Donor substance abuse and heart transplantation outcomes.

Heart failure continues to account for millions of cases and deaths worldwide. Heart transplant is the gold standard for treatment of advanced heart failure. Unfortunately, the supply of donor hearts continues to be limited with the increase in demand for heart transplantation. In this review, we aim to explore the safety and efficacy of using hearts from donors with history of substance use. Despite the theoretical effect of cocaine and alcohol on the cardiovascular system, several studies demonstrate no difference in outcomes (overall survival, graft rejection, graft vasculopathy) when using hearts from patients with history of cocaine and alcohol use. The opioid epidemic has expanded the potential donor pool where the current studies have not shown any adverse outcomes when considering donors with history of opioid use. The currently available evidence would support the use of donor hearts from patients with history of alcohol, cocaine, opioids, and marijuana use. Further studies are needed to evaluate the safety of using donor hearts from patients with history of nicotine use.

Aortic root thrombosis leading to STEMI in a Heartmate 3 patient.

Despite left ventricular assist device (LVAD) therapy becoming established for end-stage heart failure (HF), complications remain. Thromboembolic complications are rare with the newest iteration of LVADs. We managed a case of a continuous-flow LVAD-related thromboembolic event that presented as an acute myocardial infarction. A 64-year-old male who underwent Heartmate III® LVAD implantation had crushing substernal chest pain and ventricular tachycardia with acute anterolateral myocardial infarction on electrocardiogram on post-operative day 9. Echocardiography showed closed aortic valve and mild aortic regurgitation, but CT angiography showed thrombus within the left coronary cusp despite full anticoagulation. Continuous suction of blood from the left ventricle despite pulsatile flow into the ascending aorta resulted in a minimally opening aortic valve and stagnation of blood leading to thrombosis on the coronary cusp. Apart from post-operative ventricular tachycardia and right ventricular failure, he had adequate body size (body surface area 2.13 m2) and no post-operative or coagulopathy which could predispose him to thrombosis. Coronary angiography revealed stable severe three-vessel disease and thrombus in left main and proximal circumflex artery, and he had aspiration thrombectomy, and international normalized ratio target was increased to 3-3.5 with aspirin 325 mg daily. He survived to discharge but died 60 days after LVAD implant with multiple low flow alarms, and cardiac arrest. We review the literature and propose a management algorithm for patients with impaired AV opening and aortic root thrombosis.

BFT-IoMT: A Blockchain-Based Trust Mechanism to Mitigate Sybil Attack Using Fuzzy Logic in the Internet of Medical Things.

Numerous sensitive applications, such as healthcare and medical services, need reliable transmission as a prerequisite for the success of the new age of communications technology. Unfortunately, these systems are highly vulnerable to attacks like Sybil, where many false nodes are created and spread with deceitful intentions. Therefore, these false nodes must be instantly identified and isolated from the network due to security concerns and the sensitivity of data utilized in healthcare applications. Especially for life-threatening diseases like COVID-19, it is crucial to have devices connected to the Internet of Medical Things (IoMT) that can be believed to respond with high reliability and accuracy. Thus, trust-based security offers a safe environment for IoMT applications. This study proposes a blockchain-based fuzzy trust management framework (BFT-IoMT) to detect and isolate Sybil nodes in IoMT networks. The results demonstrate that the proposed BFT-IoMT framework is 25.43% and 12.64%, 12.54% and 6.65%, 37.85% and 19.08%, 17.40% and 8.72%, and 13.04% and 5.05% more efficient and effective in terms of energy consumption, attack detection, trust computation reliability, packet delivery ratio, and throughput, respectively, as compared to the other state-of-the-art frameworks available in the literature.

Handheld Device-Based Indoor Localization with Zero Infrastructure (HDIZI).

