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With an ageing population and more people surviving heart attacks there are increasing numbers of people living with heart failure. Readmissions to hospital are often prolonged and costly. A number of nurse-led schemes have been successful in tackling the preventable causes of hospital readmissions and helping patients achieve a better quality of life in the community.
Anaerobic metabolism in heart muscle plays a role in maintenance of myocardial preservation only during ischemia or hypoxia. In an ischemic state, such as during a heart attack or even during the induced ischemia of open heart surgery, there is impairment of blood flow to the myocardium. The major energy-yielding process in the heart is through the metabolism of glucose and lipids by oxidative reactions. Under anaerobic conditions, oxygen is not available to accept the electrons in the metabolic degradation of substrates and anaerobic glycolysis becomes important in the preservation of myocardial viability during the ischemic process. Unfortunately, the accumulated products of glycolysis, namely protons and lactate, work to inhibit glycolysis, ultimately resulting in a depression of anaerobic metabolism. Cardioplegia, as utilized during open heart surgery, has the effect of inducing instantaneous induction of myocardial mechanical and electrical arrest with a maximal inhibition of the energy utilizing metabolic processes. This effectively reduces substrate utilization and prevents the deleterious consequences of the ischemic process. Cardioplegia is most effective when combined with the additive properties of hypothermia, which plays a significant role in decreasing myocardial metabolism. However, during prolonged hypothermic cardioplegic arrest, sufficient ATP cannot be maintained for cellular integrity and anaerobic glycolysis becomes of increasing importance for maintenance of myocardial preservation. This presentation deals with the mechanics of aerobic versus anaerobic metabolism during the ischemic process of open heart surgery.
The Worcester Heart Attack Study is an ongoing population-based investigation examining changes over time in the incidence and case-fatality rates of acute myocardial infarction (AMI) in residents of metropolitan Worcester, Massachusetts. Using this large population-based database of patients with independently validated AMI, we examined the impact of the September 11th tragedy on the occurrence rates of AMI in residents of greater Worcester presenting to all area hospitals during 2001 compared with rates in the previous 10 years.
"Chronoastrobiology: are we at the threshold of a new science? Is there a critical mass for scientific research?" A simple photograph of the planet earth from outer space was one of the greatest contributions of space exploration. It drove home in a glance that human survival depends upon the wobbly dynamics in a thin and fragile skin of water and gas that covers a small globe in a mostly cold and vast universe. This image raised the stakes in understanding our place in that universe, in finding out where we came from and in choosing a path for survival. Since that landmark photograph was taken, new astronomical and biomedical information and growing computer power have been revealing that organic life, including human life, is and has been connected to invisible (non-photic) forces, in that vast universe in some surprising ways. Every cell in our body is bathed in an external and internal environment of fluctuating magnetism. It is becoming clear that the fluctuations are primarily caused by an intimate and systematic interplay between forces within the bowels of the earth--which the great physician and father of magnetism William Gilbert called a 'small magnet'--and the thermonuclear turbulence within the sun, an enormously larger magnet than the earth, acting upon organisms, which are minuscule magnets. It follows and is also increasingly apparent that these external fluctuations in magnetic fields can affect virtually every circuit in the biological machinery to a lesser or greater degree, depending both on the particular biological system and on the particular properties of the magnetic fluctuations. The development of high technology instruments and computer power, already used to visualize the human heart and brain, is furthermore making it obvious that there is a statistically predictable time structure to the fluctuations in the sun's thermonuclear turbulence and thus to its magnetic interactions with the earth's own magnetic field and hence a time structure to the magnetic fields in organisms. Likewise in humans, and in at least those other species that have been studied, computer power has enabled us to discover statistically defined endogenous physiological rhythms and further direct effects that are associated with these invisible geo- and heliomagnetic cycles. Thus, what once might have been dismissed as noise in both magnetic and physiological data does in fact have structure. And we may be at the threshold of understanding the biological and medical meaning and consequences of these patterns and biological-astronomical linkages as well. Structures in time are called chronomes; their mapping in us and around us is called chronomics. The scientific study of chronomes is chronobiology. And the scientific study of all aspects of biology related to the cosmos has been called astrobiology. Hence we may dub the new study of time structures in biology with regard to influences from cosmo- helio- and geomagnetic rhythms chronoastrobiology. It has, of course, been understood for centuries that the movements of the earth in relation to the sun produce seasonal and daily cycles in light energy and that these have had profound effects on the evolution of life. It is now emerging that rhythmic events generated from within the sun itself, as a large turbulent magnet in its own right, can have direct effects upon life on earth. Moreover, comparative studies of diverse species indicate