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1.
Environ Sci Technol ; 50(13): 7066-73, 2016 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-27244483

RESUMO

Atmospheric nuclear weapons testing (NWT) resulted in the injection of plutonium (Pu) into the atmosphere and subsequent global deposition. We present a new method for continuous semiquantitative measurement of (239)Pu in ice cores, which was used to develop annual records of fallout from NWT in ten ice cores from Greenland and Antarctica. The (239)Pu was measured directly using an inductively coupled plasma-sector field mass spectrometer, thereby reducing analysis time and increasing depth-resolution with respect to previous methods. To validate this method, we compared our one year averaged results to published (239)Pu records and other records of NWT. The (239)Pu profiles from the Arctic ice cores reflected global trends in NWT and were in agreement with discrete Pu profiles from lower latitude ice cores. The (239)Pu measurements in the Antarctic ice cores tracked low latitude NWT, consistent with previously published discrete records from Antarctica. Advantages of the continuous (239)Pu measurement method are (1) reduced sample preparation and analysis time; (2) no requirement for additional ice samples for NWT fallout determinations; (3) measurements are exactly coregistered with all other chemical, elemental, isotopic, and gas measurements from the continuous analytical system; and (4) the long half-life means the (239)Pu record is stable through time.


Assuntos
Gelo , Plutônio , Atmosfera , Meia-Vida , Armas Nucleares
2.
Opt Express ; 22(1): 737-48, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24515033

RESUMO

An open converged metro-access network approach allows for sharing optical layer resources like fibers and optical spectrum among different services and operators. We demonstrated experimentally the feasibility of such a concept by the simultaneous operation of multiple services showing different modulation formats and multiplexing techniques. Flexible access nodes are implemented including semiconductor optical amplifiers to create a transparent and reconfigurable optical ring network. The impact of cascaded optical amplifiers on the signal quality is studied along the ring. In addition, the influence of high power rival signals in the same waveband and in the same fiber is analyzed.

3.
Rehabilitation (Stuttg) ; 53(5): 321-6, 2014 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-24363218

RESUMO

AIM OF THE STUDY: Regular physical activity has found to be a strategy to increase exercise capacity in patients with chronic heart failure (CHF). Next to endurance training also electromyostimulation (EMS) of thigh and gluteal muscles results in an increased capacity in CHF patients. EMS therapy was either done by stimulating 8 major muscle groups involving also trunk and arm muscles (extended electromyostimulation (exEMS)) in comparison to EMS therapy limited to gluteal and leg muscles (limEMS). METHODS: 31 individuals completed the EMS training program. Stable CHF patients (NYHA class II-III) received either exEMS (18 patients, 11 males, mean age 59.8±13.8 years) or limEMS (13 patients, 10 males, 63.6±9.4 years). Training was performed for 10 weeks twice weekly for 20 min, the level of daily activity remained unchanged. Effects on exercise capacity, left ventricular function (EF - ejection fraction) and QoL (quality of life) were evaluated. RESULTS: QoL was found to be improved in all domains of the SF-36 questionnaire. In the exEMS group there was a significant improvement in the domain physical functioning (54.09±29.9 to 75.45±15.6, p=0.48) and emotional role (63.63±45.8 to 93.93±20.1 p=0.048). LimEMS group showed significant improvement in the domain vitality (37.5±6.9 to 52.8±12.5, p=0.02).There was a significant increase of oxygen uptake at aerobic threshold in all groups (exEMS: +29.6%, p<0.001; limEMS +17.5%, p<0.001). EF -increased from 36.94±8.6 to 42.36±9.1% (+14.7%, p=0.003) in the exEMS group (limEMS 37.7±3.6 to 40.3±5.9% [+6.9%, p=0.18]). CONCLUSION: EMS contributes to an improved quality of life and can improve oxygen uptake and EF in CHF. It may be an alternative therapy in CHF patients who are otherwise unable to undertake conventional forms of exercise training.


