Lahr, Brian D.

AbstractBackgroundObesity has been associated with an increased risk of vascular complication during percutaneous coronary intervention, but there are no data on the risk of vascular complication during percutaneous transfemoral transcatheter aortic valve insertion (TAVI).ObjectivesWe hypothesized there would be a similar increased risk associated with TAVI.MethodsWe reviewed the records of 1176 patients who received percutaneous transfemoral transcatheter aortic valve insertion from September 2015 to September 2020. All patients received 1) preoperative computed tomoraphy angiography assessment of the abdomen and pelvis to delineate iliofemoral artery anatomy, 2) ultrasound‐guided percutaneous femoral arterial access, and 3) pre‐closure of the delivery sheath femoral access site. Vascular complication was recorded based on definitions set forth by Valve Academic Research Consortium 3.ResultsThe median age of patients was 81 years, and 60% were men. The median body mass index (BMI) was 29 kg/m2 (range, 11–67), and 91 (8%) patients had a value ≥40 kg/m2 (i.e., morbid obesity). Delivery sheath size was 14‐French in 859 (73%) patients, 16‐French in 311 (26%), and 18‐French in 6 (1%). Vascular complication occurred in 53 (5%) patients, including 39 (7%) among the first half of procedures and 14 (2%) among the second half (p < 0.001). When stratified by obesity status (BMI < or ≥30 kg/m2, p < 0.001), the complication rate was 4% in nonobese patients and 5% in obese patients. Multivariable analysis showed no overall association between risk of vascular complication and BMI categories (p = 0.583)BMI continuous values (p = 0.529), or sheath size (p = 0.217).ConclusionsObesity is not associated with a vascular complication during percutaneous transfemoral transcatheter aortic valve insertion. The operation should not be denied in obese patients.

Abstract OBJECTIVES Delayed sternal closure (DSC) after cardiac surgery is a temporizing measure to address coagulopathy or haemodynamic instability after cardiac surgery. We sought to study: (i) indications and temporal trends for DSC, (ii) factors associated with time to chest closure and (iii) its impact on short-term and long-term outcomes. METHODS From January 2007 to December 2017, 494 patients (median age 67 years, 66% males) required DSC after cardiac surgery. Medical records were reviewed for indications, risk factors, time to DSC and outcomes. Multivariable Cox regression via landmark analysis of 486 5-day survivors was used to investigate the impact of time to chest closure on early and late survival. RESULTS Coagulopathy and haemodynamic instability were the most common indications. Median time to chest closure was 2 days. Pre-/intraoperative extracorporeal membranous oxygenation, severe right ventricular dysfunction and diabetes mellitus were associated with longer time to chest closure. Longer time to closure was associated with increased risk of operative complications and operative mortality, but did not have a statistically significant association with late mortality. Increasing age, pulmonary hypertension and a greater number of prior sternotomies were also found to be associated with overall mortality. CONCLUSIONS While longer time to chest closure was associated with increased rates of operative complications and operative mortality, it did not reveal a statistically significant association with long-term survival.

Abstract Background Staphylococcus aureus has high mortality rates, which is influenced by several factors related to the host-pathogen interaction. The current study aims to provide a contemporary evaluation of predictors of 6-month mortality rate in a population-based cohort of incident Staphylococcus aureus bacteremia (SAB) cases. Methods Retrospective population-based study of 541 adult residents of Olmsted County, MN with monomicrobial SAB from January 1, 2006 through December 31, 2020. The study’s primary outcome was 6-month mortality rate, and a survival analysis was prepared by the Kaplan-Meier method. Multivariable Cox regression was used to investigate risk factors associated with 6-month mortality. Results The median (IQR) age of 541 patients with SAB was 66.8 (54.4-78.5) years and 39.6% were female. The median Charlson Comorbidity Index (CCI) was 2 (1-4). SAB cases were healthcare-associated in 49.2% and 56.2% were methicillin-susceptible. Twenty percent of SAB cases had an unknown infection source and 38.3% had complicated bacteremia. There were 7 relapses within the first 12 weeks of follow-up, corresponding to a cumulative incidence rate of 1.3%. There were no re-infections through the remainder of the 6-month follow-up, although there were 2 recurrences after 7 months. Eighty-nine (16.5%) patients died within 1 month of SAB diagnosis and 144 (26.7%) patients died during the 6-month follow-up period. In a multivariable analysis, older age, elevated CCI, unknown source of SAB, and intensive care unit (ICU) admission were significant predictors of an increased 6-month mortality rate. In contrast, presence of diabetes mellitus was significantly associated with a decreased 6-month mortality rate; also, undergoing infectious diseases consultation was associated with reduced mortality in the first 2 weeks, but not for the remainder of the 6-month follow-up period. Conclusion To our knowledge, the current investigation represents the only contemporary population-based study determining significant predictors of mortality in SAB patients, namely, older age, higher CCI, unknown source of SAB, and ICU admission. This study also described one of the lowest 30-day mortality rates reported over the past 2 decades. Figure 1.Survival and reinfection rates of patients with SAB over 6 months. Abbreviations: SAB, Staphylococcus aureus bacteremia. Foot notes: The overall survival curve was derived by the Kaplan-Meier estimator, while the curve for reinfection was estimated by the cumulative incidence function taking into account the competing risk of death. Disclosures Larry M. Baddour, M.D., Boston Scientific: Advisor/Consultant|Botanix Pharmaceuticals: Advisor/Consultant|Roivant Sciences: Advisor/Consultant|UpToDate, Inc.: Royalty payments - authorship duties.

