Browsing by Author "Monteiro, P"
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- Abordagem Invasiva versus Conservadora nas Síndromes Coronárias Agudas sem Supradesnivelamento do Segmento ST – Contributo para o Conhecimento e Avaliação da Realidade NacionalPublication . Teixeira, R; Lourenço, C; Baptista, R; Jorge, E; António, N; Monteiro, S; Gonçalves, F; Monteiro, P; Freitas, M; Providência, LABACKGROUND: In addition to medical therapy, revascularization plays an important role in determining prognosis in the acute setting of unstable angina (UA) or non-ST elevation myocardial infarction (NSTEMI). OBJECTIVE: To compare in-hospital and medium-term outcome of an invasive versus a conservative strategy in the setting of UA/ NSTEMI. METHODS: We carried out a prospective study of 802 consecutive patients admitted to a single coronary unit between May 2004 and December 2006 with UA/NSTEMI. Patients were divided into two groups: A (n=418)--invasive strategy; B (n=384)--conservative strategy. All-cause mortality and major adverse cardiovascular events (MACE) were assessed at one year. RESULTS: Group B patients were older (73.0 [29-93] vs. 64.0 [27-86] years, p < 0.001), more frequently female and diabetic (35.9 vs. 26.0%, p = 0.002), and were more likely to have a history of myocardial infarction and heart failure. They also presented with worse renal function, lower hemoglobin levels and lower left ventricular ejection fraction (53.0 [45-59] vs. 57.0% [50-60]%, p < 0.001). In hospital mortality was significantly higher for this group (5.7 vs. 1.9%, p = 0.004). Group A had more smokers, more frequent history of percutaneous coronary intervention, higher total and LDL cholesterol, lower Killip class on admission and lower TIMI scores. They were more frequently treated with anti-platelet therapy and at discharge were more often under beta-blocker and dual anti-platelet therapy. Female gender (adjusted OR 0.46; 95% CI 0.27-0.78) and older age (adjusted OR 0.55; 95% CI 0.31-0.99), were independent predictors for a conservative strategy during hospital stay. One-year survival was higher for the invasive strategy patients (95.9% vs. 86.2%, log rank p < 0.001), as was one-year MACE-free survival (88.3% vs. 75.7%, log rank p < 0.001). According to two multivariate Cox regression analyses, opting for an invasive strategy during hospital stay conferred a 57% reduction in relative risk of death (HR 0.43; 95% CI 0.20-0.94), and a 56% reduction in relative risk of MACE (HR 0.44; 95% CI 0.26-0.77) at one year. CONCLUSIONS: Despite some imbalances between the groups, in our population an invasive strategy during hospital stay independently predicted a favorable one-year outcome.
- Amiloidose secundária e lúpus eritematoso sistémicoPublication . Monteiro, P; Abreu, P; Salvador, MJ; Malcata, ABThe authors report a clinical case of a 57 years old woman with systemic lupus erythematosus diagnosed 25 years before and secondary amyloidosis. Secondary amyloidosis can be associated with inflammatory or infectious chronic diseases, however the association with systemic lupus erythematosus is rare. We discuss the association between the two entities.
- Anti-MuSK-positive myasthenia gravis diagnosed during pregnancy: New challenges for an old diseasePublication . Neves, AR; Monteiro, P; Matos, A; Santos-Silva, IMyasthenia gravis is an autoimmune disorder affecting predominantly women in their reproductive age. The course of the disease during pregnancy is unpredictable, although it is more difficult to manage earlier in the gestation. Myasthenia gravis with antibodies against the muscle-specific receptor tyrosine kinase (anti-MuSK) has been described as a subtype of disease with more localised clinical features and a poorer response to treatment than acetylcholine receptor antibody (anti-AChR)-positive patients. Few cases have been reported in pregnant women, with deliveries being performed mainly by caesarean section. We report a successful case of vaginal delivery and describe our experience providing the first review of the management of this subtype of disease during pregnancy.
