Emotional and behavioral problems in adolescents and young adults with food allergy.

BACKGROUND: Adolescents with food allergy have poorer psychosocial outcomes compared with their nonallergic counterparts; however, few studies have prospectively examined the mental health of adolescents and young adults in this vulnerable population. Our objectives were to estimate the prevalence of emotional and behavioral problems in an epidemiological sample of adolescents and young adults with food allergy; determine whether food allergy is associated with adolescent and maternal reports of such problems; and examine the patterns of change in emotional and behavioral problems from adolescence to young adulthood among individuals with and without food allergy. METHODS: Data came from 1303 participants at 14 and 21 years of age in the Mater University Study of Pregnancy. Emotional and behavioral problems were measured using self- and maternal-reported symptoms of depression, anxiety, attention/deficit hyperactivity disorder (ADHD), oppositional defiant disorder, and conduct disorder. RESULTS: Maternal, but not self-reports suggested that emotional and behavioral problems were higher among adolescents with food allergy. Food allergy was associated with increased odds of elevated levels of maternal-reported symptoms of depression [OR = 4.50 (1.83, 11.07)], anxiety [OR = 2.68 (1.12, 6.44)], and ADHD [OR = 3.14 (1.07, 9.19)] in adolescence. Food allergy was also associated with depressive symptoms that persisted from adolescence to young adulthood [OR = 2.05 (1.04, 4.03)]. CONCLUSIONS: Emotional and behavioral problems, particularly symptoms of depression, anxiety, and ADHD, are common among adolescents with food allergy in the general population and, in the case of elevated levels of depressive symptoms, persist into young adulthood. Healthcare professionals should seek adolescent and parental perspectives when assessing emotional and behavioral problems and monitor mental health during the transition to adulthood.

Manganese-Enhanced MRI in Patients with Multiple Sclerosis.

BACKGROUND AND PURPOSE: Cellular uptake of the manganese ion, when administered as a contrast agent for MR imaging, can noninvasively highlight cellular activity and disease processes in both animals and humans. The purpose of this study was to explore the enhancement profile of manganese in patients with multiple sclerosis. MATERIALS AND METHODS: Mangafodipir is a manganese chelate that was clinically approved for MR imaging of liver lesions. We present a case series of 6 adults with multiple sclerosis who were scanned at baseline with gadolinium, then injected with mangafodipir, and followed at variable time points thereafter. RESULTS: Fourteen new lesions formed during or shortly before the study, of which 10 demonstrated manganese enhancement of varying intensity, timing, and spatial pattern. One gadolinium-enhancing extra-axial mass, presumably a meningioma, also demonstrated enhancement with manganese. Most interesting, manganese enhancement was detected in lesions that formed in the days after mangafodipir injection, and this enhancement persisted for several weeks, consistent with contrast coming from intracellular uptake of manganese. Some lesions demonstrated a diffuse pattern of manganese enhancement in an area larger than that of both gadolinium enhancement and T2-FLAIR signal abnormality. CONCLUSIONS: This work demonstrates the first use of a manganese-based contrast agent to enhance MS lesions on MR imaging. Multiple sclerosis lesions were enhanced with a temporal and spatial profile distinct from that of gadolinium. Further experiments are necessary to uncover the mechanism of manganese contrast enhancement as well as cell-specific uptake.

Quantification of cardiomyocyte contraction based on image correlation analysis.

Quantification of cardiomyocyte contraction is usually obtained by measuring globally cell shortening from the displacement of cell extremities. We developed a correlation-based optical flow method, which correlates the whole-cell temporal pattern with a precise quantification of the intracellular strain wave at the sarcomeres level. A two-dimensional image correlation analysis of cardiomyocytes phase-contrast images was developed to extract local cell deformations from videomicroscopy time-lapse sequences. Test images, synthesized from known intensity displacement fields, were first used to validate the method. Intracellular strain fields were then computed from videomicroscopy time-lapse sequences of single adult and neonatal cardiomyocytes. The propagation of the sarcomeres contraction-relaxation wave during cell contraction has been successfully quantified. The time-varying patterns of intracellular displacement were obtained accurately, even when cardiomyocyte bending occurred in pace with contraction. Interestingly, the characterization of the successive 2D displacement fields show a direct quantification of the variation with time of intracellular strains anywhere in the cell. The proposed method enables a quantitative analysis of cardiomyocyte contraction without requiring wave tracking with the use of fluorescent calcium probes. Thus, our algorithmic approach provides a fast and efficient tool for analyzing the correlation between global cell dynamical behavior and mechanosensitive intracellular processes.

