Evolutionary Improvements in the Jarvik 2000 Left Ventricular Assist Device

The Jarvik 2000 Left Ventricular Assist Device: Results of the United States Bridge to Transplant Trial

The Jarvik 2000 bridge to transplant investigational device exemption study was a multicentered, prospective study of 150 UNOS status I patients implanted with the Jarvik 2000 between 2005 and 2012. During the study period, there were numerous modifications of the system that included converting from pin to cone bearings. Results were analyzed for three cohorts: total (n = 150), pin (n = 128), and cone (n = 22). Baseline demographics included age (52 ± 13), gender (79% male), size (BSA 1.98), and etiology (37% idiopathic dilated cardiomyopathy; 43% Ischemic). Seventy percent of patients were either INTERMACS 1 or 2. The primary endpoint-defined as successful transplantation or listing at 180 days (prespecified at 65%; 95% lower CI: 57%)-was successfully achieved for the total cohort (67.3%; 95% CI: 59.5%-74.3%; p = 0.006). In subgroup analysis of the more contemporary, cone-bearing group, the primary endpoint was met in 91% (95% CI: 72%-97.5%; p = 0.001). Compared with pin patients, cone-bearing patients had less hemolysis as well as decreased end-organ dysfunction. Functional and quality of life scores improved after implantation independent type of bearing. In conclusion, despite a particularly sick patient population, the Jarvik 2000 was shown to be effective in supporting the advanced HF patient.

The path to a hemocompatible cardiovascular implant: Advances and challenges of current endothelialization strategies

Cardiovascular (CV) implants are still associated with thrombogenicity due to insufficient hemocompatibility. Endothelialization of their luminal surface is a promising strategy to increase their hemocompatibility. In this review, we provide a collection of research studies and review articles aiming to summarize the recent efforts on surface modifications of CV implants, including stents, grafts, valves, and ventricular assist devises. We focus in particular on the implementation of micrometer or nanoscale surface modifications, physical characteristics of known biomaterials (such as wetness and stiffness), and surface morphological features (such as gratings, fibers, pores, and pits). We also review how biomechanical signals originating from the endothelial cell for surface interaction can be directed by topography engineering approaches toward the survival of the endothelium and its long-term adaptation. Finally, we summarize the regulatory and economic challenges that may prevent clinical implementation of endothelialized CV implants.

Technology and Technique for left ventricular assist device optimization: A Bi-Tech solution

BACKGROUND

We investigated the synergistic effect of the new cone-bearing design of Jarvik 2000 (Jarvik Heart Inc., NY) together with a minimally-invasive approach on outcomes of LVAD patients.

METHODS

We retrospectively reviewed all patients from 5 institutions involved in the Jarvik 2000 Italian Registry, from October-2008 to October-2016. Patients were divided into three groups according to pump design and implantation technique: pin-bearing design and conventional approach (Group 1); cone-bearing and conventional approach (Group 2); cone-bearing and minimally-invasive implantation (Group 3).

RESULTS

A total of 150 adult patients with end-stage heart failure were enrolled: 26 subjects in Group 1, 74 in Group 2, and 50 in Group 3. Nineteen patients (73%) in Group 1, 51 (69%) in Group 2, and 36 (72%) in Group 3 were discharged. During follow-up, 22 patients underwent transplantation, while in 3 patients the LVAD was explanted. Overall 1-year survival was 58±10%, 64±6% and 74%±7% in Group 1, 2 and 3, respectively (p=0.034). The competing-risks-adjusted cumulative incidence rate for adverse events was 42.1 [27-62.7] per 100 patient-years in Group 1, 35.4 [25.3-48.2] in Group 2, and 22.1 [12.4-36.4] in Group 3 (p=0.046 for Group 1 vs 3).

CONCLUSIONS

The association of the modern cone-bearing configuration of Jarvik 2000 and minimally-invasive surgery improved survival and minimized the risk for cardiovascular events, as a result of combining technology and technique.

Self-care in Adults With a Retro-auricular Left Ventricular Assist Device: An Interpretive Description

Having a retro-auricular left ventricular assist device (LVAD) requires patients to learn specific self-care behaviors, with a considerable burden; the present study aimed at exploring and describing the experience of self-care in this population. An Interpretive Description was conducted, informing the analysis with the Middle-Range Theory of Self-care of Chronic Illness. A purposeful sample of ten people with a retro-auricular LVAD participated in in-depth, semi-structured interviews. Four themes were identified: Innovations and Limitations in Daily Life, Problems Detection, Response to Problems, and Learning Process. All of these were deeply influenced by a cross-cutting theme: Support System. People with a retro-auricular LVAD have self-care needs different from those of people with heart failure or with the abdominal version of the device, and there is a great need for targeted intervention that could be developed in consideration of our findings.

