Single-Center Experience With Protocolized Treatment of Left Ventricular Assist Device Infections.

Purpose: Because of the current lack of evidence-based antimicrobial treatment guidelines, Left Ventricular Assist Device (LVAD) infections are often treated according to local insights. Here, we propose a flowchart for protocolized treatment, in order to improve outcome. Methods: The flowchart was composed based on literature, consensus and expert opinion statements. It includes choice, dosage and duration of antibiotics, and indications for suppressive therapy, with particular focus on Staphylococcus aureus (SA) (Figure 1). The preliminary treatment results of 28 patients (2 from start cephalexin suppressive therapy) after implementation in July 2018 are described. Results: Cumulative incidence for first episode of infection in a 3-year time period was 27% (26 of 96 patients with an LVAD). Twenty-one of 23 (91%) first episodes of driveline infection (10 superficial and 13 deep; nine of 13 caused by SA) were successfully treated with antibiotics according to flowchart with complete resolution of clinical signs and symptoms. For two patients with deep driveline infections, surgery was needed in addition. There were no relapses of deep driveline infections, and only 2 SA deep driveline re-infections after 6 months. Nine patients received cephalexin of whom four patients (44%) developed a breakthrough infection with cephalexin-resistant gram-negative bacteria. Conclusions: The first results of this protocolized treatment approach of LVAD infections are promising. Yet, initiation of cephalexin suppressive therapy should be carefully considered given the occurrence of infections with resistant micro-organisms. The long-term outcome of this approach needs to be established in a larger number of patients, preferably in a multi-center setting.

Rate of thromboembolic and bleeding events in patients undergoing concomitant aortic valve surgery with left ventricular assist device implantation.

BACKGROUND: Significant aortic regurgitation at the time of left ventricular assist device (LVAD) implantation, requires concomitant aortic valve (AoV) replacement or repair. However, the impact of concomitant AoV surgery on morbidity remains unknown. Therefore, our aim is to determine the impact of concomitant AoV surgery on thromboembolic and bleeding events. METHODS: A retrospective IMACS registry study, including patients implanted from 2013 until September 2017. Differences between different concomitant AoV surgery modalities were analyzed. RESULTS: In total, 785 (5.1%) out of 15.267 patients (median age 58 IQR 49-66 years, 79% male) underwent concomitant AoV surgery (median age 63 IQR 54-69 years, 84% male); 386 (49%) patients received biological prostheses, 71 (9%) mechanical prostheses and 328 (42%) AoV repairs. In total, 54 (8%) patients with AoV surgery experienced a thromboembolic event and 1016 (9%) patients with no AoV surgery. Furthermore, concomitant AoV surgery was associated with an increased rate of all and nonsurgical bleedings. Following a multivariable Cox regression, concomitant AoV surgery remained an independent predictor for bleeding events. CONCLUSIONS: In LVAD patients undergoing concomitant AoV surgery, thromboembolic event rates were not higher, however both all and nonsurgical bleeding event rates were higher.

Survival and adverse events in patients with atrial fibrillation at left ventricular assist device implantation: an analysis of the European Registry for Patients with Mechanical Circulatory Support.

OBJECTIVES: Atrial fibrillation (AF) is a risk factor for mortality and cerebrovascular accidents (CVAs) and is common in patients with heart failure. This study evaluated survival and adverse events in patients with a left ventricular assist device (LVAD) and a history of AF in the European Registry for Patients with Mechanical Circulatory Support. METHODS: Patients with a continuous-flow LVAD, AF or sinus rhythm (SR) and a follow-up were included. Kaplan-Meier analyses for survival (including a propensity-scored matched analysis), freedom from CVA, pump thrombosis, bleeding and a composite of pump thrombosis/CVA were performed. To correct for covariate imbalance, a Kaplan-Meier (KM) analysis was performed after propensity score (PS) matching the groups. Finally, a Cox regression was performed for predictors of lower survival. RESULTS: Overall, 1821 patients (83% male) were included, with a median age of 57 years and a median follow-up of 13.1 months (interquartile range: 4.3-27.7). Preoperative Electrocardiogram (ECG) rhythm was AF in 421 (23.1%) and SR in 1400 (76.9%) patients. Patients with pre-LVAD AF had a lower ≤90-day (81.9% vs 87.1%, P = 0.0047) and 4-year (35.4% vs 44.2%, P = 0.0083) survival compared to SR. KM analysis with PS matching groups revealed a trend (P = 0.087) towards decreased survival. Univariable analyses confirmed pre-LVAD AF as a predictor for mortality, but the multivariable analysis did not. No difference in the rate of adverse events was found. An analysis of patients at 24 months revealed a higher rate of CVAs for pre-LVAD AF patients (77% vs 94.3%, P < 0.0001). CONCLUSIONS: Patients with pre-LVAD AF undergoing LVAD implantation had a worse survival. However, after performing a multivariate analysis, and PS matching analysis, AF was no longer significant, indicating a worser preoperative condition in these patients. Concerning thrombo-embolic events, only patients with pre-LVAD AF alive beyond 24 months have a higher risk of CVAs.