Assuntos
Terapia por Estimulação Elétrica/métodos , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/reabilitação , Consumo de Oxigênio , Condicionamento Físico Humano/métodos , Qualidade de Vida/psicologia , Volume Sistólico , Doença Crônica , Terapia por Estimulação Elétrica/psicologia , Feminino , Insuficiência Cardíaca/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Condicionamento Físico Humano/psicologia , Aptidão Física , Resultado do Tratamento
5.
Artigo em Inglês | MEDLINE | ID: mdl-22765201

RESUMO

In consequent continuation of previous described studies, pre-characterised silicone materials were assessed for chemical and physical parameters during long-term usage. In a particular case study silicone moulds were used in a commercial pizza bakery on a daily basis up to 1700 times. Migration behaviour, uptake of fat, the amount of volatiles and extractables, as well as physical properties (elongation, tensile strength) were monitored for the whole period. The main question was whether a significant degradation or even breakdown of the silicone elastomer could take place yielding enhanced migration of dimethyl siloxanes. Oligomeric dimethyl siloxanes are reaction side-products of the polymerisation process and despite their origin as so-called non-intentionally added substances (NIAS) were found to be the by far most dominating constituents of the overall migration. Furthermore, the influence of long-term thermal stress on the functionality of the elastomer was proven. Migration into food was determined by (1)H-NMR and was found to decrease during the experiment from values between 11 and 18 mg kg(-1) to levels below the limit of detection (LOD < 1 mg kg(-1)). No formation of migrating siloxanes beside the initial amount in the new, unused moulds could be observed. The loss of extractable siloxanes of the used compared with the new moulds was compensated by an uptake of fat and other lipophilic food constituents. The release of volatile organic compounds (VOC) decreased from 0.44% for the new moulds to 0.14% for the longest used ones (about 1700 individual uses; the corresponding summarised baking time was approximately 400 h at 180°C). GC-MS analysis of evaporating volatile compounds showed only cyclic oligomers for the new moulds but exclusively incorporated food components for the heavily used moulds. The physical properties of the silicone moulds remained almost constant during the experiment; no limitations in function due to the repeated thermal stress were observed. Similar results were obtained for baby teats under household conditions of use: a 100 times repeated simulated use in contact with milk followed by subsequent microwave sterilisation did not influence the function or mechanical properties. Because milk is only a weak extracting agent no significant changes in the amount of extractable siloxanes between new and used teats could was seen. Again an uptake of fat was seen and the amount of VOC decreased from 0.26% to 0.17%.


Assuntos
Silicones , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Compostos Orgânicos Voláteis/análise
6.
Thorac Cardiovasc Surg ; 55(3): 163-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17410501

RESUMO

BACKGROUND: Several risk factors for early mortality after intra-aortic balloon pump (IABP) implantation have been described. METHODS: We performed a retrospective analysis in 120 patients receiving peri- or postoperative IABP support. Univariate and multivariate analyses were carried out to assess variables potentially influencing 30-day mortality in order to develop a risk score for the prognosis of survival and for the decision on optimal patient-specific treatment. RESULTS: The 4 parameters (mean arterial pressure, adrenaline dose, central venous pressure, and blood lactate concentrations) at 6 hours of IABP use were independently related to 30-day mortality. They were used to develop a risk score (0 - 4 points). With this score, patients who scored 3 or 4 points had no probability of surviving, whereas patients with a score of zero had a probability of 84.4 %. A prospectively screened cohort of 145 patients confirmed the reliability of our risk score. CONCLUSIONS: Our data demonstrate that a score can predict 30-day mortality in patients with IABP implantation. Such a score can be useful to find out whether or not ECMO/VAD implantation is necessary.


