Genetic diversity of yacon accessions using ISSR markers.

Yacon cultivation has been intensified and the investigations of this crop have increased at the scientific, agricultural, and social levels because the roots of yacon show beneficial properties for human health, such as reducing cholesterol and glucose blood levels. Since the investigations involving yacon are very recent, there is little information available in terms of the genetic characterization of the cultivated genotypes. In view of the lack of information on the accessions cultivated in the State of Espírito Santo, Brazil, this pioneering study aimed to characterize 60 accessions cultivated in the state using ISSR yacon markers with emphasis on identifying the genetic diversity among the materials. The 20 ISSR primers used produced a total of 82 fragments, 39.6% of which presented polymorphism. The number of fragments per primer ranged from 1 to 10. The dissimilarity values ranged from 0 to 0.54 according to the Jaccard coefficient. A dendrogram was generated in which the accessions were divided into 3 groups; group 1 contained 58 individuals and groups 2 and 3 had only one individual in each group. The clustering of 58 accessions in a single group shows the low diversity in the materials examined. This low diversity indicates that new genotypes must be introduced in order to promote increased variability, which would minimize the adverse effects caused by biotic and abiotic factors.

Coronary hemodynamics and myocardial metabolism in patients with syndrome X: response to pacing stress.

Coronary hemodynamics, myocardial metabolism and left ventricular function at rest and after incremental atrial pacing were evaluated in 12 patients with stress-induced angina and ST segment depression, angiographically normal coronary arteries and no evidence of spasm, generally labeled as syndrome X, and in 10 normal subjects. At baseline study, great cardiac vein flow was comparable in patients and control subjects. During pacing, an equivalent rate-pressure product was reached in the two groups, but the slope of the relation between rate-pressure product and great cardiac vein flow was significantly less steep in patients than in normal subjects (0.0027 vs. 0.0054 ml/mm Hg.beat, p less than 0.001). Nevertheless, the left ventricular ejection fraction was comparable in both groups at rest (66 +/- 6% vs. 71 +/- 7%, p = NS) and during pacing (71 +/- 7% vs. 66 +/- 5%, p = NS). At baseline study, myocardial glucose extraction was more efficient in patients with syndrome X (p less than 0.05), but net myocardial exchange of pyruvate and alanine was, respectively, smaller and greater than in control subjects. Lactate was extracted to a similar extent in the two groups and in no instance was net lactate release observed during pacing or recovery. During pacing and recovery, patients with syndrome X showed net pyruvate release, unlike the control subjects in whom net pyruvate exchange was positive. In addition, patients with syndrome X continued to show net myocardial extraction of alanine during spacing and recovery, whereas normal subjects produced alanine throughout the study. Myocardial carbohydrate oxidation increased significantly during maximal pacing in normal subjects but not in patients, in whom it always remained below (p less than 0.01) the concurrent rate of myocardial uptake of carbohydrate equivalents (glucose, lactate, pyruvate, alanine). Myocardial energy expenditure was significantly lower in patients than in control subjects at maximal rate-pressure product levels (p less than 0.01). The metabolic pattern in patients with syndrome X therefore is not consistent with classic ischemia, although differences in the net exchange of circulating substrates (glucose, pyruvate, alanine) can be demonstrated. Thus, in patients with syndrome X, the symptoms, electrocardiographic signs and impairment in the increase in great cardiac vein flow during pacing coexist with preserved global and regional left ventricular function and myocardial energy efficiency.

Coronary vasodilation is impaired in both hypertrophied and nonhypertrophied myocardium of patients with hypertrophic cardiomyopathy: a study with nitrogen-13 ammonia and positron emission tomography.

