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1.
Cancer ; 91(2): 302-10, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11180075

RESUMO

BACKGROUND: In Hodgkin disease (HD), accurate assessment of the extent of disease is essential because it provides the basis for different treatment strategies. In addition to conventional imaging methods (CIM), positron emission tomography with fluorine-18-fluorodeoxyglucose (FDG-PET) may permit reliable differentiation between lymphoma and nonmalignant tissue and thus improve determination of the stage of the disease. The aim of the current study was to assess the clinical value of FDG-PET for primary staging, treatment monitoring, and assessment in a suspected case of recurrent HD. METHODS: Eighty-one patients with HD underwent 106 FDG-PET studies using a dedicated whole body PET ring scanner. In 25 patients PET was part of the primary staging, 63 PET studies were undertaken for treatment monitoring after the completion of treatment, and in 18 patients PET was performed in cases of suspected recurrence of HD. PET scans were compared with CIM and verified histologically and/or by follow-up evaluation (mean follow-up duration, 20.4 months). RESULTS: With regard to primary staging, in a patient to patient analysis, both PET scans and CIM were positive (i.e., showed pathologic foci indicative of HD) in 24 of 25 cases. In a staging-relevant lesion to lesion analysis, accuracy in the determination of the stage of disease was 96% for PET versus 56% for CIM. PET led to a lower stage classification in 28% and a higher stage classification in 12% of cases, compared with the stage assumed with CIM. With regard to treatment monitoring, PET showed an accuracy of 91% compared with 62% for CIM. The negative predictive value of PET was 96%. With regard to suspected recurrence, PET findings were true-positive in 10 of 12 PET scans and true-negative in 5 of 6 PET scans, resulting in accuracy of 83%, which compares favorably with the accuracy rate of 56% for CIM. CONCLUSIONS: It may be concluded that FDG-PET is capable of determining the stage of HD with great accuracy and is capable of correctly detecting manifestations of HD in treatment monitoring and cases of suspected recurrence, in which CIM occasionally result in equivocal findings. The results of the current study suggest that FDG-PET should become a routine tool in the staging/restaging of HD.


Assuntos
Fluordesoxiglucose F18 , Doença de Hodgkin/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão/métodos , Adulto , Feminino , Doença de Hodgkin/patologia , Humanos , Masculino , Radiografia , Estudos Retrospectivos
2.
Nucl Med Commun ; 19(6): 535-45, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10234657

RESUMO

The aim of this study was to test the feasibility of the direct measurement of global and regional metabolic wall thickening with 18F-FDG-gated positron emission tomography (PET) in patients with coronary artery disease (CAD). Based on non-invasive (ECG, echocardiography) and invasive [cineventriculography (CVG), coronary angiography] investigations, 12 patients with CAD underwent gated metabolic PET studies with 18F-FDG. Myocardial wall thickening and wall motion analysis from short-axis horizontal and vertical long-axis slices were studied. PET-derived global ejection fraction correlated with CVG-derived global ejection fraction (r = 0.75). Forty-eight of 72 segments investigated were normal (66.7%); 24 of 72 segments were abnormal (33.3%), of which 10 (41.7%) were considered to be hibernating. Four segments were classified as partially fibrotic (16.7%) and 10 (41.7%) as entirely scar-like. Gated PET (8 gates, tail drop corrected) allows quantification of global and regional ejection fraction to detect metabolic wall thickening in left ventricular segments with dyskinesia on CVG due to critical CAD stenoses. By improving data analysis methods, our approach may enhance the detection of viable, hibernating myocardium before revascularization.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Fluordesoxiglucose F18 , Coração/diagnóstico por imagem , Miocárdio Atordoado/diagnóstico por imagem , Compostos Radiofarmacêuticos , Fibrose , Fluordesoxiglucose F18/farmacocinética , Imagem do Acúmulo Cardíaco de Comporta , Humanos , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio Atordoado/patologia , Miocárdio/patologia , Compostos Radiofarmacêuticos/farmacocinética , Valores de Referência , Tecnécio Tc 99m Sestamibi , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão
3.
Nucl Med Commun ; 18(9): 811-22, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9352546

