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

Mechanical Characterization of Anchoring Devices for the Prevention of Driveline Infection in Left Ventricular Assist Device Patients

Driveline infection (DLI) is associated with increased mortality and morbidity in left ventricular assist device (LVAD) patients. Because trauma to the driveline exit-site (DLES) is a risk factor for DLI, adhesive anchoring devices are used to immobilize the DL. In this study, commonly used products (identified through literature review and contact with nine international VAD implantation centers) were mechanically characterized to evaluate their effectiveness in preventing DLES trauma. Eight devices were tested in an in vitro abdominal model of the DLES, where a tensile force (10 N) was applied to a HeartMate 3 DL, whereas the resulting force ( FTotal ) on the DLES was recorded using a three-axis load cell. Four devices (CathGrip: FTotal = 2.1 ± 0.4 N, Secutape: FTotal = 2.6 ± 0.3 N, Hollister: FTotal = 2.7 ± 0.5 N, Tubimed: FTotal = 2.9 ± 0.2 N) were significantly ( p < 0.05) better at preventing tensile forces at the DLES compared to the other four devices (Main-Lock: FTotal = 3.7 [0.7] N, Secutape sensitive: FTotal = 3.9 ± 0.4 N, Foley Anchor: FTotal = 4.3 ± 0.5 N, Grip-Lok: FTotal = 5.4 ± 0.8 N). Immobilization of the DL with each anchoring device resulted in lower tensile force on the DLES than without an anchor ( FTotal = 8.2 ± 0.3 N). In conclusion, the appropriate selection of anchoring devices plays a critical role in reducing the risk of DLI, whereas the CathGrip, Secutape, Hollister, or Tubimed were superior in preventing trauma to the DLES in this study.

Advanced Heart Failure: Therapeutic Options and Challenges in the Evolving Field of Left Ventricular Assist Devices

Heart Failure is a chronic and progressively deteriorating syndrome that has reached epidemic proportions worldwide. Improved outcomes have been achieved with novel drugs and devices. However, the number of patients refractory to conventional medical therapy is growing. These advanced heart failure patients suffer from severe symptoms and frequent hospitalizations and have a dismal prognosis, with a significant socioeconomic burden in health care systems. Patients in this group may be eligible for advanced heart failure therapies, including heart transplantation and chronic mechanical circulatory support with left ventricular assist devices (LVADs). Heart transplantation remains the treatment of choice for eligible candidates, but the number of transplants worldwide has reached a plateau and is limited by the shortage of donor organs and prolonged wait times. Therefore, LVADs have emerged as an effective and durable form of therapy, and they are currently being used as a bridge to heart transplant, destination lifetime therapy, and cardiac recovery in selected patients. Although this field is evolving rapidly, LVADs are not free of complications, making appropriate patient selection and management by experienced centers imperative for successful therapy. Here, we review current LVAD technology, indications for durable MCS therapy, and strategies for timely referral to advanced heart failure centers before irreversible end-organ abnormalities.

Anti-infective characteristics of a new Carbothane ventricular assist device driveline

Objectives

Driveline infections are a major complication of ventricular assist device (VAD) therapy. A newly introduced Carbothane driveline has preliminarily demonstrated anti-infective potential against driveline infections. This study aimed to comprehensively assess the anti-biofilm capability of the Carbothane driveline and explore its physicochemical characteristics.

Methods

We assessed the Carbothane driveline against biofilm formation of leading microorganisms causing VAD driveline infections, including Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Candida albicans, using novel in vitro biofilm assays mimicking different infection micro-environments. The importance of physicochemical properties of the Carbothane driveline in microorganism-device interactions were analyzed, particularly focusing on the surface chemistry. The role of micro-gaps in driveline tunnels on biofilm migration was also examined.

Results

All organisms were able to attach to the smooth and velour sections of the Carbothane driveline. Early microbial adherence, at least for S. aureus and S. epidermidis, did not proceed to the formation of mature biofilms in a drip-flow biofilm reactor mimicking the driveline exit site environment. The presence of a driveline tunnel however, promoted staphylococcal biofilm formation on the Carbothane driveline. Physicochemical analysis of the Carbothane driveline revealed surface characteristics that may have contributed to its anti-biofilm activity, such as the aliphatic nature of its surface. The presence of micro-gaps in the tunnel facilitated biofilm migration of the studied bacterial species.

