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Introduction: Implementation of continuous flow (CF) technology in modern ventricular assist devices (VAD) has afforded a wealth of engineering and design advantages in the development of a total artificial heart (TAH). However, clinical application of CF has created a unique physiologic state, the consequences of which remain largely unknown. We sought to evaluate clinical and biochemical markers of end-organ function in calves supported with biventricular CF VADs for more than 30 days. Methods: Eight calves survived longer than 30 days following biventriculectomy and implantation of dual CF VADs. Four types of CF pumps were utilized for the study. Serial hematologic and biochemical profiles were drawn as markers for end-organ function, and hemodynamic data—including pump flows and intravascular pressures—were continuously monitored. Results: The eight calves survived an average of 58.8 days (range 30–92 days). Two of the calves were electively terminated at the conclusion of the study period, while the remaining animals were euthanized as a result of respiratory distress ( n = 2) or impaired pump flows ( n = 4). In each case, serial biochemical and hematologic values were suggestive of preserved end-organ function. Six animals successfully participated in treadmill exercise evaluations. No evidence of end-organ damage was encountered upon necropsy or histologic tissue analysis. Conclusion: Biventricular CF VAD implantation permits a viable bovine CFTAH model capable of demonstrating long-term survival. After 30 days of completely nonpulsatile flow, cumulative hemodynamic, clinical, biochemical, and histological analyses were consistent with preserved end-organ function, suggesting previously unreported long-term feasibility of a CFTAH design.

Recent trends in cardiac surgery have encouraged total arterial coronary revascularization, citing advantages in long-term patency and overall mortality. Often relying on sequenced, composite, and free-graft strategies, total arterial coronary revascularization is limited by conduit availability and surgical complexity. We present the use of bilateral internal mammary artery grafts to achieve nonsequential 3-vessel total arterial coronary revascularization using the preserved distal bifurcation of the right internal mammary artery. Utilization of distal internal mammary artery branches should be considered a viable strategy in select patients and can broaden the opportunities for total arterial coronary revascularization in patients with multivessel coronary disease.

Continuous-flow left ventricular assist devices have proved to be effective, durable, life-saving tools in patients with end-stage heart failure. However, because of the risks associated with mechanical circulatory support (including stroke, infection, gastrointestinal bleeding, and device malfunction), the optimal goal of device therapy is myocardial recovery and device removal. Ventricular reconditioning and pump explantation after continuous-flow support have been reported; however, little is known about variables that govern the pace and degree of myocardial response in patients who experience such recovery. We describe our long-term pump-weaning strategy for a 25-year-old man who had a continuous-flow device implanted and then needed more than 5 years of support from it before developing cardiac reserve sufficient to enable pump explantation. To our knowledge, this is the longest period of uninterrupted continuous-flow device support to end in successful pump deactivation and a return to medical therapy. This case highlights the importance of actively and persistently pursuing a device-weaning strategy in all patients who need left ventricular assist device therapy.

Objectives Mitral regurgitation (MR) is common in patients with end-stage heart failure. We assessed the effect of performing concomitant mitral valve repair during continuous-flow left ventricular assist device (CF-LVAD) implantation in patients with severe preoperative MR. Methods We performed a single-centre, retrospective review of all patients who underwent CF-LVAD implantation between December 1999 and December 2013 (n = 469). Patients with severe preoperative MR (n = 78) were identified and then stratified according to whether they underwent concomitant valve repair. Univariate and survival analyses were performed, and multivariable regression was used to determine predictors of survival. Results Of the 78 patients with severe MR, 21 underwent valve repair at the time of CF-LVAD implantation (repair group) and 57 did not (non-repair group). A comparison of the 2 groups showed significant differences between groups: INTERMACS I 16.985 vs 9.52%, (P = 0.039), cardiopulmonary bypass time 82.09 vs 109.4 min (P = 0.0042) and the use of HeartMate II 63.16 vs 100% (P = 0.001). Survival analysis suggested trends towards improved survival and a lower incidence of heart failure-related readmissions in the repair group. Multivariable regression analysis showed no significant independent predictors of survival (mitral valve repair: odds ratio 0.4, 95% confidence interval 0.8-1.5; P = 0.2). Conclusions Despite the lack of statistical significance, trends towards improved survival and a lower incidence of heart failure events suggest that mitral valve repair may be beneficial in patients undergoing CF-LVAD implantation. Given the known relationship between severe MR and mortality, further study is encouraged to confirm the value of mitral valve repair in these patients.

