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1.
East Mediterr Health J ; 19(10): 861-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24313150

RESUMO

As future physicians capable of controlling tobacco dependence in the population, medical students are considered a main target for tobacco control interventions. This cross-sectional study reported on the prevalence of tobacco use (cigarettes and waterpipes) and associated knowledge and behaviour among 6th-year medical students in 2009-2010 from 6 medical schools in Lebanon. The self-administered questionnaire based on the Global Health Professional Survey (GHPSS) core questions also enquired about training in tobacco cessation approaches. All enrolled students were asked to participate; the response rate was 191/354 (54.3%). The prevalence of tobacco use was 26.3% for cigarettes and 29.5% for waterpipes. Smoking waterpipes was the only significant predictor for cigarette smoking and there was no difference by sex and socioeconomic status. A minority reported ever receiving any formal training in treatment approaches for tobacco dependence. Medical schools should include tobacco dependence treatment training programmes in their curriculum and discourage tobacco use.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Fumar/epidemiologia , Estudantes de Medicina/estatística & dados numéricos , Adulto , Estudos Transversais , Feminino , Humanos , Líbano/epidemiologia , Masculino , Prevalência , Fumar/psicologia , Fatores Socioeconômicos , Estudantes de Medicina/psicologia , Tabagismo/epidemiologia , Tabagismo/terapia
2.
Diabetes Obes Metab ; 15(6): 558-63, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23350696

RESUMO

AIMS: Glycaemic variability (GV) is associated with mortality in acutely ill patients, but the mechanism is unknown. The objective of this study is to determine whether common approaches to insulin therapy have distinct effects on GV and autonomic tone. METHODS: Hospitalized patients with diabetes were randomized to short-term intravenous (IV) or physiologic subcutaneous (SQ) insulin. Heart rate variability (HRV) and cardiac impedance (pre-ejection period, PEP) were used to estimate parasympathetic and sympathetic tone, respectively. GV was measured using a continuous glucose monitor. RESULTS: Mean glucose tended to be lower initially in the SQ group (N = 16) compared with the IV group (N = 17) on day 1 (10.5 vs. 8.6 mmol/l, p = 0.05), but became non-significant during the transition off of the infusion. There was no difference in glycaemic lability index (GLI), continuous overlapping net glycaemic action (CONGA) or coefficient of variation (CV) on day 1, but by day 2, these measures were higher in the IV group (p < 0.05 for all). PEP was higher in the SQ group during (110 vs. 123 ms, p = 0.02) and after the intervention (104 vs. 126 ms, p = 0.004). Hypoglycaemia was similar in both groups. There were only small differences in HRV. Post-treatment PEP was inversely correlated with log GLI (r = -0.41, p = 0.03) but not other measures. CONCLUSIONS: Short-term IV insulin is associated with an increase in multiple GV measures compared with optimal SQ insulin. However, GLI was the only predictor of PEP. Further research is needed to determine if interventions that minimize GV improve outcomes in the hospital.


Assuntos
Sistema Nervoso Autônomo/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Angiopatias Diabéticas/tratamento farmacológico , Hipoglicemia/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Monitorização Fisiológica/métodos , Sistema Nervoso Autônomo/fisiopatologia , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/fisiopatologia , Esquema de Medicação , Feminino , Hemoglobinas Glicadas/metabolismo , Índice Glicêmico , Frequência Cardíaca , Hospitalização , Humanos , Hipoglicemia/sangue , Hipoglicemia/fisiopatologia , Infusões Intravenosas , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Projetos Piloto
3.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-118578

RESUMO

As future physicians capable of controlling tobacco dependence in the population, medical students are considered a main target for tobacco control interventions. This cross-sectional study reported on the prevalence of tobacco use [cigarettes and waterpipes] and associated knowledge and behaviour among 6th-year medical students in 2009-2010 from 6 medical schools in Lebanon. The self-administered questionnaire based on the Global Health Professional Survey [GHPSS] core questions also enquired about training in tobacco cessation approaches. All enrolled students were asked to participate; the response rate was 191/354 [54.3%]. The prevalence of tobacco use was 26.3% for cigarettes and 29.5% for waterpipes. Smoking waterpipes was the only significant predictor for cigarette smoking and there was no difference by sex and socioeconomic status. A minority reported ever receiving any formal training in treatment approaches for tobacco dependence. Medical schools should include tobacco dependence treatment training programmes in their curriculum and discourage tobacco use

