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C Perdigão

Publications and source records attributed to C Perdigão.

At least 19 recordsLinked to original sources

Impairment of the erythrocyte membrane fluidity in survivors of acute myocardial infarction. A prospective study.

Erythrocytes have to constantly adapt themselves to the varying circulatory system shear stress forces and capillaries diameter. Membrane lipid and protein content have an important role in determining the erythrocyte shape and are main determinants of the membrane solid and fluid behaviour which enables the erythrocyte to respond to the outer environment modifications. Membrane fluidity is an inverse index of membrane microviscosity. The aim of the present work is to evaluate prospectively in three periods of time (discharge, after 6 months and one year later) in survivors of an acute myocardial infarction (AMI) the erythrocyte membrane fluidity (outer and inner bilayer) and establish a relation with the cardiovascular events or need of coronary revascularization during a two year clinical follow up. Sixty survivors of acute myocardial infarction were recruited during 1994-96 and were prospectively studied in three periods (discharge, 6 months and after one year), and were compared with a control group (n = 36). Membrane lipid fluidity was determined by means of fluorescence polarisation with two probes: 1,6-diphenyl-1,2,5-hexatriene (DPH) and 1,4-trimethylamine 6-phenyl hexa-1,3,5-triene (TMA-DPH), for the characterisation of the hydrophobic and external polar region, respectively. The hydrophobic region was more rigidified (p < 0.01) in the erythrocytes from AMI patients, in relation to the control group. During the time of the study there was a progressive erythrocyte membrane rigidification (DPH p < 0.001; TMA-DPH p < 0.001). We found no relation between erythrocyte membrane fluidity and the coronary risk factors, cardiovascular events or the need of coronary revascularization during the clinical follow-up. In conclusion, after the myocardial infarction erythrocyte membrane of AMI survivors becomes more rigid with time, which could contribute to the decreased erythrocyte deformability and the increased blood viscosity previously described in this group of patients.

Aged↗

[Rationale for the pharmacologic treatment of cardiovascular diseases].

In what concerns the appropriate usage of drugs in the treatment of cardiovascular diseases, this paper provides a set of concepts and guidelines to aid the clinician in the choice of drug, the appropriate dose, the form of administration and the assessment of results. Therefore, the concepts of pharmacokinetics and pharmacodynamics which condition the administration regimen are also presented, as well as the notions of bioavailability, halflife and clearance in the light of the theory of the two compartments, quoting examples in the various pharmacologic groups currently used in cardiology. The main forms of administration and the respective indications are analysed and the concepts of tolerance, hypersensitivity and intolerance to a drug are also discussed. The importance of the major clinical trials in the assessment of the effects of drugs is supported, which consubstantiates the clinical decision based on scientific evidence. The notions of the efficacy and benefit of a treatment are presented, with examples of some recent clinical trials. The paper ends with a reference to the drug surveillance and cost-benefit studies.

Biological Availability↗

[A challenge].

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Diagnosis↗

[Medical instruction].

A study is made of medical education based on the Flenex Reform. The new paths indicated by the Edinburgh Declaration, combining three great models: teaching based on the analysis and solution of problems, the SPICES model and integrated teaching, are presented. Some considerations are made on how the changes declared for the last decade of the century should be implemented, quoting the report from the Interministerial Commission for the Revision of Medical Education.

Education, Medical↗

[The role of the vascular endothelium and vasospasm in different coronary syndromes. A common physiopathological base for distinct entities?].

A literature review on the endothelial functions and endothelial dysfunction/lesion, as well as the atherosclerosis role in this process is performed. The several physiological explanations of both acute and chronic coronary syndromes are also reviewed, with particular emphasis to the recent studies on vasospasm mechanisms and its role in the physiopathogeny of variant angina and syndrome X. The role of the endothelial dysfunction/lesion as a common physiopathological basis to all coronary syndromes, is discussed.

Angina Pectoris, Variant↗

[Formation of left ventricular thrombus in acute myocardial infarction: significance of the determination of fibrinogen, of products of fibrinogen degradation, and of plasminogen].