that there have also been ancient evolutionary effects shaping the endogenous chronomic physiological characteristics of life. Thus the rhythms of the sun can affect us not only directly, but also indirectly through the chronomic patterns that solar magnetic rhythms have created within our physiology in the remote past. For example, we can document the direct exogenous effects of given specific solar wind events upon human blood pressure and heart rate. We also have evidence of endogenous internal rhythms in blood pressure and heart rate that are close to but not identical to the period length of rhythms in the solar wind. These were installed genetically by natural selection at some time in the distant geological past. This interpretive model of the data makes the prediction that the internal and external influences on heart rate and blood pressure can reinforce or cancel each other out at different times. A study of extensive clinical and physiological data shows that the interpretive model is robust and that internal and external effects are indeed augmentative at a statistically significant level. Chronoastrobiological studies are contributing to basic science--that is, our understanding is being expanded as we recognize heretofore unelaborated linkages of life to the complex dynamics of the sun, and even to heretofore unelaborated evolutionary phenomena. Once, one might have thought of solar storms as mere transient 'perturbations' to biology, with no lasting importance. Now we are on the brink of understanding that solar turbulences have played a role in shaping endogenous physiological chronomes. There is even documentation for correlations between solar magnetic cycles and psychological swings, eras of belligerence and of certain expressions of sacred or religious feelings. Chronoastrobiology can surely contribute to practical applications as well as to basic science. It can help develop refinements in our ability to live safely in outer space, where for example at the distance of the moon the magnetic influences of the sun will have an effect upon humans unshielded by the earth's native magnetic field. We should be better able to understand these influences as physiological and mechanical challenges, and to improve our estimations of the effects of exposure. Chronoastrobiology moreover holds great promise in broadening our perspectives and powers in medicine and public health right here upon the surface of the earth. Even the potential relevance of chronoastrobiology for practical environmental and agricultural challenges cannot be ruled out at this early stage in our understanding of the apparently ubiquitous effects of magnetism and hence perhaps of solar magnetism on life. The evidence already mentioned that fluctuations in solar magnetism can influence gross clinical phenomena such as rates of strokes and heart attacks, and related cardiovascular variables such as blood pressure and heart rate, should illustrate the point that the door is open to broad studies of clinical implications. The medical value of better understanding magnetic fluctuations as sources of variability in human physiology falls into several categories: 1) The design of improved analytical and experimental controls in medical research. Epidemiological analyses require that the multiple sources causing variability in physiological functions and clinical phenomena be identified and understood as thoroughly as possible, in order to estimate systematic alterations of any one variable. 2) Preventive medicine and the individual patients'care. There are no flat 'baselines', only reference chronomes. Magnetic fluctuations can be shown statistically to exacerbate health problems in some cases. The next step should be to determine whether vulnerable individuals can be identified by individual monitoring. Such vulnerable patients may then discover that they have the option to avoid circumstances associated with anxiety during solar storms, and/or pay special attention to their medication or other treatments. Prehabilitation by self-help can hopefully complement and eventually replace much costly rehabilitation. 3) Basic understanding of human physiological mechanisms. The chronomic organization of physiology implies a much more subtle dynamic integration of functions than is generally appreciated. All three categories of medical value in turn pertain to the challenges for space science of exploring and colonizing the solar system. The earth's native magnetic field acts like an enormous umbrella that offers considerable protection on the surface from harsh solar winds of charged particles and magnetic fluxes. The umbrella becomes weaker with distance from the earth and will offer little protection for humans, other animals, and plants in colonies on the surface of the moon or beyond. Thus it is important before more distant colonization is planned or implemented to better understand those magnetism-related biological- solar interactions that now can be studied conveniently on earth. (ABSTRACT TRUNCATED)
The recent Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) showed that the primary end point, coronary heart disease, was identical in the chlorthalidone, lisinopril, and amlodipine groups. Yet the major conclusion of this trial was that thiazide diuretics are superior in preventing 1 or more major forms of cardiovascular disease and should be preferred for first-line antihypertensive therapy. This conclusion was based solely on an analysis of secondary end points and cost. As evidenced by the dictum to "use thiazides for most patients with uncomplicated hypertension" in the Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, this interpretation of ALLHAT broadly adumbrated these guidelines. Although diuretics will rightfully remain a cornerstone in antihypertensive therapy, we should remember (as we were told by the ALLHAT investigators) that secondary end points are "soft data" that should not form a basis for main conclusions or lead to a labeling of a drug class as preferred.
