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In this article, the problem of generating multimodel state space descriptions in a data-driven context to embed the dynamic behavior of nonlinear systems is addressed. The proposed methodology takes advantage of three ingredients: 1) linear time-invariant system behavior; 2) data-driven modeling; and 3) reinforcement learning (RL) technicalities. These elements are properly combined to develop a data-driven algorithm capable to derive an accurate outer convex approximation of the nonlinear evolution. In particular, an actor-critic RL scheme is designed to efficiently comply with the exhaustive research on the whole parameter space. At each iteration, the effectiveness of the obtained uncertain polytopic model is tested by a probabilistic approach based on a confidence level metrics. As the main merits of the proposed approach are concerned, the following aspect clearly stands up: the development of an interdisciplinary methodology that takes advantage of system theory, probabilistic arguments and RL capabilities giving rise to an harmonized architecture in charge to deal with a vast class of nonlinear systems. Finally, the validity of the proposed approach is tested by resorting to benchmark examples that allow to quantify the level of accuracy of the computed convex hull.

In this paper, platoons of autonomous vehicles operating in urban road networks are considered. From a methodological point of view, the problem of interest consists of formally characterizing vehicle state trajectory tubes by means of routing decisions complying with traffic congestion criteria. To this end, a novel distributed control architecture is conceived by taking advantage of two methodologies: deep reinforcement learning and model predictive control. On one hand, the routing decisions are obtained by using a distributed reinforcement learning algorithm that exploits available traffic data at each road junction. On the other hand, a bank of model predictive controllers is in charge of computing the more adequate control action for each involved vehicle. Such tasks are here combined into a single framework: the deep reinforcement learning output (action) is translated into a set-point to be tracked by the model predictive controller; conversely, the current vehicle position, resulting from the application of the control move, is exploited by the deep reinforcement learning unit for improving its reliability. The main novelty of the proposed solution lies in its hybrid nature: on one hand it fully exploits deep reinforcement learning capabilities for decision-making purposes; on the other hand, time-varying hard constraints are always satisfied during the dynamical platoon evolution imposed by the computed routing decisions. To efficiently evaluate the performance of the proposed control architecture, a co-design procedure, involving the SUMO and MATLAB platforms, is implemented so that complex operating environments can be used, and the information coming from road maps (links, junctions, obstacles, semaphores, etc.) and vehicle state trajectories can be shared and exchanged. Finally by considering as operating scenario a real entire city block and a platoon of eleven vehicles described by double-integrator models, several simulations have been performed with the aim to put in light the main features of the proposed approach. Moreover, it is important to underline that in different operating scenarios the proposed reinforcement learning scheme is capable of significantly reducing traffic congestion phenomena when compared with well-reputed competitors.

In this paper, a sustainable routing algorithm for vehicle platoons operating in smart urban networks is presented. The proposed approach makes use of deep reinforcement learning (DRL) and set-theoretic model predictive control (MPC). In particular, the learning process aims at reducing traffic congestion and $CO_{2}$ emissions, whereas the MPC unit allows to adequately track the assigned path by using real-time traffic data. To adequately analyze the performance of the resulting control architecture, the SUMO and MATLAB environments are used to implement complex operating scenarios where road maps data and vehicle state trajectories can be shared and exchanged. Finally, numerical studies are provided by resorting to the SUMO environment and considering a platoon of five vehicles. The resulting simulation campaign puts in light the capability of the training process to significantly mitigate the $CO_{2}$ emissions of the whole platoon: from a minimum of 3.7 % to a maximum of 13% with respect to the use of the well-known Dijkstra algorithm.

In this article, a state estimate based robust model predictive control strategy is developed for networked cyberphysical systems under false data injections. The core of the proposed approach consists in elaborating an observed based general framework whose main feature relies on its adaptability to different classes of attacks. The main feature of the proposed scheme relies on the capability to mitigate undesired system behaviors due to external malicious actions. This is achieved by showing that an augmented state-estimate/estimation error set-membership conditions allow us to quickly detect data integrity anomalies and, as a consequence, to implement adequate counter-measures. In particular, set-theoretic model predictive arguments are combined with the perturbation analysis and sequential quadratic programming in order to reduce as much as possible the occurrence of refresh procedures on the communication network when resilient command actions are no longer available. As one of its main merits, these arguments allow to remove the constructive assumptions present in very recent competitors. In this respect, the framework is customized for covert attacks by specifying actuation and detection phases and proving feasibility and closed-loop stability properties. The core of the resulting solution exploits output feedback receding horizon and set-theoretic control ideas so that the resilient nature of the virtual control moves is formally put in light.