The correlations between smartphone sensors, algorithms, and relevant techniques are major components facilitating indoor localization and tracking in the absence of communication and localization standards. A major research gap can be noted in terms of explaining the connections between these components to clarify the impacts and issues of models meant for indoor localization and tracking. In this paper, we comprehensively study the smartphone sensors, algorithms, and techniques that can support indoor localization and tracking without the need for any additional hardware or specific infrastructure. Reviews and comparisons detail the strengths and limitations of each component, following which we propose a handheld-device-based indoor localization with zero infrastructure (HDIZI) approach to connect the abovementioned components in a balanced manner. The sensors are the input source, while the algorithms are used as engines in an optimal manner, in order to produce a robust localizing and tracking model without requiring any further infrastructure. The proposed framework makes indoor and outdoor navigation more user-friendly, and is cost-effective for researchers working with embedded sensors in handheld devices, enabling technologies for Industry 4.0 and beyond. We conducted experiments using data collected from two different sites with five smartphones as an initial work. The data were sampled at 10 Hz for a duration of five seconds at fixed locations; furthermore, data were also collected while moving, allowing for analysis based on user stepping behavior and speed across multiple paths. We leveraged the capabilities of smartphones, through efficient implementation and the optimal integration of algorithms, in order to overcome the inherent limitations. Hence, the proposed HDIZI is expected to outperform approaches proposed in previous studies, helping researchers to deal with sensors for the purposes of indoor navigation-in terms of either positioning or tracking-for use in various fields, such as healthcare, transportation, environmental monitoring, or disaster situations.

LOADng-IoT: An Enhanced Routing Protocol for Internet of Things Applications over Low Power Networks.

The Internet of Things (IoT) is an emerging paradigm that proposes the connection of objects to exchange information in order to reach a common objective. In IoT networks, it is expected that the nodes will exchange data between each other and with external Internet services. However, due to deployment costs, not all the network devices are able to communicate with the Internet directly. Thus, other network nodes should use Internet-connected nodes as a gateway to forward messages to Internet services. Considering the fact that main routing protocols for low-power networks are not able to reach suitable performance in the displayed IoT environment, this work presents an enhancement to the Lightweight On-demand Ad hoc Distance-vector Routing Protocol-Next Generation (LOADng) for IoT scenarios. The proposal, named LOADng-IoT, is based on three improvements that will allow the nodes to find Internet-connected nodes autonomously and dynamically, decreasing the control message overhead required for the route construction, and reducing the loss of data messages directed to the Internet. Based on the performed assessment study, which considered several number of nodes in dense, sparse, and mobility scenarios, the proposed approach is able to present significant results in metrics related to quality-of-service, reliability, and energy efficiency.

MARC: A Novel Framework for Detecting MITM Attacks in eHealthcare BLE Systems.

Real-time and ubiquitous patient monitoring demands the use of wireless data acquisition through resource constrained medical sensors, mostly configured with No-input No-output (NiNo) capabilities. Bluetooth is one of the most popular and widely adopted means of communicating this sensed information to a mobile terminal. However, over simplified implementations of Bluetooth low energy (BLE) protocol in eHealth sector is susceptible to several wireless attacks, in particular the Man-in-the-Middle (MITM) attack. The issue arises due to a lack of mutual authentication and integrity protection between the communicating devices, which may lead to compromise of confidentiality, availability and even the integrity of this safety-critical information. This research paper presents a novel framework named MARC to detect, analyze, and mitigate Bluetooth security flaws while focusing upon MITM attack against NiNo devices. For this purpose, a comprehensive solution has been proposed, which can detect MITM signatures based upon four novel anomaly detection metrics: analyzing Malicious scan requests, Advertisement intervals, RSSI levels, and Cloned node addresses. The proposed solution has been evaluated through practical implementation and demonstration of different attack scenarios, which show promising results concerning accurate and efficient detection of MITM attacks.

A Survey of Authentication Schemes in Telecare Medicine Information Systems.

E-Healthcare is an emerging field that provides mobility to its users. The protected health information of the users are stored at a remote server (Telecare Medical Information System) and can be accessed by the users at anytime. Many authentication protocols have been proposed to ensure the secure authenticated access to the Telecare Medical Information System. These protocols are designed to provide certain properties such as: anonymity, untraceability, unlinkability, privacy, confidentiality, availability and integrity. They also aim to build a key exchange mechanism, which provides security against some attacks such as: identity theft, password guessing, denial of service, impersonation and insider attacks. This paper reviews these proposed authentication protocols and discusses their strengths and weaknesses in terms of ensured security and privacy properties, and computation cost. The schemes are divided in three broad categories of one-factor, two-factor and three-factor authentication schemes. Inter-category and intra-category comparison has been performed for these schemes and based on the derived results we propose future directions and recommendations that can be very helpful to the researchers who work on the design and implementation of authentication protocols.

Cost-Effective Encryption-Based Autonomous Routing Protocol for Efficient and Secure Wireless Sensor Networks.