Right ventricular functional assessment by 2D multi-plane echocardiography prior to left ventricular assist device implantation.

OBJECTIVES: Right ventricular (RV) failure post left ventricular assist device (LVAD) implantation is associated with increased morbidity and mortality. A novel RV multi-plane imaging method using two-dimensional echocardiography and electronic plane rotation (MPE) was used to quantify RV function prior to LVAD implantation and to identify potential added value in this patient population. METHODS: In twenty-five end-stage heart failure patients (age 58.9 ± 6.8 years, 76% male), systolic function of four different RV walls (lateral, anterior, inferior and inferior coronal) were evaluated from one focussed apical view using MPE. RESULTS: Feasibility of tricuspid annular plane systolic excursion (TAPSE) and tricuspid annular peak systolic velocity (RV-S') measurements were high (84-100%), with lower TAPSE values measured in the inferior (14.2 ± 4.6 mm) and inferior coronal (12.3 ± 5.0 mm) walls compared to the lateral (16.3 ± 4.5 mm) and anterior walls (16.0 ± 4.5 mm). RV wall longitudinal strain (RV-LS) measurement was most feasible in the lateral wall (80%; mean: -12.1 ± 4.2%). TAPSE and RV-LS values were significantly reduced in patients compared to matched healthy individuals (p = <0.001). Seven (28%) patients who developed moderate to severe RV failure (RVF) early post-implant (≤30 days) had lower pre-implant values across all multi-plane parameters compared to those without significant post-implant RVF, notably four-wall averaged TAPSE (11.1 ± 3.4 mm vs 15.9 ± 4.0 mm; p = 0.02). CONCLUSION: 2D MPE was highly feasible for RV wall quantification pre-LVAD surgery, detecting differences in regional wall function. This novel method comprehensively quantifies RV wall function and could complement current pre-LVAD screening protocols.

Driveline exit-site care protocols in patients with left ventricular assist devices: a systematic review.

OBJECTIVES: Driveline infections continue to be a significant complication following left ventricular assist device (LVAD) implantation. Driveline exit-site care is crucial for the prevention of infections; however, there are no uniform guidelines. The goal of this study was to provide an overview of the currently published driveline exit-site care protocols in patients with LVAD. METHODS: A systematic literature review was performed. Studies before 15 December 2020 were included if the number of driveline infections was a primary outcome and the driveline exit-site care protocol was explained. RESULTS: Eleven articles were included in the systematic review, including 1602 patients with LVADs. The median of the frequency of driveline infections in the articles was 13.8% with a range of 0-52.6%. There was a marked variability in the methods of care of driveline exit sites, without a standardized driveline dressing technique in patients with LVADs. The frequency of driveline infections was 6-7.5% in studies using a dressing kit that included chlorhexidine, a silver-based dressing and an anchoring device. Furthermore, there was variability in the anchoring devices and the frequency of dressing changes, which varied from daily to weekly. No specific anchoring device or change frequency was found to be superior. CONCLUSIONS: Based on this systematic review, driveline exit care protocols that included chlorhexidine, a silver-based dressing, the use of an anchoring device and dressing kits might be best in reducing driveline infection rates. However, prospective studies with larger cohorts are needed to establish the optimal protocol for driveline exit-site care.

Evaluation of patients with a HeartMate 3 left ventricular assist device using echocardiographic particle image velocimetry.