Theoretical analysis of the adaptive contractile behaviour of a single cardiomyocyte cultured on elastic substrates with varying stiffness.

In vivo, cardiomyocytes interact with surrounding extracellular matrix while performing periodically a contractile behaviour, which is the main determinant of heart performance. As extracellular substrates with easily tunable stiffness properties, polyacrylamide gels (PAGs) provide valuable flexible media for studying in vitro the dynamical behaviour of cardiomyocytes responding to stiffness variations of their surrounding environment. We propose in this paper an original mechano-chemical model of the cardiac cell contraction that sheds light on the adaptive response of cardiomyocytes evidenced recently in the experiments of Qin et al. [2007. Dynamical stress characterization and energy evaluation of single cardiac myocyte actuating on flexible substrate. Biochem. Biophys. Res. Commun. 360, 352-356]. The model links the amplitude of the extracellular PAGs strain fields to the spatio-temporal variation of the intracellular stresses in every part of the cell during the sarcomeres contraction-relaxation. In a continuum mechanics framework, we derived a unified description of the sarcomere-length dependence of intracellular active stress and of its control by anisotropic calcium diffusion and autocatalytic calcium release from the sarcoplasmic reticulum. Taking benefit of our previous work on the characterization of mechanical properties of PAGs with varying stiffness, we were thus able to evaluate the active intracellular stress exerted by the cardiomyocyte on flexible PAGs with different and known Young's moduli. Interestingly, we were able to explain the intriguing increase of maximal cellular stress observed experimentally when substrate stiffness is increased. By providing an evaluation of the whole-field cell stresses and strains, this integrative approach of cardiomyocyte contraction provides a reliable basis for further analysis of additional cooperativity and mechanotransduction mechanisms involved in cell contractility regulation, notably in physiological and pathological situations where modifications of cardiac performance are linked to varied stiffness of the cardiomyocytes environment.

Morphological and biomechanical aspects of vulnerable coronary plaque.

Vulnerable plaque morphology has been described by gross pathology and intravascular ultrasound, but morphological criteria cannot fully explain vulnerability, which involves four distinct factors: 1) inflammatory and biological processes; 2) geometry; 3) composition; and 4) hemodynamic stress. These last three aspects underlie the biomechanical study of vulnerable plaque. By virtue of the nature of their evolution, atherosclerotic plaques tend to be excentric, and this is a crucial morphological feature, causing circumferential stress to peak in very specific juxta-luminal locations, where it can exceed the rupture threshold of collagen, the basic constituent of arterial architecture. The lipido-necrotic core covered by a fibrous cap, formed in young plaques, is another morphological feature, which, can also increase and concentrate circumference stress in the juxta-luminal fibrous cap. The larger the lipid core, the thinner the fibrous cap and the greater is the stress. There are also inflammatory processes in such areas, which tend to reduce cap thickness. Ruptures occur when this thickness falls below 65 microns. Heart rate, blood pressure and pulse pressure are all biomechanical factors affecting vulnerable arterial walls, increasing circumferential stress and material fatigue. Vulnerable plaques are almost always associated with positive arterial remodeling. Numerical simulation has shown such so-called compensatory remodeling to be exclusively due to the healthy arc stretching in vulnerable plaques. Positive remodeling is optimal when the healthy arc is around 170 degrees, which keeps the lumen area relatively stable as long as the plaque does not exceed 40% to 50%. This mechanism does not apply to concentric plaques. In conclusion, the mechanism of vulnerable plaque rupture is highly complex and multifactorial. This complexity more or less precludes prediction in individual cases: we are in the realms of chaos theory and acute sensitivity to initial conditions. The greatest caution is therefore required in any attempt to predict rupture from diagnostic imagery, which provides only morphological data on plaque's nature.

In vivo detection of cortical plaques by MR imaging in patients with multiple sclerosis.

