RESUMO
BACKGROUND: Mothers in low-income settings who work in agricultural employment are challenged to meet breastfeeding (BF) recommendations. Recent legislation in Kenya mandates maternity leave and workplace supports, yet the relation of these benefits with BF practices is poorly understood. OBJECTIVES: We evaluated the associations with workplace-provided BF supports and BF practices among formally employed mothers in Kenya. The availability of supports was hypothesized to be associated with a higher prevalence and greater odds of exclusive breastfeeding (EBF). METHODS: We conducted repeated cross-sectional surveys among formally employed mothers at 1-4 d and 6, 14, and 36 wk (to estimate 24 wk) postpartum in Naivasha, Kenya. We used logistic regression adjusted for maternal age, education, physical burden of work, HIV status, and income to evaluate associations between workplace supports and EBF practices. RESULTS: Among formally employed mothers (n = 564), those who used onsite workplace childcare were more likely to practice EBF than those who used community- or home-based childcare at both 6 wk (95.7% compared with 82.4%, P = 0.030) and 14 wk (60.6% compared with 22.2%, P < 0.001; adjusted OR: 5.11; 95% CI: 2.3, 11.7). Likewise, at 14 wk among mothers who currently used daycare centers, a higher proportion of mothers who visited daycare centers at or near workplaces practiced EBF (70.0%) than of those not visiting daycare centers (34.7%, P = 0.005). EBF prevalence was higher among mothers with access to workplace private lactation spaces than among mothers without such spaces (84.6% compared with 55.6%, P = 0.037), and among mothers who lived in workplace housing than those without onsite housing (adjusted OR: 2.06, 95% CI: 1.25, 3.41). CONCLUSIONS: Formally employed mothers in Kenya who have access to and use workplace-provided BF supports were more likely to practice EBF than mothers who lacked these supports. As the Kenya Health Act is implemented, lactation rooms, onsite housing and daycare, and transportation to visit children can all support BF and EBF among employed mothers.
Assuntos
Aleitamento Materno , Mães , Criança , Feminino , Humanos , Gravidez , Lactente , Quênia , Estudos Transversais , Local de TrabalhoRESUMO
Inquiries into properties of brain structure and function have progressed due to developments in magnetic resonance imaging (MRI). To sustain progress in investigating and quantifying neuroanatomical details in vivo, the reliability and validity of brain measurements are paramount. Quality control (QC) is a set of procedures for mitigating errors and ensuring the validity and reliability of brain measurements. Despite its importance, there is little guidance on best QC practices and reporting procedures. The study of hippocampal subfields in vivo is a critical case for QC because of their small size, inter-dependent boundary definitions, and common artifacts in the MRI data used for subfield measurements. We addressed this gap by surveying the broader scientific community studying hippocampal subfields on their views and approaches to QC. We received responses from 37 investigators spanning 10 countries, covering different career stages, and studying both healthy and pathological development and aging. In this sample, 81% of researchers considered QC to be very important or important, and 19% viewed it as fairly important. Despite this, only 46% of researchers reported on their QC processes in prior publications. In many instances, lack of reporting appeared due to ambiguous guidance on relevant details and guidance for reporting, rather than absence of QC. Here, we provide recommendations for correcting errors to maximize reliability and minimize bias. We also summarize threats to segmentation accuracy, review common QC methods, and make recommendations for best practices and reporting in publications. Implementing the recommended QC practices will collectively improve inferences to the larger population, as well as have implications for clinical practice and public health.