To assess regional coronary reserve in hypertrophic cardiomyopathy, regional myocardial blood flow was measured in 23 patients with hypertrophic cardiomyopathy and 12 control subjects by means of nitrogen-13 ammonia and dynamic positron emission tomography. In patients with hypertrophic cardiomyopathy at baseline study, regional myocardial blood flow was 1.14 +/- 0.43 ml/min per g in the hypertrophied (20 +/- 3 mm) interventricular septum and 0.90 +/- 0.35 ml/min per g (p less than 0.05 versus septal flow) in the nonhypertrophied (10 +/- 2 mm) left ventricular free wall. These were not statistically different from the corresponding values in control subjects (1.04 +/- 0.25 and 0.91 +/- 0.21 ml/min per g, respectively, p = NS). After pharmacologically induced coronary vasodilation (dipyridamole, 0.56 mg/kg intravenously over 4 min), regional myocardial blood flow in patients with hypertrophic cardiomyopathy increased significantly less than in control subjects both in the septum (1.63 +/- 0.58 versus 2.99 +/- 1.06 ml/min per g, p less than 0.001) and in the free wall (1.47 +/- 0.58 versus 2.44 +/- 0.82 ml/min per g, p less than 0.001). In addition, patients with hypertrophic cardiomyopathy who had a history of chest pain had more pronounced impairment of coronary vasodilator reserve than did those without a history of chest pain. After dipyridamole, coronary resistance in the septum decreased by 38% in patients without a history of chest pain, but decreased by only 14% in those with such a history (p less than 0.05). Coronary resistance in the free wall decreased by 45% in patients without and by 27% in those with a history of chest pain (p = 0.06).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of ergotamine on myocardial blood flow in migraineurs without evidence of atherosclerotic coronary artery disease.

The effects of intravenous ergotamine (0.25 mg) on basal and hyperemic (dipyridamole) myocardial blood flow (MBF), measured with positron emission tomography and H2(15)O, were assessed in 15 migraineurs in a double-blind, randomized, placebo controlled, crossover study. Ergotamine produced a 27% reduction in hyperemic MBF (2.62 +/- 0.11 vs 3.72 +/- 1.05 ml x min(-1) x g(-1); p <0.05), a 31% reduction in the coronary vasodilator reserve (1.81 +/- 0.50 vs 2.71 +/- 1.15; p <0.01), and a 55% increase in minimal coronary resistance (42.2 +/- 15 vs 26.7 +/- 8 mm Hg x min x ml(-1) x g(-1); p <0.001), suggesting vasoconstriction of the coronary microcirculation.

Predictive value of dobutamine echocardiography and positron emission tomography in identifying hibernating myocardium in patients with postischaemic heart failure.

OBJECTIVE: To compare the predictive value of dobutamine echocardiography (DE) and positron emission tomography (PET) in identifying reversible chronic left ventricular (LV) dysfunction (hibernating myocardium) in patients with coronary artery disease (CAD) and overt heart failure. PATIENTS: 30 patients (four women) with CAD and heart failure undergoing coronary artery bypass grafting (CABG). METHODS: Myocardial viability was assessed with DE (5 and 10 micrograms/kg/min) and PET with [18F] 2-fluoro-2-deoxy-D-glucose (FDG) under hyperinsulinaemic euglycaemic clamp. Regional (echo) and global LV function (MUGA) were assessed at baseline and six months after CABG. RESULTS: 192 of the 336 (57%) dysfunctional LV segments improved function following CABG (hibernating) and the LV ejection fraction (EF) increased from 23(7) to 32(9)% (p < 0.0001) (in 17 patients > 5%). DE and PET had similar positive predictive values (68% and 66%) in the identification of hibernating myocardium, but DE had a significantly lower negative predictive value than PET (54% v 96%; p < 0.0001). A significant linear correlation was found between the number of PET viable segments and the changes in EF following CABG (r = 0.65; p = 0.0001). Stepwise logistic regression identified the number of PET viable segments as an independent predictor of improvement in EF > 5%, whereas the number of DE viable segments, the baseline LVEF, and wall motion were not. CONCLUSIONS: DE has a higher false negative rate than PET in identifying recoverable LV dysfunction in patients with severe postischaemic heart failure. The amount of PET viable myocardium correlates with the functional outcome following CABG.

