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Background: As cognitive impairment in multiple sclerosis (MS) is a frequent and disabling symptom, it is particularly important to identify treatments that have proven efficacy in this aspect of the disease. Several disease-modifying therapies for MS have been evaluated and shown to have a potential effect on cognition and its neurobiological correlates, but to date there is very little data on Teriflunomide (TRF). The aim of this study is to explore the influence of TRF on comprehensive cognitive function and its MRI correlations (global and focal brain volume) in relapsing-remitting multiple sclerosis (RRMS) after two years of therapy., Methods: Twenty-four patients with RRMS were evaluated at baseline and after two years of treatment with BCcogSEP, a French translation of the Brief Repeatable Battery (BRB-N) including 3 additional tests. We explored the performance evolution for each test and correlation with MRI data for all patients. We also differentiated MS patients with and without cognitive impairment., Results: After two years of treatment, an improvement is observed at the Selective Reminding Test for mean number of words (p = 0.044), learning (p = 0.018), and delayed recall (p = 0.002) and at GoNoGo task (p = 0.022). At MRI, the corpus callosum volume variation correlates positively with SRT total recall test (p = 0,047). Intergoup analysis shows that the evolution of group performance differs only for the SRT total recall test. The comparison of patients with or without cognitive impairment showed a clear difference in white matter substance volume (p = 0,003) and in the Percentage Brain Volume Change (p = 0,016)., Conclusion: Results suggest that TRF treatment in RRMS has a positive effect in cognitive function, and specifically on long term verbal memory and inhibition. Neuroimaging data suggest a link between cognition and global and focal white matter volume, particularly in the corpus callosum which is involved in anatomical disconnection syndrome and therefore brain plasticity capacities., Competing Interests: Declaration of competing interest None., (Copyright © 2024. Published by Elsevier B.V.)

Throughout the world, anthropogenic pressure on natural ecosystems is intensifying, notably through urbanisation, economic development, and tourism. Coral reefs have become exposed to stressors related to tourism. To reveal the impact of human activities on fish communities, we used COVID-19-related social restrictions in 2021. In French Polynesia, from February to December 2021, there was a series of restrictions on local activities and international tourism. We assessed the response of fish populations in terms of changes in the species richness and density of fish in the lagoon of Bora-Bora (French Polynesia). We selected sites with varying human pressures-some dedicated to tourism activities, others affected by boat traffic, and control sites with little human presence. Underwater visual surveys demonstrated that fish density and richness differed spatially and temporally. They were lowest on sites affected by boat traffic regardless of pandemic-related restrictions, and when activities were authorised; they were highest during lockdowns. Adult fish density increased threefold on sites usually affected by boat traffic during lockdowns and increased 2.7-fold on eco-tourism sites during international travel bans. Human activities are major drivers of fish density and species richness spatially across the lagoon of Bora-Bora but also temporally across pandemic-related restrictions, with dynamic responses to different restrictions. These results highlight the opportunity provided by pauses in human activities to assess their impact on the environment and confirm the need for sustainable lagoon management in Bora-Bora and similar coral reef settings affected by tourism and boat traffic., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

During the COVID-19 pandemic, the reduced exports and imports as well as the lack of activity due to the interruption in the international tourism economy seriously impacted food security in many Pacific Islands. People often returned to natural resources to provide for themselves, their families, or to generate income. On Bora-Bora Island, the major tourist destination in French Polynesia, roadside sales are widespread. Our study analyses the impact of the COVID-19 pandemic on roadside sales activities through a census of roadside stalls on the five Bora-Bora districts conducted before (January and February 2020), during (from March 2020 to October 2021) and after (from November to December 2021) health-related activity and travel restrictions. Our results showed that the marketing system for local products (fruits, vegetables, cooked meals, and fish) increased in the form of roadside sales during the COVID-19 in two of the five districts of Bora-Bora. Roadside selling would be an alternative system for providing food to the population at Bora-Bora during a global crisis and that could reveal itself sustainable after this pandemic., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Minier et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

