NatIonal Danish endocarditis stUdieS - Design and objectives of the NIDUS registry.

AIMS: The NatIonal Danish endocarditis stUdieS (NIDUS) registry aims to investigate the mechanisms contributing to the increasing incidence of infective endocarditis (IE) and to discover risk factors associated to the course, treatment and clinical outcomes of the disease. METHODS: The NIDUS registry was created to investigate a nationwide unselected group of patients hospitalized for IE. The National Danish healthcare registries have been queried for validated IE diagnosis codes (International Classification of Disease, 10th edition [ICD-10]: DI33, DI38, and DI398). Subsequently, a team of 28 healthcare professionals, including experts in endocarditis, will systematically review and evaluate all identified patient records using the modified Duke Criteria and the 2015 European Society of Cardiology modified diagnostic criteria. The registry will contain all cases with definite or possible IE found in primary data sources in Denmark between January 1, 2016, and December 31, 2021. We will gather individual patient data, such as clinical, microbiological, and echocardiographic characteristics, treatment regimens, and clinical outcomes. A digital data collection form will be used to the gathering of data. A sample of approximately 4,300 individual patients will be evaluated using primary data sources. CONCLUSIONS AND PERSPECTIVES: The NIDUS registry will be the first comprehensive nationwide IE registry, contributing critical knowledge about the course, treatment, and clinical outcomes of the disease. Additionally, it will significantly aid in identifying areas in which future research is needed.

Clinical implementation of partial oral treatment in infective endocarditis: the Danish POETry study.

BACKGROUND AND AIMS: In the Partial Oral Treatment of Endocarditis (POET) trial, stabilized patients with left-sided infective endocarditis (IE) were randomized to oral step-down antibiotic therapy (PO) or conventional continued intravenous antibiotic treatment (IV), showing non-inferiority after 6 months. In this study, the first guideline-driven clinical implementation of the oral step-down POET regimen was examined. METHODS: Patients with IE, caused by Staphylococcus aureus, Enterococcus faecalis, Streptococcus spp. or coagulase-negative staphylococci diagnosed between May 2019 and December 2020 were possible candidates for initiation of oral step-down antibiotic therapy, at the discretion of the treating physician. The composite primary outcome in patients finalizing antibiotic treatment consisted of embolic events, unplanned cardiac surgery, relapse of bacteraemia and all-cause mortality within 6 months. RESULTS: A total of 562 patients [median age 74 years (IQR, interquartile range, 65-80), 70% males] with IE were possible candidates; PO was given to 240 (43%) patients and IV to 322 (57%) patients. More patients in the IV group had IE caused by S. aureus, or had an intra-cardiac abscess, or a pacemaker and more were surgically treated. The primary outcome occurred in 30 (13%) patients in the PO group and in 59 (18%) patients in the IV group (P = .051); in the PO group, 20 (8%) patients died vs. 46 (14%) patients in the IV group (P = .024). PO-treated patients had a shorter median length of stay [PO 24 days (IQR 17-36) vs. IV 43 days (IQR 32-51), P < .001]. CONCLUSIONS: After clinical implementation of the POET regimen almost half of the possible candidates with IE received oral step-down antibiotic therapy. Patients in the IV group had more serious risk factors for negative outcomes. At 6-month follow-up, there was a numerically but not statistically significant difference towards a lower incidence of the primary outcome, a lower incidence of all-cause mortality and a reduced length of stay in the PO group. Due to the observational design of the study, the lower mortality may to some extent reflect selection bias and unmeasured confounding. Clinical implementation of PO regimens seemed feasible and safe.

Attainment of Target Antibiotic Levels by Oral Treatment of Left-Sided Infective Endocarditis: A POET Substudy.

