Oxidized high-density lipoprotein associates with atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is the most common heart arrhythmia and considered to be a progressive chronic disease associated with increased morbidity and mortality. Recent data suggest a link between inflammation, oxidative stress, and AF, although the underlying mechanisms are not fully understood. Because oxidized lipoproteins cause structural damage and electrophysiologic changes in cardiomyocytes, it is feasible that the transformation of atheroprotective high-density lipoprotein (HDL) into dysfunctional HDL contributes to the development of AF.

OBJECTIVE

The purpose of this study was to determine whether a reduced antioxidant function of HDL is associated with the presence of AF.

METHODS

In this multicenter cross-sectional cohort study, we assessed HDL function in sera of 1206 participants. Patients were divided into groups according to the presence of AF (n = 233) or no AF (n = 973). A validated cell-free biochemical assay was used to determine reduced HDL antioxidant function as assessed by increased normalized HDL lipid peroxide content (nHDLox).

RESULTS

Participants with AF had a 9% higher mean relative nHDLox compared to persons without AF (P = .025). nHDLox was strongly associated with AF in all models of logistic regression, including the analysis adjusted for age, sex, and risk factors for AF (all P ≤.01).

CONCLUSION

Reduced antioxidant HDL function is associated with the presence of AF, which supports growing evidence that impaired lipoprotein function is linked to electrophysiological changes in cardiomyocytes. nHDLox is one of several contributors to the initiation and perpetuation of AF.

Coronary microthrombi in the failing human heart: the role of von Willebrand factor and PECAM-1

The recognition of microthrombi in the heart microcirculation has recently emerged from studies in COVID-19 decedents. The present study investigated the ultrastructure of coronary microthrombi in heart failure (HF) due to cardiomyopathies that are unrelated to COVID-19 infection. In addition, we have investigated the role of von Willebrand factor (VWF) and PECAM-1 in microthrombus formation. We used electron microscopy to investigate the occurrence of microthrombi in patients with HF due to dilated (DCM, n = 7), inflammatory (MYO, n = 6) and ischemic (ICM, n = 7) cardiomyopathy and 4 control patients. VWF and PECAM-1 was studied by quantitative immunohistochemistry and Western blot. In comparison to control, the number of microthrombi was increased 7-9 times in HF. This was associated with a 3.5-fold increase in the number of Weibel-Palade bodies (WPb) in DCM and MYO compared to control. A fivefold increase in WPb in ICM was significantly different from control, DCM and MYO. In Western blot, VWF was increased twofold in DCM and MYO, and more than threefold in ICM. The difference between ICM and DCM and MYO was statistically significant. These results were confirmed by quantitative immunohistochemistry. Compared to control, PECAM-1 was by approximatively threefold increased in all groups of patients. This is the first study to demonstrate the occurrence of microthrombi in the failing human heart. The occurrence of microthrombi is associated with increased expression of VWF and the number of WPb, being more pronounced in ICM. These changes are likely not compensated by increases in PECAM-1 expression.

Atrial fibrillation in human patients is associated with increased collagen type V and TGFbeta1

Background and aim

Atrial fibrosis is an important factor in initiating and maintaining atrial fibrillation (AF). Collagen V belongs to fibrillar collagens. There are, however no data on collagen V in AF. The aim of this work was to study the quantity of collagen V and its relationship with the number of fibroblasts and TGF- b 1 expression in patients in sinus rhythm (SR) and in patients with atrial fibrillation (AF).

Methods

We used quantitative immuhistochemistry to study collagen V in right and left atrial biopsies obtained from 35 patients in SR, 35 patients with paroxysmal AF (pAF) and 27 patients with chronic, long-standing persistent AF (cAF). In addition, we have quantified the number of vimentin-positive fibroblasts and expression levels of TGF-β1.

Results

Compared to patients in SR, collagen V was increased 1.8- and 3.1-fold in patients with pAF and cAF, respectively. In comparison with SR patients, the number of vimentin-positive cells increased significantly 1.46- and 1.8-fold in pAF and cAF patients, respectively.Compared to SR patients, expression levels of TGF-ß1, expressed as fluorescence units per tissue area, was significantly increased by 77 % and 300 % in patients with pAF and cAF, respectively. Similar to intensity measurements, the number of TGFß1-positive cells per 1 mm2 atrial tissue increased significantly from 35.5 ± 5.5 cells in SR patients to 61.9 ± 12.4 cells in pAF and 131.5 ± 23.5 cells in cAF. In both types of measurements, there was a statistically significant difference between pAF and cAF groups.

Conclusions

This is the first study to show that AF is associated with increased expression levels of collagen V and TGF-ß1indicating its role in the pathogenesis of atrial fibrosis. In addition, increases in collagen V correlate with increased number of fibroblasts and TGF-β1 and are more pronounced in cAF patients than those in pAF patients.

Dysfunctional high-density lipoprotein in chronic inflammatory rheumatic diseases

Background

The mechanism explaining low cholesterol concentrations in chronic inflammatory rheumatic disease (CIRD) is incompletely understood. We hypothesized that chronic inflammation impairs the functionality of high-density lipoprotein (HDL), for example, by oxidative processes.

Objectives

Assessment of oxidized HDL (HDLox), a marker of dysfunctional HDL, in newly diagnosed patients with CIRD before and after initiation of immunosuppressive therapy and comparison of HDLox values of patients with CIRD to non-CIRD controls.

Design

Prospective observational trial.

Methods

The study was conducted on 44 newly diagnosed CIRD patients, who were initiated on immunosuppressive therapy (baseline). A total of 136 patients without CIRD served as control. Lipid profiles including HDLox levels and C-reactive protein (CRP) were measured in both groups at baseline. In CIRD patients, measurements were repeated 12 weeks after baseline. Validated outcome tools for disease activity and function were assessed at baseline and 12 weeks.

Results

A total of 33 (75%) patients with rheumatoid arthritis, 7(16%) with axial spondyloarthritis, and 4 (9%) with systemic lupus erythematosus were included. Groups were comparable for age and BMI. CIRD patients had higher HDLox concentrations (1.57 versus 0.78, p = 0.02) and tended to have lower low-density lipoprotein cholesterol, HDL cholesterol, and cholesterol concentrations compared to controls. HDLox (1.57 versus 1.4, p = 0.26) and CRP levels (2.1 versus 0.7 mg/dl, p < 0.01) decreased in CIRD patients from baseline to follow-up.

Conclusion

CIRD is associated with an impairment of the anti-inflammatory properties of HDL as reflected by an increase in HDLox concentrations. This effect may contribute to the increased cardiovascular risk in chronic inflammatory diseases.

Leukocyte telomere length and mitochondrial DNA copy number associate with endothelial function in aging-related cardiovascular disease

Background

We investigated the association between leukocyte telomere length, mitochondrial DNA copy number, and endothelial function in patients with aging-related cardiovascular disease (CVD).

Methods

In total 430 patients with CVD and healthy persons were enrolled in the current study. Peripheral blood was drawn by routine venipuncture procedure. Plasma and peripheral blood mononuclear cells (PBMCs) were collected. Cell-free genomic DNA (cfDNA) and leukocytic genomic DNA (leuDNA) were extracted from plasma and PBMCs, respectively. Relative telomere length (TL) and mitochondrial DNA copy number (mtDNA-CN) were analyzed using quantitative polymerase chain reaction. Endothelial function was evaluated by measuring flow-mediated dilation (FMD). The correlation between TL of cfDNA (cf-TL), mtDNA-CN of cfDNA (cf-mtDNA), TL of leuDNA (leu-TL), mtDNA-CN of leuDNA (leu-mtDNA), age, and FMD were analyzed based on Spearman's rank correlation. The association between cf-TL, cf-mtDNA, leu-TL, leu-mtDNA, age, gender, and FMD were explored using multiple linear regression analysis.