The deployment of intelligent remote surveillance systems depends on wireless sensor networks (WSNs) composed of various miniature resource-constrained wireless sensor nodes. The development of routing protocols for WSNs is a major challenge because of their severe resource constraints, ad hoc topology and dynamic nature. Among those proposed routing protocols, the biology-inspired self-organized secure autonomous routing protocol (BIOSARP) involves an artificial immune system (AIS) that requires a certain amount of time to build up knowledge of neighboring nodes. The AIS algorithm uses this knowledge to distinguish between self and non-self neighboring nodes. The knowledge-building phase is a critical period in the WSN lifespan and requires active security measures. This paper proposes an enhanced BIOSARP (E-BIOSARP) that incorporates a random key encryption mechanism in a cost-effective manner to provide active security measures in WSNs. A detailed description of E-BIOSARP is presented, followed by an extensive security and performance analysis to demonstrate its efficiency. A scenario with E-BIOSARP is implemented in network simulator 2 (ns-2) and is populated with malicious nodes for analysis. Furthermore, E-BIOSARP is compared with state-of-the-art secure routing protocols in terms of processing time, delivery ratio, energy consumption, and packet overhead. The findings show that the proposed mechanism can efficiently protect WSNs from selective forwarding, brute-force or exhaustive key search, spoofing, eavesdropping, replaying or altering of routing information, cloning, acknowledgment spoofing, HELLO flood attacks, and Sybil attacks.

Mobile-health: A review of current state in 2015.

Health telematics is a growing up issue that is becoming a major improvement on patient lives, especially in elderly, disabled, and chronically ill. In recent years, information and communication technologies improvements, along with mobile Internet, offering anywhere and anytime connectivity, play a key role on modern healthcare solutions. In this context, mobile health (m-Health) delivers healthcare services, overcoming geographical, temporal, and even organizational barriers. M-Health solutions address emerging problems on health services, including, the increasing number of chronic diseases related to lifestyle, high costs of existing national health services, the need to empower patients and families to self-care and handle their own healthcare, and the need to provide direct access to health services, regardless of time and place. Then, this paper presents a comprehensive review of the state of the art on m-Health services and applications. It surveys the most significant research work and presents a deep analysis of the top and novel m-Health services and applications proposed by industry. A discussion considering the European Union and United States approaches addressing the m-Health paradigm and directives already published is also considered. Open and challenging issues on emerging m-Health solutions are proposed for further works.

Energy efficient strategy for throughput improvement in wireless sensor networks.

Network lifetime and throughput are one of the prime concerns while designing routing protocols for wireless sensor networks (WSNs). However, most of the existing schemes are either geared towards prolonging network lifetime or improving throughput. This paper presents an energy efficient routing scheme for throughput improvement in WSN. The proposed scheme exploits multilayer cluster design for energy efficient forwarding node selection, cluster heads rotation and both inter- and intra-cluster routing. To improve throughput, we rotate the role of cluster head among various nodes based on two threshold levels which reduces the number of dropped packets. We conducted simulations in the NS2 simulator to validate the performance of the proposed scheme. Simulation results demonstrate the performance efficiency of the proposed scheme in terms of various metrics compared to similar approaches published in the literature.

Secure smart home architecture for ambient-assisted living using a multimedia Internet of Things based system in smart cities.

Recent advances in smartphones and remote monitoring based on the Internet of Things (IoT) have enabled improved multidimensional intelligent services. The advent of IoT-based wearable and multimedia sensors has prevented millions of mishapsthrough seamless and systematic monitoring. An IoT-based monitoring system is composed of several sensor devices to measure vital signs, fall detection, energy consumption, and visual recognition. As the data collected by the sensors are transmitted to cloud storage through the Internet, data security is a major concern when transmitting data from remote locations. To improve data security and prediction accuracy, in this study, we proposed a smart and secure multimedia IoT monitoring system for smart homes backed up by smart grid supervisory control and data acquisition (SCADA). The proposed system employs state-of-the-art IoT microcontrollers and hardware devices and integrates them in a manner that significantly affects the accuracy and speed of the entire system. Furthermore, the information gathered from IoT is securely transferred through private channels and stored on the cloud, which can be accessed authentically and reliably using an information system built into an IoT application. The output was extensively compared in terms of power consumption and delivery ratio, which were based on the values collected with sequence numbers. The comparative analysis demonstrated that the proposed approach provides increased prediction accuracy and better security. Hence, the proposed powerefficient prototype model monitors the entire smart home environment in real time and serves as an early warning system for critical situations.

