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Background: Both pulsatile-flow and continuous-flow left ventricular assist devices (LVADs) successfully provide patients a bridge to transplantation. Some data suggest that continuous-flow pumps increase the risk of allograft rejection, contributing to posttransplantation morbidity and mortality. We sought to analyze the relationship between LVAD flow characteristics and subsequent allograft rejection in bridge to transplant (BTT) patients. Methods: Patients with LVADs from the UTAH Transplant Affiliated Hospitals were retrospectively analyzed. Rejection was determined pathologically according to the International Society for Heart and Lung Transplantation revised cardiac allograft rejection scale. Multimodal statistical analyses were applied. Results: Of 1,076 patients who underwent transplantation over a 26-year period, 151 had LVADs. Of these, 111 (77 pulsatile flow, 34 continuous flow) patients had pathologic data available. There was no difference in overall rejection (grades 1R to 3R) between the pulsatile-flow LVAD and continuous-flow LVAD groups (2.00 ± 1.43 versus 1.50 ± 1.16 episodes/year; p = 0.076.) Patients with pulsatile-flow LVADs had more clinically relevant (grades 2R to 3R) rejection than did patients with continuous-flow LVADs (0.49 ± 0.72 versus 0.12 ± 0.33 episodes/year; p < 0.001). There was no survival difference at 1 year (p = 0.920) or 4 years (p = 0.721) after transplantation. Conclusions: Patients with continuous-flow LVADs have similar overall rejection rates and a reduced rate of clinically relevant rejection compared with patients with pulsatile-flow LVADs during the first year after transplantation. Although there is theoretical concern that nonphysiologic, nonpulsatile flow could alter the neurohormonal profile of patients in heart failure, we are encouraged that the type of LVAD circulation does not influence posttransplantation allograft survival. [ABSTRACT FROM AUTHOR]

Objective: Destination therapy experience using long-term left ventricular assist devices was analyzed relative to the benchmark Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure trial to evaluate the potential for improving outcomes with this groundbreaking therapy for advanced heart failure. Methods: The largest single-center experience with destination therapy in the United States (Utah Artificial Heart Program, LDS Hospital, Salt Lake City, UT) was retrospectively analyzed. All destination therapy recipients (n = 23) presented with chronic, advanced heart failure, meeting indications for destination therapy adopted from the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure trial. All received HeartMate left ventricular assist devices (Thoratec Corp, Pleasanton, Calif), with 87% receiving an improved XVE model. Advanced practice guidelines were implemented using a multidisciplinary approach. Survivals (Kaplan–Meier, log-rank analyses) and adverse events (Poisson regression) were compared with those of the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure left ventricular assist device group (n = 68). Results: Survival in the destination therapy group was significantly increased (P = .007), with an overall reduction in mortality of 66%. The 2-year survival was 77% for destination therapy compared with 29% for the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure left ventricular assist device group (P < .0001). The 1-year survival was 77% for destination therapy compared with the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure left ventricular assist device rate of 52% (P = .036). Adverse events decreased by 38% (3.90 per patient-year in the destination therapy group compared with the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure left ventricular assist device rate of 6.32). Factors related to severity of illness met Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure-like criteria for both groups. Conclusions: This analysis provides evidence that long-term destination therapy can be improved well beyond the pioneering experience of the Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure trial. With continued evolution of devices, management, and patient selection, outcomes approaching those of heart transplantation may be possible. [Copyright &y& Elsevier]