During the first COVID-19 lockdown in 2020, levels of coastal activities such as subsistence fishing and marine tourism declined rapidly throughout French Polynesia. Here, we examined whether the reduction in coastal use led to changes in fish density around the island of Moorea. Two natural coastal marine habitats (bare sand and mangrove) and one type of man-made coastal structure (embankment) were monitored on the west coast of the island before and after the first COVID-19 lockdown. At the end of the lockdown (May 2020), significantly higher apparent densities of juvenile and adult fish, including many harvested species, were recorded compared to levels documented in 2019 at the same period (April 2019). Fish densities subsequently declined as coastal activities recovered; however, 2 months after the end of the lockdown (July 2020), densities were still higher than they were in July 2019 with significant family-specific variation across habitats. This study highlights that short-term reductions in human activity can have a positive impact on coastal fish communities and may encourage future management policy that minimizes human impacts on coastline habitats., Supplementary Information: The online version contains supplementary material available at 10.1007/s10113-022-02011-0., Competing Interests: Conflict of interestThe authors declare no competing interests., (© The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2022, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Background: Severe combined immunodeficiency (SCID) comprises rare inherited disorders of immunity that require definitive treatment through hematopoietic cell transplantation (HCT) or gene therapy for survival. Despite successes of allogeneic HCT, many SCID patients experience incomplete immune reconstitution, persistent T-cell lymphopenia, and poor long-term outcomes., Objective: We hypothesized that CD4 + T-cell lymphopenia could be associated with a state of T-cell exhaustion in previously transplanted SCID patients., Methods: We analyzed markers of exhaustion in blood samples from 61 SCID patients at a median of 10.4 years after HCT., Results: Compared to post-HCT SCID patients with normal CD4 + T-cell counts, those with poor T-cell reconstitution showed lower frequency of naive CD45RA + /CCR7 + T cells, recent thymic emigrants, and TCR excision circles. They also had a restricted TCR repertoire, increased expression of inhibitory receptors (PD-1, 2B4, CD160, BTLA, CTLA-4), and increased activation markers (HLA-DR, perforin) on their total and naive CD8 + T cells, suggesting T-cell exhaustion and aberrant activation, respectively. The exhaustion score of CD8 + T cells was inversely correlated with CD4 + T-cell count, recent thymic emigrants, TCR excision circles, and TCR diversity. Exhaustion scores were higher among recipients of unconditioned HCT, especially when further in time from HCT. Patients with fewer CD4 + T cells showed a transcriptional signature of exhaustion., Conclusions: Recipients of unconditioned HCT for SCID may develop late post-HCT T-cell exhaustion as a result of diminished production of T-lineage cells. Elevated expression of inhibitory receptors on their T cells may be a biomarker of poor long-term T-cell reconstitution., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Fish development and acclimation to environmental conditions are strongly mediated by the hormonal endocrine system. In environments contaminated by anthropogenic stressors, hormonal pathway alterations can be detrimental for growth, survival, fitness, and at a larger scale for population maintenance. In the context of increasingly contaminated marine environments worldwide, numerous laboratory studies have confirmed the effect of one or a combination of pollutants on fish hormonal systems. However, this has not been confirmed in situ. In this review, we explore the body of knowledge related to the influence of anthropogenic stressors disrupting fish endocrine systems, recent advances (focusing on thyroid hormones and stress hormones such as cortisol), and potential research perspectives. Through this review, we highlight how harbours can be used as "in situ laboratories" given the variety of anthropogenic stressors (such as plastic, chemical, sound, light pollution, and invasive species) that can be simultaneously investigated in harbours over long periods of time., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The COVID-19 pandemic led to a global lockdown in mid-2020, leading to a rapid decline in international travel and tourism. In French Polynesia, marine-based tourism activities ceased in March 2020 with the suspension of international flights (i.e., 45 days - between 20th March and 04 th May 2020), slowly restarting between May-July as domestic and international visitors returned. The impacts of this rapid change in human activity at reef tourism sites on associated reef fishes was examined at Bora-Bora Island through underwater surveys of five control and nine eco-tourism sites. Our results showed that fish density significantly increased from March to May (i.e., the overall density of fishes increased by 143% and harvested species by 215%), but returned to pre-lockdown levels by August 2020. At the usually busy eco-tourism sites, fish diversity, notably of piscivores, omnivores, and benthic feeders, was higher in the absence of tourists. The impact observed is almost certainly related to short term changes in fish behavior, as any density fluctuations at the population level are unlikely to have happened over such a short time frame. Overall, these findings highlight the influence of human activities on fish communities and underline the need for further research to evaluate the environmental impacts of eco-tourism., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

