Association of preoperative infections, nasal Staphylococcus aureus colonization and gut microbiota with left ventricular assist device outcomes

Abstract

Aims Infections are common following left ventricular assist device (LVAD) implantation and predict adverse events. Infections are frequent prior to LVAD implantation although their impact on postoperative outcomes remains unknown. Gut and nasal microbial imbalance may predispose to mucosal colonization with pathogens. Herein, we investigated the predictive role of pre‐LVAD infections, and explored the association of nasal Staphylococcus aureus (SA) colonization and gut microbiota, on postoperative outcomes. Methods and results Overall, 254 LVAD patients were retrospectively categorized based on pre‐LVAD infection status: Group 1, bacterial/fungal bloodstream infection (BSI); Group 2, other bacterial/fungal; Group 3, viral; and Group 4, no infection. In a subset of patients, nasal SA colonization (n = 140) and pre‐LVAD stool (n = 25) were analysed using 16S rRNA sequencing. A total of 75 (29%) patients had a pre‐LVAD infection [Group 1: 22 (29%); Group 2: 41 (55%); Group 3: 12 (16%)]. Pre‐LVAD BSIs were independent predictors of 1‐year postoperative mortality and infections [Group 1 vs. 4: hazard ratio (HR) 2.70, P = 0.036 vs. HR 1.8, P = 0.046]. In an unadjusted analysis, pre‐LVAD infections other than BSIs, INTERMACS profile ≤2, higher serum creatinine, lower serum albumin and nasal SA colonization were also significantly associated with postoperative infections. Patients with early post‐LVAD infections exhibited decreased microbial diversity (P < 0.05). Conclusions Pre‐LVAD infections are common. BSIs independently predict postoperative mortality and infections. Additional studies are needed to confirm our findings that pre‐LVAD SA nasal colonization and gut microbial composition can help stratify patients' risk for infectious complications after LVAD implantation.

Existing evidence supports clinical trials on interventions preventing ventricular assist device infection in patients colonized with Staphylococcus aureus. Letter regarding the article ‘Association of preoperative infections, nasal Staphylococcus aureus colonization and gut microbiota with left ventricular assist device outcomes’

“…. Therefore, we believe that our earlier work 2 in conjunction with the observations by Yuzefpolskaya et al1 form a sound evidence basis for clinical trials on infection prevention in S. aureus-colonized patients that undergo LVAD therapy. Hence, we strongly oppose the call for more confirmatory research on the association of S. aureus colonization and LVAD infection by Yuzefpolskaya et al1 and ask the research community, based on the existing evidence, to refrain from any further delay in clinical development or adaptation of life-saving decolonization protocols that have proven useful in similar settings 3.…”

“…We read with great interest the work of Yuzefpolskaya et al 1 published in this Journal. However, we would like to bring to the readers' attention that the discussion and conclusions drawn by the authors do not include the results of one prospective cohort study which demonstrated that Staphylococcus aureus nasal colonization prior to left ventricular assist device (LVAD) implantation is associated with about 5-fold increased risk of S. aureus-associated device infection during the first year of follow-up (incidence rate ratio 4.65, 95% confidence interval 1.30-20.65, P = 0.009).…”

“…2 We feel that these findings, which we had published 6 months earlier, 2 are of utmost relevance when contextualizing the results by Yuzefpolskaya et al, since they put their findings into a rather 'confirmatory' than the originally presented 'hypothesis generating' perspective. 1 More specifically, based on the combined evidence of both studies,…”

Heart failure: an update from the last years and a look at the near future

“…333 Infections are common following LVAD implantation and predict adverse events. 334 The ARIES HM3 trial is an international, RCT to test the hypothesis that aspirin may be removed safely from the antithrombotic regimen with the HM3 LVAD to reduce bleeding risk. 335 Palliative care Quality of life is clinically relevant in patients with HF and has become a major endpoint for HF studies.…”

Reply to ‘Existing evidence supports clinical trials on interventions preventing ventricular assist device infection in patients colonized with Staphylococcus aureus’

“…We appreciate the important comments by Drs Nurjadi, Ruhparwar and Zanger to our work. 1 Firstly, we apologize for not quoting their recent publication, 2 which was clearly unintentional. We also agree and are pleased to see that our data are confirmatory of their findings that show that Staphylococcus aureus nasal colonization is a risk factor for post-left ventricular assist device (LVAD) infections.…”