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The recent developments of synchronized cardiac MRI are a unique opportunity for the radiology community to integrate cardiac imaging. This educational aticle aims to help radiologists and technicians to obtain cardiac planes comparable to those of cardiac ultrasound and gated SPECT. Of course, cardiac planes described herein for MRI also apply to multi-detector CT.

As people live longer, so cardiologists are having to manage coronary artery disease in progressively older patients with more severe coronary lesions. The authors tried to determine the feasibility and results of coronary angiography in a retrospective study of 65 patients (44 men and 21 women) over 75 years of age (range 75 to 84 years) with coronary artery disease (excluding valvular heart disease). The study period was 22 months. The commonest indication was unstable or invalidating angina resistant to medical therapy (42 of the 65 cases). Twenty-two patients underwent coronary angiography in the context of myocardial infarction complicated in 3 cases by septal rupture. With the exception of these 3 patients, two of whom underwent surgery, 39 of the 62 remaining patients were judged to be candidates for myocardial revascularisation (63%); 37 underwent a revascularisation procedure (60%), 20 by percutaneous transluminal coronary angioplasty and 17 by coronary bypass surgery. The primary success rate of angioplasty was 90% (18 out of 20). There were no deaths in this group. Two patients who were referred for surgery died, an operative mortality of 12% (2 out of 17). All patients were followed up: 56 out of the 65 were still alive at the time of enquiry, after an average period of 18 months. All surviving patients who were successfully revascularised (by angioplasty or surgery) were pauci- or asymptomatic. Although there is an increased mortality related to revascularisation of elderly patients, this would seem to be acceptable given the quality of the medium term clinical results.

The possibility of an intraventricular pressure gradient in patients with aortic stenosis is well known: this entity is associated with a high risk of postoperative complications. The authors carried out a Doppler echocardiographic study of flow in the left ventricle in 51 patients who had recently undergone valve replacement for severe aortic stenosis (valve area0.75 cm2). Before surgery, only one patient had significant acceleration of intraventricular systolic flow attaining 3.8 m/s (maximum pressure gradient of 60 mmHg). After surgery, maximum intraventricular systolic velocities of over 2.5 m/s with a typical end systolic peak were observed in 8 patients under basal conditions (gradients of 30 to 115 mmHg), and in 7 others after inhalation of amyl nitrite. Pulsed spectral and color Doppler flow mapping showed that the highest velocities were located at the mitral papillary muscle level. In addition, these patients had significant reduction in cavity size. Only one patient had systolic anterior motion of the anterior mitral leaflet with septal contact. Left ventricular dimensions were measured by TM echocardiography. High intraventricular velocities seemed to be significantly related to the smallest ventricular dimensions, the thickest ventricular walls and the smallest preoperative aortic valve surface area. The highest intraventricular pressure gradients-disappeared with betablocker therapy (4 cases), after correction of hypovolemia (1 case), after drainage of large pericardial effusions (2 cases) or spontaneously (1 case). This study confirms the relatively high prevalence of dynamic intraventricular gradients after surgical cure of aortic stenosis and the value of Doppler echocardiography for the avoidance of certain drugs (inotropic agents, vasodilators, diuretics), which could aggravate the hemodynamic abnormality.(ABSTRACT TRUNCATED AT 250 WORDS)

The authors report the case of radiofrequency ablation of atrioventricular conduction in a 5 months pregnant woman who had hypertrophic cardiomyopathy. The indication of this procedure was a poorly tolerated resistant supraventricular tachycardia with foetal distress. A dual-chamber rate-assisted pacemaker programmed in the VVIR mode was implanted during the same procedure normally, with normal delivery of a healthy child at 8 months' gestation.

It has been suggested that an algorithm of automatic adaptation of the AV delay to the instantaneous atrial rate be introduced into the program of DDD pacemakers to reproduce the physiological adaptation of the PR interval to effort, characterised by progressive shortening inversely linearly related to the heart rate. In order to evaluate the potential benefits in conditions of "standard" programming (basal AV delay the same for all patients: maximal frequency of 1/1 AV synchronisation uniformly limited to 120 bpm), a haemodynamic study was undertaken in 10 patients who had permanent DDD pacemakers implanted for advanced AV block. Measurements were taken during two standardized exercise stress tests (20 W/2 mn steps from an initial load of 20 W) performed in a random order, one with a fixed AV delay of 156 ms and the other with an "automatic AV delay" allowing linear reduction from a maximum value of 156 ms at rest to a minimum value of 84 ms at the maximum heart rate of 120 bpm. At the peak of exercise the "automatic AV delay" significantly affected 4 parameters: the paced ventricular rate (p = 0.008) and rate-pressure product (p = 0.005) which increased, pulmonary capillary pressure (p = 0.03) and cycle-to-cycle variability of systolic and diastolic blood pressures (p = 0.02p0.0001) which decreased. There was a tendency (NS) to slowing of the spontaneous atrial rate and to increase in cardiac output. This increase was significant in some patients and seemed to be due to a good relationship between the individual optimal value of the value basal AV delay measured by Doppler echocardiography and the value programmed in this study (156 ms).(ABSTRACT TRUNCATED AT 250 WORDS)

