Loïc Martin
email: loic.martin@chu-rouen.fr

Jean-Marc Baste

Dochead dossier Sous-dochead Accompagner la pluriprofessionnalité Simulation d'équipe pour l'apprentissage des process et des situations de crise au service de la pluriprofessionnalité

Keywords: bloc opératoire, briefing préopératoire, check-list, débriefing, équipe pluridisciplinaire, sécurité du patient, simulation, staff

et chef du pôle des blocs opératoires, livre l'impact positif sur la dynamique pluriprofessionnelle de la mise en place de la simulation d'équipe pour appréhender des process et s'entraîner à des situations de crise au sein du bloc. Le briefing, le débriefing, mais aussi l'importance de la pédagogie dans cette modalité apparaissent être des points clés garantissant une réussite collective.

aux process de sécurité, est qu'en étant attentif au travailler ensemble, j'observe une amélioration de la performance de l'équipe en termes d'efficience avec une meilleure rentabilité tout en conservant une qualité de vie au travail. Le respect des aides cognitives, comme les check-lists, permet de structurer la collaboration pluridisciplinaire avec un temps de briefing et de débriefing au cours d'une intervention. Ces concepts sont issus des entreprises de haute sécurité, comme l'aéronautique mais aussi de la simulation médicale.

Soins Cadres. Pouvez-vous nous préciser les innovations que vous avez développées au bloc opératoire sur ce sujet du travail d'équipe ? J.-M. B. Nous sommes partis de situations de crise en chirurgie mini-invasive que nous avons débriefées pour ensuite travailler sur ces éléments en rédigeant des scénarios afin d'adapter nos pratiques. Nous utilisons les méthodes structurées de débriefing des événements indésirables, comme celle du comité de retour d'expérience (Crex) ou Orion. Nous nous sommes rendu compte que la check-list était impérative. Mais nous voulions pousser cette approche un peu plus loin. Nous allons au-delà de l'identito-vigilance, en instaurant un briefing préopératoire pour que l'ensemble de l'équipe pluriprofessionnelle soit attentive aux objectifs et aux possibles points critiques de l'intervention. Nous avons transformé cette check-list en temps de briefing. Cela permet de partager avec l'ensemble de l'équipe (médicale et paramédicale) les objectifs de l'opération et ainsi de garantir la connaissance de la situation pour tous au même moment. De plus, au cours de ces scénarios de crise, nous avons identifié des éléments récurrents (aspirations de sécurité, clamps, etc.) qui pouvaient être anticipés quelle que soit la place du professionnel au sein du bloc opératoire. Cela permet de diminuer collectivement le stress au moment de la crise et de sécuriser les pratiques professionnelles. Partant de ce travail, nous avons décidé d'implémenter cette check-list de crise. Nous l'avons complétée par la simulation. Cette association nous apparaît être la meilleure méthode d'apprentissage en équipe d'un parcours structuré obligatoire de sécurité patient. Ce qui est innovant, c'est l'apprentissage en équipe pluriprofessionnelle in situ, c'est-à-dire dans l'environnement du bloc opératoire. L'objectif principal de l'apprentissage de ces process est double : répondre collectivement et en harmonie à deux scénarios : le premier, classique, celui d'une intervention qui se passe normalement, le second, celui d'un scénario catastrophe, de crise. Je dois reconnaître que cela a transformé la manière de travailler de l'ensemble de l'équipe : les chirurgiens, les anesthésistes, l'ensemble des paramédicaux.

Soins Cadres. Quels changements et points forts avez-vous pu observer chez les différents professionnels à la suite de la mise en oeuvre de cette simulation d'équipe pour l'apprentissage des process et l'entraînement à des situations de crise rares ?

J.-M. B. Malgré la complexité de la mise en oeuvre de ce programme en termes d'organisation et de logistique, les professionnels adhèrent totalement à son déploiement. Nous transformons une équipe habituée à une organisation hiérarchique en une équipe organisée autour d'un leader. Ce qui me semble également intéressant, c'est la compréhension de ce qui se passe pour l'ensemble du personnel et le fait d'intégrer l'équipe d'anesthésistes au sein de l'équipe chirurgicale. Car il faut reconnaître qu'historiquement ces deux équipes avaient tendance à travailler en parallèle. Avec une vraie séparation physique symbolisée par le champ opératoire. Il est vrai que cette simulation pluriprofessionnelle permet de remettre chacun sur la même page et c'est ce qu'on appelle en anglais le shared mental model 1 , c'est-à-dire que tout le personnel partage la compréhension de la situation au même moment. Chacun comprend ce que son collaborateur est en train de faire. Car au cours d'une intervention, il existe de nombreuses ruptures, distractions, et les professionnels s'éloignent. Le chirurgien ou l'anesthésiste, qui joue le rôle de leader, doit recentrer les professionnels sur leurs tâches individuelles mais aussi collectives. En outre, aujourd'hui avec les nouvelles technologies qui transforment complètement la communication et le travail en équipe avec cette interface, nous avons besoin encore plus de ces qualités non techniques, que l'on appelle les facteurs humains ou soft skills, c'est-à-dire les compétences comportementales.

Soins Cadres. Qu'est-ce qu'a changé cette approche au niveau de la pluriprofessionnalité ? J.-M. B. Comme je l'ai précisé, la communication pluriprofessionnelle a évolué. Elle est meilleure et beaucoup plus objective. J'ai remarqué également une planification et une coordination plus adaptées entre les soignants. Lors des moments de crise ou d'intensité, ils sont capables de se reconcentrer plus rapidement qu'auparavant, car ils savent que c'est important. Je dois dire que la montée en compétence est réelle et que l'ensemble de l'équipe est fière de cette évolution. Ils sont d'autant plus fiers que lorsque des professionnels d'autres établissements de santé viennent observer les pratiques des équipes du bloc, les compliments se font autant sur la partie technique que la partie non technique. D'ailleurs, lorsque j'effectue des master class de chirurgie robotique sur ce sujet en France et à l'étranger, j'insiste sur les deux dimensions chirurgicales qui sont techniques et non techniques (des apports sur la sécurité et sur la performance). J'y aborde les check-lists de crise, le briefing et le débriefing, mais aussi la notion de planification de l'acte opératoire. Il y a la programmation en amont et la planification juste avant l'acte. Les retours sont très positifs après avoir expérimenté cette approche. Les chirurgiens et les équipes se sentent plus efficaces. Les explications du déroulé opératoire permettent à tous de savoir ce qui va être fait, les différentes étapes de la séquence opératoire et d'anticiper les événements à risque.

