Nutrição e Doença Cardiovascular. 1ª Parte

O autor descreve de forma resumida a classificação dos factores de risco cardiovascular e a sua influência na modulação dos estilos de vida ocidentalizados. Os padrões alimentares são também sumariamente referidos, bem como o seu papel na pandemia das doenças do conglomerado. Para terminar, as principais características alimentares e nutricionais da alimentação mediterrânea, como paradigma do padrão alimentar saudável, e o seu papel na prevenção das referidas doenças são também expostas.

Nutrição e Doença Cardiovascular. 2ª Parte

O autor descreve de forma mais detalhada a abordagem nutricional das dislipidemias e da hipertensão arterial. Quanto à primeira questão, aspectos como o papel dos ácidos gordos, a relação entre o colesterol alimentar e o colesterol plasmático, o papel dos vegetais, frutos e do amido e as indicações para a utilização de suplementos vitamínicos são referidos. Quanto à segunda, aspectos como a redução do excesso de peso e do sal, a utilização de suplementos de potássio, cálcio e magnésio, os macronutrientes, a cafeína, o álcool e o papel da actividade física são expostos.

Mesenchymal Stem Cell Therapy in Heart Disease

Cardiovascular disease is among the main causes of mortality and morbidity worldwide. Despite significant advances in medical and interventional therapy, the prognosis of conditions such as ischemic heart disease is still dismal. There is thus a need to investigate new therapeutic tools, one of which is stem cell therapy. Hematopoietic stem cells are the most studied type, and the fact that their biology is relatively well understood has led to their being used in preclinical research and clinical trials. However, the results of some of these studies have been controversial, which has opened the way for studies on other cell types, such as mesenchymal stem cells. These cells have immunomodulatory properties which suggest that they have therapeutic potential in cardiology. In the present article, the authors review the state of the art regarding mesenchymal stem cells, from basic and translational research to their use in clinical trials on ischemic heart disease, heart failure and arrhythmias, and discuss possible future uses.

Peripheral Artery Disease Patients May Benefit More from Aggressive Secondary Prevention than Aneurysm Patients to Improve Survival

BACKGROUND AND AIMS: Although it has become clear that aneurysmal and occlusive arterial disease represent two distinct etiologic entities, it is still unknown whether the two vascular pathologies are prognostically different. We aim to assess the long-term vital prognosis of patients with abdominal aortic aneurysmal disease (AAA) or peripheral artery disease (PAD), focusing on possible differences in survival, prognostic risk profiles and causes of death. METHODS: Patients undergoing elective surgery for isolated AAA or PAD between 2003 and 2011 were retrospectively included. Differences in postoperative survival were determined using Kaplan-Meier and Cox regression analysis. Prognostic risk profiles were also established with Cox regression analysis. RESULTS: 429 and 338 patients were included in the AAA and PAD groups, respectively. AAA patients were older (71.7 vs. 63.3 years, p < 0.001), yet overall survival following surgery did not differ (HR: 1.16, 95% CI: 0.87-1.54). Neither was type of vascular disease associated with postoperative cardiovascular nor cancer-related death. However, in comparison with age- and gender-matched general populations, cardiovascular mortality was higher in PAD than AAA patients (48.3% vs. 17.3%). Survival of AAA and PAD patients was negatively affected by age, history of cancer and renal insufficiency. Additional determinants in the PAD group were diabetes and ischemic heart disease. CONCLUSIONS: Long-term survival after surgery for PAD and AAA is similar. However, overall life expectancy is significantly worse among PAD patients. The contribution of cardiovascular disease towards mortality in PAD patients warrants more aggressive secondary prevention to reduce cardiovascular mortality and improve longevity.

