Hyperadhesive von Willebrand Factor Promotes Extracellular Vesicle-Induced Angiogenesis: Implication for LVAD-Induced Bleeding.

Bleeding associated with left ventricular assist device (LVAD) implantation has been attributed to the loss of large von Willebrand factor (VWF) multimers to excessive cleavage by ADAMTS-13, but this mechanism is not fully supported by the current evidence. We analyzed VWF reactivity in longitudinal samples from LVAD patients and studied normal VWF and platelets exposed to high shear stress to show that VWF became hyperadhesive in LVAD patients to induce platelet microvesiculation. Platelet microvesicles activated endothelial cells, induced vascular permeability, and promoted angiogenesis in a VWF-dependent manner. Our findings suggest that LVAD-driven high shear stress primarily activates VWF, rather than inducing cleavage in the majority of patients.

Left Ventricular Assist Device Support and Longitudinal Sleeve Gastrectomy Combined With Diet in Bridge to Heart Transplant.

Combining left ventricular assist device (LVAD) implantation and longitudinal sleeve gastrectomy may enable patients with morbid obesity to lose enough weight for heart transplant eligibility. In a retrospective study, we evaluated long-term outcomes of patients with body mass indexes ≥35 who underwent LVAD implantation and longitudinal sleeve gastrectomy during the same hospitalization (from January 2013 through July 2018) and then adhered to a dietary protocol. We included 22 patients (mean age, 49.9 ± 12.5 yr; mean preoperative body mass index, 43.3 ± 6.2). Eighteen months after gastrectomy, all 22 patients were alive, and 16 (73%) achieved a body mass index of less than 35. Myocardial recovery in 2 patients enabled LVAD removal. As of October 2020, 10 patients (45.5%) had undergone heart transplantation, 5 (22.3%) were waitlisted, 5 (22.3%) still had a body mass index ≥35, and 2 (9%) had died. With LVAD support, longitudinal sleeve gastrectomy, and dietary protocols, most of our patients with morbid obesity and advanced heart failure lost enough weight for transplant eligibility. Support from physicians and dietitians can maximize positive results in these patients.

Regression of severe heart failure after combined left ventricular assist device placement and sleeve gastrectomy.

Patients who suffer morbid obesity and heart failure (HF) present unique challenges. Two cases are described where concomitant use of laparoscopic sleeve gastrectomy (LSG) and left ventricular assist device (LVAD) placement enabled myocardial recovery and weight loss resulting in explantation. A 29-year-old male patient with a body mass index (BMI) of 59 kg/m2 and severe HF with a left ventricular ejection fraction (LVEF) of 20-25% underwent concomitant LSG and LVAD placement. Sixteen months after surgery, his BMI was reduced to 34 kg/m2 and his LVEF improved to 50-55%. A second 41-year-old male patient with a BMI of 44.8 kg/m2 with severe HF underwent the same procedures. Twenty-four months later, his BMI was 31.1 kg/m2 and his LVEF was 50-55%. In both cases, the LVAD was successfully explanted and patients remain asymptomatic. HF teams should consult and collaborate with bariatric experts to determine if LSG may improve the outcomes of their HF patients.

Risk of pump thrombosis and stroke in patients with continuous-flow left ventricular assist devices and gastrointestinal bleeding.

Gastrointestinal (GI) bleeding is a common complication following the placement of continuous-flow left ventricular assist devices (LVADs) in patients with advanced heart failure. Secondary events arising as a result of GI bleeding have not been well-described. Furthermore, attribution of these events to bleeding is complicated by the interruption or de-intensification of antithrombotic therapy, while bleeding is controlled. The purpose of this study was to assess the incidence of pump thrombosis and ischemic stroke in patients with LVADs who experience GI bleeding, while on support. This was a single-center, retrospective, observational cohort study of consecutive patients with LVADs implanted from January 2012 to June 2018. Patients were assigned to comparator groups based on whether they experienced GI bleeding while on LVAD support. The primary endpoint assessed was the composite of pump thrombosis or ischemic stroke. Secondary endpoints assessed included incidence of pump thrombosis or ischemic stroke. A total of 250 patients were included after screening for exclusion criteria, 101 (40.4%) in the GI bleeding group, and 149 (59.6%) in the non-bleeding group. The incidence of pump thrombosis or ischemic stroke was not significantly greater in patients experiencing GI bleeding [23 (22.8%) vs. 21 (14.1%); P = .09]; however, the incidence of ischemic stroke alone was significantly greater [17 (16.8%) vs. 10 (6.7%); P = .01]. We conclude that GI bleeding in LVAD patients may be associated with a greater risk of ischemic stroke.

