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We investigated changes in estimated glomerular filtration rate (eGFR) after left ventricular assist device (LVAD) implant and the impact on long-term outcomes. A retrospective analysis was conducted for 255 patients with LVADs, divided into 2 groups based on preimplant eGFR (<60 or >60 mL/min/1.73 m2) and into 6 grades (grade 1, >90 mL/min/1.73 m2 normal; grade 2, 60-89 mild dysfunction; grade 3, 45-59 moderate; grade 4, 30-44 moderate to severe; grade 5, 15-29 severe; or grade 6, <15 kidney failure). Changes in eGFR and the impact on long-term outcome and survival were analyzed. One-month postimplant eGFR of the total cohort increased from a baseline of 75.19 ± 34.35 to 118.97 ± 67.62 mL/min/1.73 m2 (P <.001). eGRF 4 years postimplant was higher than baseline but not significantly (P =.48). Patients with a preimplant eGFR > 60 followed the same pattern as the entire cohort. The preimplant eGFR < 60 group had a significant increase at 1 month (P <.001), eGFR remained significantly higher than baseline 4 years postimplant (P =.032), and there was a sustained transition to improved distribution of renal function grade after LVAD implant. Post-LVAD implant survival at 1, 3, and 5 years for baseline eGFR > 60 was 76%, 54%, and 48% and for eGFR < 60 was 71%, 60%, and 48%, respectively (P =.92). Patients with a low preimplant eGFR derive benefit from LVAD therapy, with eGFR remaining elevated above preimplant levels. Preimplant renal dysfunction did not impact negatively on long-term morbidity and mortality. [ABSTRACT FROM AUTHOR]

Due to severely limited donor heart availability, durable mechanical circulatory support remains the only treatment option for many patients with end-stage heart failure. However, treatment complexity persists due to its univentricular support modality and continuous contact with blood. We investigated the function and safety of reBEAT (AdjuCor GmbH), a novel, minimal invasive mechanical circulatory support device that completely avoids blood contact and provides pulsatile, biventricular support. For each animal tested, an accurately sized cardiac implant was manufactured from computed tomography scan analyses. The implant consists of a cardiac sleeve with three inflatable cushions, 6 epicardial electrodes and driveline connecting to an electro-pneumatic, extracorporeal portable driver. Continuous epicardial electrocardiogram signal analysis allows for systolic and diastolic synchronization of biventricular mechanical support. In 7 pigs (weight, 50-80 kg), data were analyzed acutely (under beta-blockade, n = 5) and in a 30-day long-term survival model (n = 2). Acquisition of intracardiac pressures and aortic and pulmonary flow data were used to determine left ventricle and right ventricle stroke work and stroke volume, respectively. Each implant was successfully positioned around the ventricles. Automatic algorithm electrocardiogram signal annotations resulted in precise, real-time mechanical support synchronization with each cardiac cycle. Consequently, progressive improvements in cardiac hemodynamic parameters in acute animals were achieved. Long-term survival demonstrated safe device integration, and clear and stable electrocardiogram signal detection over time. The present study demonstrates biventricular cardiac support with reBEAT. Various demonstrated features are essential for realistic translation into the clinical setting, including safe implantation, anatomical fit, safe device–tissue integration, and real-time electrocardiogram synchronized mechanical support, result in effective device function and long-term safety. reBEAT, a novel, biventricular mechanical circulatory support device that avoids blood contact was studied in pigs. Cardiac function parameters (acute, n = 5) of the left ventricle and right ventricle were significantly improved. In addition, chronic survival of 30 days was achieved with correct positioning and normal tissue morphology. [Display omitted] [ABSTRACT FROM AUTHOR]

The most extended technique of heart procurement from donors after circulatory death involves direct procurement and reperfusion in an ex situ normothermic platform using the Organ Care System (TransMedics, Inc, Andover, MA). This report describes a modified technique (at the Harefield Hospital, London, United Kingdom) with rapid donor blood drainage using a cell-saving device and synchronized perfusion on the Organ Care System. [ABSTRACT FROM AUTHOR]

