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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Vasospasm can have many different causes and can occur in a variety of diseases, including infectious, autoimmune, and ophthalmic diseases, as well as in otherwise healthy subjects. We distinguish between the primary vasospastic syndrome and secondary vasospasm. The term "vasospastic syndrome" summarizes the symptoms of patients having such a diathesis as responding with spasm to stimuli like cold or emotional stress. Secondary vasospasm can occur in a number of autoimmune diseases, such as multiple sclerosis, lupus erythematosus, antiphospholipid syndrome, rheumatoid polyarthritis, giant cell arteritis, Behcet's disease, Buerger's disease and preeclampsia, and also in infectious diseases such as AIDS. Other potential causes for vasospasm are hemorrhages, homocysteinemia, head injury, acute intermittent porphyria, sickle cell disease, anorexia nervosa, Susac syndrome, mitochondriopathies, tumors, colitis ulcerosa, Crohn's disease, arteriosclerosis and drugs. Patients with primary vasospastic syndrome tend to suffer from cold hands, low blood pressure, and even migraine and silent myocardial ischemia. Valuable diagnostic tools for vasospastic diathesis are nailfold capillary microscopy and angiography, but probably the best indicator is an increased plasma level of endothelin-1. The eye is frequently involved in the vasospastic syndrome, and ocular manifestations of vasospasm include alteration of conjunctival vessels, corneal edema, retinal arterial and venous occlusions, choroidal ischemia, amaurosis fugax, AION, and glaucoma. Since the clinical impact of vascular dysregulation has only really been appreciated in the last few years, there has been little research in the according therapeutic field. The role of calcium channel blockers, magnesium, endothelin and glutamate antagonists, and gene therapy are discussed.
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PMID:Vasospasm, its role in the pathogenesis of diseases with particular reference to the eye. 1128 96

The etiology of a novel cardiac syndrome 'tako-tsubo' cardiomyopathy, otherwise known as 'transient left ventricular (LV) apical ballooning' and which mimics acute myocardial infarction, is not clear; however, emotional or physical stress is known to precede the attack. Left ventriculography of rats experiencing emotional stress induced reversible LV apical ballooning, which was normalized by pretreatment with adrenoceptor blockade. Together with results of previous studies, activation of cardiac adrenoceptors in the absence of ischemia-reperfusion is proposed as the primary cause of this syndrome.
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PMID:Emotional stress induces transient left ventricular hypocontraction in the rat via activation of cardiac adrenoceptors: a possible animal model of 'tako-tsubo' cardiomyopathy. 1238 Oct 99

As well as pheochromocytoma, in which it has been established that an excess of circulating catecholamines is responsible for the development of catecholamine-induced acute myopathy, some rare cases have been reported of a similar cardiac incident following intense emotional stress. In this study, the case has been examined of a 56-year old female with no history of cardiovascular disorder who presented with intense, nitro-resistant prolonged chest pain mimicking an acute coronary syndrome immediately following a situation involving major psychological stress. The admission electrocardiogram revealed a sharp decrease in R-wave amplitude in the right chest leads associated with an extended QT interval, and secondarily with subepicardiac ischemia in the lower leads. However, a few days after admission the electrical signs and septo-apical akinesia that had initially been observed by echocardiography completely disappeared. The clinical examination ruled out a diagnosis of myocardial necrosis, acute myocarditis, or pheochromocytoma. Moreover, no direct evidence of coronary spasm was found. The outcome was positive, with complete reversibility of all clinical signs and no organic sequelae. It is considered that this was probably a case of catecholaminergic acute cardiomyopathy triggered by intense emotional stress, a rare occurrence that should nevertheless be systematically taken into account in cases with similar clinical signs.
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PMID:[Myocardial pseudo-infarction: "stress"-associated catecholamine-induced acute cardiomyopathy or coronary spasm?]. 1255 32

