Association between hemodialysis and patient characteristics, microbiological etiology, cardiac surgery, and mortality in patients with infective endocarditis: a nationwide study

Background

Hemodialysis and infective endocarditis are both associated with poor patient outcome. However, despite high mortality rates for each disease entity, little attention is given to patients on hemodialysis who develop infective endocarditis.

Purpose

To examine patient characteristics, microbiological etiology, cardiac surgery, and outcome among patients on hemodialysis with infective endocarditis compared with patients with infective endocarditis without hemodialysis treatment.

Methods

With Danish nationwide registries, we identified patients with infective endocarditis between 2010–2018 and linked them to microbiological data from a nationwide microbiological registry with complete blood culture data. We included patients in the hemodialysis group if they received hemodialysis treatment within 6 months prior to their first-time infective endocarditis admission. Patients not meeting this criteria were put in the non-hemodialysis group. We used Kaplan-Meier estimates for difference in mortality and Cox regression for adjusted analysis.

Results

We included 4,106 patients with infective endocarditis of which 265 (6.5%) patients were also in hemodialysis treatment (66.8% men). Patients on hemodialysis were younger (median age 66 years [IQR=54.2–74.9] vs. 72.3 years [IQR=62.3–80.4]) and had a higher burden of comorbidities including hypertension (68.7 vs. 56.9%), diabetes (47.2% vs. 18.8%), and ischemic heart disease (41.1% vs. 32.2%) compared to patients without hemodialysis treatment, all p-values <0.01. Cardiac surgery was less frequently performed in patients in the hemodialysis group than in the non-hemodialysis group (11.9% vs. 19.4%, respectively, p<0.001) and Staphylococcus aureus was more frequently the microbiological etiology of infective endocarditis in the hemodialysis group than in the non-hemodialysis group (57.0% vs. 25.3%, respectively, p<0.0001). No statistically significant difference for in-hospital mortality was found. Figure 1 shows difference in mortality between the two groups. 1- and 5-year mortality were significantly higher in the hemodialysis group than in the non-hemodialysis group (34.3% vs. 17.2% and 50.5% vs. 33.9%, respectively, p<0.00001) and in adjusted analysis hemodialysis was associated with higher 1- and 5-year mortality (hazard ratio of 2.41, 95% CI 1.85–3.13 and 2.50, 95% CI 2.05–3.05, respectively), as compared with patients in the non-hemodialysis group.

Conclusion

Patients on hemodialysis with infective endocarditis are younger, sicker and have Staphylococcus aureus as causing agent more than twice as often as patients with infective endocarditis without hemodialysis treatment. This patient group have a higher mortality and by 5 years, 75% of patients in our hemodialysis group were dead.

Funding Acknowledgement

Type of funding sources: None.

Risk of infective endocarditis among patients with tetralogy of fallot

Introduction

Patients with tetralogy of Fallot (ToF) are considered at high risk of infective endocarditis (IE) as a result of altered hemodynamics and multiple surgical and interventional procedures including pulmonary valve replacement (PVR). The overall survival of patients with ToF has increased in recent years. However, data on the risk of adverse outcomes including IE are sparse.

Purpose

To investigate the risk of IE in patients with ToF compared with controls from the background population.

Methods

In this nationwide observational cohort study, all patients with ToF born in 1977–2017 were identified using Danish nationwide registries and followed from date of birth until occurrence of an outcome of interest (i.e. first-time IE), death, or end of study (July 31, 2017). The comparative risk of IE among ToF patients versus age- and sex-matched controls from the background population was assessed.