BACKGROUND AND PURPOSE: In vivo detection of cortical lesions in patients with multiple sclerosis (MS) by MR imaging is hampered by several factors. Among them is the low contrast between small cortical lesions and surrounding cortical gray matter offered by present techniques. METHODS: T1-weighted 3D spoiled gradient-recalled-echo (SPGR) volumes and 2D fluid-attenuated inversion recovery (FLAIR) sequences of 22 patients with MS who had 12 monthly brain MR imaging examinations at 1.5T, using a quadrature head coil, were retrospectively analyzed. These serial studies were coregistered and averaged to generate a single high signal-to-noise ratio (SNR) mean image, which was used to identify cortical lesions. The means of 12 FLAIRs and SPGRs from 14 age- and sex-matched healthy volunteers were analyzed as well. RESULTS: No cortical lesions were found on images of healthy subjects. Eighty-six cortical lesions were identified in 13 (59.1%) patients, predominantly in the frontal lobe (73.3%); 23.3% of cortical lesions lay entirely in the cortex, whereas the remaining lesions invaded the white matter underneath. CONCLUSION: Averaging multiple SPGRs created a single high SNR volume, allowing identification of cortical lesions. Because data were obtained monthly for 1 year, the average image does not account for transient lesion activity. However, for cortical lesions that remained stable during this time, the findings are valid in demonstrating the importance of high SNR images for detecting cortical brain abnormalities in MS.

Acute thrombotic obstruction with disc valve prostheses: diagnostic considerations and fibrinolytic treatment.

Twenty-six patients presenting with 28 instances of massive acute thrombotic obstruction of a prosthetic valve (16 mitral, 12 aortic) were treated with fibrinolytic agents. In 15 cases the patient presented with acute pulmonary edema and low cardiac output, in 10 with congestive heart failure and embolism and in 3 with peripheral embolism only. The diagnosis of thrombotic obstruction was made by echocardiography or cineradiography, in patients in whom the disc was immobile or barely moving; cineangiography was necessary in only four patients. The fibrinolytic agents administered were streptokinase, 2,000,000 U for 10 hours (14 cases), urokinase, 4,500 U/kg per h for 12 hours (7 cases), or the two agents successively (7 cases). Fibrinolysis was entirely successful in 19 patients: 18 are alive and well without surgical intervention after follow-up of 6 to 64 months and 1 patient had surgical revision after fibrinolysis. In two patients, fibrinolytic treatment was apparently successful but obstruction recurred 4 and 19 months later, respectively, and the patients were again treated by fibrinolysis. In two patients complete failure of fibrinolytic treatment led to emergency surgery, and in three patients improvement was incomplete and death occurred shortly after treatment. No hemorrhagic complications were observed, but there were five cases of embolism during the fibrinolytic treatment. Fibrinolytic treatment would seem to be an attractive, nonsurgical alternative for the thrombosis of a valve prosthesis but, because of the risk of embolism with possible permanent damage, its use should be reserved for critically ill patients who are too sick to undergo immediate surgery.

Non-linear elastic properties of the lingual and facial tissues assessed by indentation technique. Application to the biomechanics of speech production.

This paper aims at characterizing the mechanical behavior of two human anatomical structures, namely the tongue and the cheek. For this, an indentation experiment was provided, by measuring the mechanical response of tongue and cheek tissues removed from the fresh cadaver of a 74 year old woman. Non-linear relationships were observed between the force applied to the tissues and the corresponding displacements. To infer the mechanical constitutive laws from these measurements, a finite element (FE) analysis was provided. This analysis aimed at simulating the indentation experiment. An optimization process was used to determine the FE constitutive laws that provided the non-linear force/displacements observed during the indentation experiments. The tongue constitutive law was used for simulations provided by a 3D FE biomechanical model of the human tongue. This dynamical model was designed to study speech production. Given a set of tongue muscular commands, which levels correspond to the force classically measured during speech production, the FE model successfully simulated the main tongue movements observed during speech data.

Tortuosity of coronary bifurcation as a potential local risk factor for atherosclerosis: CFD steady state study based on in vivo dynamic CT measurements.