RESUMO

A number of neurodegenerative diseases have been evaluated with 123I-iodobenzamide (123I-IBZM) dopamine receptor scintigraphy, including Parkinson's disease. Differential diagnosis is based on the semi-quantitative determination of striatal uptake in the basal ganglia. Seven procedures for calculating basal ganglia uptake were compared and checked statistically in (1) 28 previously untreated de novo parkinsonian patients before and (2) 14 patients after (mean of 9 months) commencement of anti-Parkinson medication. Of the 21 hemi-parkinsonian patients, 16 demonstrated increased uptake contralaterally (mean right-to-left difference = 8%, sensitivity = 76%) using the most robust uptake procedure. The difference in uptake between the affected and contralateral sides (mean = 6%) was significant (P = 0.02). The mean (+/- S.D.) basal ganglia/frontal cortex (BG/FC) ratio was 1.55 +/- 0.14 (attenuation-corrected). Attenuation correction did not affect the relative ratio of basal ganglia uptake (P = 0.01). The anti-Parkinson medication did not result in any significant changes in the BG/FC ratio at follow-up, but responders could be differentiated from non-responders based on initial uptake (mean BG/FC ratio of 1.58 and 1.39 respectively). We conclude that 123I-IBZM can be used routinely to identify which Parkinson patients will benefit from dopaminergic medication.


Assuntos
Benzamidas , Doença de Parkinson/diagnóstico por imagem , Pirrolidinas , Receptores de Dopamina D2/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Idoso , Antiparkinsonianos/uso terapêutico , Gânglios da Base/diagnóstico por imagem , Gânglios da Base/metabolismo , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/metabolismo , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Doença de Parkinson/terapia , Tomografia Computadorizada de Emissão , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos
4.
Psychiatry Res ; 75(2): 67-74, 1997 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-9351489

RESUMO

The possible predictive value of regional cerebral perfusion patterns with respect to the response to partial sleep deprivation (PSD) was evaluated in 15 major depressive patients (mean age = 54.9 years, mean Hamilton depression score = 21.6). Patients were studied with single photon emission computed tomography with technetium-99 m-D,L-hexamethyl-propylene amine oxime. Scans were performed on the morning before and after (at 08.00 h) PSD. Responders to PSD had significantly higher perfusion in the right orbitofrontal cortex than did non-responders before PSD. Multiple regression analysis indicated that right orbitofrontal/basal cingulate perfusion (r = -0.77, P < 0.001) before PSD, and left inferior temporal perfusion (r = 0.59, P = 0.01) after PSD, were fairly accurate predictors of change in Hamilton depression scores. Thus, it appears that the orbitofrontal cortex and the cingulate are involved in PSD and may serve as predictors of therapeutic response.


Assuntos
Transtorno Bipolar/terapia , Encéfalo/irrigação sanguínea , Transtorno Depressivo Maior/terapia , Privação do Sono/fisiologia , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/fisiopatologia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/fisiopatologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/fisiologia , Resultado do Tratamento
5.
Nuklearmedizin ; 34(4): 161-4, 1995 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-7675647

RESUMO

A 50-y-old male patient with prostate cancer showed two suspicious lesions in bone scintigrams. They were assessed to be bone metastases by biopsy of the os ilium. After i.v. injection of 99mTc-HMDP a probe-guided localization permitted optimal surgical treatment. A bone metastasis in the os ilium was confirmed. The intraoperative detection with a hand-held gamma probe permitted accurate and complete excision of the tumour; the bone defect could thus be reduced to a minimum.


Assuntos
Neoplasias Ósseas/secundário , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Cintilografia/instrumentação , Medronato de Tecnécio Tc 99m/análogos & derivados , Neoplasias Ósseas/diagnóstico por imagem , Osso e Ossos/diagnóstico por imagem , Raios gama , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , Cintilografia/métodos , Reprodutibilidade dos Testes
6.
Nucl Med Commun ; 16(8): 675-82, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7491180