OBJECTIVE: To evaluate the significance of the fibrinogen, the plasminogen and the fibrinogen degradation products levels as marks of left intraventricular thrombosis (LIVT) in acute myocardial infarction (AMI). METHODS: 219 consecutive patients of AMI admitted in a Coronary Care Unit of an University Hospital, were prospectively studied. All protocols included a clinical evaluation, an M-mode and 2D echocardiographic study and blood samples, at day 1, 3, 7 and at hospital discharge. In the intraventricular thrombus evaluation just the 4 Asinger grade was considered. In the laboratory evaluation we used: the Clauss chronometric method for the fibrinogen, the colorimetric method for the plasminogen and the agglutination in plaque for the FDP. The patients with ECO in the 2 or 3 Asinger grades and those in which ECO and laboratory study were not performed in the same day, were excluded. 101 patients remained on the study, and they were divided in two groups: 53 patients with LIVT and 48 patients without it. RESULTS: In both groups the fibrinogen raised along the first six days of the AMI, however in the group with LIVT this level didn't raise as high as in the group without LIVT (p < 0.001). In the FDP evaluation two peaks were found, one at 48 hours and another on the 6 th day, but there were no differences between the two groups. The plasminogen values raised along the first week of AMI, in a similar way in both groups. CONCLUSIONS: a) Fibrinogen levels raises in AMI, but this elevation is significantly smaller in the group with LIVT, which suggests fibrinogen consume in fibrin formation of the thrombus. b) FDP and plasminogen levels raise along the first week of AMI, but in a similar way in the two groups. c) None of these parameters permitted to individualize patients with thrombus formation.

Aged↗

[Coronary atherosclerosis in acute myocardial infarct. Anatomic profile of diverse causes of death].

OBJECTIVE: to study the degree of coronary obstruction by atherosclerotic plaques in a population dying with acute myocardial infarction. We defined subgroups by the degree of the obstructive lesion and compared the severity and distribution of coronary atherosclerotic lesions in different groups according to cause. STUDY DESIGN: systematic prospective study in patients dying in the acute phase of myocardial infarction in a University Hospital Coronary Unit during a four years period. POPULATION AND METHODS: we studied 193 patients corresponding 77% of the patients dead in the same period. 24 patients were excluded by technical reasons related to the preparation of necropsic material. The clinical protocol included 64 parameters and were considered the following causes of death: left ventricular failure (shock or acute pulmonary edema), left ventricular free wall rupture, interventricular septum rupture, primary asystole, pulmonary embolism and ventricular fibrillation. To study of the heart we performed the transverse slices technic after fixation; to study the epicardial coronary arteries we isolated the coronaries after fixation and made 5 mm transverse slices. The slices were macroscopic and microscopic evaluated for the degree of coronary obstruction in every 5 mm segment. We classified the degree of coronary obstruction in five grades: less than or equal to 25%; greater than 25% e less than or equal to 50%; greater than 50% e less than or equal to 75%; greater than 75% e less than 100%; and total obstruction. RESULTS: the degree of coronary obstruction in each epicardial segment were: Right ostium--grade I = 21%, grade II = 46%, grade III = 26%, grade IV = 7%, grade V = 0; Right coronary--grade I = 5%, grade II = 10%, grade III = 19%, grade IV = 28%, grade V = 38%; Left ostium--grade I = 27%, grade II = 50%, grade III = 19%, grade IV = 4%, grade V = 0; Left main--grade I = 16%, grade II = 43%, grade III = 28%, grade IV = 10%, grade V = 2%; Anterior descendent--grade I = 1%, grade II = 5%, grade III = 11%, grade IV = 34%, grade V = 49%; Left circumflex--grade I = 2%, grade II = 14%, grade III = 22%, grade IV = 40%, grade V = 22%. The number of coronary arteries with more than 75% obstruction for each group of one, two or three vessel disease were: 1 vessel--41 cases; 2 vessels--56 cases; 3 vessels--68 cases. The number of vessels with more than 75% obstruction for each cause of death were: Wall rupture--1 vessel = 20, 2 vessels = 18, 3 vessels = 11; Septum rupture--1 vessel = 0, 2 vessels = 2, 3 vessels = 2; Shock--1 vessel = 12, 2 vessels = 21, 3 vessels = 30; Acute pulmonary edema--1 vessel = 1, 2 vessels = 9, 3 vessels = 7; Asystole--1 vessel = 4, 2 vessels = 1, 3 vessels = 8; Pulmonary embolism--1 vessel = 2, 2 vessels = 5, 3 vessels = 8; Ventricular fibrillation--1 vessel = 2, 2 vessels = 0, 3 vessels = 2. CONCLUSION: in most patients dying with acute myocardial infarction, the coronary atherosclerotic lesions were present in two or three epicardial coronary arteries. The left anterior descendent artery was the more frequent artery with major lesion (greater than 75%). Major atherosclerotic lesion in just one vessel were more frequent in patients dying by cardiac rupture.

