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Un recours dirigé contre une décision juridictionnelle, qui, par hypothèse, a pour objet l’annulation – ou la réformation – de cette décision se fonde toujours sur un moyen pris de la méconnaissance d’un droit consacré par une norme, quelle que soit la valeur de cette norme, son origine, son contenu. Que fait-on lorsque le jugement est conforme à la norme ? Sa validité ne serait pas contestable. Quoique… Ne peut-on pas contester la norme ? Il y a là, il est vrai, une mise en abyme : la juridi...

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The increasing interest in "warm" aerobic cardioplegia requires a critical reevaluation of the systemic effects of the associated normothermic cardiopulmonary bypass (CPB). As activated neutrophils seem to be essential mediators of the inflammatory response to CPB via the cytotoxicity of the products that are released during their adhesion to endothelial cells, the authors undertook a study of the influence of temperature on the interaction between the neutrophils and the endothelium in 95 patients undergoing warm (31-33.5 degrees C, n = 49) and cold (26-27 degrees C, n = 46) CPB surgery. Blood sampling was performed before, during and after CPB. The following markers of neutrophil-endocardium interaction were analysed: complement activation (C3a), cytokine production (tumor necrosis factor alpha, interleukines 1, 6 and 8, and interleukin-1 receptor antagonist); endothelial expression of cytokine-dependent [intercellular adhesion molecule (ICAM)] and cytokine-independent (P-selectin) adhesion molecules (P-selectin); expression of cytokine molecules on the surface of polynuclear neutrophils (CD11a, CD11b, CD11c); and finally, endothelial adhesion and transendothelial migration of neutrophils (interleukin 8 and elastase). The results showed that, irrespective of temperature, CPB was associated with changes strongly suggestive of phenomena of transendothelial adhesion and migration. Moreover, normothermia increased the intensity of the inflammatory response as shown by increased cytokine production, earlier expression of neutrophil adhesion molecules and increased elastase production.

Infected median sternotomy often requires open wound management. A large thoracic defect usually results in subsequent exposure of heart, great vessels, aorto-coronary bypass grafting or vascular prosthesis. After thorough wound debridement, coverage with muscle transposition was carried out in a series of 167 cases observed over a period of 10 years. Transposition of both pectoralis major muscles on internal pedicles was performed in 75 cases. In 27 of these cases, internal mammary grafting did not preclude their use. Since 1986, intrathoracic transposition of the trapezius muscle has been our treatment of choice in 25 cases, most frequently combined with a double pectoralis major transposition. Rectus abdomini muscle flap was seldom used alone whereas latissimus dorsi was mainly used as a salvage flap. Muscle transposition provided effective heart and great vessel protection after acute hemorrhage in 18 cases. This series confirms that mortality and mean hospital stay have decreased dramatically since the routine use of muscle transposition.

Piwnica Fabrice. Les résistances à l'introduction du libéralisme en France. Le témoignage des mémoires des corporations en 1776. In: Revue d’histoire moderne et contemporaine, tome 40 N°1, Janvier-mars 1993. Comportements et sensibilités dans la France du XVIIIe siècle. pp. 30-48.

In an attempt to provide a consistent protection of cardiac allografts during the sequence of events inherent in transplantation procedures, we developed two preservation solutions of which one is used for initial arrest, storage and cardioplegia during graft implantation, whereas the other serves as initial reperfusate. The formulations of these solutions are closely interrelated and their design has integrated the basic principles of organ preservation with those of myocardium-specific metabolism. Based upon experimental studies in the isolated rat heart model, this integrated approach has yielded better functional recoveries than conventional preservation protocols.

Infected median sternotomy often requires wide debridement. A large thoracic defect usually results with subsequent exposition of heart, great vessels, aortocoronary bypass grafting, vascular prosthesis. Coverage with muscles transplantation was the standard procedure carried out in this series of 150 cases observed between 1983 and 1991. Details of technique are presented as well as a review of our reconstructive options. Rewarding results were observed even in the most challenging circumstances, suggesting that pursuing this aggressive approach was warranted.