Performance of the Jarvik 2000 left ventricular assist device on mid-term hemodynamics and exercise capacity

The hemodynamic and exercise capacity performance of the Jarvik 2000 left ventricular assist device (LVAD), which is generally used in patients with small body size and relatively preserved cardiac function, is not well understood. We retrospectively examined 18 patients implanted with the Jarvik 2000 LVAD. Pump rotation speed was optimized by the hemodynamic ramp test one year after implantation based on the criteria of mean pulmonary capillary wedge pressure (PCWP) < 18 mmHg, mean right atrial pressure (RAP) < 12 mmHg, and cardiac index (CI) > 2.2 L/min/m² as well as echocardiographic parameters. Exercise capacity was assessed by cardiopulmonary exercise test in an optimized setting. To investigate the impacts of larger body surface area (BSA) and extremely impaired pre-implantation cardiac function on hemodynamics and exercise capacity, two correlation analyses based on BSA and original CI were performed. At a pump speed of 9500 ± 707 rpm, the mean pulmonary artery pressure, PCWP, RAP, and CI were 17 ± 5 mmHg, 9 ± 5 mmHg, 6 ± 4 mmHg, and 2.82 ± 0.54 L/min/m², respectively. Only one patient failed to achieve the hemodynamic criteria. The peak VO₂ and VE/VCO₂ slope were 12.9 ± 3.1 mL/min/kg and 37.7 ± 15.0, respectively. There was an inverse correlation between original CI and heart rate (r = -0.60, p  =  0.01), and a weak correlation between BSA and PCWP (r  =  0.43, p  =  0.08). Based on this study, the overall performance of the Jarvik 2000 device was acceptable, and the patients' body size and original cardiac function had minimum effect on the performance of this device.

Implantable ventricular assistance systems (VAD) as a bridge to transplant or as 'destination therapy'

Heart failure is a complex clinical syndrome associated with a high mortality and morbidity rate. Despite the extensive pharmacological armamentarium, a non-negligible percentage of patients develop advanced heart failure and require further therapies. In these circumstances, heart transplantation remains the treatment of choice, but the limited number of donors and the reduction of potential candidates have made necessary to develop new technologies. Since the 1980s, left ventricular assist devices (LVADs) have been introduced and have completely revolutionized the landscape of advanced heart failure treatments. This article has identified the categories of patients who can benefit from the implantation of an LVAD and summarized the new classifications. In addition, the main LVADs are described, analysing the results of the main clinical studies, with particular reference to adverse events. Although there is no perfect LVAD, a multidisciplinary team approach, dedicated to the treatment of advanced heart failure, can guide the choices on the best device to implant, in order to minimize complications and improve the patient’s quality of life.

Durable Continuous-Flow Mechanical Circulatory Support: State of the Art

Implantable mechanical circulatory support (MCS) systems for ventricular assist device (VAD) therapy have emerged as an important strategy due to a shortage of donor organs for heart transplantation. A growing number of patients are receiving permanent assist devices, while fewer are undergoing heart transplantation (Htx). Continuous-flow (CF) pumps, as devices that can be permanently implanted, show promise for the treatment of both young and old patients with heart failure (HF). Further improvement of these devices will decrease adverse events, enable pulse modulation of continuous blood flow, and improve automatic remote monitoring. Ease of use for patients could also be improved. We herein report on the current state of the art regarding implantable CF pumps for use as MCS systems in the treatment of advanced refractory HF.

Adults Living With a Retro-auricular Left Ventricular Assist Device as Destination Therapy: An Interpretive Description

BACKGROUND

Increasingly, there is a trend toward the use of left ventricular assist devices (LVADs) for treating advanced heart failure, as both bridge-to-transplant therapy and destination therapy. Living with an LVAD profoundly influences patients' lives. Only a few study authors investigated the experience of people with abdominal LVADs, and nothing is known about the unique experience of those with retro-auricular LVADs.

OBJECTIVE

The aim of this study was to explore and describe experiences and lifestyle adjustments in adults with retro-auricular LVADs implanted as destination therapy.

METHODS

Interpretive description methodology was used to explore the experiences of a purposeful sample of 10 individuals with retro-auricular LVADs implanted as destination therapy. Data were collected using in-depth semistructured interviews. Data collection and analysis were simultaneous. Triangulation, journaling, and the "thoughtful clinician test" were used to increase trustworthiness of the findings.

RESULTS

Three primary themes describing the experience of people with retro-auricular LVADs were developed: "a new life," "self-care," and "resilience"; in addition, a crosscutting theme was identified: "support system." This article focuses on the theme "a new life," described as a continuum of events. Individuals with advanced heart failure struggle with symptom burden and consider the implantation of the device as the final option to delay death; then, they wait for the surgery that represents a turning point, after which they begin to recover through a process of adjustment until they reach a new normality.

CONCLUSIONS

Living with a retro-auricular LVAD impacts every aspect of people's lives. Knowing their experiences can help clinicians to develop targeted interventions and offer tailored support.