Soins Cadres. Cette nouvelle modalité a-t-elle transformé votre style de management ?

J.-M. B. Effectivement, je suis passé d'un style de management plutôt hiérarchique à un management plus transversal et anticipé. Cela n'a pas changé ma détermination sur les améliorations, mais la méthode pour y arriver a complètement changé. Elle est beaucoup plus efficace. Lorsque je veux changer quelque chose qui me déplaît, je sais que je vais passer par des séances de simulation et des réunions structurées à froid. Le bloc opératoire, qui est un espace de tension, n'est pas du tout un environnement d'apprentissage. C'est un travail beaucoup plus profond et plus efficace. Mais cela demande plus de temps, car il faut organiser des réunions en dehors du temps opératoire. Le résultat est là, et je souhaite instaurer cet état d'esprit dans l'ensemble des blocs opératoires du CHU où j'exerce. C'est une priorité. C'est en partie pour cela que j'ai pris la responsabilité du pôle des blocs. Je veux changer les mentalités avec un accent mis sur la check-list, le briefing et le débriefing et, bien sûr, le travail d'équipe. C'est une culture qui se met en place, notamment avec les plus jeunes. Nous les acculturons avec des cours où nous mélangeons les internes de chirurgie et d'anesthésie, pour que chacun comprenne les process des différentes spécialités. Maintenant, l'étape d'après est d'intégrer les élèves infirmiers de bloc opératoire diplômés d'État (Ibode) et infirmiers anesthésistes diplômé d'État (Iade). Il s'agit d'un management de l'enseignement. C'est-à-dire que si nous souhaitons changer les pratiques, cela passe inévitablement par beaucoup de pédagogie.

Soins Cadres. Cela a donc un impact aussi bien sur la qualité des soins que sur la qualité de vie au bloc opératoire ? J.-M. B. Oui, bien sûr, tout est lié. C'est pour cela que lorsque j'ai commencé, l'objectif principal de cette aventure était la sécurité autant pour le patient que pour les équipes pluriprofessionnelles. Au-delà de la sécurité et de la rentabilité, nous libérons une puissance d'équipe énorme en termes d'efficience. Par exemple, aujourd'hui, nous sommes capables de faire trois procédures robotiques de chirurgie lourde sur une plage opératoire alors qu'en moyenne elle est de deux.

Soins Cadres. Avez-vous transféré cette expérience dans les unités de soins ?

J.-M. B. Oui, d'ailleurs je l'ai proposée à plusieurs reprises sur l'appropriation des protocoles. Mais il y a un vrai travail à faire également de la part des cadres de santé de proximité et des infirmier(ère)s. Il faut que ces derniers écrivent des protocoles pour se l'approprier. Concrètement, nous pourrions faire de la simulation sur de petits scénarios ou sur un retour d'expérience pour obliger les professionnels à comprendre la simplification des soins. L'objectif dans un service est de simplifier les soins pour améliorer la sécurité, mais aussi la rentabilité puisqu'il y a moins d'interruptions de tâches. J'y crois beaucoup, et d'ailleurs le service a largement augmenté son activité sans moyens supplémentaires.

Soins

Cadres. Quelles seraient demain les pistes d'avenir qui impulseraient une dynamique de pluridisciplinarité ? J.-M. B.

  Il s'agit des staffs hebdomadaires avec les infirmiers diplômés d'État (IDE), cadres, chirurgiens, soignants au cours desquels on discute des protocoles et des retours d'expérience. Cela pourrait être très simple, d'une durée d'un quart d'heure, car l'activité clinique est un moment "chaud" et ce n'est pas un moment d'apprentissage. Je pense que les IDE et les cadres seraient intéressés par ce process global, mais cela demande de réorganiser le circuit et de réfléchir à la concordance des temps médicaux-paramédicaux. C'est-à-dire laisser du temps pour la pédagogie. En fait, ce que je vais faire dans les six mois qui viennent, lors du staff du mercredi matin, est d'augmenter sa durée. Il aura lieu de 8 heures à 10 h 30 et sera découpé en plusieurs temps. Dans la première partie, les patients seront visités trente minutes, ensuite il est prévu de parler "universitaire" avec les internes, et pour les secrétaires, les cadres, et les IDE d'évoquer les petits "irritants" de la semaine pour les améliorer. L'objectif serait ensuite que les IDE et les cadres puissent écrire dans un mode agile les protocoles d'amélioration de soins. En conclusion, la pluriprofessionnalité et la multidisciplinarité, c'est-à-dire le travail d'équipe tout simplement, ne sont pas un concept si simple ni stable dans le temps. Il demande un travail de pédagogie régulier et structuré où la simulation d'équipe est l'élément essentiel.

	Propos

recueillis par Loïc Martin Note 1

  En psychologie cognitive, un modèle mental est une représentation permettant de simuler mentalement le déroulement d'un phénomène pour anticiper les résultats d'une action. Déclaration de liens d'intérêts L'auteur déclare ne pas avoir de liens d'intérêts.


Flora Kochly

Christelle Haddad

Brahim Harbaoui

Claire Falandry

Pierre Lantelme

Pierre-Yves Courand
email: pierre-yves.courand@chu-lyon.fr

Therapeutic management and outcome of nonagenarians versus octogenarians admitted to an intensive care unit for acute coronary syndromes

Background. -The number of very old patients admitted to intensive care units for acute coronary syndromes has increased gradually, but these patients are under-represented in randomized clinical trials.

