACKGROUND: Ventricular unloading in patients with end-stage heart failure supported by VADs may lead to myocardial recovery. The BNP is produced in the myocardium in response to chronic volume overload, but the effects on it of ventricular unloading by VADs are largely unknown. METHODS: Twenty-one patients diagnosed with nonischemic cardiomyopathy and supported by VADs were evaluated for echocardiographic data and blood chemistry including BNP. They were divided into patients who died while on mechanical support (group I; n = 9), patients who were transplanted (group II; n = 8) and patients who were successfully weaned off the system and did not require transplantation (group III; n = 4). RESULTS: Brain natriuretic peptide plasma concentrations decreased significantly after initiation of mechanical circulatory support (p = 0.017). Furthermore, the changes in BNP plasma concentrations showed a faster decrease to normal levels within the first week after implantation of the VAD in patients who were weaned off the system (group III) compared to patients in group I and group II. CONCLUSIONS: This study shows that ventricular unloading with VADs decreases BNP plasma concentrations in patients who suffer from end-stage heart failure. Furthermore, we hypothesize that an early decrease of BNP plasma concentration may be indicative of recovery of ventricular function during mechanical circulatory support.
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Insuficiencia Cardíaca/terapia , Corazón Auxiliar , Péptido Natriurético Encefálico/sangre , Adolescente , Adulto , Preescolar , Ecocardiografía Transesofágica , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Tasa de SupervivenciaRESUMEN
From July 1996 to March 2000, 391 patients with intraoperative cardiac low-output syndrome who underwent surgery with heart-lung bypass and had an intra-aortic balloon pump (IABP) implanted were analyzed in a prospective study. Of these 391 patients, 153 (39%) were operated on in an emergency situation, and 238 (61%) patients had elective surgeries. The perioperative mortality was 34% (133 patients). Clinical parameters were analyzed 1 hour after IABP support began. Statistical multivariate analysis showed that patients with an adrenaline requirement higher than 0.5 microg/kg/min, a left atrial pressure higher than 15 mmHg, output of less than 100 mL/hour, and mixed venous saturation (SvQ2) of less than 60% had poor outcomes. Using this data, we developed an IABP score to predict survival early after IABP implantation in cardiac surgery. We conclude that the success or failure of perioperative IABP support can be predicted early after implantation of the balloon pump. In patients with low-output syndrome despite IABP support, implantation of a ventricular assist system should be considered.
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Gasto Cardíaco Bajo/fisiopatología , Gasto Cardíaco Bajo/terapia , Hemodinámica , Contrapulsador Intraaórtico , Anciano , Puente Cardiopulmonar , Femenino , Humanos , Contrapulsador Intraaórtico/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Estudios Prospectivos , Tasa de Supervivencia , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: To date, donor-specific markers to predict outcome after heart transplantation (HTx) are unknown. Increased procalcitonin (PCT) levels have been found in infectious inflammation with systemic reactions and/or poor organ perfusion but have not been studied in heart donors. We evaluated PCT as a predictor of early graft failure-related mortality after HTx. METHODS AND RESULTS: PCT and C-reactive protein (CRP) serum concentrations were measured in samples collected immediately before pericardium opening from 81 consecutive brain-dead multiple-organ donors. Donors for high-urgency-status recipients (n=2) were excluded from analysis. The remaining donors were retrospectively divided into 2 groups: donors for recipients who died within 30 days after HTx, after an early graft failure (group II, n=8), and all other donors (group I, n=71). No differences in donor and recipient demographic characteristics were found between groups. Areas under the receiver operating characteristic curves for graft failure-related mortality were 0.71 for PCT and 0.64 for CRP. A PCT value >2 ng/mL as a predictor of graft failure-related mortality had a specificity of 95.8% and sensitivity of 50.0%. The odds ratio for graft failure-related mortality for recipients of hearts from donors with PCT levels >2 ng/mL was 22.7 (unadjusted, 95% CI 3.7 to 137.8, P=0.0007) and 43.8 (after adjustment for prespecified potential confounders, 95% CI 1.4 to 1361.0, P=0.031). CONCLUSIONS: A PCT level >2 ng/mL in a cardiac donor at the time of explantation appears to predict early graft failure-related mortality.