RESUMO
BACKGROUND: The aim of this study was to assess the domains of importance in therapeutic intervention for cerebral palsy (CP) using categories of the International Classification of Functioning, Disability, and Health - Children and Youth Version (ICF-CY). METHODS: A total of 17 youth, 19 parents and 39 medical professionals responded to the open-ended query: 'What are the things you find most important to consider when you evaluate the effects of an intervention for yourself/your child/your patient with cerebral palsy?' Surveys were either mailed or conducted on-line. Responses were coded by two reviewers using the ICF-CY and discrepancies were resolved. RESULTS: Responses were distributed across the ICF-CY domains of Body Functions and Structures, Activities and Participation, and Environmental Factors, as well as non-ICF-CY concepts including quality of life. The most common responses overall were pain, motor function, mobility, community life and public services. Youth identified strength, gait pattern, hand/arm use and use of assistive technologies as priorities whereas parents were concerned with motor function, communication, mobility and provision of public services. Medical professionals listed pain, function, mobility, community life and participation most often. CONCLUSIONS: All surveyed groups indicate a desire to see changes in body functions and structures (pain, mental function, strength, movement), activities and participation (communication, hand/arm use, walking, school, recreation/community life) and quality of life following therapeutic interventions for CP. These results demonstrate the multiple, varied concerns regarding CP across the spectrum of functioning and health.
Assuntos
Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Paralisia Cerebral/reabilitação , Pais/psicologia , Atividades Cotidianas , Adolescente , Paralisia Cerebral/fisiopatologia , Criança , Avaliação da Deficiência , Prioridades em Saúde , Humanos , Ohio , Qualidade de Vida , Resultado do TratamentoRESUMO
BACKGROUND: A family was identified with autosomal dominant inheritance of anemia, polyuria, hyperuricemia, and chronic kidney disease. Mutational analysis revealed a novel heterozygous mutation c.58T > C resulting in the amino acid substitution of cysteine for arginine in the preprorenin signal sequence (p.cys20Arg) occurring in all affected members. METHODS: Effects of the identified mutation were characterized using in vitro and in vivo studies. Affected individuals were clinically characterized before and after administration of fludrocortisone. RESULTS: The mutation affects endoplasmic reticulum co-translational translocation and posttranslational processing, resulting in massive accumulation of non-glycosylated preprorenin in the cytoplasm. This affects expression of intra-renal RAS components and leads to ultrastructural damage of the kidney. Affected individuals suffered from anemia, hyperuricemia, decreased urinary concentrating ability, and progressive chronic kidney disease. Treatment with fludrocortisone in an affected 10-year-old child resulted in an increase in blood pressure and estimated glomerular filtration rate. CONCLUSIONS: A novel REN gene mutation resulted in an alteration in the amino acid sequence of the renin signal sequence and caused childhood anemia, polyuria, and kidney disease. Treatment with fludrocortisone improved renal function in an affected child. Nephrologists should consider REN mutational analysis in families with autosomal dominant inheritance of chronic kidney disease, especially if they suffer from anemia, hyperuricemia, and polyuria in childhood.
Assuntos
Fludrocortisona/uso terapêutico , Genes Dominantes , Nefropatias/tratamento farmacológico , Nefropatias/genética , Mutação , Sinais Direcionadores de Proteínas/genética , Renina/genética , Adulto , Sequência de Aminoácidos , Anemia/genética , Anemia/metabolismo , Sequência de Bases , Biópsia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/genética , Linhagem Celular , Criança , Doença Crônica , Quimosina , Citoplasma/metabolismo , Análise Mutacional de DNA , Retículo Endoplasmático/metabolismo , Precursores Enzimáticos , Feminino , Predisposição Genética para Doença , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/genética , Glicosilação , Heterozigoto , Humanos , Hiperuricemia/genética , Hiperuricemia/metabolismo , Hipoaldosteronismo/genética , Hipoaldosteronismo/metabolismo , Capacidade de Concentração Renal/genética , Nefropatias/metabolismo , Nefropatias/patologia , Nefropatias/fisiopatologia , Masculino , Dados de Sequência Molecular , Linhagem , Fenótipo , Poliúria/genética , Poliúria/metabolismo , Processamento de Proteína Pós-Traducional , Transporte Proteico , Renina/metabolismo , Transfecção , Resultado do TratamentoRESUMO
OBJECTIVE: To assess the frequency with which paramedic skills were used in out of hospital cardiac arrest and the effect of tracheal intubation on outcome. DESIGN: Retrospective analysis of ambulance service reports and hospital records. SETTING: Scottish Ambulance Service and hospitals admitting acute patients throughout Scotland. RESULTS: A total of 8651 out of hospital resuscitation attempts were recorded and tracheal intubation was attempted in 3427 (39.6%) arrests. One hundred and thirty six patients (3.7%) were intubated and 476 (9.1%) of the patients who were not intubated survived to hospital discharge (p < 0.001). Among the patients who were defibrillated the proportion intubated was highest in the patients who received the greatest number of shocks (p < 0.01). Among subjects receiving similar numbers of shocks survival rates were lower for intubated patients (p < 0.01). Patients with unwitnessed arrests were most frequently intubated and survival rates were lowest in this group. CONCLUSIONS: Patients who are intubated seem to have lower survival rates. This may however reflect the difficulty of the resuscitation attempt rather than the effects of intubation. The use of basic life support skills rapidly after cardiac arrest is associated with the best survival rates.