Assuntos
Balão Intra-Aórtico/mortalidade , Procedimentos Cirúrgicos Torácicos/mortalidade , Idoso , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Análise Multivariada , Assistência Perioperatória , Complicações Pós-Operatórias/mortalidade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
7.
J Cardiovasc Surg (Torino) ; 46(1): 51-4, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15758878

RESUMO

AIM: Mitral valve procedure after previous coronary artery bypass grafting (CABG) with functioning internal mammary artery (IMA) grafts has high risk. Especially, internal mammary artery grafts injury may be fatal. The anterolateral right thoracotomy affords easy access to the right atrium with minimal dissection, and minimizes the risk of injury to the IMA grafts. We reviewed our operative technique and outcome after mitral valve procedure after previous CABG with functioning IMA grafts. METHODS: Thirteen patients (11 male and 2 female, mean age of 67.7+/-8.5 years, range 54 to 80 years) underwent mitral valve replacement after previous CABG with functioning IMA grafts from march 1993 to september 2002. The mean interval between the previous CABG and the mitral valve procedure was 3.8 years (range 9 months to 8 years). Four patients had simultaneous mitral valve procedures at initial CABG (2 repairs and 2 replacements). The operation has performed through the anterolateral right thoracotomy, under ventricular fibrillation with moderate hypothermia and without cardioplesia. RESULTS: Mitral valve repair was performed in 3 patients, mitral valve replacement in 10 patients. The mean coronary bypass time was 69.1+/-16.2 min (range 45 to 98 min). The operation time was 159.3+/-29.4 min (range 120 to 219 min). Intensive care unit stay days was 1.9+/-1.6 days (range 1 to 5 days). Peak CK/CK-MB values were 555.1+/-290.4 IU/16.6+/-10.7 IU (range 176 to 924 IU/7 to 44 IU). Peak troponin I value was 9.5+/-5.2 pg/mL (range 4 to 17.8 pg/mL). There was no IMA injury and no early death. Other complications were newly arrhythmia in 3 patients, renal insufficiency in 1 patient, reoperation for bleeding in 1 patient. CONCLUSIONS: Anterolateral right thoracotomy approach, ventricular fibrillation with moderate hypothermia without cardioplesia were a safe and good method for mitral valve operation after previous CABG with functioning IMA graft.


Assuntos
Implante de Prótese de Valva Cardíaca , Anastomose de Artéria Torácica Interna-Coronária , Valva Mitral , Toracotomia/métodos , Idoso , Feminino , Humanos , Hipotermia Induzida , Cuidados Intraoperatórios , Masculino , Valva Mitral/cirurgia
8.
Nature ; 431(7005): 147-51, 2004 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-15356621

RESUMO

Two deep ice cores from central Greenland, drilled in the 1990s, have played a key role in climate reconstructions of the Northern Hemisphere, but the oldest sections of the cores were disturbed in chronology owing to ice folding near the bedrock. Here we present an undisturbed climate record from a North Greenland ice core, which extends back to 123,000 years before the present, within the last interglacial period. The oxygen isotopes in the ice imply that climate was stable during the last interglacial period, with temperatures 5 degrees C warmer than today. We find unexpectedly large temperature differences between our new record from northern Greenland and the undisturbed sections of the cores from central Greenland, suggesting that the extent of ice in the Northern Hemisphere modulated the latitudinal temperature gradients in Greenland. This record shows a slow decline in temperatures that marked the initiation of the last glacial period. Our record reveals a hitherto unrecognized warm period initiated by an abrupt climate warming about 115,000 years ago, before glacial conditions were fully developed. This event does not appear to have an immediate Antarctic counterpart, suggesting that the climate see-saw between the hemispheres (which dominated the last glacial period) was not operating at this time.

9.
Z Kardiol ; 93(9): 664-70, 2004 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-15365733

RESUMO

Despite enormous progress concerning material and design, patients with artificial heart valves still face a considerable risk of serious complications (e. g. hemorrhage, thromboemboli, redos) which sum up to 5-20% within the first 10 postoperative years depending on type and position of the implanted prosthetic valve. Nowadays technical defects of mechanical valves are negligible and relevant complications are most frequently the consequence of inappropriate oral anticoagulation therapy. To avoid these complications a strict control of both the anticoagulation therapy and the functional integrity of the prosthetic valve is mandatory. Therefore with the aim of risk minimization the patient should be enabled to cooperate by means of methods which are easy to handle in his everyday environment. We present a reliable method for early detection of prosthetic valve dysfunction which can be applied daily with minimal effort by the patient himself.