How vocal organisms share acoustic space has primarily received attention in terrestrial environments. Comparable studies in marine environments, however, remain rare. By recording sounds on a coral reef in French Polynesia for 48 h and 24 h, this study provides first insights on how different sound types are distributed within the acoustic space and may create acoustic niches optimizing acoustic communication within a highly diverse community containing numerous soniferous fish species. Day-time was dominated by two to six sound types, while recordings performed at night revealed a more diverse vocal community made of up to nineteen sound types. Calling activity was distributed over time allowing each sound type to dominate the soundscape sequentially. Additionally, differences in the acoustic features of sounds occurring during the same period were observed. Such partitioning in time and acoustic spaces would reduce potential overlaps of sounds produced by vocal species living in sympatry in coral reefs.

Dory, the animated surgeonfish created by the Pixar Animation studios, famously suffered from short-term memory loss leading to many adventures. In reality, many fishes have excellent cognitive abilities and are able to learn and retain important information such as the identity of predators. However, if and how cognition can be affected by anthropogenically altered oceanic conditions is poorly understood. Here, we examine the effect of a widely used pesticide, chlorpyrifos, on the retention of acquired predator recognition in post-larval stage of the surgeonfish Acanthurus triostegus. Through associative learning, post-larvae of A. triostegus were first observed to forage significantly less in the presence of conspecific alarm cues and alarm cues associated to a predator's odor. The retention of this anti-predator behavior was estimated to last between 2 and 5 days in the absence of pesticide. However, environmentally-relevant concentrations of chlorpyrifos (1 μg.L -1 ) induced the loss of this acquired predator recognition. This reduced ability to recognize learned predators is discussed as it may lead to more vulnerable fish communities in coastal areas subjected to organophosphate pesticide pollution., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Encheliophis chardewalli was described from a single cleared and stained specimen. Twelve years later, additional specimens were found in the lagoon of Moorea (French Polynesia) in association with their host, the sea cucumber Actinopyga mauritiana. These fish were used to consolidate the species diagnosis, to validate species status and to record sound production. This species is remarkable because of its ability to penetrate inside the cloaca of sea cucumbers having anal teeth and the fact this species is largely unknown despite it lives in lagoons in 1m depth. Encheliophis chardewalli produced three sound types: long regular calls made of trains of numerous pulses, short irregular calls characterized by a constant lowering of its pulse period and short regular call (or knock) made of 3 to 6 pulses. Comparison with other sympatric Carapini supports a large and distinct repertoire. Morphological characteristics could be the result of reduced body size allowing to penetrate inside a new host, thus avoiding competition and conflict with other larger sympatric Carapini species., (© 2018 Wiley Periodicals, Inc.)

Understanding the relationship between coral reef condition and recruitment potential is vital for the development of effective management strategies that maintain coral cover and biodiversity. Coral larvae (planulae) have been shown to use certain sensory cues to orient towards settlement habitats (e.g. the odour of live crustose coralline algae - CCA). However, the influence of auditory cues on coral recruitment, and any effect of anthropogenic noise on this process, remain largely unknown. Here, we determined the effect of protected reef (MPA), exploited reef (non-MPA) soundscapes, and a source of anthropogenic noise (boat) on the habitat preference for live CCA over dead CCA in the planula of two common Indo-Pacific coral species (Pocillopora damicornis and Acropora cytherea). Soundscapes from protected reefs significantly increased the phonotaxis of planulae of both species towards live CCA, especially when compared to boat noise. Boat noise playback prevented this preferential selection of live CCA as a settlement substrate. These results suggest that sources of anthropogenic noise such as motor boat can disrupt the settlement behaviours of coral planulae. Acoustic cues should be accounted for when developing management strategies aimed at maximizing larval recruitment to coral reefs.

Acoustic recording has been recognized as a valuable tool for non-intrusive monitoring of the marine environment, complementing traditional visual surveys. Acoustic surveys conducted on coral ecosystems have so far been restricted to barrier reefs and to shallow depths (10-30 m). Since they may provide refuge for coral reef organisms, the monitoring of outer reef slopes and describing of the soundscapes of deeper environment could provide insights into the characteristics of different biotopes of coral ecosystems. In this study, the acoustic features of four different habitats, with different topographies and substrates, located at different depths from 10 to 100 m, were recorded during day-time on the outer reef slope of the north Coast of Moorea Island (French Polynesia). Barrier reefs appeared to be the noisiest habitats whereas the average sound levels at other habitats decreased with their distance from the reef and with increasing depth. However, sound levels were higher than expected by propagation models, supporting that these habitats possess their own sound sources. While reef sounds are known to attract marine larvae, sounds from deeper habitats may then also have a non-negligible attractive potential, coming into play before the reef itself., Competing Interests: The authors declare there are no competing interests.