Assuntos
Serviços Médicos de Emergência/estatística & dados numéricos , Parada Cardíaca/terapia , Intubação Intratraqueal/estatística & dados numéricos , Distribuição de Qui-Quadrado , Cardioversão Elétrica , Serviços Médicos de Emergência/métodos , Parada Cardíaca/mortalidade , Humanos , Estudos Retrospectivos , Escócia , Estatísticas não Paramétricas , Taxa de Sobrevida , Fatores de Tempo , Resultado do TratamentoRESUMO
A 39 year old woman sustained life threatening arrhythmias associated with coronary artery spasm. On both occasions she was attending hospital outpatient clinics and was successfully resuscitated. Electrocardiography performed during further episodes of pain suggested that spasm could occur in either the right or left coronary artery.
Assuntos
Arritmias Cardíacas/etiologia , Vasoespasmo Coronário/complicações , Antagonistas Adrenérgicos beta , Adulto , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/prevenção & controle , Atenolol/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Contraindicações , Vasoespasmo Coronário/fisiopatologia , Vasoespasmo Coronário/prevenção & controle , Eletrocardiografia Ambulatorial , Feminino , Parada Cardíaca/etiologia , Parada Cardíaca/prevenção & controle , HumanosRESUMO
OBJECTIVE: To establish the incidence of hibernating myocardium after myocardial infarction treated with thrombolysis and to observe differences in the clinical outcome between patients with and without hibernating tissue. METHODS: 41 patients underwent gated positron emission tomography with 18-fluorodeoxyglucose and 13N-ammonia at a median of eight days after first myocardial infarction. RESULTS: All 41 subjects had a matched perfusion-metabolism deficit in the region of myocardium indicated as the site of infarction by an electrocardiograph; 32 patients (78%) had scans which also showed at least one area of reduced blood flow and contraction with a concomitant increase in glucose uptake, representing hibernating myocardium. Patients were followed up at a median of six months: all 41 were alive and none had sustained a further infarct or cardiac arrhythmia; 17 subjects with hibernating tissue (53.1%) and two without (25%) reported chest pain after myocardial infarction. CONCLUSIONS: Hibernating myocardium is relatively common shortly after myocardial infarction treated with thrombolysis. It does not influence mortality or the incidence of postinfarction chest pain.
