Myocardial infarction with normal coronary arteries: a case report and review of the literature

<p>Abstract</p> <p>Introduction</p> <p>Although acute myocardial infarction is generally associated with obstructive coronary artery disease, myocardial infarction associated with normal coronary arteries is a well-known condition. The overall prevalence rate of myocardial infarction with normal coronary arteries is considered to be low, varying from 1% to12% depending on the definition of "normal" coronary arteries.</p> <p>Case presentation</p> <p>We describe here a case of a 49-year-old woman with a history of prior myocardial infarction who continued to be asymptomatic after a 10-year follow-up, in the absence of a high-risk profile for adverse outcomes. She was studied with multi-slice coronary computed tomography and whole-body angiography, which showed normal coronary and extra-coronary arteries.</p> <p>Conclusion</p> <p>This case report raises two important issues. First, the possible role of multi-slice computed tomography/coronary angiography in the risk- and prognosis assessment of patients with known or suspected coronary artery disease. Second, the important role played by long-term pharmacological therapy in patients with prior myocardial infarction and normal coronary arteries.</p

Antioxidants and atherosclerosis

A large body of evidence supports the hypothesis that oxidation of low-density lipoprotein plays a key role in atherogenesis. Experimental atherosclerosis in animals can be prevented by natural and synthetic antioxidants. Clinical trials with antioxidants, which mainly used vitamin E, showed contrasting findings. Thus. among five secondary prevention trials with vitamin E, three were negative and two were positive. Several factors have been suggested to explain these conflicting results, including compliance, trial design, the dosage used and the source of vitamin E. Thus. the results of clinical trials leave open the issue of antioxidant treatment in human atherosclerosis. (C) 2002 The European Society of Cardiology

Antioxidant strategy for cardiovascular disease

.Sir—In the Primary Prevention Project trial (Jan 13, p 89),1 the investigators assessed the effect of an antioxidant strategy in a population with at least one risk factor for cardiovascular disease. Patients received 300 mg synthetic vitamin E daily and were followed up for 4 years. No effect on cardiovascular events was noted

Fluorescence quenching of dipyridamole associated to peroxyl radical scavenging: a versatile probe to measure the chain breaking antioxidant activity of biomolecules

Dypiridamole is a highly efficient chain breaking antioxidant (Iuliano et al., Free Radic. Biol. Med. 18 (1995) 239-247) with an aromatic ring system responsible for an intense absorption band in the 400-480-nm region and for an intense fluorescence. Dipyridamole fluorescence is quantitatively quenched upon reaction with peroxyl radicals. In the presence of a flux of peroxyl radicals generated by thermal dissociation of ate-initiators, dipyridamole fluorescence decays linearly, showing a first-order reaction with respect to peroxyl radicals, and zero-order with respect to dipyridamole. The pH optimum for the fluorescence quenching is in the 7-8 range, from pH 7 to 6, the decay of fluorescence rapidly decreases to became negligible below pH 5.5. Dipyridamole consumption is blocked in the presence of an added chain breaking antioxidant for a time that is proportional to the antioxidant concentration. This effect is shown for ascorbic acid, trolox, vitamin E, uric acid, and N,N'-diphenyl-p-phenylenediamine. The slope of the linear correlation relative to trolox allows calculation of the bimolecular rate constant for a given molecule and peroxyl radicals. Comparison of data obtained by the dipyridamole consumption are comparable to values obtained by the oxygen consumption method. (C) 2000 Elsevier Science B.V. All rights reserved.Dypiridamole is a highly efficient chain breaking antioxidant (Iuliano et al., Free Radic. Biol. Med. 18 (1995) 239^247) with an aromatic ring system responsible for an intense absorption band in the 400^480-nm region and for an intense fluorescence. Dipyridamole fluorescence is quantitatively quenched upon reaction with peroxyl radicals. In the presence of a flux of peroxyl radicals generated by thermal dissociation of azo-initiators, dipyridamole fluorescence decays linearly, showing a first-order reaction with respect to peroxyl radicals, and zero-order with respect to dipyridamole. The pH optimum for the fluorescence quenching is in the 7^8 range, from pH 7 to 6, the decay of fluorescence rapidly decreases to became negligible below pH 5.5. Dipyridamole consumption is blocked in the presence of an added chain breaking antioxidant for a time that is proportional to the antioxidant concentration. This effect is shown for ascorbic acid, trolox, vitamin E, uric acid, and N,NP -diphenyl-p-phenylenediamine. The slope of the linear correlation relative to trolox allows calculation of the bimolecular rate constant for a given molecule and peroxyl radicals. Comparison of data obtained by the dipyridamole consumption are comparable to values obtained by the oxygen consumption method

Proactive Risk Assessment through Failure Mode and Effect Analysis (FMEA) for Perioperative Management Model of Oral Anticoagulant Therapy: A Pilot Project

Introduction: Correct perioperative management of anticoagulant therapy is essential to prevent thromboembolic events and reduce the risk of bleeding. The lack of universally accepted guidelines makes perioperative anticoagulant therapy management difficult. The present study aims to identify the perioperative risks of oral anticoagulant therapy and to reduce adverse events through Failure Mode and Effect Analysis (FMEA). Materials and Methods: A multidisciplinary working group was set up, and four main phases of the process were identified. Each of these phases was divided into micro-activities to identify the related possible failure modes and their potential consequences. The Risk Priority Number was calculated for each failure mode. Results and Discussion: Seventeen failure modes were identified in the entire perioperative period; those with a higher priority of intervention concern the incorrect timing between therapy suspension and surgery, and the incorrect assessment of the bleeding risk related to the invasive procedure. Conclusion: The FMEA method can help identify anticoagulant therapy perioperative failures and implement the management and patient safety of surgical procedures

