Antiplatelet combinations for prevention of atherothrombotic events

Antiplatelet therapy plays a fundamental role in reducing atherothrombotic events by several pathways. The present work reviews available evidence on antiplatelet therapy both for primary prevention and in the presence of established peripheral, cerebral, or cardiac ischemic disease. Due to the importance of adherence to therapy to achieve optimal effects, special attention is given to the use of fixed-dose oral formulations in the clinical subset of patients in whom double antiplatelet therapy has proven indications.

Chlamydia pneumoniae infection and cardiac risk factors in patients with myocardial infection

BACKGROUND

Evidences support the possible involvement of microorganisms such as Chlamydia pneumonia in the pathogenesis of ischemic heart diseases through a chronic inflammatory process. The aim of this study was to determine the relation between Chlamydia pneumoniae seropositivity with acute myocardial infarction and its related risk factors.

METHODS

In this case-control study, 88 patients admitted in CCU with a diagnosis of acute coronary syndrome, without a history of chronic diseases including cancers were selected as cases and 49 surgical patients without an evidence of cardiovascular disease according to clinical examinations and ECG were selected as controls. Demographic characteristics and background risk factors were obtained using a questionnaire by expert nurses. Venous blood sample was obtained from participants for measuring the anti Chlamydia IgG and IgM antibodies using ELISA method. The prevalence of antibodies was compared in both groups and its relation with coronary syndrome was evaluated.

RESULTS

88 and 49 patients were enrolled in case and control groups, respectively. Mean age of patients and the controls was 14±59.7 and 13±56.9 years, respectively (P=0.26). Anti Chlamydia IgG seropositivity rate was 63(71.9%) and 23(46.9%) in case and controlcontrol groups, respectively (P<0.01; OR: 2.85; CI 95%: 1.38-5.9). Anti Chlamydia IgM was positive in 1 patient and 1 control. Anti Chlamydia IgG seropositivity rate was higher in patients older than 50 years old than those younger than 50 years old (OR: 2.83; CI 95%: 1.31 -1.14). There was a significant relation between BMI, smoking and Anti Chlamydia IgG seropositivity.

CONCLUSION

Considering the relation between anti Chlamydia antibody IgG seropositivity with BMI and myocardial infarction, it seems that appropriate diagnosis and treatment of these prone patients can be benefical.

Acute myocardial infarction caused by coronary artery dissection after a blunt chest trauma

Acute myocardial infarction is a life-threatening condition. Coronary dissection after blunt chest trauma is a rare event. Chest pain is a common symptom after chest trauma, which may relate to chest contusion without cardiac injury or myocardial infarction. Differentiation between minor cardiac contusion and significant cardiac injury is difficult and it is a challenge for physicians to diagnose traumatic cardiac injury early. We report a case of a 40-year-old man suffering from coronary artery dissection after a blunt chest trauma and intracranial hemorrhage after percutaneous coronary intervention.

Ergonovine stress echocardiography: Recent experience and safety in our centre

AIM

To study recent experience and safety of ergonovine stress echocardiography in our centre.

METHODS

In this study we collected the clinical variables of patients referred since 2002 for ergonovine stress echocardiography, in addition to indications, the results of this test, complications, blood pressure and heart rate values during the test and the number and results of tests requested before this technique.

RESULTS

We performed 40 tests in 38 patients, 2 tests were carried out to verify therapy efficacy. The prevalence of classic cardiovascular risk factors was low and the most frequent indication was chest pain (57.5%). Coronary angiography was performed in 32 patients, and showed normal coronary arteries in 27 patients and non-significant stenosis in 5 cases. In 16 patients, coronary angiography was carried out after a positive or inconclusive ischemia test. Another 6 patients had a normal stress test (5 exercise electrocardiography tests and 1 nuclear imaging test). Of the 40 ergonovine stress echocardiography tests, 6 were positive (4 in the right coronary artery territory and 2 in the circumflex coronary artery territory), all of them by echocardiographic criteria, and by electrocardiographic criteria in only 3 (50%). The presence of non-significant coronary artery stenosis was more frequent in patients with positive ergonovine stress echocardiography (50% vs 6%, P = 0.038), and were related to ischemic territory. During the maximum stress stage, there was a higher systolic (130.26 ± 19.17 mmHg vs 136.58 ± 27.27 mmHg, 95% CI: -12.77 to 0.14 mmHg, P = 0.055) and diastolic blood pressure (77.89 ± 13.49 mmHg vs 83.95 ± 15.73 mmHg, 95% CI: -10.41 to -1.69 mmHg, P = 0.008) than at the baseline stage, and the same was registered with heart rate (73 ± 10.96 beats/min vs 79.79 ± 11.72 beats/min, 95% CI: -9.46 to -4.11 beats/min, P < 0.01). Nevertheless, there were only 2 hypertensive reactions during the last stage, which did not force a premature end to the test, without sustained tachy or bradyarrhythmias, and the technique was well tolerated in 58% of cases. A unique complication (2.5%) of this test was a prolonged vasospasm with a slight increase in necrosis biomarkers, however, this was without repercussion.