Assuntos
Infarto do Miocárdio/tratamento farmacológico , Miocárdio Atordoado/etiologia , Estreptoquinase/uso terapêutico , Terapia Trombolítica , Idoso , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio Atordoado/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Resultado do TratamentoRESUMO
The risk of administering thrombolysis to patients with suspected myocardial infarction who subsequently do not sustain an infarct, but develop complications associated with thrombolysis is of concern to all physicians. The objective of this study was to ascertain the effect of altering the criteria for the administration of thrombolysis on the number of patients who received thrombolysis in the absence of infarction. During 1990 and 1992 details of all admissions with chest pain were recorded. During 1991 the policy for the administration of thrombolysis was altered so that only patients with ST elevation were eligible. A total of 1473 patients were admitted with chest pain in 1990 and 1967 in 1992. Of the patients admitted in 1990, 663 (45%) had confirmed infarction of whom 378 (57.0%) received thrombolysis. In 1992, 855 (43%) were admitted with infarction and of these 450 (52.6%) had thrombolytic therapy. 118 patients had no evidence of myocardial infarction, but received thrombolysis. 91 (77.1%) were admitted in 1990 and 27 (22.9%) in 1992 (P < 0.01). Of these only 24 (20%) subjects had ST elevation or bundle branch block on the admission electrocardiograph and 41 (35%) had normal tracings. Four (3%) subjects had serious complications of whom one (0.8%) died. The implementation of ECG criteria resulted in a significant reduction in the number of patients without infarction who received thrombolysis, but did not significantly alter the rate of thrombolysis in those with definite myocardial infarction.
Assuntos
Terapia Trombolítica/efeitos adversos , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/tratamento farmacológico , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/tratamento farmacológico , Dor no Peito/diagnóstico , Dor no Peito/tratamento farmacológico , Angiografia Coronária , Doença das Coronárias/diagnóstico , Doença das Coronárias/tratamento farmacológico , Tomada de Decisões , Eletrocardiografia , Humanos , Auditoria Médica , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/tratamento farmacológico , Admissão do Paciente , Alta do Paciente , Formulação de Políticas , Estudos Retrospectivos , Fatores de RiscoRESUMO
OBJECTIVE: To identify the effect on door to needle (DTN) time of moving the site of thrombolysis delivery from the coronary care unit (CCU) to the emergency department (ED). To ascertain if moving the site of thrombolysis enables appropriate use of thrombolysis. DESIGN: Prospective cohort study. SETTING: CCU and ED of a 450 bed Scottish district general hospital without on-site primary angioplasty. PARTICIPANTS: Primary site for thrombolysis of patients presenting to the hospital with ST elevation MI (STEMI) moved from CCU to ED on 1 April 2000. Study patients who had a confirmed STEMI and/or received thrombolytic therapy before this date were defined as the pre-change group; those who were diagnosed as STEMI and/or received thrombolytic therapy after this date were defined as the post-change group. STATISTICAL ANALYSIS: Mann-Whitney test was used to compare medians and chi(2) test for categorical data. RESULTS: 1349 patients were discharged from CCU with a diagnosis of STEMI or received thrombolysis in the ED or CCU between April 1998 and April 2002. There were 632 patients in the pre-change group and 654 patients in the post-change group. Sixty three patients were excluded. Median DTN time for the pre-change group (321 thrombolysed patients) was 64 minutes and median DTN time for the post-change group (324 thrombolysed patients) was 35 minutes, a median difference of 25 minutes (95% CI for difference 20 to 29 minutes, p<0.0001, Mann-Whitney U test). A total of 37 patients were thrombolysed but did not have a final diagnosis of STEMI. CONCLUSION: A significant reduction in DTN times accompanied this change in practice in this hospital.
