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Development of an arterial pseudoaneurysm is a common complication following cardiac catheterization. We analyzed data from 6,300 patients who received left heart catheterization at our institution. One day after the procedure, approximately 10% of the patients were examined with duplex sonography. In 204 patients (3.0%), a pseudoaneurysm of the femoral artery was diagnosed. All patients underwent compression therapy. Thereby, 159 of the pseudoaneurysms could be treated successfully. The remaining 45 pseudoaneurysms had a maximal diameter of more than 1.5 cm. Forty-two patients underwent ultrasound and biopsy-line-guided thrombin injection without complications. This strategy resulted in a successful occlusion in 41 cases. Pseudoaneurysms smaller than 2 cm can be treated with compression therapy. Larger pseudoaneurysms can be occluded by thrombin injection using ultrasound guidance. Patients with a pseudoaneurysm with a wide 'neck' should be treated surgically, because the risk of an arterial occlusion following thrombin injection cannot be excluded. [ABSTRACT FROM AUTHOR]

Abstract Background Whole-body magnetic resonance angiography (WB-MRA) has shown its potential for the non-invasive assessment of nearly the entire arterial vasculature within one examination. Since the presence of extra-cardiac atherosclerosis is associated with an increased risk of coronary events, our goal was to establish the relationship between WB-MRA findings, including a systemic atherosclerosis score index, and the presence of significant coronary artery disease (CAD). Methods WB-MRA was performed on a 1.5T scanner in 50 patients scheduled to undergo elective cardiac catheterization for suspected CAD. In each patient, 40 extra-cardiac vessel segments were evaluated and assigned scores according to their luminal narrowing. The atherosclerosis score index (ASI) was generated as the ratio of summed scores to analyzable segments. Results ASI was higher in patients with significant (> 50% stenosis) CAD (n = 27) vs. patients without CAD (n = 22; 1.56 vs. 1.28, p = 0.004). ASI correlated with PROCAM (R = 0.57, p < 0.001) and Framingham (R = 0.36, p = 0.01) risk scores as estimates of the 10-year risk of coronary events. A ROC derived ASI of > 1.54 predicted significant CAD with a sensitivity of 59%, specificity of 86% and a positive predictive value of 84%. Logistic regression revealed ASI > 1.54 as the strongest independent predictor for CAD with a 11-fold increase in likelihood to suffer from significant coronary disease. On the contrary, while 15/27 (55%) of patients with CAD exhibited at least one extra-cardiac stenosis > 50%, only 3/22 (14%) of those patients without CAD did (p = 0.003). The likelihood for an extra-cardiac stenosis when CAD is present differed between vascular territories and ranged from 15% for a carotid stenosis to 44% for a stenosis in the lower extremities. Conclusion This study provides important new evidence for the close association of extra-cardiac and coronary atherosclerosis. The novel findings that a WB-MRA derived systemic atherosclerosis score index is not only associated with established cardiovascular risk scores but is also predictive of significant CAD suggest its potential prognostic implications and underline the importance to screen for coronary disease in patients with extra-cardiac manifestations of atherosclerosis.