We report on three patients with acute myocardial ischemia syndrome, without significant coronary artery disease, who were admitted within one year in our hospital and presenting an atypical balloon-like, reversible left ventricular apical wall motion abnormality. The reported cases showed the following similarities: 1) elderly women (age >65 years), 2) triggered by physical or emotional stress, 3) dynamic reversible ST-T segment abnormalities and 4) positive troponin I. During a one year follow-up, all patients remained asymptomatic. As compared to the usual forms of the acute coronary ischemia syndrome, this syndrome showed a unique balloon-like left ventricular (LV) wall motion abnormality at the apex, which did not correlate with the coronary supply of a major coronary vessel. The etiology and pathophysiological basis of this coronary syndrome, which has previously been described in Japan, is still not well understood.
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PMID:[Atypical acute myocardial ischemia syndrome with reversible left ventricular (LV) wall motion abnormalities ("apical ballooning") without significant coronary artery disease]. 1496 82

Under normal conditions, local brain blood flow in young rats determined their individual resistance to ischemia and emotional stress. In low-activity rats predisposed to emotional stress, a level of blood flow was significantly (p<0.05) higher, comparing to high-active animals resistant to emotional stress. An exposure of rats to aggressive- and conflict situation for 18 h was followed by pronounced emotional stress accompanied by the reduction of local cerebral blood flow by 10-15% and abolished individual differences in resistance to cerebral ischemia. Collateral blood flow did not develop in pre-stressed rats during the acute period of cerebral ischemia. The mortality rate reached 90% independently of the animal emotional resistance. In ischemia after 2 h exposure to stress, differences were revealed in the intensity of lipid peroxidation in the brain of animals with divergent emotional resistance. Comparing to stress-resistant rats, in stress-predisposed animals, a level of malonic dialdehyde in the amygdale basal nuclei was 2-fold lower. The results suggest the differences in stress response in animals with various resistance to the effect of adverse factors.
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PMID:[Disregulation of collateral blood flow and lipid peroxidation abnormalities as a cause of negative influence of emotional stress on the course of cerebral ischemia]. 1562 87

Acute myocardial infarction (AMI) is a highly dynamic event, which is associated with marked neuroendocrinological dysfunction in addition to cardiac damage. The immediate trigger for AMI is not precisely known. Studies conducted by Lown, Braunwald, Halberg, Otsuka and our group have demonstrated a marked increase in sympathetic activity, oxidative stress, and magnesium and potassium deficiency during AMI. Clinical studies have reported an increased incidence of AMI, sudden death and ischemia during first quarter of the day when there is a rapid withdrawal of vagal activity and increase in sympathetic tone. In one case-control study of 202 patients with AMI, there was a significant (P < 0.02) increase in cardiac events in the second quarter of the day compared to other quarters, respectively (16.8%, 41.0%, 13.8%, 28.2% per quarter). This characteristic remained prevalent in both men and women and among patients with and without known AMI (n = 52), diabetes (n = 53) or hypertension (n = 75). Triggers of AMI were noted among 162 (82.2%) of the patients. Neuropsychological mechanisms were observed as follows: emotional stress (45.5%), sleep deprivation (27.7%), cold climate (29.2%), hot climate (24.7%), large meals (47.5%) and physical exertion (31.2%). These triggering factors are known to enhance sympathetic activity and decrease vagal tone, resulting in an increased secretion of plasma cortisol, noradrenaline, aldosterone, angiotension-converting enzyme (ACE), interleukin (IL)-1, -2, -6, -18, and tumor necrosis factor-alpha (TNF-alpha), all of which are are proinflammatory agents. There is also a deficiency in the serum levels of vitamin A, E, and C and magnesium, potassium, melatonin, and IL-10 (an anti-inflammatory agent). In our study, we found a decrease in magnesium, potassium, vitamin A, E, C and beta carotene combined with an increase in thiobarbituric acid-reactive substances (TBARS), MDA and diene conjugates, TNF-alpha and IL-6, all of which are indicators of oxidative damage and proinflammatory activity, respectively.
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PMID:Mechanisms of acute myocardial infarction study (MAMIS). 1575 48