Assuntos
Próteses Valvulares Cardíacas/efeitos adversos , Monitorização Fisiológica/instrumentação , Falha de Prótese , Trombose/diagnóstico , Administração Oral , Animais , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Testes de Coagulação Sanguínea , Implante de Prótese de Valva Cardíaca , Humanos , Fatores de Risco , Autocuidado/instrumentação , Suínos , Trombose/tratamento farmacológico , Fatores de Tempo
10.
Thorac Cardiovasc Surg ; 52(4): 211-17, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15293158

RESUMO

PURPOSE: The purpose of this study was to investigate whether: 1. sound phenomena may be used to detect prosthetic valve dysfunction; 2. clinical and experimental data permit conclusions about alterations in the functional state of mechanical valves; 3. patients can record and pass on signals via Internet. METHODS: 1. We implanted bi-leaflet valves in pigs. By gradually influencing the motion of the tilting discs prosthetic dysfunction could be generated. 2. Thrombosis and lysis of bi-leaflet valves was studied in sheep. This process was documented using echocardiography and acoustically by the Fast Fourier Transformation. 3. Thirty devices were set up and handed out to patients following mechanical valve replacement. All patients regularly sent data to the hospital via Internet, regardless of their location at the time. The data were evaluated by comparing them with the reference file. RESULTS: Animal experiments proved that changes in prosthetic function led to a significant change in sound phenomena. In contrast to echocardiography alterations at an early stage (onset of thrombosis) could be reliably verified. The sensitivity was greater than in echo-control analysis. All patients regularly recorded and passed on their signals. Surveys revealed high acceptance and easy handling of the devices. CONCLUSIONS: Online registration of sound phenomena seems to be suitable for the detection of changes in prosthetic function. This led to the development of the first hand-held device for home monitoring of valve function. Registration of flow, frequency spectrum, and ECG envisaged at the next level opens up potential applications for Internet-based, remote monitoring of cardiac patients.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Monitorização Ambulatorial/instrumentação , Fonocardiografia/métodos , Animais , Ruídos Cardíacos , Humanos , Internet , Modelos Animais , Modelos Cardiovasculares , Ovinos , Suínos
11.
J Card Surg ; 18(6): 519-23, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14992103

RESUMO

Aortic dissection after coronary artery bypass grafting (CABG) is a rare but potentially fatal complication. The aim of this study was to identify the reasons. Between 1991 and 2000 in our institution CABG was performed on 22,732 patients. In the same time interval 12 (0.5 degree/00) patients presented with an aortic dissection after previous CABG. Age: 59.1 +/- 5.9 years, gender: 10/2, only Stanford A dissections, 4 chronic and 8 acute dissections, mortality: 3, all acute. 2 died of cardiac complications (left heart failure), 1 of other complications (gastrointestinal ischemia). The time interval between CABG and dissection was 2.5 +/- 3.6 years. Two dissections were intraoperative, another 5 were within the first year; the longest time interval was 10 years. In 5 cases the entry originated from a central anastomosis, 1 originated from the aortic cannulation site, and 1 from the site of the cross clamping. In 5 cases the entry was not directly related to the previous operation (1 was located in close proximity to the left coronary ostium, 2 between aortic valve annulus and the coronary ostia and 2 between the distal coronary arteries in the ascending aorta). Pathological changes of the aorta were not described at the time of CABG; only in 1 case a mild aortic regurgitation and dilatation (47 mm) at the time of the first operation was described. As our results suggest an aortic dissection presenting after CABG must be considered to be a rare complication of the previous operation. Considering the severity of this complication satisfying results can be achieved.