BACKGROUND: In the POET (Partial Oral Endocarditis Treatment) trial, oral step-down therapy was noninferior to full-length intravenous antibiotic administration. The aim of the present study was to perform pharmacokinetic/pharmacodynamic analyses for oral treatments of infective endocarditis to assess the probabilities of target attainment (PTAs). METHODS: Plasma concentrations of oral antibiotics were measured at day 1 and 5. Minimal inhibitory concentrations (MICs) were determined for the bacteria causing infective endocarditis (streptococci, staphylococci, or enterococci). Pharmacokinetic/pharmacodynamic targets were predefined according to literature using time above MIC or the ratio of area under the curve to MIC. Population pharmacokinetic modeling and pharmacokinetic/pharmacodynamic analyses were done for amoxicillin, dicloxacillin, linezolid, moxifloxacin, and rifampicin, and PTAs were calculated. RESULTS: A total of 236 patients participated in this POET substudy. For amoxicillin and linezolid, the PTAs were 88%-100%. For moxifloxacin and rifampicin, the PTAs were 71%-100%. Using a clinical breakpoint for staphylococci, the PTAs for dicloxacillin were 9%-17%.Seventy-four patients at day 1 and 65 patients at day 5 had available pharmacokinetic and MIC data for 2 oral antibiotics. Of those, 13 patients at day 1 and 14 patients at day 5 did only reach the target for 1 antibiotic. One patient did not reach target for any of the 2 antibiotics. CONCLUSIONS: For the individual orally administered antibiotic, the majority reached the target level. Patients with sub-target levels were compensated by the administration of 2 different antibiotics. The findings support the efficacy of oral step-down antibiotic treatment in patients with infective endocarditis.

Rifampicin reduces plasma concentration of linezolid in patients with infective endocarditis.

BACKGROUND: Linezolid in combination with rifampicin has been used in treatment of infective endocarditis especially for patients infected with staphylococci. OBJECTIVES: Because rifampicin has been reported to reduce the plasma concentration of linezolid, the present study aimed to characterize the population pharmacokinetics of linezolid for the purpose of quantifying an effect of rifampicin cotreatment. In addition, the possibility of compensation by dosage adjustments was evaluated. PATIENTS AND METHODS: Pharmacokinetic measurements were performed in 62 patients treated with linezolid for left-sided infective endocarditis in the Partial Oral Endocarditis Treatment (POET) trial. Fifteen patients were cotreated with rifampicin. A total of 437 linezolid plasma concentrations were obtained. The pharmacokinetic data were adequately described by a one-compartment model with first-order absorption and first-order elimination. RESULTS: We demonstrated a substantial increase of linezolid clearance by 150% (95% CI: 78%-251%), when combined with rifampicin. The final model was evaluated by goodness-of-fit plots showing an acceptable fit, and a visual predictive check validated the model. Model-based dosing simulations showed that rifampicin cotreatment decreased the PTA of linezolid from 94.3% to 34.9% and from 52.7% to 3.5% for MICs of 2 mg/L and 4 mg/L, respectively. CONCLUSIONS: A substantial interaction between linezolid and rifampicin was detected in patients with infective endocarditis, and the interaction was stronger than previously reported. Model-based simulations showed that increasing the linezolid dose might compensate without increasing the risk of adverse effects to the same degree.

Surgical treatment of patients with infective endocarditis: changes in temporal use, patient characteristics, and mortality-a nationwide study.

BACKGROUND: Valve surgery guidelines for infective endocarditis (IE) are unchanged over decades and nationwide data about the use of valve surgery do not exist. METHODS: We included patients with first-time IE (1999-2018) using Danish nationwide registries. Proportions of valve surgery were reported for calendar periods (1999-2003, 2004-2008, 2009-2013, 2014-2018). Comparing calendar periods in multivariable analyses, we computed likelihoods of valve surgery with logistic regression and rates of 30 day postoperative mortality with Cox regression. RESULTS: We included 8804 patients with first-time IE; 1981 (22.5%) underwent surgery during admission, decreasing by calendar periods (N = 360 [24.4%], N = 483 [24.0%], N = 553 [23.5%], N = 585 [19.7%], P = < 0.001 for trend). For patients undergoing valve surgery, median age increased from 59.7 to 66.9 years (P ≤ 0.001) and the proportion of males increased from 67.8% to 72.6% (P = 0.008) from 1999-2003 to 2014-2018. Compared with 1999-2003, associated likelihoods of valve surgery were: Odds ratio (OR) = 1.14 (95% CI: 0.96-1.35), OR = 1.20 (95% CI: 1.02-1.42), and OR = 1.10 (95% CI: 0.93-1.29) in 2004-2008, 2009-2013, and 2014-2018, respectively. 30 day postoperative mortalities were: 12.7%, 12.8%, 6.9%, and 9.7% by calendar periods. Compared with 1999-2003, associated mortality rates were: Hazard ratio (HR) = 0.96 (95% CI: 0.65-1.41), HR = 0.43 (95% CI: 0.28-0.67), and HR = 0.55 (95% CI 0.37-0.83) in 2004-2008, 2009-2013, and 2014-2018, respectively. CONCLUSIONS: On a nationwide scale, 22.5% of patients with IE underwent valve surgery. Patient characteristics changed considerably and use of valve surgery decreased over time. The adjusted likelihood of valve surgery was similar between calendar periods with a trend towards an increase while rates of 30 day postoperative mortality decreased.

