Time Of Left Ventricular Assist Device Implantation Research Articles

Hemolysis in left ventricular assist device: A retrospective analysis of outcomes

Hemolysis is becoming increasingly recognized as a major complication of left ventricular assist device (LVAD) support. Data regarding risk factors, prevalence, and outcomes are limited. To better define the characteristics and prognosis of hemolysis, we present a retrospective case-control study of LVAD patients in our institution. A detailed record review was conducted of 18 patients supported with the HeartMate II (HMII; Thoratec Corp, Pleasanton, CA) who were diagnosed with hemolysis, and their data were compared with 82 patients who received an LVAD implant during the same period who did not develop hemolysis. Patients were excluded if they did not survive hospitalization at the time of LVAD implantation. The primary end points of this analysis were time to death and time to first hospitalization. Of 100 total patients, 18 HMII patients (18%) were diagnosed with hemolysis. Those with hemolysis were younger, had significantly higher lactate dehydrogenase and bilirubin levels, lower international normalized ratio, and no difference in cannula velocities by transthoracic echocardiography. Patient survival in the hemolysis group was markedly decreased at 1 year (38.9% vs 89.3%, p < 0.001), but no differences in hospitalization (p = 0.57) were observed. Partial to complete thrombosis was noted in all of the pumps at explant. These findings demonstrate that hemolysis is associated with high mortality, likely serving as a marker of pump thrombosis. Elevated lactate dehydrogenase and bilirubin levels are important indicators for hemolysis, and lower international normalized ratio may pre-dispose for this worrisome condition. Diagnosis should prompt clinicians to consider pump exchange or explant, listing for transplantation, or intensifying anti-coagulation.

Cardiovascular Implantable Electronic Device Infections in Left Ventricular Assist Device Recipients

BackgroundMost patients with left ventricular assist devices (LVADs) have concomitant cardiovascular implantable electronic devices (CIEDs). However, clinical presentation and outcome of CIED infection in the setting of LVAD has not been previously described.MethodsWe retrospectively reviewed 247 patients who underwent LVAD implantation at Mayo Clinic campuses in Minnesota, Arizona, and Florida, from January 2005 to December 2011. Demographic and clinical data of patients who met criteria for CIED infection were extracted.ResultsOf 247 patients with LVADs, 215 (87%) had CIED at the time of LVAD implantation and six (2.8%) subsequently developed CIED infections. Three patients developed CIED lead‐related endocarditis and the other three had pocket infection. All three instances of CIED pocket infection were preceded by device generator exchange, whereas all three patients with CIED lead‐related endocarditis had prior LVAD‐related infections. Causative pathogens included Pseudomonas aeruginos (1), coagulase‐negative staphylococci (2), methicillin‐resistant Staphylococcus aureus (1), a gram‐positive bacillus (1), and culture negative (2). All patients underwent complete CIED removal along with antimicrobial therapy. The three patients with CIED lead‐related endocarditis and prior LVAD infections received chronic suppressive antibiotic therapy, and one patient had LVAD exchange. All but one remained alive at the last follow‐up with a median duration of 15 months (7–46 months) from the time of CIED infection.ConclusionPatients who are receiving LVAD therapy and develop CIED infection should be managed with complete CIED removal. Chronic suppressive antibiotic therapy is warranted in cases that have concomitant LVAD infection.

Morphologic changes in the aortic wall media after support with a continuous-flow left ventricular assist device

Continuous-flow left ventricular assist devices (LVADs) provide durable, reliable, energy-efficient long-term support. However, the biologic effects of continuous flow are not completely known. Therefore, we examined aortic wall morphology in patients with heart failure before and after prolonged circulatory support with a continuous-flow LVAD. After applying a partial aortic occlusion vascular clamp in the lower half of the ascending aorta, we removed samples of aortic wall tissue and then attached the outflow graft of the pump. Samples were obtained from 11 patients (9 men and 2 women, mean age 65 ± 7 years) with severe heart failure at the time of LVAD implantation. We obtained matched specimens at explantation after heart transplantation (n = 5) or autopsy (n = 6). These specimens were removed from the distal ascending aorta, remote from the aortic anastomotic site. Tissue sections were stained with hematoxylin and eosin, Movat's pentachrome and Masson's trichrome. Smooth muscle actin immunohistochemistry was performed on all sections. To evaluate the morphology of the aortic wall media, we quantitatively graded tissue sections for medial thickness, medial degenerative changes, smooth muscle cell (SMC) disorientation and depletion, elastic fiber fragmentation and depletion, medial fibrosis and atherosclerotic changes. The mean duration of support was 140 ± 136 days (range 87 to 580 days). The histologic evaluation and comparison of specimens obtained before and after LVAD support showed significantly increased foci of medial degeneration, SMC depletion, elastic fiber fragmentation, medial fibrosis and atherosclerotic changes after LVAD support. Mean medial thickness was not significantly different after LVAD support. We observed similar changes between samples obtained at transplantation and those obtained at autopsy. After continuous-flow LVAD support, the morphology of the aortic wall media was altered in all of our patients. The clinical relevance of these findings is unknown.