Aim. -The aim of this study was to analyse mortality of nonagenarians compared with octogenarians admitted to an intensive care unit for acute coronary syndromes, to describe their management and to identify prognostic factors.

Methods. -Patients aged ≥ 80 years admitted to an intensive care unit (Croix-Rousse University Hospital, Lyon) with a diagnosis of acute coronary syndrome from 1 January 2013 to 31 December 2016 were included retrospectively. After exclusion of type 2 acute coronary syndromes, the data for 311 octogenarians and 92 nonagenarians were analysed using Kaplan-Meier curves and a multivariable Cox regression model.

Results. -More than 70% of patients received renin-angiotensin-system blockers, beta-blockers and statins, without significant difference between nonagenarians and octogenarians. Nonagenarians were treated significantly less frequently with ticagrelor than octogenarians (P = 0.028). Overall, 97.8% of patients had a coronary angiogram, and 80.4% underwent percutaneous coronary intervention. At 5year follow-up, the survival rate was 62.8% for nonagenarians compared with 73.1% for octogenarians (P = 0.007), but no significant difference was observed for cardiovascular mortality (P = 0.17). Global Registry of Acute Coronary Events (GRACE) score and increased age were significantly associated with higher mortality rate, while renin-angiotensin-system blockers, statins and ticagrelor were protective factors.

Conclusions. -Although overall mortality was higher in patients aged ≥ 90 years compared with those aged < 90 years with acute coronary syndromes, the overall survival reported here is acceptable. In addition to the effect of age, the difference in prognosis according to age may be explained, in part, by a non-optimal treatment strategy for older patients.

Résumé

Contexte. -La proportion des patients très âgés admis en soins intensifs cardiologiques (USIC) pour un syndrome coronaire aigu (SCA) a progressivement augmenté. Cette population est sous représentée dans les études randomisées.

Objectif. -L'objectif est d'évaluer la mortalité des nonagénaires en comparaison des octogénaires admis pour un SCA en USIC et d'identifier les facteurs influençant le pronostic.

Méthodes. -Les patients ≥ 80 ans admis à l'USIC (Hôpital de la Croix-Rousse, CHU de Lyon) avec un diagnostic de SCA ont été analysés rétrospectivement entre le 01 Janvier 2013 et le 31 décembre 2016. Après exclusion des SCA de type 2, les données de 311 octogénaires et 92 nonagénaires ont été analysés par les courbes de Kaplan-Meier et les modèles de Cox ajustés.

Résultats. -Plus de 70 % des patients ont été traités par les bloqueurs du système rénineangiotensinogène (BSRA), les béta-bloquants et statines sans différence significative selon l'âge. Les nonagénaires étaient moins fréquemment traités par le ticagrelor que les octogénaires (P = 0,0028). 97,8 % des patients ont été explorés par une coronarographie, et 80,4 % une angioplastie coronaire.

A 5 ans de suivi, la survie toute cause était de 62,8 % pour les nonagénaires contre 73,1 % pour les octogénaires (P = 0,007) avec une tendance non significative pour la mortalité cardiovasculaire (P = 0,17). L'âge avancé et le score de GRACE est significativement associé à la mortalité toute cause, à l'inverse les BSRA, les statines et le ticagrelor étaient des facteurs protecteurs.

Conclusions. -Malgré une mortalité supérieure chez les nonagénaires, leur survie globale paraît acceptable. Au-delà de l'effet de l'âge sur la mortalité, la surmortalité des nonagénaires pourrait s'expliquer par une moindre optimisation de la thérapeutique.

KEYWORDS

Background

Older patients account for an increasing proportion of patients admitted to hospital with acute coronary syndromes (ACS); currently about one-third are aged ≥ 75 years [START_REF] Belle | French Registry on Acute ST-elevation and non-ST-elevation Myocardial Infarction 2015 (FAST-MI 2015). Design and baseline data[END_REF]. At the same time, older patients are either excluded or under-represented in randomized controlled trials investigating the benefits of ACS treatments [START_REF] Alexander | Acute coronary care in the elderly, part II: STsegment-elevation myocardial infarction: a scientific statement for healthcare professionals from the American Heart Association Council on Clinical Cardiology: in collaboration with the Society of Geriatric Cardiology[END_REF][START_REF] Alexander | Acute coronary care in the elderly, part I: Non-ST-segment-elevation acute coronary syndromes: a scientific statement for healthcare professionals from the American Heart Association Council on Clinical Cardiology: in collaboration with the Society of Geriatric Cardiology[END_REF][START_REF] Krumholz | Is there evidence of implicit exclusion criteria for elderly subjects in randomized trials? Evidence from the GUSTO-1 study[END_REF][START_REF] Lee | Representation of elderly persons and women in published randomized trials of acute coronary syndromes[END_REF]. This group of patients is known to be at higher risk of both ischaemic events and bleeding complications, making it difficult to determine the most appropriate therapy. Current guidelines do not detail a specific management strategy for this population, but propose performing an overall estimation of patient status, including general health, cognitive status and life expectancy [START_REF] Ibanez | ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation: The Task Force for the management of acute myocardial infarction in patients presenting with ST-segment elevation of the European Society of Cardiology (ESC)[END_REF][START_REF] Kushner | Focused Updates: ACC/AHA Guidelines for the Management of Patients With ST-Elevation Myocardial Infarction (updating the 2004 Guideline and 2007 Focused Update) and ACC/AHA/SCAI Guidelines on Percutaneous Coronary Intervention (updating the 2005 Guideline and 2007 Focused Update): a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines[END_REF][START_REF] Prejean | Guidelines in review: Comparison of the 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes and the 2015 ESC guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation[END_REF][START_REF] Roffi | ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: Task Force for the Management of Acute Coronary Syndromes in Patients Presenting without Persistent ST-Segment Elevation of the European Society of Cardiology (ESC)[END_REF].