Background A severe shortage of available donor organs has created an impetus to use extended criteria organs for heart transplantation. Although such attempts increase donor organ availability, they may result in an adverse donor-recipient risk profile. The TransMedics Organ Care System (OCS) (TransMedics, Inc, Boston) allows preservation of the donor heart by perfusing the organ at 34°C in a beating state, potentially reducing the detrimental effect of cold storage and providing additional assessment options. We describe a single-center experience with the OCS in high-risk heart transplant procedures. Methods Thirty hearts were preserved using the OCS between February 2013 and January 2014, 26 of which (86.7%) were transplanted. Procedures were classified as high risk based on (1) donor factors, ie, transport time more than 2.5 hours with estimated ischemic time longer than 4 hours, left ventricular ejection fraction (LVEF) less than 50%, left ventricular hypertrophy (LVH), donor cardiac arrest, alcohol/drug abuse, coronary artery disease or (2) recipient factors, ie, mechanical circulatory support or elevated pulmonary vascular resistance (PVR), or both. Results Donor and recipient age was 37 ± 12 years and 43 ± 13 years, respectively. Allograft cold ischemia time was 85 ± 17 minutes and OCS perfusion time was 284 ± 90 minutes. The median intensive care unit stay was 6 days. One death (3.8%) was observed over the follow-up: 257 ± 116 (109–445 days). There was preserved allograft function in 92% of patients, with a mean LVEF of 64% ± 5%. Conclusions Use of the OCS is associated with markedly improved short-term outcomes and transplant activity by allowing use of organs previously not considered suitable for transplantation or selection of higher risk recipients, or both. [ABSTRACT FROM AUTHOR]

Objectives Partial-support left ventricular assist devices (LVADs) represent a novel strategy for heart failure treatment. The Synergy Pocket Micro-pump (HeartWare Inc, Framingham, Mass), the smallest surgically implanted long-term LVAD, provides partial flow up to 4.25 L/min and was primarily designed for "less sick" patients with severe heart failure. This device is implanted minimally invasively without sternotomy or cardiopulmonary bypass. Early implantation in patients with Interagency Registry for Mechanically Assisted Circulatory Support class 4 and higher was shown to be feasible and associated with significantly improved hemodynamics and quality of life. The aim of this study was to present our experience with implementation of long-term partial circulatory support as a bridge to transplantation in patients with more advanced heart failure who were dependent preoperatively on inotropic support or intra-aortic balloon pump. Methods In this observational study, only inotropic or intra-aortic balloon pump-dependent patients with end-stage heart failure were included (n = 12). These patients underwent Synergy device implantation between February 2012 and August 2013. Results The mean preoperative Interagency Registry for Mechanically Assisted Circulatory Support class was 2.17 ± 0.84 (class 1, 25%; class 2, 33%; class 3, 42%). The mean age was 46 ± 15 years, and 33% were female. Preoperatively, 4 patients (33%) had at least 1 previous sternotomy, 3 patients (25%) were supported with a balloon pump, 1 patient (8%) had a previous full-support LVAD, and 4 patients (33%) had cerebrovascular events in the past. After device implantation, there were no right ventricular failures, device-related infections, hemorrhagic strokes, arterial or venous thromboembolisms, or worsenings of aortic and mitral regurgitation observed over the follow-up. The mean follow up was 174 ± 171 days (range, 5-764 days; cumulative, 3199 days). One patient (8%) died, 3 patients (25%) successfully underwent transplantation, 1 device (8%) was explanted after myocardial recovery, and 5 patients (42%) are still on ongoing support. Two patients (17%) were upgraded to a full-support LVAD after 65 days of mean support. A total of 11 of 12 patients (92%) were discharged from the hospital and are presently alive. Left ventricular end-diastolic diameter was significantly reduced 3 months after device implantation. Conclusions Partial LVAD support may be clinically efficacious in inotropic and intra-aortic balloon pump-dependent patients. On the basis of our experience and evidence of previous research, such patients may benefit from minimally invasive access, no need for sternotomy and cardiopulmonary bypass, a short implantation time, an easy exchange if necessary, and a lower risk of subsequent heart transplantation. Because the implantation is performed without sternotomy, device upgrade is feasible with a comparatively low operative risk and good clinical outcome. Our preliminary results show that partial-support devices may have the potential to replace full-support LVADs in the near future. [ABSTRACT FROM AUTHOR]