In this paper, platoons of autonomous vehicles in urban road networks are considered. From a methodological point of view, the problem consists in characterizing vehicle state trajectory tubes by means of routing decisions complying with traffic congestion criteria. To this end, a novel distributed control architecture is conceived by taking advantage of two methodologies: the routing decisions are obtained by using a distributed reinforcement learning algorithm that exploits available traffic data and a bank of model predictive controllers is in charge of computing the more adequate control action for each involved vehicle.

Outcomes after transcatheter aortic valve replacement (TAVR) and infectious diseases may vary according to sex.

Recent clinical and demographical studies on COVID-19 patients have demonstrated that men experience worse outcomes than women. However, in most cases, the data were not stratified according to gender, limiting the understanding of the real impact of gender on outcomes. This study aimed to evaluate the disaggregated in-hospital outcomes and explore the possible interactions between gender and cardiovascular calcifications. Data was derived from the sCORE-COVID-19 registry, an Italian multicentre registry that enrolled COVID-19 patients who had undergone a chest computer tomography scan on admission. A total of 1683 hospitalized patients (mean age 67±14 years) were included. Men had a higher prevalence of cardiovascular comorbidities, a higher pneumonia extension, more coronary calcifications (63% vs.50.9%, p<0.001), and a higher coronary calcium score (391±847 vs. 171±479 mm3, p<0.001). Men experienced a significantly higher mortality rate (24.4% vs. 17%, p=0.001), but the death event tended to occur earlier in women (15±7 vs. 8±7 days, p= 0.07). Non-survivors had a higher coronary, thoracic aorta, and aortic valve calcium score. Female sex, a known independent predictor of a favorable outcome in SARS-CoV2 infection, was not protective in women with a coronary calcification volume greater than 100 mm3. There were significant differences in cardiovascular comorbidities and vascular calcifications between men and women with SARS-CoV2 pneumonia. The differences in outcomes can be at least partially explained by the different cardiovascular profiles. However, women with poor outcomes had the same coronary calcific burden as men. The presumed favorable female sex bias in COVID-19 must therefore be reviewed in the context of comorbidities, especially cardiovascular ones.

The coronary sinus Reducer represents a novel therapeutic option with established safety and clinical benefit in the treatment of patients with refractory angina, possibly achieved by enhancing perfusion of myocardial ischemic territories. We report the first case providing insight on how improved perfusion might translate into improved myocardial function as assessed by cardiac magnetic resonance strain imaging, thus suggesting a physiological rationale to test coronary sinus Reducer in the setting of ischemic cardiomyopathy with reduced ejection fraction and adverse remodelling.

The coronary sinus Reducer is a percutaneous device proven to improve angina symptoms in refractory angina (RA). We evaluated its potential cost-effectiveness and impact on the healthcare resource use.

Coronary access (CA) and percutaneous coronary intervention (PCI) might be challenging after valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) with supra-annular self-expanding valves (SS-TAVs) in surgical aortic valves (SAVs). Our study aim was to compare feasibility, predictors, and techniques of CA and PCI following ViV-TAVR with ACURATE neo2 (Boston Scientific, Marlborough, MA) and Evolut PRO+ (Medtronic, Minneapolis, MN).

