Prevention of percutaneous driveline infection after left ventricular assist device implantation: prophylactic antibiotics are not necessary

Clinical impact of the use of chronic suppressive antibiotics against recurrent ventricular assist device infections

Ventricular assist device (VAD) infections are frequent causes of hospital readmission. The risk factors and optimal preventive strategies for such, including chronic suppressive antibiotics (CSA), remain uncertain. We performed a single-center, retrospective, observational cohort study assessing continuous flow VAD recipients who underwent implantation between 2008 and 2018 in Japan. From primary VAD infection (VADI), we followed the patients for recurrent infection, defined as relapsing VAD-specific (e.g., localized infections) or VAD-related (e.g., bacteremia) infections requiring hospital readmission. CSA was defined as the use of oral antimicrobial agents continued beyond initial antibiotic use until transplantation, VAD withdrawal, VADI recurrence, or death. Survival analysis was performed to identify risk factors for recurrent infection accounting for competing risks (e.g., deaths and transplants). Among 163 eligible patients, 76 patients had VADIs. The main causative organism in primary VADI was Staphylococcus aureus (63%, 48/76). Among them, 41 had recurrent infections, whereas 35 had none during the follow-up period (median, 335 days). Thirty-six patients received CSA for a median of 478 days. Although CSA was associated with a decreased risk of recurrent infection [adjusted sub-distribution hazard ratio (SHR), 0.40; 95% confidence interval (CI), 0.18-0.89; P = 0.03], this protective effect was observed only after primary VAD-specific infection (SHR, 0.28; 95% CI, 0.12-0.64; P < 0.01) but not after VAD-related infection. Surgical procedures during primary VADI were associated with an increased risk (SHR, 2.00; 95% CI, 1.10-3.66; P = 0.02). One patient had an adverse drug reaction. CSA may be an effective approach to limit relapsing VADIs following a primary VAD-specific infection with minimal adverse events.

IMPORTANCE

Ventricular assist device infections (VADIs) are a significant complication leading to hospital readmissions. However, the risk factors and optimal preventive strategies for VADI remain unclear. This study investigated the effectiveness of chronic suppressive antibiotic therapy in patients with VADI. We found that the use of chronic suppressive antibiotic therapy was associated with a reduction in the risk of VADI recurrence with few adverse reactions. Our findings suggest the potential benefit of chronic suppressive antibiotics in preventing infections in selected cases. Our findings are relevant for the management of patients with ventricular assist devices awaiting heart transplantation, providing valuable insights for clinical practice.

Soft and Hard Tissue Integration around Percutaneous Bone-Anchored Titanium Prostheses: Toward Achieving Holistic Biointegration

A holistic biointegration of percutaneous bone-anchored metallic prostheses with both hard and soft tissues dictates their longevity in the human body. While titanium (Ti) has nearly solved osseointegration, soft tissue integration of percutaneous metallic prostheses is a perennial problem. Unlike the firm soft tissue sealing in biological percutaneous structures (fingernails and teeth), foreign body response of the skin to titanium (Ti) leads to inflammation, epidermal downgrowth and inferior peri-implant soft tissue sealing. This review discusses various implant surface treatments/texturing and coatings for osseointegration, soft tissue integration, and against bacterial attachment. While surface microroughness by SLA (sandblasting with large grit and acid etched) and porous calcium phosphate (CaP) coatings improve Ti osseointegration, smooth and textured titania nanopores, nanotubes, microgrooves, and biomolecular coatings encourage soft tissue attachment. However, the inferior peri-implant soft tissue sealing compared to natural teeth can lead to peri-implantitis. Toward this end, the application of smart multifunctional bioadhesives with strong adhesion to soft tissues, mechanical resilience, durability, antibacterial, and immunomodulatory properties for soft tissue attachment to metallic prostheses is proposed.

Infections in Patients With Left Ventricular Assist Devices: Current State and Future Perspectives

Mechanical circulatory support is increasingly being used as bridge-to-transplant and destination therapy in patients with advanced heart failure. Technologic improvements have led to increased patient survival and quality of life, but infection remains one of the leading adverse events following ventricular assist device (VAD) implantation. Infections can be classified as VAD-specific, VAD-related, and non-VAD infections. Risk of VAD-specific infections, such as driveline, pump pocket, and pump infections, remains for the duration of implantation. While adverse events are typically most common early (within 90 days of implantation), device-specific infection (primarily driveline) is a notable exception. No diminishment over time is seen, with event rates of 0.16 events per patient-year in both the early and late periods postimplantation. Management of VAD-specific infections requires aggressive treatment and chronic suppressive antimicrobial therapy is indicated when there is concern for seeding of the device. While surgical intervention/hardware removal is often necessary in prosthesis-related infections, this is not so easily accomplished with VADs. This review outlines the current state of infections in patients supported with VAD therapy and discusses future directions, including possibilities with fully implantable devices and novel approaches to treatment.