Objective: This study compares clinical results of the standard Maze III operation, a highly effective treatment for atrial fibrillation, to less complex variations of the Maze III operation utilizing unipolar and bipolar radiofrequency ablation and pulmonary vein isolation. Methods: Records were reviewed of 377 patients who had operations for treatment of atrial fibrillation at a single institution over a 10-year period. Standard Maze III was performed in 220 patients, unipolar radiofrequency Maze III in 60, bipolar radiofrequency Maze III in 65, and radiofrequency pulmonary vein isolation in 32. Electrocardiograms were obtained at discharge and 3-, 6-, and 12-month intervals. Chi-square test, logistic regression, and Bayesian theory analyses were performed to determine significant associations between operative procedures and outcomes. Results: Mean age was 65.1 years (range 22-87). There were 13 hospital deaths (3.4%) and 16 deaths during follow-up. Most patients (90.2%, 340/377) had concomitant operations. Electrocardiogram analysis was available in 344 patients at 3 months and 313 patients at 6 months. Freedom from atrial fibrillation at 6 months was superior after standard Maze III compared with radiofrequency modifications. Subanalysis according to surgeon experience demonstrated good results regardless of operative experience. Conclusions: This single-institution experience suggests that the standard Maze III operation is superior to radiofrequency operations for treatment of atrial fibrillation. Radiofrequency modifications of the Maze III operation are also effective treatments for atrial fibrillation and can achieve good results regardless of surgeon experience. [Copyright &y& Elsevier]

Background Driveline exit site (DLES) infection is a major complication of ventricular assist devices (VADs). Differences in the sheath material interfacing with exit site tissue appear to affect healing time and infection risk more than site hygiene, but the mechanistic basis for this is not clear. Methods Health record data from Utah Artificial Heart Program patients with HeartMate II (HMII) devices implanted from 2008 to 2012 were retrospectively reviewed, with particular attention to interface type, incorporation (healing) time, and infections. Tissue samples from the DLES were collected at the time of VAD removal in a small subset. These samples were examined by routine histology and environmental scanning electron microscopy (ESEM). Results Among 57 patients with sufficient data, 15 had velour interfaces and 42 had silicone. Indications for and duration of support were similar between the groups. The silicone group had shorter incorporation time (45 ± 22 vs. 56 ± 34 days, P = .17) and fewer DLES infections (20% vs. 1.7%, P = .026, for patient infections and 0.0340 vs. 0.166, P = .16, for infections per patient-year). Tissues from five patients, three with velour, were examined. Velour interfaces demonstrated more hyperkeratosis, hypergranulosis, and dermal inflammation. By ESEM, the silicone driveline tracts appeared relatively smooth and flat, whereas the velour interface samples were irregular with deep fissures and globular material adhering to the surface. Conclusions Using the silicone portion of the HMII driveline at the DLES was associated with fewer infections and a trend toward faster healing in this small retrospective series. Whether the intriguing microscopic differences directly account for this needs further study on a larger scale. [ABSTRACT FROM AUTHOR]

Background: The use of left ventricular assist devices (LVADs) as destination therapy (DT) is increasing and has proven beneficial in prolonging survival and improving quality of life in select patients with end-stage heart failure. Nonetheless, end-of-life (EOL) issues are inevitable and how to approach them underreported. Methods: Our DT data registry was queried for eligible patients, defined as those individuals who actively participated in EOL decision making. The process from early EOL discussion to palliation and death was reviewed. We recorded the causes leading to EOL discussion, time from EOL decision to withdrawal and from withdrawal to death, and location. Primary caregivers were surveyed to qualify their experience and identify themes relevant to this process. Results: Between 1999 and 2009, 92 DT LVADs were implanted in 69 patients. Twenty patients qualified for inclusion (mean length of support: 833 days). A decrease in quality of life from new/worsening comorbidities usually prompted EOL discussion. Eleven patients died at home, 8 in the hospital and 1 in a nursing home. Time from EOL decision to LVAD withdrawal ranged from <1 day to 2 weeks and from withdrawal until death was <20 minutes in all cases. Palliative care was provided to all patients. Ongoing assistance from the healthcare team facilitated closure and ensured comfort at EOL. Conclusions: With expanding indications and improved technology, more DT LVADs will be implanted and for longer durations, and more patients will face EOL issues. A multidisciplinary team approach with protocols involving DT patients and their families in EOL decision making allows for continuity of care and ensures dignity and comfort at EOL. [ABSTRACT FROM AUTHOR]

