1371. Identification of Risk Factors to Predict Gram negative bacteria in Patients with Upper Extremity Infections

Background

Gram negative bacteria (GNB) have been identified as a cause of upper extremity infections and empiric treatment directed to both gram positive and negative organisms is often recommended. Risk-based approaches to establish need for gram-negative coverage may help to minimize unnecessary drug exposure, but further information on such methods are currently lacking. The aim of this study was to identify risk factors associated with the isolation of GNB in patients with upper extremity infections.

Methods

We reviewed records of patients with upper extremity infections treated in two urban hospitals between March 2018 and July 2020. Prosthetic joint infections were excluded. Baseline demographic, clinical, surgical and microbiology data was collected. Multivariable logistic regression models were screened using Akaike Information Criterion to establish the best model and risk factors associated with isolation of a GNB.

Results

We identified 111 patients, the majority of whom were male with frequent history of IV drug use. Deep wound cultures in 30 (33.3%) individuals yielded a GNB, and 80% of these cases were polymicrobial. Among the GNB, most prevalent were Enterobacterales (10.4%), HACEK group (6.39%), and Pseudomonas spp. (4.5%) (Tables 1. and 2.). Infections were mostly limited to the soft tissue structures of the hand and the forearm, with involvements of the joint and bone being second and third most common. The final model identified the use of IV medications (OR 4.14, 95% CI 1.3 - 14.46) together with prior surgery at the site of infection within the last year (OR 5.56, 95% CI 1.06 - 30.98), and having an open wound on presentation (OR 3.03, 95% CI 1.04 - 9.47) as factors independently associated with isolation of a GNB (Table 3). AUROC of 0.702 indicates acceptable model discrimination.

Table 1: Baseline characteristics

Table 2: Bacterial isolates

Table 3: Final model

Conclusion

Our logistic regression model identified significant predictors for isolation of GNB in upper extremity infections within this population. Results of this study will assist clinicians in making a better informed decision for the need of empiric gram negative coverage aimed to support the reduction of patient exposure to unnecessary antimicrobial coverage. External validation of the model is warranted prior to application to clinical care.

Figure 1: AUROC

Disclosures

All Authors: No reported disclosures

Validation of cardiac damage classification and addition of albumin in a large cohort of patients undergoing transcatheter aortic valve replacement

AIMS

We aimed to validate a new scoring system based on extent of cardiac damage for risk stratification in patients undergoing transcatheter aortic valve replacement (TAVR) in a real-world cohort and to examine the addition of baseline albumin in risk assessment.

METHODS AND RESULTS

We investigated 2608 patients undergoing TAVR. Subjects were divided into five groups based on their echocardiography findings. Patients were further assessed by incorporating baseline albumin. Multivariable analysis demonstrated that each increase in stage was associated with significant increased risk of 1-year mortality (HR 1.37, 95%CI 1.23-1.54, p < .001). Among patients at increased stage (3-4), incorporation of baseline of albumin identified the highest risk group, such that each 1 decrement in albumin levels was associated with more than triple increase in mortality among patients at stage 3 and 4 (HR 2.77, 95% CI 1.48-5.18, p-value = .001).

CONCLUSIONS

Cardiac damage classification is validated in a real-world cohort of patients undergoing TAVR. Incorporation of low baseline albumin may further identify patients at the highest risk group.

CONDENSTED ABSTRACT

We evaluated 2608 patients undergoing transcatheter aortic valve replacement (TAVR) in order to validate a new scoring system dividing patients in to 5 stages (0-4) based on extent of cardiac damage. Patients were further assessed by incorporating baseline albumin. Multivariable analysis demonstrated that each increase in stage was associated with significant increased risk of 1-year mortality. Furthermore, among patients at increased stage (3-4), incorporation of baseline of albumin identified the highest risk group, such that each 1 decrement in albumin levels was associated with more than triple increase in mortality among patients at stage 3 and 4.

Impact of preprocedural left ventricle hypertrophy and geometrical patterns on mortality following TAVR

BACKGROUND

In contrast to surgical aortic valve replacement, left ventricle (LV) hypertrophy (LVH) had not been clearly associated with mortality following transcatheter aortic valve replacement (TAVR).

METHODS

We performed a retrospective analysis of patients enrolled in the Israeli multicenter TAVR registry for whom preprocedural LV mass index (LVMI) data were available. Patients were divided into categories according to LVMI: normal LVMI and mild, moderate, and severe LVH. Mild LVH was regarded as the reference group. Additionally, LV geometry patterns were examined (concentric and eccentric LVH, and concentric remodeling).

RESULTS

The cohort consisted of 1,559 patients, 46.5% male, with a mean age of 82.2 (±6.8) years and mean LVMI of 121 (±29) g/m². Rates of normal LVMI and mild, moderate, and severe LVH were 31% (n = 485), 21% (n = 322), 18% (n = 279), and 30% (n = 475), respectively. Three-year mortality rates for normal LVMI and mild, moderate, and severe LVH were 19.8%, 18.3%, 23.7%, and 24.4%, respectively. Compared to mild LVH, moderate LVH and severe LVH were independently associated with an increased risk for all-cause mortality (hazard ratio [HR] 1.58, 95% CI 1.15-2.18, P = .005; HR 1.46, 95% CI 1.1-1.95, P = .009; respectively). Concentric LVH was independently associated with a decreased risk for mortality compared to normal LV geometry (HR 0.75, 95% CI 0.63-0.89, P = .001). Compared to concentric LVH, eccentric LVH was independently associated with a 33% increased risk for mortality (HR 1.33, 95% CI 1.11-1.60, P = .002).