Granulomatous myocarditis in severe heart failure patients undergoing implantation of a left ventricular assist device

Granulomatous myocarditis may develop into cardiomyopathy and severe congestive heart failure that requires implantation of a left ventricular assist device (LVAD). Left ventricular (LV) core samples were collected from 177 patients with severe heart failure at the time of LVAD implantation, and samples were histologically examined and graded for severity of hypertrophy and fibrosis. Granulomatous myocarditis incidentally seen in a subset of samples was characterized by staining and culturing for mycobacteria and fungi. Various clinical parameters in these patients were analyzed. Of the 177 LV core samples examined, 6 (3.4%) showed nonnecrotizing granulomatous inflammation in the myocardial wall. Stains and cultures for mycobacteria and fungi were negative. All six patients [three women, three men; five African American, one Asian; mean age, 52±9 years (range, 41-61 years)] had arrhythmias and required an automatic implantable cardioverter defibrillator. Before LVAD implantation, the patients' mean cardiac index was 1.8±0.4 l/min/m(2); cardiac output, 2.9±0.6 l/min; and ejection fraction, 20±2%. One year after LVAD implantation, one patient had undergone heart transplantation. At 2 years, a second patient was transplanted, and one died. At 3 years, a third patient was transplanted and died postoperatively; two patients remained on support. No clinical evidence indicated involvement of other organs or recurrence in the transplanted patients. The incidental diagnosis of granulomatous myocarditis in our patients indicates that histological study of LV core samples in patients who undergo LVAD implantation may contribute to the diagnosis and be a consideration in the management of the underlying cause of heart failure.

Pre-operative echocardiographic features associated with persistent mitral regurgitation after left ventricular assist device implantation

Previous studies have shown remarkable decrease in size of the left ventricle after left ventricular assist device (LVAD) implantation due to mechanical unloading. However, a certain number of patients continue to have significant mitral regurgitation (MR) under LVAD support. We investigated pre-operative echocardiographic features associated with persistent MR after LVAD implantation. We retrospectively reviewed 82 consecutive patients undergoing continuous-flow LVAD implantation between 2007 and 2010. We obtained echocardiograms performed within 2 weeks before and 1 week after surgery. We investigated the pre-operative echocardiographic findings associated with significant MR post-LVAD and compared 1-year mortality after LVAD surgery between patients with and without significant MR post-LVAD. MR was significant in 43 patients (52.4%) before LVAD surgery. Among those, 5 underwent concomitant mitral valve repair (MVr) at the time of LVAD implantation. Of the remaining 38 patients, 25 (65.8%) showed improvement of MR, whereas 13 patients (34.2%) continued to have significant MR post-LVAD. Multivariate analysis revealed that posterior displacement of the coaptation point of mitral leaflets was significantly associated with significant MR post-LVAD (hazard ratio, 1.335; 95% confidence interval, 1.035-1.721; p = 0.026) even after adjusting for the amount of pre-operative MR flow. Post-LVAD 1-year survival of patients with and without significant MR post-LVAD was not significantly different (92.3% vs 89.1%, p = 0.826). Pre-LVAD posterior displacement of mitral leaflets may be indicative of post-operative significant MR, which would help identify echocardiographic features of functional MR refractory to simple volume reduction of the ventricle.