4.
Mol Hum Reprod ; 15(10): 687-92, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19643817

RESUMO

The aim of this study was to investigate whether peroxisome proliferator-activated receptor (PPAR)-gamma activation has an effect on the attachment of endometrial cells to peritoneal mesothelial cells in a well-established in vitro model of the early endometriotic lesion. The endometrial epithelial cell line EM42 and mesothelial cell line LP9 were used for this study. EM42 cells, LP9 cells or both were treated with the PPAR-gamma agonist ciglitazone (CTZ) at varying concentrations (10, 20 and 40 microM) x 48 h with subsequent co-culture of EM42 and LP9 cells. The rate of EM42 attachment and invasion through LP9 cells was then assessed and compared with control (EM42 and LP9 cells co-cultured without prior treatment with CTZ). Next, attachment of CTZ-treated and untreated EM42 cells to hyaluronic acid (HA), a cell adhesion molecule (CAM) on peritoneal mesothelial cells, were assessed. Although there was no difference in EM42 attachment when LP9 cells alone were treated with CTZ, treatment of EM42 cells with 40 microM CTZ decreased EM42 attachment to LP9 cells by 27% (P < 0.01). Treatment of both EM42 and LP9 cells with 40 microM CTZ decreased EM42 attachment to LP9 by 37% (P < 0.01). Treatment of EM42 cells with 40 microM CTZ decreased attachment to HA by 66% (P = 0.056). CTZ did not decrease invasion of EM42 cells through the LP9 monolayer. CTZ may inhibit EM42 cell proliferation. In conclusion, CTZ significantly decreased EM42 attachment to LP9 cells and HA in an in vitro model of the early endometriotic lesion.


Assuntos
Endometriose/patologia , Endométrio/patologia , PPAR gama/agonistas , Tiazolidinedionas/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos
5.
Clin Pharmacol Ther ; 85(1): 36-44, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18946466

RESUMO

Genetic variants of ACE are suspected risk factors in cardiovascular disease, but the alleles responsible for the variations remain unidentified. To search for regulatory polymorphisms, allelic angiotensin I-converting enzyme (ACE) mRNA expression was measured in 65 heart tissues, followed by genotype scanning of the ACE locus. Marked allelic expression imbalance (AEI) detected in five African-American subjects was associated with single-nucleotide polymorphisms (SNPs) (rs7213516, rs7214530, and rs4290) residing in conserved regions 2-3 kb upstream of ACE. Moreover, each of the SNPs affected transcription in reporter gene assays. SNPs rs4290 and rs7213516 were tested for associations with adverse cardiovascular outcomes in hypertensive patients with coronary disease (International Verapamil SR Trandolapril Study Genetic Substudy (INVEST-GENES), n = 1,032). Both SNPs were associated with adverse cardiovascular outcomes, largely attributable to nonfatal myocardial infarction in African Americans, showing an odds ratio of 6.16 (2.43-15.60) (P < 0.0001) for rs7213516. The high allele frequency in African Americans (16%) compared to Hispanics (4%) and Caucasians (<1%) suggests that these alleles contribute to variation between populations in cardiovascular risk and treatment outcomes.


Assuntos
Negro ou Afro-Americano/genética , Genes Reporter/genética , Variação Genética/genética , Hipertensão/genética , Peptidil Dipeptidase A/genética , Polimorfismo Genético/genética , Polimorfismo de Nucleotídeo Único/genética , RNA Mensageiro/genética , Idoso , Anti-Hipertensivos/uso terapêutico , Estudos de Casos e Controles , Doença das Coronárias/complicações , Etnicidade/genética , Feminino , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Masculino , Peptidil Dipeptidase A/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco
7.
Am J Cardiol ; 86(10): 1148-51, A9, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11074219

RESUMO

Myocardial histology of cardiac allografts differed between short-term (<5 years) and long-term (>5 years) survivors after transplantation. These differences may partially be attributable to a higher prevalence of systemic hypertension and allograft rejection in the short-term survivors, affecting hemodynamics and allograft function.