Conclusion

This study provides experimental evidence to support the anti-biofilm activity of the Carbothane driveline and uncovered specific physicochemical features that may explain its ability to inhibit biofilm formation.

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.

Total Joint Arthroplasty in Patients With an Implanted Left Ventricular Assist Device

Left ventricular assist devices (LVADs) may be used as bridge therapy or destination therapy in heart failure patients. Total joint arthroplasty may improve the functional status of patients limited by arthritis. This retrospective case series evaluated patients with an implanted LVAD who underwent a total joint arthroplasty at 1 institution from 2012 to present. Five patients underwent 12 surgeries with 7 primary arthroplasties and 5 revisions. Their mortality, length of stay, coagulopathic events, incidence of infection or revision arthroplasty, and heart transplantation were evaluated, and is the largest study to date of this population. Two patients expired from thrombotic events while 3 progressed to heart transplantation. Joint arthroplasty is feasible in patients with an implanted LVAD with expected risk and perioperative multidisciplinary collaboration.

Oncostatin M: a Potential Biomarker to Predict Infection in Patients with Left Ventricular Assist Devices

Infection is a serious adverse event limiting left ventricular assist device (LVAD) therapy in advanced heart failure patients, but a reliable means to identify patients at increased risk of infection is still lacking. We hypothesized that preoperative elevated levels of plasma Oncostatin M (OSM), a cytokine marker of leukocyte activation and inflammation, would be predictive of subsequent infection. We measured plasma OSM in 41 LVAD patients one day before LVAD implantation and postoperatively over two months. Preoperative plasma OSM levels were normal in 27 patients (group A, 4.9 ± 3.2 pg/ml) but elevated in 14 patients (group B, 1649.0 ± 458.9 pg/ml) ( p = 0.003). Early postoperative levels rose in both groups and declined rapidly in group A, with group B declining slowly over two months. Significantly more infections developed in group B than group A patients over two months postimplantation ( p = 0.004). No other routine clinical assessment or laboratory testing afforded this differentiation. These findings suggest that preoperative plasma OSM levels may assist in identifying patients at increased risk of infections after LVAD implantation.

Infections in LVAD patients

Infections in LVAD patients continue to be a major cause of morbidity and mortality. One needs to separate between early infections which are mostly driven by the general state of the patient before implant, and infections during long term support, mostly related to drive line issues. A diligent risk stratification before implant and close follow up after implant will help to reduce the incidence of infection.

Infections in LVAD patients

Infections in left ventricular assist device (LVAD) patients remain common. Differentiating into device related and non-device related infection is crucial. The incidence of non-device related infections seems to be more determined by the overall condition of the LVAD recipient. Device related infections can be treated by innovative surgical approaches or by transplant. Infection increases the risk of mortaility while on LVAD.

Decreasing driveline infections in patients supported on ventricular assist devices: a care pathway approach

Background

Driveline infections (DLIs) are a common adverse event in patients on ventricular assist devices (VADs) with incidence ranging from 14% to 59%. DLIs have an impact on patients and the healthcare system with efforts to prevent DLIs being essential. Prior to our intervention, our program had no standard driveline management presurgery and postsurgery. The purpose of this Quality Improvement (QI) initiative was to reduce DLIs and related admissions among patients with VAD within the first year post implant.

Methods

In anticipation of the QI project, we undertook a review of the programs’ current driveline management procedures and completed a survey with patients with VAD to identify current barriers to proper driveline management. Retrospective data were collected for a pre-QI intervention baseline comparison group, which included adult patients implanted with a durable VAD between 1 January 2017 and 31 July 2018. A three-pronged care pathway (CP) was initiated among patients implanted during August 2018 to July 2019. The CP included standardised intraoperative, postoperative and predischarge teaching initiatives and tracking. Using statistical process control methods, DLIs and readmissions in the first year post implant were compared between patients in the CP group and non-CP patients. P-charts were used to detect special cause variation.