INTRODUCTION: Nowadays stroke has a dominant place in the structure of neurological morbidity. According to data of the World Health Organization, stroke is the third highest cause of morbidity and mortality in the developed countries of the world, immediately following ischemic heart disease and malignant diseases. The appearance of the disease is influenced by many etiological factors, that is risk factors. Natural risk factors are: heredity, sex, age, geographical and climatic factors. Other diseases being risk factors include: hypertension, heart disease and diabetes. Bad habits as risk factors are: eating habits, obesity, smoking, alcoholism and physical and mental inactivity. The paper presents a review of risk factors, their categorization and the influence of each individual risk factor on the development of stroke. HEREDITY: Hereditary factors have a significant role in development of stroke and they may serve as a basis for determining the person's susceptibility to stroke in a certain period of life. SEX: It has been proved that persons of female sex in the period prior to menopause are less susceptible to atherosclerosis risk and its side effects--ischemic heart disease and stroke. It is due to the fact that in this period of life women have a higher concentration of high-density lipoproteins, which are known to protect blood vessels against atherosclerosis. AGE: The incidence of stroke is higher at an older age, although nowadays there is evidence that younger people may develop the disease as well. CLIMATIC FACTORS: It has been noticed that the frequency and intensity of insult are connected with abrupt changes of the front (weather conditions with certain values of atmospheric factors). A high correlation between the frequency of cerebrovascular insult and abrupt change of the front is evident during spells of warm front in cold months and during spells of cold front in warm months. Moreover, changes during the circadian cycle are of utmost importance. HYPERTENSION: Hypertension is one of the factors contributing to the development of cerebrovascular insult, apart from heart diseases and diabetes. HEART DISEASES: The most frequent heart diseases correlating with stroke are: endocardial diseases, myocardial diseases in the form of chronic heart failure or heart attack, atrial fibrillation, hypertrophy of the left chamber and congestive heart failure. DIABETES MELLITUS: Diabetes as an associated risk factor correlates with stroke. EATING HABITS: A special emphasis is placed on nutrition as a risk factor in development of stroke. Inadequate nutrition contributing to the development of stroke is primarily nutrition which includes a high percentage of fats and leads to hyperlipoproteinemias. Therefore the basic principle in the nutrition of a patient with hyperlipoproteinemias is to limit the overall intake of fats, to reduce the quantity of saturated fats and to increase the intake of unsaturated fatty acids. In order to prevent stroke it is recommended to consume sea fish, legumes rich in diet plant fibres, oats and corn cereals, whole grain rice, fruit and vegetables rich in vitamins C and E. OBESITY: It has been proved that obesity or increase in body weight increases the risk of developing stroke by 1.4 to 2.5 times. SMOKING: Smoking accelerates the process of atherosclerosis leading to the incidence of myocardial and brain stroke. In proportion to the length of smoking and the number of cigarettes, a relative risk of development of stroke goes from 2.4 to 6.1 for men and from 3 to 3.7 for women. ALCOHOL DRINKING: A research performed by Finnish authors has shown that in chronic alcoholism the risk of developing stroke is twice as high in men and five times as high in women in relation to the general population. Alcohol reduces the regional cerebral flow by its toxic effect on the cerebral metabolism and thus induces vasospasm and hemoconcentration. (ABSTRACT TRUNCATED)
Cardiophobia is defined as an anxiety disorder of persons characterized by repeated complaints of chest pain, heart palpitations, and other somatic sensations accompanied by fears of having a heart attack and of dying. Persons with cardiophobia focus attention on their heart when experiencing stress and arousal, perceive its function in a phobic manner, and continue to believe that they suffer from an organic heart problem despite repeated negative medical tests. In order to reduce anxiety, they seek continuous reassurance, make excessive use of medical facilities, and avoid activities believed to elicit symptoms. The relationship of cardiophobia to illness phobia, health anxiety, and panic disorder is discussed. An integrative psychobiological model of cardiophobia is presented which includes previous learning conditions relating to experiences of separation and cardiac disease; deficient and inappropriate behavioural repertoires which constitute a psychological vulnerability for cardiophobic problems; negative life events, stressors, and conflicts in the person's present situation that trigger and contribute to the symptoms; current affective, cognitive, and behavioural symptoms and their stimulus properties; and genetic and acquired biological vulnerability factors. Finally, recommendations for the treatment of cardiophobia are derived from the model and areas of future research are outlined.
