Baddour, Larry M.

Background: In 2007, the American Heart Association (AHA) infective endocarditis (IE) prevention guidelines recommended that antibiotic prophylaxis before invasive dental procedures for the “moderate risk” (MR) group, which represented the bulk of patients who were to receive prophylaxis before 2007, be eliminated. This decision was met with much concern among some healthcare providers and that concern persists today. We therefore evaluated dental office records in Olmsted County (OC), Minnesota to determine whether patients included in the MR group continue to receive antibiotic prophylaxis despite the 2007 AHA recommendations. Methods: Eligible patients include all adult (≥18 years) residents of OC, classified as having MR cardiac condition for IE (i.e. mitral valve prolapse [MVP], bicuspid aortic valve [BAV], hypertrophic obstructive cardiomyopathy [HOCM], acquired valvular dysfunction [AVD]), with at least one dental visit between January 1, 2005 and June 1, 2015. Eight dental offices located within OC were sampled to identify both dental procedures and whether antibiotic prophylaxis was administered according to AHA guidelines. Results: We identified 334 MR patients. Approximately 62% of MR patients received antibiotic prophylaxis prior to the change in AHA guidelines in 2007. There was a decrease to 7% post-2007 AHA guidelines (P<.001). The magnitude of decline was greater among visits for dental cleanings (from 63% to 6%), as compared to other invasive procedures (57% to 11%; P=0.003) (Figure 1). AVD was the most common cardiac condition (85%), followed by MVP (8%), and BAV (4%). Conclusion: Following publication of the 2007 AHA IE prevention guidelines, there was a rapid, 9-fold decrease in antibiotic prophylaxis in patients with MR cardiac conditions who underwent invasive dental procedures in OC. These data are also critical as we attempt to evaluate the impact, if any, of this practice on the incidence of IE due to viridans group streptococci.

AbstractBackgroundOptimal timing of cardiovascular implantable electronic device (CIED) re‐implantation following device removal due to infection is undefined. Multinational guidelines reflect this and include no specific recommendation for this timing, while others have recommended waiting at least 14 days in cases of CIED related infective endocarditis (CIED‐IE). The current work seeks to clarify this issue.MethodsWe retrospectively reviewed institutional data at Mayo Clinic, Minnesota of patients aged ≥ 18 years who developed CIED‐IE from January 1, 1991 to February 1, 2016. CIED‐IE was defined as echocardiogram reported device lead or valvular vegetation. Regression analyses were used to relate the risk of clinical outcomes to the interval between CIED removal and re‐implantation and the location of vegetations.ResultsA total of 109 patients met study inclusion criteria. A majority (68.8%) of patients were men and the median age was 68.0 years. Transoesophageal echocardiogram (TEE) was performed in 95.4% of patients, with valve vegetations detected in 33.9% (n = 37). Survival analysis comparing patients in whom device re‐implantation was < 14 days vs. ≥14 days, and further categorized by those with and without valve vegetation, showed a significant difference (P = 0.028); patients with valve vegetation and reimplantation interval < 14 days had the lowest (58.7%) 12‐month survival. When adjusted for valve vegetation, longer time interval for reimplantation trended toward increased hospital length of stay (P = 0.079).ConclusionOur findings suggest that the recommended 14‐day delay between CIED extraction and re‐implantation in CIED‐IE patients is associated with a survival benefit, but longer length of hospital stay following re‐implantation.

Introduction: Cardiovascular implantable electronic devices (CIED) infections are frequently complicated with bloodstream infection (BSI). Complete device removal and prolonged antimicrobial therapy is essential for cure. The frequency of persistent BSI after source control (device extraction) is not well described. This study aims to assess the utility of repeat blood cultures (BC) after device extraction as recommended by the American Heart Association (AHA) guidelines. Methods: We selected patients who presented with BSI in the setting of CIED infection and underwent device removal at Mayo Clinic Rochester between 2012 and 2017. Cases where BC were not drawn prior to extraction, or repeated within 72 hours of device extraction, or met criteria for contamination were excluded. Results: Of 656 patients who underwent CIED extraction for device infection, 190 with post-extraction BC met study criteria. Among the final study cohort (Table 1), 159 patients had negative BC, while 31 had positive BC following CIED extraction. Pre-extraction, the most common causative organism was Staphylococcus aureus (91/190, 48%) (Figure 1a). Post-extraction, 22 of the 31 (71%) cases of persistent BSI were due to S. aureus (Fig 1b). The median duration of BSI was not significantly different between negative and positive BC groups (3 versus 4 days, p=0.92). Conclusions: Majority of patients had resolution of BSI after CIED extraction. S. aureus was the most common cause of persistent BSI post-extraction. Our findings support the AHA guidelines of repeating BC after device extraction, especially for S aureus .