Results

A higher proportion of CP group patients developed a DLI in the first year after implant (52% vs 32%). None developed a DLI during the index admission, which differed from the non-CP group and met criteria for special cause variation. There was a downward trend in cumulative DLI-related readmissions among CP group patients (55% vs 67%). There was no association between CP compliance and development of DLIs within 1 year post implant.

Conclusion

The CP did not lead to a reduction in the incidence of DLIs but there was a decrease in the proportion of patients with DLIs during their index admission and those readmitted for DLIs within 1 year post implant. This suggests that the CP played a role in decreasing the impact of DLIs in this patient population. However, given the short time period of follow-up longer follow-up will be required to look for sustained effects.

Impact of Right Heart Failure on Clinical Outcome of Left Ventricular Assist Devices (LVAD) Implantation: Single Center Experience

The aim of this study was to examine the incidence and significance of right heart failure (RHF) in the early and late phase of left ventricular assist device (LVAD) implantation with the identification of predictive factors for the development of RHF. This was a prospective observational analytical cohort study. The study included 92 patients who underwent LVAD implantation and for whom all necessary clinical data from the follow-up period were available, as well as unambiguous conclusions by the heart team regarding pathologies, adverse events, and complications. Of the total number of patients, 43.5% died. The median overall survival of patients after LVAD implantation was 22 months. In the entire study population, survival rates were 88.04% at one month, 80.43% at six months, 70.65% at one year, and 61.96% at two years. Preoperative RHF was present in 24 patients, 12 of whom died and 12 survived LVAD implantation. Only two survivors developed early RHF (ERHF) and two late RHF (LRHF). The most significant predictors of ERHF development are brain natriuretic peptide (BNP), pre-surgery RHF, FAC < 20%, prior renal insufficiency, and total duration of ICU stay (HR: 1.002, 0.901, 0.858, 23.554, and 1.005, respectively). RHF following LVAD implantation is an unwanted complication with a negative impact on treatment outcome. The increased risk of fatal outcome in patients with ERHF and LRHF after LVAD implantation results in a need to identify patients at risk of RHF, in order to administer the available preventive and therapeutic methods.

Significance of right ventricular function for the outcome of treatment and remodeling of the heart after left ventricular assist device implantation

The efficiency of the device for permanent circulatory support of the left ventricle has been proven through clinical practice with the trend of constant improvement of treatment results along with biotechnological progress and improvement of surgical implantation techniques. The published reports of most reference cardiac surgery centers present a one-year survival rate of over 85%, a two-year survival rate of 70% and a five-year survival rate of 45-50%. In addition to clear benefits for the patient, implantation of LVAD also carries significant specific risks, so infections, post-implantation bleeding, strokes, and right ventricular postimplantation weakness are the most common complications. Given that the progress of the LVAD program is ensured primarily by reducing the incidence of complications not related to the functioning of individual segments of the cardiovascular system, and as left ventricular function is completely replaced by LVAD device, the most recent challenge is the decision to install LVAD device in the heart with right ventricular, given that the postimplantation weakness of right ventricular is associated with proven increased mortality and morbidity. Since the 1990s, studies on hearts with implanted LVAD as a bridge to heart transplantation have shown regression of cell hypertrophy, normalization of cell size, muscle fiber architecture, and heart chamber geometry. The described changes are characterized by the notion of reverse remodeling, which is synonymous with function recovery. It is this process at the level of the right ventricle that is recognized as extremely important for the success of LVAD programs, especially in the group of patients who have a certain degree of right ventricular weakness preoperatively. The basic requirements of the cardiac surgery team are adequate preoperative assessment of right ventricular weakness, then application of measures to prevent damage and load on the right ventricle during and after LVAD implantation, as well as providing adequate therapeutic measures for right ventricular recovery in the postimplantation period.

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.

Characteristics and Outcomes of Left Ventricular-Assist Device-Associated Cerebrovascular Events in Setting of Infectious Intracranial Aneurysms

Background and purpose: The study aims to identify the characteristics and neurological outcomes of the left ventricular-assist device (LVAD)-associated cerebrovascular events (CVE) and infections, particularly in the setting of infectious intracranial aneurysms (IIA).