RESUMO

Dual-isotope studies using 123I and 201Tl allow the assessment of sympathetic reinnervation in patients following heart transplantation. 123I-meta-iodobenzyl guanidine (123I-MIBG) serves as a tracer of the integrity of the sympathetic nervous system. 201Tl is used for landmarking to allow better delineation of the myocardium due to faint 123I-MIBG accumulation in heart transplants. The aim of this study was to evaluate the influence of parameters such as crossover, attenuation and the 123I/201TI activity ratio on the assessment of the myocardial 123I-MIBG uptake ratio using phantom and patient studies. Crossover was calculated using the ratio: 201TI counts in the 123I energy window/201Tl counts in the 201Tl window. Phantom studies were performed using a rectangular phantom (RP) and a cardiac phantom (CP). The mean crossover from the 201Tl to the 123I energy window was 11.48% (RP) and 11.13% (CP). Depending on attenuation in water (depth of water 0-5 cm), crossover increased from 10.92 to 15.85% (RP) and from 11.05 to 15.79% (CP). In order to confirm that the experimental crossover results were equivalent to those obtained in patient studies, 15 patients underwent myocardial scintigraphy. After injection of 201Tl, a simultaneous dual-window acquisition was performed to assess crossover from the 201Tl to the 123I window. The mean crossover was 15.35%, as high as the crossover assessed in phantom studies, taking into account attenuation and scatter caused by the chest wall. In order to reduce 201Tl crossover, the 123I activities were six times as high as the 201Tl activities.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Transplante de Coração , Coração/diagnóstico por imagem , Coração/inervação , Radioisótopos do Iodo , Iodobenzenos , Regeneração Nervosa , Imagens de Fantasmas , Radioisótopos de Tálio , 3-Iodobenzilguanidina , Câmaras gama , Transplante de Coração/fisiologia , Radioisótopos do Iodo/farmacocinética , Iodobenzenos/farmacocinética , Cintilografia , Reprodutibilidade dos Testes , Radioisótopos de Tálio/farmacocinética
7.
Eur J Nucl Med ; 22(5): 443-52, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7641753

RESUMO

Cardiac transplantation entails surgical disruption of the sympathetic nerve fibres from their somata, resulting in sympathetic denervation. In order to investigate the occurrence of sympathetic re-innervation, neurotransmitter scintigraphy using the norepinephrine analogue iodine-123 metaiodobenzylguanidine (MIBG) was performed in 15 patients 2-69 months after transplantation. In addition, norepinephrine content and immunohistochemical reactions of antibodies to Schwann cell-associated S100 protein, to neuron-specific enolase (NSE) and to norepinephrine were examined in 34 endomyocardial biopsies of 29 patients 1-88 months after transplantation. Anterobasal 123I-MIBG uptake indicating partial sympathetic re-innervation could be shown in 40% of the scintigraphically investigated patients 37-69 months after transplantation. In immunohistochemical studies 83% of the patients investigated 1-72 months after transplantation showed nerve fibres in their biopsies but not positive reaction to norepinephrine. Significant norepinephrine content indicating re-innervation could not be detected in any biopsy. It was concluded that in spite of the lack of norepinephrine content there seemed to be immunohistological and scintigraphic evidence of sympathetic re-innervation. An explanation for this contradictory finding may be the reduced or missing norepinephrine storage ability compared to the restored uptake ability of regenerated sympathetic nerve fibres.


Assuntos
Transplante de Coração/diagnóstico por imagem , Coração/inervação , Radioisótopos do Iodo , Iodobenzenos , Norepinefrina/análise , Sistema Nervoso Simpático/diagnóstico por imagem , Simpatolíticos , Radioisótopos de Tálio , 3-Iodobenzilguanidina , Biópsia , Feminino , Transplante de Coração/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/química , Fosfopiruvato Hidratase/análise , Cintilografia , Proteínas S100/análise , Sistema Nervoso Simpático/fisiologia
8.
Gastroenterology ; 108(4): 1048-55, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7698571

RESUMO

BACKGROUND/AIMS: The current standard for gastric emptying studies are radioactive isotope methods. [13C]breath tests have been developed as a nonradioactive alternative. The aim of this study was to validate a [13C]acetate breath test as a measure of gastric emptying of the liquid phase both in liquid and semisolid test meals by simultaneous radioscintigraphy. METHODS: Thirty-five patients with dyspeptic symptoms and 20 healthy volunteers were tested using a semisolid oatmeal or a liquid test meal. Both test meals were labeled by 150 mg sodium [13C]acetate and (in patients) by 45 MBq 99mTc-albumin colloid. Half-time of gastric emptying was calculated after curve fitting of the 13C exhalation to a modified power exponential function. 99mTc-albumin emptying was measured by conventional radioscintigraphy. RESULTS: The half-emptying times for the [13C]acetate breath test closely correlated to those measured by radioscintigraphy both for semisolids (r = 0.87) and liquids (r = 0.95). The time of maximum 13CO2 exhalation was itself a reliable parameter compared with the half-emptying times obtained by scintigraphy (r = 0.85 for semisolids; r = 0.94 for liquids). CONCLUSIONS: The [13C]acetate breath test is a reliable and noninvasive tool for the analysis of gastric emptying rates of liquid phases without radiation exposure.


