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1.
Klin Monbl Augenheilkd ; 233(5): 633-8, 2016 May.
Artigo em Alemão | MEDLINE | ID: mdl-27187885

RESUMO

PURPOSE: Evaluation of the clinical data 3 months after implantation of a new diffractive multifocal intraocular lens (MIOL) with a reduced near add power of + 2.75 D. METHODS: In a prospective study, patients who underwent cataract surgery or refractive lens exchange with implantation of an MIOL (Tecnis ZKB00, Abbott Medical Optics, Santa Ana, California, USA) were included. Three months postoperative corrected and uncorrected visual acuities at different distances were measured and evaluated. Those patients that underwent bilateral MIOL implantation additionally filled out a questionnaire 3 months postoperatively. RESULTS: Between October 2013 and August 2014, 115 eyes of 62 patients were implanted with the ZKB00 IOL. Mean postoperative refractions were - 0.27 ± 0.44 D for the spherical equivalent, respectively. Mean binocular CDVA was - 0.01 ± 0.3 logMAR with a mean binocular UDVA of 0.06 ± 0.08 logMAR. For near distance in 40 cm, an UNVA of 0.07 ± 0.10 logMAR three months postoperatively was measured. CONCLUSION: The ZKB00 IOL belongs to a group of novel MIOL with an increased intermediate visual performance. Our study shows good visual acuity at all distances, as well as a high rate of satisfaction and subjectively good image quality.


Assuntos
Extração de Catarata/efeitos adversos , Extração de Catarata/reabilitação , Implante de Lente Intraocular , Lentes Intraoculares/classificação , Erros de Refração/etiologia , Erros de Refração/terapia , Idoso , Idoso de 80 Anos ou mais , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Desenho de Prótese , Erros de Refração/diagnóstico , Resultado do Tratamento , Acuidade Visual
2.
Minerva Gastroenterol Dietol ; 53(4): 375-82, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18043554

RESUMO

The first studies about fertility and nutrition date back to the 70ies and already showed a strict relation among female fertility, weight and body composition. However, the mechanisms of this connection started to be explained only after leptin's discovery. According to some authors' opinion, leptin could interact with reproductive axis at multiple sites with stimulatory effects at the hypothalamus and pituitary and stimulatory or inhibitory actions at the gonads. Leptin could play a role in other physiologic processes such as menstruation and pregnancy, and could initiate the complex process of puberty. It has been showed that conditions in which nutritional status is suboptimal, such as eating disorders, exercise induced amenhorrea, functional hypothalamic amenhorrea and polycystic ovarian syndrome, are associated with abnormal leptin levels. These conditions, are characterized by severe changes in body composition and dietary habits. Since leptin is regulated by body composition and dietary factors, (such as energy intake and macronutrient composition), a strict connection between nutritional intake and fertility regulated by leptin is confirmed. This review focuses on the current knowledge about nutritional factors that influence leptin levels. Since clinical and subclinical nutritional imbalance can determine the development and the maintenance of neuroendocrine and metabolic aberrations, studies on fertility need a deeper attention about dietary habits and nutritional status.


Assuntos
Fertilidade/fisiologia , Leptina/fisiologia , Fenômenos Fisiológicos da Nutrição , Adolescente , Adulto , Composição Corporal , Ingestão de Energia , Comportamento Alimentar , Transtornos da Alimentação e da Ingestão de Alimentos/sangue , Feminino , Humanos , Leptina/sangue , Menstruação/fisiologia , Estado Nutricional , Gravidez , Puberdade/fisiologia
3.
J Am Coll Cardiol ; 27(4): 847-52, 1996 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8613613