Assuntos
Fibrose Endomiocárdica/etiologia , Fibrose Endomiocárdica/patologia , Transplante de Coração/efeitos adversos , Transplante de Coração/mortalidade , Ventrículos do Coração/patologia , Adulto , Análise de Variância , Biópsia , Causas de Morte , Distribuição de Qui-Quadrado , Fibrose Endomiocárdica/mortalidade , Feminino , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Humanos , Hipertensão/etiologia , Hipertensão/patologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Fatores de Tempo , Transplante Homólogo
8.
Fertil Steril ; 74(4): 813-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11020529

RESUMO

OBJECTIVE: To examine the impact of implementation of a new fee for continued storage of cryopreserved embryos on the rate of requests for disposal of embryos. DESIGN: Retrospective cohort study. SETTING: A university-based assisted reproduction program. PATIENT(S): All patients with cryopreserved embryos. INTERVENTION(S): Implementation of a semiannual embryo storage fee of $100 to cover administrative and laboratory costs. MAIN OUTCOME MEASURE(S): The number of embryo disposal requests before and after implementation of the embryo storage fee was compared in relation to the activity of the cryopreserved embryo program as measured by number of frozen embryo transfers. RESULT(S): Annual requests for embryo disposal from 1992 through 1997 ranged from zero to three, which represented 0-5% of the annual frozen embryo program activity. In contrast, a significantly higher number of disposal requests (10, representing 18% of program activity) were received in 1998. CONCLUSION(S): Fees for storage of cryopreserved embryos seem to influence patients' decisions about disposal of cryopreserved embryos.


Assuntos
Comportamento de Escolha , Criopreservação/economia , Embrião de Mamíferos , Fertilização in vitro , Estudos de Coortes , Transferência Embrionária , Humanos , Estudos Retrospectivos
9.
J Am Coll Cardiol ; 36(2): 509-16, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10933365

RESUMO

OBJECTIVES: We hypothesized that plasma factors important for the development of atherosclerosis play a major role in the occurrence of cardiac allograft vasculopathy (CAV). BACKGROUND: Cardiac allograft vasculopathy is a major cause of death among heart transplant recipients, has a poorly understood pathogenesis and has similarities to atherosclerotic coronary disease. METHODS: The study population consisted of 93 postcardiac transplant recipients. Thirty-one patients with congestive heart failure (CHF) and 18 healthy individuals served as control subjects. Posttransplant coronary anatomy was evaluated by angiography and intravascular ultrasound. Laboratory analyses of lipids, homocysteine, vitamin B12 and folate, fibrinogen, von Willebrand factor antigen (vWFAg) and renin were obtained on all participants. RESULTS: Posttransplant patients were found to have elevated serum triglycerides, total cholesterol/ high-density lipoprotein cholesterol ratio, lipoprotein (a), homocysteine, vWFAg, fibrinogen and renin and lower high-density lipoprotein cholesterol. Most of these laboratory atherogenic factors were also elevated to a similar degree in the CHF control population. Although most atherogenic markers were elevated, there was little correlation with CAV severity. Cardiac allograft vasculopathy severity varied with time after transplantation, 3-hydroxy-methyl-glutaryl-coenzyme A reductase inhibitor use and prior cytomegalovirus infection. Even within the normal range, lower RBC folate levels were associated with increased severity of CAV. CONCLUSIONS: The posttransplant course is associated with increased clinical and laboratory atherogenic factors, some of which likely contribute to the severity of coronary vasculopathy. Compared with normal control subjects, many of these markers are already increased in pretransplant CHF patients with or without occlusive coronary artery disease.