Results

cf-TL positively correlated with cf-mtDNA (r = 0.1834, P = 0.0273), and leu-TL positively correlated with leu-mtDNA (r = 0.1244, P = 0.0109). In addition, both leu-TL (r = 0.1489, P = 0.0022) and leu-mtDNA (r = 0.1929, P < 0.0001) positively correlated with FMD. In a multiple linear regression analysis model, both leu-TL (β = 0.229, P = 0.002) and leu-mtDNA (β = 0.198, P = 0.008) were positively associated with FMD. In contrast, age was inversely associated with FMD (β = -0.426, P < 0.0001).

Conclusion

TL positively correlates mtDNA-CN in both cfDNA and leuDNA. leu-TL and leu-mtDNA can be regarded as novel biomarkers of endothelial dysfunction.

Defibrillator exchange in the elderly

Background

Implantable cardioverter-defibrillator (ICD) therapy in elderly patients is controversial because survival benefits might be attenuated by nonarrhythmic causes of death.

Objective

The purpose of this study was to investigate the outcome of septuagenarians and octogenarians after ICD generator exchange (GE).

Methods

A total of 506 patients undergoing elective GE were analyzed to determine the incidence of ICD shocks and/or survival after GE. Patients were divided into a septuagenarian group (age 70-79 years) and an octogenarian group (age ≥80 years). The primary endpoint was death from any cause. Secondary endpoints were survival after appropriate ICD shock and death without experiencing ICD shocks after GE ("prior death").

Results

The association of the ICD with all-cause mortality and arrhythmic death was determined for septuagenarians and octogenarians. Comparing both groups, similar left ventricular ejection fraction (35.6% ± 11.2% vs 32.4% ± 8.9%) and baseline prevalence of New York Heart Association functional class III or IV heart failure (17.1% vs 14.7%) were found. During the entire follow-up period of the study, 42.5% of patients in the septuagenarian group died compared to 79% in the octogenarian group (P <.01). Prior death was significantly more frequent in both age groups than were appropriate ICD shocks. Predictors of mortality were common in both groups and included advanced heart failure, peripheral arterial disease, and renal failure.

Conclusion

In clinical practice, decision-making for ICD GE among the elderly should be considered carefully for individual patients.

Association of plasma propionate concentration with coronary artery disease in a large cross-sectional study

Background

Microbiome has been linked to the pathogenesis of coronary artery disease (CAD) but data providing direct evidence for an association of short-chain fatty acids (SCFA) with CAD are lacking. This study aimed to evaluate the role of propionate, the most important SCFA in patients with CAD.

Methods

We performed a cross-sectional study enrolling patients admitted for invasive coronary angiography in two university hospitals in Germany. Patients with known or suspected CAD and risk factors for cardiovascular disease were prospectively recruited. Blood sampling was performed after overnight fasting and before invasive procedures. Measurement of propionate was performed by liquid chromatography.

Results

The study included 1,253 patients (median [IQR], 67 [58-76] years; 799 men [64%]). A total of 739 had invasively confirmed CAD with at least one coronary artery stenosis ≥50% and 514 had exclusion of CAD. CAD patients had significant lower levels of propionate (median 5.75 μM, IQR, 4.1-7.6) compared to the non-CAD groups 6.53 μM (4.6-8.6, p < 0.001). Multivariate linear regression analysis revealed an odds ratio of 0.94 (CI 0.90-0.98, p = 0.002) for propionate as predictor of CAD. The odds ratio was further decreased to 0.45 (CI 0.31-0.65, p < 0.001) when comparing patients in the lowest quartile of propionate with those with higher levels of propionate.

Conclusion

The study provides large-scale in vivo data for the association of propionate to manifest coronary artery disease, independent of other traditional cardiovascular risk factors.

Association of propionate with coronary artery disease in a large cross-sectional study

Background

Microbiome has been linked to the pathogenesis of coronary artery disease (CAD) but data providing direct evidence for an association of short-chain fatty acids (SCFA) like propionate with CAD are lacking.

Purpose

To study the association of propionate in blood samples with the presence of CAD

Methods

This was a cross-sectional study enrolling patients admitted to invasive coronary angiography in a university hospital in Germany. Patients were prospectively recruited between from March 2017 to January 2020. Patients with known or suspected CAD and risk factors for cardiovascular diseases were screened for eligibility to participate in the trial. Main exclusion criteria were inflammatory/rheumatic disease, active cancer disease and acute infection. Blood sampling was performed after overnight fasting and before invasive procedures. Measurement of propionate was performed though liquid chromatography.

Results

The study included 691 patients (median n [IQR] age, 69 [60–78] years; 406 men [59%]). A total of 368 had invasively confirmed CAD with at least one coronary artery stenosis ≥50% and 323 had non CAD and 194 had invasively excluded CAD. 129 additional patients without suspicion for CAD and without diabetes/smoking were also recruited in the no CAD group. CAD patients had significant lower levels of propionate (median) 6.08 μM (IQR, 4.31–7.65) compared to the no CAD groups 6.92 μM (4.89–9.25, &lt;0.05). Linear regression multivariate analysis adjusted for age, gender, body mass index, hypertension, smoking, diabetes and hyperlipidemia revealed an odds ratio of 0.92 (CI 0.89–0,96, p&lt;0.001) for propionate as predictor of CAD.

Conclusions

The study provides large-scale data for a protective role of propionate in the development of CAD, independent of the presence of other known cardiovascular risk factors.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Internal Grant, Medical School of Brandenburg

Reduced antioxiadant high-density lipoprotein function in patients with acute coronary syndrome

Background

High-density lipoprotein (HDL) function rather than concentration plays an important role in the pathogenesis of cardiovascular diseases associated with oxidative stress and inflammation such as coronary artery disease (CAD). In the last years, inflammation has been identified to have a pivotal role in the pathogenesis of acute coronary syndrome (ACS).

Purpose

The aim of the present study is to determine whether reduced antioxidant function of HDL is associated with ACS.

Methods

197 patients with ACS were prospectively recruited and blood samples were taken in the first 48h after enrollment. Patients with chronic coronary syndrome CCS (n=727) and with invasively excluded CAD (no CAD, n=498) from another cohort from our group served as control patients. A validated cell-free biochemical assay was used to determine reduced HDL antioxidant function as assessed by increased HDL-lipid peroxide content (HDLox) normalized by HDL-C levels and the mean value of a pooled serum control from healthy participants (nHDLox; no units).

Results

Patients with ACS had significantly increased HDLox blood levels compared to patients with CCS and to patients without CAD (p&lt;0.001, Figure 1A). Prior intake of statins did not influenc the differences of HDLox among the groups (Figure 1B). In the regression analysis increased HDLox was a strong risk factor for the presence of ACS compared to CCS (odds ratio 4.09 (2.98–5.62), p&lt;0.001, Figure 2).

Conclusions

HDL peroxidation is associated with the presence of ACS independent of the presence of other traditional risk factors.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): BIOX

Understanding the importance of social determinants and rurality for the long-term outcome after acute myocardial infarction: study protocol for a single-centre cohort study

INTRODUCTION

Acute myocardial infarction (AMI) is a major public health issue in Germany with considerable regional differences in morbidity and mortality. Possible reasons for regional differences include a higher prevalence of cardiovascular risk factors, infrastructural deficits, different levels of healthcare quality or social determinants. We aim to study associations of social determinants and of rural infrastructure with the quality of medical care (eg, time to reperfusion or medication adherence) and on the long-term outcome after myocardial infarction.

METHODS AND ANALYSIS

We will employ a prospective cohort study design. Patients who are admitted with AMI will be invited to participate. We aim to recruit a total of 1000 participants over the course of 5 years. Information on outpatient care prior to AMI, acute healthcare of AMI, healthcare-related environmental factors and social determinants will be collected. Baseline data will be assessed in interviews and from the electronic data system of the hospital. Follow-up will be conducted after an observation period of 1 year via patient interviews. The outcomes of interest are cardiac and all-cause mortality, changes in quality of life, changes in health status of heart failure, major adverse cardiovascular events and participation in rehabilitation programmes.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Ethics Committee of Brandenburg Medical School (reference: E-01-20200923). Research findings will be disseminated and shared in different ways and include presenting at international and national conferences, publishing in peer-reviewed journals and facilitating dissemination workshops within local communities with patients and healthcare professionals.

