José A. Ferrero

Mechanism of Free Radical Production in Exhaustive Exercise in Humans and Rats; Role of Xanthine Oxidase and Protection by Allopurinol

Exhaustive exercise generates free radicals. However, the source of this oxidative damage remains controversial. The aim of this paper was to study further the mechanism of exercise‐induced production of free radicals. Testing the hypothesis that xanthine oxidase contributes to the production of free radicals during exercise, we found not only that exercise caused an increase in blood xanthine oxidase activity in rats but also that inhibiting xanthine oxidase with allopurinol prevented exercise‐induced oxidation of glutathione in both rats and in humans. Furthermore, inhibiting xanthine oxidase prevented the increases in the plasma activity of cytosolic enzymes (lactate dehydrogenase, aspartate aminotransferase, and creatine kinase) seen after exhaustive exercise. Our results provide evidence that xanthine oxidase is responsible for the free radical production and tissue damage during exhaustive exercise. These findings also suggest that mitochondria play a minor role as a source of free radicals during exhaustive physical exercise.

Guías de práctica clínica de la Sociedad Española de Cardiología en pruebas de esfuerzo

La mayor parte de las pruebas de esfuerzo se realizan a pacientes adultos con cardiopatia isquemica en estudio o ya conocida. En los ultimos anos se ha producido la incorporacion de las tecnicas de imagen en este campo, mejorando asi la informacion aportada por la prueba de esfuerzo convencional. Pero cada vez existen mas situaciones que escapan a esta norma general, tanto en sujetos sanos (asintomaticos, atletas, discapacitados, etc.) como en pacientes con cardiopatias diferentes de la isquemica (insuficiencia cardiaca congestiva avanzada, hipertension, trastornos del ritmo, cardiopatias congenitas etc.). Todos estos aspectos justifican un documento de consenso en Espana, necesariamente multidisciplinario. Este documento revisa en profundidad la metodologia de las pruebas de esfuerzo convencionales, sin olvidar las realizadas con determinacion de consumo de oxigeno. El papel de esta exploracion en el manejo de la cardiopatia isquemica, asi como las aplicaciones de las tecnicas de imagen al campo del estres, ocupan un lugar fundamental en esta revision. Por ultimo, se analiza la utilidad de las pruebas de esfuerzo en diversas cardiopatias no isquemicas y en diferentes poblaciones de sujetos sanos.

Valor de la prueba de esfuerzo precoz en un protocolo de unidad de dolor torácico

Early exercise testing (first 24 hours) was evaluated in the stratification of patients seen in the emergency room for chest pain. One hundred and forty-two consecutive patients without ischemia in the ECG or troponin I elevation were included. Ninety-two patients were discharged after the exercise testing (group I, 82 negative and 10 inconclusive test results) and 50 patients were hospitalized (group II, 29 positive and 21 inconclusive test results). In group I, cardiac events (unstable angina and non-fatal infarction) occurred in the next 30 days of follow-up in 2 patients with inconclusive test results; no cardiac events occurred in patients with negative test results. In group II, unstable angina was diagnosed in 30 patients and 3 presented recurrent angina. There were no complications during exercise testing. In conclusion, early exercise testing is safe and useful in the stratification of patients seen in the emergency room for chest pain. Only patients with negative test results should be discharged early.

Characterization of cobalt pigments found in traditional Valencian ceramics by means of laser ablation-inductively coupled plasma mass spectrometry and portable X-ray fluorescence spectrometry

In this work, a comparison of the performances of laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) and portable X-ray fluorescence (XRF) spectrometry for the characterization of cobalt blue pigments used in the decoration of Valencian ceramics is presented. Qualitative data on the elemental composition of the blue pigments obtained using both techniques show a good agreement. Moreover, the results clearly illustrate that potters utilized different kinds of cobalt pigments in different historical periods. While both techniques seem suitable for the proposed task, they show different strengths and weaknesses. Portable X-ray fluorescence spectrometry is a cheaper and totally non-destructive technique, capable of providing fast and reliable results at the mgg(-1) level. LA-ICPMS, on the other hand, offers a much higher detection power and better spatial resolution, but its use results in some sample damage (sample consumption at the mug level), while it is a more expensive and non-portable technique.