Over the last few years there has been a renewal of interest in retrograde administration of cardioplegic solutions but this method has not been validated by a large scale clinical trial. From 1980 to 1989 our group used retrograde coronary sinus perfusion as the only means of administering cardioplegia in 500 consecutive patients undergoing isolated aortic valve replacement (AVR) (359 cases) or associated with another valvular or myocardial revascularization procedure (141 cases). Using this method, there were 31 hospital deaths (6.2%) of which 20 were of cardiac origin (4%). During the last 5 years, hospital mortality for isolated AVR decreased to 1.5%. With an incidence of low cardiac output of 12%, of arrhythmias and atrioventricular block of 7.4% and 1.2% respectively, and of myocardial infarction of 1.4%, this method of cardioplegia compares favourably with anterograde perfusion. There were only 3 traumatic lesions of the coronary sinus, all occurring at the beginning of the series and all of which were successfully repaired. Retrograde coronary sinus perfusion is therefore a safe and effective method of cardioplegia during aortic valve surgery: the cardioplegic solution is distributed uniformly in patients with coronary artery disease and therefore, this could become the technique of choice for myocardial protection in coronary artery or mixed coronary and valvular surgery.

The authors report two operated cases of floating left atrial thrombus. Both patients had severe mitral stenosis, atrial fibrillation and dilatation of the left atrium. In the first case, the patient had no anticoagulant therapy; in the second case, the observance of anticoagulant therapy was irregular. Neither patient complained of syncope. The diagnosis was made in both cases by two-dimensional echocardiography which, in addition to confirming the severe mitral stenosis, showed a round, free-floating intra-atrial mass, rebounding from wall to wall and repeatedly engaging itself into the mitral orifice. The risk of prolonged engagement of the thrombus in the mitral orifice, causing syncope or sudden death, justifies urgent surgery associating thrombectomy and treatment of mitral stenosis every time this problem is encountered.

A lethal case of acute respiratory distress syndrome of the adult following extracorporeal circulation for aorto-coronary bypass is reported. This case illustrates the two mechanisms currently thought to be responsible for this pathology: (1) the passage of blood over the synthetic fibres of the cardiopulmonary bypass machine activates the complement, and the systemic inflammatory reaction that ensues accounts for the increased permeability of the alveolar capillary membrane; (2) the haemodilution inherent in extracorporeal circulation explains the hypoproteinaemia usually observed at the end of the procedure; the resulting fall in capillary osmotic pressure upsets the equilibrium of pressures in the capillary vessels.

There is at this point a large number of experimental studies suggesting that oxygen free radicals play a major role in the pathogenesis of the myocardial lesions observed during the sequence ischemia-revascularization. Today, it is stressed upon the role of leucocytes as well as iron as major mediators in triggering and maintaining free radicals generating reactions which lead to a lipidic peroxidation of the membranes. It is probable, and anyway desirable, that these converging studies result, in the very near future, in the development of free radicals traps which are clinically usable. Such a development is still undissociable from the identification of specific markers of radicals lesions in the tissues, which is a mandatory condition for a serious evaluation of the procedures likely to bring under control the harmful effects of these unstable oxygen derivatives and therefore complete the arsenal of anti-ischemic treatments.

The object of this study was to establish whether the protective effects of a cardioplegic solution could be improved by ionic or pharmacological intervention aimed at reducing cellular Ca++ overload resulting from myocardial ischaemia. The experimental model was the isolated perfused working heart of the rat submitted to 60 or 120 minutes of hypothermic ischaemia (15 degrees C) followed by 30 minutes of reperfusion at 37 degrees C. The high energy phosphates were measured every 2,5 or 5 minutes by Phosphorus 31 (P31) nuclear magnetic resonance and correlated with haemodynamic data. Our results showed that the best metabolic (75,5 +/- 9,7 p. 100 preservation of ATP after 60 minutes ischaemia) and functional protection (91,8 +/- 4,7 p. 100 recovery of aortic output after 30 minutes reperfusion) was obtained with a solution with the following ionic properties: 1) high Mg++ concentration (13 mM); 2) low Ca++ concentration (0,25 mM); 3) high Na+ concentration (100 mM). The protective effects of this solution were further improved by the addition of a calcium blocking agent (nifedipine 0,2 micrograms/ml). This preserved 85,5 +/- 3,2 p. 100 of basal ATP values after 120 minutes of ischaemia and was associated with a 92,9 +/- 2,8 p. 100 recovery of aortic output at the end of reperfusion. We conclude that: 1) limitation of cellular Ca++ overload is one of the major objectives to be considered when making up cardioplegic solutions; 2) the use of P 31 nuclear magnetic resonance on the isolated working heart is the technique of choice for comparing methods of myocardial protection because it provides a non-invasive, sequential and simultaneous assessment of the parameters of metabolic and haemodynamic function.