Da Disfunção Endotelial à Oclusão Vascular Papel do Sistema Renina - Angiotensina

There is a body of evidence that supports the important role of the renin-angiotensin system (RAS) in atherosclerotic disease and in the cardiovascular disease continuum: from endothelial dysfunction to vascular occlusion. In the earlier stages of vascular disease, the RAS promotes functional changes, of which endothelial dysfunction is the best example. The deposition of atherogenic lipoproteins in the intima, their oxidative modification and the onset and amplification of the inflammatory response strengthens the atherogenic role of the RAS. Inflammatory cells are one of the main sources of angiotensin-converting enzyme (ACE) and angiotensin II (Ang II) in the vascular wall, in a process that leads to structural changes in the artery and progression of atherosclerotic disease. Ang II promotes the migration of vascular smooth muscle cells and their phenotypic differentiation in synthesis that accelerates vascular disease. By modulating the inflammatory response and, in general, all the elements of the plaque, Ang II plays a part in its instability, in the onset of acute events and in the promotion of the local prothrombotic state that leads to infarction.

Estudo Comparativo, Aleatorizado, em Dupla Ocultação, de Orlistat Versus Placebo, de Eficácia e Segurança, em Doentes Obesos com Hipercolesterolemia Ligeira a Moderada

INTRODUCTION: Obesity is a chronic disease and a serious health problem that leads to increased prevalence of diabetes, hypertension, dyslipidemia and gallbladder disease. OBJECTIVE: To evaluate the efficacy of orlistat for weight loss and improved lipid profile compared to placebo in obese patients with hypercholesterolemia, treated over a period of 6 months. METHODOLOGY: In a 6-month, multicenter (10 centers in Portugal), double-blind, parallel, placebo-controlled study, 166 patients, aged 18-65 years, body mass index (BMI) > or = 27 kg/m2, LDL cholesterol > 155 mg/dl, were randomized to a reduced calorie diet (600 kcal/day deficit) plus orlistat three times a day or placebo. Exclusion criteria included triglycerides > 400 mg/dl, severe cardiovascular disease, uncontrolled hypertension, type 1 or 2 diabetes under pharmacological treatment, and gastrointestinal or pancreatic disease. RESULTS: The mean difference in weight from baseline was 5.9% (5.6 kg) in the orlistat group vs. 2.3% (2.2 kg) in the placebo group. In the orlistat group 49% of patients achieved 5-10% weight loss and 8.8% achieved > 10%. The orlistat group showed a significant reduction in total and LDL cholesterol, with similar changes for HDL in both treatment groups. The frequency of gastrointestinal adverse events was slightly higher in the orlistat group than in the placebo group, leading to discontinuation in 7 patients. CONCLUSION: Treatment with orlistat plus a reduced calorie diet for 6 months achieved significant reductions in weight, BMI and lipid parameters.

Effect of Efavirenz on High-Density Lipoprotein Antioxidant Properties in HIV-Infected Patients

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: * In previous work, we showed a long-term and concentration-dependent beneficial effect of the non-nucleoside reverse transcriptase inhibitor efavirenz (EFV) on high-density lipoproteins (HDL) in human immunodeficiency virus (HIV)-infected patients. * Furthermore, it has been suggested that instead of the current practice of only measuring HDL-chelesterol values, the evaluation of HDL function, namely its antioxidant properties, might be an improved tool for identifying subjects at increased risk for cardiovascular events. * Paraoxonase-1 (PON-1) is an enzyme associated with HDL that is responsible for HDL antioxidant function. WHAT THIS STUDY ADDS: * In the present work, we studied the effect of EFV on the activity of PON-1 and showed, for the first time, that EFV-based antiretroviral therapy is associated with a better antioxidant function, i.e. with a higher PON-1 activity. AIMS: A long-term and concentration-dependent beneficial effect of efavirenz (EFV) on cholesterol associated with high-density lipoprotein (HDL-c) in human immunodeficiency virus (HIV)-infected patients has been documented. Furthermore, it has been suggested that, instead of the current practice of only measuring HDL-c values, the evaluation of HDL quality might be an improved tool for identifying subjects at increased risk of cardiovascular events. Paraoxonase-1 (PON-1) is an enzyme associated with HDL that is involved in the onset of cardiovascular disease and responsible for HDL antioxidant function. The aim of the present study was to investigate the effect of EFV on the circulating activity of PON-1 in HIV-infected patients. METHODS: The patients included were adults with a documented HIV-1 infection, nontreated or treated with antiretroviral regimens including EFV 600 mg once daily as first therapeutic regimen for at least 3 months. The influence of treatment with EFV, HDL-c and CD4 cell count on PON-1 activity was analysed. RESULTS: HIV-infected White patients treated with EFV had higher PON-1 activity [77.35 U l(-1) (65.66, 89.04)] (P < 0.05) and higher PON-1 activity : HDL-c ratio [1.88 (1.49, 2.28)] (P < 0.01) than untreated patients. PON-1 activity was higher in Black patients (P < 0.001) and in patients with a CD4 cell count >500 cells ml(-1) (P= 0.0120). CONCLUSIONS: EFV-based antiretroviral regimens are associated with HDL particles with a better antioxidant function, i.e. with a higher PON-1 activity. The PON-1 activity of Black patients is higher than that found in Whites regardless of treatment. Ethnicity should be taken into consideration when studying drug effects on PON-1 activity.