PURPOSE: Poor left ventricular (LV) function may affect the physiological intraventricular blood flow and physiological vortex formation. The aim of this study was to investigate the pattern of intraventricular blood flow dynamics in patients with LV assist devices (LVADs) using echocardiographic particle image velocimetry. MATERIALS AND METHODS: This prospective study included 17 patients (mean age 57 ± 11 years, 82% male) who had received an LVAD (HeartMate 3, Abbott Laboratories, Chicago, Illinois, USA) because of end-stage heart failure and poor LV function. Eleven (64%) patients had ischemic cardiomyopathy, and six patients (36%) had nonischemic cardiomyopathy. All patients underwent echocardiography, including intravenous administration of an ultrasound-enhancing agent (SonoVue, Bracco, Milan, Italy). Echocardiographic particle image velocimetry was used to quantify LV blood flow dynamics, including vortex formation (Hyperflow software, Tomtec imaging systems Gmbh, Unterschleissheim, Germany). RESULTS: Contrast-enhanced ultrasound was well tolerated in all patients and was performed without adverse reactions or side effects. The LVAD function parameters did not change during or after the ultrasound examination. The LVAD flow was on average 4.3 ± 0.3 L/min, and the speed was 5247 ± 109 rotations/min. The quantification of LV intraventricular flow demonstrated substantial impairment of vortex parameters. The energy dissipation, vorticity, and kinetic energy fluctuation indices were severely impaired. CONCLUSIONS: Echo particle velocimetry is safe and feasible for the quantitative assessment of intraventricular flow in patients with an LVAD. The intraventricular LV flow and vortex parameters are severely impaired in these patients.

Survival following a concomitant aortic valve procedure during left ventricular assist device surgery: an ISHLT Mechanically Assisted Circulatory Support (IMACS) Registry analysis.

AIMS: The aim of this study was to compare early- and late-term survival and causes of death between patients with and without a concomitant aortic valve (AoV) procedure during continuous-flow left ventricular assist device (LVAD) surgery. METHODS AND RESULTS: All adult primary continuous-flow LVAD patients on the International Society of Heart and Lung Transplantation (ISHLT) Mechanically Assisted Circulatory Support (IMACS) Registry (n = 15 267) were included in this analysis and stratified into patients submitted to a concomitant AoV procedure (AoV replacement or AoV repair) and patients without an AoV procedure. The primary outcome was early (≤90 days) survival post-LVAD surgery. Secondary outcomes were late survival (survival during the entire follow-up period) and conditional survival (in patients who survived the first 90 days post-LVAD surgery), and determinants. Patients who underwent concomitant AoV replacement (n = 457) had significantly reduced late survival compared with patients with AoV repair (n = 328) or without an AoV procedure (n = 14 482) (56% vs. 61% and 62%, respectively; P = 0.001). After adjustment for other significant predictors, concomitant AoV replacement remained an independent predictor for early [hazard ratio (HR) 1.226, 95% confidence interval (CI) 1.037-1.449] and late (HR 1.477, 95% CI 1.154-1.890) mortality. However, patients undergoing AoV replacement or repair, in whom the presence of moderate-to-severe AoV regurgitation was diagnosed prior to LVAD implantation, had survival similar to patients not undergoing AoV interventions. CONCLUSIONS: Concomitant AoV surgery in patients undergoing LVAD implantation is an independent predictor of mortality. Additional research is needed to determine the best AoV surgical strategy at the time of LVAD surgery.

Aortic root thrombus after left ventricular assist device implantation and aortic valve replacement.

Data on the risk of aortic root thrombosis in patients with aortic valve replacement (AVR) and left ventricular assist device (LVAD) surgery are scarce. Two out of nine patients receiving AVR concomitant with LVAD surgery and two out of two patients receiving AVR on LVAD support, at our centre, developed an aortic root thrombus, all diagnosed with computed tomography (CT) angiography. These results demonstrate that patients with concomitant AVR and LVAD surgery, or AVR on LVAD support, have an increased risk of aortic root thrombosis. Therefore, early anti-thrombotic therapy and vigilant diagnostic follow-up, using CT scans, are warranted to prevent thromboembolic events.

Outcomes of patients after successful left ventricular assist device explantation: a EUROMACS study.