Introduction: Practice guidelines recommend use of subcutaneous implantable cardioverter-defibrillators (ICD) in patients (pts) at risk of sudden cardiac death and high risk for infection. This has prompted a need to better identify pts at high risk of infection to assist in de novo device selection. The objective of this study is to estimate infection incidence in de novo transvenous (TV) ICD implants and assess risk factors associated with infection in a large Medicare population. Methods: A retrospective cohort study was conducted using 100% Medicare administrative and claims data to identify pts who underwent de novo TV-ICD implantation between 7/2016 and 1/2018. Device-related infection within 2 years of implantation was identified using ICD-10 diagnosis and procedure codes. Baseline pt factors associated with infection were identified by univariable logistic regression analysis of all variables of interest, including factors in Charlson and Elixhauser comorbidity indices, followed by stepwise selection criteria with a p≤0.25 for inclusion in a multivariable model and a backwards, stepwise elimination process with p≤0.1 to remain in the model. A time-to-event analysis was also conducted. Results: Among 26,742 pts with de novo TV-ICD, 519 (1.9%) had a device-related infection over 2 years. The mean pt age with and without infection was 68 and 71 years, respectively. While more than half (54%) of infections occurred within 90 days post implant, infections continued to be diagnosed with 16% of infections occurring between years 1 and 2. Multivariable analysis revealed several significant predictors of infection (Figure) including age <70 years, end stage renal disease with chronic dialysis and diabetes with complications. Conclusion: The rate of de novo TV-ICD infection in a large real-world Medicare population is clinically significant. The factors associated with increased infection risk identified here can be used to help determine device selection.

Abstract Background A population-based study of infective endocarditis (IE) in Olmsted County, Minnesota, provides a unique opportunity to define temporal and seasonal variations in IE incidence over an extended time period. Methods This was a population-based review of all adults (≥18 years) residing in Olmsted County, Minnesota, with definite or possible IE using the Rochester Epidemiology Project from January 1, 1970, through December 31, 2018. Poisson regression was used to characterize the trends in IE incidence; models were fitted with age, sex, calendar time, and season, allowing for nonlinearity and nonadditivity of their effects. Results Overall, 269 cases of IE were identified over a 49-year study period. The median age of IE cases was 67.2 years, and 33.8% were female. The overall age- and sex-adjusted incidence of IE was 7.9 cases per 100 000 person-years (95% CI, 7.0–8.9), with corresponding rates of 2.4, 2.4, 0.9, and 0.7 per 100 000 person-years for Staphylococcus aureus, viridans group streptococci (VGS), Enterococcus species, and coagulase-negative staphylococci IE, respectively. Temporal trends varied by age, sex, and season, but on average IE incidence increased over time (P = .021). Enterococcal IE increased the most (P = .018), while S. aureus IE appeared to increase but mostly in the winter months (P = .018). Between 1996 and 2018, the incidence of VGS IE was relatively stable, with no statistically significant difference in the trends before and after the 2007 AHA IE prevention guidelines. Conclusions Overall, IE incidence, and specifically enterococcal IE, increased over time, while S. aureus IE was seasonally dependent. There was no statistically significant difference in VGS IE incidence in the periods before and after publication of the 2007 AHA IE prevention guidelines.

Abstract Background Bloodstream infections (BSIs) confer an increased risk of infective endocarditis (IE) in patients with a prosthetic cardiac valve. This relationship is less well established in patients undergoing valve repair. We conducted a retrospective population-based study to determine the incidence of BSIs following valve repair and identify risk factors associated with the development of IE. Methods The Rochester Epidemiology Project (REP) data linkage system was used to identify all persons who underwent valve repair in a 7-county region in Southeastern Minnesota between January 1, 2010 and December 31, 2018. Medical records were screened for the development of a BSI from time of procedure until May 15, 2020. Patients were classified as having BSI only, BSI with IE at outset, or BSI with subsequent development of new IE. IE at outset was defined as cases where IE was diagnosed at the time of initial positive blood culture. Results A total of 387 patients underwent valve repair surgery. A total of 31 (8%) patients subsequently developed a BSI, 4% within one year of surgery. Seventeen patients underwent mitral repair with annuloplasty, 9 underwent tricuspid annuloplasty, and 5 had concurrent repairs. Median time to the development of BSI was 338 days. Of the 31 patients with BSI, 4 (13%) had BSI with IE at outset. No patients developed IE subsequent to BSI, Enterococcus spp. was responsible for 3 cases of IE, and MSSA for 1. All cases occurred within one year of surgery. Given the low incidence, statistical analysis of associated risk factors for IE was not feasible. All patients with BSI and IE at outset, however, died by the end of the study period, versus 11/27 in the BSI only group. Conclusion Incidence of BSIs was higher in patients undergoing cardiac valve repair than in the general population. The incidence of IE with a BSI was 13%, which is lower than what has been previously published. It is notable that all cases of IE occurred within one year of surgery. Recognizing that endothelialization of device surfaces occurs, it is tempting to speculate that the risk of IE may be time dependent and may decline over time. Subsequent investigation of this theory is underway. Disclosures Larry M. Baddour, MD, Boston Scientific (Consultant)