A report system for PET assessment of myocardial viability.

Coronary bypass surgery can improve the prognosis of patients with heart failure due to coronary artery disease. However, these patients have a high operative risk and should be operated on only if they have a sizeable amount of viable tissue (i.e. asynergic myocardium) that can recover contractile function following coronary revascularization. In the clinical setting, regional wall motion is usually evaluated by two-dimensional echocardiography, whereas retained metabolic activity assessed by positron emission tomography (PET) and 18F-fluorodeoxyglucose is a well-established means for the evaluation of myocardial viability. Unfortunately, the two-dimensional echocardiography and PET reports are often different, and this renders the matching of information difficult and the estimation of the risk-benefit ratio of the operation unreliable. In this paper, we present a report system for the evaluation of myocardial viability with PET. We divided the left ventricle into 16 segments following the proposal of the American Society of Echocardiography for wall motion analysis by two-dimensional echocardiography. Following this partition, three portions of the left ventricle are identified along the long axis: basal, mid and apical. Each plane of the basal and mid portions is automatically divided into six segments with the super-imposition of a radial divider over the short-axis images. Similarly, each plane of the apical portion is automatically divided, but into four segments. This partition of the left ventricle permits a precise match between the information on wall motion obtained with two-dimensional echocardiography and that on viability obtained with PET.

[The evaluation of the appropriateness of instrumental exams in cardiology. The case of echocardiography]. / La valutazione dell'appropriatezza degli esami strumentali in cardiologia. Il caso dell'ecocardiografia.

BACKGROUND: The aim of this study was to evaluate the appropriateness and utility rates of echocardiograms performed in 309 patients in an outpatient clinical setting. METHODS: Data were collected by means of a questionnaire filled in by the cardiologists who performed the examinations. Appropriateness was evaluated according to international guidelines and scored as class I: appropriate, class II: doubtful appropriateness, class III: inappropriate; the exam was deemed useful if it was able to influence the clinical decision-making; normalcy rate was also checked. The relationship between both the referring physicians and motivation of the exam and its appropriateness, and the relationship between appropriateness and both the normalcy rate and utility of the exam were assessed. RESULTS: An echocardiogram was requested by the cardiologist in 46% of patients; the more common reasons for the exam were arterial hypertension (26%), cardiac murmur (18%), palpitations (15%), and known coronary artery disease (10%). The echocardiogram was appropriate (class I) in 25% of patients, doubtfully appropriate (class II) in 39% of patients and inappropriate (class III) in 36% of patients. The appropriateness rate between the cardiologists was similar to that of other prescribing clinicians (p = NS). The highest class III rate was found in patients with hypertension, while the highest class I rate was found in patients with a cardiac murmur (p < 0.01). Normalcy rate was lower in class I than in class II and III exams (p < 0.001). The utility rate was higher in class I (76%) than in class II (13%) and III (< 1%) exams (p < 0.01). CONCLUSIONS: International guidelines can be used effectively and safely to identify (not to prescribe) the useless echocardiograms.

Forearm vasodilatory capacity in patients with syndrome X: a comparison with normal and hypertensive subjects.

Minimal forearm vascular resistances during maximal postischaemic vasodilation were measured in normotensive subjects with syndrome X, a condition characterized by angina and normal coronary arteries, in which a reduced coronary and systemic vasodilatory capacity has been reported. Age- and sex-matched normals and essential hypertensives constituted the control groups. The syndrome X patients had a significantly higher minimal forearm vascular resistance than the normals, indicating that arteriolar alterations may occur in the normotensive state and therefore cannot be considered solely as a consequence of hypertension.

[Microcirculation and remodelling]. / Microcircolo e "remodelling".