Long-term left ventricular support in patients with a mechanical aortic valve

Objectives. The presence of a mechanical prosthesis has been regarded as an increased risk of thromboembolic complications and as a relative contraindication for a left ventricular assist device (LVAD). Five patients in our center had a mechanical aortic valve at the time of device implantation and were studied regarding thromboembolic complications. Design. Five patients operated upon with an LVAD (1 HeartMate I™, 4 HeartMate II™) between 2002 and 2011 had a mechanical aortic valve at the time of implantation. The first patient had a patch closure of the aortic valve. In four patients, the prosthesis was left in place. Anticoagulants included aspirin, warfarin, and clopidogrel. Results. The average and accumulated treatment times were 150 and 752 days, respectively. Three of the five patients showed early signs of valve thrombosis on echo with concomitant valve dysfunction. Four patients were transplanted without thromboembolic events during pump treatment. One patient died from a hemorrhagic stroke after 90 days on the LVAD. Conclusions. The strategy of leaving a mechanical heart valve in place at the time of LVAD implantation in five patients led to valvular thrombosis in three but did not provoke embolic events. It increased the complexity of postoperative anticoagulation.

Dynamics of Galectin-3 Levels Following Left Ventricular Assist Device Implantation

Purpose Galectin-3 (gal-3) is a novel biomarker implicated in cardiac fibrosis and is shown to correlate with the severity of heart failure (HF) and to independently predict mortality in HF. We investigated if hemodynamic improvement after left ventricular assist device (LVAD) implantation affects gal-3 levels. Methods and Materials Plasma samples were acquired from patients at time of LVAD implantation (HMII or Heartware, n=57), at 3 (n=17) and 6 months post-LVAD (n=14), and at explantation (n=23), as well as from healthy age and gender matched controls (n=30). Gal-3 was measured using a commercially available ELISA assay (BG Medicine, Waltham, MA). Data was analyzed with Prism 5. Events rates were calculated using the Kaplan-Meier method. Results At time of LVAD implantation, HF patients had significantly higher gal-3 levels compared to controls (29.2±14 ng/ml vs. 13±9 ng/ml; p figure 1 ] Conclusions Gal-3 levels are associated with HF state and predict survival on LVAD support. Distinct dynamics in gal-3 levels occur in patients following LVAD implantation with an initial decrease but subsequent increase. Gal-3 may serve as a new biomarker for risk assessment of patients before LVAD implantation.

Micro-RNA-451 and Measures of Hemolysis Associated with Left Ventricular Assist Device Implantation

Purpose Hemolysis is a well-known complication of left ventricular assist device (LVAD) implantation that contributes to hemodynamic derangement and end-organ damage. Micro-RNAs (miRs) are non-coding RNA species that control gene expression by targeting specific messenger RNAs for degradation. MiR-451 is specifically expressed in erythrocyte precursors and mature red blood cells. The goal of this study was to evaluate changes in circulating miR-451 levels before and after LVAD implantation and whether these changes associate with measures of hemolysis. Methods and Materials Blood samples were obtained from healthy volunteers and from patients with advanced heart failure at the time of LVAD implantation and at the time of explantation. Absorbance at 414 nm (ABS 414 ), the maximum absorbance of hemoglobin, was measured in plasma. RNA was extracted from plasma and RT-PCR specific for miR-451 was performed. Results The mean duration of LVAD therapy was 488 ± 179 days. Plasma ABS 414 correlated with the degree of hemolysis of blood that was mechanically disrupted in vitro. The mean plasma ABS 414 was increased 3.4-fold after LVAD implantation compared to paired pre-implantation samples (P=0.05), which had a mean plasma ABS 414 comparable to non-hemolyzed control samples. Lactate dehydrogenase and bilirubin, commonly used tests for hemolysis, each correlated poorly with plasma ABS 414 among these patients (R2=0.20 and 0.22, respectively; each P nonsignificant) and did not differ between pre- and post-LVAD samples. Compared to control plasma, miR-451 levels were roughly 40% higher in samples from heart failure patients before LVAD placement. Plasma miR-451 levels increased 164-fold after LVAD implantation compared to paired pre-implant samples (Mann-Whitney P= 0.002). Conclusions Micro-RNAs hold promise as biomarkers in heart failure. MiR-451 may be a new marker of hemolysis related to LVAD implantation that performs favorably compared to traditional markers.