Abstract Background Transcatheter aortic valve replacement (TAVR) was initially approved as an alternative to surgery for patients at high surgical risk. However, it is now being considered for patients with intermediate and low surgical risk. This will result in the expansion of patient pool for TAVR; hence it is of interest to ascertain risk of blood stream infection (BSI) and infective endocarditis (IE) following TAVR. We aim to study the incidence, epidemiology and risk factors associated with IE in patients who underwent TAVR and subsequently developed a BSI. Methods A population-based study was conducted in 7 counties in southeastern Minnesota using the expanded Rochester Epidemiology Project (E-REP) for all adult (≥18 years) patients who underwent TAVR from January 1st, 2010 to December 31st, 2018. Transcatheter procedures that included replacement of either the aortic or mitral valve were included. Medical records were screened for development of BSI from time of TAVR until May 15th, 2020. Patients were classified as having BSI only, BSI with IE at outset, or BSI with subsequent development of new IE. ‘Early’ IE was defined as that occurring &lt; 12 months following TAVR, with subsequent cases defined as ‘late’ IE. Results A total of 247 patients underwent TAVR during the study period. There were 24 patients with of BSI and 10 (42%) developed IE with an annual incidence of 5 per 1000 persons-years. Median age for patients who developed IE was 85.4 years. Male gender was affected predominantly (70%). Six developed IE at outset of BSI, while four developed IE subsequent to IE. The median time to development of IE was 791 days following TAVR. There was an equal number of early and late IE cases (n=5). The most common pathogen causing IE was viridians group streptococci (n=4) followed by enterococci and coagulase-negative staphylococci with 2 patients each. Mean Charlson comorbidity index was 6.6. Two patients with IE died before resolution of infection (20%). Conclusion The incidence of BSI and subsequent IE in patients with TAVR was low in our population. Due to the small number of BSI and IE cases, statistical analysis was not feasible. An analysis of all cases seen at Mayo Clinic is planned since the number of cases would be much higher to investigate potential risk factors associated with BSI and IE. Disclosures Larry M. Baddour, MD, Boston Scientific (Consultant) M. Rizwan Sohail, MD, Aziyo Biologics (Consultant)Medtronic Inc (Consultant, Research Grant or Support)

AbstractBackgroundAscertaining involvement of left ventricular assist device (LVAD) in a patient presenting with bloodstream infection (BSI) can be challenging, frequently leading to use of chronic antimicrobial suppressive (CAS) therapy. We aimed to assess the efficacy of CAS therapy to prevent relapse of BSI from LVAD and non-LVAD sources.MethodsWe retrospectively screened adults receiving LVAD support from 2010 through 2018, to identify cases of BSI. Bloodstream infection events were classified into LVAD-related, LVAD-associated, and non-LVAD BSIs.ResultsA total of 121 episodes of BSI were identified in 80 patients. Of these, 35 cases in the LVAD-related, 14 in the LVAD-associated, and 46 in the non-LVAD BSI groups completed the recommended initial course of therapy and were evaluated for CAS therapy. Chronic antimicrobial suppressive therapy was prescribed in most of the LVAD-related BSI cases (32 of 35, 91.4%) and 12 (37.5%) experienced relapse. Chronic antimicrobial suppressive therapy was not prescribed in a majority of non-LVAD BSI cases (33, 58.9%), and most (31, 93.9%) did not experience relapse. Chronic antimicrobial suppressive therapy was prescribed in 9 of 14 (64.2%) cases of LVAD-associated BSI and none experienced relapse. Of the 5 cases in this group that were managed without CAS, 2 had relapse.ConclusionsPatients presenting with LVAD-related BSI are at high risk of relapse. Consequently, CAS therapy may be a reasonable approach in the management of these cases. In contrast, routine use of CAS therapy may be unnecessary for non-LVAD BSIs.

Background: Left atrial appendage occlusion with the Watchman device is an alternative strategy for stroke risk reduction in patients with non-valvular atrial fibrillation. There are rare case reports of Watchman associated infection. Currently, there is no formal study that evaluated the incidence and outcomes of Watchman-related infections. Methods: All patients who underwent Watchman implantation over a 14 year study period (July 2004 through December 2018) comprised our cohort. Baseline characteristics, procedural data, and post-implantation events were identified. Primary study outcomes included Watchman related infection, other cardiovascular device related infection, bacteremia, and mortality. Results: A total of 181 patients with an average age of 75, and a median CHA2DS2-VASc Score of 4 (interquartile range 2) and a median HAS-BLED Score of 3 (interquartile range 1), were included for analysis. A total of 534.7 patient years of follow up was accrued with an average of 2.9 years per patient. The most common indications for implantation included gastrointestinal bleeding (56 patients; 30.9%) and intracerebral bleeding (51 patients; 28.2%). During follow up, 38 patients (21%) died. Six developed evidence of bacteremia. Only one developed an implantable cardioverter defibrillator (ICD) infection that required complete system extraction. None of the cohort developed Watchman-related device infection during the study period. Conclusion: In a single center study spanning a 14 year period, we report no Watchman-related devices infections. This is despite the presence of patients with bacteremia, as well as an ICD infection requiring extraction. These data suggest that Watchman devices are extremely unlikely to become infected.

The increasing incidence of infective endocarditis in England is real, and education is critical to ensure swift diagnosis and best clinical outcomes. Factors responsible remain speculative, but multiple explanations are likely.