Assessing routing strategies for cognitive radio sensor networks.

Interest in the cognitive radio sensor network (CRSN) paradigm has gradually grown among researchers. This concept seeks to fuse the benefits of dynamic spectrum access into the sensor network, making it a potential player in the next generation (NextGen) network, which is characterized by ubiquity. Notwithstanding its massive potential, little research activity has been dedicated to the network layer. By contrast, we find recent research trends focusing on the physical layer, the link layer and the transport layers. The fact that the cross-layer approach is imperative, due to the resource-constrained nature of CRSNs, can make the design of unique solutions non-trivial in this respect. This paper seeks to explore possible design opportunities with wireless sensor networks (WSNs), cognitive radio ad-hoc networks (CRAHNs) and cross-layer considerations for implementing viable CRSN routing solutions. Additionally, a detailed performance evaluation of WSN routing strategies in a cognitive radio environment is performed to expose research gaps. With this work, we intend to lay a foundation for developing CRSN routing solutions and to establish a basis for future work in this area.

Nontechnical Skills for Surgeons as a Framework to Evaluate Cardiopulmonary Bypass Management Skills of Resident Trainees.

BACKGROUND: Nontechnical skills are critical in cardiac surgery but currently there is no formal paradigm to teach these in residency training. We investigated the use of the Nontechnical skills for surgeons (NOTSS) system as a framework to assess and teach nontechnical skills related to cardiopulmonary bypass (CPB) management. METHODS: Single-center retrospective analysis of Integrated and Independent pathway thoracic surgery residents who participated in dedicated nontechnical skills evaluation and training. Two CPB management simulation scenarios were utilized. All residents received a lecture on CPB fundamentals and then individually participated in the first simulation ("Pre-NOTSS"). Immediately following this, nontechnical skills were rated by self-assessment and by a NOTSS trainer. All residents then underwent group NOTSS training followed by the second individual simulation ("Post-NOTSS"). Nontechnical skills were rated as before. NOTSS categories assessed included Situation Awareness, Decision Making, Communication and Teamwork, and Leadership. RESULTS: Nine residents were divided into 2 groups: Junior (n = 4, PGY1-4) and Senior (n = 5, PGY5-8). Pre-NOTSS resident self-ratings were higher for Senior than Junior in the categories of Decision Making, Communication and Teamwork, and Leadership while trainer ratings were similar between the groups. Post-NOTSS, resident self-ratings were higher for Senior than Junior in Situation Awareness and Decision Making while trainer scores were higher for both groups in Communication and Teamwork and Leadership. CONCLUSIONS: The NOTSS framework in conjunction with simulation scenarios provides a practical framework to evaluate and teach nontechnical skills related to CPB management. NOTSS training can lead to improvements in both subjective and objective ratings of nontechnical skills for all PGY levels.

Simultaneous Heart-kidney Transplant With Planned Delayed Implantation of the Kidney Graft After Ex Vivo Perfusion.

BACKGROUND: Simultaneous heart-kidney transplant (SHK) is an established option for patients with severe heart failure and chronic kidney disease. Recent studies in simultaneous liver-kidney transplantation demonstrate favorable outcomes achieved by delaying implantation of the kidney for over 24 h. This report describes a case series of consecutive patients listed for SHK who had planned delayed implantation of the kidney graft. METHODS: This case series represents a retrospective analysis of SHK patients extracted from the transplant database at a single center. RESULTS: There were 7 patients who underwent SHK during the study period. In all cases, kidney grafts were maintained on hypothermic ex vivo pulsatile perfusion for delayed implantation (mean cold ischemia 53 h [range, 31-69]). The first 5 patients had 100% 1-y heart and kidney graft survival with good function. Patient 6 was unstable on extracorporeal membrane oxygenation post-heart transplant. The kidney was implanted at 69 h, and the patient died soon thereafter. Patient 7 was also unstable on extracorporeal membrane oxygenation after heart transplant. The decision was made to implant the kidney into a backup kidney recipient. The heart transplant recipient subsequently died several days later, whereas the kidney was successfully transplanted in the alternate candidate. CONCLUSIONS: This case series highlights the potential utility of delayed kidney implantation in SHK patients. SHK with delayed renal transplant may provide an improved physiologic environment for renal transplant, which may result in improved early renal graft function. Delayed kidney transplant also provides the opportunity to transplant the kidney graft into an alternate candidate.

