Jasmin S. Hanke

First implantation in man of a new magnetically levitated left ventricular assist device (HeartMate III).

Outcomes of heart failure patients supported by a continuous-flow left ventricular assist device (LVAD) have steadily improved during the past decade, largely due to better patient selection and management. Nevertheless, adverse events, such as bleeding, infection, stroke, and thrombus, persist and limit the overall effectiveness of this therapy. Bleeding is the most common serious adverse event that results from the extensive surgery required for implantation and blood component damage due to shear forces in the small blood flow paths of current design axialflow and centrifugal-flow pumps. Excessive bleeding results in reoperations, intensive care time, and total hospital stay, which greatly increases a patient’s exposure for infection. The current clinically used pumps create levels of shear force that can activate platelets and damage von Willebrand factor, causing a disruption in the coagulation system that can manifest as thrombosis or gastrointestinal bleeding. The HeartMate III LVAD (Thoratec Corp, Pleasanton, CA) is a new compact intrapericardial centrifugal-flow pump with a full magnetically levitated rotor (Figure 1). The design differs from currently used devices due to actively controlled rotation and levitation of the rotor allowing gaps in the blood flow that are 10 to 20 times wider, which may minimize blood component trauma and result in more stable coagulation. The HeartMate III is now under clinical investigation, and we present here a case report of the first implantation of the device to support a patient with severe heart failure. The patient is a 55-year-old man with the diagnosis of dilated cardiomyopathy and a recent history of multiple hospital admissions due to worsening heart failure symptoms. With multiple medications, the mean arterial blood pressure was 70 mm Hg, cardiac index was 2.1 liters/min/m, and the left ventricular ejection fraction was 10% to 15%. He was classified as Interagency Registry for Mechanically Assisted Circulatory Support Profile 3. After meeting the HeartMate III Conformite Europeene Mark Study inclusion criteria, the patient gave informed consent, and the implantation was performed by Dr. Schmitto and his team at Hannover Medical School, Hanover, Germany on June 25, 2014. After a median sternotomy, the pericardium was only partially opened to help protect right heart function yet allowing access to the vena cava and aorta for cardiopulmonary bypass cannulation. Once full cardiopulmonary bypass was started, the pericardium was fully opened, the heart was elevated, and the myocardium was cored with the HeartMate coring knife approximately 1 cm medial to the left ventricular apex. The sewing cuff was attached around the apical opening with 2-0 Ethibond pledgeted sutures. The inflow conduit was inserted into the left ventricle, and the device was quickly secured to the heart with a locking mechanism. The outflow graft was trimmed for length and anastomosed to the ascending aorta. The percutaneous lead (driveline) was externalized with a doubletunnel technique and exited through the right upper quadrant of the abdominal wall. Cardiopulmonary bypass lasted 59 minutes, and the total operative time was 149 minutes.

Minimally Invasive Off-Pump Left Ventricular Assist Device Exchange: Anterolateral Thoracotomy

The new generation of left ventricular assist devices has enabled minimally invasive surgical procedures. Herein we present a novel technique of left ventricular assist device exchange through a left-sided anterolateral thoracotomy.

Minimally-invasive LVAD Implantation: State of the Art

Nowadays, the worldwide number of left ventricular assist devices (LVADs) being implanted per year is higher than the number of cardiac transplantations. The rapid developments in the field of mechanical support are characterized by continuous miniaturization and enhanced performance of the pumps, providing increased device durability and a prolonged survival of the patients. The miniaturization process enabled minimally-invasive implantation methods, which are associated with generally benefitting the overall outcome of patients. Therefore, these new implantation strategies are considered the novel state of the art in LVAD surgery. In this paper we provide a comprehensive review on the existing literature on minimally-invasive techniques with an emphasis on the different implantation approaches and their individual surgical challenges.