Self-assessed health status and associated mortality in endocarditis: secondary findings from the POET trial.

PURPOSE: Self-assessed poor health status is associated with increased risk of mortality in several cardiovascular conditions, but has not been investigated in patients with endocarditis. We examined health status and mortality in patients with endocarditis. METHODS: This is a re-specified substudy of the randomized POET endocarditis trial, which included 400 patients. Patients completed the single-question self-assessed health status from the Short-Form 36 questionnaire at time of randomization and were categorized as having poor or non-poor (excellent/very good, good, or fair) health status. Self-assessed health status and all-cause mortality were examined by a Cox regression model. RESULTS: Self-assessed health status was completed by 266 (67%) patients with a mean age of 68.0 years (± 11.8), 54 (20%) were females, and 86 (32%) had one or more major concurrent medical conditions besides endocarditis. The self-assessed health status distribution was poor (n = 21, 8%) and non-poor (n = 245, 92%). The median follow-up was 3.3 years and death occurred in 9 (43%) and 48 (20%) patients reporting poor and non-poor health status, respectively, and mortality rates [mortality/100 person-years, 95% confidence interval (CI)] were 18.1 (95% CI 9.4-34.8) and 5.4 (95% CI 4.1-7.2), i.e., the crude hazard ratio for death was 3.4 (95% CI: 1.7-7.0, p < 0.01). CONCLUSION: Self-assessed poor health status compared with non-poor health status as assessed by a single question was associated with a threefold increased long-term mortality in patients with endocarditis. POET ClinicalTrials.gov number, NCT01375257. TRIAL REGISTRY: POET ClinicalTrials.gov number, NCT01375257.

Accelerated treatment of endocarditis-The POET II trial: Rationale and design of a randomized controlled trial.

BACKGROUND: The optimal antibiotic treatment length for infective endocarditis (IE) is uncertain. International guidelines recommend treatment duration of up to 6 weeks for patients with left-sided IE but are primarily based on historical data and expert opinion. Efficacies of modern therapies, fast recovery seen in many patients with IE, and complications to long hospital stays challenge the rationale for fixed treatment durations in all patients. OBJECTIVE: The objective was to conduct a noninferiority randomized controlled trial (acronym POET II) investigating the safety of accelerated (shortened) antibiotic therapy as compared to standard duration in patients with left-sided IE. METHODS: The POET II trial is a multicenter, multinational, open-label, noninferiority randomized controlled trial. Patients with definite left-sided IE due to Streptococcus spp, Staphylococcus aureus, or Enterococcus faecalis will be eligible for enrolment. Each patient will be randomized to accelerated antibiotic treatment or standard-length treatment (1:1) following clinical stabilization as defined by clinical parameters, laboratory values, and transesophageal echocardiography findings. Accelerated treatment will be between 2 and 4 weeks, whereas standard-length treatment will be between 4 and 6 weeks, depending on microbiologic etiology, complications, need for valve surgery, and prosthetic versus native valve endocarditis. The primary outcome is a composite of all-cause mortality, unplanned cardiac surgery, relapse of bacteremia, or embolization within 6 months of randomization. CONCLUSIONS: The POET II trial will investigate the safety of accelerated antibiotic therapy for patients with left-sided IE caused by Streptococcus spp, Staphylococcus aureus, or Enterococcus faecalis. The results of the POET II trial will improve the evidence base of treatment recommendations, and clinical practice may be altered.

Distribution and prognostic value of left ventricular global longitudinal strain in elderly patients with symptomatic severe aortic stenosis undergoing transcatheter aortic valve replacement.