Lateralization, i.e. the preferential use of one side of the body, may convey fitness benefits for organisms within rapidly-changing environments, by optimizing separate and parallel processing of different information between the two brain hemispheres. In coral reef-fishes, the movement of larvae from planktonic to reef environments (recruitment) represents a major life-history transition. This transition requires larvae to rapidly identify and respond to sensory cues to select a suitable habitat that facilitates survival and growth. This 'recruitment' is critical for population persistence and resilience. In aquarium experiments, larval Acanthurus triostegus preferentially used their right-eye to investigate a variety of visual stimuli. Despite this, when held in in situ cages with predators, those larvae that previously favored their left-eye exhibited higher survival. These results support the "brain's right-hemisphere" theory, which predicts that the right-eye (i.e. left-hemisphere) is used to categorize stimuli while the left-eye (i.e. right-hemisphere) is used to inspect novel items and initiate rapid behavioral-responses. While these experiments confirm that being highly lateralized is ecologically advantageous, exposure to chlorpyrifos, a pesticide often inadvertently added to coral-reef waters, impaired visual-lateralization. This suggests that chemical pollutants could impair the brain function of larval fishes during a critical life-history transition, potentially impacting recruitment success.

For marine fishes with a bipartite life cycle, pelagic larval dispersal can shape the distribution, connectivity, composition and resilience of adult populations. Numerous studies of larval dispersal, and associated settlement and recruitment processes, have examined the relationship between population connectivity and oceanographic features. However, relatively little is known about spatial and temporal variation in the abundance of larvae settling among different reefs and the extent to which the species assemblage of larvae settling at one location is reflective of the assemblage in neighbouring areas. Here, using crest nets, which provide a non-selective measure of the total abundance and assemblage of larvae settling to a reef (i.e. larval supply), we collected larval coral reef fishes at five locations surrounding two spatially disparate French Polynesian islands: Moorea and Nengo-Nengo. Overall, larval settlement patterns were correlated with the lunar cycle, with larval abundance peaking during the new moon. Although there were some spatial differences in larval supply among the five monitored sites, settlement patterns were largely consistent, even at the species level, irrespective of factors such as coastline orientation or distance between sites. This study provides further insights into the mechanisms driving patterns of dispersal and settlement of larval fishes over large spatial scales.

The present study tested different sounds that could disturb eagle rays (Aetobatus ocellatus) during their foraging activities at Moorea, French Polynesia. Results showed that artificial white sound and single-frequency tones (40 Hz, 600 Hz or 1 kHz) did not have an effect on rays (at least 90% of rays continued to forage over sand), while playbacks of boat motor sound significantly disturbed rays during foraging activity (60% exhibited an escape behaviour). Overall, our study highlighted the negative effect of boat noises on the foraging activity of eagle rays. These noises produced by boat traffic could, however, have some positive effects for marine aquaculture if they could be used as a deterrent to repel the eagle rays, main predators of the pearl oysters., (Copyright © 2016. Published by Elsevier SAS.)

When fish larvae recruit back to a reef, chemical cues are often used to find suitable habitat or to find juvenile or adult conspecifics. We tested if the chemical information used by larvae was intentionally produced by juvenile and adult conspecifics already on the reef (communication process) or whether the cues used result from normal biochemical processes with no active involvement by conspecifics ("spying" behavior by larvae). Conspecific chemical cues attracted the majority of larvae (four out of the seven species tested); although while some species were equally attracted to cues from adults and juveniles (Chromis viridis, Apogon novemfasciatus), two exhibited greater sensitivity to adult cues (Pomacentrus pavo, Dascyllus aruanus). Our results indicate also that spying cues are those most commonly used by settling fishes (C. viridis, P. pavo, A. novemfasciatus). Only one species (D. aruanus) preferred the odour of conspecifics that had had visual contact with larvae (communication)., (Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