Minimally Invasive Ventricular Assist Device Surgery

The use of mechanical circulatory support to treat patients with congestive heart failure has grown enormously, recently surpassing the number of annual heart transplants worldwide. The current generation of left ventricular assist devices (LVADs), as compared with older devices, is characterized by improved technologies and reduced size. The result is that minimally invasive surgery is now possible for the implantation, explantation, and exchange of LVADs. Minimally invasive procedures improve surgical outcome; for example, they lower the rates of operative complications (such as bleeding or wound infection). The miniaturization of LVADs will continue, so that minimally invasive techniques will be used for most implantations in the future. In this article, we summarize and describe minimally invasive state-of-the-art implantation techniques, with a focus on the most common LVAD systems in adults.

Minimally Invasive Left Ventricular Assist Device Explantation After Cardiac Recovery: Surgical Technical Considerations

The new generation of left ventricular assist devices (LVADs) has enabled minimally invasive surgical procedures for implantation. Herein we present two alternative approaches for minimally invasive LVAD explantation following cardiac recovery, avoiding a sternotomy and improving patient safety.

First series of mechanical circulatory support in non-compaction cardiomyopathy: Is LVAD implantation a safe alternative?

BACKGROUND Left ventricular non-compaction (LVNC) is a rare cardiac disorder characterized by prominent trabeculae and deep recesses of the ventricular myocardium. Patients with LVNC may develop severe congestive heart failure refractory to medical therapy. However, heart transplantation is strongly limited due to donor organ shortage. Thus mechanical circulatory support by left ventricular assist devices (LVADs) is a promising alternative. Nevertheless, hypertrabeculation and proarrhythmogenic potential in LVNC might represent important hurdles for success of LVAD therapy in these patients. METHODS AND RESULTS We retrospectively analyzed the data of a total of 5 patients (3 HVAD, Heartware®; 2 HeartMate II, Thoratec®) with LVNC who underwent LVAD implantation in our institution between 2010 and 2014. Mean follow-up time was 86.5weeks. 30-day survival was 100% without major intrahospital complications. During follow-up, 3 patients developed pump thrombosis requiring pump replacement. Arrhythmias were not detected during follow-up as assessed by ICD interrogation. CONCLUSIONS LVAD implantation in LVNC can be performed with low intrahospital complication rates. However, we observed a high incidence of pump thrombosis during follow-up, possibly related to thromboembolic predisposition by the underlying LVNC. Therefore, careful management of anticoagulation appears to be critical in these patients.

First experiences with HeartMate 3 follow-up and adverse events

Background: The novel HeartMate 3 (HM3) left ventricular assist device (LVAD) received its CE mark in October 2015. It is a new compact LVAD featuring fully magnetically levitated pump, artificial pulse, large pump gaps, and a modular driveline. Here, we present outcomes and adverse events of a single‐center cohort 6 months after HM3 implantation. Methods: We retrospectively studied a patient cohort of 27 patients who were supported with the HM3 at a single institution. We excluded patients with biventricular assist devices and other types of assist devices as well as LVAD exchange and re‐operative procedures. Results: Twenty‐seven patients were enrolled into the study. Within 1 year after HM3 implantation, 1 patient received a heart transplant and 3 patients died. Thirty‐day survival was 88.9% and 6 months 85.2%. No pump thrombosis and no strokes were observed within 6 months. Right heart failure was diagnosed in 1 patient after HM3 implantation (3.7%). No technical complications of the pump were documented. No pump exchanges were necessary. Conclusions: The novel LVAD HM3 has already shown good CE mark trial results. Within this first report after the CE mark trial, the 6‐month survival after HM3 implantation was 85.2%. The HM3 showed excellent midterm results with 0% stroke and 0% pump thrombosis rates 6 months after implantation.