RESUMO

OBJECTIVES: The aim of this study was to investigate the relation between "ischemic" sudden death (arrhythmic death preceded by ST segment shift) and autonomic nervous system activity. Background. Mechanisms precipitating sudden death are poorly known despite the importance of detecting functional factors that may contribute to such a fatal event. METHODS: We analyzed the tapes of eight patients (seven men and one woman with a mean age of 66 +/- 8 years) who had ischemic sudden death during ambulatory electrocardiographic (Holter) monitoring. Four patients had unstable and four had stable angina; none was taking antiarrhythmic drugs. Twenty patients with angina and transient myocardial ischemia during Holter monitoring served as control subjects. Arrhythmias, ST segment changes and heart rate variability were analyzed by a computerized interactive Holter system. RESULTS: Five patients had ventricular tachyarrhythmias (ventricular fibrillation in three, ventricular tachycardia in two), and three had bradyarrhythmias (atrioventricular block in two, sinus arrest in one) as the terminal event; all eight patients showed ST segment shift (maximal change 0.46 +/- 0.16 mV; with ST elevation in two) that occurred 41 +/- 34 min (mean +/- SD) before sudden death. The standard deviation of normal RR intervals (SDNN) was 89 +/- 33 ms during the 10 +/- 6 h of Holter monitoring; 5 min before the onset of the fatal ST shift, SDNN measurements were significantly lower than during the initial 5-min period (48 +/- 10 vs. 29 +/- 9 ms; p=0.002). In control patients, the SDNN was 102 +/- 39 ms during Holter monitoring, whereas it measured 56 +/- 30 ms 5 min before the most significant episode of ST shift (p<0.01 vs. 29 +/- 9 ms [corrected] in the group with sudden death). CONCLUSIONS: Autonomic dysfunction, as detected by a marked decrease in heart rate variability, is present in the period (5 min) immediately preceding the onset of the ST shift precipitating ischemic sudden death. These data suggest that sympathovagal imbalance may trigger fatal arrhythmias during acute myocardial ischemia, thus resulting in sudden death.


Assuntos
Doenças do Sistema Nervoso Autônomo/complicações , Morte Súbita Cardíaca/etiologia , Eletrocardiografia Ambulatorial , Isquemia Miocárdica/etiologia , Sistema Nervoso Simpático/fisiopatologia , Nervo Vago/fisiopatologia , Idoso , Arritmias Cardíacas/etiologia , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia
4.
Neuropharmacology ; 24(2): 99-105, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2986034

RESUMO

The effects of the acute administration of 2-phenylpyrazolo[4,3-c]quinolin-3(5H)-one on diazepam-induced behaviour and electrophysiological activity were studied in rat. The compound, in doses of 5-10 mg/kg (i.p.), which per se did not induce alterations in spontaneous locomotor activity, antagonised the sedative effect induced by 5-10 mg/kg (i.p.) of diazepam. The injection of diazepam in rats, induced a profound reduction in the first negative wave of the recording of the visual evoked potential used as a sensitive electrophysiological test, in vivo. 2-Phenylpyrazolo[4,3-c]quinolin-3(5H)-one (10 mg/kg, i.p.) caused a recovery of the amplitude of the first negative wave within a few minutes. This result was confirmed by the finding that 2-phenylpyrazolo[4,3-c]quinolin-3(5H)-one, injected acutely in rats, pretreated with diazepam exhibited the capacity to antagonise the binding of [3H]diazepam determined in vitro on synaptic membrane preparations from cortex. The comparison of the pattern of the visual-evoked potential, recorded after the injection of 2-phenylpyrazolo[4,3-c]quinolin-3(5H)-one (50 mg/kg) with the patterns recorded after the injection of ethyl-8-fluoro-5,6-dihydro-5-methyl-6-oxo-4H-imidazolo(1,5a) (1,4)benzodiazepine-3-carboxylate (50 mg/kg) and ethyl-beta-carboline-3-carboxylate and 1-methyl-beta-carboline demonstrated that 2-phenylpyrazolo[4,3-c]quinolin-3(5H)-one is devoid of intrinsic activity.


Assuntos
Encéfalo/efeitos dos fármacos , Diazepam/antagonistas & inibidores , Potenciais Evocados Visuais/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Pirazóis/farmacologia , Animais , Ligação Competitiva , Córtex Cerebral/metabolismo , Diazepam/metabolismo , Técnicas In Vitro , Masculino , Pirazóis/metabolismo , Ratos , Ratos Endogâmicos , Receptores de GABA-A/metabolismo
5.
Transplantation ; 58(4): 414-8, 1994 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-8073509

RESUMO

Changes in hemodynamic and metabolic parameters (systemic oxygen delivery, [DO2], oxygen consumption [VO2], arterial lactate content) in brain-dead and control pigs in the absence of any inotropic or fluid support were studied. Brain death was induced by the inflation of a Foley catheter balloon placed into the subdural space of the animals. Serial atrial natriuretic peptide (ANP) determinations were performed to evaluate concomitant changes occurring in the endocrine function of the heart. Experiments were completed by a volume expansion protocol to provide a dynamic evaluation of these parameters. A significant increase in heart rate (from 113 +/- 5 to 176 +/- 11 beats/min), pulmonary capillary wedge pressure (from 7 +/- 1 to 12 +/- 3 mmHg), dP/dt (from 2040 +/- 340 to 4200 +/- 660 mmHg/sec-1), cardiac output (from 2.4 +/- 0.2 to 3.3 +/- 0.4 L/min), mean arterial pressure (from 66 +/- 8 to 93 +/- 14 mmHg), and systemic oxygen delivery (from 360 +/- 30 to 530 +/- 90 ml/min-1), was observed following brain death induction. These parameters returned below basal values within 60 min. On the contrary, serum lactate and VO2 remained unchanged. Following volume expansion, brain-dead pigs exhibited impaired hemodynamic response, with a significant decrease in dP/dt, MAP, and DO2. These changes were accompanied by a significant decrease in VO2 and a significant increase in lactate plasma levels. At the same time, a similar increase in ANP release was observed in both groups in response to volume expansion, suggesting that despite impaired myocardial contractility, endocrine function of the heart was preserved following brain death. We conclude that brain death leads to early impaired left ventricular contractility, which could be responsible for the changes observed in aerobic to anaerobic metabolism in response to rapid volume infusion. These results suggest that the use of fluid infusion to reduce the need in inotropic support in conventional therapeutic modalities should be used with care in the management of a brain-dead potential organ donor.