Background Significant aortic regurgitation (AR) after continuous-flow left ventricular assist device (cf-LVAD) placement affects device performance and patient outcomes. This study examined the development of AR and long-term results after implantation of cf-LVADs. Methods The study included all patients with no or less than mild AR who underwent HeartMate II (58 [62%]; Thoratec Corp, Pleasanton, CA) or HeartWare (35 [38%]; HeartWare International, Framingham, MA) implantation at our institute from July 2006 to July 2012. Serial echocardiograms were obtained preoperatively, at 1, 3 and 6 months postoperatively, and then at a minimum of 4-month intervals in patients with longer-term support. Kaplan-Meier estimates for freedom from moderate or greater AR were generated. Logistic regression analysis was used to define independent predictors of AR after cf-LVAD implantation. Results Median duration of LVAD support was 527 days (25 th , 75 th : 289, 907; range, 60 to 2,433 days). Mild AR developed in 48 patients (51.6%) over a median duration of 126 days, with progression to moderate AR in 13 (14%) over 493 days and to severe AR in 2 (2.1%) over 1,231 days. The incidence of mild or greater AR was 43.1% in HeartMate II vs 65.7% in HeartWare recipients ( p = 0.035). Overall freedom from moderate or greater AR was 94.7% ± 2.6% at 1 year, 86.9% ± 4.5% at 2 years, 82.8% ± 5.9% at 3 years, and 31% ± 16.9% at 4 years. Independent predictors of AR were duration of support (odds ratio, 1.002; 95% confidence interval, 1.000 to 1.004; p = 0.017) and a persistently closed aortic valve (odds ratio, 0.193; 95% confidence interval, 0.097 to 0.382; p < 0.001). Conclusions AR is associated with longer cf-LVAD support duration and persistent aortic valve closure. Incidence of moderate or greater AR after cf-LVAD implantation increases significantly after 3 years. The clinical implications of these data may warrant consideration of prophylactic aortic valve replacement at the time of cf-LVAD implantation, particularly with expected longer duration of support and in patients with preexisting AR that is more than mild. [ABSTRACT FROM AUTHOR]

Anatomical variants that affect both the anterior and posterior digastric muscles are well described, and include duplications and variable origin or sites of insertion. Although agenesis or atrophy of the anterior digastric occurs in up to 40% of patients with hemifacial microsomia, to our knowledge, it has been reported only rarely in those without this syndrome. To minimise observer bias and to establish the incidence of anomalies and atrophy of this muscle, a prospective 6-year study was conducted by an experienced consultant radiologist in all patients referred for ultrasound of the head and neck. Unilateral atrophy or absence of the anterior digastric muscle was seen in 3 of 1484 patients (0.2%). All 3 were female, and they had no symptoms or clinical signs related to the finding. One subsequently had a magnetic resonance scan. Non-syndromic absence or atrophy of the anterior digastric muscle is rare, and seems to be a unilateral phenomenon. Recognition of this variant could be important before operations in which it may be used as a landmark, or during procedures in which it is used, for example, for reanimation of a static lip or during reconstruction with a submental island flap. [ABSTRACT FROM AUTHOR]