AIMS: The aim of present study was to examine the preoperative prevalence and distribution of impaired left ventricular global longitudinal strain (LVGLS) in elderly patients with symptomatic aortic stenosis (AS) undergoing transcutaneous aortic valve replacement (TAVR) and to determine the predictive value of LVGLS on survival. METHODS: We included 411 patients with symptomatic severe AS treated with TAVR during a 5-year period, where a baseline echocardiography including LVGLS assessment was available. RESULTS: Mean age was 80.1 ± 7.1 years and aortic valve area (AVA) index 0.4 ± 0.1 cm2. 78 patients died during a median follow-up of 762 days. Mean left ventricular ejection fraction (LVEF) was 50 ± 13% and mean LVGLS was - 14.0%. LVEF was preserved in 60% of patients, while impaired LVGLS > - 18% was seen in 75% of the patients. Previous myocardial infarction, LVEF < 50%, LVGLS > - 14%, low gradient AS (< 4.0 m/s), tricuspid regurgitant gradient > 30 mmHg were identified as significant univariate predictors of all-cause mortality. On multivariate analysis LVGLS > - 14% (HR 1.79 [1.02-3.14], p = 0.04) was identified as the only independent variable associated with all-cause mortality. Reduced survival was observed with an impaired LVGLS > - 14% in the total population (p < 0.002) but also in patients with high AS gradient with preserved LVEF. LVGLS provided incremental prognostic value with respect to clinical characteristics, AVA and LVEF (χ2 19.9, p = 0.006). CONCLUSIONS: In patients with symptomatic AS undergoing TAVR, impaired LVGLS was highly prevalent despite preserved LVEF. LVGLS > - 14% was an independent predictor of all-cause mortality, and survival was reduced if LVGLS > - 14%.

Prevalence of infective endocarditis in patients with positive blood cultures: a Danish nationwide study.

AIMS: Increasing attention has been given to the risk of infective endocarditis (IE) in patients with certain blood stream infections (BSIs). Previous studies have been conducted on selected patient cohorts, yet unselected data are sparse. We aimed to investigate the prevalence of IE in BSIs with bacteria typically associated with IE. METHODS AND RESULTS: By crosslinking nationwide registries from 2010 to 2017, we identified patients with BSIs typically associated with IE: Enterococcus faecalis (E. faecalis), Staphylococcus aureus (S. aureus), Streptococcus spp., and coagulase negative staphylococci (CoNS) and examined the concurrent IE prevalence. A trend test was used to examine temporal changes in the prevalence of IE. In total 69 021, distributed with 15 350, 16 726, 19 251, and 17 694 BSIs were identified in the periods of 2010-2011, 2012-2013, 2014-2015, and 2016-2017, respectively. Patients with E. faecalis had the highest prevalence of IE (16.7%) followed by S. aureus (10.1%), Streptococcus spp. (7.3%), and CoNS (1.6%). Throughout the study period, the prevalence of IE among patients with E. faecalis and Streptococcus spp. increased significantly (P = 0.0005 and P = 0.03, respectively). Male patients had a higher prevalence of IE for E. faecalis, Streptococcus spp., and CoNS compared with females. A significant increase in the prevalence of IE was seen for E. faecalis, Streptococcus spp., and CoNS with increasing age. CONCLUSION: For E. faecalis BSI, 1 in 6 had IE, for S. aureus BSI 1 in 10 had IE, and for Streptococcus spp. 1 in 14 had IE. Our results suggest that screening for IE seems reasonable in patients with E. faecalis BSI, S. aureus BSI, or Streptococcus spp. BSI.

Proteomics of the Rat Myocardium during Development of Type 2 Diabetes Mellitus Reveals Progressive Alterations in Major Metabolic Pathways.

Congestive heart failure and poor clinical outcome after myocardial infarction are known complications in patients with type-2 diabetes mellitus (T2DM). Protein alterations may be involved in the mechanisms underlying these disarrays in the diabetic heart. Here we map proteins involved in intracellular metabolic pathways in the Zucker diabetic fatty rat heart as T2DM develops using MS based proteomics. The prediabetic state only induced minor pathway changes, whereas onset and late T2DM caused pronounced perturbations. Two actin-associated proteins, ARPC2 and TPM3, were up-regulated at the prediabetic state indicating increased actin dynamics. All differentially regulated proteins involved in fatty acid metabolism, both peroxisomal and mitochondrial, were up-regulated at late T2DM, whereas enzymes of branched chain amino acid degradation were all down-regulated. At both onset and late T2DM, two members of the serine protease inhibitor superfamily, SERPINA3K and SERPINA3L, were down-regulated. Furthermore, we found alterations in proteins involved in clearance of advanced glycation end-products and lipotoxicity, DCXR and CBR1, at both onset and late T2DM. These proteins deserve elucidation with regard to their role in T2DM pathogenesis and their respective role in the deterioration of the diabetic heart. Data are available via ProteomeXchange with identifiers PXD009538, PXD009554, and PXD009555.