The purpose of the present study was to determine whether in vivo bifurcation geometric factors would permit prediction of the risk of atherosclerosis. It is worldwide accepted that low or oscillatory wall shear stress (WSS) is a robust hemodynamic factor in the development of atherosclerotic plaque and has a strong correlation with the local site of plaque deposition. However, it still remains unclear how coronary bifurcation geometries are correlated with such hemodynamic forces. Computational fluid dynamics simulations were performed on left main (LM) coronary bifurcation geometries derived from CT of eight patients without significant atherosclerosis. WSS amplitudes were accurately quantified at two high risk zones of atherosclerosis, namely at proximal left anterior descending artery (LAD) and at proximal left circumflex artery (LCx), and also at three high WSS concentration sites near the bifurcation. Statistical analysis was used to highlight relationships between WSS amplitudes calculated at these five zones of interest and various geometric factors. The tortuosity index of the LM-LAD segment appears to be an emergent geometric factor in determining the low WSS amplitude at proximal LAD. Strong correlations were found between the high WSS amplitudes calculated at the endothelial regions close to the flow divider. This study not only demonstrated that CT imaging studies of local risk factor for atherosclerosis could be clinically performed, but also showed that tortuosity of LM-LAD coronary branch could be used as a surrogate marker for the onset of atherosclerosis.

Quantitative analysis of left-ventricular function using gated single photon emission tomography.

We describe a quantitative method that measures segmental motion of the left ventricle, using tomographic slices obtained by gated single photon emission tomography (GSPECT). These slices contain the major axis of the left ventricle and are presumed to show wall motion directed towards a center of contraction. Values of parameters describing segmental wall motion in GSPECT were obtained from 61 patients, who received a left cardiac catheterization 1 hr later. These values were compared with results of similar calculations applied to data from contrast ventriculography. We conclude that GSPECT allows a detailed and quantitative, noninvasive study of wall motion of all left ventricular segments, with high inter- and intraobserver reproducibility.

In-vivo prediction of human coronary plaque rupture location using intravascular ultrasound and the finite element method.

BACKGROUND: Spontaneous rupture of atherosclerotic plaques is known to be involved in the mechanism leading to acute coronary syndromes. Means to detect plaques prone to rupture and predict rupture location would then be very valuable for clinical diagnosis. DESIGN: In this study, finite element (FE) analysis based on intravascular ultrasound (IVUS) images of atherosclerotic arteries was used to predict in-vivo plaque rupture locations. In four patients with coronary artery diseases, IVUS images were recorded before and after balloon angioplasty. Pre-angioplasty images were recorded after injection of ATP. This caused a brief drop of arterial blood pressure down to values of about 20 mmHg, and thus allowed the recording of the unloaded configurations of arteries used to initiate FE analysis. Plaque rupture was triggered by balloon inflation (coronary angioplasty). FE simulations were performed under physiological loading conditions. Stress distributions within the plaque and the arterial wall were determined. The corresponding stress maps are presented. RESULTS: Circumferential tensile peak stress areas were compared with plaque rupture locations on postangioplasty IVUS images. They were found to coincide in all four studied cases. CONCLUSION: Our results agreed with those reported in previous studies based on ex-vivo postnecropsic data and showed the feasibility of in-vivo prediction of atherosclerotic plaque rupture location.

Global left ventricular function and regional wall motion in pure mitral stenosis.

Global left ventricular function (LVF) and segmental wall motion of the left ventricle are registered in 113 patients presenting a pure mitral stenosis (MS) and in a control group of 50 individuals. The segmental wall motion is measured on the end-diastolic-end-systolic frames of the left ventricle, obtained from right anterior oblique (RAO) monoplane cineangiography. Measurement of the segmental wall shortening is performed using the Stanford method. Group 1 includes 68 patients (60% of the total number of patients studied). These patients show no pathological contraction abnormality. In this group, the global LVF is not different from the control group. Group 2 includes 45 patients (40% of the total) for whom contraction abnormalities are present: anterior hypokinesis in 20% of the cases (anterior area mean shortening (AAS) = 18 +/- 8%; p less than 0.001 vs. group 1 and control group), and posterior hypokinesis in 20% of the cases (posterior area mean shortening (PAS) = 9.8 +/- 5.8%, p less than 0.001 vs. group 1 and control group). In this group, global LVF is impaired; ejection fraction (EF) = 0.57 +/- 0.1% (p less than 0.001 vs. group 1); velocity of circumferential fiber shortening (VCF) = 1 +/- 0.3 circ/s (p less than 0.001 vs. group 1); enddiastolic pressure (EDP) = 11 +/- 5 mmHg (p less than 0.01 vs. group 1). Segmental contraction abnormalities appear to be the main factor involved in the global LVF impairment. Segmental wall motion abnormalities could be related to subvalvular fibrosis, or LV filling difficulties, or principally, to a possible interplay between the right and the left ventricles.