A 70-year-old man with adenocarcinoma of the lung suffered from an attack of acute myocardial infarction during hospitalization. Eleven days after the heart attack, clinically obvious disseminated intravascular coagulation (DIC) occurred. The intravascular coagulation abnormalities progressed and eventually the patient died. We suspect that both lung adenocarcinoma and the insult of myocardial infarction may have contributed to the development of DIC in this patient.
Isolated systolic hypertension is a risk factor for the development of stroke, heart attack, and left ventricular hypertrophy, which can result in eventual congestive heart failure. Recent studies have validated the benefits of treatment of isolated systolic hypertension in the elderly and have shown that treatment can reduce the risk for cardiovascular complications. An update on isolated systolic hypertension and the importance of detecting and treating are presented.
BACKGROUND: What people believe about their illness may affect how they cope with it. It has been suggested that such beliefs stem from those commonly held within society. This study compared the beliefs held by people with angina, regarding causation and coping in angina, with the beliefs of their friends who do not suffer from angina. METHODS: Postal survey using the York Angina Beliefs Questionnaire (version 1), which elicits stress attributions and misconceived beliefs about causation and coping. This was administered to 164 people with angina and their non-cohabiting friends matched for age and sex. 132 people with angina and 94 friends completed the questionnaire. RESULTS: Peers are more likely than people with angina to believe that angina is caused by a worn out heart (p < 0.01), angina is a small heart attack (p = 0.02), and that it causes permanent damage to the heart (p < 0.001). Peers were also more likely to believe that people with angina should take life easy (p < 0.01) and avoid exercise (p = 0.04) and excitement (p < 0.01). CONCLUSIONS: The beliefs of the peer group about causation and coping in angina run counter to professional advice. Over time this may contribute to a reduction in patient concordance with risk factor reduction, and may help to create cardiac invalids.
Acute asthma is a very common medical emergency. Thus, a variety of measures are currently used to assess severity; most are logical and seem reasonably effective but have never been scientifically tested in a comprehensive manner. Additionally, simple brief measures are needed for greater specificity in describing variables and in assessing different aspects of asthma. The purpose of this study was to examine the most common clinical and objective measures utilized in the assessment of acute asthma in the emergency department for determining whether these variables comprise separate or distinct dimensions. To carry out the above purpose, we used the multivariate statistical technique of factor analysis. Measures of age, duration of attack, heart rate, respiratory rate, peak expiratory flow (PEF), FVC, FEV1 percent of predicted, accessory-muscle use, dyspnea, wheezing, steroid use, and early response to treatment in 194 patients with acute asthma (mean age = 32.8 +/- 11.9 years) were factor analyzed through the method of principal components. Factors extracted with this method were then rotated orthogonally through the Varimax procedure. The first factor contained the three measures of lung function (PEF, FVC, and FEV1 percent of predicted) and early response of treatment. The second factor extracted contained respiratory rate, accessory-muscle use, and dyspnea. Factor 3 contained heart rate and wheezing, and factor 4 contained age, duration of attack, and steroid use. Exploratory analysis of subgroups (by randomization, by severity of airflow obstruction, and by use of steroids) confirmed the results of the primary analysis. The coefficients of congruence obtained were above 0.90. Early response of treatment measured by the percent variation of FEV1 at 30 min over baseline value significantly correlated with a broad variety of asthma characteristics (PEF, FVC, FEV1 percent of predicted, accessory-muscle use, and duration of attack), resulting in a rather general measure, and suggesting that its measure can be a reliable assessment of acute adult asthma. Finally, early response to treatment was the most important predictor of the patient outcome (r = 0.48, p < 0.00). In summary, the results of this study support the hypothesis that most of the subjective and objective measures utilized in the assessment of patients with acute adult asthma represent separate and nonoverlapping dimensions and provided a useful summary of acute asthma. Early response to treatment in combination with measures of the four identified factors could be included in other acute adult asthma research protocols promoting greater comparable among studies.