Assuntos
Acetatos , Testes Respiratórios , Radioisótopos de Carbono , Esvaziamento Gástrico , Acetatos/análise , Adulto , Idoso , Testes Respiratórios/métodos , Radioisótopos de Carbono/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Agregado de Albumina Marcado com Tecnécio Tc 99m
9.
Nucl Med Commun ; 15(8): 593-603, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7970441

RESUMO

The aim of this study was to evaluate and validate a new quantification method for 99Tcm-sestamibi single photon emission computed tomographic (SPECT) myocardial imaging based on a four-slice analysis method and to check the functional results of percutaneous transluminal coronary angioplasty (PTCA). Using the calculated pathological area of the scintigram as an index for myocardial ischaemia, the overall sensitivity was 81-90% and the overall specificity was 74-98%. Analysis of variance of the repeated measurements revealed good reproducibility (coefficient of variation 8.4%). A significant correlation was found between the size of the exercise-induced perfusion defects and the degree of coronary stenosis. The comparison of radionuclide ventriculography and the perfusion image in 27 patients revealed a good correlation between the resting global ejection fraction and myocardial perfusion, but there was no correlation during exercise, indicating a dissociation between myocardial perfusion and function during exercise conditions in patients with coronary artery disease (CAD). Patients with total coronary occlusions showed more resting defects than patients with partial stenoses. Both groups benefit from PTCA or re-opening of chronic coronary occlusion, respectively. Exercise-induced myocardial ischaemia significantly decreased, and in 36% of the patients with previous myocardial infarction a significant reduction of the size of the resting perfusion defects occurred. In conclusion, our quantification method is suitable for the accurate non-invasive diagnosis of CAD, and for the follow-up of the invasive treatment of coronary artery stenoses and occlusions.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Coração/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Angioplastia Coronária com Balão , Doença das Coronárias/terapia , Teste de Esforço , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/terapia , Valor Preditivo dos Testes
11.
Nuklearmedizin ; 33(3): 106-12, 1994 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-8090624

RESUMO

Sympathetic reinnervation was evaluated in 15 patients 2-69 months after heart transplantation using a double-tracer technique with 123I-MIBG and 201Tl. Since MIBG is accumulated in the same manner as norepinephrine it may serve as a tracer of the integrity and function of the sympathetic nervous system. 201Tl was used for landmarking. Planar anterior imaging was performed 15 min and 4 h after i.v. injection of 220 MBq 123I-MIBG and 37 MBq 201Tl. Image quantitation was based on the ratio of myocardial to mediastinal MIBG-uptake. Cardiac regions of interest were defined according to the 201Tl uptake. There was no evidence of sympathetic reinnervation in 8 patients 2-34 months after transplantation. Increased MIBG-uptake could be observed in the anterior basal region in 6 long-term cardiac transplants (37-69 months). One patient with a 59-month-old transplanted heart did not reinnervate. Increased MIBG-uptake in the anterior basal region indicating partial sympathetic reinnervation could be shown in 40% of the investigated patients with an average organ age of 51 months.


Assuntos
Transplante de Coração/fisiologia , Coração/diagnóstico por imagem , Coração/inervação , Radioisótopos do Iodo , Iodobenzenos , Sistema Nervoso Simpático/fisiologia , Tálio , 3-Iodobenzilguanidina , Adulto , Feminino , Seguimentos , Humanos , Radioisótopos do Iodo/farmacocinética , Iodobenzenos/farmacocinética , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Cintilografia , Tálio/farmacocinética , Fatores de Tempo
12.
Psychiatry Res ; 55(2): 111-8, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10711799

RESUMO

Single photon emission computed tomography (SPECT) with 123I-iodobenzamide (123I-IBZM) was used to study 22 chronic schizophrenic patients. The patients, who were receiving maintenance therapy with typical neuroleptics, had not shown any significant improvement since their admission to the hospital. Basal ganglia/frontal cortex ratios of the uptake of 123I-IBZM did not show significant differences on the basis of neuroleptic dosage in chlorpromazine equivalents. There were, however, significant differences in 123I-IBZM uptake in the basal ganglia among patients characterized by negative, mixed, and positive symptoms of schizophrenia. Although only a small number of patients had shown a positive response to treatment by the time of discharge, D2 receptor blockade was significantly higher in responders than in nonresponders. In addition, there was an inverse correlation between reduced activation as measured by the Brief Psychiatric Rating Scale and the basal ganglia/frontal cortex ratio. These findings suggest a complex pathogenetic link between the blockade of dopamine D2 receptors and psychopathology in chronic schizophrenic patients. SPECT studies with 123I-IBZM appear to have prognostic value in identifying chronic schizophrenic patients who respond poorly to neuroleptic treatment.