Assuntos
Morte Encefálica/fisiopatologia , Encéfalo/metabolismo , Hemodinâmica/fisiologia , Animais , Fator Natriurético Atrial/sangue , Modelos Animais de Doenças , Lactatos/sangue , Ácido Láctico , Contração Miocárdica/fisiologia , Consumo de Oxigênio , Suínos , Vasopressinas/sangue , Função Ventricular Esquerda/fisiologia
6.
Transplantation ; 57(3): 371-7, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8108872

RESUMO

Brain death is a pathophysiological condition associated with major hemodynamic changes, temporary myocardial ischemia, and histological damage of the heart. These modifications could be related to a major local release of norepinephrine from myocardial sympathetic nerve endings leading to norepinephrine cardiotoxicity. This study was designed to evaluate the utility of cardiac microdialysis to measure interstitial myocardial norepinephrine release resulting from brain death. The dialysis probe consisted in a 10 x 0.20-mm dialysis fiber with a 18,000 mol wt cutoff. Dialysis probes were implanted into the right and left ventricular walls of the beating heart in anesthetized pigs and perfused with Ringer solution at 2 microliters/min. Dialysate norepinephrine concentration was measured using HPLC with electrochemical detection. The relative recovery rate of norepinephrine in vivo was 34 +/- 4%. Interstitial fluid concentrations were obtained using the following formula: [C]interstitium = [C]dialysate/Recovery in vivo. After brain death, a transient increase in interstitial norepinephrine concentration was observed (from 0.74 +/- 0.20 to 4.50 +/- 0.60 ng/ml and 0.76 +/- 0.20 to 6.2 +/- 0.9 ng/ml in left and right ventricle, respectively, P < 0.01) which far exceeded plasma level increase (from 0.50 +/- 0.10 ng/ml to 0.91 +/- 0.20 ng/ml, P < 0.05). This increase in myocardial norepinephrine was, moreover, biphasic, with a second peak occurring 40 min after brain death. The present study confirms the onset of a dramatic increase in cardiac norepinephrine release from myocardial nerve endings following brain death, and demonstrate the utility of the new cardiac microdialysis technique to assess changes in interstitial fluid content.


Assuntos
Morte Encefálica/metabolismo , Miocárdio/metabolismo , Norepinefrina/metabolismo , Animais , Morte Encefálica/fisiopatologia , Espaço Extracelular/química , Hemodinâmica , Microdiálise , Terminações Nervosas/metabolismo , Norepinefrina/análise , Suínos , Sistema Nervoso Simpático/metabolismo , Fatores de Tempo
7.
Am J Cardiol ; 59(6): 596-600, 1987 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-3825900

RESUMO

To determine the frequency and severity of cardiac arrhythmias in intracranial subarachnoid hemorrhage, 120 nonselected patients were prospectively studied by 24-hour Holter monitoring. Arrhythmias were found in 96 of 107 patients (90%) with adequate Holter recording: ventricular premature complexes in 49, nonsustained ventricular tachycardia in 5, supraventricular premature complexes in 29, paroxysmal supraventricular tachycardia or atrial fibrillation in 9, sinoatrial block and arrest in 29, second-degree atrioventricular block in 1, atrioventricular dissociation in 4 and idioventricular rhythm in 2. Life-threatening ventricular arrhythmias (torsades de pointes-type ventricular tachycardia) occurred in 4 patients, degenerating into either ventricular flutter or fibrillation in 2. ST-segment changes suggestive of acute transitory myocardial ischemia were found in 8 patients (1.5 mm or more of ST depression in 7 patients and 1.5 mm or more of ST elevation in 1 patient). The frequency and severity of arrhythmias were significantly higher in patients studied within 48 hours of subarachnoid hemorrhage; serious ventricular arrhythmias were associated with QTc prolongation more than 550 ms and with hypokalemia less than 3.5 mEq/liter. No correlation was found between age, clinical condition, site and extent of subarachnoid hemorrhage and either the occurrence or severity of arrhythmias. The results of our study indicate an extremely high incidence of arrhythmias, sometimes serious, in subarachnoid hemorrhage, especially in the first 48 hours after hemorrhage. Continuous electrocardiographic monitoring is therefore mandatory.