Quantitative frame by frame analysis of regional contraction and lengthening on left ventricular cineangiograms: application to the study of normal left ventricles and left ventricles with mitral valve prolapse.

This work attempted to study the segmental wall motion on left ventriculograms, in terms of segmental shortening, velocity of segmental shortening, and temporal sequences of various events in systole as well as in diastole. The ability of such a method to characterize patterns of normal regional wall motion and to detect mild abnormalities such as isolated asynchronisms, was tested on two groups of patients. Group I included 25 patients presenting evidence of a normal left ventricle (LV) after left heart catheterization. Group II consisted of 21 patients suffering from an isolated pure idiopathic mitral valve prolapse (MVP), with no mitral insufficiency and with an unaffected global LV function. In all patients left ventriculography was filmed in the right anterior oblique view at a rate of 50 frames/s. For each patient a cycle was chosen, distant from any premature beat, with acceptably contrasted outlines, and a quantitative frame by frame study of the motion of 10 segments was performed using a semiautomated method derived from the Stanford method. In the control group (Group I), analysis of the segmental motion by means of this method demonstrates a mild nonuniformity of the normal wall motion. This is principally marked by a stronger and faster contraction in anterolateral segments (segments 7, 8, 9) and by a shorter duration of the contraction in this region. In contrast the MVP group (Group II), exhibited a frank asynergy of the anterolateral region occurring from end systole to early diastole.(ABSTRACT TRUNCATED AT 250 WORDS)

Theoretical analysis of the effects of a radial activation wave and twisting motion on the mechanics of the left ventricle.

The mechanical effects resulting from the normal transmural delay of electrical depolarization of the myocardium are investigated. An activation sequence having a finite radial propagation velocity is introduced into the equations of ventricular mechanics. The resulting system of coupled integral equations is solved using a perturbation method based on the small ratio of transmural propagation time to cardiac period. Numerical calculations are performed using cavity pressure and volume waveforms characteristic of the canine left ventricle (LV), for both simultaneous and delayed activation of fiber layers. The results show that a finite transmural electrical propagation velocity tends to: (i) equalize the transmural distribution of sarcomere length during systole; (ii) equalize the transmural distribution of fiber external work/vol; and (iii) insignificantly affect myocardial tissue pressure. Calculations are also performed to investigate the mechanical effects resulting from the application of an externally applied moment that prevents LV torsion. Those results are highly dependent on the transmural distribution of sarcomere length in the stress-free reference state (unloaded diastole). When we assume a uniform distribution, then normal torsion acting with normal activation delay tends to: (i) increase the magnitude of fiber strain in the subendocardium and decrease it in the subepicardium; (ii) equalize the transmural distribution of fiber external work/vol; and (iii) lower myocardial tissue pressure. The normally occurring transmural delay of activation tends to lessen endocardial O2 demand, while the normally occurring torsion further lessens that demand and improves O2 supply.

Theoretical models in mechanics of the left ventricle.

Different rheological concepts and theoretical studies have been recently presented using models of myocardial mechanics. Complex analysis of the mechanical behavior of the left ventricular wall have been developed in order to estimate the local stresses and deformations that occur during the heart cycle as well as the ventricular stroke volume and pressure. Theoretical models have taken into account non-linear and viscoelastic passive properties of the myocardium tissue, when subjected to large deformations, through given strain energy functions or stress-strain relations. Different prolate spheroid geometries have been considered for such thick shell cardiac structure. During the active state of the contraction, the rheological behavior of the fibers has been described using different muscle models and relationships between fiber tension and strain, and activation degree. A forthcoming approach for bridging the gap between the knowledge of the muscle fiber microrheological properties and the study of the mechanical behavior of the entire ventricle, consists in including anisotropic and inhomogeneous effects through fiber direction field.

A modelized distribution of actomyosin interactions in the vertebrate cardiac muscle.