Methods: A single-center retrospective review of patients having undergone LVAD implantation between 2011 and 2017 was conducted using institutional registries and screened for CVE. Patients with CVE were assessed for concurrent bacteremia; neurovascular imaging was then used to isolate patients with IIA. A review of comorbidities, imaging characteristics, and management were performed to determine predictors of neurological outcomes, as defined by the 90-day modified Rankin scale (mRS) scores.

Results: Of the 383 HeartMate II LVAD implantations performed, 43 all-cause stroke events were identified across 35 (9%) patients. The majority of the events were hemorrhagic CVE (n=28) with 21 events complicated by bacteremia. Of patients with hemorrhagic CVE and bacteremia, Staphylococcus aureus (n=10) and Pseudomonas aeruginosa (n= 8) infection were the most frequently associated organisms. Severe disability or death (90-day mRS > 4) was observed in 15 patients (63%). Seven patients had confirmed findings of IIA on diagnostic cerebral angiogram and were associated with distal middle cerebral artery (MCA) territory involvement (n=6; 86%) with concurrent Staphylococcus (n=5, 71%) and/or Pseudomonas (n=4, 57%) infections. Overall, a higher incidence of acute and chronic bacteremia was observed in the hemorrhagic CVE subgroup compared to the ischemic CVE subgroup (74% vs 36% & 71% vs 29%, respectively; p <0.05). Despite endovascular and/or surgical intervention in patients with IIA, four patients failed management and elected for comfort measures.

Conclusion: Our results indicate that P. aeruginosa and S. aureus bacteremia are associated with a greater incidence of intracranial hemorrhage and worse neurological outcomes. Future management considerations may include pre-implantation cerebrovascular imaging to assess vascular pathology including prior aneurysms and intracranial atherosclerotic disease burden as a screen for higher-risk patients, as well as more aggressive antibiotic therapy at bacteremia onset.

The Joint Association of Septicemia and Cerebrovascular Diseases with In-Hospital MortalityAmong Patients with Left Ventricular Assist Device in the United States

OBJECTIVES

Left ventricular assist device (LVAD) is associated with complications such as cerebrovascular diseases (CEVD) as well as septicemia which is often preventable. With their use increasing in the U.S., identifying patients with LVAD who are at high risk for short-term mortality is essential for targeted effective patient management strategies to prevent adverse outcomes. We investigated the individual and joint association of CEVD and septicemia with the risk of in-hospital mortality in patients with LVAD in the U.S.

MATERIALS AND METHODS

We used data from the National Inpatient Sample from 2004 to 2015 to identify patients ≥18 years of age who underwent LVAD implantation by means of International Classification of Disease, 9th Revision, codes. Multivariable hierarchical negative binomial regression models were used to estimate risk ratios (RR) and 95% confidence intervals (CI) for in-hospital mortality by CEVD-septicemia status.

RESULTS

The mean age of the 4638 patients was 56 years, and 23% of them were women. Approximately 13% of patients had septicemia; 7% had CEVD and 2% had both conditions. In models adjusted for demographic, lifestyle/behavior factors and comorbid conditions, the risk of in-hospital mortality was almost threefold higher among patients with septicemia alone (RR=2.84, CI:2.24-3.60); two-and-half fold higher among patients with CEVD alone (RR=2.53, CI:1.85-3.48); and almost fourfold among patients with both septicemia and CEVD (RR=3.76, CI: 2.38-5.94, P_interaction = <0.001) CONCLUSION: The presence of both septicemia and CEVD was associated with a substantially higher risk of in-hospital mortality among LVAD patients when compared to septicemia or CEVD alone.