Assuntos
Arritmias Cardíacas/diagnóstico , Eletrocardiografia , Hemorragia Subaracnóidea/complicações , Adolescente , Adulto , Idoso , Arritmias Cardíacas/sangue , Arritmias Cardíacas/etiologia , Feminino , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Potássio/sangue , Estudos Prospectivos , Hemorragia Subaracnóidea/sangue , Fatores de Tempo
8.
Am J Cardiol ; 69(14): 1166-70, 1992 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-1575186

RESUMO

To evaluate the prevalence and prognostic role of silent coronary artery disease (CAD) in patients with symptomatic high-grade carotid stenosis (70 to 99%) undergoing carotid endarterectomy, and with neither history nor symptoms of CAD, 106 patients (76 men, 30 women, mean age 58.7 years [range 42 to 71]) with recent cerebral ischemia were prospectively studied. Patients were stratified as to the presence (n = 27, 25%) or absence (n = 79, 75%) of silent CAD defined by concordant abnormal exercise electrocardiographic testing and thallium-201 myocardial scintigraphy. The male sex, the severity of the symptomatic carotid lesion (greater than 90%), and the coexistence of contralateral carotid disease identified patients with higher probability of coexisting CAD. The 106 patients underwent 121 operations (bilateral in 15). In the perioperative period, no deaths or cardiac events occurred, 1 patient suffered a recurrent stroke and 3 had a transient ischemic attack. During a mean follow-up period of 5.4 years, 9 patients died (1.7%/year): fatal myocardial infarction occurred in 5 (all in the silent CAD group), cancer in 3 and vertebrobasilar stroke in 1. Nonfatal events occurred in 9 patients: myocardial infarction in 1 (without silent CAD), unstable angina in 3 (with silent CAD), and cerebral ischemic attacks in 5. After 7 years, the Kaplan-Meier estimated survival free from coronary events was 51% in patients with silent CAD, and 98% in patients without CAD (p less than 0.01). In conclusion, among patients with symptomatic high-grade carotid stenosis undergoing carotid endarterectomy, even in absence of history or symptoms of CAD, a silent CAD is detectable in one fourth of the patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Estenose das Carótidas/complicações , Estenose das Carótidas/cirurgia , Doença das Coronárias/complicações , Endarterectomia das Carótidas , Adulto , Idoso , Distribuição de Qui-Quadrado , Doença das Coronárias/diagnóstico , Doença das Coronárias/epidemiologia , Teste de Esforço , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Análise de Sobrevida , Radioisótopos de Tálio
9.
Chest ; 101(4): 1050-5, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1532548

RESUMO

The purpose of this study was to compare the early postoperative effects of heart and heart-lung transplantation on the secretion of atrial natriuretic peptide (alpha-ANP), renin, aldosterone, and vasopressin. This was carried out from the first to the eighth postoperative day in ten heart and five heart-lung recipients. The changes in the release of these hormones were similar in both groups. Vasopressin release remained stable while that of the renin-angiotensin-aldosterone system progressively returned to more normal levels. Grafted heart tissue was capable of high alpha-ANP release early on in both heart and in heart-lung recipients. This sustained alpha-ANP release was not a function of the resulting overall atrial tissue mass. Our findings suggest that it might be the consequence of an intrinsic hypersecretion of alpha-ANP resulting from the loss of normal heart innervation occurring in both heart and heart-lung transplantation.


