Thrombocytopenia after Aortic Valve Replacement with Perceval S Sutureless Bioprosthesis.

BACKGROUND AND AIM OF THE STUDY: Sutureless aortic bioprosthetic valves have become an alternative to conventional bioprostheses in high surgical risk cases. A significant decline in platelet count during the immediate postoperative period was observed in cases of Perceval S sutureless aortic valve implantation. The study aim was to determine how the reduction in platelet count after Perceval S prosthesis implantation compared to that after other bioprosthesis implants.

Left ventricular assist devices in patients with end-stage heart failure: suggestion of an alternative treatment based on clinically well-known concepts.

Encouraging results were obtained by using left ventricular assist devices (LVADs) in patients with end-stage heart failure (HF) that exhibits extremely high mortality and who were not candidates for heart transplantation. By using this so-called destination therapy (DT), a substantial percentage of these patients achieved sufficient improvement in cardiac function to permit the explantation of the device. The combination of mechanical and pharmacological therapy increased the frequency and durability of myocardial recovery as compared with other therapeutic approaches.

The role of intracellular 3'5'-cyclic adenosine monophosphate (cAMP) in atherosclerosis.

Intracellular cAMP is an ubiquitous intracellular second messenger that regulates important cellular functions. Intracellular cAMP levels are regulated by the enzymes adenylyl cyclase and phosphodiesterases. The role of cAMP in atherosclerosis is not widely accepted and incompletely characterized.

The role of the stress-related anti-inflammatory hormones ACTH and cortisol in atherosclerosis.

Chronic stress and probably the accompanying changes in personal behaviours can influence life expectancy. The role of adrenocorticotropic hormone (ACTH) and cortisol in atherosclerosis is not widely accepted and incompletely characterized. Several reports support a role of these hormones in atherogenesis by modulating the function of vascular endothelium, the recruitment of circulating monocytes to the artery wall and their differentiation into macrophages- foam cells, by controlling the expression of pro- and anti-inflammatory interleukins.

Acute arterial thrombosis in the absence of inflammation: the stress-related anti-inflammatory hormone ACTH participates in platelet-mediated thrombosis.

Objective: Despite the reciprocal relationship that exists between inflammation and thrombosis, we asked whether thrombosis can develop without inflammation, and whether stress-related hormones (ACTH and cortisol) influence platelet-mediated thrombosis.

Methods: We investigated the role of ACTH and cortisol in platelet aggregation, as well as on the circulating levels of IL-6 in pigs subjected to different treatments. In control animals, deep vessel wall injury (DVWI) was induced in the right common carotid artery, while in the animals under study DVWI was induced 60 min after ACTH administration (subgroup 1) or not at all (subgroup 2).

Effect of atherosclerosis on thermo-mechanical properties of arterial wall and its repercussion on plaque instability.

Data from the literature report febrile reactions prior to myocardial infarction in patients with normal coronary arteries and that coronary syndromes seem to be triggered by bacterial and viral infections, being fever the common symptom. The thermo-mechanical behavior of thoracic aortas of New Zealand White rabbits with different degrees of atherosclerosis was measured by means of pressure-diameter tests at different temperatures. Specific measurements of the thermal dilatation coefficient of atheroma plaques were performed by means of tensile tests.

Increases of corporal temperature as a risk factor of atherosclerotic plaque instability.

Background: This work explores for the first time the effects of temperature increments on the development of high shear stresses between plaque and arterial wall due to their different dilatational properties. Data from the literature report febrile reactions prior to myocardial infarction in patients with normal coronary arteries and that coronary syndromes seem to be triggered by bacterial and viral infections, being fever the common symptom.

Methods: The thermo-mechanical behavior of thoracic aortas of New Zealand White rabbits with different degrees of atherosclerosis was measured by means of pressure-diameter tests at different temperatures.

Pathological effects of pulmonary vein beta-radiation in a swine model.

Introduction: Atrial fibrillation (AF) may be triggered by ectopic beats originating in sleeves of atrial myocardium entering the pulmonary veins (PVs). PV isolation by means of circumferential ostial or atrial radiofrequency ablation is an effective but also a difficult and long procedure, requiring extensive applications that can have serious potential complications. Our objective was to examine pathological effects of PV beta-radiation, particularly the ability to destroy PV myocardial sleeves without inducing PV stenosis and other unwanted effects, in order to establish its potential feasibility for the treatment of AF.

Atherogenesis takes place in cholesterol-fed rabbits when circulating concentrations of endogenous cortisol are increased and inflammation suppressed.

Atherosclerosis is an inflammatory disease, but the response of the endogenous anti-inflammatory system during this process has not been evaluated previously. Cortisol is the end product of this anti-inflammatory system, but is also able to activate cellular processes that induce atherogenesis; however, it is unknown whether atherogenesis occurs when circulating concentrations of endogenous cortisol are increased or when they are decreased. We have evaluated the counter-regulatory responses of cortisol and interleukin-1beta (IL-1beta) during the short- and long-term responses to vascular injury in rabbits fed a 2% cholesterol diet.