Intracranial Mycotic Aneurysm in a Left Ventricular Assist Device Patient: A Complication to Avoid

In the current era of the increasing use of left ventricular assist devices (LVADs) as a bridge to transplant or destination therapy, early diagnosis and therapy of complications are imperative to provide a better quality of life and improve outcomes. This case illustrates how superficial infections can lead to drastic complications in the setting of LVADs. The lack of signs and symptoms of systemic inflammatory response could be explained by cellular immunity impairment in patients on LVAD support. The formation of aneurysms is enhanced in the LVAD population due to altered hemodynamic physiology. It is possible that the combination of impaired cellular immunity and altered hemodynamics of the present-day continuous flow LVADS increases the risk of mycotic aneurysm formation and rupture in patients infected with less virulent organisms.

Reduction of Postoperative Infections Through Routine Preoperative Universal Decolonization of Advanced Heart Failure Patients With Chlorhexidine and Mupirocin Before Left Ventricular Assist Device Implantation: A Single-Center Observational Study

BACKGROUND

Left ventricular assist devices (LVADs) are increasingly being used in patients with advanced heart failure as bridge to transplant, bridge to decision, or destination therapy. Infections are a major complication associated with LVADs. Staphylococcus aureus is one of the common causative organisms associated with LVAD infections. Methicillin resistant staphylococcus aureus (MRSA)-colonized patients are at an increased risk for developing MRSA-associated infections. Various studies have demonstrated decolonization of skin with topical chlorhexidine and nares with 2% intranasal mupirocin ointment is effective in reducing MRSA-associated infections.

OBJECTIVE

The objective of this observational study was to examine the impact of a universal decolonization protocol using topical chlorhexidine and intranasal mupirocin ointment for 5 days before LVAD implantation on postoperative infections (30, 60, and 90 days) and 30-day infection-related rehospitalization.

METHODS

A preoperative universal decolonization with 4% chlorhexidine daily whole-body bath and 2% intranasal mupirocin ointment twice a day for 5 days was implemented for patients undergoing elective LVAD implantation. Using an observational study design, we included a convenience sample of 84 subjects who were established patients in an accredited advanced heart failure program. Thirty-seven patients served in the standard protocol group, and 47 in the universal decolonization protocol group participated in the observational study.

RESULTS

In the standard protocol group, there were 4 MRSA infections with none in the universal decolonization group (χ = 5.34, P = .03). In total, there were 8 surgical site infections in the standard protocol group and 1 in the universal decolonization group (χ = 5.95, P = .01).

CONCLUSION

A 5-day universal decolonization protocol before LVAD implantation was effective in reducing total infections as well as MRSA-specific infections.

Absorbable antibiotic beads as an adjuvant therapy in treating ventricular assist devices driveline infection: A case report

BACKGROUND

Ventricular assist devices driveline infections are common, recalcitrant, and carry high morbidity and mortality. Herein, we reported a patient with driveline infection that was successfully treated with a combination of systemic antibiotics, surgical debridement, and instillation of absorbable antibiotic beads to the wound bed.

METHODS AND RESULTS

A 39-year-old man with nonischemic cardiomyopathy underwent insertion of a continuous flow left ventricular assist device. Four years postoperatively, the patient presented with clinical, laboratory, and radiologic signs of driveline tract infection. He underwent extensive surgical debridement, installation of absorbable antibiotic beads that consisted of calcium sulfate, vancomycin, and tobramycin, into the wound bed, and systemic antibiotics. The patient was free of infection 9 month postoperatively.

CONCLUSION

Absorbable calcium sulfate antibiotic beads may serve as a beneficial adjunct to surgical debridement and systemic antibiotics for the treatment of ventricular assist device driveline infection, and merit further investigation.

Left ventricular assist device-associated infections: incidence and risk factors

Background

Left ventricular assist device (LVAD)-associated infections are major complications that can lead to critical outcomes. The aims of this study were to assess the incidence of and to determine the risk factors for LVAD-associated infections.

Methods

We included all consecutive patients undergoing LVAD implantation between January 1, 2010, and January 1, 2019, in a single institution. Infection-related data were retrospectively collected by review of patient's medical files. LVAD-associated infections were classified into three categories: percutaneous driveline infections, pocket infections and pump and/or cannula infections.