Percutaneous Transcatheter Closure of the Aortic Valve to Treat Cardiogenic Shock in a Left Ventricular Assist Device Patient With Severe Aortic Insufficiency

In this case report, we present a patient status post left ventricular assist device implantation complicated by de novo aortic insufficiency. At 8 months postimplant, the patient underwent a reoperative aortic valve repair, without complete closure of the valve. Three months after reoperation, the patient developed cardiogenic shock secondary to recurrent, severe aortic insufficiency. Ultimately, the patient underwent percutaneous, transcatheter closure of the aortic valve with an Amplatzer Cribiform device (AGA Medical Corp, Plymouth, MN). Two months post procedure, the patient remains stable with improved symptoms and functional status, and without evidence of further aortic insufficiency or device migration.

Evolution of general surgical problems in patients with left ventricular assist devices

Left ventricular assist devices (LVADs) are increasingly used to treat patients with end-stage heart failure. These patients may develop acute noncardiac surgical problems around the time of LVAD implantation or, as survival continues to improve, chronic surgical problems as ambulatory patients remote from the LVAD implant. Previous reports of noncardiac surgical problems in LVAD patients included patients with older, first-generation devices and do not address newer, second-generation devices. We describe the frequency and management of noncardiac surgical problems encountered during LVAD support with these newer-generation devices to assist noncardiac surgeons involved in the care of patients with LVADs. We retrospectively reviewed the medical records of consecutive patients receiving LVADs at our institution. We collected data for any consultation by noncardiac surgeons within the scope of general surgery during LVAD support and subsequent treatment. Ninety-nine patients received implantable LVADs between 2003 and 2009 (first-generation, n = 19; second-generation, n = 80). Excluding intestinal hemorrhage, general surgical opinions were rendered for 34 patients with 49 problems, mostly in the acute recovery phase after LVAD implantation. Of those, 27 patients underwent 28 operations. Respiratory failure and intra-abdominal pathologies were the most common problems addressed, and LVAD rarely precluded operation. Patients with second-generation LVADs were more likely to survive hospitalization (P = .04) and develop chronic, rather than emergent, surgical problems. Patients with LVADs frequently require consultation from noncardiac surgeons within the scope of general surgeons and often require operation. Patients with second-generation LVADs are more likely to become outpatients and develop more elective surgical problems. Noncardiac surgeons will be increasingly involved in caring for patients with LVADs and should anticipate the problems unique to this patient population.

Liberal use of tricuspid-valve annuloplasty during left-ventricular assist device implantation.

The study aimed to determine whether liberal use of tricuspid-valve repair (TVr) is associated with adverse outcomes. The study was a retrospective review of 51 implantable left-ventricular assist devices (LVADs) performed in a single center between January 2008 and December 2009. TVr using Edwards MC 3 annuloplasty ring was performed if there was either documented moderate or greater tricuspid regurgitation or severe annular dilatation. TVr was performed in 37 patients. One patient was converted to replacement intra-operatively. Compared with patients who did not have TVr, the age was similar (mean 52 vs 50 years, p=0.62), as was frequency of the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) level 1 or 2 (43% vs 50%, p=0.13). Day 1 hemodynamics were also similar: mean central venous pressure (13.5 vs 14 mmHg; p=0.10) and mean pulmonary artery pressure (25 vs 25.6 mmHg; p=0.76), as was Day 1 bilirubin (3.1 vs 3.9 mg dl(-1), p=0.27). Median duration of mechanical ventilation (2 days) and inotropic support (5 days) and rates of bleeding were identical in both groups. Although there was a trend toward longer intensive care unit (ICU) stays in the TVr group (6 vs 5 days; p=0.12), as a group these patients experienced less use of blood-product transfusion and less hospital length of stay. Hospital mortality was similar in both groups (TVr 18.9%, no TVr 21.4%, p=0.7). TVr can be applied during LVAD implantation without 'obvious' increase in perioperative risk. As there are theoretical benefits to eliminating tricuspid regurgitation, our data argue for a more liberal approach to TVr at the time of LVAD implantation.

ORAL PRESENTATION

ORAL PRESENTATION

Stem cells transplantation combined with long-term mechanical circulatory support enhances myocardial viability in end-stage ischemic cardiomyopathy

End-stage ischemic cardiomyopathy (ICM) with non-graftable coronary arteries is a common and debilitating problem. The ultimate therapeutic goal in such cases is cardiac transplantation which is restricted by donor availability. Alternatively, left ventricular assist devices (LVAD) are increasingly used as bridge to transplantation or more recently as destination therapy in non-transplant candidates. Although encouraging results with LVAD as a bridge to recovery have been reported from the Harefield group in patients with non-ischemic heart failure, myocardial recovery after mechanical circulatory support (MCS) rarely occurs in the severely failing ischemic heart [1]. Ischemic cardiomyopathy has the distinctiveness of irreversible myocardial damage with scar tissue formation and mainly impaired perfusion of the remaining viable myocardium. Widely used secondand third-generation continuous-flow LVAD offer symptomatic relief and prolong life. However, LV unloading rarely improves native heart function in ischemic hearts [2]. Because of this we sought after increasing myocardial viability and improving native cardiac function in a patient with end-stage ICM by injecting autologous bone marrow stem cells (BMSC) at the time of LVAD implantation.

