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Publications and source records attributed to M Toussaint.
This case report demonstrates that bilateral internal mammary angiography through a single right-radial approach is feasible and convenient. It avoids double-brachial or radial artery puncture, is adapted to the variable characteristics of right internal mammary artery origin, and may be considered when the femoral approach is contraindicated.
BACKGROUND: The Bard XT stent is a balloon expandable stent with a new design, consisting of discrete zigzag modules welded onto a flexible longitudinal spine. METHODS: To assess the safety and efficacy of this recently introduced coronary stent, we studied 81 patients (107 lesions) who underwent implantation of 108 such stents (66% elective). RESULTS: Primary success in stent delivery was 97.1% and angiographic success was achieved in all cases. Reference segment diameter was 2.69+/-1.4 mm and average lesion length 10.9 mm. Mean minimal luminal diameter before the procedure was 0.79+/-1.11 mm and increased to 2.55+/-1.09 mm after stenting. Diameter stenosis decreased from 76%+/-24% to 9%+/-12%. One Q wave and 1 non-Q-wave myocardial infarction occurred but no other significant complications were observed. At 1-month follow-up, angiographically documented subacute thrombosis occurred in 2 cases at days 1 and 3. Conclusions These preliminary data suggest that the Bard XT stent has a promising design for the safe and effective treatment of coronary lesions, even in the presence of high-risk clinical and unfavorable angiographic characteristics.
Coronary lumen changes after excimer laser coronary angioplasty, after adjunct percutaneous transluminal coronary angioplasty, and at 24 hours after intervention were assessed using quantitative coronary angiography. Lesions treated with this combined technique showed significant early deterioration within 24 hours.
To evaluate the mechanisms of lumen enlargement and the respective contributions of rotational coronary atherectomy (RA) and adjunctive percutaneous transluminal coronary balloon angioplasty (PTCA), serial measurements were recorded in 70 consecutive patients by quantitative coronary angiography before RA, after RA, after adjunctive PTCA, and 24 hours later. Minimal luminal diameter (MLD) increased from 0.85 +/- 0.31 mm to 1.42 +/- 0.27 mm (p < 0.001) after RA and to 2.20 +/- 0.46 mm (p < 0.001) after PTCA. Minimal luminal area (MLA) increased from 0.64 +/- 0.50 mm2 to 1.63 +/- 0.60 mm2 (p < 0.001) after RA and to 3.97 +/- 1.68 mm2 (p < 0.001) after PTCA. Both 24-hour MLD and MLA showed a trend toward reduced values (2.07 +/- 0.45 mm and 3.52 +/- 1.70 mm2, respectively) when compared with immediate results after PTCA. The absolute gains in MLD after RA and after PTCA were 0.56 +/- 0.24 mm and 0.79 +/- 0.38 mm, respectively (p < 0.01). The absolute gains in MLA after RA and after PTCA were 0.99 +/- 0.49 mm2 and 2.34 +/- 1.41 mm2, respectively (p < 0.001). The respective contributions of RA and PTCA are highly variable, but in general, balloon dilatation accounts for most of the gain in lumen area and therefore is not an adjunctive but a primary technique.
First- and second-night effects on the electroencephalogram (EEG) were investigated by means of polygraphic sleep recordings and all-night spectral analysis. Eighteen normal subjects were studied for three consecutive nights in a hospital sleep laboratory. Visual sleep scoring showed that there was a first-night effect in normal subjects similar to that reported previously [increased wakefulness; decreased total sleep time, sleep efficiency, and rapid eye movement (REM) sleep]. Spectral analysis of the sleep EEG revealed important changes, most of which occurred in REM sleep. Increased delta, theta, and beta1 power densities accompanied by decreased mean frequency were seen in REM sleep in the second night. On the basis of REM sleep deprivation results previously published, our data suggest that the second night could be affected by partial REM sleep deprivation that occurred in the first night. Delta and theta power density values decreased in the first non-rapid eye movement episode of nights 1 and 2; this could result from increased REM sleep pressure. The overall consistency of spectral data in the first and second night with REM sleep findings derived from visual scoring in the first night lends further support to this hypothesis. The sleep disturbance experienced during the first night in a sleep laboratory may be a useful and valid model of transient insomnia. Therefore, we conclude that data from all nights recorded should be included in assessing a subject's sleep.