Results

We enrolled 72 patients. Twenty-one (29.2%) patients presented a total of 32 LVAD-associated infections. Eight (38.1%) patients had more than one infection. Five (62.5%) pocket infections and one (50.0%) pump and/or cannula infection were preceded by a driveline infection. The median delay between the operation and LVAD-associated infection was 6.5 (1.4-12.4) months. The probability of having a LVAD-associated infection at one year after receiving an implant was 26.6% (95% CI: 17.5-40.5%). Percutaneous driveline infections represented 68.7% of all LVAD-associated infections. Staphylococcus aureus and coagulase-negative staphylococci were the predominant bacteria in LVAD-associated infections (53.1% and 15.6%, respectively). Hospital length of stay (sdHR =1.22 per 10 days; P=0.001) and postoperative hemodialysis (sdHR =0.17; P=0.004) were statistically associated with infection. Colonization with multidrug-resistant bacteria was more frequent in patients with LVAD-associated infections than in others patients (42.9% vs. 15.7%; P=0.013).

Conclusions

LVAD-associated infections remain an important complication and are mostly represented by percutaneous driveline infections. Gram-positive cocci are the main pathogens isolated in microbiological samples. Patients with LVAD-associated infections are more frequently colonized with multidrug-resistant bacteria.

Incidence of Infection and Antimicrobial Consumption in Ventricular Assist Device (VAD) Recipients at the Prince Charles Hospital (TPCH): A Retrospective Analysis

BACKGROUND

Ventricular assist devices (VADs) are frequently used as a bridge to heart transplant; however, infections are a common cause of increased morbidity and mortality. The optimal prophylactic antimicrobial regimen has not been effectively evaluated in literature.

METHODS

Forty-three (43) patients received a VAD over the 5-year study period (2012-2017) at The Prince Charles Hospital (TPCH), Brisbane Australia. Of these, 41 patients were followed from implantation until transplantation or death. Antimicrobial prophylactic regimens and individual episodes of infection were recorded. The infection profiles, including types and incidence were compared to published literature using definitions from the International Society for Heart and Lung Transplantation (ISHLT) guidelines for consistency.

RESULTS

Median duration of VAD insertion was 79 days (IQR: 36-167). Patients received aztreonam, fluconazole and vancomycin (median duration 8 days). Twenty-two (22) (53.6%) patients experienced a VAD-specific and/or a VAD-related infective episode. Incidence of infection in the study cohort was 0.60 infections per 100 patient days. Thirteen (13) patients (31.7%) experienced 16 VAD-specific infections which were all driveline infections. Thirteen (13) patients (31.7%) experienced 14 VAD-related infections. The predominant VAD-related infection type was bacteraemia (36%). Predominant bacterial profiles of VAD-specific as well as VAD related infections were gram positive. Only three episodes had a gram negative as a causative pathogen which occurred much later post VAD insertion. Median time till VAD-specific or VAD-related infection was 46 and 15 days respectively. Obesity was significantly associated with increased risk of infection (HR: 3.2; 95% CI: 1.3-7.4).

CONCLUSIONS

Infection is a common complication of VAD implantation. In our study population gram positive bacteria were the predominant causative pathogen. Based on the micro-organism profile there may be scope for a narrowing of the antibiotic regimen. A larger, multicentre study would be able to accurately guide a change. The information gathered in our study offers a strong foundation for such a multicentre study.

Nasal colonization with Staphylococcus aureus is a risk factor for ventricular assist device infection in the first year after implantation: A prospective, single-centre, cohort study

OBJECTIVES

To assess, whether S. aureus nasal colonization is a risk factor for infections in patients with durable ventricular assist device (VAD).

METHODS

Prospective, single-centre, cohort study (i) ascertaining S. aureus nasal colonization status of patients admitted for VAD-implantation and detecting time to first episode of VAD-specific or -related infection according to International Society for Heart and Lung Transplantation criteria during follow-up and (ii) comparing whole genomes of S. aureus from baseline colonization and later infection.