Assuntos
Benzamidas , Meios de Contraste , Antagonistas de Dopamina , Pirrolidinas , Receptores de Dopamina D2/fisiologia , Esquizofrenia/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Antipsicóticos/uso terapêutico , Gânglios da Base/diagnóstico por imagem , Gânglios da Base/efeitos dos fármacos , Gânglios da Base/fisiopatologia , Doença Crônica , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/fisiopatologia , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Prognóstico , Escalas de Graduação Psiquiátrica , Receptores de Dopamina D2/efeitos dos fármacos , Esquizofrenia/tratamento farmacológico , Esquizofrenia/fisiopatologia
13.
Nuklearmedizin ; 32(6): 282-7, 1993 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-8295825

RESUMO

Transluminal coronary angioplasty (PTCA) causes transient occlusion of the coronary artery and temporary ischemia of the left ventricle. Left ventricular dysfunction during silent and symptomatic episodes of myocardial ischemia during PTCA was evaluated continuously with a newly developed miniature, non-imaging scintillation probe. Parameters of left ventricular function were compared before and during balloon inflations of 60 s duration: ejection fraction (EF), indices of end-systolic and end-diastolic volumes (ESV, EDV), peak ejection and peak filling rates (PER, PFR). 13 patients (age 54 +/- 7.4 years) were symptomatic, 10 patients (age 61 +/- 8 years) were asymptomatic. Impairment of left ventricular function during ischemia did not show any significant differences between the symptomatic and asymptomatic patients. It is therefore concluded that symptomatic and asymptomatic episodes of myocardial ischemia during PTCA cause similar impairment of systolic and diastolic left ventricular function. The degree of left ventricular dysfunction during PTCA cannot be estimated on the basis of clinical symptoms.


Assuntos
Angioplastia Coronária com Balão , Isquemia Miocárdica/fisiopatologia , Função Ventricular Esquerda/fisiologia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade
14.
Z Kardiol ; 82(9): 531-7, 1993 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-8237093

RESUMO

The purpose of the study was to evaluate the improvement of the left ventricular ejection fraction and myocardial perfusion after recanalization of chronic coronary artery occlusions. The patients were investigated by rest and exercise radionuclide ventriculography (25/31) and rest and exercise myocardial scintigraphy (22/31). The examinations were performed 3 +/- 1 days before and within 7 days and 4 months after recanalization. Exercise-induced chest pain was present in 77% (24/31) of the patients before, in 10% (3/31) after recanalization and in 23% (7/31) during follow-up. Six of the 7 patients with exercise-induced chest pain after 4 months developed restenosis in the former reopened coronary artery. The results of the exercise-ECG present that 71% (22/31) of the patients had ST-segment-depression before, 19% (6/31) after catheter-intervention and 26% (8/31) during follow-up. Six of the 8 patients with exercise-induced ST-depression after 4 months had a restenosis in the former reopened coronary artery. Reopening resulted in an increase of global rest ejection fraction (EF) from 51 +/- 11% to 54 +/- 13% (p < 0.05) and sectorial EF from 56 +/- 17% to 61 +/- 21% (p < 0.01) after recanalization. After 4 months patients with excellent angiographic results still had an increased global and sectorial EF at rest (global: 54 +/- 9%, sectorial: 59 +/- 17%; n.s.). Patients with restenosis (note: no reocclusion) developed a decrease of global and sectorial rest EF (global: 49 +/- 14%, sectorial: 57 +/- 19%; n.s.).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Aterectomia Coronária , Débito Cardíaco/fisiologia , Circulação Coronária/fisiologia , Doença das Coronárias/cirurgia , Função Ventricular Esquerda/fisiologia , Angina Pectoris/diagnóstico por imagem , Angina Pectoris/fisiopatologia , Angina Pectoris/cirurgia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/cirurgia , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/fisiopatologia , Eletrocardiografia , Teste de Esforço , Feminino , Imagem do Acúmulo Cardíaco de Comporta , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/fisiopatologia , Recidiva
15.
Z Kardiol ; 82(9): 538-44, 1993 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-8237094