Results

A total of 1,156 patients with ToF were identified and matched with 4,624 controls from the background population. Among patients with ToF, 266 (23.0%) underwent PVR during follow-up. During a median follow-up time of 20.4 years, 38 (3.3%) patients and 1 (0.03%) control were admitted with IE. The median time from date of birth to IE was 10.8 years (25th-75th percentile 2.8–20.9 years). The incidence rates of IE per 1,000 person-years were 2.2 (95% confidence interval (CI) 1.6–3.0) and 0.01 (95% CI 0.0001–0.1) among patients and controls, respectively. In multivariable Cox regression models, in which age, sex, pulmonary valve replacement, and relevant comorbidities (i.e. chronic renal failure, diabetes mellitus, presence of cardiac implantable electronic devices, other valve surgeries), were included as time-varying coefficients, the risk of IE was significantly higher among patients compared with controls (HR 171.5, 95% CI 23.2–1266.7). Moreover, PVR was associated with an increased risk of IE (HR 3.4, 95% CI 1.4–8.2).

Conclusions

Patients with ToF have a substantial risk of IE and the risk is significantly higher compared with the background population. In particular, PVR was associated with an increased risk of IE. With an increasing life-expectancy of these patients, intensified awareness, preventive measures, and surveillance of this patient group are advisable.

Figure 1. Cumulative incidence of IE

Funding Acknowledgement

Type of funding source: None

P4799Long-term thromboembolic risk in patients with postoperative atrial fibrillation after left-sided heart valve surgery

Background

New-onset postoperative atrial fibrillation (POAF) is a common complication of cardiac surgery. However, data on the long-term risk of thromboembolism in patients who develop POAF after heart valve surgery are sparse. In addition, data on stroke prophylaxis in this setting are lacking.

Objective

To assess the long-term risk of thromboembolism in patients developing new-onset POAF following isolated left-sided heart valve surgery relative to patients with nonsurgical, nonvalvular atrial fibrillation (NVAF).

Methods

Using data from the Eastern Danish Heart Surgery Database and Danish nationwide registries, we identified patients who developed POAF following isolated left-sided heart valve surgery (i.e. biologic aortic/mitral valve replacement or aortic/mitral valve repair) from 2000 through 2015. These patients were matched with patients with nonsurgical NVAF in a 1:4 ratio by age, sex, heart failure, hypertension, diabetes, a history of thromboembolism, ischemic heart disease, and year of diagnosis. Long-term risk of thromboembolism was examined by the Aalen-Johansen estimator and cause-specific Cox regression models adjusted for comorbidities, concomitant pharmacotherapy, and oral anticoagulation therapy as a time-dependent covariate.

Results

A total of 1,539 patients undergoing isolated left-sided heart valve surgery were identified. Of these, 716 (46.5%) patients developed POAF after surgery. A total of 630 patients with POAF were matched with 2,520 patients with NVAF. In the matched study population, the median age was 71 years (25th-75th percentile 66–77 years) and 59.5% were men. Oral anticoagulation therapy was initiated within 30 days post-discharge in 62.7% and 51.4% of these patients, respectively. Compared with NVAF, POAF was not associated with a significantly different 5-year absolute risk of thromboembolism (10.7% [95% confidence interval [CI], 8.0%-13.9%] versus 8.9% [95% CI, 7.6%-10.2%] in the POAF and NVAF group, respectively) (Figure). In the adjusted analysis, the long-term risk of thromboembolism was similar in patients with POAF and NVAF (hazard ratio [HR] 1.01 [95% CI, 0.71–1.44]). Anticoagulation therapy during follow-up was associated with a lower risk of thromboembolic events in patients with POAF (HR 0.45 [95% CI, 0.18–0.99]) as well as NVAF (HR 0.58 [95% CI, 0.42–0.80]) compared with no anticoagulation therapy.

Conclusions

New-onset POAF following isolated left-sided heart valve surgery was associated with a similar long-term risk of thromboembolism compared with NVAF. Future studies addressing the role of oral anticoagulation therapy in POAF after heart valve surgery are warranted to examine the efficacy and safety as well as the timing and duration of anticoagulation therapy.

P2762Recurrent infective endocarditis versus first-time infective endocarditis after heart valve surgery

Introduction

Infective endocarditis (IE) may require heart valve surgery. However, it is well-known that heart valve surgery itself and previous IE predispose to IE.

Purpose

To access the risk of recurrent IE compared with first-time IE following heart valve surgery.