Single-centre experience with the frozen elephant trunk technique in 251 patients over 15 years

OBJECTIVES Our goal was to present our 15-year experience (2001-2015) with the frozen elephant trunk (FET) technique. METHODS A total of 251 patients (82 with aortic aneurysms, 96 with acute aortic dissection type A, 4 with acute type B dissections, 52 with chronic aortic dissection type A, 17 with chronic type B dissection and 67 redo cases) underwent FET implantation with either the custom-made Chavan-Haverich (n = 66), the Jotec E-vita (n = 31) or the Vascutek Thoraflex hybrid (n = 154) prosthesis. The cases were assigned to an early period (2001-2011) and a contemporary period (2012-present). RESULTS Mean cardiopulmonary bypass time, aortic cross-clamp time, circulatory arrest time and selective antegrade cerebral perfusion time were 241 ± 72, 125 ± 59, 56 ± 30 and 81 ± 34 min, respectively. Incidence of rethoracotomy for bleeding, stroke, spinal cord injury, prolonged ventilatory support (>96 h) and long-term dialysis were 18, 14, 2, 24 and 2%, respectively. The in-hospital mortality rate was 11% (in acute aortic dissection type A, 12%). Of the 2 patients with graft infections, 1 died and the other had a protracted hospital stay. There were 49 second-stage procedures in the downstream aorta: either open surgical [n = 25 (thoraco-abdominal, n = 15; descending, n = 6; infrarenal, n = 4)] or transfemoral endovascular (n = 23). Elective thoracic endovascular aneurysm repair R implantation was successful in all 23 cases. CONCLUSIONS FET results are comparable with those of the published results of the conventional elephant trunk technique. FET is an ideal landing zone for subsequent transfemoral endovascular completion. Patients with graft infections may have dismal results.

Left Ventricular Assist Device Implantation With Outflow Graft Tunneling Through the Transverse Sinus

Impairment of coronary artery flow, in either acute or chronic conditions, is a severe complication of transcatheter aortic valve (TAV) implantation, which can arise due to improper TAV positioning. However, little work has been done to quantify the effects of the TAV positioning on the coronary flow. In this study, a realistic in vitro model of coronary artery flow was developed and used to investigate the impact of TAV deployed orientations on coronary flow. The coronary hemodynamics was first replicated mathematically using a lumped parameter model with time-varying myocardial resistance. Based on the analytical model, two stepper motor controlled stopcock valves were integrated in a left heart simulator to represent the variable myocardial resistance in the experimental setup. The coronary flow and pressure waveforms obtained from the in vitro system were consistent with published data. With a TAV deployed in different orientations, the measured results demonstrated that TAV orientation does not have a significant impact on the coronary flow. The developed in vitro model can be further utilized to simulate coronary flow under various pathological conditions.

Left Ventricular Assist Device Therapy for Destination Therapy: Is Less Invasive Surgery a Safe Alternative?

INTRODUCTION AND OBJECTIVES The number of older patients with congestive heart failure has dramatically increased. Because of stagnating cardiac transplantation, there is a need for an alternative therapy, which would solve the problem of insufficient donor organ supply. Left ventricular assist devices (LVADs) have recently become more commonly used as destination therapy (DT). Assuming that older patients show a higher risk-profile for LVAD surgery, it is expected that the increasing use of less invasive surgery (LIS) LVAD implantation will improve postoperative outcomes. Thus, this study aimed to assess the outcomes of LIS-LVAD implantation in DT patients. METHODS We performed a prospective analysis of 2-year outcomes in 46 consecutive end-stage heart failure patients older than 60 years, who underwent LVAD implantation (HVAD, HeartWare) for DT in our institution between 2011 and 2013. The patients were divided into 2 groups according to the surgical implantation technique: LIS (n = 20) vs conventional (n = 26). RESULTS There was no statistically significant difference in 2-year survival rates between the 2 groups, but the LIS group showed a tendency to improved patient outcome in 85.0% vs 69.2% (P = .302). Moreover, the incidence of postoperative bleeding was minor in LIS patients (0% in the LIS group vs 26.9% in the conventional surgery group, P < .05), who also showed lower rates of postoperative extended inotropic support (15.0% in the LIS group vs 46.2% in the conventional surgery group, P < .05). CONCLUSIONS Our data indicate that DT patients with LIS-LVAD implantation showed a lower incidence of postoperative bleeding, a reduced need for inotropic support, and a tendency to lower mortality compared with patients treated with the conventional surgical technique.