Objective: Rotary axial flow pumps have several potential advantages and disadvantages over pulsatile pumps. The Jarvik 2000 is distinctive in being intracardiac. We report our experience in 22 patients. Methods: The Jarvik 2000 was implanted in 15 men and 7 women. Mean age was 38.8 (range 23–59) years, preoperative diagnosis was dilated cardiomyopathy in 16, postpartum cardiomyopathy in 3, ischemic heart disease in 2, and chronic allograft failure in 1. Twenty-one patients were in New York Heart Association class IV, and 1 patient was in class III. Nineteen patients were on inotropic support, 6 were supported with an intra-aortic balloon pump, and 2 patients had been salvaged with a Centrimag (Levitronix) ventricular assist device. The median pulmonary vascular resistance was 3 Wood units; median pulmonary capillary wedge pressure was 26.6 mm Hg; and mean Cardiac Index was 1.5 L/min/m2. Results: There were 2 early deaths and 6 late deaths. The average postoperative ventilation time and Intensive Treatment Unit stay was 2.2 and 10 days, respectively. One patient required a right ventricular assist device for short-term support and another for medium-term support. Seven patients were bridged to transplant, 3 had myocardial recovery, and 4 are ongoing. Mean and total duration of support was 280.5 and 6172 days, respectively. Driveline failures were noted in 3, but there were no pump infections or failure. Conclusion: The Jarvik 2000 provides satisfactory intermediate-term results as a bridge to transplant or recovery. It appears to be associated with a low rate of serious driveline or pump infections and technical failure. However, bleeding complications due to the required anticoagulation treatment frequently occurred. [Copyright &y& Elsevier]

We report a 56-year-old who underwent orthotopic heart transplantation following left ventricular assist device bridge to transplantation. His postoperative course was complicated by severe sternal wound infection with Acinetobacter species requiring extensive debridement and reconstruction with a pectoralis major flap. This was followed by a total sternectomy, pectoralis flap debridement, and vacuum-assisted dressing. [Copyright &y& Elsevier]

Precise detection and quantification of white matter hyperintensity (WMH) is of great interest in studies of neurological and vascular disorders. In this work, we propose a novel method for automatic WMH segmentation with both supervised and semi-supervised large margin algorithms provided by the framework. The proposed algorithms optimize a kernel based max-margin objective function which aims to maximize the margin between inliers and outliers. We show that the semi-supervised learning problem can be formulated to learn a classifier and label assignment simultaneously, which can be solved efficiently by an iterative algorithm. The model is learned first via the supervised approach and then fine-tuned on a target image by using the semi-supervised algorithm. We evaluate our method on 88 brain fluid-attenuated inversion recovery (FLAIR) magnetic resonance (MR) images from subjects with vascular disease. Quantitative evaluation of the proposed approach shows that it outperforms other well known methods for WMH segmentation. [ABSTRACT FROM AUTHOR]

Background: Longer term quality of life (QOL) outcome in patients who have had a left ventricular assist device (LVAD) explanted due to myocardial recovery (bridge to recovery, BTR) remains uncertain. This study evaluates the QOL of those patients and compares them to bridge-to-transplant (BTT) and transplanted (Tx) patients. Methods: Anonymized QOL Short Form (SF)-36 questionnaires were sent to a total of 72 patients, including: 14 BTR patients (3.6 ± 1.9 years since LVAD removal); 29 BTT patients (3.3 ± 2.3 years since transplantation); and 29 Tx patients (3.8 ± 0.6 years since transplantation). Results: Questionnaires were returned by 78.6%, 79.3% and 56.7% of patients from the BTR, BTT and Tx groups, respectively. In all but two of the domains of the SF-36 questionnaire, scores were significantly better in the BTR group compared with the BTT and Tx groups. Analysis of the two main dimensions and the total SF-36 score between the three groups showed that: (i) physical health dimension tended to be better in BTR (71.9 ± 21) vs BTT (64.5 ± 23.2) and Tx (41.4 ± 48) groups (p = not statistically significant [NS]); (ii) mental health dimension was better in both BTR (78 ± 16.1) and BTT (71.4 ± 21.1) groups compared with the Tx group (39.4 ± 44, p < 0.05); and (iii) total SF-36 score was significantly higher in the BTR and BTT groups compared with the Tx group (76.8 ± 17.6 and 69 ± 21.1 vs 41.4 ± 48, p = NS). Conclusions: BTR patients appear to have better QOL than both BTT and Tx patients. In addition, BTT patients seem to have a better QOL compared with Tx patients, suggesting that placement of ventricular assist devices could improve the physiologic outcome for transplanted patients. [Copyright &y& Elsevier]