RESUMO

The purpose of this study was to evaluate if left ventricular ejection fraction (EF) at rest can improve already during the first 4 h after successful transluminal coronary angioplasty (PTCA). Measurements were carried out with the CardioScint LV Function Monitor Version 1.3. Comparison of ejection fraction values evaluated by the CardioScint Monitor revealed a good correlation with usual equilibrium radionuclide ventriculography (n = 28; r = 0.89). Also, intra- and interobserver variability was low (n = 26; r = 0.94 and n = 21; r = 0.92 respectively). Two hundred follow-up-measurements in eight patients over a time period of 4 h revealed a significant decrease of EF from 45 +/- 12% to 39 +/- 18% (p = 0.037) (reference group). This decrease was due to a continuous increase of background activity. The study population consisted of 14 patients with successful PTCA (dilatation from 85 +/- 7 to 34 +/- 9% linear vessel diameter). To evaluate the hemodynamic significance of the coronary lesion, left ventricular ejection fraction was registered during the balloon occlusion of the vessel. After dilatation, 25 EF measurements were carried out in each patient over the following 4 h (350 values). During PTCA, EF decreased from 52 +/- 16 to 37 +/- 9% (p = 0.0027). During the 4-h follow-up EF slightly decreased from 50 +/- 8 to 46 +/- 9% (p = 0.07).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Angioplastia Coronária com Balão , Débito Cardíaco/fisiologia , Doença das Coronárias/terapia , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/fisiopatologia , Eletrocardiografia , Teste de Esforço , Feminino , Imagem do Acúmulo Cardíaco de Comporta , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/terapia
16.
Eur J Nucl Med ; 20(9): 776-82, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8223772

RESUMO

Iodine-123 metaiodobenzylguanidine (MIBG) is a noradrenaline analogue which can be used as a tracer to investigate the cardiac sympathetic nervous system. Regional ischaemia leads to noradrenaline depletion with functional denervation which can be demonstrated by reduced MIBG uptake. In order to evaluate the reversibility of ischaemia-associated damage to the sympathetic nervous system, neuronal scintigraphy with 123I-MIBG and myocardial rest and stress perfusion scintigraphy with technetium-99m sestamibi was performed in 16 patients with coronary artery disease before and 3-4 months after percutaneous transluminal coronary angioplasty (PTCA). Partial re-innervation occurred in five patients, the degree of stenosis of remaining lesions being estimated by repeat angiography to be below 40%. Unchanged MIBG defects could be confirmed in four patients with residual lesions of between 40% and 50%. Increased MIBG defects were shown in three patients with significant restenoses of more than 70%. In all patients the neuronal defects exceeded the ischaemia-induced or scar-associated perfusion defects. Three patients dropped out of this study: one for technical reasons, one due to emergency aortocoronary bypass surgery and one due to diabetic polyneuropathy. This investigation shows that the sympathetic nervous system is highly sensitive to ischaemia. Further studies need to be done to assess the conditions allowing re-innervation after PTCA.


Assuntos
Angioplastia Coronária com Balão , Doença das Coronárias/terapia , Iodobenzenos , Norepinefrina/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único , 3-Iodobenzilguanidina , Adulto , Idoso , Meios de Contraste , Doença das Coronárias/diagnóstico por imagem , Feminino , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade
17.
J Thorac Cardiovasc Surg ; 106(1): 137-48, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8320992

