scholarly journals Preliminary Computational Analysis of Three Configurations for an Innovative Ventricular Chamber

Processes ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 1358
Author(s):  
Valentina Candela ◽  
Martina Todesco ◽  
Alberto Visentin ◽  
Giovanni Meneghetti ◽  
Assunta Fabozzo ◽  
...  

(1) Background: shape, dimension, hemodynamics, and hemocompatibility are just a few of the several challenging key points that must be addressed in designing any suitable solution for the ventricular chamber of mechanical circulatory support devices. A preliminary evaluation of different geometries of bellow-like ventricular chambers is herein proposed. The chambers were made with a polycarbonate urethane that is acknowledged to be a hemocompatible polymer. (2) Methods: an explicit dynamic computational analysis was performed. The actuation of the three chambers was simulated without the presence of an internal fluid. Maximum stress and strain values were identified, as well as the most critical regions. Geometric changes were checked during simulated motion to verify that the dimensional constraints were satisfied. (3) Results: one chamber appeared to be the best solution compared to the others, since its dimensional variations were negligible, and effective stresses and strains did not reach critical values. (4) Conclusions: the identification of the best geometric solution will allow proceeding with further experimental studies. Fluid–structure interactions and fatigue analyses were investigated.

2021 ◽  
Vol 32 (4) ◽  
pp. 424-433
Author(s):  
Emalie Petersen

Heart failure is a leading cause of morbidity and mortality in the United States. Treatment of this condition increasingly involves mechanical circulatory support devices. Even with optimal medical therapy and use of simple cardiac devices, heart failure often leads to reduced quality of life and a shortened life span, prompting exploration of more advanced treatment approaches. Left ventricular assist devices constitute an effective alternative to cardiac transplantation. These devices are not without complications, however, and their use requires careful cooperative management by the patient’s cardiology team and primary care provider. Left ventricular assist devices have undergone many technological advancements since they were first introduced, and they will continue to evolve. This article reviews the history of different types of left ventricular assist devices, appropriate patient selection, and common complications in order to increase health professionals’ familiarity with these treatment options.


Author(s):  
Gaurav Girdhar ◽  
Yared Alemu ◽  
Michalis Xenos ◽  
Jawaad Sheriff ◽  
Jolyon Jesty ◽  
...  

Flow past mechanical heart valves (MHV) in mechanical circulatory support devices including total artificial hearts and ventricular assist devices, is primarily implicated in thromboembolism due to non-physiological flow conditions where the elevated stresses and exposure times are sufficiently high to cause platelet activation and thrombus formation. Mitigation of this risk requires lifelong anticoagulation therapy and less thrombogenic MHV designs should therefore be developed by device manufacturers [1].


ASAIO Journal ◽  
1993 ◽  
Vol 39 (3) ◽  
pp. M423-M426 ◽  
Author(s):  
Gregory K. MacLean ◽  
Peter A. Aiken ◽  
William A. Adams ◽  
Tofy Mussivand

2021 ◽  
Vol 8 (08) ◽  
pp. 5578-5583
Author(s):  
Usman Sarwar ◽  
Nikky Bardia ◽  
Amod Amritphale ◽  
Hassan Tahir ◽  
MD Ghulam M.Awan

Statistical data has shown that patients now treated in cardiac catheterization laboratories are older with several comorbidities, including renal failure, diabetes, and heart failure [1]. In past patients who were not suitable candidates for percutaneous coronary intervention due to their numerous comorbidities now seems to be a suitable candidate due to tremendous advancements in the field of interventional cardiology like new stent design and availability of advance mechanical circulatory support devices, i.e., Impella performing PCI on these high-risk patients become a viable option. There are two areas of cardiology in which mechanical circulatory support devices keep evolving: one is high-risk (percutaneous coronary intervention) PCI, and the other is a cardiogenic shock that is refractory to initial pressor support.  In this article, we review evidence base data regarding the use of mechanical circulatory support devices in high-risk percutaneous intervention and cardiogenic shock.


2021 ◽  
pp. 106002802110387
Author(s):  
Long To ◽  
Dana Attar ◽  
Brittany Lines ◽  
Melissa McCarty ◽  
Hassan Nemeh ◽  
...  

Background: Heparin exposure and device-related thrombocytopenia complicate the diagnosis of heparin-induced thrombocytopenia (HIT) in patients receiving mechanical circulatory support (MCS). To improve anticoagulation management for patients with newly implanted MCS devices, incidence of confirmed HIT needs to be further characterized. Objectives: The purpose of this study is to describe the incidence of HIT and clinical utility of the 4Ts score in patients with newly implanted MCS devices. Methods: This is a retrospective analysis of MCS patients receiving unfractionated heparin from 2014 to 2017. The primary end point was incidence of laboratory-confirmed HIT. Strong positive, likely positive, low probability, and negative HIT categories were established based on heparin-induced platelet antibody (HIPA) and serotonin release assay (SRA). Secondary end points include characterization of platelet trends, argatroban use, incidence of HIT among each of the MCS devices, and utility of 4Ts score. Results: A total of 342 patient encounters met inclusion criteria, of which 68 HIPA tests and 25 SRAs were ordered. The incidence of HIT was 0.88% (3/342) and 4.4% (3/68) in patients with suspected HIT. Of the 68 HIPA tests, 3 (4.4%) were considered strong positive and 3 of the 25 SRAs were positive. Median 4Ts score was 4 [2.5-4] and optical density 0.19 [0.11-0.54]. The positive predictive value for the 4Ts score was 0.15 (CI = 0.03-0.46) and negative predictive value, 0.93 (CI = 0.82-0.98). Conclusion and Relevance: HIT occurs infrequently with newly implanted MCS devices. The 4Ts score appears to have a high negative predictive value for ruling out HIT.


Sign in / Sign up

Export Citation Format

Share Document