Three experimental pilots were set up at the semi-industrial scale to assess the impact of leachate recirculation and Mechanical Biological Pre-treatment (MBP) before landfilling on the biological degradation of landfilled wastes. The organic matter contained in leachates resulting from these pilots has been used as an indicator of waste degradation. Fractionations were carried out (i) using XAD resins in order to divide the organic matter into several fractions according to the hydrophobic character of the molecules and (ii) using an ultrafiltration protocol to divide the organic matter into several fractions according to the apparent molecular weight of molecules. Three phases of degradation are determined according to the distribution of the organic matter and according to the humification rate. The humification process seems to be more rapid for MBP leachates than for Bioreactor leachate. These results were confirmed by the ultrafiltration results indicating that, to date, MBP leachates contain more molecules with a high molecular weight than Bioreactor leachate. However, this could be explained by an interruption of waste degradation due to an accumulation of volatile fatty acids.

Background: Nadroparin, a low-molecular-weight heparin (LMWH), is an alternative to unfractionated heparin for the acute management of patients with non-ST elevation acute coronary syndrome (ACS): unstable angina or non-Q-wave myocardial infarction. However, unfractionated heparin can be substituted for LMWH in patients requiring percutaneous coronary interventions (PCIs) for the duration of the procedure. The tolerability of this anti-thrombotic regimen (i.e. unfractionated heparin for the duration of PCIs, preceded and followed by subcutaneous injection of nadroparin) is not yet documented., Design and Methods: This open-label 6-day study was carried out in 302 patients to test the tolerability of this anti-thrombotic regimen in patients requiring PCIs. The primary end-point of the study was the incidence of major haemorrhage over the whole study duration (6 days). The secondary end-point was the need for transfusion and vascular repair after PCI., Results: The incidence of major haemorrhage in patients undergoing coronary angiography (CA) without or with PCIs was 1.4% and 1.3%, respectively, and the incidence of minor haemorrhage was 10.7% and 23.5%, respectively. These results are consistent with published data., Conclusions: These results suggest that CA and PCIs can be performed safely in patients being treated for unstable angina or non-Q-wave myocardial infarction receiving nadroparin pre- and post-coronary procedure and/or intervention, substituted by unfractionated heparin for the duration of the intervention.

Objectives: To assess the relative value of electrocardiographic, echocardiographic, angiographic, and in-hospital therapeutic indices for predicting late functional recovery after acute myocardial infarction, and to determine the variables associated with absence of recovery, partial recovery, and full recovery., Design: Prospective observational follow up study., Setting: Teaching hospital., Patients: 74 consecutive patients with a first uncomplicated acute myocardial infarct., Interventions: Dobutamine-atropine stress echocardiography was performed mean (SD) 5 (2) days after the acute event. Quantitative angiography was available in all patients before hospital discharge. A follow up resting echocardiogram was obtained 12 (2) months later., Results: Functional recovery (partial, n = 18; full, n = 27) was observed in 45 of the 74 patients. Recovery was associated with earlier thrombolytic treatment (p = 0.008), earlier peak concentration of creatine kinase (p = 0.009), greater contractile reserve (p = 0.0001), non-Q wave acute myocardial infarction (p = 0.002), and more frequent elective angioplasty of the infarct related vessel (p = 0.0004). Three independent variables were selected stepwise from multivariate analysis for predicting late recovery: contractile reserve (chi(2) = 24.2, p < 0.0001); non-Q wave infarction (chi(2) = 15.7, p = 0.0001); and the time from symptom onset to thrombolysis (chi(2) = 4.94, p = 0.026). Three independent variables predicted full recovery: contractile reserve (chi(2) = 17.2, p = 0.0001); non-Q wave infarction (chi(2) = 10.1, p = 0.0016); and elective angioplasty of the infarct related artery (chi(2) = 4.53, p = 0.033). Only contractile reserve (chi(2) = 17.0, p < 0.001) was selected from the multivariate analysis for its ability to distinguish between partial recovery and absence of recovery., Conclusions: Late recovery of contraction relates to earlier treatment, which is associated with lower infarct size unmasked by a non-Q wave event and the presence of contractile reserve. Elective coronary angioplasty of the infarct related artery before hospital discharge is associated with full recovery.