Background: Pericardial effusion is frequent in the acute phase of ST-segment elevation myocardial infarction. However, its prognostic role in the era of primary percutaneous coronary intervention is not completely understood.Methods: We investigated the association between pericardial effusion, assessed by transthoracic echocardiography, and survival in a large cohort of ST-segment elevation myocardial infarction patients treated with primary percutaneous coronary intervention, enrolled in the Trieste primary percutaneous coronary intervention registry from January 2007 to March 2017. Multivariable analysis and a propensity score approach were performed.Results: A total of 1732 ST-segment elevation myocardial infarction patients were included. Median follow-up was 45 (interquartile range 19–79) months. Pericardial effusion was present in 246 patients (14.2%). Thirty-day all-cause mortality was similar between patients with and without pericardial effusion (7.8% vs. 5.4%, P=0.15), whereas crude long-term survival was worse in patients with pericardial effusion (26.2% vs. 17.7%, P≤0.01). However, at multivariable analyses the presence of pericardial effusion was not associated with long-term mortality (hazard ratio 1.26, 95% confidence interval 0.86–1.82, P=0.22). Matching based on propensity scores confirmed the lack of association between pericardial effusion and both 30-day (hazard ratio 1, 95% confidence interval 0.42–2.36, P=1) and long-term (hazard ratio 1.14, 95% confidence interval 0.74–1.78, P=0.53) all-cause mortality. Patients with pericardial effusion experienced a higher incidence of free wall rupture (2.8% vs. 0.5%, P<0.0001) independently of the entity of pericardial effusion.Conclusions: In acute ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention, the onset of pericardial effusion after ST-segment elevation myocardial infarction is not independently associated with short and long-term higher mortality. Free wall rupture has to be considered rare compared to the fibrinolytic era and occurs more frequently in patients with pericardial effusion, suggesting a close monitoring of these patients in the early post-primary percutaneous coronary intervention phase.

Transcatheter aortic valve replacement (TAVR) is the gold standard for severe valvular aortic stenosis in patients at high/prohibitive surgical risk. This procedure has also been used in patients with previous mitral valve (MV) prostheses, with contrasting outcomes reported. The aim of this study is to describe procedural and early outcomes of patients with previous MV prostheses undergoing TAVR.

ABSTRACTBackground:Although systematically underestimated in the past, the importance of tricuspid regurgitation (TR) is being progressively recognized. We aimed to evaluate the clinical significance of severe TR from a cohort of patients at a tertiary center.Methods:A retrospective analysis was performed on 6309 consecutive patients undergoing echocardiography between October 2014 and September 2015 in a single center in Milan, Italy. The study endpoints included cardiovascular mortality, major adverse cardiac and cerebrovascular events (MACCE) and net adverse clinical events (NACE).Results:A total of 2336 (37%) patients were found to have TR of any severity, 272 (4.3%) had severe TR, 415 (6.6%) moderate TR, and 1649 (26.1%) mild TR. In the severe TR group, 40 (14.7%) patients suffered cardiovascular death, while 53 (19.5%) and 141 (51.8%) developed MACCE and NACE, respectively. In addition, there were 88 (32.4%) patients with severe TR who were re-hospitalized for cardiovascular-related events. Patients with severe TR were more likely to be in New York Heart Association functional class III–IV (p= 0.022) and on higher doses of loop diuretic (p= 0.022) than those with only moderate TR. Multivariable analysis revealed that blood urea nitrogen (BUN, p= 0.031) and abnormal liver function blood tests (p= 0.010) were independent predictors of mid-term cardiovascular mortality, while BUN and tricuspid annular plane systolic excursion were found to be independent predictors of mid-term NACE.Conclusions:The prevalence of any TR was high in patients undergoing echocardiography at a tertiary referral center, and severe TR was not uncommon and associated with high mid-term morbidity and mortality.

The rePOT technique is a novel and easily applied approach for coronary bifurcations. Drug-Coated Balloon (DCB) angioplasty is increasingly being utilized in management of small vessels and coronary bifurcation lesions. Herein, we propose a new approach for treating coronary bifurcation lesions with the application of DCB to treat the side-branch in addition to the rePOT technique: the POT-sideDCB-POT technique.

A 70-year-old woman was admitted to our hospital for severe tricuspid regurgitation caused by cardioverter-defibrillator lead impingement; treatment with MitraClip system (Abbott Vascular, Santa Clara, CA) was attempted. After realizing the impossibility of grasping in the regurgitant area because of extensive leaflets gap, we implanted a clip in another commissure, even in the absence of regurgitation originating from that area. In this way, we achieved a significant acute valve remodelling, which allowed the subsequent successful deployment of a second clip in the regurgitant area. This proposed dual-staged approach can be considered systematically for the treatment of anatomies generally regarded as unfavourable or unsuitable.