Assuntos
Aneurisma Aórtico/etiologia , Dissecção Aórtica/etiologia , Ponte de Artéria Coronária/efeitos adversos , Estudos Retrospectivos , Humanos , Complicações Intraoperatórias
12.
J Thorac Cardiovasc Surg ; 119(4 Pt 1): 764-73, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10733767

RESUMO

OBJECTIVE: Controversy continues about the treatment of patients with a concomitant occlusive disease of the coronary and carotid arteries. Our operative strategy in these patients is to do simultaneous carotid endarterectomy and myocardial revascularization in conjunction with cardiopulmonary bypass with mild hypothermia. We report our experience with this kind of one-stage procedure and its retrospective long-term results. METHODS: From February 1985 to September 1998, 340 patients underwent simultaneous carotid endarterectomy and myocardial revascularization. The average age of the patients was 65.3 years; 45.6% were neurologically symptomatic, and 44.4% had bilateral carotid stenosis. The indication for carotid endarterectomy was lumen diameter reduction of more than 75%, angiographic signs of thrombogenic endovascular morphology, or both. Carotid endarterectomy was performed in conjunction with cardiopulmonary bypass with mild hypothermia, hemodilution, systemic heparinization, and controlled hemodynamics under pulsatile perfusion for additional cerebral protection. RESULTS: There were 16 perioperative neurologic complications (4.7%), 11 permanent deficits (3.2%), and 9 cardiac complications (2.6%). Early mortality was 2.6% (SE 0.8%): 2 patients had a stroke and 2 had a myocardial infarction. The 5-year survival was 78.9% (SE 2.6%), and freedom from ipsilateral stroke and cardiac event were 93.2% (SE 1.5%) and 87.5% (SE 2.1%), respectively. The predictor for early death was age over 70 years, and predictors for late death were age over 70 years, previous myocardial infarction, previous stroke, and bilateral carotid stenosis of greater than 90%. CONCLUSION: On the basis of our long-term results, we believe that simultaneous carotid endarterectomy and myocardial revascularization in conjunction with cardiopulmonary bypass is a method safe enough to prefer its routine use with acceptable low operative risk and satisfactory long-term morbidity.


Assuntos
Ponte Cardiopulmonar , Ponte de Artéria Coronária , Endarterectomia das Carótidas , Idoso , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/mortalidade , Endarterectomia das Carótidas/efeitos adversos , Endarterectomia das Carótidas/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/etiologia
13.
J Mol Cell Cardiol ; 29(11): 2989-96, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9405174

RESUMO

Dynamic cardiomyoplasty, a method to support ventricular function by the chronically stimulated latissimus dorsi muscle wrapped around the heart is accompanied by a loss of mass and force of the transplanted muscle. These effects and the fast-to-slow transformation of the muscle could be possibly influenced by the additional administration of anabolic steroids. In this study, the left latissimus dorsi muscles of 12 sheep were electrically conditioned (group A). In 12 other animals (group B), stimulation was combined with the administration of metenolone (100 mg/week). Biopsies were taken from the right and left muscles at the beginning and after 6 and 12 weeks of treatment, frozen and cross-sectioned. The muscle fibre type composition was studied enzymhistochemically (SDH-staining and Myosin-ATPase-reaction) and immunocytochemically (using antibodies against different myosin heavy chains, MHC). Furthermore, the expression of different MHC isoforms was investigated electrophoretically. The untreated latissimus dorsi muscle contains 20% type I fibres expressing slow MHC and 80% type II fibres expressing fast MHC. After 6 weeks, the respective fibre type composition was 42 and 58% (group A) and 80 and 20% (group B). After 12 weeks, the percentage of the type I fibres rose in group A to 59% and in group B to 98%. In accordance with these morphological results, the MHC pattern determined electrophoretically showed a corresponding shift from the fast to the slow isoform. Therefore, the administration of metenolone avoids severe muscle atrophy, and improves and accelerates fast to slow fibre type conversion necessary for successful cardiomyoplasty.