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Calcitonina/sangre , Rechazo de Injerto/mortalidad , Trasplante de Corazón , Infecciones/diagnóstico , Precursores de Proteínas/sangre , Donantes de Tejidos , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Péptido Relacionado con Gen de Calcitonina , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Trasplante de Corazón/inmunología , Humanos , Infecciones/sangre , Oportunidad Relativa , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad , Tasa de SupervivenciaRESUMEN
A 62-year-old man with end-stage ischemic cardiomyopathy and left ventricular function of 20% was evaluated for heart transplantation. Cardiac catheterization revealed proximal occlusion of the dominant right coronary artery (RCA) with collateral blood flow and significant stenosis in the distal part, but no significant re-occlusions of the stented left coronary artery and no significant stenosis of the left circumflex artery. When the patient became catecholamine dependent, Novacor left ventricular assist device (LVAD) implantation, as a bridge to transplantation, was considered and the patient operated upon. To avoid ischemic right heart failure after LVAD implantation, a concomitant re-vascularization of the distal RCA was performed. The post-operative course was uneventful. Five weeks later, a control angiogram showed the patent bypass graft. The distal stenosis of the RCA was treated successfully with dilation and stent implantation. The patient is presently in stable condition on LVAD and awaits transplantation as an outpatient.
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Cardiomiopatías/cirugía , Puente de Arteria Coronaria , Enfermedad Coronaria/cirugía , Trasplante de Corazón , Corazón Auxiliar , Disfunción Ventricular Izquierda/cirugía , Angioplastia Coronaria con Balón , Cardiomiopatías/diagnóstico por imagen , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Stents , Resultado del Tratamiento , Disfunción Ventricular Izquierda/diagnóstico por imagenRESUMEN
BACKGROUND: Cardiac troponin I and T (cTnI and cTnT) are sensitive and specific markers of myocardial damage. We evaluated them for the selection of heart donors and as predictors of early graft failure after heart transplantation. METHODS: cTnI, cTnT, myoglobin, and creatine kinase (CK) levels and its isoenzyme MB (CKMB) activity and mass were measured in serum samples immediately before opening the pericardium from 126 consecutive brain-dead multi-organ donors over 10 years of age inspected by our harvesting team. Donors with serum creatinine >2.0 mg/dL (n=6) were excluded from the analysis. Donors for high-urgency status recipients (n=2) were also excluded. The remaining donors were retrospectively divided into three groups: group I (n=68), grafts with good function; group II (n=11), grafts with impaired function; and group III (n=39), grafts not accepted for transplantation. RESULTS: No differences in donor and recipient characteristics were found among the groups. The mean values of cTnI (0.36+/-0.88 microg/L, 4.45+/-3.28 microg/L, and 3.02+/-7.88 micog/L, respectively) and cTnT (0.016+/-0.029 microg/L, 0.134+/-0.114 microg/L, and 0.123+/-0.245 microg/L, respectively) were lower in group I when compared with groups II or III (cTnI: P<0.0001, P=0.018; cTnT: P<0.0001, P=0.012). The cTnI value was higher in group II compared with group III (P=0.023). The cTnT values were similar in groups II and III. A cTnI value >1.6 microg/L as a predictor of early graft failure had a specificity of 94%, and a cTnT value of >0.1 microg/L had a specificity of 99%. The odds ratio for the development of acute graft failure after heart transplantation was 42.7 for donors with cTnI >1.6 microg/L and 56.9 for donors with cTnT >0.1 microg/L. No differences of myoglobin, CKMB activity, or CKMB/CK ratio were found among the groups. CONCLUSIONS: Significantly higher cTnI and cTnT values were found in peripheral blood at the time of explantation in donors of hearts with subsequently impaired graft function and in not accepted donors. cTnI and cTnT are useful as additional parameters for heart donor selection.
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Rechazo de Injerto , Trasplante de Corazón , Miocardio/metabolismo , Selección de Paciente , Donantes de Tejidos , Troponina I/metabolismo , Troponina T/metabolismo , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Pronóstico , Curva ROC , Factores de Tiempo , Troponina I/sangre , Troponina T/sangreRESUMEN
To date, one approach to tissue engineering has been to develop in vitro conditions to ultimately fabricate functional cardiovascular structures prior to final implantation. In our current experiment, we developed a new pulsatile flow system that provides biochemical and biomechanical signals to regulate autologous patch-tissue development in vitro. The newly developed patch bioreactor is made of Plexiglas and is completely transparent (Mediport Kardiotechnik, Berlin). The bioreactor is connected to an air-driven respirator pump, and the cell culture medium continuously circulates through a closed-loop system. We thus developed a closed-loop, perfused bioreactor for long-term patch-tissue conditioning, which combines continuous, pulsatile perfusion and mechanical stimulation by periodically stretching the tissue-engineered patch constructs. By adjusting the stroke volume, the stroke rate, and the inspiration/expiration time of the ventilator, it allows various pulsatile flows and different levels of pressure. The whole system is a highly isolated cell culture setting, which provides a high level of sterility, gas supply, and fits into a standard humidified incubator. The bioreactor can be sterilized by ethylene oxide and assembled with a standard screwdriver. Our newly developed bioreactor provides optimal biomechanical and biodynamical stimuli for controlled tissue development and in vitro conditioning of an autologous tissue-engineered patch.
