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The Levitronix CentriMag is a magnetically levitated centrifugal-flow pump that can be implanted rapidly in the operating room for both right and left ventricular support. Recently, continuous-flow pumps have been associated with excessive bleeding, which can be at least partially explained by acquired von Willebrand disease (vWD). We investigated whether acquired vWD occurs during CentriMag support and determined the frequency of bleeding complications during device support as well as after transition to long-term support. We found that acquired vWD is common early post CentriMag implantation and is associated with frequent bleeding events and high requirement of blood products.

Background: Aortic insufficiency (AI) is increasingly recognized as a complication of continuous flow left ventricular assist device support; however, its long-term prevalence, clinical significance, and efficacy of potential interventions are not well known., Methods and Results: We studied the prevalence and management of AI in 232 patients with continuous flow left ventricular assist device at our institution. Patients with aortic valve (AV) surgery before left ventricular assist device implantation were excluded from analysis. To examine the prevalence of de novo AI, patients without preoperative AI were divided into a retrospective and a prospective cohort based on whether a dedicated speed optimization study had been performed at the time of discharge. Forty-three patients underwent AV repair at the time of implant, and 3 subsequently developed greater than mild AI. In patients without surgical AV manipulation and no AI at the time of implant, Kaplan-Meier analysis revealed that freedom from greater than mild de novo AI at 1 year was 77.6±4.2%, and that at least moderate AI is expected to develop in 37.6±13.3% after 3 years. Nonopening of the AV was strongly associated with de novo AI development in patients without prospective discharge speed optimization. Seven of 21 patients with at least moderate AI developed symptomatic heart failure requiring surgical intervention., Conclusions: AI is common in patients with continuous flow left ventricular assist devices and may lead to clinical decompensation requiring surgical correction. The prevalence of AI is substantially less in patients whose AV opens, and optimized loading conditions may reduce AI prevalence in those patients in whom AV opening cannot be achieved.

Background: Continuous-flow left ventricular assist devices (CF-LVADs) are increasingly used to support patients with advanced heart failure (HF). Device thrombosis is a serious complication of CF-LVADs, but its precise prevalence and etiology remains uncertain., Methods: Root-cause analysis was performed in all cases with device thrombosis confirmed upon explant among patients implanted with a HeartMate II (HM II) from January 1, 2009 to November 15, 2012. Cannula position and bend relief integrity were assessed and charts were reviewed with particular attention to anti-coagulation and infection profiles., Results: Nineteen of 177 patients (11%) were found to have device thrombosis of various etiologies after a mean of 351 ± 311 days, representing 0.12 event/patient-year. Of the 5 mechanically induced thromboses, proximate etiology was severely abnormal inflow cannula position in 3 patients and bend relief disconnect with deformed outflow graft in 2 patients. One patient had a hypercoagulable disorder with prior arterial embolism. In the remaining 13 patients (age 61 ± 14 years, 77% male, 69% Caucasian), "non-mechanical" device thrombosis occurred after 357 ± 383 days; INR at the time of diagnosis was 1.81 (1.62 to 2.07); and mean device speed was 8,855 ± 359 rpm. Five of 13 patients (38%) had an infection during the month leading up to device thrombosis. Of note, lactate dehydrogenase (LDH) was already elevated at the time of discharge in patients who would later develop non-mechanical device thrombosis (423 [354 to 766] vs 352 [272 to 373] U/liter, p < 0.01)., Conclusions: Device thrombosis is a multifactorial phenomenon, and differentiation of mechanical and non-mechanical causes is an essential step for individual diagnosis and treatment plans. Larger studies excluding patients with obvious mechanical etiology are needed to investigate biologic and/or management-related risk factors for device thrombosis. Our findings suggest that LDH may be an early risk marker. Due to the difficulty in treating late-stage device thrombosis, we suggest early use of simple tests to rule out both causes of thrombosis, such as X-rays and closer LDH monitoring (bi-weekly)., (© 2014 International Society for Heart and Lung Transplantation Published by International Society for the Heart and Lung Transplantation All rights reserved.)

Objectives: This study sought to develop a novel approach to optimizing continuous-flow left ventricular assist device (CF-LVAD) function and diagnosing device malfunctions., Background: In CF-LVAD patients, the dynamic interaction of device speed, left and right ventricular decompression, and valve function can be assessed during an echocardiography-monitored speed ramp test., Methods: We devised a unique ramp test protocol to be routinely used at the time of discharge for speed optimization and/or if device malfunction was suspected. The patient's left ventricular end-diastolic dimension, frequency of aortic valve opening, valvular insufficiency, blood pressure, and CF-LVAD parameters were recorded in increments of 400 rpm from 8,000 rpm to 12,000 rpm. The results of the speed designations were plotted, and linear function slopes for left ventricular end-diastolic dimension, pulsatility index, and power were calculated., Results: Fifty-two ramp tests for 39 patients were prospectively collected and analyzed. Twenty-eight ramp tests were performed for speed optimization, and speed was changed in 17 (61%) with a mean absolute value adjustment of 424 ± 211 rpm. Seventeen patients had ramp tests performed for suspected device thrombosis, and 10 tests were suspicious for device thrombosis; these patients were then treated with intensified anticoagulation and/or device exchange/emergent transplantation. Device thrombosis was confirmed in 8 of 10 cases at the time of emergent device exchange or transplantation. All patients with device thrombosis, but none of the remaining patients had a left ventricular end-diastolic dimension slope >-0.16., Conclusions: Ramp tests facilitate optimal speed changes and device malfunction detection and may be used to monitor the effects of therapeutic interventions and need for surgical intervention in CF-LVAD patients., (Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aims: Giant cell myocarditis (GCM) carries a poor prognosis and many patients require end-stage therapies. This study sought to determine the outcome of patients bridged with ventricular assist devices (VAD) to orthotopic heart transplantation (OHT)., Methods and Results: A retrospective data collection of all patients with GCM was performed. Diagnosis was determined by endomyocardial or explanted heart biopsy. Eight patients were found, but two of those patients went directly to OHT and were excluded. The remaining six patients received VADs, and these patients, aged 44 ± 18 years, were included. Five of the six patients were bridged with biventricular support and one patient was supported by left ventricular assist device (LVAD) alone. Two patients died on device support. Four patients were bridged to OHT 77 ± 42 days after device implantation. All four patients bridged with a VAD are alive, with a mean follow-up of 5.7 ± 4.1 years. Two patients were found to have recurrent GCM in the transplanted heart and were treated successfully with immunosuppression. Three patients had high grade (2R) rejection at 66 ± 52 days post-OHT. Cardiac function was preserved in all patients, and only one patient had cardiac allograft vasculopathy., Conclusion: Patients with end-stage GCM can be successfully bridged with VADs to OHT with very good post-OHT survival. The proper immunosuppressive regimen for this group needs further investigation given the frequency of rejection and GCM recurrence.