Predictors of short-term outcome in acute chest pain without ST-segment elevation

BACKGROUND Management of acute chest pain in the emergency room constitutes a challenge. METHODS Seven hundred and one consecutive patients were evaluated by clinical history (chest pain score and risk factors), ECG, troponin I and early (<24 h) exercise testing in low risk patients (n=165). A composite end-point (recurrent unstable angina, acute myocardial infarction or cardiac death) was recorded during hospital stay or in ambulatory care settings for patients discharged after early exercise testing. RESULTS The end-point occurred in 122 patients (17%). Multivariate analysis identified the following predictors: chest pain score > or =11 points (OR=1.8, 2-2.8, 95% CI, P=0.007), age > or =68 (OR 1.6, 1.1-2.4 CI 95%, P=0.03), insulin-dependent diabetes mellitus (OR 1.9, 1.1-3.4 CI 95%, P=0.02), a history of coronary surgery (OR 3.3, 1.5-7.2 CI 95%, P=0.003), ST-segment depression (OR 1.9, 1.2-3.0 CI 95%, P=0.009) and troponin I elevation (OR 1.6, 1.1-2.5, CI 95%, P=0.05). ST-segment depression produced a high end-point increase (31 vs. 13%, P=0.0001). Troponin I elevation increased the risk in the subgroup without ST-segment depression (20 vs. 11%, P=0.006) but did not further modify the risk in the subgroup with ST depression (31 vs. 28%, ns). Nevertheless, the negative ECG and troponin I subgroup showed a non-negligible end-point rate (16% when pain score > or =11 or 7% when pain score <11, P=0.004). Finally, no patient with a negative exercise test presented events compared to 7% of those with a non-negative test (RR=2.5, 2.1-3.1 95% CI, P=0.01). CONCLUSIONS Emergency room evaluation of chest pain should not focus on a single parameter; on the contrary, the clinical history, ECG, troponin and early exercise testing must be globally analysed.

Factores pronósticos en la angina inestable con cambios dinámicos del electrocardiograma. Valor del fibrinógeno

Introduction and objectives. The prognosis of unstable angina varies between series depending on the inclusion criteria and management protocol used. The aim of this study was to analyze in-hospital events and their predictors in a homogeneous single-center series of patients with unstable angina. Material and methods. A total of 246 patients with the following inclusion criteria were studied: 1) resting anginal pain, 2) transient electrocardiographic changes during anginal pain, 3) normal CK-MB levels and 4) exclusion of postinfarction angina. All patients were treated with aspirin and enoxaparin (1 mg/kg/12 h). Coronary angiography was performed in the case of recurrent angina or ischemia in Bruce I-II stage during the predischarge effort stress test. The variables recorded were risk factors, history of ischemic heart disease, history of coronary surgery, ECG upon admission, and fibrinogen. Results. During the hospital stay the following events were recorded: 36% recurrent angina, 58% cardiac catheterization, and 5,7% major events (infarction or death). Multivariate analysis found recurrent angina to be more frequent in patients with a history of coronary bypass surgery (p = 0.004. OR = 22; CI 95%, 3-182), ST-segment changes (p = 0.01. OR = 4.7, CI 95%; 1.4-15.9) and higher fibrinogen (p = 0.002. OR = 1,4, CI 95%; 1.1-1.7). Fibrinogen was the only variable related to cardiac catheterization (p = 0,009. OR = 1.3. CI 95%, 1.1-1.6) and major events (p = 0.001. OR = 2.0. CI 95%, 1.4-3.1). Conclusions. 1) Unstable angina with electrocardiographic changes was associated to a high rate of in-hospital events. 2) Fibrinogen was related to any event, and previous by-pass surgery and ST changes were related to recurrent angina.

Free Radicals and Antioxidants in Physical Exercise

The beneficial effects of exercise are well documented. Indeed, it ameliorates diabetes mellitus, improves the plasma lipid profile, increases bone density and may help to lose weight. However, as stated in the old medical saying “the beneficial effects of exercise are lost with exhaustion”. It has been known for some time that exhaustive exercise causes muscle soreness, induces an elevation of cytosolic enzyme activities in blood plasma and may be harmful. In the last decade a considerable amount of information concerning production of free radicals in exhaustive exercise has been obtained. An international symposium took place in Valencia, Spain in 1993 and a book was published on the subject (Sen, Packer, and Hanninen, 1994). This subject has been reviewed by (Bendich, 1991; and Ji, 1995). In this chapter we will summarize the present state of the art on this subject. The reader will find more information in the aforementioned sources.

Symptomatic Partial Congenital Absence of the Pericardium Revealed Using Cardiac Magnetic Resonance

Congenital absence of the pericardium is a very uncommon finding, and its diagnosis poses a challenge because it is rarely suspected in daily clinical practice. Although in most cases it has a benign course, this congenital defect should be identified because of the associated risk of sudden death. We present a symptomatic case of partial congenital absence of the left pericardium suspected as the result of an abnormal response to exercise stress testing, and confirmed using cardiac magnetic resonance imaging. We review the current diagnostic tools and therapeutic indications of this rare anomaly.