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Reactores Biológicos , Ingeniería de Tejidos/instrumentación , Materiales Biocompatibles , Procedimientos Quirúrgicos Cardíacos , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Humanos , Ingeniería de Tejidos/métodosRESUMEN
Mechanical ventricular assist devices (VAD) have become an accepted therapy for the support of patients in severe heart failure. With the devices presently available, the incidence of thromboembolic complications is high. Since November 1998, we have used the DeBakey VAD (MicroMed, Inc., Woodlands, TX). To detect the effect of this VAD on the appearance of microthrombi or bubbles from cavitation, we measured Microembolic Signals (MES) with transcranial Doppler in patients after the implantation of the DeBakey VAD. Transcranial Doppler studies were performed with the MULTI-DOP X4 device with two 2 MHz probes (for the left and right middle cranial arteries [MCA]) in five patients preoperatively and during 10 weeks after VAD implantation. Both MCAs were monitored simultaneously for 60 minutes in 10 sessions in each patient. The detection and analysis of MES was performed in accordance with the technique and criteria described by the international consensus group. No MES were noted during the study period in four patients. In one patient with preoperatively noted MES the prevalence of MES postoperatively was 50%. The high speed rotating impeller of the DeBakey VAD did not produce any detectable microthrombi or bubbles from cavitation effects.
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Embolia/diagnóstico por imagen , Embolia/epidemiología , Insuficiencia Cardíaca/terapia , Corazón Auxiliar/efectos adversos , Ultrasonografía Doppler Transcraneal , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/epidemiología , Prevalencia , Diseño de Prótesis , Flujo PulsátilRESUMEN
The implantation of a ventricular assist device (VAD) is associated with a stimulation of the inflammatory system. We compared changes in the inflammatory response after implantation of a pulsatile Novacor left (L) VAD and the axial flow MicroMed DeBakey VAD. Six consecutive patients after implantation of a Novacor LVAD (NC) and six patients after implantation of a MicroMed DeBakey VAD (MD) were included in the investigation. Patients received LVADs for medically non treatable end-stage heart failure. Tumor necrosis factor alpha (TNF), C3a, C5a, interleukin 6 (IL-6), and neutrophil elastase were measured twice a week over a period of 3 months after implantation of the device. All tests were performed with an enzyme-linked immunosorbent assay. There was no significant difference in the clinical course of the two groups. All inflammatory parameters were elevated in both groups during the entire period of the investigation. There was no difference in TNF, polynuclear leukocyte elastase, or C3a levels between the two groups; however, IL-6 (NC: 23.6+/-37.6 pg/ml vs. MD: 63+/-114 pg/ml, p < 0.001) and C5a (NC: 708+/-352 microg/L vs. MD: 1,745+/-1,305 microg/L, p < 0.001) were increased significantly more in patients following implantation of the axial flow MicroMed DeBakey VAD. Compared with the pulsatile Novacor device, the implantation of the axial flow MicroMed DeBakey LVAD seems to be associated with an increased stimulation of one part of the inflammatory system. Further investigations are necessary for evaluation of the pathophysiologic mechanism and clinical implications of these findings.