Non-patient factors associated with infections in LVAD recipients: A scoping review

BACKGROUND

Infections are the most common complication in recipients of durable left ventricular assist devices (LVAD) and are associated with increased morbidity, mortality, and expenditures. The existing literature examining factors associated with infection in LVAD recipients is limited and principally comprises single-center studies. This scoping review synthesizes all available evidence related to identifying modifiable, non-patient factors associated with infections among LVAD recipients.

METHODS

Published studies were identified through searching 5 bibliographic databases: PubMed, Scopus, EMBASE, CINAHL, and Web of Science Core Collection. Inclusion criteria required examination of factors associated with infections among recipients of contemporary, implantable, continuous flow LVADs. Key study characteristics were extracted by 4 independent reviewers and current literature described narratively. The Systems Engineering Initiative for Patient Safety (SEIPS) model was used to develop a taxonomy for non-patient related factors (e.g., tasks, tools, technologies, organization, and environment) associated with infections following LVAD implantation. All analyses took place between February 2019 and May 2021.

FINDINGS

A total of 43 studies met inclusion criteria. The majority of included studies were observational (n = 37), single-center (n = 29), from the U.S. (n = 38), and focused on driveline infections (n = 40). Among the 22 evaluated sub-domains of non-patient related factors, only two: increasing center experience and establishing a silicone-skin interface at the driveline exit site, were identified as consistently being associated with a lower risk of infection.

CONCLUSION

This review identified 43 studies that described non-patient related factors associated with infection in LVAD recipients. Only two factors were consistently associated with lower infection risk in LVAD recipients: increasing experience and establishing a silicone-skin interface at driveline exit site. The large variability in reporting across multiple studied interventions limited the ability to discern their effectiveness.

Driveline Features as Risk Factor for Infection in Left Ventricular Assist Devices: Meta-Analysis and Experimental Tests

Background: Risk factors for driveline infection (DLI) in patients with left ventricular assist devices are multifactorial. The aim of this study was to analyze the correlation between mechanical driveline features and DLI occurrence. Methods: A meta-analysis was conducted that included studies reporting DLI rates at 6 months after implantation of any of three contemporary devices (HVAD with Pellethane or Carbothane driveline, HeartMate II, and HeartMate 3). Further, outer driveline diameter measurements and ex-vivo experimental three-point bending and torsion tests were performed to compare the stiffness of the four different driveline types. Results: 21 studies with 5,393 patients were included in the meta-analysis. The mean weighted DLI rates ranged from 7.2% (HeartMate II) to 11.9% (HeartMate 3). The HeartMate II driveline had a significantly lower maximal bending force (Loadmax) (4.52 ± 0.19 N) compared to the Carbothane HVAD (8.50 ± 0.08 N), the HeartMate 3 (11.08 ± 0.3 N), and the Pellethane HVAD driveline (15.55 ± 0.14 N) (p < 0.001). The maximal torque (Torquemax) of the HeartMate II [41.44 (12.61) mNm] and the Carbothane HVAD driveline [46.06 (3.78) mNm] were significantly lower than Torquemax of the Pellethane HVAD [46.06 (3.78) mNm] and the HeartMate 3 [95.63 (26.60) mNm] driveline (p < 0.001). The driveline of the HeartMate 3 had the largest outer diameter [6.60 (0.58) mm]. A relationship between the mean weighted DLI rate and mechanical driveline features (Torquemax) was found, as the the HeartMate II driveline had the lowest Torquemax and lowest DLI rate, whereas the HeartMate 3 driveline had the highest Torquemax and highest DLI rate. Conclusions: Device-specific mechanical driveline features are an additional modifiable risk factor for DLI and may influence clinical outcomes of LVAD patients.