Abstract Background Mutations in MYBPC3 encoding myosin binding protein C belong to the most frequent causes of hypertrophic cardiomyopathy (HCM) and may also lead to dilated cardiomyopathy (DCM). MYBPC3 mutations initially were considered to cause a benign form of HCM. The aim of this study was to examine the clinical outcome of patients and their relatives with 18 different MYBPC3 mutations. Methods 87 patients with HCM and 71 patients with DCM were screened for MYBPC3 mutations by denaturing gradient gel electrophoresis and sequencing. Close relatives of mutation carriers were genotyped for the respective mutation. Relatives with mutation were then evaluated by echocardiography and magnetic resonance imaging. A detailed family history regarding adverse clinical events was recorded. Results In 16 HCM (18.4%) and two DCM (2.8%) index patients a mutation was detected. Seven mutations were novel. Mutation carriers exhibited no additional mutations in genes MYH7, TNNT2, TNNI3, ACTC and TPM1. Including relatives of twelve families, a total number of 42 mutation carriers was identified of which eleven (26.2%) had at least one adverse event. Considering the twelve families and six single patients with mutations, 45 individuals with cardiomyopathy and nine with borderline phenotype were identified. Among the 45 patients, 23 (51.1%) suffered from an adverse event. In eleven patients of seven families an unexplained sudden death was reported at the age between 13 and 67 years. Stroke or a transient ischemic attack occurred in six patients of five families. At least one adverse event occurred in eleven of twelve families. Conclusion MYBPC3 mutations can be associated with cardiac events such as progressive heart failure, stroke and sudden death even at younger age. Therefore, patients with MYBPC3 mutations require thorough clinical risk assessment.

Background: Ubiquitous deletion of thioredoxin reductase 2 (Txnrd2) in mice is embryonically lethal and associated with abnormal heart development, while constitutive, heart-specific Txnrd2 inactivation leads to dilated cardiomyopathy and perinatal death. The significance of Txnrd2 in aging cardiomyocytes, however, has not yet been examined., Methods and Results: The tamoxifen-inducible heart-specific αMHC-MerCreMer transgene was used to inactivate loxP-flanked Txnrd2 alleles in adult mice. Hearts and isolated mitochondria from aged knockout mice were morphologically and functionally analyzed. Echocardiography revealed a significant increase in left ventricular end-systolic diameters in knockouts. Fractional shortening and ejection fraction were decreased compared with controls. Ultrastructural analysis of cardiomyocytes of aged mice showed mitochondrial degeneration and accumulation of autophagic bodies. A dysregulated autophagic activity was supported by higher levels of lysosome-associated membrane protein 1 (LAMP1), microtubule-associated protein 1A/1B-light chain 3-I (LC3-I), and p62 in knockout hearts. Isolated Txnrd2-deficient mitochondria used less oxygen and tended to produce more reactive oxygen species. Chronic hypoxia inducible factor 1, α subunit stabilization and altered transcriptional and metabolic signatures indicated that energy metabolism is deregulated., Conclusions: These results imply a novel role of Txnrd2 in sustaining heart function during aging and suggest that Txnrd2 may be a modifier of heart failure., (© 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Background: Type I Bartter syndrome is a recessive human nephropathy caused by loss-of-function mutations in the SLC12A1 gene coding for the Na+-K+-2Cl- cotransporter NKCC2. We recently established the mutant mouse line Slc12a1I299F exhibiting kidney defects highly similar to the late-onset manifestation of this hereditary human disease. Besides the kidney defects, low blood pressure and osteopenia were revealed in the homozygous mutant mice which were also described in humans. Beside its strong expression in the kidney, NKCC2 has been also shown to be expressed in other tissues in rodents i.e. the gastrointestinal tract, pancreatic beta cells, and specific compartments of the ear, nasal tissue and eye., Results: To examine if, besides kidney defects, further organ systems and/or metabolic pathways are affected by the Slc12a1I299F mutation as primary or secondary effects, we describe a standardized, systemic phenotypic analysis of the mutant mouse line Slc12a1I299F in the German Mouse Clinic. Slc12a1I299F homozygous mutant mice and Slc12a1I299F heterozygous mutant littermates as controls were tested at the age of 4-6 months. Beside the already published changes in blood pressure and bone metabolism, a significantly lower body weight and fat content were found as new phenotypes for Slc12a1I299F homozygous mutant mice. Small additional effects included a mild erythropenic anemia in homozygous mutant males as well as a slight hyperalgesia in homozygous mutant females. For other functions, such as immunology, lung function and neurology, no distinct alterations were observed., Conclusions: In this systemic analysis no clear primary effects of the Slc12a1I299F mutation appeared for the organs other than the kidneys where Slc12a1 expression has been described. On the other hand, long-term effects additional and/or secondary to the kidney lesions might also appear in humans harboring SLC12A1 mutations.