Abstract Background There are anatomical, pharmacokinetic, and joint biomechanical differences between males and females. Whether these differences result in differing presentation, treatment tolerability and outcomes in periprosthetic joint infection (PJI) has not been widely evaluated. Methods We undertook a retrospective case matched study of patients with staphylococcal PJI managed with two-stage exchange arthroplasty. In order to control for differences other than sex which may influence outcome or presentation, males and females were case-matched for age, causative organism (Coagulase-negative staphylococci vs Staphylococcus aureus) and joint involved. The two matched groups were analyzed for differences in duration of symptoms, inflammatory markers, duration of hospital stay, antimicrobial side effects, post-operative complications and recurrence rate. Recurrence of infection was defined as per Musculoskeletal Infection Society criteria for PJI and included both relapse with original microorganism or with an additional organism. Results 78 pairs of males and females with staphylococcal PJI were successfully matched. There were no significant baseline differences by sex, except for greater use of chronic immunosuppression among females (16.7% vs. 4.1%; p=0.012). Clinical characteristics and outcomes of the patients are summarized in table 1. We did not detect a statistically significant between the outcomes of the two groups. Overall, 16 recurrent infections occurred during a median follow-up time of 2.9 (IQR: 1.5 - 5.3) years. The 3-year cumulative incidence of treatment failure depicted in figure 1 was 16.1% for females, compared with 8.8% for males (p=0.434). Conclusion Success rates for PJI treated with two-stage exchange arthroplasty are high consistent with previously reported literature. A larger cohort of patients may be required to detect differences in relapse rates. This study included only staphylococcal PJI and was thus unable to evaluate the differences in microbiology of PJI between males and females, which could also impact outcomes. This retrospective case-matched study did not detect any significant differences in outcomes between males and females with staphylococcal PJI who underwent two stage exchange arthroplasty. Disclosures Gina A. Suh, M.D., Adaptive Phage Therapeutics (APT): Grant/Research Support|Adaptive Phage Therapeutics (APT): Dr. Suh received grants and has an equity and royalty-bearing know-how agreement with Adaptive Phage Therapeutics but is unrelated to project Aaron J. Tande, M.D., Uptodate: Dr Tande has received an honorarium from Uptodate for medical writing unrelated to this project.