In parallel, over the past decade, the added prognostic value of an invasive approach, particularly percutaneous coronary intervention (PCI), has been demonstrated for ST-segment elevation myocardial infarction (STEMI) [START_REF] Bueno | Primary angioplasty vs fibrinolysis in very old patients with acute myocardial infarction: TRIANA (TRatamiento del Infarto Agudo de miocardio eN Ancianos) randomized trial and pooled analysis with previous studies[END_REF][START_REF] Mandawat | Percutaneous coronary intervention after STsegment elevation myocardial infarction in nonagenarians: use rates and in-hospital mortality[END_REF][START_REF] Petroni | Primary percutaneous coronary intervention for ST elevation myocardial infarction in nonagenarians[END_REF][START_REF] Rigattieri | Primary percutaneous coronary intervention in nonagenarians: six-month outcomes from a single-center registry[END_REF] and non-STEMI (NSTEMI) [START_REF] Bach | The effect of routine, early invasive management on outcome for elderly patients with non-ST-segment elevation acute coronary syndromes[END_REF][START_REF] Reinius | Percutaneous coronary intervention versus conservative treatment for non ST-segment elevation myocardial infarction in patients above 80years of age[END_REF]. Such therapeutic management has moved progressively to the older population, and clinical benefit has been observed in this subgroup, mainly in cohort studies [START_REF] Alexander | Evolution in cardiovascular care for elderly patients with non-ST-segment elevation acute coronary syndromes: results from the CRUSADE National Quality Improvement Initiative[END_REF][START_REF] Amann | Acute myocardial infarction in the elderly: Treatment strategies and 28-day-case fatality from the MONICA/KORA myocardial infarction registry[END_REF][START_REF] Hovanesyan | Outcomes of acute myocardial infarction in nonagenarians[END_REF][START_REF] Nauta | Age-dependent care and long-term (20 year) mortality of 14,434 myocardial infarction patients: changes from 1985 to 2008[END_REF]. However, the concept of frailty, the higher prevalence of comorbidities, age-associated conditions (cognitive and functional impairment) and a higher risk of complications might explain why clinicians frequently use either conservative or selective invasive approaches in older patients in real-world practice [START_REF] Ariza-Sole | Impact of frailty and functional status on outcomes in elderly patients with ST-segment elevation myocardial infarction undergoing primary angioplasty: rationale and design of the IFFANIAM study[END_REF][START_REF] Flaatten | The impact of frailty on ICU and 30-day mortality and the level of care in very elderly patients (>/= 80 years)[END_REF]. In the context of an ageing population, the prognosis of ACS in older patients appears to be of utmost importance. However, only a few studies have focused on daily routine practice concerning this specific population.

The aim of this study was therefore to analyse mortality of nonagenarians compared with octogenarians admitted to an intensive care unit (ICU) for ACS, to describe their therapeutic management and to identify prognostic factors.

Methods

Population

Patients aged ≥ 80 years and admitted for ACS to the ICU of the Croix-Rousse University Hospital (Hospices Civils de Lyon, France) were included retrospectively using the hospital discharge database (Programme de médicalisation des systems d'information [PMSI]). All patients with a hospital stay between 1 January 2013 and 31 December 2016 and with a diagnosis of ACS at admission were identified, and differential diagnoses were excluded after investigation of medical records. For patients with several hospital stays, only the first stay was considered in the analysis. Patients were classified according to the type of myocardial infarction (STEMI, type 1 NSTEMI or type 2 NSTEMI) and age (80-90 or ≥ 90 years). Type 2 NSTEMI was defined when a specific clinical setting (anaemia, arrhythmias, sepsis) that might explain a myocardial oxygen demand mismatch was observed.

Patients with type 2 NSTEMI were excluded from the analysis.

Data collection

The following data were collected from electronic medical files: demographic characteristics (age, sex and residence in nursing home); comorbidities (hypertension, diabetes, atrial fibrillation and cognitive function); clinical presentation at admission (blood pressure, heart rate, Killip classification and cardiac arrest); laboratory data (plasma creatinine and haemoglobin); medical therapies; and invasive management. Significant valvular heart disease was defined after transthoracic echocardiography with the following criteria: mitral regurgitation ≥ grade 3; aortic regurgitation ≥ grade 3; moderate or severe aortic stenosis; and moderate or severe mitral stenosis. The defined daily dose (DDD) of administered drug was determined according to the World Health Organization Collaborating Centre for Drugs Statistics Methodology DDD system [START_REF] Whocc | DDD: Definition and general considerations[END_REF]. DDD is defined as "the assumed average maintenance dose per day for a drug used for its main indication in adults" [START_REF] Whocc | DDD: Definition and general considerations[END_REF]. This system makes it possible to perform standardized comparisons of antihypertensive drug use for patients on different drugs.

A Global Registry of Acute Coronary Events (GRACE) score at admission was calculated using the above-mentioned variables, as was a GRACE score excluding the variable age to compare patients aged 80-89 and ≥ 90 years [START_REF] Pieper | Validity of a risk-prediction tool for hospital mortality: the Global Registry of Acute Coronary Events[END_REF]. Vital status was obtained using the last follow-up medical visit. Intrahospital haemorrhagic events were reported using Bleeding Academic Research Consortium (BARC) criteria [START_REF] Mehran | Standardized bleeding definitions for cardiovascular clinical trials: a consensus report from the Bleeding Academic Research Consortium[END_REF].

Statistical analysis

Continuous variables with normal distributions are summarized as means ± standard deviations, and categorical variables as counts and percentages. Analysis of variance (ANOVA) and χ 2 tests were used for group comparisons for continuous and categorical variables, respectively. Paired comparisons were made between type of ACS, using the Tukey correction for multiple testing on continuous variables, and the Bonferroni correction for multiple testing on categorical variables. Allcause death and cardiovascular death (myocardial infarction, cardiogenic shock, cerebral infarction, heart failure and sudden death) were estimated using the Kaplan-Meier method (log-rank statistic) according to different subgroups of patients (age 80-89 vs ≥ 90 years, type of ACS) and by univariate Cox regression models. The proportional hazards hypothesis was tested for each variable by introducing a variable-by-time interaction into the Cox regression model. These interactions were not statistically significant for all-cause or cardiovascular death. A backward multivariable Cox regression model was then built with the inclusion of variables with a P value < 0.10 in the univariate analysis to determine the independent predictors of mortality. An additional sensitivity analysis was carried out after exclusion of patients who died during the initial hospital stay. Analyses were performed using SPSS software, release 20.0.0 (SPSS, Chicago, IL, USA). P < 0.05 was considered statistically significant.