Aims: Dilated cardiomyopathy (DCM) is one of the leading causes for cardiac transplantations and accounts for up to one-third of all heart failure cases. Since extrinsic and monogenic causes explain only a fraction of all cases, common genetic variants are suspected to contribute to the pathogenesis of DCM, its age of onset, and clinical progression. By a large-scale case-control genome-wide association study we aimed here to identify novel genetic risk loci for DCM., Methods and Results: Applying a three-staged study design, we analysed more than 4100 DCM cases and 7600 controls. We identified and successfully replicated multiple single nucleotide polymorphism on chromosome 6p21. In the combined analysis, the most significant association signal was obtained for rs9262636 (P = 4.90 × 10(-9)) located in HCG22, which could again be replicated in an independent cohort. Taking advantage of expression quantitative trait loci (eQTL) as molecular phenotypes, we identified rs9262636 as an eQTL for several closely located genes encoding class I and class II major histocompatibility complex heavy chain receptors., Conclusion: The present study reveals a novel genetic susceptibility locus that clearly underlines the role of genetically driven, inflammatory processes in the pathogenesis of idiopathic DCM.

Background: GNAS encodes the α subunit of the stimulatory G protein (Gsα). Maternal inherited Gsα mutations cause pseudohypoparathyroidism type Ia (PHP-Ia), associated with shortening of the 4th and 5th metacarpals., Aims: Here we investigated the Gsα pathway in short patients with distinct shortening of the 4th and 5th metacarpals., Methods: In 571 children with short stature and 4 patients with PHP-Ia metacarpal bone lengths were measured. In identified patients we analysed the Gsα protein function in platelets, performed GNAS sequencing, and epigenetic analysis of four significant differentially methylated regions., Results: In 51 patients (8.9%) shortening of the 4th and 5th metacarpals was more pronounced than their height deficit. No GNAS coding mutations were identified in 20 analysed patients, except in 2 PHP-Ia patients. Gsα activity was reduced in all PHP-Ia patients and in 25% of the analysed patients. No significant methylation changes were identified., Conclusions: Our findings suggest that patients with short stature and distinct metacarpal bone shortening could be part of the wide variety of PHP/PPHP, therefore it was worthwhile analysing the Gsα protein function and GNAS gene in these patients in order to further elucidate the phenotype and genotype of Gsα dysfunction.

Uromodulin-associated kidney disease (UAKD) summarizes different clinical features of an autosomal dominant heritable disease syndrome in humans with a proven uromodulin (UMOD) mutation involved. It is often characterized by hyperuricemia, gout, alteration of urine concentrating ability, as well as a variable rate of disease progression inconstantly leading to renal failure and histological alterations of the kidneys. We recently established the two Umod mutant mouse lines Umod(C93F) and Umod(A227T) on the C3H inbred genetic background both showing kidney defects analogous to those found in human UAKD patients. In addition, disease symptoms were revealed that were not yet described in other published mouse models of UAKD. To examine if further organ systems and/or metabolic pathways are affected by Umod mutations as primary or secondary effects, we describe a standardized, systemic phenotypic analysis of the two mutant mouse lines Umod(A227T) and Umod(C93F) in the German Mouse Clinic. Different genotypes as well as different ages were tested. Beside the already published changes in body weight, body composition and bone metabolism, the influence of the Umod mutation on energy metabolism was confirmed. Hematological analysis revealed a moderate microcytic and erythropenic anemia in older Umod mutant mice. Data of the other analyses in 7-10 month-old mutant mice showed single small additional effects.