Assuntos
Cardiomioplastia/métodos , Metenolona/análogos & derivados , Fibras Musculares de Contração Rápida/efeitos dos fármacos , Fibras Musculares de Contração Lenta/efeitos dos fármacos , Cadeias Pesadas de Miosina/análise , Animais , Feminino , Imuno-Histoquímica , Metenolona/farmacologia , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Lenta/metabolismo , Ovinos , Estimulação Química
15.
Ann Thorac Surg ; 59(4): 961-9; discussion 969-70, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7695425

RESUMO

The loss of force and mass in the conditioned latissimus dorsi muscle are principal reasons for the poor improvement in hemodynamic functioning attained by cardiomyoplasty. Using 24 sheep, we investigated the effect of anabolic steroids on the hemodynamic, histologic, and myophysiologic characteristics in the setting of cardiomyoplasty. In 12 of the animals (group A), the latissimus dorsi muscles were electrically conditioned with an Itrel pulse generator; in the remaining 12 animals (group B), the electrical conditioning was combined with the administration of an anabolic hormone (metenolone; 100 mg/week). The hemodynamic measurements were performed during isolated perfusion of the subclavian artery (maintenance of pressure in the muscles), while all other circulation variables were held at the exact and reproducible value of zero by inducing ventricular fibrillation. Maximum force and muscle mass showed a significant increase in group B (maximum force: group A, 4.23 +/- 0.55 kp, and group B, 6.0 +/- 3.14 kp; muscle mass: group A, +11.07% +/- 1.06%, and group B, +79.9% +/- 40.8%). The ratio of type I to type II fibers after 12 weeks was 65.2% to 34.8% in group A and 96.7% to 3.3% in group B, as opposed to 19.9% to 80.1% in the control group. No side effects of the anabolic steroids were observed during the experiment. In the hemodynamic studies, we were able to demonstrate a further significant increase in the left ventricular pressure, fractional fiber shortening value, ejection fraction, stroke volume, cardiac output, and stroke work when using conditioned latissimus dorsi muscles that were additionally treated with metenolone.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anabolizantes/farmacologia , Cardiomioplastia , Contração Muscular/efeitos dos fármacos , Fibras Musculares de Contração Rápida/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Pressão Ventricular/fisiologia , Animais , Estimulação Elétrica , Feminino , Metenolona/farmacologia , Contração Muscular/fisiologia , Fibras Musculares de Contração Rápida/fisiologia , Fibras Musculares de Contração Lenta/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Tamanho do Órgão , Ovinos , Volume Sistólico/fisiologia
16.
Eur J Cardiothorac Surg ; 8(4): 214-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8031566

RESUMO

In 12 sheep the left latissimus dorsi muscles (LD) were conditioned by chronic electrostimulation with a pulse generator (Itrel, Medtronic). Six animals (group B) received a weekly intramuscular injection of an anabolic steroid (Metenolon). After 14 weeks the contraction parameters of the left LDs (group A and B) and right LDs (control group) were investigated. The increase in weight of the conditioned LDs was 11.07% (+/- 1.06%) in group A and 79.97% (+/- 40.8; P < 0.05) in group B. The force capacity under stimulation patterns which were just tetanic was 1.15 kp in group A and 4.13 kp in group B (P < 0.05); under supramaximal stimulation patterns it was 4.23 kp (A) and 6.0 kp (B) (P = ns). The force time relation (dF/dt) was 6.7 kp/s for the left LDs in group A versus 16.4 kp/s for the right LDs (P < 0.01); in group B it was 5.13 kp/s for the left LDs versus 15.8 kp/s for the control muscles (P < 0.05). The maximal force (Fmax) per 100 g muscle weight did not differ significantly (A: 2.42 kp/100 g; B: 2.52 kp/100 g). In conclusion, the LD muscles which were subjected to both anabolic therapy and electrical stimulation showed a significant increase in their force capacity due to an enormous increase in mass. Fibre type transformation was complete only in group B. No fibre deterioration was observable in either group. No anabolic side effects were detected in the animals. With the use of anabolic steroids, therefore, a clearer direct increase in contractility on the left ventricle should be expected ("squeezing" theory), as well as a contribution to reduction in wall tension and myocardial oxygen consumption, respectively, according to Laplace's Law (via the considerable increase in thickness).