Don't Break My Heart: A Case Report of Takotsubo Syndrome in a Transplanted Heart.

Cardiogenic shock after heart transplant, could be due to acute rejection, cardiac allograft vasculopathy, or myocarditis. Stress cardiomyopathy (CM) in a denervated transplanted heart is unusual. A 56-year-old man with a history of ischemic heart disease and a seizure disorder underwent orthotropic heart transplant. He had breakthrough seizures posttransplant while on levetiracetam (Keppra) and was admitted for status epilepticus. A transthoracic echocardiogram (TTE) was done for hypotension (BP 90/60). TTE showed a severely reduced left ventricular ejection fraction (LVEF) of 15%, hyperkinetic base, and apical ballooning that are consistent with stress CM. Electrocardiogram with T wave inversion in precordial leads. Troponin was elevated to 1.77. The patient had cardiogenic shock and needed an intra-aortic balloon pump and multiple pressors. He was treated for status epilepticus and the LVEF completely recovered in 1 week. The patient had a normal TTE, coronary angiography, and biopsy with no rejection 8 days before admission. Stress CM was the diagnosis of exclusion, confirmed with a complete recovery of the LVEF. There are only 5 case reports of stress CM after heart transplant, with most presenting 9 to 10 years afterwards. We describe an unusual case of cardiogenic shock from stress CM triggered by status epilepticus in a denervated heart only 1 year posttransplant. The mechanism is elusive, and some hypotheses suggest exaggerated sensitivity to a plasma catecholamine surge from parasympathetic denervation. In a denervated heart, autonomic re-innervation can be seen as early as 1 year posttransplant.

Heart Transplantation in Mustard Patients Bridged With Continuous Flow Systemic Ventricular Assist Device - A Case Report and Review of Literature.

Thirty four-year-old male with history of D-transposition of the great arteries (D-TGA) who underwent Mustard operation at 14 months of age presented in cardiogenic shock secondary to severe systemic right ventricular failure. Catheterization revealed significantly increased pulmonary pressures. Due to the patient's inotrope dependence and prohibitive pulmonary hypertension, he underwent implantation of a Heart Ware HVAD® for systemic RV support. Within 4 months of continuous flow ventricular assist device (VAD) implantation complete normalization of pulmonary vascular resistance (PVR) was achieved. He ultimately underwent orthotopic heart transplantation with favorable outcomes. This is the second report of complete normalization of PVR following VAD implantation into a systemic RV in <4 months. We conducted a thorough literature review to identify Mustard patients that received systemic RV VAD as a bridge to a successful heart transplantation. In this article, we summarize the outcomes and focus on pulmonary hypertension reversibility following VAD implant.

Fulminant myocarditis: COVID or not COVID? Reinfection or co-infection?

We describe a unique case of fulminant myocarditis in a patient with presumed SARS-CoV-2 reinfection. Patient had initial infection 4 months backand had COVID-19 antibody at the time of presentation. Endomyocardial biopsy showed lymphocytic myocarditis, that is usually seen in viral myocarditis. The molecular diagnostic testing of the endomyocardial biopsy for cardiotropic viruses was positive for Parvovirus and negative for SARS-CoV-2. Authors highly suspect co-infection of SARS-CoV-2 and Parvovirus, that possibly triggered the immune cascade resulting in fulminant myocarditis. Patient was hemodynamically unstable with ventricular tachycardia and was supported on VA ECMO and Impella CP. There was impressive recovery of left ventricular function within 48 h, leading to decannulation of VA ECMO in 72 h. This unique case was written by the survivor herself.

Cybersecurity and privacy issues for socially integrated mobile healthcare applications operating in a multi-cloud environment.

Social media has enabled information-sharing across massively large networks of people without spending much financial resources and time that are otherwise required in the print and electronic media. Mobile-based social media applications have overwhelmingly changed the information-sharing perspective. However, with the advent of such applications at an unprecedented scale, the privacy of the information is compromised to a larger extent if breach mitigation is not adequate. Since healthcare applications are also being developed for mobile devices so that they also benefit from the power of social media, cybersecurity privacy concerns for such sensitive applications have become critical. This article discusses the architecture of a typical mobile healthcare application, in which customized privacy levels are defined for the individuals participating in the system. It then elaborates on how the communication across a social network in a multi-cloud environment can be made more secure and private, especially for healthcare applications.