TRIALS REGISTRATION NUMBER

DRKS00024463.

Contextualising the association of socioeconomic deprivation with hospitalisation rates of myocardial infarction in a rural area in eastern Germany

INTRODUCTION

Evidence on the association of socioeconomic deprivation with occurrence of acute myocardial infarction (AMI) is available from international studies and urban settings in western Germany. This study aimed to assess this association based on small geographical areas in a rural setting in eastern Germany.

METHODS

This study used routine data of all patients with AMI who were treated in the Hospital Brandenburg in the city of Brandenburg, Germany, between May 2019 and May 2020. Hospitalisation rates of AMI were calculated for postal code regions that were located within the catchment area of the Hospital Brandenburg. Poisson regression was used to compare hospitalisation rates in areas with medium socioeconomic deprivation to areas with high deprivation, controlling for age group, sex and period (before or during COVID-19 pandemic). Publicly available social, infrastructure and healthcare-related features were mapped to characterise the study region.

RESULTS

In total, 265 cases of AMI were registered in the study area, which comprised 116,126 inhabitants. The city of Brandenburg was characterised by the highest level of socioeconomic deprivation, while neighbouring areas showed a rural settlement structure and medium levels of deprivation. The number of general practitioners per 10 000 inhabitants did not differ between both areas. The adjusted rate ratio comparing hospitalisations due to AMI in areas with medium socioeconomic deprivation to areas with high socioeconomic deprivation was 0.71 (95%CI 0.56-0.91, p=0.01).

CONCLUSION

This study adds evidence about the association of socioeconomic deprivation and AMI occurrence from a rural area in eastern Germany. Further research about the relationship of socioeconomic deprivation and cardiovascular health is needed from heterogeneous contexts.

Essential Polyunsaturated Fatty Acids in Blood from Patients with and without Catheter-Proven Coronary Artery Disease

Coronary artery disease (CAD) is the leading cause of death worldwide. Statins reduce morbidity and mortality of CAD. Intake of n-3 polyunsaturated fatty acid (n-3 PUFAs), particularly eicosapentaenoic acid (EPA), is associated with reduced morbidity and mortality in patients with CAD. Previous data indicate that a higher conversion of precursor fatty acids (FAs) to arachidonic acid (AA) is associated with increased CAD prevalence. Our study explored the FA composition in blood to assess n-3 PUFA levels from patients with and without CAD. We analyzed blood samples from 273 patients undergoing cardiac catheterization. Patients were stratified according to clinically relevant CAD (n = 192) and those without (n = 81). FA analysis in full blood was performed by gas chromatography. Indicating increased formation of AA from precursors, the ratio of dihomo-gamma-linolenic acid (DGLA) to AA, the delta-5 desaturase index (D5D index) was higher in CAD patients. CAD patients had significantly lower levels of omega-6 polyunsaturated FAs (n-6 PUFA) and n-3 PUFA, particularly EPA, in the blood. Thus, our study supports a role of increased EPA levels for cardioprotection.

ICD exchange in the elderly

Background

ICD therapy in elderly patients is controversially discussed, since survival benefits might be attenuated by non-arrhythmic causes of death.

Purpose

This study aimed to investigate the outcome of septua- and octogenarians after ICD generator exchange (GE).

Methods

506 patients undergoing elective GE were analysed to determine the incidence of ICD shocks and survival after GE. For further analysis, patients were divided according to age (70 – 79 or ≥80 years) and previous ICD therapy: patients that did not experience a shock and patients that received at least one shock from prior ICDs.

Results

The effect of the ICD on all-cause mortality and arrhythmic death was determined for two groups (patients with 70 – 79 and ≥80 years). Comparing septua- with octogenarians, similar left ventricular ejection fraction (35.6±11.2% vs. 32.4±8.9%) and baseline prevalence of NYHA class 3 or 4 heart failure (17.1% vs. 14.7%) was found. Older patients were more likely to die of non-arrhythmic death (22% per year vs. 8% per year, p&lt;0.001). We also investigated the necessity of ICD therapy dependent on whether ICD therapy occurred during the previous battery live. Septuagenarians and octogenarians with previous shocks had a higher incidence of further ICD therapy in the following battery life period (41% vs. 19%, p&lt;0.001, and 22% vs. 17%, p&lt;0.001).

Conclusion

Decision making for ICD generator exchange among elderly patients should be considered carefully for an individual patient during clinical practice.

Funding Acknowledgement

Type of funding sources: None.

High-density lipoprotein lipid peroxidation in association with presence of coronary artery disease and atrial fibrillation in a large cross-sectional study

Background

The function of high-density lipoprotein (HDL) cholesterol may play a more important role in the prevention of cardiovascular disease compared to the concentration of the HDL. Cardiovascular diseases such as coronary artery disease (CAD) and atrial fibrillation (AF) have been linked to impaired HDL function.

Purpose

The aim of the present study is to assess a biochemical measure of the antioxidant function of HDL and its association with presence of CAD and AF.

Methods

Patients admitted for elective cardiac catheterization were recruited in this cross-sectional study. Out of 1231 participants that were included in the analyses, 727 patients had confirmed CAD (CAD group), 369 patients had no CAD (no CAD group) and 129 persons were included as a control group. HDL function was measured in sera by determination of HDL-lipid peroxidation content (HDLox) assessed by a validated fluorometric cell-free biochemical assay and was normalized for the levels of HDL cholesterol (normalized HDLox/HDL-C ratio or nHDLox; no units). Results are expressed as median with interquartile range. Associations of nHDLox with presence of CAD and AF were assessed by univariate and multivariate analyses.

Results

Participants in the CAD group had higher levels of nHDLox (0.80, 0.61–1.03) compared to the no CAD (0.70, 0.55–0.93) and control (0.66, 0.55–1.03, no units, p&lt;0.001) group. Out of 1206 participants, 233 (19%) had AF and 973 (81%) had no AF. Patients with AF have also higher nHDLox (0.82, 0.60–10.03) compared to persons without AF (0.73, 0.58–0.98, p=0.03). In univariate analysis nHDLox was associated with CAD (p&lt;0.001). In multivariate analysis adjusted for age, gender, CAD, BMI and hypertension, nHDLox was a strong independent predictor of atrial fibrillation (p=0.015) but was not an independent predictor of CAD (p&gt;0.05)

Conclusions

Reduced antioxidant function of HDL (increased HDLox measured by a biochemical assay), a metric of HDL function, is increased in patients with atherosclerosis and manifested CAD and is also associated with the presence of atrial fibrillation independent of the presence of CAD.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Medical School of Brandenburg-MHB Fontane

Feasibility of non-invasive measurement of central blood pressure and arterial stiffness in shock

BACKGROUND

Patients in haemodynamic shock are in need for an intensive care treatment. Invasive haemodynamic monitoring is state of the art for these patients. However, evolved, non-invasive blood pressure monitoring devices offer advanced functions like the assessment of central blood pressure and arterial stiffness. We analysed the feasibility of two oscillometric blood pressure devices in patients with shock.

METHODS

We performed a monocentre prospective study, enrolling 57 patients admitted to the intensive care unit (ICU), due to septic and/or cardiogenic shock. We assessed invasive and non-invasive peripheral and central blood pressure <24 hours and 48 hours after admission on the ICU. Additional haemodynamic parameters such as pulse wave velocity (PWV), augmentation pressure and augmentation index were obtained through Mobil-o-Graph PWA (IEM) and SphygmoCor XCEL (AtCor Medical).

