Transcutaneous Energy Transfer System for Cardiac Assist Devices by Use of Inhomogeneous Biocompatible Core Material

This manuscript was published at 08.10.2021 by the <a href="https://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=20">IEEE Transactions on Magnetics</a>. <div><br><div>Regarding Mr. Sivo's Email, the accepted version of the manuscript is now uploaded which also includes the corresponding DOI.</div></div>

Mock circulatory loops used for testing cardiac assist devices: A review of computational and experimental models

Heart failure is a major health risk, and with limited availability of donor organs, there is an increasing need for developing cardiac assist devices (CADs). Mock circulatory loops (MCL) are an important in-vitro test platform for CAD’s performance assessment and optimisation. The MCL is a lumped parameter model constructed out of hydraulic and mechanical components aiming to simulate the native cardiovascular system (CVS) as closely as possible. Further development merged MCLs and numerical circulatory models to improve flexibility and accuracy of the system; commonly known as hybrid MCLs. A total of 128 MCLs were identified in a literature research until 25 September 2020. It was found that the complexity of the MCLs rose over the years, recent MCLs are not only capable of mimicking the healthy and pathological conditions, but also implemented cerebral, renal and coronary circulations and autoregulatory responses. Moreover, the development of anatomical models made flow visualisation studies possible. Mechanical MCLs showed excellent controllability and repeatability, however, often the CVS was overly simplified or lacked autoregulatory responses. In numerical MCLs the CVS is represented with a higher order of lumped parameters compared to mechanical test rigs, however, complex physiological aspects are often simplified. In hybrid MCLs complex physiological aspects are implemented in the hydraulic part of the system, whilst the numerical model represents parts of the CVS that are too difficult to represent by mechanical components per se. This review aims to describe the advances, limitations and future directions of the three types of MCLs.

Carotid Doppler Ultrasound: Beyond Stenosis

Carotid Doppler ultrasound is frequently used to evaluate for stenosis when a patient presents with stroke-like symptoms. This article aims to increase awareness of various sonographic findings associated with less common scenarios encountered when interpreting carotid Doppler examinations, such as aortic stenosis, aortic insufficiency, cardiac assist devices, and carotid-internal jugular fistula. Ultimately, carotid Doppler ultrasound is a useful tool in diagnosis and subsequent management of a multitude of clinical scenarios that may be encountered when interpreting carotid ultrasounds.

Early mechanical cardiopulmonary resuscitation can improve outcomes in patients with non-traumatic cardiac arrest in the emergency department

Objective To compare the outcomes of patients with non-traumatic cardiac arrest (CA) who received early versus late mechanical cardiopulmonary resuscitation (CPR) with the Lund University Cardiac Assist System (LUCAS) device in the emergency department (ED). Methods This was a retrospective observational study in the ED of a single medical center performed from May 2018 to December 2019; 68 patients with CA were eligible. We grouped the patients according to the time to initiating LUCAS use after CA into an early group (≤4 minutes) and late group (>4 minutes). Results The rate of return of spontaneous circulation (ROSC) was higher in the early group vs the late group (69.2% vs 52.4%, respectively). The 4-hour survival rate was significantly higher in the early group vs the late group (83.3% vs 45.5%, respectively), and CPR duration was significantly shorter in the early group (23.3 ± 12.5 vs 31.1 ± 14.8 minutes, respectively). Conclusion Early mechanical CPR can improve the success of achieving ROSC and the 4-hour survival rate in patients with non-traumatic CA in the ED, considering that more benefits were observed in patients who received early vs late LUCAS device therapy.

A Short Commentary Based on our Article Entitled “Capillary Networks for Bio-Artificial Three-Dimensional Tissues Fabricated Using Cell Sheet Based Tissue Engineering”

The development of organ-like tissues is the next major challenge facing regenerative medicine. Organ-like structures have been synthesized on a small scale, but overcoming current problems with cell sourcing and scalability will facilitate the creation of cardiac assist devices and organs for transplantation. A major obstacle to generating Three-Dimensional (3D) tissues is that diffusion is inadequate for the supply of oxygen/nutrients and removal of waste products, which limits the thickness of the structure to about 0.1 mm