The management of valvular heart disease has been dramatically influenced by recent evolutions in biomedical technology and surgical practice. With an aging population worldwide and accompanying increase in the prevalence of surgical valve disease, an understanding of prosthetic valve behavior and durability is essential for proper patient selection and management. This report offers an overview of the definitions, mechanisms, management, and clinical impact of structural valve degeneration and failure. Published literature has employed variable definitions and outcome measures, complicating our understanding of bioprosthetic valve behavior and function. The pathophysiology leading to structural valve degeneration is multifactorial and involves mechanical, hematologic, and immunologic elements. Technological advancements have resulted in improved valve performance and new strategies to mitigate the risks of degeneration. While mechanical valves have demonstrated negligible durability concerns, the benefits of bioprosthetic valves must be weighed against their potential for structural degeneration and subsequent reintervention. Valve selection should involve patient-specific deliberation, and guidelines have been established to help guide risk reduction strategies. Surgical valve replacement remains the standard of care for prosthetic valve failure, but emerging technology offers the potential to slow the development of structural degeneration and transcatheter valve-in-valve options are being increasingly explored.

Although biventricular heart failure has been successfully managed with dual continuous-flow ventricular assist devices, the long-term use of 2 mechanically dissimilar pumps has traditionally been discouraged. We present the case of a 52-year-old man whose treatment with a HeartMate II left ventricular assist device was complicated by right ventricular failure, necessitating the implantation of a long-term right ventricular assist device. A HeartWare left ventricular assist device was placed along the right ventricular base to avoid interference with the HeartMate II housing. The patient was discharged from the hospital after routine postoperative care and dual-device training. This case shows that, despite logistical complexities, nonidentical continuous-flow device pairings can successfully provide long-term biventricular support.

We describe the successful use of long-term biventricular continuous-flow mechanical circulatory support as a bridge to transplantation in a small-framed 63-year-old woman with long-standing nonischemic cardiomyopathy. After placement of a left-sided HeartWare HVAD, persistent right-sided heart failure necessitated implantation of a second HeartWare device for long-term right ventricular support. After 262 days, the patient underwent successful orthotopic heart transplantation and was discharged from the hospital. This report indicates the feasibility of biventricular device support in older patients of relatively small stature, and our results may encourage others to consider this therapy in similar patient populations.

The widespread use of continuous-flow left ventricular assist devices for mechanical circulatory support has shown that long-term hemodynamic support is possible, even when a clinical “pulse” cannot be detected. We present the incidental discovery of ventricular fibrillation in 6 alert, hemodynamically stable patients supported only by a continuous-flow device (HeartMate II, n=5; Jarvik 2000, n=1). Ventricular fibrillation was found in 3 patients during routine outpatient follow-up visits and in 3 awaiting discharge from the hospital after device placement. Diagnosis was confirmed by electrocardiographic and echocardiographic studies. The average duration of mechanical circulatory support before ventricular fibrillation occurred was 221 ± 362 days (range, 5–864 d). All patients were conscious and ambulatory at the time of the arrhythmia. Three patients reported symptoms—primarily fatigue, nausea, and exertional dyspnea—that prompted evaluation. Serum chemistry analysis of blood drawn immediately after diagnosis showed no changes that suggested end-organ dysfunction. Three patients died of unrelated complications an average of 3.9 yr (range, 360–2,270 d) after the event. Two of the remaining 3 patients eventually underwent successful pump explantation, and one is on ongoing support. Our experience shows that it is possible for patients with continuous-flow left ventricular assist devices to remain hemodynamically stable while in ventricular fibrillation. Additional investigation is needed to determine whether defibrillator settings for these patients should be adjusted to limit delivery of shock therapy.