Acute myocardial infarction can produce alterations in the topography of the left ventricle both in the infarcted and remote areas. These changes as a whole, have been termed ventricular remodelling. Attention has been focused on myocyte alterations due to the remodelling process, but the myocardial wall also contains fibroblasts, which produce collagen and elastin fibers, and endothelial and smooth muscle cells which are the main constituents of the vascular wall. In left ventricular hypertrophy, a form of myocardial remodelling, structural changes of myocytes, cardiac interstitium as well as the coronary microcirculation have been found (vascular remodelling). In vivo, the function of coronary microcirculation can be evaluated by measuring myocardial blood flow and coronary reserve. In fact the study of coronary reserve in patients with left ventricular hypertrophy disclosed microcirculatory dysfunction which probably represents the functional counterpart of the structural changes already described. Positron emission tomography (PET) can noninvasively quantitate myocardial blood flow and coronary reserve in humans. Recently studies with PET disclosed microcirculatory alterations also in patients with coronary artery disease (CAD) in the absence of gross myocardial hypertrophy. In particular, after myocardial infarction, coronary vasodilator capacity has been shown to be impaired not only in the infarcted areas but also in the remote ones subtended by angiographically normal vessels. A blunted coronary reserve has been identified with PET also in remote regions from ischemia in patients with stable angina and single vessel CAD.

[Evaluation of the cost-effectiveness of thrombolytic therapy in acute myocardial infarct using tissue plasminogen activator or streptokinase:the Italian perspective]. / Valutazione costi-efficacia della terapia trombolitica nell'infarto miocardico acuto con attivatore tissutale del plasminogeno o con streptochinasi: la realtà italiana.

UNLABELLED: The GUSTO trial demonstrated that tPA is more effective than streptokinase in the therapy for acute myocardial infarction (AMI). Although tPA is much more expensive than streptokinase some recent analyses have demonstrated that the use of this drug is also cost-effective. However, the cost of the two drugs is different in Italy and USA. Moreover, the difference of the efficacy of the two drugs varies greatly among subgroups of patients with AMI. The aim of this study was to assess the cost-effectiveness of the exclusive use of tPA and streptokinase in the general population and in subgroups of patients divided according to age and site of AMI, using the costs of the drugs in Italy (streptokinase 100,600 and tPA 1,524,300 Italian Liras (ItL)/treatment). METHODS: The results of the GUSTO trial (30 day-mortality) obtained in the general population and subgroups (< or = 75 years and > 75 years; anterior AMI and non-anterior AMI) were applied to patients enrolled in the GISSI-2 trial. The number of lives saved and the incremental costs for each life saved were calculated for the use of tPA in respect to the use of streptokinase. Results are referred to the treatment of 1000 patients. RESULTS: In the general population, in respect to the use of streptokinase, the use of tPA would save 10 lives at an incremental cost of 142.370 millions ItL/life saved. The use of tPA in patients aged < or = 75 years would save 11 patients at the incremental cost of 129.427 millions ItL/life saved, while the use of tPA in patients aged > 75 years would save 13 patients at the incremental cost of 109.515 millions ItL/life saved. In anterior AMI, tPA can save 19 patients at the additional cost of 74.932 millions ItL/life saved, while in non-anterior AMI it can save 6 patients at the additional cost of 237.238 millions ItL/life saved. A subgroup analysis demonstrated that 9 lives can be saved with the use of tPA in anterior AMI and streptokinase in non-anterior AMI at the cost of 49.038 millions ItL/life saved, in respect to the exclusive use of streptokinase. CONCLUSIONS: 1. The cost-effectiveness ratio of tPA in the general population with AMI is comparable to that of other expensive therapies (< 150 millions ItL/life saved). 2. However, a strategy implying a selective use of the two drugs is far more cost-effective (< 50 millions ItL/life saved).

Effect of alpha 1-adrenoceptor blockade on resting and hyperemic myocardial blood flow in normal humans.