Assuntos
Serviço Hospitalar de Emergência/organização & administração , Infarto do Miocárdio/tratamento farmacológico , Terapia Trombolítica , Idoso , Unidades de Cuidados Coronarianos/organização & administração , Tratamento de Emergência , Feminino , Humanos , Masculino , Estudos Prospectivos , Encaminhamento e Consulta , Fatores de TempoRESUMO
Segregation of genes specifying nutritional requirements and inhibitor resistance was analyzed in recombinants from crosses of Nocardia erythropolis with N. canicruria. With all employed characters as both selecting and nonselecting markers, a single linear linkage group was depicted with genes in the following order; leu-6 gly-4 purB2 tetA9 his-1 eryA7 strB2 ser-1 arg-1. The relative frequency of crossovers between gene pairs was found to decrease as the map is read from leu-6 to the right. The phenotype for arg-1 was found infrequently in recombinants. This fact, coupled with the observed decrease in crossover frequency dependent upon map position, suggested two alternative explanations to account for the observed results. (i) Zygote formation among these nocardiae is a consequence of partial, oriented chromosome transfer from N. erythropolis to N. canicruria and is similar to the mechanism of polar transfer reported in matings of Hfr by F(-)Escherichia coli. (ii) Being of diverse origin, the chromosomes of N. erythropolis and N. canicruria are not completely homologous, and decrease in crossover frequency dependent upon map position results from such chromosomal heterology. In this hypothesis, the infrequent occurrence of arg-1 among recombinants is considered to be an artifact resulting from the action of a previously unrecognized suppressor gene for arg-1 present in N. canicruria.
Assuntos
Mapeamento Cromossômico , Cromossomos Bacterianos , Conjugação Genética , Cruzamentos Genéticos , Resistência Microbiana a Medicamentos , Genética Microbiana , Mutação , Nocardia , Recombinação Genética , Seleção GenéticaRESUMO
An electronic device using transistor-transistor-logic integrated circuits as primary building blocks was designed and constructed to accumulate counts for eight classtypes. Selection of the classtypes is provided for by three encoders, X, Y, and Z. Using these encoders allows selection of memory counters for accumulations of 0 to 99 counts per classtype. Making X, Y, and Z the input equivalents of three genes permitted direct tallying and accumulation of totals of individual phenotypes for recombinant progeny containing three scorable genes. The use of the device as a simple one-of-four colony counter is described. Use of the instrument for obtaining counts of multiply characterized colonies was possible. In all tested instances, tedium and the labor of obtaining differential counts was reduced by more than fourfold with a great increase in accuracy of count accumulations. Complete information is provided for the fabrication of the instrument for use in individual laboratories.
Assuntos
Bactérias/classificação , Contagem de Células/instrumentação , Classificação/métodos , Eletrônica/instrumentação , Genes , Fenótipo , Recombinação GenéticaRESUMO
The use of anticoagulation in the elderly is increasing. Although several studies show that elderly patients are at greater risk of anticoagulant-associated haemorrhage, most studies suggest that there is no increased risk if the international normalized ratio is well controlled.
Assuntos
Hemorragia/induzido quimicamente , Varfarina/efeitos adversos , Fatores Etários , Idoso , Monitoramento de Medicamentos/métodos , Hemorragia/epidemiologia , Hemorragia/prevenção & controle , Humanos , Metanálise como Assunto , Pessoa de Meia-Idade , Varfarina/farmacocinéticaRESUMO
Lysogens of Nocardia erythropolis were mated with nonlysogenic strains to study the inheritance of the phi EC prophage. Crosses between lysogenic strains of the Mat-Ce mating type and nonlysogenic Mat-cE strains produced Mat-cE lysogens at a recovery rate of 17%, whereas recombination frequencies between chromosomal traits were about 2.3 x 10(-5). Crosses of lysogenic Mat-cE mating types with nonlysogenic Mat-Ce produced Mat-Ce lysogens at a recovery rate of 19%, whereas recombinants for chromosomal traits were recovered at only 1.8 x 10(-5). Crosses of homologous mating types, lysogenic Mat-Ce with nonlysogenic Mat-Ce or lysogenic Mat-cE with nonlysogenic Mat-cE, failed to transfer the prophage. It was concluded that the phi EC prophage exists as a plasmid and can be transferred at high frequencies with patterns of transfer controlled like typical nocardial fertility. Evidence that the prophage may also exist as an integrated element was observed from recombination analyses.