RESULTS

A complete haemodynamic assessment was successful in all patients (48) with the Mobil-o-Graph 24 hours PWA and in 29 patients with the SphygmoCor XCEL (P = .001), when cases of death or device malfunction were excluded. Reasons for failure were severe peripheral artery disease, haemodynamic instability, oedema and agitation. Invasive blood pressure showed a sufficient correlation with both devices; however, large differences between invasive and non-invasive techniques were recorded in Bland-Altmann analysis (P < .05 for all parameters). PWV differed between the two devices.

CONCLUSION

Non-invasive peripheral blood pressure measurement remains a rescue technique. However, non-invasive assessment of arterial stiffness and central blood pressure is possible in patients with septic or cardiogenic shock. Further studies are required to assess their clinical significance for patients in shock.

Effective treatment of electrical storm by a wearable cardioverter defibrillator in a patient with severely impaired left ventricular function after myocardial infarction: a case report

Background

The implantation of cardioverter defibrillators (ICDs) is an established therapy in the prevention of sudden cardiac death in patients with systolic dysfunction after myocardial infarction. To avoid immediate implantation of an ICD, wearable cardioverter defibrillator vests (WCD) can be used to protect patients against malignant rhythm disorders, while at the same time drug-based heart failure therapy has to be initiated. This drug therapy can improve left ventricular ejection fraction and primary prophylactic cardioverter defibrillator implantation may not be necessary. However, the recent Vest Prevention of Early Sudden Death Trial (VEST) questioned the regular use of the WCD in this setting.

Case presentation

A 47-year-old Caucasian man with severely impaired left ventricular function early after myocardial infarction was prescribed a WCD as primary prophylaxis to prevent sudden cardiac death. Seven days after the patient was supplied with a WCD, the patient suffered from an electrical storm with recurrent ventricular tachycardia (VT), which was successfully terminated 17 times by the WCD. On coronary angiography, the formerly infarct-related right coronary artery had TIMI (Thrombolysis in Myocardial Ischemia Trial) III flow, and a remaining stenosis in the left anterior descending artery (LAD) was stented, which did not stop recurrent VT. In the electrophysiology (EP) study, a focus was mapped in the left inferior ventricle, which was ablated. This stopped the VT. A second radio-frequency (RF) ablation in the same area was necessary after 14 days. Finally, a permanent cardioverter defibrillator was implanted.

Conclusion

We report the case of a patient who survived recurrent episodes of VT early after myocardial infarction by effective defibrillation with a WCD. The WCD is a useful device to bridge time until a final decision for implantation of a defibrillator.

Secondary Prevention of Potentially Life-Threatening Arrhythmia Using Implantable Cardioverter Defibrillators in Patients with Biopsy-Proven Viral Myocarditis and Preserved Ejection Fraction

BACKGROUND

Arrhythmia and sudden cardiac death (SCD) are known complications of acute viral myocarditis, regardless of ejection fraction (EF) at presentation. Whether such complications confer long-term risk is unknown, especially in those who present with preserved left ventricular (LV) function. No guidelines exist to the long-term reduction of arrhythmic death in such patients.

METHOD

In this retrospective study, we analyzed the long-term results of implantable cardioverter defibrillator (ICD) treatment in patients after an acute phase of myocarditis with life-threatening arrhythmia.

RESULTS

We identified 51 patients who had ICDs implanted following life-threatening arrhythmia presentation of confirmed acute viral myocarditis, despite preserved LVEF. Overall, 72.5% of patients had a clinical history of chest pain and viral infection with fever. Viral myocarditis was confirmed by cardiac magnetic resonance imaging (all had late enhancement) plus endomyocardial biopsies (most frequent were Epstein-Barr virus 29.4%, adenovirus 17.6%, and Coxsackie 17.6%), and 88.2% were discharged on anti-arrhythmic drugs. Overall, 12 patients (23.5%) required ICD intervention within the first 3 months, a further 7 patients (37.3% overall) between 3 and 12 months, and a further 12 patients (60.8% overall) until 58 months. During the follow-up, 3 of 51 patients (5.9%) died-deaths were due to cardiac events (n = 1), fatal infection (n = 1), and car accidents (n = 1). Of the 31 patients who had ventricular tachycardias after the acute phase of myocarditis, 11 needed radiofrequency ablation due to a high number of events or electrical storm. No baseline variables were identified that would serve as a basis for risk stratification.

CONCLUSION

Malignant arrhythmic events due to viral myocarditis are potential predictors of future SCD in patients not only with a reduced but also with a preserved EF.

Dickkopf-3 in the prediction of contrast media induced acute kidney injury

Background

Dickkopf-3 (DKK3) has recently been discovered as a urinary biomarker for the prediction of acute kidney injury (AKI) after cardiac surgery. This finding needs to be confirmed for AKI in other clinical settings. The present study investigates whether DKK3 can predict contrast-induced AKI (CI-AKI).

Methods

We performed a prospective study in 490 patients undergoing coronary angiography. Primary endpoint was an increase in serum creatinine concentration ≥ 0.3 mg/dl within 72 h after the procedure. DKK3 was assessed < 24 h before coronary angiography. Predictive accuracy was assessed by receiver operating characteristic (ROC) curves.

Results

CI-AKI was observed in 30 (6.1%) patients, of whom 27 corresponded to stage I and 3 to stage II according to the Acute Kidney Injury Network (AKIN) criteria. Subjects who developed CI-AKI had a 3.8-fold higher urinary DKK3/creatinine ratio than those without CI-AKI (7.5 pg/mg [interquartile range [IQR] 1.2–1392.0] vs. 2.0 pg/mg [IQR 0.9–174.0]; p = 0.047). ROC analysis revealed an area under the curve (AUC) of 0.61. Among subjects without clinically overt chronic kidney disease (estimated glomerular filtration rate [eGFR] > 60 ml/min, urinary albumin creatinine ratio < 30 mg/g), the DKK3/creatinine ratio was 5.4-fold higher in those with subsequent CI-AKI (7.5 pg/mg [IQR 0.9–590.1] vs. 1.38 pg/mg [IQR 0.8–51.0]; p = 0.007; AUC 0.62). Coronary angiography was associated with a 43 times increase in the urinary DKK3/creatinine ratio.

Conclusions

Urinary DKK3 is an independent predictor of CI-AKI even in the absence of overt chronic kidney disease (CKD). The study thereby expands the findings on DKK3 in the prediction of postoperative loss of kidney function to other entities of AKI.

Graphic abstract

Oxidation of HDL in patients with coronary artery disease

 

The function of high-density lipoprotein (HDL) cholesterol may play a more important role in the prevention of cardiovascular disease compared to the concentration of the HDL. The aim of the present study is to assess a novel cell-free test to quantify oxidation of HDL and its association to coronary artery disease (CAD).

We performed a prospective trial by including patients undergoing elective cardiac catheterization and healthy controls. A total of 895 subjects were included. In 483 patients CAD was confirmed (CAD group) and in 241 patients CAD was ruled-out (no CAD). Control patients (n=171) had no known CAD, had no diabetes and were not smokers. HDL function was measured in serum samples by determining its HDL-lipid peroxidation by a novel fluorometric cell-free biochemical assay. HDL lipid peroxide content (HDLox) is adjusted for the HDL cholesterol and has no units.

Patients with confirmed CAD had higher levels of HDLox (0.92±0.58, no units) compared to patients with no CAD (0.8±0.46, no units) and controls (0.78±0.41, no units, p=0.003). HDL-Cholesterol was lower in the CAD group (50.7±17.7mg/dl) compared to no CAD (58.4±17.6mg/dl) and healthy subjects (59.1±15.9mg/dl, p&lt;0.001). HDLox was a strong predictor of coronary artery disease status (odds ratio for coronary disease 1.69; 95% confidence interval [CI], 1.24 to 2.38; P=0.001).

Oxidation of HDL, a metric of HDL function, measured by a cell-free biochemical assay, is increased in patients with CAD and is a predictor of the disease.