Ventricular Assist Device Driveline Infection and Development of Intracranial Hemorrhage: A Case Series

Durable left ventricular assist devices (LVAD) are frequently complicated by driveline infection. The objective of this case series was to examine whether an association exists between driveline infection and intracranial hemorrhage. This retrospective case series included patients at a single tertiary care hospital on durable LVAD support who developed intracranial hemorrhage. Physical examination data, vital signs, and laboratory markers of sepsis including blood cultures and imaging of driveline sites were reviewed. A total of nine patients were included in the case series. At the time of hemorrhagic event, five patients had active driveline infection, and five patients were found to be bacteremic. All bacteremic patients were found to have supratherapeutic INR at the time of presentation. Although five patients experienced subarachnoid hemorrhage, only one patient was found to have a cerebral aneurysm. This case series highlights a possible association between LVAD driveline infection and intracranial hemorrhage, and the need for further research to better understand the pathophysiology driving this association.

Ventricular Assist Device Driveline Infections: A Systematic Review

Infection is the most common complication in patients undergoing ventricular assist device (VAD) implantation. Driveline exit site (DLES) infection is the most frequent VAD infection and is a significant cause of adverse events in VAD patients, contributing to morbidity, even mortality, and repetitive hospital readmissions. There are many risk factors for driveline infection (DLI) including younger age, smaller constitution of patients, obesity, exposed velour at the DLES, longer duration of device support, lower cardiac index, higher heart failure score, DLES trauma, and comorbidities such as diabetes mellitus, chronic kidney disease, and depression. The incidence of DLI depends also on the device type. Numerous measures to prevent DLI currently exist. Some of them are proven, whereas the others remain controversial. Current recommendations on DLES care and DLI management are predominantly based on expert consensus and clinical experience of the certain centers. However, careful and uniform DLES care including obligatory driveline immobilization, previously prepared sterile dressing change kits, and continuous patient education are probably crucial for prevention of DLI. Diagnosis and treatment of DLI are often challenging because of certain immunological alterations in VAD patients and microbial biofilm formation on the driveline surface areas. Although there are many conservative and surgical methods described in the DLI treatment, the only possible permanent solution for DLI resolution in VAD patients is heart transplantation. This systematic review brings a comprehensive synthesis of recent data on the prevention, diagnostic workup, and conservative and surgical management of DLI in VAD patients.

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.

Contemporary Management Strategies in VAD Infection

PURPOSE OF REVIEW

The use of durable ventricular assist devices (VAD) to manage end-stage heart failure is increasing, but infection remains a leading cause of morbidity and mortality among patients with VAD. In this review, we synthesize recent data pertaining to the epidemiology, diagnosis, management, and prevention of VAD infections, discuss transplant considerations in patients with VAD infections, and highlight remaining knowledge gaps. We also present a conceptual framework for treating clinicians to approach these infections that draws on the same principles that guide the treatment of analogous infections that occur in patients without VAD.

RECENT FINDINGS

Despite advances in device design, surgical techniques, and preventative interventions, more than a third of VAD recipients still experience infection as an adverse outcome. Positron emission tomography has emerged as a promising modality for identifying and characterizing VAD infections. High-quality data to support many of the routine therapeutic strategies currently used for VAD infections-including suppressive antibiotic therapy, surgical debridement/device exchange, and novel antimicrobials for emerging multidrug-resistant organisms-remain limited. Although pre-transplant VAD infection may impact some early transplant outcomes, transplantation remains a viable option for patients with most types of VAD infection. Standardized definitions of VAD infection applied to large registry datasets have yielded key insights into the epidemiology of infectious complications among VAD recipients, but more prospective studies are needed to evaluate the effectiveness of existing and novel diagnostic and therapeutic strategies.