Assuntos
Bacteriófagos/crescimento & desenvolvimento , Conjugação Genética , Lisogenia , Nocardia , Mapeamento Cromossômico , Ligação Genética , Fenótipo , Plasmídeos , Recombinação GenéticaRESUMO
Minimal medium supplemented with sub-optimal levels of parental auxotrophic requirements increases recombinant recovery from matings of Nocardia erythropolis more than 500-fold when compared with nutrient agar matings.
Assuntos
Conjugação Genética , Meios de Cultura , Nocardia , Recombinação Genética , Bromouracila/farmacologia , Sobrevivência Celular , Cruzamentos Genéticos , Mutação , Nocardia/citologia , Nocardia/efeitos dos fármacos , Nocardia/efeitos da radiação , Efeitos da Radiação , Raios UltravioletaRESUMO
The segregation of unselected genes expressing resistance or susceptibility to acriflavine, erythromycin, streptomycin, and tetracycline was analyzed in selected prototrophic recombinants resulting from matings of Nocardia erythropolis and N. canicruria. The organisms were shown to be functionally haploid and appeared to contain not more than one genome. It was postulated that all observed genes were present in a linear linkage group. The ordering of the genes in N. erythropolis was: tetB10 eryB9 his-3 purA1 acr-2 strA1 (respectively, resistance to tetracycline and erythromycin, deficiency for histidine and for purine, and resistance to acriflavine and streptomycin). The ordering of the genes in N. canicruria was: purB2 tetA9 eryA7 acr-11 strB2 (respectively, deficiency for purine, and resistance to tetracycline, erythromycin, acriflavine, and streptomycin). Excluding the genes for acriflavine resistance, acr-2 and acr-11, resistance loci in N. erythropolis were not allelic to and showed lateral displacement from genes controlling phenotypically similar resistance in N. canicruria. Evidence for some lack of homology between N. erythropolis and N. canicruria genomes was found. Recombination phenomena between the nocardial species was postulated to occur as a result of formation of a heterogenomic zygote in which new combinations were produced. Production of selectable, haploid recombinants was ascribed to subsequent haploidization of the zygote.
Assuntos
Genética , Nocardia , Mapeamento Cromossômico , Biologia Molecular , MutaçãoRESUMO
A program is presented which permits use of a pocket-size programmable calculator, the HP-65, to tally phenotypes resulting from a three-point cross. For practical purposes the total number recorded for any of the eight possibel phenotypic combinations is unlimited. Although programmed operation of the calculator for tallying purposes is slower than a single purpose instrument designed for tallying, this deficiency is componensated by the computational capability of this instrument.
Assuntos
Computadores , Genética/instrumentação , Fenótipo , Cruzamentos GenéticosRESUMO
OBJECTIVE: To determine whether women with myocardial infarction are treated differently from men of the same age and to assess the effect of changes in the coronary care unit admission policy. DESIGN: Clinical audit. SETTING: The coronary care unit and general medical wards of a teaching hospital. In 1990 the age limit for admission to coronary care was 65 years. This age limit was removed in 1991. PATIENTS: 539 female and 977 male patients admitted with myocardial infarction between 1990 and 1992. MAIN OUTCOMES: Admission to the coronary care unit, administration of thrombolysis, and in-hospital mortality. RESULTS: 409 men and 254 women were admitted with myocardial infarction in 1990 and 568 men and 285 women in 1992. Removal of the age limit for admission to the coronary care unit resulted in an increase in the numbers of both sexes admitted with myocardial infarction. In both years, however, proportionately more men with infarction were admitted to coronary care: 226 men (55%) and 96 women (38%) (P < 0.01) (95% CI 7 to 28) in 1990 and 459 men (81%) and 200 women (70%) (P < 0.01) (%CI 2 to 19) in 1992. Some 246 men (60%) and 133 women (52%) with infarction (P < 0.01) received thrombolytic treatment in 1990 compared with 319 men (56%) and 130 women (46%) (P < 0.01) in 1992. The mean age of women sustaining a myocardial infarction was significantly greater in both years studied. In 1992 a total of 78 men (7%) and 34 women (4%) (P < 0.05) admitted with chest pain underwent cardiac catheterisation before discharge from hospital. CONCLUSIONS: Differences in admission rates to the coronary care unit and the rate of thrombolysis between the sexes can be explained by the older age of women sustaining infarction. The application of age limits for admission to coronary care or administration of thrombolysis places elderly patients at a disadvantage. As women sustain myocardial infarctions at an older age they are placed at a greater disadvantage.