AIMS: Sufficient myocardial recovery with the subsequent explantation of a left ventricular assist device (LVAD) occurs in approximately 1-2% of the cases. However, follow-up data about this condition are scarcely available in the literature. This study aimed to report the long-term outcomes and clinical management following LVAD explantation. METHODS AND RESULTS: An analysis of the European Registry for Patients with Mechanical Circulatory Support was performed to identify all adult patients with myocardial recovery and successful explantation. Pre-implant characteristics were retrieved and compared with the non-recovery patients. The follow-up data after explantation were collected via a questionnaire. A Kaplan-Meier analysis for freedom of the composite endpoint of death, heart transplantation, LVAD reimplantion, or heart failure (HF) relapse was conducted. A total of 45 (1.4%) cases with myocardial recovery resulting in successful LVAD explantation were identified. Compared with those who did not experience myocardial recovery, the explanted patients were younger (44 vs. 56 years, P < 0.001), had a shorter duration of cardiac disease (P < 0.001), and were less likely to have ischaemic cardiomyopathy (9% vs. 41.8%, P < 0.001). Follow-up after explantation could be acquired in 28 (62%) cases. The median age at LVAD implantation was 43 years (inter-quartile range: 29-52), and 23 (82%) were male. Baseline left ventricular ejection fraction was 18% (inter-quartile range: 10-20%), and 60.7% of the patients had Interagency Registry for Mechanically Assisted Circulatory Support Profile 1 or 2. Aetiologies of HF were dilated cardiomyopathy in 36%, myocarditis in 32%, and ischaemic in 14% of the patients, and 18% had miscellaneous aetiologies. The devices implanted were HeartMate II in 14 (50%), HVAD in 11 (39%), HeartMate 3 in 2 (7%), and 1 unknown with a median duration of support of 410 days (range: 59-1286). The median follow-up after explantation was 26 months (range 0.3-73 months), and 82% of the patients were in New York Heart Association Class I or II. Beta-blockers were prescribed to 85%, angiotensin-converting enzyme inhibitors to 71%, and loop diuretics to 50% of the patients, respectively. Freedom from the composite endpoint was 100% after 30 days and 88% after 2 years. CONCLUSIONS: The survival after LVAD explantation is excellent without the need for heart transplantation or LVAD reimplantation. Only a minority of the patients suffer from a relapse of significant HF.

Emerging electromagnetic interferences between implantable cardioverter-defibrillators and left ventricular assist devices.

AIMS: To investigate the prevalence of electromagnetic interference (EMI) between left ventricular assist devices (LVADs) and implantable cardioverter-defibrillators (ICDs)/pacemakers (PMs). METHODS AND RESULTS: A retrospective single-centre study was conducted, including all patients undergoing HeartMate II (HMII) and HeartMate 3 (HM3) LVAD implantation (n = 106). Electromagnetic interference was determined by the inability to interrogate the ICD/PM. Overall, 85 (mean age 59 ± 8, 79% male) patients had an ICD/PM at the time of LVAD implantation; 46 patients with HMII and 40 patients with HM3. Among the 85 LVAD patients with an ICD's/PM's, 11 patients (13%) experienced EMI; 6 patients (15%) with an HMII and 5 patients (11%) with an HM3 (P = 0.59). Electromagnetic interference from the HMII LVADs was only present in patients with a St Jude/Abbott device; 6 of the 23 St Jude/Abbott devices. However, in the HM3 patients, EMI was mainly present in patients with Biotronik devices: 4 of the 18 with only one (1/25) patient with a Medtronic device. While initial interrogation of these devices was not successful, none of the 11 cases experienced pacing inhibition or inappropriate shocks. CONCLUSION: In summary, the prevalence of EMI between ICDs in the older and newer type of LVAD's remains rather high. While HMII patients experienced EMI with a St Jude/Abbott device (which was already known), HM3 LVAD patients experience EMI mainly with Biotronik devices. Prospective follow-up, preferably in large registries, is warranted to investigate the overall prevalence and impact of EMI in LVAD patients.

Impact of Continuous Flow Left Ventricular Assist Device Therapy on Chronic Kidney Disease: A Longitudinal Multicenter Study.