Raynaud's phenomenon (RP) is a vasospastic disease and is characterized by ischemia of the digits, nose, and ears. The vasospasm can be triggered by cold weather, cold water, or emotional stress and is followed by triphasic color changes. First white color (ischemia), then blue color (congestion and cyanosis), and finally red color change (reactive hyperemia) can be observed. The prevalence is reported to be between 0.5 and 20% in different studies and is dependent on genetic, occupational, and environmental factors. The purpose of our study was to determine the prevalence of RP in an eastern part of Turkey among healthy subjects. A total of 768 people were included in the study. This cross-sectional study was conducted between April 2003 and October 2003 at the University Hospital and at the State Hospital in Van, Turkey. The participants were interviewed and examined to diagnose RP and a questionnaire and color charts were used. Of these 768 patients, 25 women and 20 men were diagnosed to have RP. A female predominance (25/20) was observed. Their mean age was 24.78 +/- 5.71 years. The prevalence of RP was 5.9% in our study population.
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PMID:Raynaud's phenomenon in a healthy Turkish population. 1590 11

Stroke is the culmination of a heterogeneous group of cerebrovascular diseases that is manifested as ischemia or hemorrhage of one or more blood vessels of the brain. The occurrence of many acute cardiovascular events--such as myocardial infarction, sudden cardiac death, pulmonary embolism, critical limb ischemia, and aortic aneurysm rupture--exhibits prominent 24 h patterning, with a major morning peak and secondary early evening peak. The incidence of stroke exhibits the same 24 h pattern. Although ischemic and hemorrhagic strokes are different entities and are characterized by different pathophysiological mechanisms, they share an identical double-peak 24 h pattern. A constellation of endogenous circadian rhythms and exogenous cyclic factors are involved. The staging of the circadian rhythms in vascular tone, coagulative balance, and blood pressure plus temporal patterns in posture, physical activity, emotional stress, and medication effects play central and/or triggering roles. Features of the circadian rhythm of blood pressure, in terms of their chronic and acute effects on cerebral vessels, and of coagulation are especially important. Clinical medicine has been most concerned with the prevention of stroke in the morning, when population-based studies show it is of greatest risk during the 24 h; however, improved protection of at-risk patients against stroke in the early evening, the second most vulnerable time of cerebrovascular accidents, has received relatively little attention thus far.
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PMID:Circadian variation in stroke onset: identical temporal pattern in ischemic and hemorrhagic events. 1607 46

Local cerebral blood flow in the left hemisphere decreased most significantly in low-resistant Wistar rats preexposed to emotional stress. Deltaran selectively increased blood flow in the left hemisphere and improved blood supply to neuronal activity unit of the brain in these animals. This drug prevented progressive decrease in local cerebral blood flow in both hemispheres during the acute stage of ischemia. The effect of Deltaran was related to modulation of collateral blood flow and adequate blood supply to neuronal activity unit in the brain tissue. Deltaran decreased the mortality rate (by 62%) and alleviated the symptoms of cerebral ischemia. The positive effect of Deltaran was more pronounced in the left hemisphere.
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PMID:Deltaran prevents an adverse effect of emotional stress on the course of cerebral ischemia in low-resistant animals. 1718 Oct 53

Mental and emotional stress can provoke transient ischemia and acute coronary syndrome in vulnerable patients. Furthermore, those patients so provoked are at increased risk for recurrent cardiac events and early death. Viable psychological treatments to improve prognosis exist, and preliminary trials demonstrate their efficacy with regard to short- and long-term outcomes, as well as economic savings. These findings heighten the need for efforts directed toward the complete identification of the differential pathophysiology of mental stress-induced ischemia, with an eye toward development of diagnostic tests and establishment of risk stratification algorithms that can be applied in the clinical setting. Ongoing research in this vein is identifying unique aspects of the brain-heart relationship during mental stress that underlie the cognitive and emotional aspects of mental stress, and the "dow nwind" pathways by which distinct patterns of brain activity during mental stress can provoke otherwise silent myocardial ischemia. This research is making important contributions to the larger clinical goals associated with diagnostic testing, risk stratification, and treatment of patients at risk for mental stress-induced ischemia and poorer prognosis.
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PMID:The heart-brain interaction during emotionally provoked myocardial ischemia: implications of cortical hyperactivation in CAD and gender interactions. 1745 47


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