Pharmacotherapy for durable left ventricular assist devices

Left ventricular assist devices (LVADs) have revolutionized the care of patients with advanced heart failure, yet still require concomitant medications in order to achieve the best possible clinical outcomes. Since the outset of routine placement of durable, continuous-flow LVADs, much of the medication management of these patients to date has been based on International Society of Heart and Lung Transplantation (ISHLT) guidance, most recently published in 2013. Since 2013, numerous multidisciplinary pharmacotherapy publications have increased the LVAD community's understanding of best practices with respect to medications. We identified the major domains of LVAD medication management and conducted a comprehensive search of US National Library of Medicine MEDLINE^® database using keywords chosen to identify medication-related publications of significance dated 2013 or later. Trials pertaining to the HeartMate II™ and the HeartMate™ 3 LVADs (Abbott, Chicago, IL) and the HeartWare™ HVAD™ System (Medtronic, Minneapolis, MN) were chosen for inclusion. Highest priority for inclusion was given to prospective, randomized, controlled studies. Absent these, controlled trials (retrospective or prospective observational) were given next-highest consideration, followed by retrospective uncontrolled studies, and finally case series. Reference lists of qualified publications were reviewed to find any other publications of interest that were not discovered on initial search. Case reports were generally excluded, except where the insight gained was deemed to be uniquely pertinent. This document serves to provide a comprehensive review of the current understanding of optimal medication management in patients with durable, continuous-flow LVADs.

Ventricular Assist Device-Specific Infections

Ventricular assist device (VAD)-specific infections, in particular, driveline infections, are a concerning complication of VAD implantation that often results in significant morbidity and even mortality. The presence of a percutaneous driveline at the skin exit-site and in the subcutaneous tunnel allows biofilm formation and migration by many bacterial and fungal pathogens. Biofilm formation is an important microbial strategy, providing a shield against antimicrobial treatment and human immune responses; biofilm migration facilitates the extension of infection to deeper tissues such as the pump pocket and the bloodstream. Despite the introduction of multiple preventative strategies, driveline infections still occur with a high prevalence of ~10-20% per year and their treatment outcomes are frequently unsatisfactory. Clinical diagnosis, prevention and management of driveline infections are being targeted to specific microbial pathogens grown as biofilms at the driveline exit-site or in the driveline tunnel. The purpose of this review is to improve the understanding of VAD-specific infections, from basic "bench" knowledge to clinical "bedside" experience, with a specific focus on the role of biofilms in driveline infections.

In vitro Evaluation of Medihoney Antibacterial Wound Gel as an Anti-biofilm Agent Against Ventricular Assist Device Driveline Infections

Objectives: In adult ventricular assist device (VAD) programs in Australian hospitals, Medihoney Antibacterial Wound Gel (MAWG) is routinely used at the skin exit-site of VAD drivelines to prevent infections; however, its effectiveness remains unclear. Our aim was to assess antimicrobial activity of Medihoney wound gel, using in vitro models that mimic clinical biofilms grown at the driveline exit-site. Methods: Antimicrobial susceptibility testing of MAWG was performed for 24 clinical isolates grown under planktonic conditions, and four representative strains grown as biofilms. Different antimicrobial mechanisms of MAWG were assessed respectively for their relative contribution to its anti-biofilm activity. A colony biofilm assay and a drip-flow biofilm reactor assay mimicking the driveline exit-site environment were used to evaluate the activity of MAWG against biofilm growth at the driveline exit-site. Results: MAWG demonstrated species-specific activity against planktonic cultures [minimum inhibitory concentrations (MICs), 5-20% weight/volume (W/V) for Staphylococcus species, 20->40% (W/V) for Pseudomonas aeruginosa and Candida species]. Higher concentrations [MICs, 30->80% (W/V)] were able to inhibit biofilm growth, but failed to eradicate pre-established biofilms. The anti-biofilm properties of MAWG were multi-faceted, with the often-advertised "active" ingredient methylglyoxal (MGO) playing a less important role. The colony biofilm assay and the drip-flow biofilm reactor assay suggested that MAWG was unable to kill biofilms pre-established in a driveline exit-site environment, or effectively prevent planktonic cells from forming adherent monolayers and further developing mature biofilms. Conclusion: Our work suggests a suboptimal effectiveness of MAWG in preventing driveline infections due to biofilm development.

Characterization of infected, explanted ventricular assist device drivelines: The role of biofilms and microgaps in the driveline tunnel

BACKGROUND

Driveline infections remain a major complication of ventricular assist device (VAD) implantation. This study aimed to characterize in vivo microbial biofilms associated with driveline infections and host tissue integration of implanted drivelines.

METHODS

A total of 9 infected and 13 uninfected drivelines were obtained from patients with VAD undergoing heart transplantation in Australia between 2016 and 2018. Each driveline was sectioned into 11 pieces of 1.5 cm in length, and each section was examined by scanning electron microscopy (SEM) and viable counts for microbial biofilms. Microorganisms were cultured and identified. Host tissue integration of clinical drivelines was assessed with micro-computed tomography (CT) and SEM. An in vitro interstitial biofilm assay was used to simulate biofilm migration in the driveline tunnel, and time-lapse microscopy was performed.

