The Future of Exercise-Based Cardiac Rehabilitation for Patients With Heart Failure

Cardiac rehabilitation (CR) is a comprehensive program that includes exercise training, titration of medical therapy, lifestyle modification, educational support, and psychosocial assessment. All these components are safe and beneficial resulting in significant improvements in quality of life, functional capacity, mortality, and hospital readmission. Current guidelines support its use in a broad spectrum of cardiac disease. This review focuses on exercise-based CR for heart failure (HF) patients in whom CR is a recommended treatment. Exercise should be prescribed according to a personalized approach, optimizing, and tailoring the rehabilitative program to the patient's characteristics. Specific CR programs are dedicated to older patients, those with HF and preserved ejection fraction, and recipients of cardiac implantable electronic devices or left ventricular assistance device. Telemedicine may increase CR participation and overcome some of the barriers that limit its utilization.

Complications of Minimally Invasive Left Ventricular Assistance Device Implantation

Indication of Ventricular assistance is advanced cardiac failure with maximal medical and surgical treatment has been used. The ventricular assistance has two main purposes: first, to maintain circulation by discharging the ventricle (s) untill to recovery, or to ensure patient survival by replacing cardiac function permanently or transitionally for patients waiting for heart Transplantation. The encouraging results of the partial or total artificial heart and the miniaturization of these devices allow their use in permanent implantation for patients with heart failure that is not eligible for heart transplantation. In left mono-ventricular assistance, blood is taken from the apex of the left ventricle (LV) and reinjected in the ascending aorta. The classic surgical approach is a total median sternotomy. Other minimally invasive approaches for the implantation or explanation of left ventricular assist devices have been published and have shown encouraging results. These alternatives currently play an important role in certain indications and in patients with heavy medical history. Nevertheless, the complications of the ventricular assistance even by minimally invasive approaches might be serious and represent a turning point in the life of the patients. In this chapter, we describe the implantation technique of left ventricular assistance device (LVAD) and we discuss its advantages and disadvantages including possible complications.

Clinical trials in cardiac xenotransplantation: are we ready to handle ethical issues?

Heart allotransplantation has become one of the methods of choice in the treatment of severe heart failure. In the face of its difficulties, such as the unmet balance between organ supply and demand, the use of xenotransplantation might be an attractive option in the near future, even more with the ongoing progress achieved regarding the avoidance of hyperacute rejection and primary organ disfunction, maintenance of xenograft function and control of xenograft growth. To make possible this translational challenge, some points must be taken into account indeed, and they are the equipoise of human benefit and animal suffering, the risk of unknown infections, a well prepared informed consent, ethical and religious beliefs, and the role of cardiac xenotransplantation in a ventricular assistance device era.

Numerical study of shear-based hemolysis in aorta with left ventricular assistance device

Ventricular assistance devices (VADs) for heart failure treatment have been paid high attention among researchers for decades. However, the follow-up complications such as hemolysis and thrombosis require further optimization for this technique. Shear stress has been demonstrated to be significantly related to the hemolysis because of the rupture of red blood cells membrane with a leaking of hemoglobin in the plasma. This issue has already been investigated inside the pump of VAD, but estimations are still lacking regarding hemolysis generation in the aorta itself after VAD implantaion. Thus, the present study aims to evaluate the hemolysis in aorta through establishing the 3D numerical model of aorta with left ventricular assistance device (LVAD). Non-Newtonian Carreau model has been adopted. Comparisons of hemolysis evaluation have been made with two different mathematical models existing in literature. Moreover, the flow topology and hemodynamic variations have been studied. Different working conditions of LVAD have been considered corresponding to different heart failure severities. The results reveal a relatively low level of hemolysis risks in aorta. The thrombosis is more prone to occur in the case of severe heart failure condition.

Performance characteristics of the new Eurosets magnetically suspended centrifugal pump

Objective: The aim was to evaluate the performance of a newly developed magnetically suspended centrifugal pump head intended for use as a ventricular assistance device with a newly developed extracorporeal membrane oxygenator setup. Methods: In an experimental setup, an extracorporeal membrane oxygenator circuit was established in three calves with a mean weight of 68.2 ± 2.0 kg. A magnetically levitated centrifugal pump was tested, along with a newly designed extracorporeal membrane oxygenator console, at three different flow ranges: (a) 0.0 to 5.2 L/min, (b) 0.0 to 7.1 L/min, and (c) 0.0 to 6.0 L/min. For each setup, the animals were supported by a circuit for 6 h. Blood samples were collected just before caridiopulmonary bypass (CPB) after 10 min on bypass and after 1, 2, 5, and 6 h of perfusion for hemolysis determination and biochemical tests. Values were recorded for blood pressure, mean flow, and pump rotational speed. Analysis of variance was used for repeated measurements. Results: Mean pump flows achieved during the three 6 h pump runs for the three pump heads studied were as follows: (a) flow range 0.0 to 5.2 L/min, 3.6 ± 1.5 L/min, (b) flow range 0.0 to 7.1 L/min, 4.9 ± 1.3 L/min, and (c) flow range 0.0 to 6.0 L/min, 3.8 ± 1.5 L/min. Blood trauma, evaluated by plasma hemoglobin and lactate dehydrogenase levels, did not help in detecting any significant hemolysis. Thrombocytes and white blood cell count profiles showed no significant differences between the groups at the end of the 6 h perfusion. At the end of testing, no clot deposition was found in the oxygenator, and there was no evidence of peripheral emboli. Conclusion: The results suggest that the newly developed magnetically suspended centrifugal pump head provides satisfactory hydrodynamic performance in an acute perfusion scenario without increasing hemolysis.