Objectives: This study investigates alterations in myocardial microvasculature, fibrosis, and hypertrophy before and after mechanical unloading of the failing human heart. Background: Recent studies demonstrated the pathophysiologic importance and significant mechanistic links among microvasculature, fibrosis, and hypertrophy during the cardiac remodeling process. The effect of left ventricular assist device (LVAD) unloading on cardiac endothelium and microvasculature is unknown, and its influence on fibrosis and hypertrophy regression to the point of atrophy is controversial. Methods: Hemodynamic data and left ventricular tissue were collected from patients with chronic heart failure at LVAD implant and explant (n = 15) and from normal donors (n = 8). New advances in digital microscopy provided a unique opportunity for comprehensive whole-field, endocardium-to-epicardium evaluation for microvascular density, fibrosis, cardiomyocyte size, and glycogen content. Ultrastructural assessment was done with electron microscopy. Results: Hemodynamic data revealed significant pressure unloading with LVAD. This was accompanied by a 33% increase in microvascular density (p = 0.001) and a 36% decrease in microvascular lumen area (p = 0.028). We also identified, in agreement with these findings, ultrastructural and immunohistochemical evidence of endothelial cell activation. In addition, LVAD unloading significantly increased interstitial and total collagen content without any associated structural, ultrastructural, or metabolic cardiomyocyte changes suggestive of hypertrophy regression to the point of atrophy and degeneration. Conclusions: The LVAD unloading resulted in increased microvascular density accompanied by increased fibrosis and no evidence of cardiomyocyte atrophy. These new insights into the effects of LVAD unloading on microvasculature and associated key remodeling features might guide future studies of unloading-induced reverse remodeling of the failing human heart. [Copyright &y& Elsevier]

Background: Thrombus formation on or near the aortic valve has been reported in HeartMate II (Thoratec, Pleasanton, CA) left ventricular assist device (LVAD) patients whose aortic valves do not open. With an akinetic valve, thrombogenesis is more likely. Thrombus formation may lead to neurologic events, placing the patient at greater risk. Aortic valve stenosis and/or regurgitation have also been observed with akinetic aortic valves. Assessing aortic valve opening is crucial when optimizing rotations per minute (rpm) to minimize embolic risk and aortic valve stenosis but presently relies solely on echocardiography, intermittent decreases in rpms to force aortic valve opening, and monitoring of pulse pressure. We hypothesized the electrical current waveforms of the HeartMate II would reveal whether the aortic valve was opening due to pressure changes in the left ventricle to allow for continuous monitoring and control of aortic valve opening ratios. Methods: Electrical HeartMate II current waveforms of patients from 2008 to 2009 that were recorded at the time of echocardiograph procedures were analyzed using a modified Karhunen-Loève transformation with a training set of electrical waveforms from 8,860 HeartMate II electrical current recordings from 2001 to 2009. Results: The study included 6 patients. The electrical current magnitude of the projection of the electrical current waveforms onto the training set''s eigenvectors was statistically significantly greater in 4 of the 6 patients when the aortic valve was closed, confirmed by echocardiography. The 2 patients who did not have a large increase in the magnitude had mild aortic valve regurgitation. Conclusion: Electrical current analysis for rotary non-pulsatile pumps is a means to develop a physiologic feedback algorithm for an auto-mode, which currently does not exist. Constant regulation and optimization of rotary non-pulsatile LVADs would minimize patients'' risk for neurologic events and aortic valve stenosis. [Copyright &y& Elsevier]