In the present study we aimed to assess the effect of alpha 1-adrenoceptor blockade on resting and hyperemic myocardial blood flow in normal humans. Myocardial blood flow, at baseline and after dipyridamole, was measured with positron emission tomography and 15O-labeled water in 11 normal volunteers at control and during alpha 1-blockade with doxazosin. Baseline myocardial blood flow during alpha 1-blockade was not different from control, whereas coronary resistance was significantly lower (73.48 +/- 18.31 vs. 89.84 +/- 27.96 mmHg.min.ml-1.g-1; P < 0.05). After dipyridamole, myocardial blood flow during alpha 1-blockade was significantly higher (3.50 +/- 0.75 vs. 2.58 +/- 0.54 ml.min-1.g-1; P < 0.01) and coronary resistance lower (25.30 +/- 7.37 vs. 33.89 +/- 7.04 mmHg.min.ml-1.g-1; P < 0.01) compared with control. In conclusion, in normal humans, dipyridamole-induced increase in myocardial blood flow is limited by alpha 1-mediated coronary vasoconstriction.

[Total atrioventricular block as the primary clinical manifestation of undiagnosed aortic dissection]. / Blocco atrioventricolare totale come manifestazione clinica principale di dissecazione aortica non diagnosticata.

We describe the case of a 54-year-old male who was examined due to light chest pain experienced the previous day. The man was admitted to the cardiology division for the presence of a complete atrioventricular block. On admission the echocardiogram showed a large aortic regurgitation not present two years earlier. Suspecting an aortic dissection we performed a transesophageal echocardiography and a contrast computerized tomography: the two examinations were negative. The next days the patient had two episodes of acute pulmonary edema so he was transferred to the regional reference hospital where an hemodynamic unit and cardiac surgery division were available. There, he repeated a transesophageal echocardiography which was negative. The man had aortic valve replacement without angiography for his very critical condition. The surgeon identified a small aortic dissection, just above the aortic valve plane, which was responsible for valve leaflets prolapse and aortic regurgitation; the hematoma deepened towards the interatrial septum and atrioventricular junction justifying the atrioventricular block. In conclusion, a small aortic dissection can offer an atypical picture, and in this condition even very valuable diagnostic techniques may fail the diagnosis.

Effect of alpha1-adrenoceptor blockade on coronary vasodilator reserve in cardiac syndrome X.

We sought to test the response of the coronary microcirculation to alpha-adrenoceptor blockade in patients with syndrome X (angina, ischemia-like stress electrocardiogram, and a normal coronary arteriogram). The response of the microcirculation was assessed by quantification of coronary vasodilator reserve (the ratio of hyperemic to resting myocardial blood flow). We investigated 28 patients with syndrome X [18 women, age 54.4 (7.6) years]. Myocardial blood flow was measured at rest and after dipyridamole by using positron emission tomography with H(2)15O. The measurements were made before and after treatment for 10 days with doxazosin (1 mg o.d. for 3 days, followed by 2 mg o.d. for 7 days) or a matched placebo, similarly administered. Patients were randomized to alpha1-blockade or to placebo in double-blind fashion. No significant differences were demonstrable between syndrome X patients treated with doxazosin and those receiving placebo, with respect to resting myocardial blood flow, myocardial blood flow after dipyridamole, or coronary vasodilator reserve (the ratio of the latter two). In addition, no relations were demonstrable among myocardial blood flow, coronary vasodilator reserve, development of chest pain after dipyridamole, or development of ischemia-like ECG changes. Doxazosin had no effect on the perception of chest pain after dipyridamole. No differences were found between the effects of alpha1-blockade with doxazosin or those of placebo with respect to myocardial blood flow in syndrome X. The values obtained for myocardial blood flow and coronary vasodilator reserve for the patients were within the normal range. The data do not support the case for alpha1-mediated vasoconstriction having an etiologic role in the chest pain of syndrome X.

[An economic assessment of the use of abciximab as a coronary angioplasty preparation in the Italian health-care context]. / Valutazione economica dell'uso dell'abciximab come preparazione all'angioplastica coronarica nel contesto sanitario italiano.