Abstract Background Bloodstream infection (BSI) following arterial aneurysm repair may signify vascular graft infection (VGI). The incidence of BSI and its implications in patients with arterial grafts have received scant attention with limited contemporary study. Therefore, the aim of the current investigation is to describe the incidence and epidemiology of BSI following arterial aneurysm repair in a population-based cohort. Methods Retrospective case-cohort study using the expanded Rochester Epidemiology Project (e-REP) to identify all arterial aneurysm repairs performed in adults (&gt;18 years) residing in eight counties in southern Minnesota between January 1, 2010 and December 31, 2020. All repairs were performed at Mayo Clinic Rochester. Electronic health records were screened for initial BSI episode following aneurysm repair and complicating VGI. Results Overall, 643 patients underwent 708 aneurysm repairs: 417 endovascular and 291 open surgical repairs. Forty-two patients developed BSI during 2,992 cumulative person-years of follow-up. The median time from repair to BSI was 3.1 [interquartile range 0.5, 6.4] years. The BSI incidence rate, in cases per 1000 person-years, was 14.0 (95% CI 10.1-19.0) overall, including 18.2 (95% CI 11.9-26.7) following open surgical repair and 10.2 (95% CI 5.8-16.6) following endovascular repair (p=0.148). Thirty-nine (92.9%) of the BSI cases were monomicrobial, with 18 (46.2%) due to Gram-positive organisms and 21 (53.8%) due to Gram-negative organisms. Of the 42 patients with BSI, 10 (23.8%) had VGI. VGI occurred in 8/18 (44.4%) monomicrobial Gram-positive BSI as compared to 2/21 (9.5%) monomicrobial Gram-negative BSI (p=0.013). The 3-year mortality rate following BSI was 52.3%. Conclusion There was no statistically significant difference in incidence rates of BSI following open surgical repair and endovascular repair. Higher rates of VGI were seen with Gram-positive BSI as compared to Gram-negative BSI. Disclosures Larry M. Baddour, M.D., Boston Scientific: Advisor/Consultant|Botanix Pharmaceuticals: Advisor/Consultant|Roivant Sciences: Advisor/Consultant|UpToDate, Inc.: Royalty payments - authorship duties.

Abstract Background Cardiovascular implantable electronic devices (CIED) infection carries significant morbidity, mortality, and financial burden. Bacteremia in patients with CIED increases risk of CIED infection. While several investigations have examined Staphylococcus aureus bacteremia and risk of CIED infection, data regarding non-S. aureus gram-positive coccal (non-SA GPC) bacteremia in patients with CIED has been both limited and dated. The current study examined the clinical characteristics of patients with CIED who developed non-SA GPC bacteremia and their proclivity of CIED infection. Methods We reviewed all patients with CIED who developed non-SA GPC bacteremia at Mayo Clinic between 2012–2019. Cases with a left ventricular assist device, non-hospitalization, and contaminated blood culture were excluded. The 2019 European Heart Rhythm Association International Consensus Document was used to define CIED infection. Results A total of 160 patients with CIED developed non-SA GPC bacteremia during the period. Ninety (56.2%) patients had CIED infection, with 60 (37.5%) classified as definite and 30 (18.8%) possible. This included 41/64 (64.1%) patients with coagulase-negative Staphylococcus (CoNS), 30/41 (73.2%) patients with Enterococcus, 13/19 (68.4%) patients with viridans group streptococci (VGS), and 6/36 (16.6%) patients with other non-SA GPC. The odds of CIED infection (with 95% CI) for CoNS, Enterococcus, and VGS bacteremia were 8.9 (3.2–24.6), 13.6 (4.5–41.6), and 10.8 (2.9–40.0) -fold higher, respectively, as compared to other non-SA GPC. Among those with infected CIED, 51 (56.7%) patients underwent complete device extraction after a median of 6 (IQR 3.5–10) days. In an unadjusted analysis of patients with CIED infection, the reduction in one-year mortality following device removal was not statistically significant (HR 0.59, 95% CI 0.26–1.33, p=0.198). Conclusion The overall prevalence of CIED infection following non-SA GPC bacteremia was higher than previously reported, particularly that due to CoNS, Enterococcus, and VGS. Further study with a larger cohort is needed to demonstrate the survival benefit from CIED extraction in patients with infected CIED due to non-SA GPC. Disclosures Larry M. Baddour, M.D., Boston Scientific: Advisor/Consultant|Botanix Pharmaceuticals: Advisor/Consultant|Roivant Sciences: Advisor/Consultant|UpToDate, Inc.: Royalty payments - authorship duties Rizwan Sohail, M.D., Aziyo Biologics: Advisor/Consultant|Boston Scientific: Advisor/Consultant|Medtronic: Advisor/Consultant|Philips: Advisor/Consultant|Philips: Honoraria Malini Madhavan, M.B.B.S., Biosense Webster: Advisor/Consultant|Biotronik Inc: Advisor/Consultant|Boston Scientific: Grant/Research Support|Convatec: Advisor/Consultant.