Abstract: A variety of methods by which mechanical circulatory support (MCS) can be provided have been described. However, the haemodynamic benefits of the different methods have not been adequately quantified. The aim of this paper is to compare the haemodynamic effects of six forms of MCS by numerical simulation. Three types of ventricular assist device (VAD) are studied: positive displacement; impeller and a novel reciprocating-valve design. Similarly, three pumping modes are modelled: constant flow; counterpulsation and copulsation. The cardiovascular system is modelled using an approach developed previously, using the concentrated parameter method by considering flow resistance, vessel elasticity and inertial effects of blood in individual conduit segments. The dynamic modelling of displacement and impeller pumps is represented by VAD inlet/outlet flow-rate changes. The dynamics of the reciprocating-valve pump is modelled with a specified displacement profile. Results show that in each simulation, the physiological variables of mean arterial pressure and systemic flow are adequately maintained. Modulation of the impeller pump flow profile produces a small (5mmHg) oscillatory component to arterial pressure, whereas the displacement and reciprocating-valve pumps generate substantial arterial pressure and flow pulsatility. The impeller pump requires the least power input, the reciprocating valve pump slightly more, and the displacement pump the most. The in parallel configuration of the impeller and displacement pump designs with respect to the left ventricle provides near complete unloading and can cause the aortic valve to remain closed throughout the entire cardiac cycle with the attendant risk of aortic valve leaflet fusion following prolonged support. The in series configuration of the reciprocating-valve pump avoids this shortcoming but activation must be carefully synchronized to the cardiac cycle to allow adequate coronary perfusion. The reciprocating-valve pump is associated with haemodynamic advantages and a favourable power consumption. [Copyright &y& Elsevier]

In patients with cardiogenic shock, the global use of percutaneous mechanical circulatory support using the Impella CP device has increased with early data suggesting potential benefits over conservative management. In the current case report we describe a simple technique facilitating percutaneous Impella CP or RP exchange with preservation of transfemoral access, which does not require the use of a 0.035' wire. This technique allows for percutaneous sealing of the 14F arteriotomy using new closure devices avoiding the traditional cut-down. [ABSTRACT FROM AUTHOR]

Abstract: Virtual globes are becoming ubiquitous in the visualization of planetary bodies and Earth specifically. While many of the current virtual globes have proven to be quite useful for remote geologic investigation, they were never designed for the purpose of serving as virtual geologic instruments. Their shortcomings have become more obvious as earth scientists struggle to visualize recently released digital elevation models of very high spatial resolution (0.5–1m2/sample) and extent (>2000km2). We developed Crusta as an alternative virtual globe that allows users to easily visualize their custom imagery and more importantly their custom topography. Crusta represents the globe as a 30-sided polyhedron to avoid distortion of the display, in particular the singularities at the poles characteristic of other projections. This polyhedron defines 30 “base patches,” each being a four-sided region that can be subdivided to an arbitrarily fine grid on the surface of the globe to accommodate input data of arbitrary resolution, from global (BlueMarble) to local (tripod LiDAR), all in the same visualization. We designed Crusta to be dynamic with the shading of the terrain surface computed on-the-fly when a user manipulates his point-of-view. In a similarly interactive fashion the globe''s surface can be exaggerated vertically. The combination of the two effects greatly improves the perception of shape. A convenient pre-processing tool based on the GDAL library facilitates importing a number of data formats into the Crusta-specific multi-scale hierarchies that enable interactive visualization on a range of platforms from laptops to immersive geowalls and caves. The main scientific user community for Crusta is earth scientists, and their needs have been driving the development. [Copyright &y& Elsevier]