Measurement of oxysterols and alpha-tocopherol in plasma and tissue samples as indices of oxidant stress status

Oxidant stress seems to play a role in several setting of human pathology, such as atherosclerosis, cancer, and aging. The study of oxidant stress in human disease should be based on the evaluation of either sensitive and specific markers of enhanced oxidant stress, such as oxysterols, or antioxidant defense, by measuring alpha-tocopherol. We have developed a rapid method to measure the oxysterols 7beta-hydroxycholesterol and 7-ketocholesterol in plasma (50 healthy subjects) and tissue as an index of oxidant stress in vivo, and from the same sample alpha-tocopherol content. The mean plasma concentration of 7beta-hydroxycholesterol and 7-ketocholesterol was 4.6 +/- 1.1 and 13.4 +/- 7.6 ng/mL, respectively. Plasma alpha-tocopherol concentration was 5.8 +/- 1.0 mumol/mol cholesterol. Samples from atherosclerotic plaques contained 20 times more cholesterol, about 45 times higher oxysterols levels, and 600 times more alpha-tocopherol compared to normal arteries. No significant difference in cholesterol and oxysterol content was observed between cirrhotic and normal liver. However, cirrhotic liver contained significantly smaller concentration of alpha-tocopherol compared to normal liver. In conclusion, we have developed a rapid and reliable method for the assay of cholesterol oxidation products and alpha-tocopherol in plasma and tissue useful for estimation of oxidant stress/antioxidant balance. (C) 2003 Elsevier Science (USA). All rights reserved

Proactive Risk Assessment Through Failure Mode and Effect Analysis (FMEA) for Haemodialysis Facilities: A Pilot Project

Haemodialysis (HD) is one of the methods for renal replacement therapy in the management of advanced chronic kidney disease through an osmosis process that allows purification of blood in the dialysis machine. The complexity of the dialytic procedure often requires the presence of a multi-specialist, multi-disciplinary team. The dialysis process is an important target for clinical risk management. Failure Mode and Effect Analysis (FMEA) is a proactive technique, considered a purposeful and dynamic tool for clinical risk management. FMEA is noted in five phases that allow a preliminary assessment of a definite process through identification and classification of risk priorities. This study represents the first of a two-phase project where FMEA is applied to HD in the setting of San Feliciano Hospital. The dialysis center performs ~12,000 dialysis sessions per year. The dialysis process is divided into different stages. A total of 31 failure modes were identified in the whole dialysis stages; more than 2/3 of the failure modes were related to the only connecting of the patient to the dialysis machine. The first phase of the study clearly remarked that the most critical step of the dialytic process is represented by the connection between the patient and the machine, as expected. Indeed, in order to have the dialysis set up, an arteriovenous fistula must be surgically created prior to the procedure and it is one of the most important issues in the HD process because of the necessity of a constant revision of it. FMEA application to HD is a useful tool, easy to be implemented and it is likely to nimbly reveal the practical and potential solutions to the critical steps of the procedure

Increased plasma levels of oxysterols, in vivo markers of oxidative stress, in patients with familial combined hyperlipidemia: Reduction during atorvastatin and fenofibrate therapy

Familial combined hyperlipidemia (FCHL), the most common inherited disorder of lipid metabolism, is associated with an increased risk of atherosclerosis that is not fully explained by the metabolic disturbances of these patients. Oxidative damage to lipid components accumulating in the plasma of FCHL patients might contribute to explaining this lack of evidence. Cholesterol is one of the preferential targets of oxidation in LDL and this may contribute to setting a proatherogenetic phenotype in FCHL. We investigated plasma oxysterols (7-ketocholesterol and 7 beta-hydroxycholesterol) and alpha-tocopherol as in vivo hallmarks of lipid-related oxidative stress. Oxidative stress hallmarks were measured in 45 FCHL patients and 54 sex- and age-matched healthy controls; in FCHL patients, oxidative stress and lipid profile parameters were also assessed in response to lipid-lowering drugs in a 24-week randomized, open-label trial with atorvastatin or fenofibrate. FCHL patients showed markedly increased levels of oxysterols (p < 0.001) and reduced alpha-tocopherol/total lipids (p < 0.001) compared to controls. These differences were independent of the presence of clinical atherosclerosis and persisted after correction for hyperlipidemia. Atorvastatin and fenofibrate significantly improved the lipid profile and caused a comparable decrease in plasma oxysterols, with the normalization of 7-ketocholesterol and a significant reduction of 7 beta-hydroxycholesterol (p < 0.001). These drugs also decreased the ratio of alpha-tocopherol/total lipids by more than 30% (p < 0.001). In conclusion, FCHL patients showed increased hallmarks of cholesterol oxidation and decreased levels of alpha-tocopherol/total lipids. Atorvastatin and fenofibrate displayed comparable efficiency in decreasing oxysterols, but they further decreased lipid-corrected alpha-tocopherol levels in plasma. More research work is needed to understand the clinical meaning of these findings, which may help to understand the role of oxidative stress in FCHL and lipid-lowering therapy. (c) 2006 Elsevier Inc. All rights reserved