Left ventricular assist device (LVAD) implantation before heart transplantation has been associated with formation of antibodies directed against human leukocyte antigens (HLA), often referred to as sensitization. This study investigated whether prior sensitization or LVAD type affected the degree of post-implantation sensitization. The records of consecutive HeartMate (HM) I and HM II LVAD patients were reviewed. Panel reactive antibody (PRA) was assessed before LVAD implantation and biweekly thereafter. Sensitization was defined as PRA > 10%, and high-degree sensitization was defined as PRA > 90%. An HM LVAD was implanted in 64 patients, and 11 received a HM II LVAD as a bridge to transplant. Ten HM I patients (16%) were sensitized before LVAD implantation (HM I-S), and 54 (84%) were not (HM I-Non-S). Nine HM I-S patients (90%) became highly sensitized (PRA > 90%) compared with 9 HM I-Non-S patients (16.7%; p < 0.001). The PRA remained elevated (> 90%) in 8 of the 9 (88.9%) highly sensitized HM I-S patients vs 5 of the 9 (55.6%) HM I-Non-S highly sensitized patients. The PRA levels in the rest of the HM I-S highly sensitized patients declined from 93% ± 4% to 55% ± 15% (p = 0.01). Among the 11 HM II patients, 1 (9%) was sensitized before LVAD implantation (PRA, 40%) and the PRA moderately increased to 80%. No other HM II patient became sensitized after implantation. Thus, 1 of 11 (9%) HM II patients became sensitized compared with 29 of 64 (45%) HM I patients (p = 0.04). Pre-sensitized patients are at higher risk for becoming and remaining highly HLA-allosensitized after LVAD implantation. The HeartMate II LVAD appears to cause less sensitization than HeartMate I. [Copyright &y& Elsevier]

An increasing number of patients are living with ventricular assist devices (VADs). Many of these patients will require noncardiac surgery for conditions not directly related to their VADs. The aim of this study was to assess the risks and outcomes of noncardiac surgery in these patients. Perioperative and follow-up data from patients with VADs who underwent noncardiac surgery from 1993 to 2006 were analyzed. In that period, 184 VADs were implanted in 155 patients. Thirty-seven patients (24%) subsequently underwent 59 noncardiac surgeries. The mean duration of VAD support before surgery was 229 days. Bleeding was the most common postsurgical complication (10%), necessitating reexploration in 20% of abdominal surgeries. Thirty-day mortality was 12%. No deaths were caused by direct complications of surgery. Successful transplantation occurred in 72% of bridge to transplantation patients who required noncardiac surgery, compared with 71% of these patients who did not require noncardiac surgery (relative risk 1.0, p = 0.9). The average duration of VAD support after noncardiac surgery for destination therapy patients was 324 days, most of which time was spent at home. In conclusion, outcomes after noncardiac surgery in patients with VADs are favorable, and most patients continue to benefit from the intended purpose of mechanical circulatory support after recovering from noncardiac surgery. [Copyright &y& Elsevier]

Background: The current International Society for Heart and Lung Transplantation (ISHLT) diagnostic criteria for antibody-mediated rejection (AMR) designate AMR as either absent (AMR 0) or present (AMR 1), without grading its severity. Yet, the extent of histologic and immunofluorescence (IF) findings of AMR varies across endomyocardial biopsies (EMBs). In this study, we hypothesized that the severity of AMR, as assessed on EMBs, correlates with cardiovascular mortality in heart transplant recipients. Methods: All EMBs from 1985 to 2005 were evaluated. Biopsy specimens were uniformly studied by light microscopy and IF early post-transplant. A comprehensive vascular score (V1: no AMR, to V5: severe AMR) was prospectively assigned to each EMB, based on severity of both histologic and IF findings. Univariate Cox proportional hazards regressions were performed using indicators of vascular scores alone, combined, and cumulatively. Results: Nine hundred six patients were transplanted and included in the study. Mean age was 46.6 ± 15.5 years and 82% were male. A total of 26,236 EMBs comprised the study data. As expected, histologic and immunopathologic findings of AMR varied in severity. An incremental risk of cardiovascular mortality was found with more severe AMR whether vascular scores were analyzed individually (p = 0.001), in combination (p = 0.01) or cumulatively (p = 0.006). Conclusions: The severity of AMR on EMBs correlates with an incremental cardiovascular mortality risk after heart transplantation, suggesting that AMR should be viewed as a spectrum rather than just as present or absent. Supplementing the ISHLT AMR diagnostic guidelines with a consensus severity scale is warranted. [Copyright &y& Elsevier]