Assuntos
Pressão Sanguínea/fisiologia , Glândulas Endócrinas/metabolismo , Transplante de Coração/fisiologia , Transplante de Coração-Pulmão/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Adulto , Aldosterona/sangue , Fator Natriurético Atrial/sangue , Compartimentos de Líquidos Corporais/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Renina/sangue , Vasopressinas/sangue
10.
J Heart Lung Transplant ; 16(10): 994-1000, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9361241

RESUMO

BACKGROUND: Focal myocardial necrosis reported in patients who died of brain lesions and in donor hearts soon after insertion has been attributed to catecholamine-related injury induced before operation, or in the perioperative period. Interpretation of the morphofunctional type of myocardial injury observed and its quantification may help understand both its pathophysiology and clinical relevance. METHODS: In 27 patients without heart disease who died of intracranial brain hemorrhage after berry aneurysm rupture, terminal clinical signs were correlated with the presence of absence of myocardial injury. All hearts were systematically examined, and the total histologic area was measured in square millimeters, with both the number of foci and myocardial cells showing necrosis, normalized to 100 mm2. Forty-five cases of fatal head trauma (26 "instantaneous" and 19 "rapid" deaths) in normal subjects and 38 cases of acquired immunodeficiency syndrome with (14 cases) or without (24 cases) severe brain damage were used as control subjects. RESULTS: Contraction band necrosis was the only form of myocardial necrosis found in 89% of patients with acute brain hemorrhage. Its extent was 26 +/- 34 foci and 67 +/- 104 necrotic myocardial cells x 100 mm2. In patients with acquired immunodeficiency syndrome, its frequency was 58% in those without and 78.5% with severe brain lesions, with foci and myocardial cell values of 1 +/- 1.5 and 10 +/- 22 and 7 +/- 16 and 17 +/- 32, respectively. In head trauma cases with instantaneous death, the frequency was 4% (one case only with foci 0.5 and myocardial cells 35), whereas with a rapid death it was 40% (foci 12 +/- 18 and myocardial cells 21 +/- 33). CONCLUSIONS: The observed myocardial injury was present in all groups examined, being maximal in patients with intracranial brain hemorrhage with longer survival and minimal in patients with head trauma who died instantaneously. In this setting, this lesion is typical of catecholamine myotoxicity and may express a sympathetic overstimulation either in the agonal period and independent of therapy or be caused by brain injury, especially intracranial brain hemorrhage. However, the extent of myocardial injury observed was minimal and should not jeopardize cardiac function if hearts from such subjects are transplanted.


Assuntos
Encefalopatias/complicações , Transplante de Coração/patologia , Isquemia Miocárdica/etiologia , Complexo AIDS Demência/complicações , Complexo AIDS Demência/fisiopatologia , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/fisiopatologia , Adulto , Fatores Etários , Idoso , Aneurisma Roto/complicações , Aneurisma Roto/fisiopatologia , Abscesso Encefálico/complicações , Abscesso Encefálico/fisiopatologia , Encefalopatias/fisiopatologia , Catecolaminas/fisiologia , Causas de Morte , Hemorragia Cerebral/complicações , Hemorragia Cerebral/fisiopatologia , Traumatismos Craniocerebrais/complicações , Traumatismos Craniocerebrais/fisiopatologia , Feminino , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/fisiopatologia , Masculino , Meningoencefalite/complicações , Meningoencefalite/fisiopatologia , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Isquemia Miocárdica/patologia , Isquemia Miocárdica/fisiopatologia , Miocárdio/patologia , Necrose , Tamanho do Órgão , Fatores Sexuais , Simpatomiméticos/farmacologia
11.
J Heart Lung Transplant ; 12(6 Pt 1): 1001-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8312300

RESUMO

The purpose of this study was to investigate the changes in endocrine control of blood pressure and electrolyte homeostasis during the early postoperative period after heart transplantation. Dynamic testing using volume-expansion to increase cardiac filling pressures was performed to determine changes in alpha atrial natriuretic peptide, renin, aldosterone, and vasopressin secretion in response to a physiologic stimulus. Volume expansion was performed on five heart transplant patients each day from postoperative day 1 to postoperative day 5. Alpha atrial natriuretic peptide, renin, aldosterone, and vasopressin plasma levels were assessed by radioimmunoassay before and during the 6 hours after the beginning of infusion. No significant changes in the secretion of any of the various hormones studied were found after volume expansion. Moreover, we found that heart transplant recipients were unable to increase water and sodium renal excretion after volume expansion. The physiologic decrease in vasopressin release after volume expansion appears to be altered by graft denervation. Furthermore, persistently elevated alpha atrial natriuretic peptide plasma levels at rest despite improved patient hemodynamic status and the absence of enhanced hormone secretion after a physiologic stimulus are in favor of an intrinsic hypersecretion of this hormone. Moreover, the absence of an appropriate renal response could be a major consequence of both the lack of further increased alpha atrial natriuretic peptide secretion and the heart denervation resulting from transplantation. This blunted renal response should be taken into account when managing patients in the early period after transplantation.