Assuntos
Arteriosclerose/sangue , Insuficiência Cardíaca/sangue , Transplante de Coração/efeitos adversos , Adulto , Biomarcadores/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Transversais , Feminino , Insuficiência Cardíaca/cirurgia , Homocisteína/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Homólogo
11.
Cardiology ; 93(1-2): 56-69, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10894908

RESUMO

Congestive heart failure (CHF), one of the few cardiovascular conditions increasing in incidence and prevalence, is characterized by high morbidity and mortality. Up to 50% of the mortality is attributable to dysrhythmic sudden death. Risk stratification to identify those most susceptible to sudden death remains imperfect. The advances in CHF therapeutics and management over the past 16 years have had a favorable impact on CHF mortality including sudden death. The role of amiodarone and implantable cardioverter-defibrillator intervention is evolving and discussed in the context of current CHF management and available trials.


Assuntos
Antiarrítmicos/uso terapêutico , Cardiotônicos/uso terapêutico , Morte Súbita Cardíaca/etiologia , Diuréticos/uso terapêutico , Cardioversão Elétrica , Insuficiência Cardíaca/mortalidade , Taquicardia Ventricular/etiologia , Morte Súbita Cardíaca/prevenção & controle , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/terapia , Humanos , Prognóstico , Taxa de Sobrevida , Taquicardia Ventricular/mortalidade , Taquicardia Ventricular/terapia
12.
Am Heart J ; 140(1): 34-42, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10874261

RESUMO

BACKGROUND: Administration of angiotensin-converting enzyme (ACE) inhibitors to patients with congestive heart failure has been shown to increase parasympathetic tone as indicated by increases in high-frequency heart rate variability. The mechanism for this effect, including its relation to changes in baroreflex activity, blood pressure variability, and suppression of ACE activity, remains undefined. This study was designed to test the relation of these variables, which may govern changes in autonomic activity, to the previously described increase in parasympathetic tone. METHODS: Seven patients with heart failure received a 3-hour infusion of the ACE inhibitor enalaprilat. Hemodynamic variables and parameters of heart rate and blood pressure variability, baroreflex gain derived from the interaction of heart rate and blood pressure variability, and serum ACE activity were measured during and after the infusion. Measures of heart rate and blood pressure variability were also compared against a historic control group. RESULTS: Serum ACE activity was significantly suppressed throughout and after enalaprilat infusion. Hemodynamic measures did not change other than a small decline in right atrial and pulmonary capillary wedge pressures. Parasympathetic tone showed an initial significant increase with a peak at 2 hours but then declined below baseline 8 hours after initiation of enalaprilat infusion. Sympathetically influenced low-frequency heart rate variability was significantly increased above baseline in the enalaprilat treatment group 8 hours after initiation of the infusion. Baroreflex gain showed a significant trend to an increase with the maximum value coinciding with the peak in parasympathetic tone. There was no change in blood pressure variability in the enalaprilat group and no change in baroreflex gain, heart rate variability, or blood pressure variability in the control group. CONCLUSIONS: Parasympathetic tone and baroreflex gain increased with parenteral administration of an ACE inhibitor but subsequently decreased below baseline values despite continued suppression of serum ACE activity. The dissociation between ACE suppression and autonomic response to ACE inhibition indicates that enzyme systems not reflected by plasma ACE activity or independent from the classic pathways of angiotensin formation contribute to the regulation of the autonomic response to ACE inhibition in patients with heart failure. The absence of significant change in hemodynamic variables or in blood pressure variability indicates that these autonomic changes are not an indirect reflex response to ACE inhibitor-induced vasodilation or hemodynamic baroreceptor stimulation.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Barorreflexo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Enalaprilato/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Frequência Cardíaca/efeitos dos fármacos , Adulto , Idoso , Análise de Variância , Inibidores da Enzima Conversora de Angiotensina/farmacocinética , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/fisiologia , Barorreflexo/fisiologia , Esquema de Medicação , Enalaprilato/farmacocinética , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/fisiologia , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Probabilidade , Valores de Referência
13.
J Am Coll Cardiol ; 32(3): 704-10, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9741515