Total Artificial Heart Salvage of a Heterotopic Heart Transplant Patient.

Rescuing heterotopic heart transplantation (HHT) patients remains a challenge in the field. When a 41-year-old patient was transferred to our service, we chose a novel approach that is reported herein. The HHT had been performed over 20 years ago, and in 2016, because of complications, the patient was listed for transplant with a 1A status. For the first time, the SynCardia 50cc total artificial heart (TAH) (SynCardia Systems, LLC, Tucson, AZ) was used in an HHT patient. Investigators attained approval to use the SynCardia 50cc investigational device, as this was an emergent case with few options. The donor heart from the HHT was left in place, alongside the TAH. By leaving the donor heart from the HHT, the need for long and tedious extensive dissection around the right lung was eliminated; thereby reducing the potential risk of lung parenchymal injury, massive bleeding, and complex air leaks. The procedure was successful, and the patient underwent a successful orthotopic heart transplantation six months after being placed on TAH.

Management of Aortic Insufficiency Using Transcatheter Aortic Valve Replacement in Patients with Left Ventricular Assist Device Support.

Left ventricular assist devices (LVADs) increase survival of patients with heart failure. However, long-term LVAD usage can result in aortic insufficiency (AI), thereby compromising LVAD efficiency. Transcatheter aortic valve replacement (TAVR) is an alternative for patients with high risk for surgical valve replacement. We present three cases that developed moderate to severe AI while on HeartMate II (Abbott Laboratories, Chicago, IL) LVAD support; hence, TAVR procedure was performed. Patients A and B (74 year old and 38 year old) developed severe AI and patient C (67 year old) developed moderate AI with cardiogenic shock, after 368, 1,288, and 342 days on LVAD support, respectively. Their aortic valve annulus sizes were 24.2, 24.6, and 23.3 mm, respectively. Oversized Edwards SAPIEN 3 valves (Edwards, Lifesciences, Irvine, CA) were implanted via a transfemoral approach. The patients were hemodynamically stable after the procedure with mild AI in patient A and no AI in patients B and C. Patients were all discharged to home. Follow-up in patients A and C have resulted in long-term (> 2 years) survival and patient B died 616 days after the procedure due to unrelated complications. Transcatheter aortic valve replacement may be an alternative way to manage AI in LVAD patients. Larger studies are needed to evaluate the long-term efficacy of this approach.

Obesity Is Associated with Driveline Infection of Left Ventricular Assist Devices.

In patients with left ventricular assist devices (LVADs), the association of driveline infection (DLI) and body mass index (BMI) remains controversial. The aim of this study was to explore a potential correlation between BMI and DLI in the LVAD patient population. A retrospective, single-center study evaluated patients who underwent LVAD implantation between May 2012 and July 2016. Driveline infection was evaluated per Interagency Registry for Mechanically Assisted Circulatory Support established criteria. Of 222 included patients, 80% were male, the average age was 55 years, and the main underlying heart failure diagnosis was nonischemic cardiomyopathy (56%). The majority of patients (65%) received LVAD as destination therapy and 35% as a bridge to transplantation. Average time-to-first DLI was 296 days after LVAD implantation. In comparison to non-DLI group (80%, N = 177), patients in DLI group (20%, N = 45) had a higher BMI (33.5 ± 8.3 kg/m in DLI group vs. 28.8 ± 7.5 kg/m in non-DLI group, p = 0.0003) and were younger (51 ± 12 years in DLI group vs. 56 ± 12 years in non-DLI group, p = 0.013). There was a significant correlation between BMI and DLI (p < 0.0001), and age was negatively correlated with DLI (p = 0.01). Analysis revealed no correlation between time-to-first DLI and BMI. Our data confirm that higher BMI is associated with increased prevalence of DLI in LVAD population, particularly in younger patients. Addressing excessive body weight in this patient cohort may significantly reduce DLI and thereby improve long-term outcomes.