Assuntos
Transplante de Coração , Hormônios/sangue , Volume Plasmático , Aldosterona/sangue , Fator Natriurético Atrial/sangue , Hemodinâmica , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Renina/sangue , Vasopressinas/sangue
12.
J Heart Lung Transplant ; 13(4): 661-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7947883

RESUMO

Early graft failure accounts for a substantial portion of the mortality after heart transplantation. This factor underscores the need for the development of reliable methods for predicting graft performance and thus ensuring optimal clinical outcome. The aim of this study was to describe the link between myocardial metabolism evaluated throughout preservation with the use of phosphorus 31-nuclear magnetic resonance spectroscopy and ventricular contractility after reperfusion. Thirteen pig hearts were excised and preserved from 3 to 12 hours with clinical techniques. During preservation the hearts underwent phosphorus 31-nuclear magnetic resonance spectroscopy. After reperfusion, left ventricular contractility was evaluated with an isolated heart model undergoing isovolumetric contraction. Throughout storage, beta-adenosine triphosphate remained stable and intracellular pH and phosphocreatine decreased exponentially, whereas inorganic phosphate increased exponentially. Intracellular pH, phosphocreatine, inorganic phosphates measured at the onset of preservation, and intracellular pH and phosphocreatine measured at the end of preservation correlated significantly with the left ventricular contractility after reperfusion. We conclude that the metabolic state of myocardium at excision is especially important and that phosphorus 31-nuclear magnetic resonance evaluation of the heart during preservation appears to provide reliable indexes for predicting subsequent ventricular contractility after reperfusion.


Assuntos
Transplante de Coração , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Preservação de Órgãos , Fosfatos/metabolismo , Função Ventricular Esquerda/fisiologia , Animais , Bicarbonatos , Cloreto de Cálcio , Soluções Cardioplégicas , Metabolismo Energético , Concentração de Íons de Hidrogênio , Hipotermia Induzida , Magnésio , Espectroscopia de Ressonância Magnética , Reperfusão Miocárdica , Cloreto de Potássio , Cloreto de Sódio , Suínos
13.
Regul Pept ; 49(1): 81-90, 1993 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-8278636

RESUMO

The purpose of this study was to investigate the feasibility of cardiac microdialysis for the in vivo estimation of cardiac interstitial peptide concentrations, and, to determine the changes in neuropeptide Y release in myocardial tissue during experimental brain death in pigs. Using a specifically designed concentric flexible probe, perfused with Ringer solution containing 0.5% of bovine serum albumin at a flow rate of 2 microliters/min, allowed us to obtain a 23 +/- 2% relative recovery rate in vitro. Based on these in vitro recovery data, a regional study of the kinetics of interstitial NPY levels following brain death was obtained by monitoring the changes in NPY dialysate levels recorded from dialysis probes implanted into the right and left ventricular walls of the beating heart in vivo. Basal dialysate NPY levels determined by radioimmunoassay were of 95.2 +/- 7.0 and 93.2 +/- 9.1 pmol/l in left and right ventricle, respectively. Brain death was followed by a sustained 2 h increase in NPY dialysate levels in both ventricles (peak levels: 173.2 +/- 30.9 pmol/l in left ventricle, and 149.7 +/- 23.9 pmol/l in right ventricle), which then returned to control levels. We conclude that cardiac microdialysis is a simple and promising new tool for evaluating the role of peptides in cardiovascular regulation.


Assuntos
Morte Encefálica/metabolismo , Microdiálise/métodos , Miocárdio/metabolismo , Neuropeptídeo Y/metabolismo , Animais , Espaço Extracelular/química , Hemodinâmica , Radioimunoensaio , Suínos
14.
Ann Thorac Surg ; 60(6): 1729-34, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8787471

RESUMO

BACKGROUND: Because of problems concerning the functional quality of heart transplants, more and more interest has been focused on the physiologic changes occurring during brain death, one of the major possible contributing factors to the myocardial alterations. METHODS: The aim of this study was to describe the link between acute experimental brain death and myocardial metabolism. This was achieved by in vivo 3-hour hemodynamic and biological (myocardial lactate production) studies and then in vitro 6-hour phosphorus-31 nuclear magnetic resonance spectroscopy. Two groups of pigs were involved in the study: group I (n = 10) as control and group II (n = 10) as brain-dead animals. RESULTS: Within the first hour, we observed a strong increase in myocardial activity associated with the onset of myocardial lactate production, lasting 2 hours and corresponding to a myocardial anaerobic metabolism period. Despite the apparent normalization before excision of the hearts, phosphorus-31 nuclear magnetic resonance spectroscopy revealed a significant decrease in adenosine triphosphate levels in group II when compared with group I. CONCLUSIONS: We conclude that, in our study, acute experimental brain death is associated with an early and transient period of myocardial anaerobic metabolism and adenosine triphosphate consumption. These myocardial consequences of brain death could partially explain some observations of heart graft dysfunction.