Reverse Remodeling With Left Ventricular Assist Devices

Over the last 2 decades, numerous advancements in medical therapies have improved patient outcomes in heart failure (HF). However, a significant number of patients still progress to end-stage HF, in which treatment options are largely limited to cardiac transplantation. As patient demands for transplant continue to exceed the supply of available organs, mechanical assist devices—specifically, the left ventricular assist device (LVAD)—were initially introduced as a bridge to cardiac transplantation. LVADs have 2 important beneficial effects. First, LVADs are placed in parallel to the native left ventricle (LV), causing pressure and volume unloading of the LV. Second, LVADs restore cardiac output and subsequent perfusion to the organs. As a result of these 2 effects, it became evident that some patients had actual improvement in LV function after LVAD placement. The term reverse remodeling was used to describe the improvement in myocardial function that was observed in patients with a seemingly end-stage disease. With reverse remodeling, a new hope for the treatment of HF was born—using LVADs as a bridge to recovery; however, to date, this promise has largely been unrealized. This probably is reflective of the fact that the sequela of mechanical ventricular unloading are quite complex and appear to involve the engagement of competing biological pathways including regression of cardiomyocyte hypertrophy as well as progressive cell atrophy. Although the promise of ventricular recovery still persists, its actualization will await a more comprehensive dissection of these competing biological processes. This review will discuss the beneficial clinical effects of LVAD support as well as review what is known about the cellular and molecular response to mechanical unloading and mechanisms of reverse remodeling. Key research findings have been summarized in the Table. View this table: Table. Summary of Research of LVAD Support on Clinical Effects and the Cellular and Molecular Changes That May Contribute to Reverse …

Tricuspid valve repair with left ventricular assist device implantation: Is it warranted?

Tricuspid regurgitation is common in patients with advanced heart failure. The ideal operative strategy for managing tricuspid valve regurgitation (TR) in patients undergoing left ventricular assist device (LVAD) implantation is unclear. This study was designed to evaluate the effect on outcomes of concomitant tricuspid valve repair (TVR) for moderate to severe (3(+)/4(+)) TR at the time of LVAD implantation. Patients with >3(+) TR who underwent LVAD implantation from 2005 to 2009 were retrospectively evaluated. Pre-, intra- and post-operative data, including hemodynamics, inotrope requirements and end-organ function parameters, were considered. Outcomes of patients receiving TVR were compared with those who did not receive TVR (NTVR). Seventy-two LVADs were implanted during the study period. Forty-two (58%) patients had ≥ 3(+) TR prior to LVAD implantation. Eight patients underwent TVR and 34 patients did not undergo TVR (NTVR). There were no significant differences in baseline characteristics or severity of TR between the two groups. The TVR group had a longer cardiopulmonary bypass time (p < 0.01) and required more blood products (p < 0.05). Higher post-operative creatinine and blood urea nitrogen (BUN) values were noted in the TVR group. One patient in the TVR group and 3 patients in the NTVR group required right-sided mechanical assistance (p = 0.6). There was no significant difference in short- or long-term mortality between the two groups. TVR for ≥ 3(+) TR prolonged operative time and showed similar outcomes compared with LVAD implantation alone. A benefit of performing TVR was not demonstrated. As such, TVR may not be necessary at the time of LVAD implantation.