Results

Baseline characteristics

Among the 476 patients considered, 403 were included with type 1 NSTEMI or STEMI (Fig. 1).

Compared to included patients, patients with type 2 NSTEMI had different characteristics at admission, including significantly higher systolic blood pressure, heart rate and left ventricular ejection fraction (LVEF) and lower haemoglobin, and presented more frequently with atrial fibrillation and diabetes (Table A.1). Concerning included patients, nonagenarians less frequently had diabetes and smoked, but more frequently had dementia than octogenarians. There was also a significant difference in the number of coronary arteries affected according to age. Mean GRACE score (including or excluding age) was not significantly different between the two groups (Table 1). During their hospital stay, 43 patients (10.7%) developed new-onset atrial fibrillation, with no difference between nonagenarians and octogenarians (n = 12, 13.0% vs n = 31, 10.0%, respectively; P = 0.40).

Therapeutic management

Around three-quarters of patients received angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACE inhibitors/ARBs), beta-blockers or statins, without significant difference between age groups. Half of the patients received loop diuretics during their hospital stay, and 10.2% received inotropes/vasopressor agents. No ventilation was used in nonagenarian patients (Table 2).

There was no significant difference in the proportions of patients receiving beta-blockers, ACE inhibitors/ARBs and statins between the two age groups (Fig. 2A). However, nonagenarians received a lower mean DDD of drugs than octogenarians for beta-blockers, ACE inhibitors/ARBs and statins (Fig. 2B). Optimal doses of treatment were achieved in a minority of both nonagenarians (ACE inhibitors/ARBs 3.0%, beta-blockers 5.1%, statins 10.9%, mineralocorticoid receptor antagonists [MRAs] 1.1%) and octogenarians (ACE inhibitors/ARBs 18.3%, beta-blockers 13.3%, statins 28.3%, MRAs 3.2%). There was a significantly lower frequency of ticagrelor use in nonagenarians, whereas glycoprotein IIb/IIIa inhibitors (1.0%) and prasugrel (0.2%) were used infrequently in both groups. Lowmolecular-weight heparin was the most frequently used anticoagulant drug in the two subgroups (41.2% and 39.1%, respectively) (Table 2 and Fig. 2C). Nearly all patients (97.8%) had a coronary angiogram during the hospital stay. PCI was performed in 80.4% of patients and radial access was used in 92.1% of cases (Table 2). Device closure was used in 19 patients (61.2%) in whom femoral access was used. Among nonagenarians, bare-metal stents were more frequent than drug-eluting stents, whereas the converse was found among younger patients (P = 0.001; Table 2 and Fig. 2D). A small proportion of patients (6.1%) were treated without stent implantation (balloon angioplasty or aspiration thrombectomy). Haemorrhagic events, mostly of gastrointestinal, urological or vascular origin, occurred in 20.0% of nonagenarians and 11.7% of octogenarians (P = 0.052); there was no significant difference in major bleeding (defined as BARC score > 2) between the two subgroups (P = 0.42; Fig. 3). Among the 43 patients who had new onset of atrial fibrillation during their hospital stay, nine were treated with vitamin K antagonists and three with direct oral anticoagulants at discharge. Among these 12 patients, only three were also treated with ticagrelor and aspirin; the others received clopidogrel and aspirin.

Mortality and outcome

The mean length of hospital stay in ICU was 2.4 ± 2.2 days in the whole cohort (n = 403), with no significant difference between nonagenarians (2.5 ± 2.4) and octogenarians (2.4 ± 2.2 days) (P = 0.82). The mean total length of full hospital stay was 6.1 ± 6.5 days in the whole cohort, without difference between nonagenarians (6.4 ± 6.9) and octogenarians (6.0 ± 6.3) (P = 0.56). The in-hospital mortality rate was 9.3% (n = 29) for octogenarians and 15.2% (n = 14) for nonagenarians. Before returning home, 37.2% of patients were admitted to a rehabilitation centre (40.2% of nonagenarians, 36.3% of octogenarians; P = 0.50). During the follow-up period (mean duration 3.2 ± 1.8 years), 108 deaths in the whole cohort (n = 403) were recorded (34 in nonagenarians, 74 in octogenarians), 51 of which were from cardiovascular causes (15 in nonagenarians, 36 in octogenarians). At 5-year followup, the overall survival was estimated to be 62.8% for nonagenarians and 73.1% for octogenarians, with a significantly higher risk of all-cause mortality for nonagenarians during follow-up (log-rank P = 0.007; Fig. 4A), and a similar (but non-significant) trend regarding cardiovascular mortality (log-rank P = 0.17; Fig. 4B). After stratification according to the type of ACS (STEMI versus NSTEMI), a significant difference was found between nonagenarians and octogenarians for all-cause mortality (log-rank P ˂ 0.001; Fig. 4C) and for cardiovascular mortality (log-rank P = 0.004; Fig. 4D).

Factors associated (P < 0.1) with all-cause and/or cardiovascular mortality in the univariate analysis (Table A.2) were included in a multivariable Cox regression model. Significant risk factors for all-cause mortality were older age and the necessity for inotrope use. Protective factors were use of ACE inhibitors/ARBs, statins and ticagrelor. A trend towards a negative association with beta-blocker use and a positive association with higher GRACE score were also shown. Significant risk factors for cardiovascular mortality were a higher GRACE score and necessity for inotrope use. Protective factors were use of ACE inhibitors/ARBs, ticagrelor and statins, and non-invasive ventilation (Table 3). After exclusion of patients who died during their initial hospital stay (n = 43), ticagrelor and ACE inhibitors/ARBs appeared to be protective factors against all-cause mortality, and inotropes and furosemide were associated with poorer survival. Finally, normal LVEF, ticagrelor and ACE inhibitors/ARBs were protective factors against cardiovascular mortality, whereas necessity for inotrope use was a strong predictor of pejorative outcome (Table A.3).