Methods

Using Danish nationwide registries, patients undergoing left-sided heart valve surgery (i.e. valve replacement or repair) in the course of a first-time IE hospitalization (1996–2017) were identified and matched with patients undergoing left-sided heart valve surgery due to another cause than IE in a 1:1 ratio. Patients were stratified according to type of surgical valve intervention and affected valve. The comparative risk of IE was assessed by cumulative incidence curves and multivariable Cox regression analyses.

Results

The study population comprised 975 patients with a first-time admission for left-sided IE requiring heart valve surgery (median age, 64.3 years [interquartile range 55.7–72.1], 77.6% men) matched with 975 controls undergoing left-sided heart valve surgery due to other causes than IE. The risk of recurrent IE was significantly higher than the risk of first-time IE following heart valve surgery (5.5% and 3.1% by 10 years, hazard ratio (HR) 1.72, 95% confidence interval (CI) 1.07–2.78) (Figure 1). The risk of IE recurrence was not significantly different in patients with IE undergoing valve replacement versus valve repair (5.6% and 5.4% respectively, HR 1.76, 95% CI 0.79–3.05). Likewise, the risk of IE recurrence was not significantly different for mitral versus aortic valve patients (3.5% and 6.3%, respectively, HR 0.73, 95% CI 0.36–1.48). Yet, the risk of IE recurrence was significantly higher among IE patients with biological versus mechanical prostheses (6.4% and 4.6%, respectively, HR 2.20, 95% CI 1.13–4.31).

Figure 1: Cumulative incidences

Conclusion

Following left-sided heart valve surgery, the associated risk of recurrent IE was significantly higher than the risk of first-time IE.

Acknowledgement/Funding

None

P926Comparative safety and effectiveness of vitamin K antagonist and direct oral anticoagulants in patients with atrial fibrillation undergoing transcatheter aortic valve implantation

Background

Data on the comparative safety and effectiveness of direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) in patients with atrial fibrillation (AF) undergoing transcatheter aortic valve implantation (TAVI) are sparse.

Purpose

To examine the risk of thromboembolism, bleeding, and all-cause mortality in patients treated with DOACs versus VKAs.

Methods

Danish nationwide registries were used to identify all patients undergoing TAVI (2011–2016) with a history of AF and who were treated with oral anticoagulants. The risk of outcomes in patients treated with DOACs versus VKAs were examined by the Aalen-Johansen estimator and cause-specific Cox regression models.

Results

The study population comprised 762 patients (median age 82 [interquartile range 77–85], 52.9% men), of whom 216 (28.3%) and 546 (71.7%) patients were treated with DOACs and VKAs, respectively. The DOAC group was characterized by a higher prevalence of previous thromboembolism and a lower prevalence of chronic kidney disease compared with the VKA group. The distribution of age, sex, CHA2DS2-VASc and HAS-BLED score, and concomitant antiplatelet therapy was similar between groups. Compared with VKA, treatment with DOACs was not associated with a significantly different 3-year absolute risk of thromboembolism (9.5% [95% confidence interval [CI], 4.7%-16.2%] versus 7.7% [95% CI, 5.3%-10.8%] in the DOAC and VKA group, respectively), bleeding (5.3% [95% CI, 2.4%-10.0%] versus 6.3% [95% CI, 4.1%-9.0%]), and all-cause mortality (32.6% [95% CI, 21.9%-43.7%] versus 33.3% [95% CI, 28.3%-38.5%]). In adjusted analyses, treatment with DOACs, as compared with VKA treatment, was not associated with a significantly different risk of thromboembolism (hazard ratio [HR], 1.25 [95% CI, 0.61–2.57]), bleeding (HR, 1.22 [95% CI, 0.54–2.75]), and all-cause mortality (HR, 0.90 [95% CI, 0.60–1.35]).

Conclusions

In patients with atrial fibrillation undergoing TAVI, treatment with DOACs was not associated with a significantly different risk of thromboembolism, bleeding, and all-cause mortality compared with treatment with VKA.

Acknowledgement/Funding

None