Doppler-echocardiography is playing an increasing role in cardiac pacing: 1) Before implantation, to determine any cardiac disease possibly accompanying the conduction disturbance, and the quality of atrial function in order to identify the appropriate indications for the type of pacing which will restore normal AV synchronism. Alongside morphometric data (size of atria, etc.), this analysis is based above all on the evaluation of LV filling flows and ejection, if necessary during provisional pacing in DRV mode. It is important to be aware of and prevent certain problems: 1st degree AV block with very long PR, high degree interatrial conduction disturbances, etc. 2) To evaluate the possible benefits of pacing in certain new indications, e.g. obstructive hypertrophic cardiomyopathy (measurement of intra-LV gradient in sinus rhythm and with DRV pacing with total ventricular capture). 3) After implantation, to optimise the programming of double-chamber pacemakers and in particular AV intervals (base-line AV interval with paced atrial cycle, AV interval with detected atrial cycle, hysteresis of AV interval corresponding to the difference between the two previous values, slope of automatic variation in AV interval during exercise, etc.). Individual programming of these parameters based upon analysis of transmitral and ejection flow rates, at rest and, if necessary, during exercise, enables the optimisation of cardiac function (which is above all useful in the presence of concomitant organic heart disease) while at the same time improving the electrophysiological behaviour of the pacemaker at high frequencies.

Male contraception apart from vasectomy and the condom is still in a virtually experimental stage. An acceptable male method must not interfere with sexual function and must meet the same demands for safety, simplicity, efficacy and reversibility as female methods. Condoms are the oldest and most effective reversible male method. Vasectomy is a simple and safe procedure, popular in some countries. Its biggest drawback is its uncertain reversibility even after successful reanastomosis. Hormonal approaches to male contraception are based on use of steroid or peptide compounds to inhibit production of the gonadotropins luteinizing hormone (LH) and follicle stimulating hormone (FSH) by the pituitary, resulting in azoospermia. The actual development of such methods has been confounded by imperfect knowledge of the hormonal mechanisms regulating spermatogenesis. The method requires 2 months to become effective because the process of human spermatogenesis is so lengthy. Rates of azoospermia greater than 70-80% have never been achieved. Among substances used, testosterone enanthate is unacceptable because of irregular efficacy and secondary effects inherent in the doses of androgens. Several progestins have been studied in combination with injectable, implanted, or percutaneous androgen therapy. Azoospermia is not usually achieved and secondary effects are significant. Medroxyprogesterone acetate has given more promising results in limited trials. Cyproterone acetate and danazol, a synthetic analog of 17 alpha ethinyl testosterone, are powerful but have significant side effects. The expectation that superanalogs to gonadotropin releasing hormone (GnRH) would provide a male hormonal method has thus far not been met. GnRH agonists have never yet produced a durable azoospermia in human males, even with continuous perfusion of elevated doses. It has recently been shown that the required androgen substitution interferes with achievement of azoospermia. GnRH antagonists appear more promising, but the androgen substitution poses a similar problem to that encountered with GnRH agonists. The first human trials are now underway. The hormonal approach may ultimately provide an interesting choice for individuals able to have regular spermograms, but does not appear feasible on a wide scale. A direct approach to male contraception at the level of the epididymis or testicles is theoretically interesting because of the rapidity of the effect. Gossypol, a phenolic compound extracted from cotton oil or seeds, provides extreme oligospermia in 99.9% of users, but the effect has been irreversible in a nonnegligible proportion of men using it for more than 2 years. Other compounds tested have been too toxic for clinical use. Immunological approaches pose major theoretical problems and all developments remain experimental. A better knowledge of the physiology of spermatogenesis and of the control of sperm movement will be required for development of a satisfactory male contraceptive method.

International audience; Que se joue-t-il dans le quotidien d'une ville comme Beyrouth où les traces de la guerre qui y a sévi pendant quinze ans s'offrent encore aujourd'hui, en de nombreux endroits, au regard de ses habitants? La description des usages de la mémoire à l'échelle d'un quartier détruit de la capitale permet d'approcher la construction des temporalités urbaines en lien avec la période des guerres libanaises (1975-1990). La ville, espace du quotidien et des pratiques ordinaires, constitue un support et un vecteur des expressions mémorielles. Dans la banalisation de la destruction ou dans la fondation de hauts lieux par des entreprises mémorielles militantes, la société citadine qualifie des traces de la guerre qui bien souvent symbolisent ce qui précisément fut un des enjeux de la guerre civile : la coexistence des communautés dans l'espace urbain. Pour autant, si l'objet mémoriel supposé de ces traces est la guerre, leur force évocatrice ne s'y limite pas. L'analyse de ce qui se joue autour des immeubles en ruines du quartier de Khandaq al-Ghamiq, ancien quartier mixte de Beyrouth, vise la compréhension de la construction des identifications collectives contemporaines. Les pratiques de transmission, d'héritages et les représentations dont ces immeubles sont l'objet révèlent la complexité des relations entre les souvenirs jugés « bénéfiques » et ce qui peut apparaître comme le négatif du travail de la mémoire, ses zones d'ombre et de déni de certains épisodes du passé. De ce fait, ce qui pouvait apparaître au premier abord comme une lacune liée aux conditions particulières de l'enquête devient, dans l'analyse, révélateur des tensions qui régissent la manière et le pouvoir de dire (ou non) la guerre.