RESULTS

Of the 9 explanted, infected drivelines, all had organisms isolated from varying depths along the velour section of the drivelines, and all were consistent with the swab culture results of the clinically infected exit site. SEM and micro-CT suggested insufficient tissue integration throughout the driveline velour, with microgaps observed. Clinical biofilms presented as microcolonies within the driveline tunnel, with human tissue as the sub-stratum, and were resistant to anti-microbial treatment. Biofilm migration mediated by a dispersal-seeding mechanism was observed.

CONCLUSIONS

This study of explanted infected drivelines showed extensive anti-microbial-resistant biofilms along the velour, associated with microgaps between the driveline and the surrounding tissue. These data support the enhancement of tissue integration into the velour as a potential preventive strategy against driveline infections by preventing biofilm migration that may use microgaps as mediators.

In Full Flow: Left Ventricular Assist Device Infections in the Modern Era

With the rising prevalence of heart disease in the United States, there is increasing reliance on durable mechanical circulatory support (MCS) to treat patients with end-stage heart failure. Left ventricular assist devices (LVADs), the most common form of durable MCS, are implanted mechanical pumps that connect to an external power source through a transcutaneous driveline. First-generation LVADs were bulky, pulsatile pumps that were frequently complicated by infection. Second-generation LVADs have an improved design, though infection remains a common and serious complication due to the inherent nature of implanted MCS. Infections can affect any component of the LVAD, with driveline infections being the most common. LVAD infections carry significant morbidity and mortality for LVAD patients. Therefore, it is paramount for the multidisciplinary team of clinicians caring for these patients to be familiar with this complication. We review the epidemiology, prevention, diagnosis, treatment, and outcomes of LVAD infections.

VAD infection during bridge-to-transplant, unique aspects of treatment and prevention

PURPOSE OF REVIEW

VAD infections remain a frequent complication of VAD care and can markedly affect patient management before and after transplantation. This review highlights the standard-of-care approaches offered by recent guidelines as well as published data that may improve the care for patients with these challenging and often persistent infections.

RECENT FINDINGS

Prevention and management of VAD infections has become more standardized with updated consensus guidelines published in 2017. Unfortunately, advanced devices have not markedly affected the incidence of VAD infection. Efforts to improve, yet streamline, the prevention of VAD-specific infections are ongoing. However, the data provided in the best of recent publications are rarely effectively comparative. Granular data on management strategies are limited to a few studies. Nevertheless, several publications provide more detailed posttransplant outcomes for patients with pretransplant VAD infections and demonstrate overall excellent posttransplant survival.

SUMMARY

Prevention and management of VAD-specific and VAD-related infections are the ongoing work of all VAD programs. Consensus guidelines are a marker of progress for this field. Despite very good posttransplant outcomes for these patients, more granular data are required to understand how such patients arrive successfully to transplantation and how their posttransplant course is affected.

Single versus multi-drug antimicrobial surgical infection prophylaxis for left ventricular assist devices: A systematic review and meta-analysis

Infection remains the Achilles heel of left ventricular assist device (LVAD) therapy. However, an optimal antimicrobial surgical infection prophylaxis (SIP) regimen has not been established. This study evaluated the efficacy of a single-drug SIP compared to a multi-drug SIP on clinical outcomes in patients undergoing continuous-flow LVAD (CF-LVAD) and pulsatile LVAD (P-LVAD) implantation. An electronic search was performed to identify studies in the English literature on SIP regimens in patients undergoing LVAD implantation. Identified articles were assessed for inclusion and exclusion criteria. Fourteen articles with 1,311 (CF-LVAD: 888; P-LVAD: 423) patients were analyzed. Overall, 501 (38.0%) patients received single-drug SIP, whereas 810 (62.0%) received multi-drug SIP. Time to infection was comparable between groups. There was no significant difference in overall incidence of LVAD-specific infections [single-drug: 18.7% vs. multi-drug: 24.8%, P = 0.49] including driveline infections [single-drug: 14.1% vs. multi-drug: 20.8%, P = 0.37]. Compared to single-drug SIP, patients who received multi-drug SIP had a significantly lower survival rate [single-drug: 90.0% vs. multi-drug: 76.0%, P = 0.01] and infection-free survival rate [single-drug: 88.4% vs. multi-drug: 77.3%, P = 0.04] at 90 days. However, there were no significant differences in 1-year survival and 1-year infection-free survival between groups. No survival differences were observed in the CF-LVAD subset as well. This study demonstrated no additional advantage of a multi-drug compared to a single-drug regimen for SIP. Although there was a modest advantage in early survival among CF-LVAD and P-LVAD patients who received single-drug SIP, there were no significant differences in the 1-year survival and 1-year infection-free survival.