RESUMO

Between 1977 and 1992 a total of 163 consecutive patients underwent emergency coronary artery bypass grafting after acute coronary occlusion (94% after failed angioplasty). Patients were divided into four groups according to the method used for myocardial protection. The crystalloid cardioplegia group included 30 patients operated on from 1977 to 1980; the hypothermic fibrillation group included 60 patients (1980 to 1986); the blood cardioplegia group included 36 patients (1986 to 1989); and the blood cardioplegia with controlled reperfusion group included 37 patients (1989 to 1992). Preoperative data, ischemic time interval, collateral blood flow, intraoperative data, regional wall motion, global ejection fraction, myocardial infarct-specific electrocardiographic changes, enzyme release, rhythm disturbances, mortality, prevalence of intraaortic balloon pumping, and inotropic support were assessed in this retrospective study. Our data indicate that the current spectrum of patients undergoing emergency coronary artery bypass grafting after acute coronary occlusion are at a significantly higher risk compared with those 15 years ago, that is, increase in age (53 +/- 1 versus 59 +/- 2 years; p < 0.05), three-vessel disease (38% versus 3%; p = 0.004), acute occlusion of the left main coronary artery (11% versus 0%; p = 0.02), preoperative cardiogenic shock (35% versus 3%; p = 0.007), prevalence of acute two-vessel occlusion (22% versus 3%; p = 0.05), prevalence of previous infarction (59% versus 23%; p = 0.04), and duration of ischemia (3.0 +/- 0.2 versus 4.1 +/- 0.3 hours; p < 0.05). Despite the increase in patients with severely compromised ventricular function during recent years, the overall hospital mortality decreased to 5% (2/37) when maximal protection of the ischemic and remote myocardium was performed (preoperative intraaortic balloon pump, combined antegrade/retrograde substrate-enriched blood cardioplegia, warm induction, controlled reperfusion, prolonged vented bypass). Single-vessel disease was always associated with a low mortality, whereas mortality could be reduced with controlled blood cardioplegia in patients with multivessel disease (6%) and cardiogenic shock (15%). The immediate return of regional contractility in the previously ischemic area after controlled reperfusion might serve as an explanation for these favorable results. After unmodified blood reperfusion, normokinesis or slight hypokinesis occurs in only 34% to 46% in the early postoperative period (1 to 4 weeks) in comparison with 86% after controlled blood cardioplegia reperfusion (p < 0.05). We conclude that there is a significant increase in risk factors in patients undergoing emergency coronary artery bypass grafting and that improved methods of intraoperative myocardial protection are needed for these compromised patients.


Assuntos
Ponte de Artéria Coronária/métodos , Doença das Coronárias/cirurgia , Parada Cardíaca Induzida/métodos , Doença Aguda , Angioplastia Coronária com Balão/efeitos adversos , Sangue , Soluções Cardioplégicas , Doença das Coronárias/mortalidade , Doença das Coronárias/fisiopatologia , Emergências , Feminino , Mortalidade Hospitalar , Humanos , Hipotermia Induzida , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Reperfusão Miocárdica , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos , Fatores de Risco
18.
Eur J Nucl Med ; 20(2): 146-50, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8440271

RESUMO

Discrepant results have previously been reported concerning long-term left ventricular function in the human transplanted heart as assessed by radionuclide ventriculography. In this study, radionuclide ventriculograms were obtained at rest and during exercise in 19 patients < 6 months, 7-12 months, 13-24 months and > 24 months after transplantation. Ejection fraction decreased significantly from < 6 months to 13-24 months after transplantation (rest: 69.1% +/- 9.7% to 56.7% +/- 8.3%, P < 0.05; exercise: 70.4% +/- 11.3% to 59% +/- 8%, P < 0.05). Heart rate increased significantly during exercise after > 2 years (90.2 +/- 10.5 beats/min to 103.5 +/- 15 beats/min, P < 0.05) but not within 6 months after transplantation (98.5 +/- 12.8 beats/min to 99.07 +/- 15.8 beats/min). Left ventricular end-diastolic volume remained unchanged. Peak filling rate at rest decreased significantly from 4.2 +/- 0.96 edv/s < 6 months after transplantation to 3.3 +/- 0.66 edv/s (P < 0.05) 13-24 months and 3.3 +/- 0.64 edv/s (P < 0.05) > 24 months after cardiac transplantation. Exercise peak filing rate did not change significantly. It is concluded that radionuclide ventriculography demonstrates a decrease in systolic left ventricular function in the long-term course after cardiac transplantation. A significant increase in exercise peak heart rate may be due to autonomic reinnervation. Differences in the literature concerning left ventricular function may be due to different observation intervals following cardiac transplantation.