Discussion

The therapeutic approach used here in a selected older population seems appropriate, highlighting the fact that such patients can benefit from ICU admission and an invasive management strategy. The present study has demonstrated that the survival of older patients aged ≥ 90 years admitted to an ICU for myocardial infarction (STEMI or type 1 NSTEMI) was significantly lower for all-cause mortality, and there was a trend towards it being lower for cardiovascular mortality in comparison with those aged 80-89 years. Prognostic factors were identified, and these included admission status (GRACE score, cardiogenic shock and requirement for non-invasive ventilation), as well as specific therapeutic classes (ACE inhibitors/ARBs, statins and ticagrelor). Moreover, we observed that patients aged ≥ 90 years were less frequently treated with optimal management, which may explain, at least in part, the difference in outcomes observed. The 5-year overall survival estimated in this cohort of ACS patients (73.1% for octogenarians and 62.8% for nonagenarians) appears acceptable, given that the median survival rates observed in France in the general population among those of same age and over the same period were 5.9 and 3.8 years, respectively [START_REF]Tables de mortalité par sexe, âge et niveau de vie: Échantillon démographique permanent -Insee Résultats[END_REF].

The prognosis of patients with ACS is strongly influenced by age, and this variable has been included in the GRACE score that is recommended for risk stratification in the guidelines [START_REF] Pieper | Validity of a risk-prediction tool for hospital mortality: the Global Registry of Acute Coronary Events[END_REF].

Previous studies performed between 2006 and 2013 demonstrated that nonagenarian patients had a 1-year mortality rate close to 50%, which was four times higher than that for the general population at the same time (10-13%) [START_REF] Petroni | Primary percutaneous coronary intervention for ST elevation myocardial infarction in nonagenarians[END_REF][START_REF] Hovanesyan | Outcomes of acute myocardial infarction in nonagenarians[END_REF][START_REF] Jernberg | Association between adoption of evidence-based treatment and survival for patients with ST-elevation myocardial infarction[END_REF]. Many studies have highlighted temporal improvements in mortality from ACS, and most advances have concerned older patients [START_REF] Alabas | Age-dependent improvements in survival after hospitalisation with acute myocardial infarction: an analysis of the Myocardial Ischemia National Audit Project (MINAP)[END_REF]. Of note, in patients aged > 75 years, 5-year mortality decreased from 55% in the 1990s to 40% in 2008 [START_REF] Nauta | Age-dependent care and long-term (20 year) mortality of 14,434 myocardial infarction patients: changes from 1985 to 2008[END_REF]. The 5-year overall survival rate found in our study is indicative of an overall improvement during the past decade in a selected older population admitted to an ICU.

Medical practices have evolved quickly in the field of ACS, with new drugs (new P2Y12 inhibitors) and interventional techniques (development of coronary angiogram preferentially through the radial route, superiority of drug-eluting stents, etc.) [START_REF] Sabate | Clinical outcomes in patients with ST-segment elevation myocardial infarction treated with everolimus-eluting stents versus bare-metal stents (EXAMINATION): 5-year results of a randomised trial[END_REF][START_REF] Valgimigli | Radial versus femoral access in patients with acute coronary syndromes undergoing invasive management: a randomised multicentre trial[END_REF]. Despite an increased number of older patients being admitted to ICUs, they are largely under-represented in randomized controlled trials. This is probably caused, in part, by the caution that can be applied concerning the safety of testing new drugs in elderly patients. Ticagrelor became available on the French market in 2012, just before the start of the study, which may explain why older patients in our study were found to be undertreated using this new drug. In the PLATO study, patients aged > 75 years represented around 15% of those included, but the proportions of patients aged > 80 years or > 90 years were not mentioned [START_REF] Wallentin | Ticagrelor versus clopidogrel in patients with acute coronary syndromes[END_REF]. Nevertheless, in a substudy of PLATO, patients aged > 75 years had similar clinical benefit and overall safety to younger patients with ticagrelor compared with clopidogrel [START_REF] Husted | Ticagrelor versus clopidogrel in elderly patients with acute coronary syndromes: a substudy from the prospective randomized PLATelet inhibition and patient Outcomes (PLATO) trial[END_REF]. In the present cohort, ticagrelor was found to have a strong protective effect on mortality, sustaining the hypothesis that clopidogrel resistance might be more frequent in this population. This may encourage the prescription of ticagrelor in older patients who are not at very high risk of bleeding [START_REF] Silvain | High on-thienopyridine platelet reactivity in elderly coronary patients: the SENIOR-PLATELET study[END_REF]. However, this option may sometimes be counterbalanced by the high frequency of atrial fibrillation in older patients (> 20% in our study), which could explain the choice of clopidogrel in association with an anticoagulant to lower the risk of bleeding [START_REF] Ibanez | ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation: The Task Force for the management of acute myocardial infarction in patients presenting with ST-segment elevation of the European Society of Cardiology (ESC)[END_REF].