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Activación de Complemento , Insuficiencia Cardíaca/cirugía , Insuficiencia Cardíaca/terapia , Corazón Auxiliar/efectos adversos , Adulto , Coagulación Sanguínea/inmunología , Complemento C3a/metabolismo , Complemento C5a/metabolismo , Femenino , Insuficiencia Cardíaca/inmunología , Humanos , Interleucina-6/metabolismo , Elastasa de Leucocito/metabolismo , Masculino , Persona de Mediana Edad , Implantación de Prótesis , Flujo Pulsátil , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
BACKGROUND: Central shunt (CS) is frequently used to treat diminished pulmonary blood flow in newborns. We analyzed the impact of CS on the growth of the pulmonary arteries (PAs). METHODS: Twenty-two consecutive newborns underwent a CS procedure. In 15 newborns the preoperative angiograms and angiograms taken before undergoing anatomic or hemodynamic correction procedures were analyzed. The patients were divided retrospectively into two groups by the size of the PA in the preoperative angiogram: group I, patients with PAs more than 4 mm (n = 10), group II, PAs 4 mm or less (n = 5). To compare the development of the PAs in the groups, the Nakata index, McGoon ratio, and lower lobe indices were calculated from angiograms. RESULTS: The indices were significantly higher in group I before CS, but no differences was found between the groups before anatomic or hemodynamic correction. The postoperative Nakata indices and the McGoon ratios in the groups were higher when compared with preoperative values (group I, p = 0.037 and p = 0.013; group II, p = 0.043 and p = 0.043, respectively). The significant increase of the lower lobe indices only in group II (p = 0.043) suggests faster growth of the PA in this group. CONCLUSIONS: Optimal diameters of the CS promote growth of the PAs, which was confirmed by the increased Nakata and McGoon indices. The benefit in smaller PAs is greater.
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Aorta/cirugía , Arteria Pulmonar/crecimiento & desarrollo , Arteria Pulmonar/cirugía , Anastomosis Quirúrgica , Femenino , Humanos , Recién Nacido , Masculino , Estudios Retrospectivos , Procedimientos Quirúrgicos VascularesRESUMEN
BACKGROUND: Changes in renal blood flow are considered to play a significant role in the induction and maintenance of kidney failure, but are difficult to monitor with currently available techniques. The objective was to validate renal flow measurements with Doppler guidewires and to apply this technique to assess dose and time dependency of the renal vascular effects of norepinephrine (NE). METHODS: In 10 anesthetized pigs, flow velocity in renal arteries (FVart) and veins (FVvein) and volumetric renal blood flow (VBF) were measured before and after intravenous bolus application of incremental doses of NE (2 to 200 microg). RESULTS: FVart curves exactly reflected the changes in VBF. Beat-to-beat analysis revealed a strong linear correlation over a mean VBF range of less than 0.05 to 0.35 L/min (median correlation coefficient with FVart, r = 0.998), and significant but less close relationships were also found between VBF and FVvein. Ten seconds after the administration of 200 microg NE, FVart dropped from 71 to 6 cm/sec and was 90% reversible after 48 seconds. Similarly, the renal vascular resistance temporarily rose from 988 to 13711 mm Hg. min/L. In contrast, NE-induced increases in systemic vascular resistance were on average a maximum of 1.5-fold but persisted for more than 60 seconds. CONCLUSIONS: Doppler flow measurements in the renal artery provide an excellent surrogate of volumetric blood flow, which may be useful for continuous monitoring of renal hemodynamics. The renal vasculature is more sensitive when compared with the systemic vasculature, but also appears to evoke more efficient counter-regulatory mechanisms in response to NE.
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Arteria Renal/diagnóstico por imagen , Arteria Renal/fisiología , Venas Renales/diagnóstico por imagen , Venas Renales/fisiología , Ultrasonografía Doppler , Ultrasonografía Intervencional , Animales , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Volumen Sanguíneo/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Inyecciones Intravenosas , Norepinefrina/farmacología , Factores de Tiempo , Resistencia Vascular/efectos de los fármacos , Vasoconstrictores/farmacologíaRESUMEN
OBJECTIVE: Coating of ventricular assist devices (VADs) with heparin improves the biocompatibility and may reduce the need for systemic anticoagulation. However, heparins are associated with the risk of formation of heparin/platelet factor 4 antibodies (HPF4/A) and the development of heparin-associated thromboemboli. We analyzed the occurrence of HPF4/A and thromboembolism in patients with heparin-coated and noncoated VADs. METHODS: One hundred patients were enrolled in the investigation. Fifty-seven received a heparin-coated (group 1) and 43 a noncoated (group 2) VAD. HPF4/A testing was performed before and 2 and 12 weeks after implantation by the heparin platelet factor 4 enzyme-linked immunosorbent assay. RESULTS: There was no significant difference in the occurrence of HPF4/A in the 2 groups (P =.102). Before the operation, 21 of the patients in group 1 had positive test responses and 25 in group 2. No patient had HPF4/A after termination of systemic heparinization. In group 1 there was no significant difference in the incidence of recurrent pump thromboses in patients who had positive test responses for HPF4/A (n = 11) when compared with those who had negative test responses (n = 9, P =.89). Twenty-one patients had HPF/A but no thromboembolism. However, all 22 patients who had thromboembolism had HPF4/A. CONCLUSIONS: Heparin coating of the VAD surface does not enhance the occurrence of HPF4/A-associated immunologic or thrombogenic reactions. However, the presence of these antibodies is strongly associated with an increased risk of thromboembolism in patients with a VAD.