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Large lumen guiding catheters (9.5 to 11 French) are currently required to perform directional atherectomy. These rigid guiding catheters require modifications of usual techniques for manipulation and can induce ostial trauma and peripheral vascular complications. A new type of 9 French guiding catheter (Vista Brite tip, Cordis, Miami, FL) with an inner diameter of 0.098 inch and capable of accomodating atherectomy catheters (SCA-EX) was evaluated. In this preliminary study, 31 consecutive patients were included. Primary success was obtained in 27 (87%); no ostial trauma and only two minor groin hematomas were observed. After exchange with a conventional 10F guiding catheter, because of poor back-up, two of the four failures were successfully treated by DCA. In conclusion, these new 9F guiding catheters provide a useful alternative to currently available guiding catheters for DCA. Nevertheless, new shapes with better back-up are necessary to improve the primary success rate.
Studies on extended data including 37 electroencephalographic (EEC) records of delta-sleep, each 10(3) s long (six subjects: up to seven nights per subject, comprising normal sleep, partial deprivation and recovery), confirmed earlier conclusions that rare episodes of low-dimensional dynamic self-organization, with life-times between 10 and 20 s, are present in stage 4 sleep. Particular care was taken of the Theiler correction which, in some delta-sleep signals, required the deletion of trajectory points covering nearly one pseudo-period. The percentage of segments showing an episode, i.e. the attractor probability, decreased with a change in sleep conditions either deprivation or recovery prior to the next deprivation. Repetition of deprivation over three nights resulted in an adaptation process, manifested by an increase in attractor probability. After the sharp decrease in probability observed when recovery was established prior to the next deprivation, and on return to normal conditions of sleep at 2200 hours, the probability was immediately close to that observed in normal baseline sleep conditions free of any interference. The observation of a definite effect of sleep deprivation and recovery upon the number of stage 4 attractors observed provides a line of approach to the physiological significance of the probability of such attractors.
In this paper, we compare and analyze the results from automatic analysis and visual scoring of nocturnal sleep recordings. The validation is based on a sleep recording set of 60 subjects (33 males and 27 females), consisting of three groups: 20 normal controls subjects, 20 depressed patients and 20 insomniac patients treated with a benzodiazepine. The inter-expert variability estimated from these 60 recordings (61,949 epochs) indicated an average agreement rate of 87.5% between two experts on the basis of 30-second epochs. The automatic scoring system, compared in the same way with one expert, achieved an average agreement rate of 82.3%, without expert supervision. By adding expert supervision for ambiguous and unknown epochs, detected by computation of an uncertainty index and unknown rejection, the automatic/expert agreement grew from 82.3% to 90%, with supervision over only 20% of the night. Bearing in mind the composition and the size of the test sample, the automated sleep staging system achieved a satisfactory performance level and may be considered a useful alternative to visual sleep stage scoring for large-scale investigations of human sleep.
The pharmaco-EEG profile and the effects on P300 and CNV of befloxatone, a new selective and reversible MAO-A inhibitor, were assessed in a randomized, double-blind, placebo-controlled, 4-way crossover study. Twelve healthy young male volunteers were administered single doses of 2.5, 10 and 20 mg befloxatone and placebo separated by a 1-week washout. The EEG data were recorded before and at least 6 h after drug administration, by means of 28 leads allowing topographical analysis of the results. MAO inhibition, subjective effects and safety variables were also investigated. Statistical analysis was performed by means of the SDT method. Befloxatone induced dose-related EEG changes which occurred rapidly, peaked between 0.5 and 2 h and lasted at least until 6 h after drug administration. The EEG changes were characterized by an increase in absolute and/or relative alpha power, mainly alpha 1, after the 3 doses and a theta power increase after 10 and 20 mg only. These changes occurred mainly over the centroparietotemporal areas. Concerning the event-related potential, P300 latency of the auditory evoked potentials did not change. The P300 and CNV mean topographic amplitudes were decreased, between 0.5 and 2 h, after the two lowest doses for the P300 and the 3 doses for the CNV. After administration of 2.5, 10 and 20 mg, MAO inhibitions was shown by respectively 38, 76 and 81% reduction in plasma free 3, 4-dihydroxyphenylglycol reached after 2-4 h. Such a pharmaco-EEG profile, occurring at doses inducing MAO-A inhibition, is similar to those already described with nonsedative antidepressants.