Assuntos
Anabolizantes/farmacologia , Circulação Assistida/métodos , Terapia por Estimulação Elétrica , Metenolona/farmacologia , Contração Muscular/efeitos dos fármacos , Músculos/efeitos dos fármacos , Animais , Feminino , Ventrículos do Coração , Contração Muscular/fisiologia , Músculos/fisiologia , Ovinos , Retalhos Cirúrgicos
17.
Z Gesamte Inn Med ; 48(10): 497-501, 1993 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-8256469

RESUMO

Between 1/1986 and 5/1992 a total of 5283 surgical procedures involving extracorporal circulation were performed at our clinic, including 44 patients who underwent a total of 54 operations for acute endocarditis. On the basis of a retrospective study, this paper presents the pre-operative findings and the results of surgery in relation to the duration of the case history. Pathogenic microorganisms were successfully grown from the blood cultures of 63.6% (n = 31) of the patients. Among these microorganisms were viridans streptococci (n = 12), coagulase-negative staphylococci (n = 5), staph. aureus (n = 5), beta-haemolytic streptococci (n = 2) as well as combined infections (n = 2) and miscellanea. Preoperatively, 38 patients were in NYHA stage III or IV. Surgery resulted in an average improvement of 1.6 NYHA classes from NYHA 3.3 to NYHA 1.7. The total-mortality rate was n = 13; early mortality was n = 3. The mean follow-up period was 3.9 years (minimum 5 weeks, maximum 6.4 years). The time elapsed between initial clinical manifestation of the disease and operation had a significant influence on mortality and on the prevalence of complications. Patients who died of endocarditis had a significantly longer case history (p < 0.05). The prognosis was poorer, according to our data, if the case history extended over more than 80 days. Our results demonstrate clearly the necessity for such patients to be referred to a heart surgeon without delay.


Assuntos
Endocardite Bacteriana/cirurgia , Infecções Estafilocócicas/cirurgia , Infecções Estreptocócicas/cirurgia , Adolescente , Adulto , Idoso , Criança , Endocardite Bacteriana/mortalidade , Endocardite Bacteriana/patologia , Feminino , Seguimentos , Próteses Valvulares Cardíacas , Valvas Cardíacas/patologia , Valvas Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/patologia , Estudos Retrospectivos , Infecções Estafilocócicas/mortalidade , Infecções Estafilocócicas/patologia , Infecções Estreptocócicas/mortalidade , Infecções Estreptocócicas/patologia , Taxa de Sobrevida , Fatores de Tempo
18.
Z Gesamte Inn Med ; 48(8): 404-5, 1993 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-8379224

RESUMO

We report on a case of isolated pulmonary valve endocarditis caused by coagulase-negative staphylococci 22 years after total correction of a pentalogy of Fallot. The M-mode and two-dimensional echocardiographic findings are presented, and the patient's clinical progress is described. An overview of the literature shows isolated endocarditis of the pulmonary valve to be an exceptionally rare occurrence. 6 months postoperatively, the patient has not been experiencing a relapse and is now in NYHA stage I.


Assuntos
Endocardite Bacteriana/cirurgia , Próteses Valvulares Cardíacas , Complicações Pós-Operatórias/cirurgia , Valva Pulmonar/cirurgia , Infecções Estafilocócicas/cirurgia , Tetralogia de Fallot/cirurgia , Adulto , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/cirurgia , Ecocardiografia , Endocardite Bacteriana/diagnóstico por imagem , Humanos , Masculino , Complicações Pós-Operatórias/diagnóstico por imagem , Valva Pulmonar/diagnóstico por imagem , Insuficiência da Valva Pulmonar/diagnóstico por imagem , Insuficiência da Valva Pulmonar/cirurgia , Infecções Estafilocócicas/diagnóstico por imagem
19.
Z Gesamte Inn Med ; 47(10): 460-5, 1992 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-1441657