UNLABELLED: Drugs blocking platelet glycoprotein IIb/IIIa receptors (anti-GP IIb/IIIa) have been used effectively to prevent thrombotic events after percutaneous transluminal coronary angioplasty (PTCA). However, the high cost of these drugs calls for an economic evaluation before they can be used systematically within the context of the Italian health-care system. METHODS: The systematic review of three studies (EPIC, EPILOG, CAPTURE) that evaluated the effectiveness of abciximab (the only anti-GP IIb/IIIa drug commercially available in Italy) demonstrated that this drug can prevent thrombotic events (death, myocardial infarction, repeated PTCA, bypass surgery) at six months after PTCA (RR 0.84; IC 95% 0.77-0.91; number needed to treat for the composite end-point 21). We performed an economic evaluation of the use of abciximab, taking into account the cost the drug (2,561,100 Italian lire [ITL]/patient) and the number of events prevented. We calculated the mean cost-effectiveness ratio (cost of each patient without events at six months after PTCA), the incremental cost-effectiveness ratio (cost of each event prevented at six months after PTCA) and the cost of each year of life saved at six months after PTCA. RESULTS: The mean cost-effectiveness ratio was 16.6 million ITL/patient (versus 15.4 million ITL/patient without the use of the drug); the incremental cost-effectiveness ratio was 34.3 million ITL/event prevented; the cost of each year of life saved was 32.3 million ITL. CONCLUSIONS: With abciximab preventing thrombotic events at six months after PTCA, the cost of each patient without events and the cost of each event prevented at six months are within the range of other pharmaceutical procedures in cardiology (e.g. thrombolysis in acute myocardial infarction with tissue plasminogen activator). Our analysis supports the case for the systematic use of abciximab in patients undergoing PTCA.

[An aggressive exercise test is suitable for myocardial scintigraphy]. / Un test da sforzo aggressivo adatto per la scintigrafia miocardica.

Exercise myocardial scintigraphy is frequently used as a second step tool in the assessment of coronary artery disease. Little attention has been paid on the exercise protocol used as a stress during scintigraphy. However, the diagnostic accuracy of the test is better if higher heart rate is achieved. The aim of this study was to evaluate if an aggressive exercise protocol was safe and more effective than a standard protocol in achieving higher heart rate. Eighty-four patients (64 men and 20 women, mean age 56 +/- 10 years, range 34-78 years) underwent a standard exercise test (cycloergometry; SET: 25 W increments every 2 min starting from 25 W load) and an aggressive exercise test (AET: 50 W increments every 2 min starting from 50 W load); during AET a myocardial scintigraphy (Tc-99m sestamibi; SPECT) was performed. Heart rate and blood pressure were monitored during the tests and the rate-pressure product was calculated. No patients had major adverse events during either tests. During AET with respect to the SET, higher maximal heart rate (142 +/- 15 vs 134 +/- 16 b/min; p < 0.01) and rate-pressure product (27,293 +/- 4341 vs 25,773 +/- 6690 b/min x mmHg; p < 0.05) were obtained. During AET higher number of maximal (55/84 vs 34/84; p < 0.05) and positive tests (45/84 vs 29/84; p < 0.05) were detected with respect to the SET. Using myocardial scintigraphy as a reference test, the diagnostic accuracy of the SET and AET was 54 and 73% respectively. In conclusion, an aggressive protocol during exercise stress test can safely be used to obtain a greater number of maximal and positive exercise tests.

[Comparison of lidoflazine and quinidine in the conversion to sinusal rhythm in atrial fibrillation of recent onset]. / Confronto fra lidoflazina e chinidina nella conversione a ritmo sinusale della fibrillazione atriale di recente insorgenza.