Left Ventricular Assist Device Infections: A Systematic Review

Left ventricular assist devices (LVADs) are becoming a more frequent life-support intervention. Gaining an understanding of risk factors for infection and management strategies is important for treating these patients. We conducted a systematic review and meta-analysis of studies describing infections in continuous-flow LVADs. We evaluated incidence, risk factors, associated microorganisms, and outcomes by type of device and patient characteristics. Our search identified 90 distinct studies that reported LVAD infections and outcomes. Younger age and higher body mass index were associated with higher rates of LVAD infections. Driveline infections were the most common infection reported and the easiest to treat with fewest long-term consequences. Bloodstream infections were not reported as often, but they were associated with stroke and mortality. Treatment strategies varied and did not show a consistent best approach. LVAD infections are a significant cause of morbidity and mortality in LVAD patients. Most research comes from secondary analyses of other LVAD studies. The lack of infection-oriented research leaves several areas understudied. In particular, bloodstream infections in this population merit further research. Providers need more research studies to make evidence-based decisions about the prevention and treatment of LVAD infections.

Driveline Site Is Not a Predictor of Infection After Ventricular Assist Device Implantation

Driveline infections (DLIs) remain a major source of morbidity for patients requiring long-term ventricular assist device (VAD) support. We aimed to assess whether VAD driveline exit site (DLES) (abdomen versus chest wall) is associated with DLI. All adult patients who underwent insertion of a HeartWare HVAD or HeartMate II (HMII) between 2009 and 2016 were included. Driveline infection was defined as clinical evidence of DLI accompanied by a positive bacterial swab and need for antibiotics. Competing risks analysis was used to assess the association between patient characteristics and DLI. Ninety-two devices (59 HMII) were implanted in 85 patients (72 men; median age 57.4 years) for bridge to transplant or destination therapy. VAD DLES was chest in 28 (30.4%) devices. Median time on VAD support was 347.5 days (IQR 145.5, 757.5), with 28 transplants and 29 deaths (27 on device). DLI occurred in 24 patients (25 devices) at a median of 140 days (IQR 67, 314) from implant. Staphylococcus aureus accounted for 15 infections (60%). Freedom from infection was 72.8% (95% confidence interval [CI] 53.1-78.0%) at 1 year and 41.9% (95% CI 21.1-61.5%) at 3 years. In competing risks regression, abdominal DLES was not predictive of DLI (hazard ratio, HR 1.65 [95% CI 0.63, 4.29]), but body mass index (BMI) >30 kg/m was (HR 2.72 [95% CI 1.25, 5.92]). In conclusion, risk of DLI is high among patients on long-term VAD support, and a nonabdominal DLES does not reduce this risk. The only predictor of DLI in this series was an elevated BMI.

Risk of left ventricular assist device driveline infection: A systematic literature review

BACKGROUND

Left ventricular assist devices (LVADs) improve quality of life in end-stage heart failure but can cause serious complications such as infections with driveline infection causing significant morbidity and mortality.

OBJECTIVES

The purpose of this systematic literature review is to synthesize the literature to determine variables associated with driveline infection and seek opportunities to improve nursing management of LVAD drivelines.

METHODS

A systematic literature review was performed. The evidence was synthesized using the Johns Hopkins Nursing Evidence-Based Practice tools and the Chain of Infection epidemiological framework.

RESULTS

Thirty-four studies focused on vulnerable host, portal of entry, and causative organism aspects of the Chain of Infection. Increased BMI, younger age, exposed driveline velour showed increased risk of infection and driveline dressing protocol change showed lower risk of infection.

CONCLUSIONS

Although some risk factors for infection were identified, evidence is still limited. Nurses are uniquely positioned to improve driveline management, disrupting the chain of infection.

Ventricular Assist Device Infections

This article reviews the diagnostic criteria for ventricular assist device (VAD) infection, pathogenesis, and microbiology as well as the diagnostic pathway when patients present with signs and symptoms concerning for VAD infection. Recommendations regarding infection prevention and management are reviewed as well.