Percutaneous treatment of tricuspid valve regurgitation using MitraClip can be performed safely achieving improvement in reduction of regurgitation. Tricuspid valve shows different anatomic variations, in particular regarding the number of leaflets, which could represent a challenge for transcatheter valve intervention. We present a case of massive tricuspid regurgitation in a 4-leaf clovervalve. We implanted a first MitraClip into the anteroseptal commissure and then a second one between the 2 posterior leaflets, with a successful reduction of residual regurgitation. In conclusion, this approach can be safely performed in a 4-leaflet right ventricular valve.

Transcatheter tricuspid valve intervention is gaining importance due to the development of percutaneous techniques addressing tricuspid regurgitation. The presence of a redundant eustachian valve can increase procedural complexity by restricting the manipulation of transcatheter devices. We present a case of torrential tricuspid regurgitation and a redundant eustachian valve hampering the manipulation of the delivery system. We were able to reach the tricuspid valve by looping 2 standard guidewires into the atrium. We performed a tricuspid-plasty by implanting 2 MitraClips with a satisfactory final result. This technique can be applied when the eustachian valve impairs navigation in the right atrium.

Background: Myocardial reperfusion after primary percutaneous coronary intervention (PCI) can be assessed by the extent of post-procedural ST-segment resolution. The European Ambulance Acute Coronary Syndrome Angiography (EUROMAX) trial compared pre-hospital bivalirudin and pre-hospital heparin or enoxaparin with or without GPIIb/IIIa inhibitors (GPIs) in primary PCI. This nested substudy was performed in centres routinely using pre-hospital GPI in order to compare the impact of randomized treatments on ST-resolution after primary PCI.Methods: Residual cumulative ST-segment deviation on the single one hour post-procedure electrocardiogram (ECG) was assessed by an independent core laboratory and was the primary endpoint. It was calculated that 762 evaluable patients were needed to show non-inferiority (85% power, alpha 2.5%) between randomized treatments.Results: A total of 871 participated with electrocardiographic data available in 824 patients (95%). Residual ST-segment deviation one hour after PCI was 3.8±4.9 mm versus 3.9±5.2 mm for bivalirudin and heparin+GPI, respectively (p=0.0019 for non-inferiority). Overall, there were no differences between randomized treatments in any measures of ST-segment resolution either before or after the index procedure.Conclusions: Pre-hospital treatment with bivalirudin is non-inferior to pre-hospital heparin + GPI with regard to residual ST-segment deviation or ST-segment resolution, reflecting comparable myocardial reperfusion with the two strategies.

Although the rate of procedural complications during transcatheter aortic valve implantation has decreased because of technological advancement and increased operator experience, device embolization remains a rare but potentially fatal complication, even with new generation devices. We report, to our knowledge, the first case of Portico valve (St Jude Medical, Minneapolis, MN) migration despite apparent optimal initial implantation depth, which was retrieved using a novel strategy after failure of a traditional retrieval technique. We also describe a mechanism of left coronary artery systolic perfusion with diastolic backflow, which led to myocardial ischemia.

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The placebo effect is a well described phenomenon in blinded studies evaluating antianginal therapeutics, although its effect on clinical research metrics remains unknown. We conducted a systematic review and meta-analysis to quantify the effect of placebo on end points of symptoms, life quality, and functional outcomes in randomized placebo-controlled trials (RCTs) of symptomatic stable coronary artery disease.

Concomitant severe mitral-tricuspid regurgitation is observed in up to 30% of patients with reduced left ventricular ejection fraction. In symptomatic subjects at high surgical risk, transcatheter treatment is a viable option in the presence of suitable anatomy. We present a case of mitral regurgitation worsening after TriClip (Abbott, Abbott Park, IL) implantation in a patient with a previous successful MitraClip (Abbott) intervention. The correction of tricuspid regurgitation by catheter repair improves overall hemodynamics, but it can sometimes paradoxically worsen mitral regurgitation, as herein displayed. Clinical care is needed to detect tricuspid regurgitation repair-induced worsening of mitral regurgitation and ensure optimal management.

Staphylococcus aureus(S aureus) has been extensively studied as causative microorganism of surgical prosthetic-valve infective endocarditis (IE). However, scarce evidence exists on S aureusIE after transcatheter aortic valve replacement (TAVR).

The rates of in-hospital mortality following percutaneous interventional procedures (PIP) during the COVID-19 pandemic period compared to the non-pandemic period has not been reported so far.

Supplemental Digital Content is available in the text.

Supplemental Digital Content is available in the text.