Stent deployment in a lesion with a large side branch is an example of the potential limitation of intracoronary stents, especially the Palmaz-Schatzª stent with its tubular slotted design. This case study describes a patient in whom a Palmaz-Schatz stent of excessive length covered the origin of a side branch (Òstent jailÓ). Thrombus developed in the jailed branch as well as in the main vessel, causing abrupt vessel closure and impending acute myocardial infarction within one hour after the procedure. This complication was successfully managed by emergency repeat angioplasty and implantation of a Micro Stentª on both branches, i.e. in the main vessel distal to the Palmaz-Schatz stent and in the side branch through the struts of the Palmaz-Schatz stent.
Venlafaxine, a member of a novel chemical class, phenethylamines, is a new antidepressant that inhibits neuronal uptake of serotonin, norepinephrine, and dopamine (in decreasing order of potency) at doses of 75 to 375 mg per day. Depression and antidepressant drugs are known to modify human sleep patterns. Our objective in this double-blind, placebo-controlled study was to assess the effects of venlafaxine on polysomnographic variables by comparing the effects of venlafaxine and placebo on sleep (hypnographic and all-night electroencephalographic [EEG] spectral analysis) and clinical measures (Hamilton Rating Scale for Depression [HAM-D], Montgomery-Asberg Depression Rating Scale [MADRS], and Clinical Global Impressions [CGI]) in inpatients with major depression (DSM-III-R). Following a 7- to 13-day placebo washout period, patients were randomly assigned to receive either placebo or venlafaxine (maximum dose 225 mg/day) for up to 29 days. Sleep evaluations took place at baseline (3 nights immediately before entering the double-blind phase), after 1 week of treatment, and after 1 month of treatment. Sleep stage parameters and all-night spectral parameters were first tested by analysis of variance for repeated measures and then, if indicated, by two-tailed Student t-test. The results on psychiatric rating scales showed improvement from baseline in both treatment groups at all time points, with improvement tending to be greater in the venlafaxine group. Venlafaxine induced a decrease of sleep continuity (decreased total sleep time and increased wake time), an important increase in the onset latency of rapid eye movement (REM) sleep, and a decrease in total REM sleep duration. All-night sleep EEG frequency structure was not modified significantly by venlafaxine treatment as compared with placebo. In conclusion, venlafaxine, despite its novel chemical structure, shows a sleep profile comparable with that of most classical antidepressants.
Earlier investigations have suggested that variables derived from quantified electroencephalographic (EEG) sleep analysis might predict good clinical response in an early phase of antidepressant treatment. In this report we evaluate the predictive value of all-night sleep EEG spectral analysis during the washout period before treatment. We compared the spectral EEG sleep profiles of major depressed inpatients divided into two groups according to an improvement > or = 50% on the Hamilton Rating Scale for Depression. Findings in this population demonstrate the presence of specific characteristics of the responder group compared with the nonresponder group. Delta band relative power was increased in the former group, while theta, alpha, and beta relative power were decreased. All the bands showed decrease in absolute power in the responder group. These results can be interpreted as enhanced sleep intensity in the responder group. All-night sleep EEG spectral variables are valid baseline markers of the functional differences between treatment responders and nonresponders and thus might permit prediction of clinical outcome.