Doxazosin mesylate is an alpha1-adrenoceptor antagonist that was used to treat hypertension until a major study (ALLHAT; Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial) showed that it increased the risk of progressing to heart failure. Doxazosin is now being used to treat benign prostatic hyperplasia (BPH). Noradrenaline acts on alpha1-adrenoceptors to contract the smooth muscle in the prostate and bladder, and by opposing these actions, doxazosin is beneficial in BPH. Doxazosin also increases apoptosis in the prostate. Although the standard preparation is suitable for once-daily dosing in BPH, it has to be titrated through three steps to its final dose. The controlled-release gastrointestinal therapeutic system (GITS) formulation of doxazosin is more convenient to use as it only has to be titrated through one step. In the treatment of BPH, standard doxazosin reduced both obstructive and irritative symptoms and increased peak urinary flow rate. The main side effects with doxazosin are those commonly associated with lowering blood pressure, although doxazosin lowers blood pressure to a lesser extent in normotensives than hypertensives. There is some evidence that in addition to being easier to use, doxazosin GITS may cause less adverse effects than the standard preparations. The benefits of doxazosin and the 5alpha-reductase inhibitor, finasteride, may be additive in BPH especially in men with large prostates. Further trials are necessary in order to determine whether doxazosin GITS is superior to other alpha1-adrenoceptor antagonists in BPH.
The Multiple Risk Factor Intervention Trial (MRFIT) was a randomised clinical trial of the preventability of fatal first heart attacks among middle-aged men at high risk of coronary heart disease (CHD). After screening 361,662 men aged 35 to 57 years, 12,866 men currently free of CHD at the upper end of the risk spectrum on the basis of their levels of serum cholesterol, diastolic blood pressure and cigarette smoking were randomised either to 'special intervention' (SI) or to 'usual care' (UC). Those SI men with a sustained diastolic blood pressure greater than or equal to 90mm Hg (following attempted weight loss, if indicated) received pharmacological treatment in the form of a protocol of 'stepped care'. UC men were referred to their usual source of medical care. At the termination of the study - after 6 to 8 years of intervention - no significant differences in overall deaths from CHD or from all causes were observed between the SI and UC groups. However, among the subgroup of individuals who had both a diastolic blood pressure greater than or equal to 90mm Hg and abnormalities of the resting electrocardiogram at baseline there was an excess of deaths from CHD in the SI group compared with the UC group (36 vs 21), and most of the excess deaths were sudden (20 vs 8).
Hemodynamic, ventilatory, and biochemical variables were measured in ten healthy adults and ten panic patients during infusion of 0.5 mol/L of sodium lactate. Physical activity, fitness level, and ambulatory electrocardiograms were also recorded. Lactate infusion doubled cardiac output, increased blood lactate levels by sixfold, and produced hypernatremia, hypocalcemia, and decreased serum bicarbonate levels in both groups but raised arterial pressure only in the patients. The patients hyperventilated before and during the infusion. Physiological responses and somatic complaints with the infusion differed little between the groups, but emotional complaints were six times more frequent among the panic patients. Eight patients but no control subjects interpreted their symptoms as a panic attack. Heart rate increased with only 14 of 31 recorded spontaneous outpatient panic attacks. Sodium lactate infusions appear to produce panic by mimicking the physiology of spontaneous panic. Treatment with cardioactive agents is not indicated in the absence of cardiopulmonary or autonomic nervous system abnormalities.
Twenty-four hour ambulatory electrocardiography was performed on 3,290 survivors of acute myocardial infarction participating in the Beta-Blocker Heart Attack Trial (BHAT). History of myocardial infarction before the qualifying event, congestive heart failure and age were independently associated with the frequency and complexity of ventricular premature beats. Of the 1,640 patients randomized to placebo therapy, 163 died (76 suffered sudden death) during a 25 month average follow-up period. Ventricular ectopic activity was an independent predictor of total mortality after taking into consideration 16 other prognostic factors describing past history, risk factors, physical examination and laboratory investigations. Seven categoric definitions of ventricular ectopic activity predicted mortality, with similar odds ratios ranging from 2.27 to 2.69. A reciprocal relation of the sensitivity and specificity of each definition in predicting mortality was observed. Three clinical criteria (ST depression, cardiomegaly and prior infarction) allowed stratification of patients into four subsets with respective mortality rates of 35.5% (three criteria present), 19.0% (two criteria), 11.5% (one criterion) and 4.7% (none). Presence of ventricular ectopic activity (greater than or equal to 10 ventricular premature beats/h or pairs, ventricular tachycardia or multiform complexes) was associated with higher mortality rates in all four risk strata. The relative risk was higher (3.86) in the lowest risk stratum (mortality 2.4% without and 9.1% with ventricular ectopic activity). Thus, in survivors of acute myocardial infarction, ventricular ectopic activity was more pronounced in patients with prior myocardial infarction and congestive heart failure. It predicted mortality independently of other factors. Although mortality ratios were similar for all seven arrhythmia definitions, a reciprocal relation between sensitivity and specificity of the definitions in predicting mortality existed; ventricular ectopic activity was associated with increased mortality in all risk strata, but with a higher risk ratio in the numerically larger, low risk subset.