Background: Testing of native myocardial function in patients with continuous-flow pumps is challenging as reduction/cessation of the pump could result in regurgitation, although the amount and significance of this regurgitation remains unknown. The aim of this study was to determine the optimal speed at which to assess the native left ventricular (LV) function and the physiologic response to speed reduction. Methods: Fifteen male patients with a HeartMate II (HMII) device were studied prospectively on 46 occasions. Measurements were performed serially at three device speed settings: baseline speed; 6,000 rpm; and either 5,000 rpm (Group A) or 4,000 rpm (Group B). The device''s forward and reverse velocity (Vmax f , Vmax r ), forward and reverse velocity time integral (VTI f , VTI r ) and blood volume (BV) were also measured using Doppler with LV echocardiographic parameters and peripheral hemodynamics. Results: No adverse incidents were reported. Speed reduction to 6,000 rpm resulted in a significant decrease in Vmax f , VTI f and BV. There was no significant difference in either forward or reverse flow with further speed reduction in either group. Speed reduction to <6,000 rpm did not have a significant effect on LV loading. Conclusions: Speed reduction in patients with the HMII device is safe. There was no difference between 6,000 rpm and lower speeds, suggesting that 6,000 rpm is sufficient to assess native myocardial function. The absence of significant retrograde filling suggests that LV loading is a physiologic response to speed reduction at 6,000 rpm. [Copyright &y& Elsevier]

Background: Assessment of myocardial recovery during left ventricular assist device (LVAD) support is difficult to perform both safely and effectively. We developed a test involving short-term interruption of LVAD support with measurements of several hemodynamic and echocardiographic parameters at rest and, whenever possible, after exercise, to investigate inotropic reserve. Methods: After full heparinization, the HeartMate I XVE device was switched off. MAP, heart rate (HR), ejection fraction (EF) and left ventricular dimensions were measured on switching off, after 5, 10 and 15 minutes, and after 6-minute walk (6MW). Results: In total, 207 serial tests were performed on 22 patients. A total of 97.6% of the patients tolerated the tests. Of the 202 tolerated tests, 130 were performed on 16 patients who had their device explanted due to myocardial recovery (recovered group), and 72 on 6 patients who did not recover and were transplanted (non-recovered group). After device discontinuation there was an immediate drop in mean arterial blood pressure (MAP), a rise in HR, a reduction in EF and increases in ventricular dimensions. These changes tended to be more marked in the non-recovered group. After 6MW, the recovered group had a significant rise in HR and EF and a non-significant increase in MAP, whereas, the non-recovered group there was a significant drop in MAP compensated by a rise in HR. The distance walked in the recovered group was significantly higher (544 ± 102 vs 418 ± 109 meters, p < 0.05). MAP, pulse pressure and EF were strong predictive factors for recovery. Conclusions: Acute discontinuation of the device to assess recovery is safe and well tolerated and is followed by specific changes in hemodynamic and echocardiographic parameters. This helps in the assessment of recovery, particularly with regard to findings taken after exercise. [Copyright &y& Elsevier]

Background: Changes in myocardial blood flow (MBF) and coronary flow reserve (CFR) are independent prognostic risk factors in idiopathic dilated cardiomyopathy (DCM). The aim of this study was to assess the impact of left ventricular unloading using left ventricular assist device (LVAD) combination therapy on resting MBF and CFR in patients with end-stage heart disease.Methods: We studied 11 patients with deteriorating end-stage DCM (New York Heart Association Class 4) treated with LVAD support combined with pharmacologic therapy in a recovery program. Absolute MBF was measured using oxygen-15-labeled water (H215O) positron emission tomography (PET) at rest during LVAD support and 15 minutes after the LVAD was switched off. Data were corrected for rate pressure product (RPP) when appropriate. Hyperemic MBF (intravenous adenosine, 140 μg/kg · min) was also measured in 6 patients with the LVAD switched off. CFR was calculated as the ratio MBF adenosine/MBF LVAD off (corrected). Data are expressed as mean ± SD.Results: At 317 ± 193 days after device implantation, resting MBF was 0.95 ± 0.29 (LVAD on) and 1.46 ± 0.62 (LVAD off, corrected) ml/min · g (p = 0.01). MBF (LVAD on) was comparable with that of 11 age- and gender-matched normal controls (1.09 ± 0.22 ml/min · g). CFR in the LVAD group was 1.49 ± 0.99 compared with 3.56 ± 1.42 in normal controls (p < 0.01).Conclusions: During LVAD support, resting MBF (LVAD on) was comparable to MBF in normal controls and increased when the LVAD was switched off. However, CFR was significantly impaired, even though all patients studied showed varying degrees of myocardial recovery. The implications of these findings, particularly in the long term, require further study. [Copyright &y& Elsevier]