Pre-ischaemic mitochondrial substrate constraint by inhibition of malate-aspartate shuttle preserves mitochondrial function after ischaemia-reperfusion.

KEY POINTS: Pre-ischaemic administration of aminooxiacetate (AOA), an inhibitor of the malate-aspartate shuttle (MAS), provides cardioprotection against ischaemia-reperfusion injury. The underlying mechanism remains unknown. We examined whether transient inhibition of the MAS during ischaemia and early reperfusion by AOA treatment could prevent mitochondrial damage at later reperfusion. The AOA treatment preserved mitochondrial respiratory capacity with reduced mitochondrial oxidative stress during late reperfusion to the same extent as ischaemic preconditioning (IPC). However, AOA treatment, but not IPC, reduced the myocardial interstitial concentration of tricarboxylic acid cycle intermediates at the onset of reperfusion. The results obtained in the present study demonstrate that metabolic regulation by inhibition of the MAS at the onset of reperfusion may be beneficial for the preservation of mitochondrial function during late reperfusion in an IR-injured heart. ABSTRACT: Mitochondrial dysfunction plays a central role in ischaemia-reperfusion (IR) injury. Pre-ischaemic administration of aminooxyacetate (AOA), an inhibitor of the malate-aspartate shuttle (MAS), provides cardioprotection against IR injury, although the underlying mechanism remains unknown. We hypothesized that a transient inhibition of the MAS during ischaemia and early reperfusion could preserve mitochondrial function at later phase of reperfusion in the IR-injured heart to the same extent as ischaemic preconditioning (IPC), which is a well-validated cardioprotective strategy against IR injury. In the present study, we show that pre-ischaemic administration of AOA preserved mitochondrial complex I-linked state 3 respiration and fatty acid oxidation during late reperfusion in IR-injured isolated rat hearts. AOA treatment also attenuated the excessive emission of mitochondrial reactive oxygen species during state 3 with complex I-linked substrates during late reperfusion, which was consistent with reduced oxidative damage in the IR-injured heart. As a result, AOA treatment reduced infarct size after reperfusion. These protective effects of MAS inhibition on the mitochondria were similar to those of IPC. Intriguingly, the protection of mitochondrial function by AOA treatment appears to be different from that of IPC because AOA treatment, but not IPC, downregulated myocardial tricarboxilic acid (TCA)-cycle intermediates at the onset of reperfusion. MAS inhibition thus preserved mitochondrial respiratory capacity and decreased mitochondrial oxidative stress during late reperfusion in the IR-injured heart, at least in part, via metabolic regulation of TCA cycle intermediates in the mitochondria at the onset of reperfusion.

Inhibition of KV7 Channels Protects the Rat Heart against Myocardial Ischemia and Reperfusion Injury.

The voltage-gated KV7 (KCNQ) potassium channels are activated by ischemia and involved in hypoxic vasodilatation. We investigated the effect of KV7 channel modulation on cardiac ischemia and reperfusion injury and its interaction with cardioprotection by ischemic preconditioning (IPC). Reverse-transcription polymerase chain reaction revealed expression of KV7.1, KV7.4, and KV7.5 in the left anterior descending rat coronary artery and all KV7 subtypes (KV7.1-KV7.5) in the left and right ventricles of the heart. Isolated hearts were subjected to no-flow global ischemia and reperfusion with and without IPC. Infarct size was quantified by 2,3,5-triphenyltetrazolium chloride staining. Two blockers of KV7 channels, XE991 [10,10-bis(4-pyridinylmethyl)-9(10H)-anthracenone] (10 µM) and linopirdine (10 µM), reduced infarct size and exerted additive infarct reduction to IPC. An opener of KV7 channels, flupirtine (10 µM) abolished infarct size reduction by IPC. Hemodynamics were measured using a catheter inserted in the left ventricle and postischemic left ventricular recovery improved in accordance with reduction of infarct size and deteriorated with increased infarct size. XE991 (10 µM) reduced coronary flow in the reperfusion phase and inhibited vasodilatation in isolated small branches of the left anterior descending coronary artery during both simulated ischemia and reoxygenation. KV7 channels are expressed in rat coronary arteries and myocardium. Inhibition of KV7 channels exerts cardioprotection and opening of KV7 channels abrogates cardioprotection by IPC. Although safety issues should be further addressed, our findings suggest a potential role for KV7 blockers in the treatment of ischemia-reperfusion injury.