Logistic Regression analysis

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Medical School of Brandenburg

Biomarkers in the prediction of contrast media induced nephropathy - the BITCOIN study

Background

Subjects with chronic kidney disease are at increased risk for contrast-induced acute kidney injury (CI-AKI). Risk stratification is traditionally based on glomerular filtration rate (GFR) and proteinuria. The present trial examines, whether tubular and inflammatory biomarkers are able to identify subjects at increased risk as well.

Methods

We performed a prospective study in 490 patients undergoing coronary angiography. An increase of serum creatinine concentration ≥ 0.3 mg/dl from baseline to day 2–3 was defined as primary endpoint (CI-AKI). Urinary neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), and calprotectin were assessed < 24h before coronary angiography. Prognostic accuracy was assessed by receiver operating characteristics (ROC) calculations.

Results

30 (6.1%) patients suffered from CI-AKI (27 AKIN stage I, 3 AKIN stage II, 0 AKIN stage III). Those subjects who developed CI-AKI had 3.1 fold higher baseline urinary NGAL/creatinine ratios than those without CI-AKI (60.8 [IQR 18.7–93.1] μg/mg vs. 19.9 [IQR 12.3–38.9] μg/mg, p = 0.001). In those subjects without clinically overt CKD (eGFR > 60 ml/min, urinary albumin creatinine ratio <30 mg/g), the NGAL/creatinine ratio was 2.6 higher in CI-AKI vs. no CI-AKI (47.8 [IQR 11.8–75.3] vs. 18.6 [IQR 11.7–36.3] μg/mg). No significant differences were obtained for KIM-1 and calprotectin (p>0.05 each). ROC analyses revealed an area under the curve (AUC) of 0.68 (95% CI 0.60–0.81) for NGAL/creatinine. An NGAL/creatinine ratio < 56.4 μg/mg has a negative predictive value of 96.5%.

Conclusions

The present study is the largest investigation on the use of urinary biomarkers for CI-AKI risk stratification so far. It shows that NGAL provides prognostic information beyond the glomerular biomarkers eGFR and proteinuria.

Hemodynamic Effects of a Multidisciplinary Geriatric Rehabilitation Program

Background

Geriatric rehabilitation programs primarily aim at an increase of mobility and functional autonomy of the elderly. The cardiovascular effects of these programs, however, remain elusive. Since regular physical exercise is associated with numerous beneficial cardiovascular effects including a reduction of blood pressure (BP), the present prospective study investigates the hemodynamic effects of a representative standardized rehabilitation program.

Methods

A total of 74 subjects who were hospitalized in a German university hospital for geriatric rehabilitation were enrolled in the study. Peripheral BP, central aortic BP, 24h-ambulatory BP, heart rate and pulse wave velocity as a measure of arterial stiffness were assessed at admission and before discharge from the hospital. The program contained 4-5 sessions of physical activity of individualized intensity per week (≥30 min/session, eg, walking, cycling, stair rising).

Results

The mean age of the study population was 82.4±6.9 years; all patients suffered from arterial hypertension (stage 2-3) with a median number of three antihypertensive drugs. The most frequent cause for admission was injurious falls. The mean duration of the rehabilitation program was 17 days and comprised at least 20 physical activity sessions including occupational therapy. The program led to a significant improvement of mobility (Timed Up & Go 29.5±18.5 vs 19.1 ±9.3 s, p<0.001) and Barthel index of activities of daily living score (46.6±19.1 vs 69.8±16.5, p<0.001). Peripheral systolic BP decreased from 135.4±19.0 mmHg at baseline to 129.0±18.4 mmHg at follow-up (p=0.03), whereas peripheral diastolic BP, central aortic BP, 24h-ambulatory BP, heart rate and pulse wave velocity as a measure of arterial stiffness were not significantly altered (p>0.05 each).

Conclusion

The present representative standardized geriatric rehabilitation program was able to improve mobility, which showed a mild effect on systolic BP but did not affect 24h-ambulatory BP.

Intensive blood pressure control is associated with improved patient and graft survival after renal transplantation

Based on data of the SPRINT trial, American hypertension guidelines recently reduced the blood pressure goal from 140/90 mmHg to 130/80 mmHg for subjects with chronic kidney disease (CKD), whereas European guidelines recommend a systolic blood pressure (SBP) of 130-139 mmHg. The present analysis investigates whether a SBP < 130 mmHg is associated with an additional benefit in renal transplant recipients. We performed a retrospective analysis of 815 renal transplant recipients who were stratified according to mean office SBP values < 130 mmHg, 130-139 mmHg or ≥140 mmHg. Patient and graft survival was defined as composite endpoint, follow-up was limited to 120 months. Mean SBP of the follow-up was significantly associated with the composite endpoint (n = 218) with better survival for a SBP < 130 mmHg and 130-139 mmHg compared to ≥140 mmHg (p < 0.001). The differences in the combined endpoint remained significant in Cox regression analysis adjusted for age, gender and eGFR (p = 0.007, HR = 0.58, 95%CI = 0.41-0.53), but not for graft survival alone. Renal transplant recipients with SBP < 130 mmHg had a lower mortality than those with the conservative blood pressure goal <140 mmHg. These data suggest that the new AHA BP targets are safe for renal transplant recipients and - with all limitations of a retrospective analysis - might even be associated with improved outcome.

The impact of aerobic and isometric exercise on different measures of dysfunctional high-density lipoprotein in patients with hypertension

BACKGROUND

Exercise training increases high-density lipoprotein (HDL) cholesterol, but its effect on HDL function is unclear. In hypertensives, exercise improves endothelial dysfunction, which is related to HDL function. In the present study, we assess for the first time the effects of different exercise modalities on two cell-free assays of HDL function.

DESIGN

The study was conducted as a prospective randomized controlled trial in 75 hypertensive patients.

METHODS

Patients were randomized in three groups: (a) handgrip isometric training five times weekly; (b) placebo-handgrip; and (c) aerobic exercise training at least three times per week. HDL function was assessed in serum samples at baseline and after 12 weeks of training by two independent assays that determine the proinflammatory phenotype (haptoglobin content) of a specific amount of HDL (Haptoglobin-HDL [HPHDL]) and oxidized HDL (HDLox) as a measure of reduced antioxidant function of HDL. HDL function measures were normalized by the measures of a pooled control of sera from healthy participants and by HDL-C levels (normalized ratio, no units).

RESULTS

Aerobic exercise led to significant reduction of the HDLox from 0.99 ± 0.27 to 0.90 ± 0.29 (no units, p = 0.03). The HPHDL did not change in any training group. Changes of HDLox correlated with reduction of the systolic blood pressure only after aerobic exercise (R = 0.64, p = 0.03).

CONCLUSIONS

Aerobic but not isometric exercise improves the antioxidant function of HDL in patients with hypertension. This improvement correlates positively with reductions of blood pressure.

Recanalization of bilateral axillaris/brachialis artery occlusion in a patient with Takayashu arteritis: First case report on using a novel drug-coated nitinol "chocolate" balloon catheter

When fibrosis develops in Takayasu arteritis (TA), endovascular treatment may become necessary. A 63-year-old woman with TA underwent PTA with a nitinol-structured (chocolate-like) drug-coated balloon (C-DEB PTA). She remained in remission for >1 year. The case may foster research into the use of C-DEB PTA in TA.

Effects of late cyclosporine withdrawal on renal graft function and survival

OBJECTIVE

Attempts to discontinue calcineurin inhibitors (CNIs) early after renal transplantation without conversion to an alternative immunosuppressive have failed due to high rates of acute rejection. Data on "late" CNI withdrawal are lacking so far.

DESIGN AND METHOD

We carried out a matched case-control study on the effects of CNI withdrawal on graft loss and mortality in 90 patients (1500 screened) with advanced graft dysfunction (serum creatinine > 3.5 mg/dl) and a cyclosporine-based triple immunosuppressive regimen at the Charité University Hospital, Berlin.