BACKGROUND: Many patients undergoing durable left ventricular assist device (LVAD) implantation suffer from chronic kidney disease (CKD). Therefore, we investigated the effect of LVAD support on CKD. METHODS: A retrospective multicenter cohort study, including all patients undergoing LVAD (HeartMate II (n = 330), HeartMate 3 (n = 22) and HeartWare (n = 48) implantation. In total, 227 (56.8%) patients were implanted as bridge-to-transplantation; 154 (38.5%) as destination therapy; and 19 (4.7%) as bridge-to-decision. Serum creatinine measurements were collected over a 2-year follow-up period. Patients were stratified based on CKD stage. RESULTS: Overall, 400 patients (mean age 53 ± 14 years, 75% male) were included: 186 (46.5%) patients had CKD stage 1 or 2; 93 (23.3%) had CKD stage 3a; 82 (20.5%) had CKD stage 3b; and 39 (9.8%) had CKD stage 4 or 5 prior to LVAD implantation. During a median follow-up of 179 days (IQR 28-627), 32,629 creatinine measurements were available. Improvement of kidney function was noticed in every preoperative CKD-stage group. Following this improvement, estimated glomerular filtration rates regressed to baseline values for all CKD stages. Patients showing early renal function improvement were younger and in worse preoperative condition. Moreover, survival rates were higher in patients showing early improvement (69% vs 56%, log-rank P = 0 .013). CONCLUSIONS: Renal function following LVAD implantation is characterized by improvement, steady state and subsequent deterioration. Patients who showed early renal function improvement were in worse preoperative condition, however, and had higher survival rates at 2 years of follow-up.

Impact of preoperative liver dysfunction on outcomes in patients with left ventricular assist devices.

OBJECTIVES: We evaluated the impact of preoperative liver function on early and 1-year postoperative outcomes in patients supported with a left ventricular assist device (LVAD) and subsequent evolution of liver function markers. METHODS: A retrospective multicentre cohort study was conducted, including all patients undergoing continuous-flow LVAD implantation. The Model for End-stage Liver Disease (MELD) score was used to define liver dysfunction. RESULTS: Overall, 290 patients with an LVAD [78% HeartMate II, 15% HVAD and 7% HeartMate 3, mean age 55 (18), 76% men] were included. Over 40 000 measurements of liver function markers were collected over a 1-year period. A receiver operating characteristic curve analysis for the 1-year mortality rate identified the optimal cut-off value of 12.6 for the MELD score. Therefore, the cohort was dichotomized into patients with an MELD score of less than or greater than 12.6. The early (90-day) survival rates in patients with and without liver dysfunction were 76% and 91% (P = 0.002) and 65% and 90% at 1 year, respectively (P < 0.001). Furthermore, patients with preoperative liver dysfunction had more embolic events and more re-explorations. At the 1-year follow-up, liver function markers showed an overall improvement in the majority of patients, with or without pre-LVAD liver dysfunction. CONCLUSIONS: Preoperative liver dysfunction is associated with higher early 90-day and 1-year mortality rates after LVAD implantation. Furthermore, liver function improved in both patient groups. It has become imperative to optimize the selection criteria for possible LVAD candidates, since those who survive the first year show excellent recovery of their liver markers.

Acute kidney injury following left ventricular assist device implantation: Contemporary insights and future perspectives.

Currently, an increasing number of patients with end-stage heart failure are being treated with left ventricular assist device (LVAD) therapy as bridge-to-transplantation, bridge-to-candidacy, or destination therapy (DT). Potential life-threatening complications may occur, specifically in the early post-operative phase, which positions LVAD implantation as a high-risk surgical procedure. Acute kidney injury (AKI) is a frequently observed complication after LVAD implantation and is associated with high morbidity and mortality. The rapidly growing number of LVAD implantations necessitates better approaches of identifying high-risk patients, optimizing peri-operative management, and preventing severe complications such as AKI. This holds especially true for those patients receiving an LVAD as DT, who are typically older (with higher burden of comorbidities) with impaired renal function and at increased post-operative risk. Herein we outline the definition, diagnosis, frequency, pathophysiology, and risk factors for AKI in patients with an LVAD. We also review possible strategies to prevent and manage AKI in this patient population.

Modification of a Ventricular Assistance Device for a Hemiplegic Left Ventricular Assist Device Patient.

Neurologic events occur in up to 18% of patients with continuous-flow left ventricular assist devices (LVAD) and is associated with significant morbidity and mortality. The current form of the LVAD equipment is not suited to serve patients who are impaired by a stroke. By creating an assistance device for the LVAD equipment, we have been able to greatly improve the quality of life and self-dependence of a hemiplegic LVAD patient.