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Anticoagulantes/inmunología , Fibrinolíticos/inmunología , Corazón Auxiliar , Heparina/inmunología , Factor Plaquetario 4/inmunología , Tromboembolia/etiología , Adolescente , Adulto , Anticoagulantes/administración & dosificación , Femenino , Fibrinolíticos/administración & dosificación , Corazón Auxiliar/efectos adversos , Heparina/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Tromboembolia/inmunologíaRESUMEN
BACKGROUND: Ventricular assist devices (VADs) are an accepted therapy for patients with end-stage heart failure. The implantable devices that are available produce a pulsatile flow and are very large. In 6 patients, beginning in November 1998, we started to use the continuous-flow implantable DeBakey VAD device, which weighs 93 g. To detect the flow in peripheral vessels, we measured transcranial Doppler signals in patients after implantation. METHODS AND RESULTS: Transcranial Doppler studies were performed with the MULTI-DOP X4 device with two 2-MHz probes (for the middle cranial arteries) in 4 patients for up to 12 weeks twice weekly after implantation. The blood velocity was measured, and the pulsation index (PI) calculated. The measured pump flow and rotations per minute were registered. The preoperative echocardiographic assessment values were compared with those acquired 6 weeks after implantation. The PI increased continually in all patients after VAD implantation, left ventricular (LV) ejection fraction did not improve, but right ventricular (RV) ejection fraction after implantation improved compared with preoperative values. The LV end-diastolic diameter after implantation decreased between 11% and 46% intraindividually. There was no correlation between PI and blood pressure or, except in 1 patient, between PI and blood flow through the VAD. CONCLUSIONS: The DeBakey VAD unloads the LV, which leads to a decrease in LV end-diastolic LV diameter and to the restoration of RV function. The unloaded LV and partially recovered RV provide a nearly physiological pulsatile flow despite the continuous flow of the VAD. Pulsatility is independent of peripheral vascular resistance. The first clinical experience with the DeBakey VAD was positive and has resulted in its continued use.
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Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/cirugía , Corazón Auxiliar , Flujo Pulsátil , Adulto , Velocidad del Flujo Sanguíneo , Circulación Cerebrovascular , Ecocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Arteria Cerebral Media/diagnóstico por imagen , Resultado del Tratamiento , Ultrasonografía Doppler Transcraneal , Función Ventricular IzquierdaRESUMEN
BACKGROUND: Donor heart shortage has necessitated the expansion of the donor pool by the use of older hearts. PATIENTS AND METHODS: In a 13-year period, 1,070 heart transplants were performed in 1,035 adults at the German Heart Institute Berlin. We divided the patients into 3 groups: Group I, donor age <35 years (n = 524); Group II, donor age 35 to 50 years (n = 379); Group III, donor age >50 years (n = 167). We analyzed post-operative mortality (up to 30 days), cumulative survival rates, cardiac dependent morbidity, and changes in the left/right ventricular ejection fraction as well as freedom from cytomegalovirus infection and freedom from acute rejection episodes grade >/= 2 (International Society for Heart and Lung Transplantation). We also calculated the rate of cardiac interventions per patient in the groups. RESULTS: Recipients in Group III were significantly older, compared with Groups I and II. The post-operative mortality was 16.8% in Group I, 29.8% in Group II, and 23.4% in Group III. The differences were significant (p = 0. 00001) between Group I and Group II. The long-term cumulative survival rates were significantly better in Group I when compared with Groups II and III (p < 0.00001, p = 0.014), but it did not differ between Groups II and III (p = 0.18). However, cardiac morbidity in Groups I and II was significantly lower when compared with Group III (p = 0.0009, p = 0.037). Mean left and right ventricular ejection fraction was >55% and did not significantly change in groups for up to 10 years. Freedom from cytomegalovirus infection was not significantly different between Groups II and III (p = 0.09). Significantly fewer percutaneous transluminal coronary angioplasties were performed in Group I, but comparable numbers were carried out in Groups II and III (p = 0.53). For retransplantation a similar situation occurred. CONCLUSION: We did not find significant differences in the mid-term follow-up between patients who received hearts from 35- to 50-year-old donors and from those who had received hearts from donors >50 years, despite increased cardiac morbidity in Group III. Close monitoring of the coronary situation after heart transplantation and expanded indications for revascularization in Group III makes heart transplantation with older hearts a suitable option to save the lives of patients in end-stage heart failure.