Assuntos
Morte Encefálica , Hemodinâmica , Lactatos/metabolismo , Miocárdio/metabolismo , Trifosfato de Adenosina/metabolismo , Anaerobiose , Animais , Pressão Sanguínea , Frequência Cardíaca , Transplante de Coração , Espectroscopia de Ressonância Magnética , Suínos
15.
Ann Thorac Surg ; 61(1): 227-9, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8561567

RESUMO

In chronic pulmonary vascular thrombotic disease, pulmonary thromboendarterectomy has proved to be effective in reducing pulmonary hypertension and improving gas exchange. However, persistent pulmonary hypertension and unrelenting reperfusion edema are the main causes of death. We report a case of pulmonary thromboendarterectomy followed by an immediate unfavorable postoperative course with acute and persistent pulmonary hypertension, gas exchange impairment, and heart dysfunction. In this particular case, inhaled nitric oxide was successfully administered.


Assuntos
Endarterectomia , Hipertensão Pulmonar/tratamento farmacológico , Óxido Nítrico/administração & dosagem , Artéria Pulmonar/cirurgia , Embolia Pulmonar/cirurgia , Administração por Inalação , Adulto , Doença Crônica , Hemodinâmica , Humanos , Hipertensão Pulmonar/etiologia , Masculino , Complicações Pós-Operatórias/terapia , Edema Pulmonar/etiologia , Edema Pulmonar/terapia , Embolia Pulmonar/fisiopatologia , Troca Gasosa Pulmonar
16.
Neurol Res ; 14(2 Suppl): 112-7, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1355863

RESUMO

The cardiologic evaluation of patients with cerebral ischaemia should be aimed at: (1) identifying potential cardiac sources for cerebral emboli, (2) detecting a coexisting ischaemic heart disease, even asymptomatic. The present data concerns a ten-year experience of a systematic cardiologic evaluation of patients admitted to the 1st Division of Neurosurgery, Bellaria Hospital, Bologna, Italy, for cerebral ischaemia. A two-dimensional echocardiography was carried out in 344 consecutive patients (mean age 53 years), cardiac abnormalities were observed in 92 (28%) out of the 328 cases with technically adequate examination, embologenic lesions in 57 (17%). In 18 cases the cardiac lesion was unknown before the cerebral event. An exercise ECG testing was carried out in 322 patients (mean age 56 years), resulting in abnormal in 69 out of the 258 with adequate examination (17%). A subsequent exercise 201Tl myocardial scintigraphy confirmed the presence of ischaemic heart disease in 58 cases. Among patients unable to perform an adequate exercise, a dipyridamole 201Tl myocardial scintigraphy was performed in 38 cases showing perfusional defects in 23 (60%), while a dipyridamole echocardiography was performed in 25 cases showing wall motion abnormalities in 9 (36%). A 24-h Holter monitoring was performed in 65 cases: arrhythmias were detected in 27 patients (41%), but a correlation with the cerebral event was suggested only in 3 cases with atrial fibrillation. According to our experience patients with recent ischaemia should be submitted to the following non-invasive cardiologic screening: (1) exercise ECG testing followed, if abnormal or indeterminant, by 201Tl myocardial scintigraphy in all patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Isquemia Encefálica/fisiopatologia , Doença das Coronárias/diagnóstico , Doença das Coronárias/fisiopatologia , Cardiopatias/diagnóstico , Cardiopatias/fisiopatologia , Isquemia Encefálica/complicações , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/fisiopatologia , Doença das Coronárias/complicações , Dipiridamol/uso terapêutico , Ecocardiografia , Eletrocardiografia , Eletrocardiografia Ambulatorial , Teste de Esforço , Cardiopatias/complicações , Humanos , Projetos de Pesquisa , Radioisótopos de Tálio
17.
Int J Cardiol ; 18(2): 163-72, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3343072

RESUMO

Five cases (3.8%) in a series of 132 patients with spontaneous subarachnoid hemorrhage, studied by 24-hour Holter monitoring, presented with ventricular tachycardia of torsade de pointes variety. In all cases, the arrhythmias were observed within 24 hours after the bleeding. The QTc interval was prolonged more than 0.55 sec, and hypokalemia of less than 3.5 mEq/liter was present in all patients. The clinical status was not significant. Torsade de pointes occurred in comatose patients (3 cases) as well as in alert patients (2 cases). The arrhythmia was reversed by therapy in 3 patients, one of whom survived while 2 died due to cerebral damage. Our observations confirm the presence of life-threatening ventricular arrhythmias in the acute phase of subarachnoid hemorrhage. Continuous electrocardiographic monitoring is therefore advisable in view of its potential role in alerting to the need for treatment.