The goal of the present study was to evaluate the first-night effect in psychiatric inpatients using large subject samples (n > 30) in order to obtain a good statistical evaluation. Thirty-two normal subjects and 94 psychiatric inpatients (38 depressives and 56 insomniacs) were studied for three consecutive nights in the hospital sleep laboratory. Our results showed clearly that there was a first-night effect in normal subjects, similar to that reported in previously published data, characterized by a longer rapid eye movement (REM) sleep latency (p < 0.05), increased wakefulness (p < 0.01) and total sleep time (p < 0.02) and a decreased sleep efficiency (p < 0.01). REM sleep latency and stage REM in the first third of the night were still altered in the second night. Both clinical groups had a less marked first-night effect than normal subjects, showing alterations only observed in REM sleep (p < 0.01) (decreased REM sleep, longer REM sleep latency, increased REM sleep gravity center). However, the first-night effect was more pronounced in insomniacs than in depressed patients. No statistical differences between the second and third nights' recordings were found in sleep parameters. It is suggested that first-night data should not be simply discarded but could be used in subsequent analyses.
Several new techniques have been developed to get round the limitations of conventional coronary angioplasty. Most entail ablation of the atheromatous plaques by mechanical (atherectomy) or photochemical (laser excimer) means, whilst others (stents) shore up the vascular walls. Their use with conventional coronary balloon angioplasty optimises the results of treatment of complex lesions. This report describes the authors' experience in 1,266 patients (1,668 lesions) treated between January 1992 to December 1993. The new techniques were used in 33% of patients and 30% of lesions (rotational) atherectomy: 20%; stents: 5%; directional atherectomy: 3%; laser excimer: 2%) because of the defavourable angiographic characteristics of the lesions (eccentricity, calcification, bifurcation, length, chronic total occlusion, thrombosis, ostial stenosis, ulceration, saphenous vein graft). The primary success rate was 91% in the whole group (94 to 97% for the patients treated by the new techniques). The global major complication rate was 1.7%. The multi-instrumental revascularization adjusted to the coronary lesions (MIRACLE) gives a high primary success rate in patients with coronary lesions difficult to treat by conventional angioplasty. Randomised trials will be necessary to determine the precise indications of each technique with respect to the morphological characteristics of each lesion.
One of the causes for percutaneous transluminal coronary angioplasty (PTCA) failure is the inability to cross the lesion with the balloon catheter after guidewire positioning. The Europass coronary angioplasty catheter is a monorail Duralyn balloon catheter developed to enhance lesion crossability and to overcome this limitation. This system was evaluated in 50 patients in which target lesions were chronic total coronary occlusions (12 cases) or stenoses that could not be reached or crossed by other new monorail balloon catheters. Overall procedural success was obtained in 49/50 patients (98%), using a single Europass balloon catheter in 46/50 patients (92%), with no in-hospital complications. Its low profile, small distal shaft, and excellent trackability allowed successful angioplasty in cases where other catheters failed. This balloon catheter represents a significant advance in angioplasty technology and can be considered as a first-choice device for a safe and expeditious single-operator procedure.
The project's aim is to develop a dedicated workstation in order to process multiple channels of electrophysiological signals in real-time during sleep. In ESPIS we are aiming to define both an architecture and an environment for EEG signal interpretation in medicine based on computer science gold standards (Unix, XWindow, Motif). Signal processing and pattern recognition analysis are provided by parallel processing on a specific developed acquisition architecture (DSP) based on transputers. The main result is a high performance prototype demonstrating signal interpretation during sleep which has already been tested in a medical environment. The overall specifications allow this biomedical device to be extended to other types of medical signals.
In order to study the short-term ecotoxicity of metals to the freshwater mussel Dreissena polymorpha, the effects of Cu, Zn and Cd on the filtration rate of this mussel were determined in laboratory experiments. Filtration rate was chosen as the endpoint, because it is a sensitive sublethal parameter compared to mortality and it is an important parameter given the ecological role D. polymorpha fulfills. The filtration rate was calculated from the decrease in algal concentration, fed to mussels in aquaria, containing different metal concentrations. The EC50 for Cu (41 microg litre(-1)) was lower than for Cd (388 microg litre(-1)) and Zn (1350 microg litre(-1)). The NOEC(accumulation) for the essential metal Zn was higher than for the essential metal Cu. Cadmium, a non-essential metal, was accumulated at all elevated water concentrations, so the NOEC(accumulation) was the concentration in the control water (<0.2 microg litre(-1)). All (no) effect concentrations found in this study were above the quality criteria set for metal concentrations in Dutch surface water, suggesting that the zebra mussel is sufficiently protected by these quality criteria.