RESUMO

OBJECTIVES: This study was performed to determine the degree and time course over 6 years of cardiomyocyte hypertrophy and myocardial fibrosis of the cardiac allograft in transplanted patients. BACKGROUND: Diastolic dysfunction and to a certain extent systolic dysfunction are common cardiac findings after heart transplantation. The development of posttransplant cardiomyocyte hypertrophy and myocardial fibrosis likely contributes to these derangements. METHODS: Cardiomyocyte diameter and percent fibrosis were determined in serial endomyocardial biopsy specimens obtained from 1 month up to 6 years following heart transplantation in 50 patients. Endomyocardial biopsy specimens from 40 patients with primary dilated cardiomyopathy and 11 normal subjects were similarly analyzed for control data. Analyses were performed in a blinded format using a validated computerized image analysis system (Optimas 5.2). RESULTS: Early (1 month) cardiomyocyte enlargement decreased to the smallest diameter 6 months posttransplant, but thereafter progressively increased by 10% to 20% over the subsequent 5- to 6-year period. Although not statistically established, principal stimuli may include a discrepancy in body size (recipient > donor), coronary allograft vasculopathy and posttransplant systemic hypertension. Percent myocardial fibrosis rose early (1 to 2 months) posttransplant and thereafter remained at the same modest level of severity. CONCLUSIONS: Cardiomyocyte diameter of the transplanted heart gradually increases over time, while percent myocardial fibrosis rises early and remains in a modestly elevated plateau after 2 months posttransplant. These histostructural changes likely contribute to the hemodynamic and cardiac functional alterations commonly observed posttransplant.


Assuntos
Cardiomiopatia Hipertrófica/patologia , Fibrose Endomiocárdica/patologia , Transplante de Coração/patologia , Complicações Pós-Operatórias/patologia , Adolescente , Adulto , Biópsia , Criança , Diástole/fisiologia , Endocárdio/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Miocárdio/patologia , Fatores de Risco , Sístole/fisiologia
14.
Prog Cardiovasc Dis ; 41(3): 207-24, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9872607

RESUMO

Parenterally administered positive inotropic agents remain an important component of the therapeutics of cardiac dysfunction and failure. Dobutamine, a catechol, remains the prototype of this drug group, but recently has been joined by the phosphodiesterase III inhibitor, milrinone. Compared with dobutamine, milrinone has greater vasodilating-unloading properties. The catecholamine, dopamine, is often used as a parenteral positive inotrope; but at moderate to high dose, it evokes considerable systemic vasoconstriction. At lower doses, dopamine appears to augment renal function. Levosimendan and toborinone, new compounds with several mechanisms of action, are under active clinical investigation and review for approval. Parenteral positive inotropic therapy is indicated for short-term (hours to days) treatment of cardiovascular decompensation secondary to ventricular systolic dysfunction, low-output heart failure. More prolonged or continuous infusion of one of these agents may be necessary as a "pharmacologic bridge" to cardiac transplantation, another definitive intervention, or more advanced, intense medical therapy. An occasional patient will require a continuous infusion via indwelling venous catheter and portable pump, simply to be able to be discharged from the hospital setting and function in the home environment. Intermittent parenteral inotropic therapy for chronic heart failure has provoked considerable controversy and passion among cardiologists and heart failure specialists; an attempt is made to present this topic in an objective manner.


Assuntos
Cardiotônicos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Cardiotônicos/farmacologia , Dobutamina/farmacologia , Dobutamina/uso terapêutico , Dopamina/uso terapêutico , Tolerância ao Exercício/efeitos dos fármacos , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Humanos , Infusões Intravenosas , Milrinona/uso terapêutico , Inibidores de Fosfodiesterase/uso terapêutico
15.
J Card Fail ; 3(2): 105-11; discussion 113-6, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9220310

RESUMO

METHODS AND RESULTS: Over an 18-month period, the patients on the heart transplantation waiting list at our institution were evaluated to determine if continued listing was appropriate. Ten patients were removed because of significant improvement in clinical status and exercise capacity (n = 9) or because of criteria violation (n = 1). Four of these patients died suddenly and unexpectedly within 4 months of delisting, resulting in a 6-month survival of 60% for the patients removed. During the same period, the 6-month survival for newly listed patients (n = 10) was 80% and that for newly transplanted patients (n = 13) was 92%. An elevated pulmonary capillary wedge pressure (> or = 18 mmHg) was the only clinical or laboratory feature that appeared to distinguish the four patients who died suddenly following delisting. CONCLUSION: The results of this preliminary study suggest that removal of a patient from a heart transplant waiting list may represent a risk for sudden death, particularly in patients with elevated ventricular filling pressures, irrespective of otherwise favorable clinical status and exercise performance.