To assess the presence of viable myocardium salvaged by coronary artery reperfusion, 17 patients with acute anterior myocardial infarction were studied. Each received intravenous thrombolysis within the first 3 h of symptoms and underwent two-dimensional echocardiography before and during dobutamine infusion (10 micrograms/kg per min) 7 +/- 4 days after admission and positron emission tomography 9 +/- 5 days after admission. Echocardiography and positron emission tomography were again performed 9 +/- 7 months later. Six comparable segments specific for the territory of the left anterior descending artery were selected for comparison of the two techniques. Wall thickening was evaluated by using an echocardiographic score index. Segmental perfusion and glucose uptake were measured and normalized to the peak activity. A ratio of glucose uptake to perfusion was calculated for each segment. Concordant interpretation of the two techniques was found in 79% of affected segments for both acute and follow-up studies. Positron emission tomography revealed the presence of viable myocardium in 11 patients (group 1); perfusion was within normal limits in 5 of these (group 1A). Myocardial thickening improved with dobutamine infusion in these five patients, the echocardiographic score index decreasing from 12 +/- 2 at rest to 7.8 +/- 1.3 during dobutamine infusion (p = 0.003). Functional recovery was demonstrated in all five patients (follow-up score index 7.4 +/- 1.7). Six patients exhibited decreased perfusion but an abnormally high glucose to perfusion ratio (group 1B); their score index improved with dobutamine from 14.8 +/- 2.2 to 12 +/- 2.1 (p = 0.05), but late functional recovery was found in only one of the six patients (mean follow-up score index in group 1B 16 +/- 1.7). In the six remaining patients in whom no viable myocardium was detected with positron emission tomography (group 2), the echocardiographic score index did not change with dobutamine (15 +/- 0.9 to 14.7 +/- 0.8, p = NS) and there was no functional recovery (follow-up score index 15.5 +/- 1.0). Echocardiography during dobutamine infusion is a promising method to unmask viable myocardium in acute myocardial infarction. Early recovery of perfusion in the area at risk is associated with a good functional outcome, whereas a high glucose to perfusion ratio indicates jeopardized myocardium that frequently loses viability.

To identify the haemodynamic response to ischaemia induced by dobutamine stress testing, 15 patients with a first acute myocardial infarction underwent right-sided heart catheterization during dobutamine stress cross-sectional echocardiography. Haemodynamic variables and echocardiography were recorded at rest and during dobutamine infusion at each dose from 5 to a maximum of 40 micrograms kg-1 min-1. Ischaemia was diagnosed by cross-sectional echocardiography if asynergy appeared in at least two ventricular segments other than the area of acute myocardial infarction. Ischaemia was absent in six patients (group I) and identified in nine (group II). Response curves for each haemodynamic variable in the two groups were compared by applying Zerbe's method. The response curves were similar in the two groups for heart rate, arterial, right atrial, pulmonary arterial and pulmonary artery wedge pressures. The response curves were significantly different in groups I and II for thermodilution cardiac output, stroke volume and systemic vascular resistance (P less than 0.05). An increase in stroke volume was observed at low dosage of dobutamine in both groups. From low to maximum dose, stroke volume remained unchanged in group I and was significantly decreased in group II. Ischaemia induced by dobutamine stress testing leads to a decrease in stroke volume with no change in pulmonary artery wedge pressure.

The feasibility, safety and usefulness of 2-dimensional echocardiography (2-D echo) during dobutamine infusion for identifying patients with multivessel coronary artery disease (CAD) after acute myocardial infarction (AMI) were evaluated in 30 patients 5 to 10 days after AMI. Patients underwent 2-D echo under basal conditions and during dobutamine infusion at each dose from 5 to a maximum of 40 micrograms/kg/min, limited multilead submaximal bicycle exercise testing and coronary and left ventricular angiography. Echocardiograms were analyzed independently by 2 observers. The test response was considered positive if abnormal wall motion and reduced myocardial thickening were observed during dobutamine infusion in vascular distributions other than the area of infarction identified during basal conditions. Exercise testing was considered positive when more than 1 mm of ST depression occurred 80 ms after the J point. Dobutamine stress testing was well tolerated; no complications and no significant arrhythmia were observed. Echocardiographic recordings were adequate in all patients during the entire test; the concordance in interpretation between the 2 observers was perfect for the prediction and location of ischemic segments during dobutamine infusion. In 15 of 17 patients without multivessel CAD, no asynergy was observed outside the infarct zone during dobutamine infusion (specificity 88%). In 11 of 13 patients with multivessel CAD, new wall motion abnormalities were identified in the segments corresponding to the arterial lesions diagnosed by angiography (sensitivity 85%).(ABSTRACT TRUNCATED AT 250 WORDS)