Assuntos
Infarto do Miocárdio/terapia , Seleção de Pacientes , Preconceito , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Escócia/epidemiologia , Fatores Sexuais , Terapia TrombolíticaRESUMO
OBJECTIVE: To establish the persistence of hibernating myocardium initially detected after myocardial infarction treated with thrombolysis. METHODS AND RESULTS: Fourteen patients underwent gated positron emission tomography with 18-fluoro-deoxyglucose and N13-ammonia at a median of 8 days after first myocardial infarction. Repeat scans were performed at a median of 13 weeks post-infarction. A total of 148 (30.9%) myocardial segments showed reduced N13-ammonia uptake at the time of the first scan compared with 154.5 (32.2%) segments at the time of repeat imaging. The median change in the number of segments with reduced perfusion was -1.0. Initially 13 subjects had hibernating myocardium, seven patients had large areas and six had smaller regions. Six (46.2%) subjects had repeat scans showing unchanged areas of hibernating tissue and seven had second scans demonstrating changes in the size of the region of hibernating myocardium. One patient had no hibernating myocardium on either scan. CONCLUSIONS: Positron emission tomography performed several months after myocardial infarction demonstrates significant changes in myocardial perfusion. However, a reduction in the number of segments with reduced perfusion does not always result in an improvement in myocardial metabolism and contraction. Whilst most regions of hibernating myocardium were still present several months after infarction, in only approximately half was the size of the mismatched region unchanged. Therefore it is not possible to predict the fate of hibernating myocardium which is present after infarction.
Assuntos
Infarto do Miocárdio/complicações , Miocárdio Atordoado/etiologia , Miocárdio Atordoado/fisiopatologia , Idoso , Amônia , Circulação Coronária , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/fisiopatologia , Miocárdio Atordoado/diagnóstico por imagem , Radioisótopos de Nitrogênio , Compostos Radiofarmacêuticos , Tomografia Computadorizada de EmissãoRESUMO
OBJECTIVE: To determine whether the interval between the onset of symptoms of acute myocardial infarction and the patient's call for medical assistance (patient delay) is related to left ventricular function at the time of presentation. DESIGN: Prospective observational study. SETTING: Coronary care unit of Aberdeen Royal Infirmary. PATIENTS: 93 consecutive patients with acute myocardial infarction. MAIN OUTCOME MEASURES: Left ventricular stroke distance, expressed as a percentage of the age predicted normal value, measured first on admission, and then daily for 10 days or until discharge. Patients were questioned at admission to determine the time of onset of symptoms and the time of their call for medical assistance. RESULTS: Median (range) patient delay was 30 (1-360) min. Mean (SD) stroke distance on admission was 70(18)%, rising to 77(19)% on the second recording, and to 84(18)% on the day of discharge. Linear regression of log(e)(patient delay) against first, second, and last measurements of stroke distance gave correlation coefficients of 0.28 (P < 0.01), 0.18 (not significant), and 0.11 (not significant), respectively. CONCLUSIONS: Patient delay within the first 4 h after the onset of symptoms of acute myocardial infarction is positively related to left ventricular function on admission. A possible explanation is that deteriorating left ventricular function influences the patient's decision to call for help. This tendency for patients with more severe infarction to call for help sooner is an added reason for giving thrombolytic treatment at the first opportunity: those who call early have most to gain from prompt management.