CONCLUSIONS

Mild concentric LVH confers a protective effect among patients with severe aortic stenosis undergoing TAVR. However, hypertrophy becomes maladaptive, and an increased baseline LVMI, eccentric pattern particularly, may be associated with all-cause mortality in this population.

P3857Validation of the cardiac damage classification and additional effects of albumin levels in a large cohort of patients undergoing transcatheter aortic valve replacement

Background

Risk stratification in patients undergoing transcatheter aortic valve replacement (TAVR) is limited and based on clinical judgment and surgical AVR scoring systems. Recently, extent of cardiac damage using an echocardiographic classification was purposed to assess prognosis of patients undergoing TAVR. We aimed to validate this new scoring system in a real-world cohort and to examine the addition of baseline albumin in risk assessment.

Methods

We investigated 2,608 patients undergoing TAVR. All subjects had an echocardiography test prior to TAVR. Subjects were divided into five groups based on their echocardiography findings: stage 0 – 758 (29%) patients, stage 1 – 769 (30%), stage 2 – 730 (28%), stage 3 – 320 (12%) and stage 4 (1.2%). Patients were further assessed by incorporating baseline albumin.

Results

Mean age of study population was 82±7 years. Kaplan-Meier's survival analysis showed that the cumulative probability of mortality was significantly higher among subjects with increased stage compared to the lower stages (p<0.001). Multivariable analysis demonstrated that each increase in stage was associated with significant increased risk of 1-year mortality (HR 1.37, 95% CI 1.23–1.54, p<0.001). Among patients at increased stage (3–4), incorporation of baseline of albumin identified the highest risk group, such that each 1 decrement in albumin levels was associated with more than triple increase in mortality among patients at stage 3 and 4 (HR 2.77, 95% CI 1.48–5.18, p-value=0.001)[figure]. When added to the scoring risk prediction model, albumin allowed more accurate risk stratification: continuous NRI analysis showed an overall improvement of 11% (95% CI 6%-16%) in the accuracy of classification.

KM according to stage and albumin

Conclusions

Cardiac damage classification is validated in a real-world cohort of patients undergoing TAVR. Incorporation of low baseline albumin may further identify patients at the highest risk group.

Safety outcomes of new versus old generation transcatheter aortic valves

OBJECTIVE

To compare procedural outcomes of transcatheter aortic valve implantation (TAVI) patients who were implanted with older versus newer generation valves.

BACKGROUND

The current evidence base for improved safety of the newer commercially available TAVI valves is limited.

METHODS

A retrospective analysis of the Israeli multicenter TAVI registry was performed. Patients were stratified by valve generation of four commercially available devices: Edwards Sapien (ESX) Edwards Sapien S3 (ES3), Medtronic CoreValve (MCV), and Medtronic Evolut R (MER).

RESULTS

The cohort consisted of 737 patients with new generation valves (NGVs; ES3 n = 223; MER n = 514) and 1,869 with old generation valves (OGVs; MCV n = 1,181; ESX n = 688). Device success rates were significantly higher in NGV (97.5 versus 95.4%), with less post-procedural paravalvular leak (3 versus 5.8%), and valve mal-positioning (1.2 versus 3.4%); all P-values<0.05. There were no differences in rates of permanent pacemaker implantation, stroke or acute kidney injury (AKI) of any stage between the groups, although stage ≥2 AKI was more prevalent in NGV. After adjustment to significant differences in baseline patient and procedural characteristics, device success was higher (OR 1.86, 95% confidence interval (CI) 1.09-3.18, P = 0.023) and the 1-month safety outcome was significantly lower (OR 0.72, 95% CI 0.55-0.96, P = 0.025) for NGV. Device success was driven mainly by improved rates of PVL of ES3, while the safety outcome was mainly driven by improved rates of life-threatening bleeding and valve mal-positioning of MER.

CONCLUSION

As compared to OGV, use of NGV for TAVI was associated with higher rates of device success and lower rates of adverse events.

β-Cell DNA Damage Response Promotes Islet Inflammation in Type 1 Diabetes

Type 1 diabetes (T1D) is an autoimmune disease where pancreatic β-cells are destroyed by islet-infiltrating T cells. Although a role for β-cell defects has been suspected, β-cell abnormalities are difficult to demonstrate. We show a β-cell DNA damage response (DDR), presented by activation of the 53BP1 protein and accumulation of p53, in biopsy and autopsy material from patients with recently diagnosed T1D as well as a rat model of human T1D. The β-cell DDR is more frequent in islets infiltrated by CD45⁺ immune cells, suggesting a link to islet inflammation. The β-cell toxin streptozotocin (STZ) elicits DDR in islets, both in vivo and ex vivo, and causes elevation of the proinflammatory molecules IL-1β and Cxcl10. β-Cell-specific inactivation of the master DNA repair gene ataxia telangiectasia mutated (ATM) in STZ-treated mice decreases the expression of proinflammatory cytokines in islets and attenuates the development of hyperglycemia. Together, these data suggest that β-cell DDR is an early event in T1D, possibly contributing to autoimmunity.