- Antioxidant and vascular effects of gliclazide in type 2 diabetic rats fed high-fat diet.Publication . Sena, CM; Louro, T; Matafome, P; Nunes, E; Monteiro, P; Seiça, RDiabetes mellitus is characterized by oxidative stress, which in turn determines endothelial dysfunction. Gliclazide is a sulphonylurea antidiabetic drug with antioxidant effects due to its azabicyclo-octyl ring. It has been reported to potentially protect the vasculature through improvements in plasma lipid levels and platelet function. We hypothesized that gliclazide has a beneficial effect on endothelial function in Goto-Kakizaki rats (GK), an animal model of type 2 diabetes fed an atherogenic diet for 4 months. We evaluated the influence of gliclazide on both metabolic and oxidative status and NO-mediated vasodilation. GKAD rats showed increased oxidative stress and impaired endothelium-dependent vasodilation. GKAD rats treated with gliclazide showed increased sensitivity to NO-mediated vasodilation, a significant decrease in fasting glycemia and insulinemia, and a significant decrease in systemic oxidative stress. In conclusion, our results suggest that gliclazide treatment improves NO-mediated vasodilation in diabetic GK rats with dyslipidemia probably due to its antioxidant effects, although we cannot rule out substantial benefits due to a reduction in fasting blood glucose. The availability of a compound that simultaneously decreases hyperglycemia, hyperinsulinemia, and inhibits oxidative stress is a promising therapeutic candidate for the prevention of vascular complications of diabetes.
- Apolipoprotein E epsilon-4 polymorphism is associated with younger age at referral to a lipidology clinic and a poorer response to lipid-lowering therapyPublication . Baptista, R; Rebelo, M; Decq-Mota, J; Dias, P; Monteiro, P; Providência, LA; Silva, JMThe risk of coronary heart disease (CHD) is related to environmental factors and genetic variants. Apolipoprotein E (apoE) polymorphisms are heritable determinants of total and low-density lipoprotein cholesterol, with some authors suggesting an association between the ε4 allele and CHD. We investigated the relationship between apoE genotype and age at referral to a specialized lipid clinic by the primary care physician and whether the benefits of treatment with statin differed between genotypes. METHODS: We assessed individual apoE genotypes and lipid blood profile in a total of 463 patients followed at a specialized lipid clinic due to dyslipidemia, with a 3-year median follow-up time. The primary care physician at the time of the referral had no access to the apoE genotyping results. Carriers of apoE ε4/ε2 genotype were excluded. RESULTS: The frequencies of ε2, ε3 and ε4 alleles were 7.8, 78.9 and 13.3%, respectively. There were no significant differences between genders. Although with similar lipid profiles and antidyslipidemic drug usage at baseline, ε4-carriers were referred to the clinic at a younger age (44.2 ± 14.7 years) compared with non-ε4 carriers (50.6 ± 13.8 years) (p < 0.001), with a substantially younger age of referral for homozygous E4/4 and for all genotypes with at least one copy of the ε4 allele (p < 0.001 for trend). Although both ε4 and non-ε4 carriers achieved significant reductions in total cholesterol during follow-up (p < 0.001 vs. baseline), the mean relative decrease in total cholesterol levels was higher in non-ε4 carriers (-19.9 ± 2.3%) compared with ε4 carriers (-11.8 ± 2.3%), p = 0.003. CONCLUSION: Our findings support the concept that there is a reduced response to anti-dyslipidemic treatment in ε4 carriers; this can be a contributing factor for the earlier referral of these patients to our specialized lipid clinic and reinforces the usefulness of apoE genotyping in predicting patients response to lipid lowering therapies.
- Artropatia Neuropática dos Ombros e SiringomieliaPublication . Garcia, J; Saavedra, MJ; Monteiro, P; Pereira da Silva, JA; Malcata, AB
- Can we improve outcomes in patients with previous coronary artery bypass surgery admitted for acute coronary syndrome?Publication . Teixeira, R; Lourenço, C; António, N; Jorge, E; Baptista, R; Saraiva, F; Mendes, P; Monteiro, S; Gonçalves, F; Monteiro, P; Freitas, M; Providência, LAINTRODUCTION AND OBJECTIVES: Prognosis and in-hospital management of patients with acute coronary syndrome (ACS) and a history of coronary artery bypass graft (CABG) surgery are still debated. The objective of this study was to characterize ACS patients with a CABG and to compare their in-hospital and postdischarge outcomes with those of patients without a CABG. METHODS: This ongoing prospective observational study included 1,495 consecutive patients admitted for ACS to a coronary care unit and followed up for a mean of 19 months. There were two groups: group A (n=73), with CABGs; and group B (n=1,223), without CABGs. RESULTS: Group A patients were more often male (86.3% versus 69.1%; P=.002), and more frequently had a history of diabetes, myocardial infarction and heart failure. Group B patients more frequently had ST-elevation myocardial infarction, and had a higher median ejection fraction (53% [interquartile range, 47%-60%] vs. 50% [42%-55%]; P< .01) and peak troponin-I concentration. There was no difference in the use of invasive techniques. Regarding medication, Group B patients were more likely to receive dual antiplatelet therapy at discharge. No significant difference was observed in in-hospital mortality (9.5% versus 5.9%; P=.2) or mortality at 1 month, 6 months or 1 year (9.8% versus 9.1%; log-rank test, P=.87) and the cumulative major adverse cardiac event rate was equally low in both groups. The presence of a CABG was associated with more readmissions for unstable angina (11.3% vs. 3.1%; P< .01). CONCLUSIONS: In our ACS patients, the presence of a CABG had no significant influence on short- or medium-term outcomes, such as all-cause mortality and adverse cardiac events.