Assuntos
Morte Súbita Cardíaca , Transplante de Coração , Obtenção de Tecidos e Órgãos , Listas de Espera , Adulto , Idoso , Feminino , Cardiopatias/fisiopatologia , Cardiopatias/cirurgia , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Ohio , Seleção de Pacientes , Pressão Propulsora Pulmonar , Fatores de Risco
16.
Am J Physiol ; 271(4 Pt 2): H1635-42, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8897961

RESUMO

Positive inotropic intervention with dobutamine in patients with congestive heart failure is accompanied by complementary vascular changes, as measured by the aortic input impedance spectrum, that promote the efficient transfer of augmented myocardial contractile power. It is unknown whether this is a nonspecific response to increased ventricular contractility or is a function of the properties of the positive inotropic agent employed. Therefore, the influence of two different positive inotropic interventions, dobutamine and dopamine, on ventricular-vascular coupling was examined in 15 patients with congestive heart failure. Significant reductions in characteristic aortic impedance, wave reflection, and low-frequency impedance moduli were noted with dobutamine and were not seen with dopamine. Consequently, a significantly (P = 0.0008) greater increase in pulsatile, rather than steady-state, power output was noted with dopamine that was reflective of a significantly diminished efficiency of power transfer. Therefore, optimal transfer of increased ventricular contractile power in patients with congestive heart failure requires increases in large vessel compliance and complementary changes in ventriculoarterial coupling.


Assuntos
Cardiomiopatia Dilatada/tratamento farmacológico , Cardiotônicos/uso terapêutico , Dobutamina/uso terapêutico , Dopamina/uso terapêutico , Contração Miocárdica , Função Ventricular , Idoso , Aorta/fisiopatologia , Cardiomiopatia Dilatada/fisiopatologia , Feminino , Hemodinâmica , Homeostase , Humanos , Masculino , Pessoa de Meia-Idade , Resistência Vascular , Função Ventricular/efeitos dos fármacos
17.
Am Heart J ; 132(3): 621-7, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8800034

RESUMO

The effects of hypertension on the arterial vasculature were examined in a study group of 20 patients with newly diagnosed essential hypertension, 18 patients with chronic essential hypertension, and 32 control subjects with normal blood pressure. Left ventricular mass was determined echocardiographically. Carotid artery intimal-medial thickness was measured by means of B-mode ultrasound imaging, and carotid arterial waveforms were obtained by applanation tonometry. Compared with that in control subjects, carotid intimal-medial thickness was increased in patients with chronic hypertension (0.74 +/- 0.17 mm vs 0.61 +/- 0.15 mm in control subjects; p < 0.01) and in patients with newly diagnosed hypertension (0.66 +/- 0.12 mm vs 0.61 +/- 0.15 mm in control subjects; p < 0.05). Left ventricular mass was also higher in patients with chronic hypertension than in control subjects but was very similar between control subjects and those with newly diagnosed hypertension. Both the group with early hypertension and the group with chronic hypertension had an increased incidence of early waveform reflection evident on carotid arterial waveform examination. By multiple regression analysis, independent predictors of increased carotid intimal-medial thickness were age, systolic arterial pressure, and Murgo class of arterial waveform. Conduit arterial wall thickening precedes left ventricular remodeling in essential hypertension and is significantly related to the degree of pressure elevation and the arterial waveform contour.