Objective: To provide an evaluation of incidence and six-month mortality rates of polymicrobial Staphylococcus aureus bacteremia (p-SAB) in the United States (US). Methods: A retrospective population-based study of all incident adults with monomicrobial SAB (m-SAB) and p-SAB in Olmsted County, Minnesota (MN) from 1 January 2006, through 31 December 2020, was conducted. Demographics, clinical characteristics, in-hospital outcomes, and six-month survival were compared between groups. Results: Overall, 31 incident p-SAB cases occurred during the 15-year study period, corresponding to an overall age- and sex-standardized incidence rate of 1.9/100,000 person-years (95% CI, 1.3–2.6). One-third of p-SAB cases were due to MRSA, and almost one-half (15/31) were caused by Gram-positive bacteria. As compared to the 541 cases with incident m-SAB, p-SAB patients were more likely to have a catheter-related infection (p = 0.008) and less likely to be community-acquired cases (p = 0.027). The unadjusted risk of six-month mortality was greater in the p-SAB group (14/31, 45.2%) compared to the m-SAB group (144/541, 26.6%) (HR = 1.94, 95% CI = 1.12–3.36, p = 0.018). After adjusting for relevant covariates, this difference approached significance (HR = 1.93, 95% = CI 0.96–3.87, p = 0.064). Conclusions: To our knowledge, the current investigation represents the only US population-based study evaluating p-SAB patients. We found lower incidence rates for p-SAB than previously reported, with almost one-half of the cases caused by Gram-positive bacteria. Furthermore, these patients had poor survival compared to incident m-SAB cases.

Abstract Background Image-guided biopsies in patients with suspected native vertebral osteomyelitis (NVO) are recommended to establish the microbiological diagnosis and guide antibiotic therapy. Despite recent advances, the microbiological yield of this procedure remains between 48% and 52%. A better understanding of factors associated with this low yield may lead to improved microbiological diagnosis. Methods We retrospectively identified patients with suspected NVO undergoing image-guided biopsies from January 2011 to June 2021 at our institution. Two hundred nine patients undergoing 248 percutaneous biopsies were included. Demographic data, biopsy and microbiologic techniques, clinical characteristics, and antibiotic use were collected. Multivariable logistic regression analysis was conducted to determine factors associated with microbiological yield. Results A total of 110 of 209 (52.6%) initial image-guided biopsies revealed positive microbiological results. This number increased to 121 of 209 (57.9%) when repeat image-guided biopsies were included. In multivariable analysis, aspiration of fluid was associated with a 3-fold increased odds of yielding a positive result (odds ratio [OR], 3.13; 95% confidence interval [CI], 1.39–7.04; P = .006), whereas prior antibiotic use was associated with a 3-fold decreased yield (OR, 0.32; 95% CI, .16–.65; P = .002). A univariate subgroup analysis revealed a significant association between the length of the antibiotic-free period and microbiological yield, with the lowest rates of pathogen detection at 0–3 days and higher rates as duration increased (P = .017). Conclusions Prior antibiotic use in patients with suspected NVO was associated with a decrease in the microbiological yield of image-guided biopsies. An antibiotic-free period of at least 4 days is suggested to maximize yield. Successful fluid aspiration during the procedure also increases microbiological yield.

Abstract Background Gram-negative bacteremia (GNB) as a manifestation of cardiovascular implantable electronic device (CIED) infection is uncommon. Moreover, echocardiography may be nonspecific in its ability to differentiate whether CIED lead masses are infected. We aimed to determine the rate of CIED infection in the setting of GNB. Methods All patients with CIED who were hospitalized with GNB during 2012–2019 at Mayo Clinic were investigated. The definition of CIED infection was based on criteria recommended by the 2019 European Heart Rhythm Association document. Results A total of 126 patients with CIED developed GNB. None of them had signs of pocket infection. Twenty (15.9%) patients underwent transesophageal echocardiography. Overall, 4 (3%) patients had definite CIED infection. None of them underwent CIED extraction; 3 died within 12 weeks and 1 received long-term antibiotic suppression. Ten (8%) patients had possible CIED infection; despite no CIED extraction, no patient had relapsing GNB. We observed a higher rate of CIED infection in patients with Serratia marcescens bacteremia as compared to that in patients with other GNB. Conclusions The rate of CIED infection following GNB was relatively low. However, accurate classification of CIED infection among patients presenting with GNB remains challenging, in part, due to a case definition of CIED infection that is characterized by a low pretest probability in the setting of GNB. Prospective, multicenter studies are needed to determine accurate identification of CIED infection among GNB, so that only patients with true infection undergo device removal.