UNLABELLED: Abnormal automaticity is the spontaneous beating of cardiac cells with abnormally depolarized resting membrane potentials. The effects of halothane on cardiac arrhythmias caused by abnormal automaticity are controversial, with either antiarrhythmic effects or enhancement of abnormal automaticity reported by different authors. The goal of the present investigation was to clarify the effects of halothane on abnormal automaticity induced by superfusing excised canine Purkinje fibers (PF) with barium chloride. Intracellular microelectrodes recorded action potentials from fibers superfused with buffer solution in a tissue bath. Barium chloride 0.25 mM reduced maximal diastolic potential from -82.1 +/- 5.6 mV to -67.4 +/- 9.4 mV (mean +/- SD, P < 0.05). Fibers developed abnormal automatic rhythms at a rate of 47.1 +/- 5.9 bpm. Halothane, 0.5%-4%, was added to the superfusate. Halothane reduced the rate of firing in a dose-dependent manner, so that abnormal automaticity was abolished by 4% halothane and reduced by lesser concentrations. Serendipitously, during barium superfusion, two additional fibers developed early afterdepolarizations, a cause of triggered arrhythmias in patients with long Q-T syndrome. Halothane abolished early afterdepolarizations in each. In this model of barium toxicity in excised canine PF, halothane antagonized both abnormal automaticity and early afterdepolarizations. IMPLICATIONS: Life-threatening cardiac arrhythmias may occur during anesthesia. An arrhythmia called abnormal automaticity occurs after heart attacks and can be mimicked by adding barium to small segments of heart tissue. Halothane abolished abnormal automaticity in these tissues, which suggests that it or similar agents may benefit patients prone to developing such abnormal rhythms during surgery.
The Confidence Profile Method is a Bayesian method for adjusting and combining pieces of evidence to estimate parameters, such as the effect of health technologies on health outcomes. The information in each piece of evidence is captured in a likelihood function that gives the likelihood of the observed results of the evidence as a function of possible values of the parameter. A posterior distribution is calculated from Bayes formula as the product of the likelihood function and a prior distribution. Multiple pieces of evidence are incorporated by successive applications of Bayes' formula. Pieces of evidence are adjusted for biases to internal or external validity by modeling the biases and deriving "adjusted" likelihood functions that incorporate the models. Likelihood functions have been derived for one-, two- and multi-arm prospective studies; 2 x 2, 2 x n and matched case-control studies, and cross-sectional studies. Biases that can be incorporated in likelihood functions include crossover in controlled trials, error in measurement outcomes, patient selection biases, differences in technologies, and differences in length of follow-up. Effect measures include differences of rates, ratios of rates, and odds ratios. The elements of the method are illustrated with an analysis of the effect of a thrombolytic agent on the difference in probability of 1-year survival after a heart attack.
Platelet number and alpha-granule membrane protein (GMP-140) level on platelet surface were determined in 20 patients with acute myocardial infarction (AMI) and 20 normal subjects. The results showed that platelet number decreased significantly after AMI, especially on the second day after onset and that the level of GMP-140 increased rapidly after AMI and reached a peak on the second after the attack. Both returned to the normal on the 5-7th day after the heart attack. Correlative analysis between increase of serum CK-MB and platelet number was negative (r = -0.6123, P < 0.005), and positive between that and GMP-140 level (r = 0.5895, P < 0.01). Platelet number decreased markedly in cases with heart failure and cardiac death. The results indicate that platelets are involved in the pathological process of AMI.