RESULTS

Among 49 patients (17 colonized, 32 non-colonized), S. aureus VAD-infections occurred with long latency after implantation (inter quartile range 76-217 days), but occurred earlier (log-rank test P = 0.006) and were more common (9/17, 52.9% vs. 4/32, 12.5%, P = 0.005; incidence rates 2.81 vs. 0.61/1000 patient days; incidence rate ratio 4.65, 95% confidence interval 1.30-20.65, P = 0.009) among those nasally colonized with S. aureus before implantation. We found a similar but less pronounced effect of colonization status when analysing its effect on all types of VAD-infections (10/17, 58.8% vs. 7/32, 21.9%, P = 0.01). These findings remained robust when adjusting for potential confounders and restricting the analysis to 'proven infections'. 75% (6/8) of paired S. aureus samples from colonization and VAD-infection showed concordant whole genomes.

CONCLUSIONS

In patients with durable VAD, S. aureus nasal colonization is a source of endogenous infection, often occurring months after device-implantation and affecting mostly the driveline. Hygiene measures interrupting the endogenous route of transmission in VAD-patients colonized with S. aureus long-term may about half the burden of infections and require clinical scrutiny.

2019 EACTS Expert Consensus on long-term mechanical circulatory support

Long-term mechanical circulatory support (LT-MCS) is an important treatment modality for patients with severe heart failure. Different devices are available, and many-sometimes contradictory-observations regarding patient selection, surgical techniques, perioperative management and follow-up have been published. With the growing expertise in this field, the European Association for Cardio-Thoracic Surgery (EACTS) recognized a need for a structured multidisciplinary consensus about the approach to patients with LT-MCS. However, the evidence published so far is insufficient to allow for generation of meaningful guidelines complying with EACTS requirements. Instead, the EACTS presents an expert opinion in the LT-MCS field. This expert opinion addresses patient evaluation and preoperative optimization as well as management of cardiac and non-cardiac comorbidities. Further, extensive operative implantation techniques are summarized and evaluated by leading experts, depending on both patient characteristics and device selection. The faculty recognized that postoperative management is multidisciplinary and includes aspects of intensive care unit stay, rehabilitation, ambulatory care, myocardial recovery and end-of-life care and mirrored this fact in this paper. Additionally, the opinions of experts on diagnosis and management of adverse events including bleeding, cerebrovascular accidents and device malfunction are presented. In this expert consensus, the evidence for the complete management from patient selection to end-of-life care is carefully reviewed with the aim of guiding clinicians in optimizing management of patients considered for or supported by an LT-MCS device.

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.

PET/Computed Tomography Evaluation of Infection of the Heart

The 2015 European Society of Cardiology guidelines for the management of infective endocarditis included 18F-fluorodeoxyglucose (18F-FDG) PET/computed tomography (CT) in the diagnostic work-up of prosthetic valve endocarditis. This article examines the literature from the last 3 years to highlight the additional role 18F-FDG-PET/CT can contribute to an accurate diagnosis of cardiac infections and associated infectious complications. The challenges and pitfalls associated with 18F-FDG-PET/CT in such clinical settings must be recognized and these are discussed along with the suggested protocols that may be incorporated in an attempt to address these issues.

High-Quality Draft Genome Sequence of Pseudomonas aeruginosa 268 Isolated from a Patient with a Left Ventricular Assist Device

Pseudomonas aeruginosa is known to cause persistent bloodstream infections associated with left ventricular assist devices (LVAD). Here, we present the high-quality draft genome assembly for a clinical isolate, P. aeruginosa 268.

Pseudomonas aeruginosa is known to cause persistent bloodstream infections associated with left ventricular assist devices (LVAD). Here, we present the high-quality draft genome assembly for a clinical isolate, P. aeruginosa 268. The genome sequence is available in GenBank under accession number CP032761.

F-fluorodeoxyglucose-positive emission tomography/CT imaging for left ventricular assist device-associated infections in children

Left ventricular assist device implantation is an important therapeutic option for children with end-stage heart failure. However, device-related complications such as infection may occur while the patient is supported. Device-associated infection can be life-threatening, and early detection is critical. F-fluorodeoxyglucose positron emission tomography and CT is a highly sensitive imaging modality for the detection of an inflammatory response and is useful to evaluate the response to antibiotic therapy. We present two case reports of a left ventricular assist device-associated infection detected by F-fluorodeoxyglucose positron emission tomography and CT in children.