A case is reported of subacute carciac failure during the course of a non-obstructive cardiomypathy in an adolescent. When the exacerbation of cardiac failure, which was accompanied by severe arrhythmias, failed to respond to medical treatment, the combination of a veno-arterial bypass and membrane oxygenator with diastolic counter-pressure from an intra-aortic balloon was tried with success. A reasonable remission was obtained by this means, but the young patient died 8 months later from cardiac failure which proved resistant to treatment.

The present study deals with a series of 40 reoperations in a group of 1279 patients undergoing mitral valve replacement. All reoperations were late following the immediate post-operative period, the earliest being 5 months after the primary operation. The factors which were analyzed are: causes of reoperation, the most frequent being paravalvular leaks and valve thrombosis, diagnostic methods, surgical techniques and results following reoperation.

A surgical operation with a "curative" aim has been performed on four patients with a lone ventricle. It consisted of a IA type in 3 cases and IC type in one. There were one operative death and three long-term survivals. The operation consisted essentially in: a delicate step of partition of the lone cavity and the treatment of the often combined, and sometimes complex, heart malformation. The trauma to the conduction pathways is one of the major dangers of this type of operation and should be avoided or decreased by the detection during operation of the His bundle. Operation should be indicated in badly tolerated forms. Stenosis of the infundibulo-pulmonary pathway interferes with the development of a hypertensive pulmonary arteriolitis, seems to be a favourable element for surgical correction. In the absence of such stenosis, one should perform a banding early enough or discuss the indication for an intracardiac operation in relation with the pulmonary artery resistance.

The aim of this study is to define the hemodynamic characteristics of this "clinical model" of acute cardiac failure observed after cardiac surgery carried out under extra-corporeal circulation, which constitutes the essential cause of "post-operative low cardiac output syndrome". The 193 patients in this study make up a representative sample of patients operated, treated and studied according to a homogeneous methodology for a period of 1 year. The clinical analysis of the post-operative circulatory condition, after exclusion of non cardiogenic syndromes, led to grouping the cases into 5 classes of circulatory change of increasing severity, each corresponding to a specific "therapeutic necessity". The hemodynamic results (intra-vascular pressures, oxymetry, cardiac output by "Cardio-Green" dilution method) are given for each of the five classes, thus defining the "hemodynamic profile" and the statistical reliability of the main objective parameters. This gives proof of the therapeutic indications for the main therapeutic procedures actually known, for which we prevent the hemodynamic effects noted for each of them. Thus, three "degrees of cardiac failure" are found: less severe (classes I and II) call for simple metabolic equilibration and possibly diuretics: the systolic work is above 160 gm/m2. Decompensated circulatory failure (classes III and IV) corresponds to a more important reduction in systolic work (9) 15 gm/m2, i.e. between 20 et 40 p. 100 of the basal value), and call for sympatho-mimetic cardiotonic agents: isoprenaline and/or dopamine. Below this value, in spite of medical treatment, the hemodynamic situation can still be sometimes reversible under circulatory assistance (diastolic counter pressure by means of an aortic balloon). Confronted with the clinical picture, the hemodynamic study enables the quantification of the circulatory change, and specification of the cardiogenic part and thus especially helps the carrying out of the treatment.

Fluorocarbons are synthetic compounds capable of dissolving large amounts of gases (O2, CO2, N2, CO). The current availability of stable O2- carrying emulsions delivering substantial volumes of this gas to perfused tissues makes it possible to extend the potential clinical use of perfluorochemicals. In cardiology, fluorocarbons have proven experimentally efficient during cardiopulmonary bypass as blood substitutes, in cardioplegic and reperfusion solutions and as agents designed to reduce the size of acute myocardial infarcts. However, a more thorough understanding of their long-term effects on cells is needed before their routine clinical use can be considered.