Other pharmacological treatments, including ACE inhibitors/ARBs, beta-blockers and statins, may be crucial for the outcome of patients after ACS. In the 2005 GRACE and CRUSADE studies, the use of beta-blockers and statins was reported to be less frequent among older patients at discharge [START_REF] Alexander | Evolution in cardiovascular care for elderly patients with non-ST-segment elevation acute coronary syndromes: results from the CRUSADE National Quality Improvement Initiative[END_REF][START_REF] Silvain | High on-thienopyridine platelet reactivity in elderly coronary patients: the SENIOR-PLATELET study[END_REF][START_REF] Avezum | Impact of age on management and outcome of acute coronary syndrome: observations from the Global Registry of Acute Coronary Events (GRACE)[END_REF]. Nevertheless, the rates of beta-blocker and statin prescriptions increased from 2003 to 2010 (49% to 56% and 61% to 68%, respectively) [START_REF] Gale | Resolving inequalities in care? Reduced mortality in the elderly after acute coronary syndromes. The Myocardial Ischaemia National Audit Project 2003-2010[END_REF]. Importantly, these treatments, as well as ACE inhibitors, have demonstrated greater clinical benefit in those with heart failure and reduced LVEF [START_REF] Alexander | Acute coronary care in the elderly, part II: STsegment-elevation myocardial infarction: a scientific statement for healthcare professionals from the American Heart Association Council on Clinical Cardiology: in collaboration with the Society of Geriatric Cardiology[END_REF][START_REF] Fleg | Secondary prevention of atherosclerotic cardiovascular disease in older adults: a scientific statement from the American Heart Association[END_REF]. As nearly half of the present cohort presented with heart failure at admission, this could partly explain the observed protective effect of these different classes of treatments, which were prescribed frequently in our study.

In patients aged > 70 years admitted for STEMI or NSTEMI, the proportion who were treated by PCI increased progressively from 4% in 2001 to nearly 70% in 2012 [START_REF] Amann | Acute myocardial infarction in the elderly: Treatment strategies and 28-day-case fatality from the MONICA/KORA myocardial infarction registry[END_REF][START_REF] Ariza-Sole | Impact of frailty and functional status on outcomes in elderly patients with ST-segment elevation myocardial infarction undergoing primary angioplasty: rationale and design of the IFFANIAM study[END_REF]. In our study, the majority of older patients admitted to the ICU had a coronary angiogram, and > 80% of them were treated by PCI. Drug-eluting stents were less frequently implanted in nonagenarians than in octogenarians, but the implantation rate was still 10 times higher than that reported for nonagenarians between 2003 and 2011 (4%) [START_REF] Helft | Outcomes of primary percutaneous coronary interventions in nonagenarians with acute myocardial infarction[END_REF]. This is probably because of a change in practice during the study recruitment period, in accordance with clinical guidelines [START_REF] Ibanez | ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation: The Task Force for the management of acute myocardial infarction in patients presenting with ST-segment elevation of the European Society of Cardiology (ESC)[END_REF][START_REF] Roffi | ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: Task Force for the Management of Acute Coronary Syndromes in Patients Presenting without Persistent ST-Segment Elevation of the European Society of Cardiology (ESC)[END_REF]. The implantation of fewer drug-eluting stents may be explained, in part, by the desire to shorten the duration of dual antiplatelet therapy by using bare-metal stents for patients at high risk of haemorrhage. Of note, the current recommendations are moving to preferential use of drug-eluting stents instead of bare-metal stents, with tailored used of the duration of dual antiplatelet therapy [START_REF] Ibanez | ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation: The Task Force for the management of acute myocardial infarction in patients presenting with ST-segment elevation of the European Society of Cardiology (ESC)[END_REF].

Another important aspect when dealing with older patients is to reduce the side-effectsparticularly the bleeding risk -of invasive procedures and antithrombotic agents. The frequency of major bleeding was reported to be 5% and 6% among patients aged > 85 years in the GRACE and CRUSADE studies, respectively [START_REF] Petroni | Primary percutaneous coronary intervention for ST elevation myocardial infarction in nonagenarians[END_REF][START_REF] Ariza-Sole | Efficacy of bleeding risk scores in elderly patients with acute coronary syndromes[END_REF]. A similar result was found in our study, with no significant difference between octogenarians and nonagenarians. Vascular bleedings may have been limited in the present cohort by the infrequent use of the femoral approach to perform the coronary angiogram, a higher rate of radial access being reported here (92.1%) than in other cohorts (60%) [START_REF] Petroni | Primary percutaneous coronary intervention for ST elevation myocardial infarction in nonagenarians[END_REF].

Study limitations

The major limitation of the present study is the selection bias related to ICU admission, which underlines that the population studied probably excluded patients with poor general health and cognitive status, who would have been treated non-invasively outside the ICU. This hypothesis is supported by previous reports demonstrating a lower admission to ICU for patients aged > 80 years compared with younger patients [START_REF] Husted | Ticagrelor versus clopidogrel in elderly patients with acute coronary syndromes: a substudy from the prospective randomized PLATelet inhibition and patient Outcomes (PLATO) trial[END_REF], and that selected older patients had a higher functional status score and a lower prevalence of frailty compared with those not admitted to an ICU [START_REF] Lorente | Criteria for admitting elderly patients with acute coronary syndrome to critical care units from Spanish hospital emergency departments: a LONGEVO-SCA cohort study[END_REF]. However, this selection bias may be observed in clinical trials including older patients as well.

Conclusions

Provided that nonagenarians are deemed in sufficiently good condition to be admitted to an ICU, their prognosis is not so far removed from that of octogenarians, and could possibly be improved by optimizing treatment. This does not account for the overall prognosis of nonagenarians, who frequently combine cardiac problems with many other comorbidities and frailty.

  Abbreviations: ACS, acute coronary syndromes; ACE, angiotensin-converting enzyme; ARB, angiotensin receptor blocker; BARC, Bleeding Academic Research Consortium; DDD, defined daily dose; GRACE, Global Registry of Acute Coronary Events; ICU, intensive care unit; LVEF, left ventricular ejection fraction; MRA, mineralocorticoid receptor antagonist; NSTEMI, non-ST-segment elevation myocardial infarction; PCI, percutaneous coronary intervention; STEMI, ST-segment elevation myocardial infarction.

Figure 1 .

 1 Figure 1. Study flowchart. ACS: acute coronary syndrome; NSTEMI: non-ST-segment elevation myocardial infarction; STEMI: ST-segment elevation myocardial infarction.

Figure 2 .