Assuntos
Arritmias Cardíacas/etiologia , Hemorragia Subaracnóidea/complicações , Taquicardia/etiologia , Fibrilação Ventricular/etiologia , Adulto , Idoso , Doença das Coronárias/complicações , Eletrocardiografia , Teste de Esforço , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Hipertensão/complicações , Aneurisma Intracraniano/complicações , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica
18.
Int J Cardiol ; 12(2): 243-53, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3744603

RESUMO

The absence of electrocardiographic changes during angina is an unusual occurrence. In 15 male patients with exercise-induced angina, the electrocardiogram failed to show the usual ischemic ST-T changes. The exercise thallium-201 myocardial imaging was employed as indicator of the ischemia and the results were correlated with coronary angiographic findings. The exercise thallium-201 myocardial imaging showed an exercise-induced reversible defect in 14 patients and a fixed defect in the remaining 1. Out of 15 patients, 13 had defects involving the infero-apical, posterior and postero-lateral segments. The coronary angiography, performed in all patients but 2, showed single-vessel coronary artery disease in 8 patients and double-vessel disease in 5. A significant circumflex or right coronary artery stenosis was found in all cases except 1; 2 patients had a coexistent left anterior descending coronary artery stenosis and 1 an isolated stenosis of this vessel. It is concluded that the myocardial scintigraphy is useful to assess the ischemic myocardial origin of chest pain in the absence of ST-T changes. The silence of the electrocardiogram might be due to the production of ischemia in not well explored areas, such as the inferior and posterior myocardial segments, and possibly to a smaller extension of ischemia.


Assuntos
Angina Pectoris/diagnóstico , Doença das Coronárias/diagnóstico , Eletrocardiografia , Teste de Esforço , Adulto , Idoso , Cateterismo Cardíaco , Cineangiografia , Angiografia Coronária , Humanos , Masculino , Pessoa de Meia-Idade , Radioisótopos , Tálio
19.
Int J Cardiol ; 6(6): 673-88, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6519841

RESUMO

The relative efficacy of nicardipine and nifedipine was examined in a double-blind placebo-controlled randomized crossover trial. We studied 12 patients with chronic effort angina involving reproducible angina and greater than or equal to 1.5 mm of ST-segment depression on exercise treadmill test performed before and after a 1-week control period of single-blind placebo administration. Subsequently, indistinguishably prepared nicardipine 20 mg, nifedipine 10 mg, or placebo, four times a day, was administered in a randomized double-blind crossover fashion for 3 weeks (total study period 9 weeks). Exercise treadmill test was performed at the end of each 3-week period. Both nicardipine and nifedipine significantly reduced the frequency of anginal attacks and nitroglycerin consumption. Compared with placebo both drugs caused a comparable increase of the duration of exercise, of the time to angina and to the appearance of 1.5 mm ST-segment depression (P less than 0.05 placebo versus nicardipine; P less than 0.01 placebo versus nifedipine respectively). No significant side effects were observed with either drug. We conclude that nicardipine and nifedipine produce similar hemodynamic and clinical effects in patients with stable effort angina.


Assuntos
Angina Pectoris/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Nifedipino/análogos & derivados , Nifedipino/uso terapêutico , Idoso , Bloqueadores dos Canais de Cálcio/farmacologia , Método Duplo-Cego , Esquema de Medicação , Teste de Esforço , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Nicardipino , Nifedipino/administração & dosagem , Nifedipino/farmacologia , Distribuição Aleatória , Descanso
20.
J Heart Valve Dis ; 4(2): 199-201, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8556184

RESUMO

Valvular tumors are uncommon and usually benign lesions, discovered accidentally or when neurological or cardiological complications occur. We report a case of mitral valve papillary fibroelastoma measuring less than 1 cm and revealed by stroke. Transesophageal echocardiography was the best method to establish the diagnosis as it provided higher discriminative power than the transthoracic echocardiography or nuclear magnetic resonance. The embolic risks justify the surgical treatment of these lesions while anticoagulation therapy can be suggested as a substitute to surgery for the high risk patients.


Assuntos
Fibroma/complicações , Neoplasias Cardíacas/complicações , Embolia e Trombose Intracraniana/etiologia , Adulto , Feminino , Fibroma/cirurgia , Neoplasias Cardíacas/cirurgia , Humanos , Embolia e Trombose Intracraniana/cirurgia , Valva Mitral
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