RESULTS

Cyclosporine was withdrawn at a mean of 54.0 ± 32.8 months post-transplant in 45 subjects. Whereas estimated glomerular filtration rate (eGFR) did not significantly differ between the groups at this time (12.4 ± 2.7 vs. 14.7 ± 8.9 in the control group, p = 0.08), it was significantly higher in subjects undergoing withdrawal after 120 months (Δ 4.1 ml/min; p < 0.001). In a Cox regression analysis adjusted for age, gender and eGFR, patients with CNI withdrawal showed better survival rates for the combined endpoint death/graft loss (hazard ratio, HR [95% confidence interval]: 0.19 [0.12-0.33], p = 0.001) compared to matched controls. The survival benefit was significant for the endpoints death (p = 0.01) and graft loss (p = 0.001).

CONCLUSIONS

CNI withdrawal was associated with improved survival rates in patients with advanced graft dysfunction in this retrospective analysis.

The impact of blood pressure variability and pulse pressure on graft survival and mortality after kidney transplantation

BACKGROUND

Blood pressure variability and pulse pressure are strong and independent predictors of cardiovascular morbidity and mortality in the general population. So far, there are no data on the impact of blood pressure variability on mortality and graft survival after renal transplantation.

METHODS

We performed a retrospective analysis of 877 patients who underwent kidney transplantation between 1997 and 2011 in two transplant centers in Germany (Berlin and Bochum) with a follow-up of 12-266 months. Visit-to-visit blood pressure variability over the first 12 months after transplantation (3 visits) and during the first 120 months after transplantation (7 visits) was calculated as the coefficient of variation (CV = standard deviation (SD)/mean blood pressure). Patient and graft survival was defined as composite endpoint.

RESULTS

Cumulative survival was significantly higher for those patients with lower systolic blood pressure and pulse pressure within both the first 12 months and the 120 months posttransplant. After adjustment of data for gender, age, body mass index, and coronary artery disease, the cumulative incidence of the combined endpoint did not significantly differ between patients with lower vs higher CV (12 months CV hazard ratio (HR) (95% CI) = 0.90 (0.66-1.23), P = 0.51; 120 months CV HR (95% CI) = 0.92 (0.67-1.26), P = 0.60). A lower systolic blood pressure remained highly predictive for better survival in adjusted analyses.

CONCLUSION

Visit-to-visit blood pressure variability is not associated with mortality or graft loss after kidney transplantation in this retrospective analysis. In analogy to the general population, however, there is an inverse relationship of survival and pulse pressure as a marker of arterial stiffness.

The Effect of Microgravity on Central Aortic Blood Pressure

BACKGROUND

Blood pressure has been traditionally measured at peripheral arteries. In the past decade, evidence has grown that central aortic blood pressure may be a more powerful predictor for cardiovascular events, but data on its regulation are rare. The present work examines the impact of microgravity on central blood pressure for the first time.

METHODS

We performed 7 parabolic flights with 22 seconds of weightlessness in each parabola. Hemodynamic parameters including central systolic blood pressure were measured noninvasively in a free-floating position in 20 healthy subjects (19-43 years of age).

RESULTS

Arterial elasticity at rest was normal in all participants (augmentation index 14% (interquartile range (IQR) 10-22), pulse wave velocity 5.2 m/s (IQR 5.0-5.4)). Transition of 1g to 0g led to a significant increase of central systolic blood pressure from 124 (IQR 118-133) to 127 (IQR 119-133) mm Hg (P = 0.017). Cardiac index augmented significantly from 2.5 (IQR 2.2-2.8) to 2.7 (IQR 2.3-3.0) l/min/m2 (P < 0.001), while peripheral vascular resistance showed a decrease from 1.30 (IQR 1.14-1.48) to 1.25 (IQR 1.15-1.40) s × mm Hg/ml (P = 0.037). Peripheral systolic blood pressure did not change significantly (P > 0.05).

CONCLUSION

Whereas there is a multitude of studies on the effects of microgravity on peripheral blood pressure, this study provides first data on central aortic blood pressure. An acute loss of gravity leads to a central blood volume shift with an augmentation of cardiac output. In healthy subjects with normal arterial stiffness, the compensatory decrease of peripheral resistance does not outweigh this effect resulting in an increase of central blood pressure.

Description of a novel RyR2 mutation in a juvenile patient with symptomatic catecholaminergic polymorphic ventricular tachycardia in sleep and during exercise: a case report

Background

Catecholaminergic polymorphic ventricular tachycardia is an inherited disease presenting with arrhythmic events during physical exercise or emotional stress. If untreated, catecholaminergic polymorphic ventricular tachycardia is a highly lethal condition: About 80% of affected individuals experience recurrent syncope, and 30% experience cardiac arrest. Catecholaminergic polymorphic ventricular tachycardia is caused by mutations in genes encoding ryanodine receptor type 2 (RyR2) and cardiac calsequestrin (CASQ2). In cases of sympathoadrenergic activation, both mutations result in a spontaneous Ca²⁺ release in cardiac cells, facilitating ventricular arrhythmias.

Case presentation

We present a case of a 17-year-old Caucasian boy who survived sudden cardiac death caused by ventricular fibrillation while performing running exercise in a fitness center. The diagnostic workup included blood tests, coronary angiography, electrophysiological testing, and cardiac magnetic resonance imaging, but all results were normal. Because the patient’s medical history included recurrent syncope during physical and emotional stress, we strongly suspected catecholaminergic polymorphic ventricular tachycardia as the underlying disease. Genetic screening was performed and confirmed the diagnosis, revealing a new heterozygous point mutation in the gene for RyR2, c.12520T>A (p.F4174 l, exon 90, RyR2 gene). The patient was discharged from our hospital after undergoing implantation of an implantable cardioverter defibrillator for secondary prevention. Shortly after implantation, the implantable cardioverter defibrillator terminated a sustaining ventricular tachycardia episode by antitachycardic pacing. This episode occurred early in the morning while the patient was asleep.

Conclusions

We present a case of catecholaminergic polymorphic ventricular tachycardia associated with a novel single point mutation in the RyR2 gene, which, to the best of our knowledge, has not been described in the literature so far. Our patient experienced arrhythmic events under both resting conditions and physical activity, an uncommon finding in patients with catecholaminergic polymorphic ventricular tachycardia. This novel mutation may cause arrhythmias independent of sympathoadrenergic stimulation, but further evidence is needed to prove causality.

Nitroglycerin application and coronary arteriogenesis

BACKGROUND

In the presence of a coronary occlusion, pre-existing small collateral vessels (arterioles) develop into much larger arteries (biological bypasses) that have the potential to allow a certain level of perfusion distal to the blockage. Termed arteriogenesis, this phenomenon proceeds via a complex combination of events, with nitric oxide (NO) playing an essential role. The aim of this study was to investigate the effects of supplemental administration of NO donors, i.e., short-acting nitroglycerin (NTG) or slow-release pelleted isosorbide dinitrate (ISDN), on collateral development in a repetitive coronary artery occlusion model in rats.

METHODS

Coronary collateral growth was induced via a repetitive occlusion protocol (ROP) of the left anterior descending coronary artery (LAD) in rats. The primary endpoints were the histological evaluation of rat heart infarct size and ST-segment elevation (ECG-analysis) upon final permanent occlusion of the LAD (experimentally induced myocardial infarction). The effects of NTG or ISDN were also evaluated by administration during 5 days of ROP. We additionally investigated whether concomitant application of NTG can compensate for the anti-arteriogenic effect of acetylsalicylic acid (ASA).

RESULTS

After 5 days of ROP, the mean infarct size and degree of ST-elevation were only slightly lower than those of the SHAM group; however, after 10 days of the protocol, the ROP group displayed significantly less severe infarct damage, indicating enhanced arteriogenesis. Intermittent NTG application greatly decreased the ST-elevation and infarct size. The ISDN also had a positive effect on arteriogenesis, but not to the same extent as the NTG. Administration of ASA increased the infarct severity; however, concomitant dosing with NTG somewhat attenuated this effect.