Changes and Prognostic Implications of Myocardial Work in Aortic Stenosis Subtypes Undergoing Transcatheter Valve Implantation.

Background: Evaluation of left ventricle (LV) systolic function in patients with aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI) is challenging, as LV ejection fraction (LVEF) and global longitudinal strain are afterload dependent. LV global work indices (GWIs) estimate the afterload corrected systolic function. Objectives: The purpose of this study was to evaluate changes in and prognostic implications of GWIs in subtypes of AS patients before and 1 month after TAVI. Methods: We included 473 patients undergoing TAVI. GWI was estimated using strain imaging and by adding the aortic valve mean gradient to the systolic blood pressure. The primary endpoint was all-cause mortality, evaluated by Cox proportional hazards and Kaplan-Meier curves. Results: High gradient, low flow/low gradient, and normal flow/low gradient AS was found in 48%, 27%, and 25%. In patients with LVEF ≥50% delta GWI decreased from preoperative assessment to 1-month follow-up across all subtypes; high gradient (-353 ± 589 mm Hg%, P < 0.01), low flow/low gradient (-151 ± 652 mm Hg%, P = 0.13), and normal flow/low gradient (-348 ± 606 mm Hg%, P < 0.01). For patients with LVEF <50% delta GWI increased; high gradient 127 ± 491 mm Hg%, P = 0.05; low flow/low gradient 106 ± 510 mm Hg%, P = 0.06; normal flow/low gradient 107 ± 550 mm Hg%, P < 0.27. The median follow-up time was 60 months (IQR: 45-69 months). Each step of 100 mm Hg% higher GWI at pre-TAVI assessment was associated with a reduction in all-cause mortality in multivariable analysis (HR: 0.96 [95% CI: 0.92-1.00], P = 0.033). Conclusions: GWI increases in patients with reduced LVEF after TAVI across AS subtypes whereas GWI decreases in patients with preserved LVEF. Assessment of GWI offers additional prognostic implications beyond LVEF and global longitudinal strain.

Impact of mandatory preoperative dental screening on post-procedural risk of infective endocarditis in patients undergoing transcatheter aortic valve implantation: a nationwide retrospective observational study.

Background: Guidelines recommend preoperative dental screening (PDS) prior to cardiac valve surgery, to reduce the incidence of prosthetic valve infective endocarditis (IE). However, limited data support these recommendations, particular in patients undergoing transcatheter aortic valve implantation (TAVI). We aimed to investigate the effect of mandatory PDS on risk of IE in patients undergoing TAVI. Methods: In this observational study, a total of 1133 patients undergoing TAVI in Western-Denmark from 2020 to 2022 were included. Patients were categorized based on two implemented PDS practices: mandatory PDS (MPDS group), and no referral for PDS (NPDS group). Outcome data were retrieved from Danish registries and confirmed using medical records. The primary outcome was incidence of IE. Secondary outcomes were all-cause mortality and composite outcome of all-cause mortality and IE. Findings: Of 568 patients in the MPDS group 126 (22.2%) underwent subsequent oral dental surgery, compared to 8 (1.4%) among 565 patients in the NPDS group. During a median follow-up of 1.9 years (interquartile range 1.4-2.5 years), 31 (2.7%) developed IE. The yearly incidence IE rate was 1.4% (0.8-2.3) and 1.5% (0.8-2.4) in MPDS and NPDS, respectively, p = 0.86. All-cause mortality rates were similar between groups (estimated 2-year overall mortality of 6.7% (4.8-9.2) vs. 4.7% (3.2-6.9), MPDS and NPDS, respectively, p = 0.15). Consistent findings were found in 712 propensity score-matched patients. Interpretation: Mandatory PDS did not demonstrate reduced risk of IE or all-cause mortality compared to targeted PDS in patients undergoing TAVI. Funding: The funder had no role in the study design, data management, or writing.

Association Between Vegetation Size and Outcome in the Partial Oral Antibiotic Endocarditis Treatment Trial.