 2 Figure 2. Therapeutic management of different subgroups of patients with type 1 non-ST-segment elevation myocardial infarction or ST-segment elevation myocardial infarction (n = 403). A. According to medical cardiac treatment. B. According to defined daily dose. C. According to antithrombotic and anticoagulant treatment. D. According to invasive procedure. ACEi: angiotensin-converting enzyme inhibitor; ARB: angiotensin receptor blocker; BMS: bare-metal stent; DES: drug-eluting stent; LMWH: low-molecular-weight heparin; MRA: mineralocorticoid receptor antagonist; PCI: percutaneous coronary intervention; UFH: unfractionated heparin.

Figure 3 .

 3 Figure 3. Frequency of haemorrhages, according to age and bleeding subtype. BARC: Bleeding Academic Research Consortium.

Figure 4 .

 4 Figure 4. Survival rates. A. All-cause mortality according to age. B. Cardiovascular mortality according to age. C. All-cause mortality according to acute coronary syndrome subtype. D. Cardiovascular mortality according to acute coronary syndrome subtype. NSTEMI: non-ST-segment elevation myocardial infarction; STEMI: ST-segment elevation myocardial infarction.

Table 1

 1 Baseline characteristics of patients in the whole cohort and according to age subgroups after exclusion of type 2 non-ST-segment elevation myocardial infarction.

		All	80-89 years	≥ 90 years	P
		(n = 403)	(n = 311)	(n = 92)
	General characteristics
	Age (years)	86.4 ± 4.3	84.6 ± 2.9	92.6 ± 2.2
	Men/women	43.2/56.8	44.4/55.6	39.1/60.9	0.37
	BMI (kg/m²)	25.0 ± 5.8	25.3 ± 6.2	22.7 ± 3.0	0.043
	Resident in a nursing home	13.4	10.9	22.6	0.005
	Clinical characteristics at admission
	Type of ACS				0.043
	STEMI	36.7	34.1	45.7
	NSTEMI type 1	63.3	65.9	54.3
	SBP (mmHg)	128 ± 27	128 ± 27	125 ± 28	0.30
	DBP (mmHg)	66 ± 16	66 ± 15	66 ± 19	0.98
	Heart rate (bpm)	79 ± 19	78 ± 18	81 ± 18	0.24
	Killip I/II/III/IV	57.3/20.8/16.1/5.8 58.2/18.0/17.0/6.8 54.3/30.4/13.0/2.2 0.033
	Cardiac arrest	5.5	6.4	2.2	0.12
	Laboratory/imaging characteristics
	Number of diseased vessels				0.35
	Unknown	2.2	1.6	4.3
	One-vessel disease	30.0	28.6	34.8
	Two-vessel disease	27.0	27.3	26.1
	Three-vessel disease	40.7	42.4	34.8
	LVEF (%)	47.0 ± 12.4	47.2 ± 12.7	46.3 ± 11.3	0.56
	Significant valvular heart disease 2.1	2.1	2.3	0.92
	eGFR MDRD (mL/min/1.73m²)	65.3 ± 28.0	66.5 ± 28.1	62.5 ± 28.1	0.22
	Haemoglobin (g/L)	124 ± 18	124 ± 19	125 ± 18	0.54
	GRACE score	193 ± 40	192 ± 42	200 ± 37	0.12

Table 2

 2 Treatment according to age subgroups after exclusion of type 2 non-ST-segment elevation myocardial infarction.

		All	80-89 years	≥ 90 years	P
		(n = 403)	(n = 311)	(n = 92)
	Antiplatelets
	Aspirin	385 (95.5)	293 (94.2)	92 (100.0)	0.018
	Clopidogrel	247 (61.3)	177 (56.9)	70 (76.1)	0.001
	Ticagrelor	130 (32.3)	109 (35.0)	21 (22.8)	0.028
	Prasugrel	9 (0.2)	9 (0.3)	0 (0)	0.59
	Glycoprotein IIb/IIIa inhibitor 4 (1.0)	4 (1.3)	0 (0)	0.27
	Anticoagulants
	UFH	55 (13.6)	53 (17.0)	2 (2.2)	< 0.001
	LMWH	164 (40.7)	128 (41.2)	36 (39.1)	0.73
	Fondaparinux	34 (8.4)	22 (7.1)	12 (13.0)	0.070
	VKA	59 (14.6)	49 (15.8)	10 (10.9)	0.24
	NOAC	12 (3.0)	10 (3.2)	2 (2.2)	0.61
	Medical treatment
	ACE inhibitor	241 (59.8)	181 (58.2)	60 (65.2)	0.22
	ARB	45 (11.2)	39 (12.5)	6 (6.5)	0.11
	ACE inhibitor or ARB	286 (71.0)	220 (70.7)	66 (71.7)	0.85
	ACE inhibitor or ARB DDD	0.42 ± 0.28	0.45 ± 0.30	0.32 ± 0.19	0.001
	Beta-blocker	320 (79.4)	242 (77.8)	78 (84.8)	0.15
	Beta-blocker DDD	0.42 ± 0.26	0.44 ± 0.26	0.34 ± 0.21	0.002
	MRA	55 (13.6)	43 (13.8)	12 (13.0)	0.85
	MRA DDD	0.58 ± 0.24	0.60 ± 0.25	0.48 ± 0.21	0.14
	Statin	290 (72.0)	228 (73.3)	62 (67.4)	0.27
	Statin DDD	0.59 ± 0.32	0.62 ± 0.32	0.46 ± 0.29	< 0.001
	Loop diuretic	207 (51.4)	156 (50.2)	51 (55.5)	0.47
	Inotrope	41 (10.2)	32 (10.3)	9 (9.8)	0.89

enzyme; ARB: angiotensin receptor blocker; BMS: bare-metal stent; DDD: defined daily dose; DES: drug-eluting stent; LMWH: low-molecular-weight heparin; MRA: mineralocorticoid receptor antagonist; NOAC: non-vitamin K antagonist oral anticoagulant; PCI: percutaneous coronary intervention; UFH: unfractionated heparin; VKA: vitamin K antagonist.

Acknowledgements

We thank Véréna Landel and Philip Robinson (Direction de la Recherche Clinique et de l'Innovation, Hospices Civils de Lyon) for thorough editing of this article.

Sources of funding

None.

Disclosure of interest