- Carvedilol improves energy production during acute global myocardial ischaemiaPublication . Monteiro, P; Duarte, AI; Moreno, AJ; Gonçalves, L; Providência, LACardiac mitochondria may become dysfunctional during ischaemia, thus compromising cardiomyocyte function. Carvedilol is an alpha(1)/beta-adrenoceptor antagonist with antioxidant, neuroprotective, cardioprotective and vascularprotective properties, and is used to treat hypertension, myocardial ischaemia and congestive heart failure. However, its impact on mitochondrial function during acute prolonged ischaemia is unknown. We aimed to study the effect of carvedilol on cardiac mitochondrial function during acute ischaemia, using Wistar rat hearts perfused with a Langendorff system, and then submitted to ischaemia in the presence and absence of carvedilol. We determined the electrical potential of the mitochondrial membrane, O(2) consumption by the respiratory chain, energy charge and the activity of the mitochondrial respiratory chain complexes. In our model, carvedilol had a preferential action on phosphorylation, increasing the mitochondrial energy charge (0.76+/-0.03 vs. 0.65+/-0.01 arbitrary units; P<0.05) and decreasing the phosphorylation lag phase (28.64+/-4.23 vs. 62.4+/-11.63 s; P<0.05) during ischaemia. The larger amount of energy available allowed the preservation of the electrical potential (201.2+/-2.45 vs. 186.66+/-3.36 mV;P<0.05), thus improving mitochondrial function during acute prolonged ischaemia
- Carvedilol: Relação Entre A Actividade Antioxidante e Inibição da Transição de Permeabilidade MitocondrialPublication . Oliveira, PJ; Esteves, T; Rolo, AP; Monteiro, P; Gonçalves, L; Palmeira, CM; Moreno, AJOBJECTIVES: The mitochondrial permeability transition (MPT) is an event related to severe oxidative stress (for example, during myocardial ischemia and reperfusion) and excessive mitochondrial calcium accumulation, also being implicated in cell death. In this study, we compared the effect of carvedilol on the cardiac MPT induced by calcium and phosphate (Ca/Pi) and calcium/carboxyatractyloside (Ca/Catr). Oxidative stress plays a major role in MPT induction by Ca/Pi, leading to the oxidation of protein thiol groups, in contrast with Ca/Catr, where such oxidation is secondary to MPT induction and is not caused by oxidative stress. MATERIALS AND METHODS: Mitochondria were isolated from rat hearts and parameters related to MPT induction were evaluated (n = 5 for each inducer): mitochondrial swelling and oxidation of protein thiol groups (both measured by spectrophotometry). RESULTS: Using Ca/Pi, carvedilol protected mitochondria from MPT induction, particularly in its high conductance form. Its effect was demonstrated by analyzing the decrease in mitochondrial swelling amplitude. Simultaneously, we observed inhibition of protein thiol group oxidation (p < 0.001). By contrast, carvedilol did not show any protective effect with Ca/Catr. CONCLUSIONS: Carvedilol was only effective against the MPT when the oxidation of protein thiol groups was the cause and not the consequence of the MPT phenomenon. The results clearly show that during myocardial aggressions (ischemia and reperfusion, for example), the protective effect of carvedilol is primarily due to an antioxidant mechanism, inhibiting the production and effects of reactive oxygen species.
- Complexo de Carney a propósito de um caso clínicoPublication . Teixeira, R; Lourenço, C; Coelho, L; Vieira, H; Ramos, D; Castro, G; Monteiro, P; Donato, P; Ferreira, MJ; Providência, LA