RESUMO

The value of transaortal subvalvular myectomy after Morrow remains unclarified. We therefore analysed our results with HOCM with particular attention to the operation risk and the longterm results. 56 patients were treated at the Leipzig Heart Centre between January 1984 and August 1990 using the transaortic myectomy. In 16 patients an additional mitral valve replacement or -reconstruction was required. In 14 patients, other combined operations (aortic valve replacement, aortocoronary bypass) were indicated. In the postoperative observation period (up to 7 years; 141 patient-years; mean follow-up 4.2 yrs) detailed information was obtained at regular intervals about subjective complaints, ECG changes, left ventricular functional parameters and the weight of the heart muscle mass were recorded. The myectomy resulted in an alteration of the NYHA-class from 3.1 to 1.3 postoperatively (p < 0.05). The ventriculo-aortal pressure gradient reduced in the group myectomy (group I) from 69.2 +/- 5.2 to 23.3 +/- 2.7 mmHg postoperatively. In the myectomy+mitral valve repair group (group II) the intracavitary pressure gradient was even reduced to 11.7 +/- 2.2 Torr (p < 0.05). The Sokolov-Lyon-Index was 3.7 +/- 0.19 mV preoperatively and went down to 2.9 +/- 0.16 mV. The heart muscle mass decreased from 680 g to a postoperative value of 430 g (p < 0.05). The relation of BAR and calcium channel density of 0.5 +/- 0.1 in HOCM versus 0.9 +/- 0.08 in a control group (n = 6) proves the increased number of calcium channels in HOCM.


Assuntos
Cardiomiopatia Hipertrófica/cirurgia , Ecocardiografia Doppler , Ecocardiografia , Hemodinâmica/fisiologia , Complicações Pós-Operatórias/diagnóstico por imagem , Adolescente , Adulto , Idoso , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Velocidade do Fluxo Sanguíneo/fisiologia , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/mortalidade , Terapia Combinada , Ponte de Artéria Coronária , Feminino , Seguimentos , Próteses Valvulares Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Complicações Pós-Operatórias/mortalidade , Taxa de Sobrevida
20.
Thorac Cardiovasc Surg ; 40(2): 65-9, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1631874

RESUMO

UNLABELLED: Between 1/84 and 6/91 56 patients were treated for hypertrophic obstructive cardiomyopathy (HOCM): the Morrow technique alone was performed on 40 patients (group 1), in 16 patients (group 2) an additional replacement (n = 13) or reconstruction (n = 3) of the mitral valve was indicated. In a total of 14 cases coronary artery bypass grafting and aortic valve replacement was performed in addition. Postoperatively (mean follow-up 4.2 yrs, 141 patient-years) left-ventricular diastolic and systolic function parameters, heart muscle mass, ECG findings, and symptomatology were recorded and the ratios of beta-adrenoreceptor density to density of the calcium channel were measured. RESULTS: Pressure gradient decreased from 69.2 +/- 5.2 (group 1) and 75.1 +/- 4.8 (group 2) to 23.3 +/- 2.7 and 11.7 +/- 2.2 mmHg postoperatively. Likewise Sokolow-Lyon index decreased from 3.5 +/- 0.2/3.7 +/- 0.2 to 2.9 +/- 0.2/2.8 +/- 0.3. The quotient time-to-peak-velocity/left-ventricular-ejection-time decreased significantly in group 2 from 58.6 +/- 6.3 to 41.9 +/- 5.8 (p less than 0.05). The heart muscle mass, determined echocardiographically, decreased from 680g to 430g (p less than 0.05). Isovolumetric tension time, isovolumetric relaxation time, and E/A ratio at rest and after stress showed typical characteristics. Ca(++)-channel density was clearly raised in all patients, with no differences between the two groups being observable. We conclude from our results: The most marked improvements in clinical and left-ventricular functional parameters were experienced by patients in group 2 (myectomy+MVR).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Valva Aórtica/cirurgia , Cardiomiopatia Hipertrófica/cirurgia , Valva Mitral/cirurgia , Adolescente , Adulto , Idoso , Cardiomiopatia Hipertrófica/mortalidade , Cardiomiopatia Hipertrófica/fisiopatologia , Seguimentos , Hemodinâmica , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade
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