Autopsy↗

[Clinical case and review of the subject. Prognosis in acute myocardial infarction].

Aiming to discuss the value of the prognostic indices in the acute myocardial infarction (AMI), we present two cases of AMI, where the predictable prognosis at 48 hours of the onset of symptoms is informed by the outcome of each case. In the first one, a patient in cardiogenic shock had a good evolution because he suffered a biventricular infarction that responsed well to hydric overcharge. The other case, a Killip classe I infarction, was complicated by a late left ventricular free wall rupture. We discuss the several aspects of each case, and finally we do a critical aproach of the most common prognostic indices (Killip and Kimbal classes, Peel prognostic groups and Norris prognostic groups).

Heart Rupture, Post-Infarction↗

[Intraventricular thrombi in acute myocardial infarct. The Iberian Multicenter Study. Presentation of the study protocol and various preliminary results].

OBJECTIVE: To evaluate the incidence of left intraventricular thrombosis and systemic embolism after acute myocardial infarction, as well as to determine the risk factors of each one of them. To study the morphologic aspects of the thrombus and its relation with systemic embolism. CONCEPTION AND POPULATION: 1505 consecutive patients with acute myocardial infarction from six Iberian Hospital Coronary Care Units--five from Spain and one from Portugal--were studied. All protocols included a clinical evaluation and a M-mode and 2D echocardiographic study at days 1, 3, 7 at hospital discharge, as well as at months 1, 3, 6, 12, and 24 of the follow-up. In the intraventricular thrombus evaluation just the III and IV Asinger grades were considered. RESULTS: From the total studied patients an echocardiographic study of good quality for thrombus evaluation was found in 1360, and 305 (22.3%) of these had a left ventricular thrombus. In anterior infarctions the incidence of thrombus was 39.9%, and in the other localizations was 11.2%. In what concerns the thrombus morphologic aspects, we found a small thrombus (less than 4 cm2) in 71% of the cases, and a big one (greater than or equal to 4 cm2) in 29%; the shape was laminar in 53.6%, protuberant in 41.7% and pediculated in 4.6%; the outline was smooth in 56.7% and irregular in 43.3%; the echodensity was considered homogeneous in 60.1% heterogeneous in 37.6% and cavitated in 3.3%. Of the several parameters evaluated the following were correlated with left intraventricular thrombosis: anterior localization of the infarction, left ventricular failure, ventricular aneurysm, post infarction angina, bundle branche block and no thrombolytic therapy. The incidence of systemic embolism in a mean follow-up of 290 days was 3.96%, being maximum in the first month (3.4%), but an embolic episode still occurred in the following months in 3.02% of the cases. Systemic embolism correlated with left ventricular thrombus, the pediculated shape and the big size of it, as well as with the oldest patients. CONCLUSIONS: A high incidence of left intraventricular thrombosis after acute myocardial infarction correspond to a low incidence of systemic embolism. Some parameters correlated with intraventricular thrombus or with embolism, what allowed us to consider them as risk factors of these clinical entities.

Age Factors↗

[A case of rupture of the left ventricle free wall with papillary muscle dysfunction following acute myocardial infarction, operated on successfully].

The authors present a case of left ventricular free wall rupture post acute myocardial infarction, associated with mitral papillary posterior muscle necrosis, operated by infartectomy and mitral valvular protesis replacement. They refer the various complications occurred during the hospital staying, and discuss its medical and surgical approach. The patient was discharged alive and six months after the infarction keeps a moderate activity.

Female↗