Preliminary assumption of this model is that interactions between actin and myosin presupposes an exact three-dimensional geometrical correspondence between sites, due to the very short time constants present under physiological conditions. Only small and controlled torsions of the actin filaments are accepted. The model uses geometrical information concerning orientations and dimensions of myosin crossbridges and actin monomeres to modelize the distribution of their inter-actions. An orientation map of actin sites in the cross-section perpendicular to the filament axis is proposed, adapted to the specific filament array of vertebrate muscle. Orientation of myosin crossbridges follows Luther's rules. According to the model, any interaction between actin and myosin implies the superimposition of their respective cross-sectional planes. The axial length of actin monomere is 55 A; the distance between two crossbridges along the myosin filament axis is 143 A. The following properties are derived: 1) The shortening step of the sliding actin filament must be a multiple of 11 A (highest common factor). Taking into account the staggered disposition of the two actin strands and the presence of two heads for each cross-bridge, the most probable value for this shortening step is equal to 99 A. A specific scheme is proposed to describe the shortening process. The behavior of the modelized crossbridge does not need any elastic structure--2) Planes situated at 715 A (lowest common multiple) of actin and myosin coinciding planes are also in coincidence. In a hemi-sarcomere the maximal number of these planes, referred to as simultaneously activable planes, is 10 (20 if both myosin heads are considered). The proportion of interactions authorized by the site orientations is 1/12. In the model, the concept of randomly recruited crossbridges is replaced by a discretized recruitment, based on geometrical properties at an ultrastructural level. The proposed distribution is homogeneous: it can be extended radially in the sarcomere and authorizes the actin filament sliding in the whole physiological range under the control of a dual activation function, reproducing Ca++ temporal and spatial distribution.

[Effects of injectable calcium blockers on cardiac function and relaxation in left ventricular hypertrophy]. / Effets des calcium-bloqueurs injectables sur la fonction cardiaque et la relaxation dans les hypertrophies du ventricule gauche.

Nineteen patients with left ventricular hypertrophy were given intravenous calcium antagonists: 9 patients received intravenous verapamil (VPM IV) and 10 patients diltiazem (DTZ) by intracoronary and then intravenous injection. Systemic and pulmonary resistances, cardiac output, left ventricular and aortic pressures, isometric contractility, isometric relaxation and left ventricular compliance were studied in sinus rhythm, during atrial and then ventricular pacing at 120/min and finally after tachycardia before and after administration of calcium antagonists. Left ventriculography in the 30 degrees RAO projection in sinus rhythm was performed before and after injection of the calcium antagonists to study the variations in the end diastolic volume, mass and mass-volume ratio. Finally, frame by frame numerisation of the ventriculographies during systole and diastole helped evaluate variations in amplitude, time and velocity of fibre shortening or lengthening. The administration of the calcium antagonists did not have any significant effect on heart rate (-2.8 +/- 10 p. 100, NS) or indices of isometric contractility (delta Vmax + 4 +/- 43 p. 100, NS). Significant falls in systemic and pulmonary resistances (-15 +/- 23 p. 100, p less than 0.05 and - 26 +/- 32 p. 100, p less than 0.05, respectively) and an increase in systolic index (+ 15.5 p. 100 +/- 12 p. 100, p less than 0.01) were observed. The improvement in left ventricular ejection was independent of the variation in resistances but was closely related to variations of parameters of relaxation. The effects on volumic compliance and filling velocities were also closely related to variations in relaxation (p less than 0.05 and p less than 0.01). Calcium antagonists protected left ventricular ejection during supraventricular tachycardia and prevented the changes in left ventricular relaxation observed during arrhythmias and after tachycardia.(ABSTRACT TRUNCATED AT 250 WORDS)

[Hemodynamic effects of a new positive inotropic agent (AR-L 115 BS) in ischemic and nonischemic myocardiopathies]. / Effets hémodynamiques d'un nouvel agent inotrope positif (l'AR-L 115 BS) dans les myocardopathies ischemiques et non ischémiques.

AR-L 115 BS is an imidazo-pyridine derivative with a positive inotropic action associated with peripheral and coronary vasodilatory properties. The effects of intravenous administration (a bolus of 0,45 mg/kg/min) were studied in 19 patients in functional class III of the NYHA classification in the absence of any previous drug therapy. Twelve patients had a primary myocardiopathy and the other 7 had coronary artery disease with akinetic anterior walls. A Swan-Ganz thermodilution catheter and a Millar microtransducer were used to measure pressures (pulmonary artery, left ventricular, aorta) and cardiac output under basal conditions and then every 2 minutes during intravenous administration of AR-L 115 BS. Left ventriculography in the 30 degrees RAO plane was performed under basal conditions and at the end of the investigation to measure volumes, ejection fraction, volumic compliance and segmental wall motion by the Stanford method. A stable concentration of circulating AR-L 115 BS was obtained (1 500 ng/ml). The positive inotropic action of the drug was responsible for a significant increase of all ejectional indices (cardiac and systolic index X 24 p. 100, p less than 0.01; ejection fraction +14 p. 100, p less than 0.01), of all indices of isometric contractility (dP/dt max +25 p. 100, velocity of contractile elements +35 p. 100, V max +30 p. 100 (p less than 0.01) and of the velocity of circumferential fibre shortening (+65 p. 100, p less than 0.001). All segmental shortening was improved.(ABSTRACT TRUNCATED AT 250 WORDS)