Assuntos
Imagem do Acúmulo Cardíaco de Comporta , Transplante de Coração/diagnóstico por imagem , Função Ventricular Esquerda/fisiologia , Eritrócitos , Teste de Esforço , Tolerância ao Exercício/fisiologia , Feminino , Seguimentos , Transplante de Coração/fisiologia , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Tecnécio , Fatores de Tempo
19.
Zentralbl Chir ; 118(4): 180-9, 1993.
Artigo em Alemão | MEDLINE | ID: mdl-8493826

RESUMO

This retrospective study was done to assess the results of emergency revascularization in patients with acute myocardial infarction. In addition, the influence of the mode of reperfusion was investigated in terms of morbidity and mortality. Between January 1987 and May 1992, 75 consecutive patients with acute coronary occlusion (in 87% PTCA-failure) received one of two different reperfusion protocols during emergency aortocoronary bypass operation. In 36 patients, the reperfusate was normal blood given at systemic pressure (uncontrolled reperfusion); in 39 patients, the ischemic area was initially reperfused for 20 minutes with a blood cardioplegic solution (substrate-enriched, hyperosmolar, hypocalcemic, alkalotic, diltiazem-enriched) given at 37 degrees C and at a perfusion pressure of 50 mmHg. Thereafter, the heart was kept in the beating empty state for 30 minutes before extra-corporeal circulation was discontinued (controlled reperfusion). Regional contractility (echocardiography, radionuclide ventriculography), electrocardiogram (ECG), release of creatine kinase and MB-isoenzyme of creatine kinase as well as hospital mortality were assessed. Quantification of regional contractility was done with a scoring system from 0 (normokinesis) to 4 (dyskinesis). Data are expressed as mean +/- standard error of the mean (SEM). Both groups were well matched for age, sex, and the distribution of the occluded artery. In the controlled reperfusion group, there was a higher incidence of additional significant stenosis (2.2 +/- 0.1 vs 1.7 +/- 0.1) and cardiogenic shock (36% vs 17%). Furthermore, the interval between coronary occlusion and reperfusion was longer in the controlled reperfusion group (4.1 +/- 0.3 vs 3.3 +/- 0.3 hrs; p > 0.05). Regional contractility returned to normal after controlled reperfusion (score 0.8 +/- 0.2; normokinesis = 0, slight hypokinesis = 1). In contrast, regional contractility remained depressed severely after uncontrolled reperfusion with normal blood (score 1.5 +/- 0.3; p < 0.05). Enzyme release and ECG-changes were similar in both groups postoperatively. While only 2 of 39 patients died in the controlled reperfusion group (5.1%), mortality increased to 11.1% (4/36) if normal blood is used as the primary reperfusate. Our data show, that the surgical revascularization during acute myocardial infarction can be performed with acceptable mortality and morbidity rates. Further improvement of the results can be obtained if controlled regional reperfusion for the previously ischemic area is used.


Assuntos
Ponte de Artéria Coronária , Emergências , Infarto do Miocárdio/cirurgia , Angioplastia Coronária com Balão , Trombose Coronária/mortalidade , Trombose Coronária/fisiopatologia , Trombose Coronária/cirurgia , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Contração Miocárdica/fisiologia , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Reperfusão Miocárdica , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/fisiopatologia , Estudos Retrospectivos , Taxa de Sobrevida
20.
Z Kardiol ; 81(11): 591-5, 1992 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-1471396

RESUMO

To assess the myocardial function before and after reopening of chronic coronary artery occlusions, 20 patients were investigated at rest and during exercise with ECG and equilibrium radionuclide ventriculography. The recanalisation of the chronically occluded vessel was carried out by means of Rotacs-catheter in 17 patients, of a guide wire enforced by recanalisation-catheter in 2 patients and of a thin guide wire alone in 1 patient, always followed by conventional balloon angioplasty. After successful PTCA the average coronary artery stenosis diameter decreased from 100% to 34 +/- 6%. Angina pectoris and/or dyspnea observed during exercise were improved in 83% of the patients. The radionuclide global left ventricular ejection fraction at rest increased from 55 +/- 9% to 59 +/- 10% (p < 0.05), and during exercise from 52 +/- 12% to 61 +/- 12% (p < 0.05). The improvement in global ejection fraction at rest was more pronounced in 5 patients, who suffered from angina pectoris at rest before PTCA (from 56 +/- 4% to 65 +/- 9%, p < 0.05). It is concluded that reopening of chronically occluded coronary arteries in properly selected patients leads to a significant improvement of the global left ventricular function at rest and during exercise.


Assuntos
Angioplastia Coronária com Balão/instrumentação , Doença das Coronárias/terapia , Contração Miocárdica/fisiologia , Isquemia Miocárdica/terapia , Adulto , Idoso , Débito Cardíaco/fisiologia , Circulação Coronária/fisiologia , Doença das Coronárias/fisiopatologia , Eletrocardiografia , Desenho de Equipamento , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Ventriculografia com Radionuclídeos
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