CONCLUSION

Intermittent treatment with the short-acting NTG decreased the size of an experimentally induced myocardial infarct by promoting coronary collateral development. These new insights are of great relevance for future clinical strategies for the treatment of occlusive vascular diseases.

Prognostic Value of Urinary Calprotectin, NGAL and KIM-1 in Chronic Kidney Disease

BACKGROUND/AIMS

Urinary biomarkers like neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) do not only allow an early diagnosis of acute kidney injury, but also provide prognostic information in this setting. The present prospective study investigates, whether the urinary biomarkers NGAL, KIM-1 and calprotectin have prognostic information in chronic kidney disease (CKD) as well.

METHODS

Urinary calprotectin, NGAL and KIM-1 concentrations were assessed in a study population of 143 patients with stable CKD comprising diabetic and hypertensive nephropathy, glomerulonephritis/vasculitis, and autosomal dominant polycystic kidney disease. An eGFR fluctuation > 5ml/min/1.73m2 in the past 12 months was defined as an exclusion criterion in order to exclude cases with acute on chronic kidney injury. Renal function was monitored for a median follow-up of 37 months.

RESULTS

In the overall study population, all the three biomarkers failed to predict DeGFR and DACR from baseline to follow-up in linear regression analysis adjusted for age, gender, and baseline eGFR. Contrarily, baseline ACR was significantly associated with DeGFR (p< 0.001). In the subgroup of patients with vasculitis and glomerulonephritis, all the three biomarkers were significantly associated with DeGFR, with calprotectin having the highest regression coefficient.

CONCLUSION

In contrast to the traditional biomarker "albuminuria", neither the inflammatory biomarker calprotectin, nor the tubular biomarkers NGAL and KIM-1, provide robust prognostic information on the loss or renal function in a heterogeneous CKD population. All of them, however, are candidate prognostic biomarkers in primarily inflammatory renal diseases.

Size matters: An observational study investigating estimated height as a reference size for calculating tidal volumes if low tidal volume ventilation is required

Purpose

Acute lung injury is a life threatening condition often requiring mechanical ventilation. Lung-protective ventilation with tidal volumes of 6 mL/kg predicted body weight (PBW, calculated on the basis of a patient’s sex and height), is part of current recommended ventilation strategy. Hence, an exact height is necessary to provide optimal mechanical ventilation. However, it is a common practice to visually estimate the body height of mechanically ventilated patients and use these estimates as a reference size for ventilator settings. We aimed to determine if the common practice of estimating visual height to define tidal volume reduces the possibility of receiving lung-protective ventilation.

Methods

In this prospective observational study, 28 mechanically ventilated patients had their heights visually estimated by 20 nurses and 20 physicians. All medical professionals calculated the PBW and a corresponding tidal volume with 6 ml/kg/PBW on the basis of their visual estimation. The patients’ true heights were measured and the true PBW with a corresponding tidal volume was calculated. Finally, estimates and measurements were compared.

Results

1033 estimations were undertaken by 153 medical professionals. The majority of the estimates were imprecise and resulting data comprised taller body heights, higher PBW and higher tidal volumes (all p≤0.01). When estimates of patients´ heights are used as a reference for tidal-volume definition, patients are exposed to mean tidal volumes of 6.5 ± 0.4 ml/kg/PBW. 526 estimation-based tidal volumes (51.1%) did not provide lung-protective ventilation. Shorter subjects (<175cm) were a specific risk group with an increased risk of not receiving lung protective ventilation (OR 6.6; 95%CI 1.2–35.4; p = 0.02), while taller subjects had a smaller risk of being exposed to inadequately high tidal volumes (OR 0.15; 95%CI 0.02–0.8; p = 0.02). Furthermore, we found an increased risk of overestimating if the assessor was a female (OR 1.74; 95%CI 1.14–2.65; p = 0.01).

Conclusion

The common practice of visually estimating body height and using these estimates for ventilator settings is imprecise and potentially harmful because it reduces the chance of receiving lung-protective ventilation. Avoiding this practice increases the patient safety. Instead, height should be measured as a standard procedure.

Serum Uric Acid and Arterial Function After Renal Transplantation

BACKGROUND Hyperuricemia is associated with an increased risk of cardiovascular disease and chronic allograft nephropathy after renal transplantation. It has recently been demonstrated that treatment of asymptomatic hyperuricemia is associated with improved patient and graft survival; although, the underlying mechanisms remain elusive. The present study investigated the association of serum uric acid (SUA) and systemic arterial function after renal transplantation. MATERIAL AND METHODS In a cross-sectional study, arterial function was analyzed in 54 renal transplant recipients by means of pulse wave analysis. Different measurement techniques were combined providing data on pulse wave velocity, augmentation index, small and large artery elasticity, and total peripheral vascular resistance. RESULTS The prevalence of hyperuricemia was 87.0%, and 33.3% of renal transplant recipients received SUA lowering medication. The median SUA concentration was 7.4 mg/dL. There was no significant difference in all the aforementioned parameters in patients with a SUA <7.4 versus >7.4 mg/dL (p>0.05 each) and no significant differences between hyperuricemic patients with versus without SUA lowering medication. Linear regression analysis between SUA and both pulse wave velocity and augmentation index showed no significant association (p>0.05 each). This finding remained consistent after adjustment of data for age, time on dialysis, time since transplantation, and systolic blood (partial correlation analysis, p>0.05). CONCLUSIONS Neither the concentration of SUA nor the pharmacological treatment of hyperuricemia had measurable effects on arterial stiffness. Thus, the beneficial effects of SUA lowering treatment on patient and graft survival cannot be explained by direct effects on arterial function in the study population.

Urinary biomarkers for the differentiation of prerenal and intrinsic pediatric acute kidney injury

BACKGROUND

Urinary calprotectin and neutrophil gelatinase-associated lipocalin (NGAL) have recently been identified as promising biomarkers for the differentiation of prerenal and intrinsic acute kidney injury (AKI) in adults. In the study reported here we examined the diagnostic accuracy of calprotectin, NGAL, and kidney injury molecule 1 (KIM-1) in pediatric patients.

METHODS

Urinary calprotectin, NGAL, and KIM-1 concentrations were assessed in a study population of 139 pediatric subjects including 39 patients with intrinsic AKI, 14 with prerenal AKI, and 86 non-AKI subjects.

RESULTS

Median urinary calprotectin and NGAL concentrations were higher in patients with intrinsic AKI than in those with prerenal AKI (calprotectin by 22-fold, NGAL by 9-fold). Receiver operating characteristic (ROC) curve analyses for the differentiation of intrinsic and prerenal AKI resulted in an area under the curve (AUC) of 0.90 [95 % confidence interval (CI) 0.81-0.98] for calprotectin and 0.73 (95 % CI 0.58-0.87) for NGAL. Median urinary KIM-1 concentrations were not significantly different between patients with prerenal AKI and those with intrinsic disease (P = 0.98; AUC 0.50, 95 % CI, 0.35-0.65). The AUC for the fractional excretion of sodium (FE_Na) and proteinuria was 0.78 (95 % CI 0.63-0.92) and 0.77 (CI 0.65-0.90), respectively.

CONCLUSIONS

Urinary calprotectin outperforms NGAL, KIM-1, FE_Na, and proteinuria as a biomarker for the differentiation of prerenal and intrinsic AKI in pediatric patients with a high diagnostic accuracy.