In the setting of increasingly complex medical therapies and limited physician resources, the recent emergence of ‘smart’ technology offers tremendous potential for improved logistics, efficiency, and communication between medical team members. In an effort to harness these capabilities, we sought to evaluate the utility of this technology in surgical practice through the employment of a wearable camera device during cardiothoracic organ recovery. A single procurement surgeon was trained for use of an Explorer Edition Google Glass™ (Google Inc., Mountain View, CA) during the recovery process. Live video feed of each procedure was securely broadcast to allow for members of the home transplant team to remotely participate in organ assessment. Primary outcomes involved demonstration of technological feasibility and validation of quality assurance through group assessment. The device was employed for the recovery of four organs: a right single lung, a left single lung, and two bilateral lung harvests. Live video of the visualization process was remotely accessed by the home transplant team, and supplemented final verification of organ quality. In each case, the organs were accepted for transplant without disruption of standard procurement protocols. Media files generated during the procedures were stored in a secure drive for future documentation, evaluation, and education purposes without preservation of patient identifiers. Live video streaming can improve quality assurance measures by allowing off-site members of the transplant team to participate in the final assessment of donor organ quality. While further studies are needed, this project suggests that the application of mobile ‘smart’ technology offers not just immediate value, but the potential to transform our approach to the practice of medicine.

While the modern armamentarium for the treatment of ischemic heart disease includes ever-improving pharmaceutical therapies, percutaneous interventions, and coronary artery bypass grafting, standard modalities are not always sufficient in the treatment of advanced disease. Indeed, the number of patients with symptomatic chronic disease continues to rise in the United States – likely due to advancements in medical therapy. As a result of this challenge, researchers have long sought to develop alternative strategies to more traditional revascularization techniques. In the 1990s transmyocardial laser revascularization (TMLR) emerged as an effective treatment modality for patients with severe coronary disease not amenable to conventional therapy. Although the specific mechanisms leading to reperfusion and symptom relief remain controversial, studies have shown laser therapy to significantly improve angina in select patient groups, rendering it an important therapeutic option in the treatment of severe coronary artery disease.

s S237 Pittsburgh, PA; 2Departments of Psychiatry, Epidemiology, & Biostatistic, University of Pittsburgh Medical Center, Pittsburgh, PA. Purpose: Right ventricular failure (RVF) after left ventricular assist device (LVAD) placement is often perilous. It has been hypothesized that in patients with advanced heart failure, RVF is linked to weight loss and measures of abnormal body composition, such as low body mass index (BMI). This postulate is examined in a cohort of LVAD supported patients. Methods: A retrospective analysis was performed of 114 continuous flow LVAD supported patients from 2004-2011. RVF was defined as need for right ventricular mechanical support or > 14 days of inotropic support postimplant. Three patient groups were identified based on the sample’s BMI distribution: lowest group (lowest quintile, BMI 33, n= 23). Kaplan-Meier analysis was used to compare the freedom from RVF; multivariate Coxregression analysis was performed to determine risk factors for RVF. Results: The BMI groups (lowest, intermediate, highest) were similar with regards to all pre-operative characteristics except age (56y, 59y, 47y, p= 0.002), non-ischemic/idiopathic diagnosis (22%, 1%, 9%, p= 0.004), emergent LVAD implantation (0%, 4%, 17%, p= 0.032), and pre-implant heart rate ( 104, 85, 95, p= 0.001). Figure 1 shows that freedom from RVF was significantly worse for the lowest BMI group compared to the intermediate BMI group (p= 0.019) and the intermediate and highest BMI groups combined (p= 0.021). There was no difference between the intermediate and highest BMI groups (p= 0.500) or the lowest and highest BMI groups (p= 0.185). Coxregression analysis revealed lowest BMI group (HR 2.519, p= 0.016, CI 1.187-5.347) and emergent device placement (HR 3.392, p= 0.028, CI 1.141-10.09) were independent risk factors for RVF. Conclusion: In LVAD patients, a low BMI is associated with heightened risk for RVF after device placement. Investigation of other potential markers of abnormal body composition may broaden our understanding of post-LVAD RVF.