In order to compare the efficacy of oral lidoflazine (240 mg/die) and oral quinidine (1200 mg/die) in re-establishing sinus rhythm, we studied 115 patients (mean age 63.8 years; range 32-91) with atrial fibrillation of recent onset (less than 3 months). Patients with cardiac failure, acute myocardial infarction, severe intraventricular conduction disturbances, kaliemia less than 3.8 mEq/L or digoxinemia greater than 2 ng/ml were not included. Patients were randomly given one of the 2 drugs, until conversion to sinus rhythm was achieved, severe side effects occurred or for a maximum therapy of 5 days. No significant differences were present between the 2 groups in terms of age, male/female ratio, duration of atrial fibrillation, presence of an enlarged left atrium, presence of organic heart disease (or arterial hypertension) or digitalis therapy. Sinus rhythm resumption was obtained in 41/58 (71%) patients treated with quinidine and in 47/57 (82%) patients treated with lidoflazine (p = ns). In successful cases, the mean treatment time was 79 +/- 33 (SD) hours for quinidine and 66 +/- 36 hours for lidoflazine (p = ns). Both drugs showed the same efficacy in 3 subgroups of patients in whom the arrhythmia had different duration (less than 24 hours; between 24 hours and 3 days; more than 3 days). Treatment was stopped in 5 patients receiving quinidine (gastrointestinal side effects) and in 3 patients receiving lidoflazine (frequent premature ventricular beats in 2 and polymorphic ventricular tachycardia of the "torsade de pointes" type in 1).(ABSTRACT TRUNCATED AT 250 WORDS)

[Psychological and social aspects in women with syndrome X]. / Aspetti psicologici e sociali nelle donne con sindrome X.

A sizeable proportion (20-30%) of patients undergoing coronary arteriography for a chest pain syndrome are found to have angiographically normal coronary arteries. Some of these subjects (10-15%) have ischemic-like electrocardiographic changes during stress and no evidence of spasm of the epicardial coronary arteries (syndrome X). The vast majority of these patients are middle aged females. In the present investigation we evaluated the psychological and social characteristics of a group of patients with syndrome X (PX, n = 30). The results obtained in the PX group were compared with those in a sex and age matched group of patients with angiographically proven coronary artery disease (PI, n = 32) and with those in a group of control subjects (C, n = 29). Two original questionnaires were employed to collect the demographic and family data. The psychological data were obtained through the following 4 questionnaires: Symptom Rating Test (SRT); Symptom Questionnaire (SQ); Illness Behaviour Questionnaire (IBQ); Maudsley Personality Inventory (MPI). The results of our study indicated that in most of the patients with syndrome X the psychological and social conditions are similar and they are not compatible with a satisfactory lifestyle. In most cases both family and social difficulties are present, which impose excessive workload and distress on the patients. Very often the beginning of the chest pain history tends to coincide with the periods of greatest stress and with the occurrence of dramatic events in the family. On the other hand, the onset of symptoms often has the effect of releasing some of the environmental pressure on the patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Metabolic markers of stress-induced myocardial ischemia.

The human heart in the fasting state extracts free fatty acids (FFA), glucose, lactate, pyruvate, and ketones from circulating blood. The utilization of FFA accounts for most of the oxygen consumed and energy produced at rest. Patients with angiographically demonstrable coronary artery disease and stable angina pectoris have a resting myocardial metabolism similar to that of normal individuals. During atrial pacing in normal persons, there is a significant enhancement of glucose uptake but that of FFA is unchanged, and the oxidation of carbohydrates accounts for more than 60% of the energy produced. In patients with stable angina, myocardial perfusion becomes regionally inadequate during stress. Despite the increase of myocardial glucose utilization, carbohydrate oxidation is negligible. Pyruvate will not be oxidized but in the presence of increased amounts of reduced coenzymes will be reduced to lactate. In addition, a greater amount of alanine will be released by the myocardium through the transamination of pyruvate, with a concomitantly greater uptake of glutamate that serves as the NH2 donor. In addition, glutamate may be used as an anaerobic fuel through conversion to succinate coupled with GTP formation. Although coronary hemodynamics, including myocardial perfusion, return to baseline within a few minutes after stress, a longer time course is needed for myocardial metabolism to become normal. In particular, myocardial utilization of exogenous glucose remains higher well after the normalization of hemodynamic parameters. This is more pronounced in postischemic myocardium, but it also occurs in nonischemic muscle, and glucose is presumably used for rebuilding glycogen stores that were depleted during ischemia.