Effects of Treatment of Asymptomatic Hyperuricemia on Graft Survival and Mortality in Kidney Transplant Recipients

BACKGROUND Hyperuricemia is very common after renal transplantation. It is associated with an increased risk of cardiovascular events and graft loss. To date, however, treatment is only recommended in symptomatic disease. MATERIAL AND METHODS We included 503 adult patients who underwent kidney transplantation at the Charité-Universitätsmedizin Berlin in this retrospective study. Patients were followed up for up to 120 months. All-cause mortality, graft survival, changes in level of serum uric acid (SUA), and estimated glomerular filtration rate (eGFR) were analyzed. RESULTS At 12 months post-transplantation, 225 patients had a serum uric acid (SUA) level >7 mg/dl: 52 patients were treated with allopurinol, 37 with benzbromarone, and 136 patients received no medication for hyperuricemia (control). At 12 months, eGFR did not differ between groups (p=0.15) but treated patients had higher SUA levels (p<0.001) compared to the control group. SUA-lowering treatment was associated with a lower risk of all-cause mortality (p=0.013) and graft loss (p=0.014) compared to controls. At 120 months, patients in the treatment group had lower SUA levels (p=0.001) and higher eGFR (p<0.001) compared to the control group. CONCLUSIONS Treatment of asymptomatic hyperuricemia was associated with a substantial benefit in patient and graft survival.

Dynamics of Urinary Calprotectin after Renal Ischaemia

Background: Urinary calprotectin has been identified as a promising biomarker for acute kidney injury. To date, however, the time-dependent changes of this parameter during acute kidney injury remain elusive. The aim of the present work was to define the time-course of urinary calprotectin secretion after ischaemia/reperfusion-induced kidney injury in comparison to neutrophil gelatinase—associated lipocalin, thereby monitoring the extent of tubular damage in nephron sparing surgery for kidney tumours. Methods: The study population consisted of 42 patients. Thirty-two patients underwent either open or endoscopic nephron sparing surgery for kidney tumours. During the surgery, the renal arterial pedicle was clamped with a median ischaemic time of 13 minutes (interquartile range, 4.5–20.3 minutes) in 26 patients. Ten retro-peritoneoscopic living donor nephrectomy patients and 6 nephron sparing surgery patients in whom the renal artery was not clamped served as controls. Urinary calprotectin and neutrophil gelatinase—associated lipocalin concentrations were repeatedly measured by enzyme-linked immunosorbent assay and assessed according to renal function parameters. Results: Urinary concentrations of calprotectin and neutrophil gelatinase—associated lipocalin increased significantly after ischaemia/reperfusion injury, whereas concentrations remained unchanged after nephron sparing surgery without ischaemia/reperfusion injury and after kidney donation. Calprotectin and neutrophil gelatinase—associated lipocalin levels were significantly increased 2 and 8 hours, respectively, post-ischaemia. Both proteins reached maximal concentrations after 48 hours, followed by a subsequent persistent decrease. Maximal neutrophil gelatinase—associated lipocalin and calprotectin concentrations were 9-fold and 69-fold higher than their respective baseline values. The glomerular filtration rate was only transiently impaired at the first post-operative day after ischaemia/reperfusion injury (p = 0.049). Conclusion: Calprotectin and neutrophil gelatinase—associated lipocalin can be used to monitor clinical and sub-clinical tubular damage after nephron sparing surgery for kidney tumours. Urinary calprotectin concentrations start rising within 2 hours after ischaemia/reperfusion-induced kidney injury.

[How do Turkish immigrants evaluate cultural sensitivity in a German tertiary hospital?]

BACKGROUND

Culturally adequate medical care is a goal in Germany, but quantitative data concerning inpatients is lacking.

METHODS

Inpatients of a German tertiary hospital: Turkish migrants (T) and Germans (G) were interviewed in their respective native language.

RESULTS

121 T and 121 G were interviewed. 97.5% of T were Muslims, 82.6% of G were Christians. 88.5% of T judged religion as "important" or "very important" (G: 35.8%). 50.8% of T saw their opportunity to pray in the hospital as "bad" or "very bad" (G: 0.9%). Keeping to Islamic dietary rules in the hospital was "difficult" or "very difficult" for 90% of T. For 79.0% of female T care by a same-sex staff was "important" or "very important" (female G: 36.3%, male T: 40.0%, male G: 7.7%). The presence of a same-sex person during examinations or treatments was "much" or "very much" appreciated by 69.7% of female T, if same-sex care was impossible (female G: 25.4%, male T: 28.9%, male G: 6.1%). A retrospective analysis revealed that 5.8% of all 8988 hospital admissions during the period of study recruitment were Turkish migrants.

CONCLUSION

To meet the needs of Turkish migrants German hospitals should improve the opportunity for Muslims to pray. Additionally, the cooperation with local imams should be sought. Precise descriptions of food ingredients or an adapted menu could help T to deal with Muslim dietary commandments. A culturally sensitive hospital should take into account that female as well as male T prefer to be cared of by same-sex physicians and nurses.

Urinary calprotectin and posttransplant renal allograft injury

Objective

Current methods do not predict the acute renal allograft injury immediately after kidney transplantation. We evaluated the diagnostic performance of urinary calprotectin for predicting immediate posttransplant allograft injury.

Methods

In a multicenter, prospective-cohort study of 144 incipient renal transplant recipients, we postoperatively measured urinary calprotectin using an enzyme-linked immunosorbent assay and estimated glomerular filtration rate (eGFR) after 4 weeks, 6 months, and 12 months.

Results

We observed a significant inverse association of urinary calprotectin concentrations and eGFR 4 weeks after transplantation (Spearman r = −0.33; P<0.001). Compared to the lowest quartile, patients in the highest quartile of urinary calprotectin had an increased risk for an eGFR less than 30 mL/min/1.73 m² four weeks after transplantation (relative risk, 4.3; P<0.001; sensitivity, 0.92; 95% CI, 0.77 to 0.98; specificity, 0.48; 95% CI, 0.31 to 0.66). Higher urinary calprotectin concentrations predicted impaired kidney function 4 weeks after transplantation, as well as 6 months and 12 months after transplantation. When data were analyzed using the urinary calprotectin/creatinine-ratio similar results were obtained. Urinary calprotectin was superior to current use of absolute change of plasma creatinine to predict allograft function 12 months after transplantation. Urinary calprotectin predicted an increased risk both in transplants from living and deceased donors. Multivariate linear regression showed that higher urinary calprotectin concentrations and older donor age predicted lower eGFR four weeks, 6 months, and 12 months after transplantation.

Conclusions

Urinary calprotectin is an early, noninvasive predictor of immediate renal allograft injury after kidney transplantation.

Sonographic assessment of spleen size in Turkish migrants with Familial Mediterranean fever in Germany

OBJECTIVES

Familial Mediterranean fever (FMF) can be associated with splenomegaly. Prospective quantitative data are lacking. We performed a sonographic assessment of spleen size in patients with FMF and healthy control participants to assess its diagnostic value.

METHODS

Patients with FMF according to the criteria of Livneh et al (Arthritis Rheum 1997; 40:1879-1885) who were in an asymptomatic interval and control participants were prospectively included in this study in Germany and underwent sonographic measurement of the spleen as well as a structured interview and a physical examination. Patients and controls were Turkish migrants.

RESULTS

Thirty-six patients and 27 controls were included. Patients and controls did not differ significantly in age (mean ± SD, 34.8 ± 9.7 versus 33.3 ± 10.0 years, respectively; P = .56), sex, height, weight, or body mass index (26.7 ± 4.7 versus 26.1 ± 4.3 kg/m(2); P = .63). Spleen size was greater in patients than controls in width (4.3 ± 1.0 versus 3.7 ± 0.7 cm; P = .008) and also length (12.1 ± 1.9 versus 10.5 ± 1.4 cm; P = .001). Twenty-six of 36 patients (72.2%) had a history of appendectomy compared to 3 of 27 controls (11.1%; P < .001). The combination of an enlarged spleen (length >11 cm and/or width >4 cm) gave specificity of 100% (95% confidence interval, 87%-100%) and a positive predictive value of 100% (95% confidence interval, 78%-100%) for the diagnosis of FMF in our study.

CONCLUSIONS

Spleen size as evaluated by sonography is larger in patients with FMF compared to healthy controls. Most patients with FMF included in this study had undergone appendectomy. Familial Mediterranean fever should be considered as a differential diagnosis in Turkish migrants in Germany if the spleen is enlarged and a history of appendectomy is reported.