Intracoronary brachytherapy after stenting de novo lesions in diabetic patients: results of a randomized intravascular ultrasound study.

Objectives: We studied the efficacy of intracoronary brachytherapy (ICB) after successful coronary stenting in diabetic patients with de novo lesions.

Background: Intracoronary brachytherapy has proven effective in preventing recurrences in patients with in-stent restenosis. However, the role of ICB for the treatment of de novo coronary stenoses remains controversial.

Effects of bosentan on neointimal response following coronary angioplasty.

Background: Endothelins are important vasoconstrictors and cellular-growth promoters. ETA-specific antagonists have been shown to reduce neointimal response to injury in some experimental angioplasty models. However, there is little information on the effects of dual ETA/ETB receptor blockers, such as bosentan, on neointimal proliferation following experimental coronary angioplasty.

Morning cortisol production in coronary heart disease patients.

Background: The circadian cycle of the endogenous anti-inflammatory system (EAIS) is characterized by a morning increase in cortisol production. Circulating interleukin-6 (IL-6) activates the EAIS. A circadian variation in the onset of myocardial infarction, sudden death, stable angina (SA) and unstable angina (UA) has been reported.

Endogenous anti-inflammatory response after coronary injury in a porcine model.

Background: Corticotropin-releasing hormone (CRH)/adrenocorticotropic hormone (ACTH)/cortisol is the major anti-inflammatory system. After percutaneous translumenal angioplasty, an inflammatory process is triggered. We investigate whether CRH/ACTH/cortisol axis is activated after deep vessel wall injury (DVWI).

[Effect of cAMP on the function of endothelial cells and fibromuscular proliferation after the injury of the carotid and coronary arteries in a porcine model].

Introduction And Objective: Reendothelization of damaged blood vessels protects against the vascular injury response. We evaluated in vivo whether a systemic increase in cAMP accelerates reendothelization and attenuates intimal hyperplasia in injured swine carotid and coronary arteries.

Methods: Both carotid arteries of 10 swines were subjected to balloon injury.

Does focal destruction of the thoracic aorta wall by Staphylococcus aureus lead to the development of infected aneurysms? An experimental study.

Objective: The infrequency of infected aneurysms suggests that either infection of segments of the aortic wall is uncommon, or that infections do not always lead top infected aneurysm formation. The purpose of the study was to determine whether focal Staphylococcus aureus infection of aortic wall segments leads consistently to the development of infected aneurysms and to evaluate the segments in which infection did not lead to the infected aneurysm formation.

Methods: Twenty pigs were inoculated with 0.

Effect of magnesium sulfate administration on subendocardial and subepicardial perfusion.

The objective of this study was to determine the effect of systemic MgSO4 infusion on subendocardial and subepicardial perfusion. Seventeen spontaneously breathing piglets were examined. Myocardial perfusion was measured using radiolabeled microspheres at baseline, 30 and 60 min after either MgSO4 (80 mg/kg) or saline infusion.

A new experimental model of isolated myocardial ischemic injury: ECG findings of acute isolated right ventricular ischemic injury.

A new experimental porcine model for creating selective ischemia of a specific part of the myocardium while the rest of the myocardium remains free of ischemia has been used to study the electrocardiographic (ECG) changes deriving from selective ischemia of the right ventricular (RV) free wall. A patch was stitched to the ventricle to produce selective myocardial ischemic injury. In a preliminary study of nine pigs, selective ischemia of the left ventricular free wall in five and of the RV free wall in four animals was induced, and a postmortem dye injection was performed to evaluate blood flow in the area of ischemia.

Ethanol intake, plasma catecholamine levels, and ST-segment changes without myocardial injury in rats with short-term ethanol consumption.

The authors studied the effect of short-term ethanol consumption on the ST-segment and the association between ST-segment changes and the amount of daily ethanol intake and levels of plasma catecholamines. The study used 63 rats (control group n = 20, study group n = 43). The rats in the study group were exposed for 6 days to progressively larger doses of ethanol followed by 15 days of continuous exposure to ethanol.

Intracellular (polymorphonuclear) magnesium content in patients with bronchial asthma between attacks.

Previous studies have demonstrated the role of polymorphonuclears in asthma, the importance of increases in intracellular concentrations of ionized calcium in the release of chemical mediators, the role of magnesium as natural calcium channel blocker, and the importance of magnesium deficiency in plasma histamine concentration and in tissue prostanoid concentration. The objective of our study was to measure the polymorphonuclear magnesium content in patients with asthma in the interval between attacks. We measured the polymorphonuclear magnesium content, and serum and erythrocyte sodium, calcium, and magnesium concentrations in 21 healthy volunteers and 50 patients with different types of asthma.

Direct atrioventricular versus atriopulmonary connection: a comparative experimental study.

A study of 31 dogs, divided into two groups, was conducted to compare direct atrioventricular with atriopulmonary connection using a valved conduit to treat tricuspid atresia. The first group (n = 9) acted as controls. In the second group (n = 22), an experimental model was established for direct atrioventricular connection that could be converted to atriopulmonary connection.