Current State and Future Perspectives of Energy Sources for Totally Implantable Cardiac Devices

There is a large population of patients with end-stage congestive heart failure who cannot be treated by means of conventional cardiac surgery, cardiac transplantation, or chronic catecholamine infusions. Implantable cardiac devices, many designated as destination therapy, have revolutionized patient care and outcomes, although infection and complications related to external power sources or routine battery exchange remain a substantial risk. Complications from repeat battery replacement, power failure, and infections ultimately endanger the original objectives of implantable biomedical device therapy - eliminating the intended patient autonomy, affecting patient quality of life and survival. We sought to review the limitations of current cardiac biomedical device energy sources and discuss the current state and trends of future potential energy sources in pursuit of a lifelong fully implantable biomedical device.

Driveline Infection Risk with Utilization of a Temporary External Anchoring Suture After Implantation of a Left Ventricular Assist Device

Driveline infections (DLI) are a cause of morbidity after continuous-flow left ventricular assist device (CF-LVAD) implantation. Because driveline trauma contributes to DLI, we assessed whether intraoperative placement of a temporary external anchoring suture (EAS) influenced DLI rate. We analyzed 161 consecutive patients with CF-LVAD (HMII 82; HW 79) implantation. Two groups were defined: placement of EAS (n = 85) or No EAS (n = 76). For NO EAS patients, the driveline was permanently anchored internally to the rectus fascia. Cox proportional analysis was performed to assess the effect of EAS on time to first confirmed DLI. Baseline characteristics were comparable between groups (all p = 0.3). Mean follow-up time was 0.93 years. A total of 18 (11.1%) patients developed confirmed culture positive DLI, with "first infection" rate of 0.13 events/year. Mean time to confirmed DLI was 0.69 years. Driveline infection was less likely (hazard ratio [HR] = 0.28, 0.95 confidence interval [CI] = 0.06-1.25, p = 0.056) to occur in NO EAS (2/18) then in EAS (16/18). Confirmed DLI was comparable between device types (p = 0.3). Multivariable regression adjusted for age, BMI, blood product use, device type, and diabetes showed equivocal effect of EAS (HR = 0.33, 0.95 CI = 0.07-1.54, p = 0.12). Patients with a temporary EAS may have an increased risk of confirmed DLI after device implantation.

Chronic outpatient management of patients with a left ventricular assist device

The use of mechanical circulatory support (MCS) as treatment for advanced heart failure (HF) has grown exponentially over the past 15 years. The continuous flow left ventricular assist device (CF-LVAD) has become the most used form of MCS in advanced HF, especially since approval of use as destination therapy (DT) and with the lack of organ availability. Long-term survival has improved and diligent outpatient management is thus particularly critical to achieve optimal outcomes. This review will discuss outpatient management strategies for patients with HF and a left ventricular assist device (LVAD).

A review of infections in patients with left ventricular assist devices: prevention, diagnosis and management

Since the advent of ventricular assist devices with smaller configurations and continuous-flow technology, survival rates for patients with end-stage heart failure have dramatically improved. While the burden of infectious complications is decreased in patients on continuous-flow ventricular assist devices compared to bulkier pulsatile-flow devices, infection remains one of the most common causes of morbidity and mortality. The majority of infections occur at the driveline exit site, beginning with a disruption or trauma to the barrier between the skin and driveline and sometimes spreading deeper. Once infections develop, they can be difficult to eradicate. Depending on the degree of infection, treatment options may include local wound care, antibiotics, or surgical treatment. Preventive strategies and careful surveillance are crucial to improve patient outcomes.

Left Ventricular Assist Device Driveline Infections

Heart failure is a chronic progressive disease that affects millions of people in the United States. Although medical management of heart failure has helped improve quality of life and survival, end-stage heart failure ultimately requires a heart transplant or long-term left ventricular assist device (LVAD) support. With more patients awaiting transplant, the demand for hearts outweighs the supply of donor hearts. The use of LVADs is increasing in patients with advanced heart failure as a treatment option for those awaiting a heart transplant or as a long-term solution if they are ineligible for a transplant. Although the LVAD is a marvel of modern medicine, infection is a cause of concern because today’s LVADs are powered externally through a percutaneous driveline that can be a major source of infection.