[Comparative effects of intracoronary fibrinolysis and conventional treatment of myocardial infarction]. / Effets comparés de la fibrinolyse intracoronaire et du traitement conventionnel dans l'infarctus du myocarde.

57 patients with a complete coronary thrombosis were treated by intracoronary fibrinolysis during the first 6 hours of inaugural myocardial infarction. The artery was revascularised in 37 cases (65 p. 100). Eleven patients had isolated stenosis of the left anterior descending artery and 16 patients isolated stenosis of the right coronary artery. These patients were compared with 27 other patients admitted between the 6th and 18th hours of primary myocardial infarction treated conventionally, in whom coronary angiography performed between the 14th and 21st day after infarction showed isolated left anterior descending disease in 14 cases (9 thromboses and 5 stenoses) and isolated right coronary disease in 13 cases (7 thromboses and 6 stenoses). The haemodynamic data and heart rates were identical in both groups during control coronary angiography between the 14th and the 21st days. Global left ventricular function and regional wall motion were studied by 30 degrees right anterior oblique ventriculography using the Stanford method before fibrinolysis in the first group and at the end of the 3rd week in both groups. In LAD, repermeabilisation by fibrinolysis, significant improvements were observed in ejection fraction (EF p. 100 = 42 +/- 9 vs 50.6 +/- 14 p. 100, p less than 0.05); fractional shortening of the hypokinetic segment (FS p. 100 = 4.5 +/- 4.6 vs 12.4 +/- 8.8 p. 100, p less than 0.001), and in the number of hypokinetic or akinetic segments (6.0 +/- 1.1 vs 4.2 +/- 2.1, p less than 0.05). Segmental and global left ventricular function was much poorer in the group treated conventionally at the 21st day (EF p. 100 = 44 +/- 11 p. 100, p less than 0.05; FS p.t100 = 5.8 +/- 9.7 p.t100, p less than 0.05; number of diseased segments: 6.0 +/- 1.4, p less than 0.01). On the other hand, the improvement was less marked in patients with inferior wall infarction; the results in the two groups were comparable.

[Refractory unstable angina. Emergency treatment by coronary artery angioplasty under aortic counterpulsion]. / Angor instable rebelle. Traitement d'urgence par angioplastie coronaire sous contrepulsion aortique.

We report our experience of 15 transluminal coronary angioplasties performed in an emergency in 13 patients (mean age 67 +/- 8 years) with refractory unstable angina. The procedures were conducted under diastolic counterpulsation effected by means of an intra-aortic balloon. The angina was of the threatening infarction type on 11 occasions and of the threatening extended infarction on 4 occasions. Electrocardiographic abnormalities were recorded in the anterior (11 cases) or in the inferior (4 cases) territory. Three patients had a very alarming haemodynamic status, with acute pulmonary oedema in two and cardiogenic shock in one. After intra-aortic counterpulsation was installed and the clinical signs were stabilized, coronaro-ventriculography was performed, leading to a decision of immediate angioplasty since age, underlying diseases, myocardial function and diffused lesions made most of the patients unsuitable for surgery. In multiple vessel patients electric and angiographic data were used to locate the tight stenosis (92% in all cases) responsible for the acute coronary ischaemia. The stenosis was found to affect the anterior interventricular artery in 9 cases, the circumflex artery in 2 cases, the right coronary artery in 2 cases and a saphenous shunt on the anterior interventricular artery in 2 cases. Immediate arteriographic and clinical success was obtained in 12 out of 15 cases (80%); there were 3 failures with 2 transmural infarctions. Later on, 2 patients underwent aorto-coronary bypass and 1 died of myocardial failure and pulmonary superinfection 3 weeks after the procedure. Ten of our 13 patients were stabilized and were discharged under medical treatment.(ABSTRACT TRUNCATED AT 250 WORDS)