An 11 to 15 year follow up (mean 12.7 years) of 90 patients undergoing surgery for coarctation of the isthmus of the aorta is reported. There were 7 late deaths. Of the survivors 87% were normotensive (B.P. less than or equal to 160/100 mmHg) and 90% were asymptomatic and leading a normal life. Five cases-all with an aortic prosthesis-had to be reoperated for recurrent coarctation. These figures are comparable with those found in the literature. The best long-term results are obtained in patients who have the operation while young (less than 20 years), who have no associated abnormality, and whose coarctation can be treated by resection with direct anastamosis.

Tricuspid incompetence occuring in isolation is extremely rare, and had only been described under certain very particular conditions: trauma, septicaemia of genital origin, intravenous injection of narcotics. Idiopathic dilatation of the auricle of the right atrium is a disorder which has been described during the last fifteen years or so, and is recognised mainly because of the disorders of rhythm which it causes. These two cases demonstrate that, in the long-term, massive dilatation of the auricle can lead to tricuspid incompetence by dilating the ring, and require surgical intervention.

Refractory and recurrent ventricular tachycardias are a common cause of death after myocardial infarction. The occurrence of intraventricular re-entries can be prevented by a new surgical treatment based on encircling thermic exclusion. The Nd-YAG laser beam offers 2 major advantages over previous techniques: it acts rapidly with minimal myocardial damage and can even be used in patients with left ventricular dysfunction.

Nuclear magnetic resonance (NMR) is a non-invasive exploratory technique based on a principle radically different from those of radiography, radionuclide exploration and ultrasonography. Signals coming from atomic nuclei and reflecting their density and chemical/biochemical environment are collected, thus providing information of the physiological and pathological state of tissues. The technique has multiple applications, either practical (tomographic imaging of the brain, thyroid gland and liver) or in the field of research, e.g. investigating ischaemic myocardial areas and pathological fluid composition, measuring intracellular pH, diagnosing the nature of a tumour and, broadly speaking, understanding the biochemical changes associated with malignant degeneration.

Between October 1982 and May 1986, 12 patients were implanted with an automatic defibrillator AID-B; 7 had coronary artery disease, 2 had dilated cardiomyopathies and 3 had torsades de pointe with or without long QT intervals. Five patients had a thoracic approach with a left ventricular patch and implantation of a right atrial endocavitary electrode. Thereafter a subcostal approach was used with 2 patch electrodes. Two of the first 5 patients rejected the device, but this complication was not observed in the remaining 7 cases. The threshold of defibrillation was greater than 25 joules in 1 case out of 5 with a patch and endocavitary electrode. This threshold was less than 25 joules in all patients with 2 patch electrodes. The AID-B was triggered in less than 20 seconds. One patient died of pulmonary embolism 8 days after implantation; 2 others had a temporary aggravation of their arrhythmias. There were no cases of inappropriate activation of the AID-B device during follow up: 5 patients had no arrhythmia or defibrillation. The 6 others had 2 to 35 defibrillations with documented arrhythmias before or after defibrillation. One patient suffered a sudden death after exhaustion of the device which had functioned on two occasions but had not been replaced for economic reasons. The technique of implantation has been simplified, so limiting local complications. This device is reliable and represents an effective palliative treatment of sudden death due to ventricular arrhythmias.

Coarctations of the thoraco-abdominal aorta are rare malformations. Whilst determining the need for surgery, in general because of hypertension, raises few problems, the choice of surgery tactics gives rise to discussion. The choice must above all take into account the risks of visceral ischaemia, in particular affecting the spinal cord, the causes of which are at one and the same time technical (total aortic clamping, sacrifice of the intercostal arteries) and haemodynamic (blood pressure variations). Under such conditions, it would seem necessary to reject resection-suture. Discussion is thus limited to aortoplasty with a widening patch, which is suitable in particular for short stenoses of easy access and to by-pass from ascending aorta to abdominal aorta, electively more indicated in cases of extensive coarctation with severe periaortitis, though the long-term fate of such by-passes remains uncertain.