Invasive Assessment of the Coronary Microcirculation Using the Index of Microcirculatory Resistance: Description and Validation of an Animal Model

INTRODUCTION: The index of microcirculatory resistance (IMR) enables/provides quantitative, invasive, and real-time assessment of coronary microcirculation status. AIMS: The primary aim of this study was to validate the assessment of IMR in a large animal model, and the secondary aim was to compare two doses of intracoronary papaverine, 5 and 10 mg, for induction of maximal hyperemia and its evolution over time. METHODS: Measurements of IMR were performed in eight pigs. Mean distal pressure (Pd) and mean transit time (Tmn) were measured at rest and at maximal hyperemia induced with intracoronary papaverine, 5 and 10 mg, and after 2, 5, 8 and 10 minutes. Disruption of the microcirculation was achieved by selective injection of 40-μm microspheres via a microcatheter in the left anterior descending artery. RESULTS: In each animal 14 IMR measurements were made. There were no differences between the two doses of papaverine regarding Pd response and IMR values - 11 ± 4.5 U with 5 mg and 10.6 ± 3 U with 10 mg (p=0.612). The evolution of IMR over time was also similar with the two doses, with significant differences from resting values disappearing after five minutes of intracoronary papaverine administration. IMR increased with disrupted microcirculation in all animals (41 ± 16 U, p=0.001). CONCLUSIONS: IMR provides invasive and real-time assessment of coronary microcirculation. Disruption of the microvascular bed is associated with a significant increase in IMR. A 5-mg dose of intracoronary papaverine is as effective as a 10-mg dose in inducing maximal hyperemia. After five minutes of papaverine administration there is no significant difference from resting hemodynamic status.

Benefits of Selective Vitamin D Receptor Activators in Kidney Transplanted Patients

Severe chronic kidney disease may lead to disturbances, such as hyperphosphatemia, increased secretion of fibroblast growth factor -23 (FGF -23) and vitamin D deficiency. These may increase plasmatic levels of parathyroid hormone, and decrease plasmatic levels of calcium. Altogether, these may contribute to the development of secondary hyperparathyroidism, and to abnormalities in mineral metabolism. Kidney transplantation is the best option to improve longevity and quality of life in end -stage chronic kidney disease patients. Vitamin D deficiency has been associated with cardiovascular disease, which is the leading cause of death in chronic kidney disease. Therefore, diagnosing this deficiency may be pivotal for minimizing mortality in chronic kidney disease, because pharmacological treatments for this deficiency may be prescribed. Calcitriol is indicated for the treatment of vitamin D deficiency, both in chronic kidney disease and in kidney transplanted patients. However, calcitriol may increase the plasmatic levels of calcium and phosphorous, which can lead to vascular calcifications, that have been associated with cardiovascular mortality. Selective vitamin D receptor activators are indicated for the treatment of vitamin D deficiency in chronic kidney disease. These have the advantage of being associated with lower increases of plasmatic levels of calcium and phosphorous. These drugs also seem to have additional effects that may minimise patient morbidity and mortality, especially due to potentially reducing cardiovascular events. Unfortunately, there are few studies about the use of these drugs in kidney transplanted patients. Here we present a review about the physiology of vitamin D, the consequences of its deficiency in chronic kidney disease and in kidney transplanted patients, and about the diagnosis and treatment of this deficiency. Finally, we discuss the new line of research about the efficacy and safety of selective vitamin D receptor activators in kidney transplanted patients.