Step-down oral antibiotic therapy is associated with a non-inferior long-term outcome compared with continued intravenous antibiotic therapy in the treatment of left-sided infective endocarditis. We aimed to analyze whether step-down oral therapy compared with continued intravenous antibiotic therapy is also associated with a non-inferior outcome in patients with large vegetations (vegetation length ≥ 10 mm) or among patients who underwent surgery before step-down oral therapy. We included patients without presence of aortic root abscess at diagnosis from the POET (Partial Oral Antibiotic Endocarditis Treatment) study. Multivariable Cox regression analyses were used to find associations between large vegetation, cardiac surgery, step-down oral therapy, and the primary end point (composite of all-cause mortality, unplanned cardiac surgery, embolic event, or relapse of positive blood cultures during follow-up). A total of 368 patients (age 68 ± 12, 77% men) were included. Patients with large vegetations (n = 124) were more likely to undergo surgery compared with patients with small vegetations (n = 244) (65% vs 20%, p <0.001). During a median 1,406 days of follow-up, 146 patients reached the primary end point. Large vegetations were not associated with the primary end point (hazard ratio 0.74, 95% confidence interval 0.47 to 1.18, p = 0.21). Step-down oral therapy was non-inferior to continued intravenous antibiotic in all subgroups when stratified by the presence of a large vegetation at baseline and early cardiac surgery. Step-down oral therapy is safe in the presence of a large vegetation at diagnosis and among patients who underwent early cardiac surgery.

Prognostic implications of residual left ventricular hypertrophy and systolic dysfunction in aortic stenosis following transcatheter aortic valve replacement.

The impact of left ventricle (LV) hypertrophy (LVH) regression on contractility-associated measures, the extent of residual cardiac dysfunction and prognostic implications after the initial remodeling process after transcatheter aortic valve replacement (TAVR) has not been investigated. We aimed to assess whether greater LV mass regression from pre-TAVR to 12-months after TAVR was associated with increased systolic function; and assess the prognostic value of residual LVH, systolic function and contractility-associated measures 12-months after TAVR. A total of 439 symptomatic patients were included and examined by echocardiography. LVH regression was assessed as percentage change in LV mass index (LVMi) from baseline to 12-months after TAVR. Midwall fractional shortening (mFS) and stress-corrected (SC-mFS) were used as contractility-associated measures. Primary outcome was all-cause mortality. SC-mFS increased from 0.94 (0.7) at baseline (BS) to 1.22 (0.7) (p < 0.05) 12-months after TAVR for patients with the most LVH regression, compared to patients with no LV regression (BS 1.06 (0.7) to 1.04 (0.5), NS). At 12-months after TAVR, multivariate analysis showed independent prognostic value of LVEF < 50% or GLS < 15% (HR 1.59, p = 0.049) and mFS < 14% (HR 1.99, p = 0.002) for future all cause death. LVH regression in AS after TAVR is associated with significant improvements of LV systolic function in contrast to patients without LV regression. Residual LVH and subsequent LV systolic dysfunction is substantial 12 months after TAVR and are associated with reduced survival. Impaired mFS and the combination of abnormal LVEF or GLS independently predicted all-cause mortality beyond 12 months after TAVR.

Ischemic preconditioning reduces right ventricular infarct size through opening of mitochondrial potassium channels.

OBJECTIVES: We investigated whether ischemic preconditioning (IPC) protects the right ventricular (RV) myocardium against ischemic injury in hearts treated with the specific mitochondrial ATP-sensitive potassium (K(ATP)) channel blocker 5-hydroxydecanoate (5-HD). METHODS: Hearts from male Wistar rats (300 g, n = 39) were isolated and perfused with Krebs-Henseleit buffer and randomized to no IPC (control, n = 16), IPC (n = 16) or IPC preceded by addition of 5-HD (100 µM, n = 7). IPC consisted of 2 × 5 min of global ischemia followed by 40 min of global ischemia and 120 min of reperfusion. The effect of IPC on RV myocardial infarct size was evaluated by measurement of the infarct size/area-at-risk ratio (RVIS/AAR). Postischemic RV function was evaluated by RV pressures. RESULTS: IPC produced a marked decrease in RVIS/AAR (24.4 ± 8.1 vs. 42.6 ± 10.6%, p < 0.0001) and improved hemodynamic recovery of RV contractile function compared with the control group. We found no difference in RVIS/AAR (45.2 ± 4.4 vs. 42.6 ± 10.6, p > 0.05) or hemodynamic recovery between IPC + 5-HD and control hearts. Blockade of mitochondrial K(ATP) channels by 5-HD abolished the cardioprotective response to IPC. CONCLUSION: IPC reduces RV myocardial infarct size and improves postischemic RV contractile function in the isolated rat heart, possibly through opening of the mitochondrial K(ATP) channel.