Assuntos
Pressão Sanguínea , Artéria Carótida Primitiva/patologia , Hipertensão/patologia , Fatores Etários , Análise de Variância , Artéria Carótida Primitiva/fisiopatologia , Doença Crônica , Ecocardiografia , Elasticidade , Eletrocardiografia , Feminino , Previsões , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Humanos , Hipertensão/fisiopatologia , Hipertrofia , Masculino , Pessoa de Meia-Idade , Fluxo Pulsátil , Análise de Regressão , Túnica Íntima/patologia , Túnica Média/patologia
19.
J Heart Lung Transplant ; 15(4): 350-9, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8732593

RESUMO

BACKGROUND: Previous reports indicate that heart transplant recipients lack a normal nocturnal decline in blood pressure. This prospective study was designed to determine the evolution of circadian blood pressure patterns after heart transplantation. METHODS: Twenty-four-hour ambulatory blood pressure and heart rate was measured in eight heart transplant recipients early (47 +/- 35 days) and late (740 +/- 10 days) after transplantation. RESULTS: Early transplant recordings and the normal control group recordings showed similar daytime systolic blood pressure but had different nighttime systolic blood pressure (138 +/- 15 mm Hg versus 112 +/- 9 mm Hg, p = 0.0002). The percent nocturnal change in systolic blood pressure showed a nocturnal increase in blood pressure in the early recordings versus a decrease in the healthy subjects (+4 +/- 2.7 versus -13 +/- 5.4, p < 0.0001). The late recordings showed a significant decrease in the nighttime systolic blood pressure (138 +/- 15 mm Hg versus 119 +/- 7 mm Hg, p = 0.011). The percent nocturnal change in systolic blood pressure was also significantly different between the early and late recordings (+4 +/- 2.7 versus -9 +/- 9, p = 0.0082) indicating a return of a nocturnal decline in systolic blood pressure. Similar patterns in diastolic blood pressure were observed. No significant change in the percent nocturnal change in heart rate occurred (-10 +/- 4.1 versus -7 +/- 5.5). CONCLUSIONS: Prospective follow-up of this heart transplant population showed that diurnal blood pressure variation is restored in some patients; diurnal variation is not related to corticosteroids, cyclosporine, or heart rate.


Assuntos
Pressão Sanguínea/fisiologia , Ritmo Circadiano/fisiologia , Transplante de Coração/fisiologia , Anti-Hipertensivos/uso terapêutico , Monitorização Ambulatorial da Pressão Arterial , Estudos de Casos e Controles , Feminino , Frequência Cardíaca/fisiologia , Humanos , Imunossupressores/uso terapêutico , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Fatores de Tempo
20.
Am Heart J ; 131(1): 153-7, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8554003

RESUMO

Measures of heart rate variability in the frequency domain quantify autonomic activity. However, the relation of these measures to the severity of ventricular dysfunction in patients with congestive heart failure remains uncertain. We applied spectral analysis of heart rate variability to 24-hour Holter monitor recordings obtained from 20 patients with congestive heart failure who were not treated with angiotensin-converting enzyme inhibitors to determine whether significant changes in parameters of heart rate variability reflect the progression of symptoms in patients with ventricular failure. Both total and low-frequency heart rate spectral power were seen to decrease with worsening New Heart Associate (NYHA) functional class. A significant (p = 0.04) higher total power was noted in NYHA class II than in class III patients (3.0 x 10(-3) +/- 3.6 10(-4) and 2.5 x 10(-3) +/- 5.9 x 19(-4) [beats/min]2, respectively). Similarly, low-frequency heart rate spectral power was significantly (p = 0.008) higher in class II than in class III patients (1.7 x 10(-3) +/- 4.6 x 10(-4) and 1.1 x 10(-3) +/- 3.5 x 10(-4) [beats/min]2, respectively). Only the low-frequency component of the spectrum was directly correlated with left ventricular ejection fraction (LVEF) (r = 0.40) with a trend toward statistical significance (p = 0.07). Measures of heart rate variability and the changes in autonomic tone that they reflect may therefore serve as markers of the extent of disease progression in patients with congestive heart failure.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca , Quinolinas/uso terapêutico , Vasodilatadores/uso terapêutico , Adulto , Idoso , Inibidores da Enzima Conversora de Angiotensina , Sistema Nervoso Autônomo/fisiopatologia , Doença Crônica , Progressão da Doença , Método Duplo-Cego , Eletrocardiografia Ambulatorial/estatística & dados numéricos , Insuficiência Cardíaca/classificação , Humanos , Pessoa de Meia-Idade , Placebos , Processamento de Sinais Assistido por Computador , Volume Sistólico , Disfunção Ventricular/fisiopatologia , Função Ventricular Esquerda
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