Osteogenesis imperfecta (OI) is an inherited connective tissue disorder with skeletal dysplasia of varying severity, predominantly caused by mutations in the collagen I genes (COL1A1/COL1A2). Extraskeletal findings such as cardiac and pulmonary complications are generally considered to be significant secondary features. Aga2, a murine model for human OI, was systemically analyzed in the German Mouse Clinic by means of in vivo and in vitro examinations of the cardiopulmonary system, to identify novel mechanisms accounting for perinatal lethality. Pulmonary and, especially, cardiac fibroblast of perinatal lethal Aga2/+ animals display a strong down-regulation of Col1a1 transcripts in vivo and in vitro, resulting in a loss of extracellular matrix integrity. In addition, dysregulated gene expression of Nppa, different types of collagen and Agt in heart and lung tissue support a bone-independent vicious cycle of heart dysfunction, including hypertrophy, loss of myocardial matrix integrity, pulmonary hypertension, pneumonia and hypoxia leading to death in Aga2. These murine findings are corroborated by a pediatric OI cohort study, displaying significant progressive decline in pulmonary function and restrictive pulmonary disease independent of scoliosis. Most participants show mild cardiac valvular regurgitation, independent of pulmonary and skeletal findings. Data obtained from human OI patients and the mouse model Aga2 provide novel evidence for primary effects of type I collagen mutations on the heart and lung. The findings will have potential benefits of anticipatory clinical exams and early intervention in OI patients.

Pseudoxanthoma elasticum (PXE) is an autosomal recessive disorder in which calcification of connective tissue leads to pathology in skin, eye and blood vessels. PXE is caused by mutations in ABCC6. High expression of this transporter in the basolateral hepatocyte membrane suggests that it secretes an as-yet elusive factor into the circulation which prevents ectopic calcification. Utilizing our Abcc6 (-/-) mouse model for PXE, we tested the hypothesis that this factor is vitamin K (precursor) (Borst et al. 2008, Cell Cycle). For 3 months, Abcc6 (-/-) and wild-type mice were put on diets containing either the minimum dose of vitamin K required for normal blood coagulation or a dose that was 100 times higher. Vitamin K was supplied as menaquinone-7 (MK-7). Ectopic calcification was monitored in vivo by monthly micro-CT scans of the snout, as the PXE mouse model develops a characteristic connective tissue mineralization at the base of the whiskers. In addition, calcification of kidney arteries was measured by histology. Results show that supplemental MK-7 had no effect on ectopic calcification in Abcc6 ( -/- ) mice. MK-7 supplementation increased vitamin K levels (in skin, heart and brain) in wild-type and in Abcc6 (-/-) mice. Vitamin K tissue levels did not depend on Abcc6 genotype. In conclusion, dietary MK-7 supplementation increased vitamin K tissue levels in the PXE mouse model but failed to counteract ectopic calcification. Hence, we obtained no support for the hypothesis that Abcc6 transports vitamin K and that PXE can be cured by increasing tissue levels of vitamin K.

Monitoring of direct inhibitors of thrombin (DTI) is critical for their safe and effective use as anticoagulants. We examined samples containing several concentrations of argatroban or lepirudin in reconstituted standard human plasma and plasma from medical outpatients and intensive care patients. Prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin time (TT) were determined using automated analyzers. Ecarin clotting time (ECT) was measured using a 10 IU/mL dilution of ecarin in 0.05 mol/L CaCl(2). Calibration curves were approximately linear for TT and ECT in samples containing argatroban and lepirudin, respectively. Activated partial thromboplastin curves reached a plateau at DTI concentrations ≥2 µg/mL, suggesting that the aPTT may not reliably detect overdosing. Prothrombin time increased exponentially. A broad range of clotting times was seen in patient samples with all tests suggesting that individual morbidity and therapies may strongly influence test results and may lead to underestimation of DTI doses.