CONCLUSION

Ergonovine stress echocardiography can be performed with safety, is well tolerated in the majority of cases, and is useful for determining the ischemia mechanism in selected cases.

Inflammation and reactive oxygen species in cardiovascular disease

Reactive oxygen species (ROS) have long been proposed to be mediators of experimental cardiovascular pathology. There is also a wealth of data indicating that ROS are involved in clinical cardiovascular pathology. However, multiple clinical studies have shown little benefit from anti-oxidant treatments, whereas nearly all experimental studies have shown a marked effect of anti-oxidant therapy. One reason for this discrepancy is that ROS are produced through multiple different mechanisms of which some are clinically beneficial; thus, in a defined experimental system where predominately pathological ROS are generated does not mimic a clinical setting where there are likely to be multiple ROS generating systems producing beneficial and pathological ROS. Simple inhibition of ROS would not be expected to have the same result in these two situations; ergo, it is important to understand the molecular mechanism underlying the production of ROS so that clinical treatments can be tailored to target the pathological production of ROS. One such example of this in cardiovascular biology is tissue specific inflammation-mediated ROS generation. This and the following series of articles discuss the current understanding of the role of ROS in cardiovascular disease, specifically focusing on the molecular mechanisms of ROS generation and the actions of ROS within the cardiovascular system. Although there are still many areas with regard to the effects of ROS in the cardiovascular system that are not completely understood, there is a wealth of data suggesting that blocking pathological ROS production is likely to have beneficial clinical effects compared to traditional anti-oxidants.

Heart failure and chronic obstructive pulmonary disease: Two for tea or tea for two?

A combination of chronic obstructive pulmonary disease (COPD) and heart failure (HF) is common yet it is inadequately and rarely recognized. Because of the similar clinical manifestations, comorbidity is frequently not considered and appropriate diagnostic tests are not performed. It is very important that a combination of COPD and HF is recognized as these patients have a worse prognosis than patients with an individual disease. When present, COPD should not prevent the use of life-saving therapy in patients with HF, particularly β-blockers. Despite clear evidence of the safety and tolerability of cardioselective β-blockers in COPD patients, these drugs remain grossly underprescribed and underdosed. Routine spirometry and echocardiography in HF and COPD patients, respectively, is therefore warranted to improve current clinical practice.

Evaluation of Greek high school teachers' knowledge in basic life support, automated external defibrillation, and foreign body airway obstruction: implications for nursing interventions

INTRODUCTION

The aim of this study was to evaluate the theoretic knowledge of high school teachers regarding cardiopulmonary resuscitation, automated external defibrillation, and foreign body airway obstruction.

METHODS

Three hundred ten respondents were tested prospectively by use of a scoring system. Data were obtained by use of a questionnaire that included 24 questions. Data were collected between April 9 and June 16, 2009.

RESULTS

Only 21.03% of the teachers had ever participated in life support courses, and most of them did not possess adequate theoretic knowledge in the management of adult cardiac arrest or foreign body airway obstruction. As the age of the teachers increases, the ratio of correct answers decreases. Life support course attendance has a positive effect on their theoretic knowledge. The majority of the teachers would welcome an emergency nurse to educate them and their students on basic life support and foreign body airway obstruction.

DISCUSSION

This study shows that most of the respondents had a mediocre level of knowledge in basic life support, automated external defibrillation, and foreign body airway obstruction. Given that emergency nurses regularly practice resuscitation in the emergency department in which they are working, they have the motivation to be kept updated with the current guidelines on resuscitation, because guidelines on resuscitation are revised every 5 years. Teachers, on the other hand, are less motivated to be kept updated; thus emergency nurses may be the key component in educating teachers and school students. Therefore we believe that emergency nurses should take on the responsibility and act as school educators regarding cardiopulmonary resuscitation.