Ventricular Assist Devices: Current State and Challenges

Cardiovascular disease (CVD), as the most prevalent human disease, incorporates a broad spectrum of cardiovascular system malfunctions/disorders. While cardiac transplantation is widely acknowledged as the optional treatment for patients suffering from end-stage heart failure (HF), due to its related drawbacks, such as the unavailability of heart donors, alternative treatments, i.e., implanting a ventricular assist device (VAD), it has been extensively utilized in recent years to recover heart function. However, this solution is thought problematic as it fails to satisfactorily provide lifelong support for patients at the end-stage of HF, nor does is solve the problem of their extensive postsurgery complications. In recent years, the huge technological advancements have enabled the manufacturing of a wide variety of reliable VAD devices, which provides a promising avenue for utilizing VAD implantation as the destination therapy (DT) in the future. Along with typical VAD systems, other innovative mechanical devices for cardiac support, as well as cell therapy and bioartificial cardiac tissue, have resulted in researchers proposing a new HF therapy. This paper aims to concisely review the current state of VAD technology, summarize recent advancements, discuss related complications, and argue for the development of the envisioned alternatives of HF therapy.

Correlation between driveline features and driveline infection in left ventricular assist device selection

Although the survival rate for left ventricular assist device (LVAD) therapy has improved, device-related complications are an unpredictable threat to the patient's quality of life. We focused on driveline infection, and aimed to determine whether specific features of drivelines affect the frequency of infection. We enrolled patients who underwent LVAD implantation and were followed-up at our institute between 2007 and 2015. We counted the occurrences of driveline infection requiring any antibiotic therapy over a 2-year study period. Furthermore, we experimentally measured and compared the outer diameters and stiffness of three devices. Of all, 72 patients received an LVAD during the enrollment period. LVADs were HeartMate II (n = 32), EVAHEART (n = 22), and DuraHeart (n = 18). The outer diameters and stiffness were measured in five of each device. HeartMate II group had the highest driveline infection-free rate among all three devices during the study period (p = 0.042). The driveline of the HeartMate II LVAD had a significantly smaller outer diameter and lower stiffness than that of the other two devices (p < 0.05 for both). In conclusion, device-specific driveline features may affect the development of driveline infection during LVAD therapy.

Left ventricular assist device driveline infections: recent advances and future goals

Left ventricular assist devices (LVADs) have revolutionized the treatment of advanced heart failure, but infection remains a substantial risk. LVAD driveline infections (DLIs) are the most common type of LVAD-associated infection (LVADI). In the past several years we have expanded our understanding of DLI epidemiology, standardized the definition of LVADIs, improved infection rates through changes in implantation techniques, and investigated potential new modalities for DLI diagnosis. However, significant challenges remain for optimizing DLI prevention and treatment. These challenges include standardizing and improving both empiric and targeted antimicrobial therapy, expanding our understanding of effective driveline exit site dressings and topical therapies, and defining the patient population that benefits from device exchange and transplant. Additionally, in an era of expanding antibiotic resistance we need to continue investigating novel, non-antibiotic therapies for prevention and treatment of DLIs.

The Importance of the Management of Infectious Complications for Patients with Left Ventricular Assist Device

A left ventricular assist device (LVAD) therapy is the viable option for patients with advanced heart failure as a bridge to transplantation, bridge to recovery, or destination therapy. Although application of LVAD support has become a standard option, serious complications or adverse events related with LVAD remain a concern. LVAD-related infection including driveline infection (DLI) and bloodstream infection (BSI) is one of the serious clinical matters for LVAD patients, and especially BSI leads to the high incidence of mortality. The LVAD-related infections negatively impact patient’s quality of life. Therefore, control of infection is one of the primary goals of management in LVAD patients. Several efforts including early and appropriate intervention including antibiotics and wound care may contribute to avert the progress into BSI from localized DLI. Particularly, there are clinical secrets in how to use antibiotics and how to treat wound care in LVAD patients. The rational way of thinking for wound care will be introduced in this review.