Background: Intracerebral haemorrhage is the most feared complication in patients who are on treatment with vitamin K antagonists. Vitamin K antagonist related intracerebral haemorrhage occurs in about 10% of patients. Intracerebral haemorrhage has the worst prognosis of all subtypes of stroke including spontaneous intracerebral haemorrhage, and a mortality rate of up to about 65%. The higher rate of haematoma expansion due to rebleeding is thought to be responsible for the higher mortality. Current international treatment recommendations include fresh frozen plasma and prothrombin complex concentrate. It is known that these substances lower the international normalised ratio, and thus it is assumed that normalisation of coagulopathy may lead to haemostasis and reduction of rebleeding. However, the issue of whether to use fresh frozen plasma or prothrombin complex concentrate for urgent reversal of vitamin K antagonists is unresolved: safety and efficacy of these treatments have never been studied in a randomised controlled trial. Our questions are: how effective are the two substances in normalisation of the international normalized ratio? How feasible is it to apply either of these treatments in an acute situation? What is the safety profile of each of these substances? Is there a difference in haematoma growth and clinical outcome?, Method: We designed a prospective, randomised, controlled multicentre trial to compare biological efficacy and safety of fresh frozen plasma and prothrombin complex concentrate in vitamin K antagonist related intracerebral haemorrhage. The study is observer-blinded for laboratory, neuroradiological, and clinical outcomes. Patients will be included if a computed tomography scan shows an intraparenchymal or subdural haematoma within 12 h after onset of symptoms, if the patient is on treatment with vitamin K antagonists, and the international normalized ratio is ≥2. Primary endpoint is the normalisation of the international normalized ratio (≤1·2) within three-hours after the start of antagonising therapy. Main exclusion criteria are secondary intracerebral haemorrhage, other known coagulopathies, and known acute ischaemic events., Discussion: We discuss the rationale of our trial on the basis of the current recommendations and specific aspects of trial design as, time window, choice of endpoints, dosing of fresh frozen plasma and prothrombin complex concentrate, monitoring and analysis of safety parameters, and rescue treatment., Conclusion: This will be the first prospective trial comparing fresh frozen plasma and prothrombin complex concentrate in the indication of vitamin K antagonist related intracerebral hemorrhage. Recruitment of subjects started in August 2009. Until now, 19 patients have been included., (International Journal of Stroke © 2011 World Stroke Organization. No claim to original US government works.)

ADAR2, an RNA editing enzyme that converts specific adenosines to inosines in certain pre-mRNAs, often leading to amino acid substitutions in the encoded proteins, is mainly expressed in brain. Of all ADAR2-mediated edits, a single one in the pre-mRNA of the AMPA receptor subunit GluA2 is essential for survival. Hence, early postnatal death of mice lacking ADAR2 is averted when the critical edit is engineered into both GluA2 encoding Gria2 alleles. Adar2(-/-)/Gria2(R/R) mice display normal appearance and life span, but the general phenotypic effects of global lack of ADAR2 have remained unexplored. Here we have employed the Adar2(-/-)/Gria2(R/R) mouse line, and Gria2(R/R) mice as controls, to study the phenotypic consequences of loss of all ADAR2-mediated edits except the critical one in GluA2. Our extended phenotypic analysis covering ∼320 parameters identified significant changes related to absence of ADAR2 in behavior, hearing ability, allergy parameters and transcript profiles of brain.

Inhibiting platelet function is a key therapeutic principle in cardiology because platelets play a pivotal role in triggering cardiovascular events. In addition to acetylsalicylic acid, a cyclooxygenase inhibitor, ADP-receptor blockers are frequently used for anti-platelet therapy. This therapy does not abolish platelet activation and aggregation. Platelets may still be activated by alternative routes such as the thrombin receptor-mediated pathway. New, more potent inhibitors of platelet function continue to lower the risk of ischaemic events but several trials and clinical registries have also shown that this advantage was frequently offset by an increased risk of bleeding complications. As a consequence, the individual risk of ischaemia and bleeding of a patient must be taken into consideration to select the platelet inhibitor offering the best benefit-risk ratio. Modern laboratory diagnostics may help to achieve this goal by complementing functional platelet tests with pharmacogenomic analyses consistent with the idea of "personalized medicine".