Purpose: Donation after cardiac death (DCD) to overcome the donor organ shortage is well accepted in the clinical setting, although the longterm outcome after DCD lung transplantation (LTx) remains largely unknown. Methods: In this retrospective study, DCD LTx recipients (n= 59) were compared with a cohort of donation-after-brain-death (DBD) LTx recipients (n= 331) transplanted between February 2007 and September 2013. Survival and incidence of chronic lung allograft dysfunction (CLAD), were assessed and compared over a median follow-up of 33.4 (±2.8) months for DCD and 40.7 (±2.8) months for DBD(p= 0.049). Results: There were no differences between groups with regard to patient characteristics: age (p= 0.78), underlying disease (p= 0.30) and type of type of LTx (p= 0.10); Except for gender more male predominance was seen in the DCD group (37 of 59(62%) vs 160 of 331(48%)) (p= 0.048). Nine patients (15%) in the DCD group developed CLAD vs 65 patients (20%) in the DBD group (p= 0.48). Freedom from CLAD did not differ between the groups (p= 0.90, figure). In the DCD group, 14 of 59 patients (24%) died, vs 62 of 331 patients (19%) in the DBD group (p= 0.38). Actuarial survival rates 1 year, 3 years and 5 years are 88%, 75% and 71% for the DCD group and 91%, 84% and 80% for the DBD group (p= 0.13, figure). Conclusion: In our experience, long-term outcome in DCD lung recipients is comparable to that of DBD lung recipients. ( 671)

Single gene mutations in beta integrins can account for functional defects of individual cells of the hematopoietic system. In humans, mutations in beta(2) integrin lead to leukocyte adhesion deficiency (LAD) syndrome and mutations in beta(3) integrin cause the bleeding disorder Glanzmann thrombasthenia. However, multiple defects in blood cells involving various beta integrins (beta(1), beta(2), and beta(3)) occur simultaneously in patients with the recently described LAD type III (LAD-III). Here we show that the product of a single gene, Ca(2+) and diacylglycerol-regulated guanine nucleotide exchange factor I (CalDAG-GEFI), controlled the activation of all 3 integrins in the hematopoietic system. Neutrophils from CalDAG-GEFI(-/-) mice exhibited strong defects in Rap1 and beta(1) and beta(2) integrin activation while maintaining normal calcium flux, degranulation, and ROS generation. Neutrophils from CalDAG-GEFI-deficient mice failed to adhere firmly to stimulated venules and to migrate into sites of inflammation. Furthermore, CalDAG-GEFI regulated the activation of beta(1) and beta(3) integrins in platelets, and CalDAG-GEFI deficiency caused complete inhibition of arterial thrombus formation in mice. Thus, mice engineered to lack CalDAG-GEFI have a combination of defects in leukocyte and platelet functions similar to that of LAD-III patients.

difference in mortality (Figure 1) or other clinical outcomes (Table 1). Age > 65 was not a risk factor for mortality (HR 1.2, 95% CI 0.6-2.6, p= 0.5) however redo surgery was (HR 1.7, 95% CI 1.1-2.9, p= 0.04). Sensitivity analyses at age thresholds found significant divergence in survival curves at 70 years, however age did not emerge as an independent predictor of mortality and the cohort sample was not sufficient for meaningful conclusions. Conclusion: This is a large cohort of contemporary patients with CF LVADs with the longest follow-up in the literature. CF LVADs are an effective safe option in elderly; age is less likely an issue versus poor protoplasm or complex operations such as redo cardiac operation.