Effects of fatty acids on cardioprotection by pre-ischaemic inhibition of the malate-aspartate shuttle.

1. The malate-aspartate shuttle (MAS) is the main pathway for balancing extra- and intramitochondrial glucose metabolism. Pre-ischaemic shutdown of the MAS by aminooxyacetate (AOA) mimics ischaemic preconditioning (IPC) in rat glucose-perfused hearts. The aim of the present study was to determine the effects of fatty acids (FA) on cardioprotection by pre-ischaemic inhibition of the MAS. 2. Isolated rat hearts were divided into four groups (control; pre-ischaemic AOA (0.2 mmol/L); IPC; and AOA + IPC) and were perfused with 11 mmol/L glucose, 3% bovine serum albumin plus 0, 0.4 or 1.2 mmol/L FA. The perfusion protocol included 30 min global no-flow ischaemia and 120 min reperfusion. Infarct size (IS), haemodynamic recovery, glucose oxidation and lactate release were evaluated in all four groups. 3. Pre-ischaemic AOA reduced the IS of the left ventricle in hearts perfused with 0, 0.4 and 1.2 mmol/L FA compared with that in control hearts (26 ± 2% vs 53 ± 4%, 29 ± 3% vs 53 ± 4% and 61 ± 4% vs 81 ± 3%, respectively; P < 0.01 for all). After 2 h reperfusion, AOA improved haemodynamic recovery in the absence (52 ± 2 vs 27 ± 3 mmHg in the AOA and control groups, respectively; P < 0.001) but not in the presence, of FA. Both IPC and AOA + IPC reduced IS and improved haemodynamic recovery regardless of FA levels. Postischaemic glucose oxidation was suppressed by FA and did not differ significantly between the different groups. 4. In conclusion, the reduction in IS induced by pre-ischaemic MAS shutdown is not compromised by physiological FA concentrations. Transient MAS shutdown may be involved in IPC, but is not sufficient on its own as the underlying mechanism for IPC.

Severity of anaemia and association with all-cause mortality in patients with medically managed left-sided endocarditis.

OBJECTIVE: To assess the prevalence and severity of anaemia in patients with left-sided infective endocarditis (IE) and association with mortality. METHODS: In the Partial Oral versus Intravenous Antibiotic Treatment of Endocarditis trial, 400 patients with IE were randomised to conventional or partial oral antibiotic treatment after stabilisation of infection, showing non-inferiority. Haemoglobin (Hgb) levels were measured at randomisation. Primary outcomes were all-cause mortality after 6 months and 3 years. Patients who underwent valve surgery were excluded due to competing reasons for anaemia. RESULTS: Out of 400 patients with IE, 248 (mean age 70.6 years (SD 11.1), 62 women (25.0%)) were medically managed; 37 (14.9%) patients had no anaemia, 139 (56.1%) had mild anaemia (Hgb <8.1 mmol/L in men and Hgb <7.5 mmol/L in women and Hgb ≥6.2 mmol/L) and 72 (29.0%) had moderate to severe anaemia (Hgb <6.2 mmol/L). Mortality rates in patients with no anaemia, mild anaemia and moderate to severe anaemia were 2.7%, 3.6% and 15.3% at 6-month follow-up and 13.5%, 20.1% and 34.7% at 3-year follow-up, respectively. Moderate to severe anaemia was associated with higher mortality after 6 months (HR 4.81, 95% CI 1.78 to 13.0, p=0.002) and after 3 years (HR 2.14, 95% CI 1.27 to 3.60, p=0.004) and remained significant after multivariable adjustment. CONCLUSION: Moderate to severe anaemia was present in 29% of patients with medically treated IE after stabilisation of infection and was independently associated with higher mortality within the following 3 years. Further investigations are warranted to determine whether intensified treatment of anaemia in patients with IE might improve outcome.