Model organisms like the mouse are important tools to learn more about gene function in man. Within the last 20 years many mutant mouse lines have been generated by different methods such as ENU mutagenesis, constitutive and conditional knock-out approaches, knock-down, introduction of human genes, and knock-in techniques, thus creating models which mimic human conditions. Due to pleiotropic effects, one gene may have different functions in different organ systems or time points during development. Therefore mutant mouse lines have to be phenotyped comprehensively in a highly standardized manner to enable the detection of phenotypes which might otherwise remain hidden. The German Mouse Clinic (GMC) has been established at the Helmholtz Zentrum München as a phenotyping platform with open access to the scientific community (www.mousclinic.de; [1]). The GMC is a member of the EUMODIC consortium which created the European standard workflow EMPReSSslim for the systemic phenotyping of mouse models (http://www.eumodic.org/[2])., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Purpose: Genetic engineering techniques led to an exponential increase in the number of transgenic and knock-out mouse models. For many genetically modified mice, high throughput echocardiography is an essential part of a systematic screening workflow. Many researchers perform mouse echocardiography in conscious animals to avoid anesthesia-induced impairment of cardiac function. However, it has been controversially discussed whether mice need to be habituated to handling before their cardiac function can be assessed. The aim of this study was to test the influence of training on parameters assessed during conscious mouse echocardiography. In addition, we tested whether a simple and fast echocardiography protocol has sufficient sensitivity and specificity for primary screening., Materials and Methods: Examined parameters include fractional shortening, heart rate and respiratory rate. A total of 139 mice were examined in this study with a total of 587 echocardiograms. 103 mice were examined on five consecutive days (with examinations on day 1 - 4 regarded as training), 36 mice were only examined on day 1 and 5., Results: Fractional shortening, heart rate and respiratory rate did not show any statistically significant difference between day 1 and day 5 in both groups. The sensitivity and specificity of fractional shortening assessment for predicting a homozygote knock out genotype were 86 % and 97 %, respectively., Conclusion: We conclude that conscious mouse echocardiography can be performed in untrained mice. Fractional shortening measurements may suffice for correct phenotyping in a high throughput setting., (© Georg Thieme Verlag KG Stuttgart · New York.)

The bumetanide-sensitive Na(+)-K(+)-2Cl(-) cotransporter NKCC2, located in the thick ascending limb of Henle's loop, plays a critical role in the kidney's ability to concentrate urine. In humans, loss-of-function mutations of the solute carrier family 12 member 1 gene (SLC12A1), coding for NKCC2, cause type I Bartter syndrome, which is characterized by prenatal onset of a severe polyuria, salt-wasting tubulopathy, and hyperreninemia. In this study, we describe a novel chemically induced, recessive mutant mouse line termed Slc12a1(I299F) exhibiting late-onset manifestation of type I Bartter syndrome. Homozygous mutant mice are viable and exhibit severe polyuria, metabolic alkalosis, marked increase in plasma urea but close to normal creatininemia, hypermagnesemia, hyperprostaglandinuria, hypotension,, and osteopenia. Fractional excretion of urea is markedly decreased. In addition, calcium and magnesium excretions are more than doubled compared with wild-type mice, while uric acid excretion is twofold lower. In contrast to hyperreninemia present in human disease, plasma renin concentration in homozygotes is not increased. The polyuria observed in homozygotes may be due to the combination of two additive factors, a decrease in activity of mutant NKCC2 and an increase in medullary blood flow, due to prostaglandin-induced vasodilation, that impairs countercurrent exchange of urea in the medulla. In conclusion, this novel viable mouse line with a missense Slc12a1 mutation exhibits most of the features of type I Bartter syndrome and may represent a new model for the study of this human disease.