Cardiac fibrosis and cellular hypertrophy decrease the degree of reverse remodeling and improvement in cardiac function during left ventricular assist

This study investigated if the degree of cardiac fibrosis and myocyte size at the time of left ventricular assist device (LVAD) implantation predicts the degree of improvement in cardiac function and sustained recovery after LVAD explantation. The study included 34 patients who underwent LVAD-off test. LV end-diastolic (LVEDD) and end-systolic diameter (LVESD), LV ejection fraction (LVEF), mean pulmonary artery pressure (mPAP), pulmonary capillary wedge pressure (PCWP), and cardiac index (CI) were measured before LVAD implantation and during LVAD-off test. Myocardial tissue was obtained from the apical core at LVAD implantation. The degree of cardiac fibrosis had significant correlations with changes in LVEDD (r = -0.725, p < 0.0001), LVESD (r = -0.800, p < 0.0001), LVEF (r = -0.637, p < 0.0001), mPAP (r = -0.569, p = 0.0010), PCWP (r = -0.463, p = 0.0123), and CI (r = -0.544, p = 0.0015). Myocyte size also had significant correlations with changes in LVEDD (r = -0.386, p = 0.0235), LVESD (r = -0.414, p = 0.0141), and LVEF (r = -0.528, p = 0.0015). The LVAD was successfully removed in 9 patients. The degree of cardiac fibrosis and myocyte size in these patients was significantly smaller compared with the patients who did not undergo LVAD removal. Cardiac fibrosis and myocyte size at the time of LVAD implantation were significant predictors of degree of improvement of cardiac function and the sustained recovery after the LVAD explantation.

3: Tricuspid Valve Repair at the Time of Left Ventricular Assist Device Implantation: Is It Warranted?

The ideal operative strategy for tricuspid valve regurgitation (TR) in patients (Pts) receiving left ventricular assist device (LVAD) is unclear.Tricuspid valve repair (TVR) has been undertaken with the hypothetical aim of preventing right heart failure.This study was designed to evaluate the effects on outcomes of TVR for moderate to severe (3+/4+) TR at the time of LVAD implantation.

The use of extracorporeal membrane oxygenation in patients with therapy refractory cardiogenic shock as a bridge to implantable left ventricular assist device and perioperative right heart support

Implantation of left ventricular assist device (LVAD) as a bridge to recovery or transplantation is a widely accepted treatment modality. Preexisting organ dysfunction is thought to unfavorably affect patient survival after implantation of a ventricular assist device (VAD). We present our experience using extracorporeal membrane oxygenation (ECMO) in patients with cardiogenic shock to stabilized organ function prior to LVAD implantation. Between September 2006 and March 2008, five patients in cardiogenic shock with preexisting organ dysfunction (impaired liver and kidney function) were supported with ECMO before LVAD implantation. ECMO-LVAD interval was 8 +/- 4 days. All patients were transferred to a LVAD. At the LVAD implantation time, glutamic-oxaloacetic transaminase (GOT) decreased from 206.25 +/- 106.93 Ul (-1) to 70.6 +/- 32.9 U l(-1), glutamic-pyruvic transaminase (GPT) decreased from 333.5 +/- 207.3 U l(-1) to 77.8 +/- 39.7 U l(-1), and creatinine decreased from 2.2 +/- 0.9 mg dl(-1) to 1.2 +/- 0.2 mg dl(-1). One patient died while on LVAD support due to not device related sepsis. One patient received successful heart transplantation. Overall survival was 80%. In all patients, we removed the ECMO 3 days after LVAD implantation. After removal of the ECMO there was no right heart failure. ECMO support can immediately stabilize circulation and provide organ perfusion in patients with cardiogenic shock. After improvement of organ function, LVAD implantation can be performed successfully in this patient collective. To avoid right ventricular failure, the ECMO should not be removed at the time of LVAD implantation, and used as a right ventricular support for the immediate postoperative period.

Human Clinical Fitting Study of the DexAide Right Ventricular Assist Device

The DexAide right ventricular assist device (RVAD) has been developed as an implantable RVAD. The purpose of this study was to determine the final design and optimal anatomical placement of the DexAide RVAD when implanted simultaneously with either of two commercially available left ventricular assist devices (LVADs) in patients. A mock-up DexAide RVAD was used to assess configuration with each of two types of commercially available LVADs at the time of LVAD implantation in three human clinical cases. The pump body of the DexAide RVAD was placed either in the preperitoneal space or in the right thoracic cavity. The DexAide RVAD placed into the right thoracic cavity is suitable for use with the Novacor or HeartMate II LVADs. The results of this study will guide the finalization of the inflow cannula and optimal placement of the DexAide RVAD for human clinical trials.

Hypoxemia after an axial flow pump Jarvik-2000 implantation: Catheter induced

Hypoxemia after an axial flow pump Jarvik-2000 implantation: Catheter induced