Role of cardiovascular imaging in systemic autoimmune diseases

Systemic autoimmune diseases are characterized by an excess of cardiovascular (CV) morbidity and mortality compared to the general population, mainly due to chronic inflammation that promotes the development of endothelial dysfunction and enhanced atherosclerosis. Early diagnosis of silent CV involvement is mandatory to improve the long term prognosis of these patients and CV imaging provides valuable information as a reliable diagnostic tool. Transthoracic echocardiography, with several applications (e.g. coronary flow reserve evaluation, tissue Doppler imaging, speckle tracking and the transesophageal approach), represents a first line evaluation, in association with biomarkers of endothelial dysfunction, such as asymmetric dimethylarginine. Nuclear medicine provides useful information on myocardial perfusion. The aim of this editorial is to provide a brief but complete review of the diagnostic tools available for screening and follow up of CV involvement in systemic autoimmune diseases.

Myocardial ischemia-reperfusion injury: Possible role of melatonin

Our knowledge and understanding of the pathophysiology of coronary atherosclerosis has increased enormously over the last 20 years. Reperfusion through thrombolysis or percutaneous coronary angioplasty is the standard treatment for preventing acute myocardial infarction. Early reperfusion is an absolute prerequisite for survival of the ischemic myocardium, but reperfusion itself may lead to accelerated and additional myocardial injury beyond that generated by ischemia alone. These outcomes, in a range of reperfusion-associated pathologies, are collectively termed "reperfusion injuries". Reactive oxygen species are known to be produced in large quantities in the first few minutes of the post-ischemia reperfusion process. Similarly, scientific evidence from the last 15 years has suggested that melatonin has beneficial effects on the cardiovascular system. The presence of vascular melatoninergic receptor binding sites has been demonstrated; these receptors are functionally linked to vasoconstrictor or vasodilatory effects of melatonin. It has been shown that patients with coronary heart disease have a low melatonin production rate, especially those with higher risk of cardiac infarction and/or sudden death. Melatonin attenuates molecular and cellular damage resulting from cardiac ischemia-reperfusion in which destructive free radicals are involved.

The potential role of endogenous bacteriophages in controlling invading pathogens

Bacteriophages (phages) are omnipresent in our environment, and recent studies highlight their potential impact on the microbial world. Phages can also be present in mammalian organisms, including man (intestines, oral cavity, urine, sputum and serum). Data are available which suggest that those endogenous phages could play an important role in eliminating bacteria and regulating the body ecosystem. Furthermore, our most recent findings suggest that phages can exert immunosuppressive action in the gut, helping control local inflammatory and autoimmune reactions, and demonstrate anticancer activity. We hypothesize that phages could act in concert with the immune system in immunosurveillance against bacteria, viruses and cancer.

The ultimate nanoscale mincer: assembly, structure and active sites of the 20S proteasome core

20S proteasomes constitute the proteolytic core of large protease complexes found in all branches of life. Among these, the eukaryotic 26S proteasome ubiquitously poses as a vital final entity in regulated degradation of intracellular proteins. The composition of 20S core particles has been disclosed in detail, facilitated by groundbreaking studies on ancestral prokaryotic 20S proteasomes of low complexity and culminated in the crystal structure determination of the much more complex eukaryotic particles. This article first summarizes insights into the structural organization of the 20S core followed by characterization of its proteolytic activities, which are confined to the central cavity of the particle. In eukaryotes they reside in three different subunit types differing in their preference for cleavage sites in substrates as well as in their importance for the proteasome's cellular function. The second part reviews current knowledge on the biogenesis pathways of 20S core particles, which have to ensure not only the fixed subunit arrangement but also activation of proteolytic subunits in a late assembly state.

The oxygen affinity of haemoglobin Tak, a variant with an elongated beta chain

The oxygen affinity was investigated of purified Hb Tak, a human haemoglobin variant with elongated beta-chains. A very low P50 value was found which was not influenced by the addition of 2,3 diphosphoglycerate. The n value was 1, indicating non-cooperativity. The oxygen equilibrium curve of the whole blood haemolysate containing Hbs A and Tak was close to that of Hb A at the top of the curve, while the bottom of the curve greatly deviated from the latter, indicative of small if any interaction between Hb A and Tak during oxygenation.