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1.
Rev Esp Cardiol (Engl Ed) ; 74(6): 502-509, 2021 Jun.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32451223

RESUMO

INTRODUCTION AND OBJECTIVES: Release kinetics of high-sensitivity cardiac troponin (hs-cTn) T and I in patients with acute myocardial infarction (AMI) are incompletely understood. We aimed to assess whether hs-cTnT/I release in early AMI is near linear. METHODS: In a prospective diagnostic multicenter study the acute release of hs-cTnT and hs-cTnI within 1 and 2hours from presentation to the emergency department was quantified using 3 hs-cTnT/I assays in patients with suspected AMI. The primary endpoint was correlation between hs-cTn changes from presentation to 1 hour vs changes from presentation to 2hours, among all AMI patients and different prespecified subgroups. The final diagnosis was adjudicated by 2 independent cardiologists, based on serial hs-cTnT from the serial study blood samples and additional locally measured hs-cTn values. RESULTS: Among 2437 patients with complete hs-cTnT data, AMI was the adjudicated diagnosis in 376 patients (15%). For hs-cTnT, the correlation coefficient between 0- to 1-hour change and 0- to 2 hour change was 0.931 (95%CI, 0.916-0.944), P <.001. Similar findings were obtained with hs-cTnI (Architect) with correlation coefficients between 0- to 1-hour change and 0- to 2 hour change of 0.969 and hs-cTnI (Centaur) of 0.934 (P <.001 for both). Findings were consistent among type 1 and type 2 AMI and in the subgroup of patients presenting very early after chest pain onset. CONCLUSIONS: Patients presenting with early AMI showed a near linear release of hs-cTnT and hs-cTnI. This near linearity provides the pathophysiological basis for rapid diagnostic algorithms using 0- to 1-hour changes as surrogates for 0- to 2 hour or 0- to 3 hour changes. Registered at ClinicalTrials.gov (Identifier: NCT00470587).


Assuntos
Infarto do Miocárdio , Troponina T , Biomarcadores , Humanos , Cinética , Infarto do Miocárdio/diagnóstico , Estudos Prospectivos , Troponina I
3.
Int J Cardiol ; 269: 114-121, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30224031

RESUMO

BACKGROUND: Various scores have been derived for the assessment of syncope patients in the emergency department (ED) but stay inconsistently validated. We aim to compare their performance to the one of a common, easy-to-use CHADS2 score. METHODS: We prospectively enrolled patients ≥ 40 years old presenting with syncope to the ED in a multicenter study. Early clinical judgment (ECJ) of the treating ED-physician regarding the probability of cardiac syncope was quantified. Two independent physicians adjudicated the final diagnosis after 1-year follow-up. Major cardiovascular events (MACE) and death were recorded during 2 years of follow-up. Nine scores were compared by their area under the receiver-operator characteristics curve (AUC) for death, MACE or the diagnosis of cardiac syncope. RESULTS: 1490 patients were available for score validation. The CHADS2-score presented a higher or equally high accuracy for death in the long- and short-term follow-up than other syncope-specific risk scores. This score also performed well for the prediction of MACE in the long- and short-term evaluation and stratified patients with accuracy comparative to OESIL, one of the best performing syncope-specific risk score. All scores performed poorly for diagnosing cardiac syncope when compared to the ECJ. CONCLUSIONS: The CHADS2-score performed comparably to more complicated syncope-specific risk scores in the prediction of death and MACE in ED syncope patients. While better tools incorporating biochemical and electrocardiographic markers are needed, this study suggests that the CHADS2-score is currently a good option to stratify risk in syncope patients in the ED. TRIAL REGISTRATION: NCT01548352.


Assuntos
Eletrocardiografia/normas , Serviço Hospitalar de Emergência/normas , Síncope/diagnóstico , Síncope/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
4.
Eur Heart J ; 39(42): 3780-3794, 2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30169752

RESUMO

Aims: We aimed to evaluate the impact of age on the performance of the European Society of Cardiology (ESC) 0/1h-algorithms and to derive and externally validate alternative cut-offs specific to older patients. Methods and results: We prospectively enrolled patients presenting to the emergency department (ED) with symptoms suggestive of acute myocardial infarction in three large diagnostic studies. Final diagnoses were adjudicated by two independent cardiologists. High-sensitivity cardiac troponin (hs-cTn) T and I concentrations were measured at presentation and after 1 h. Patients were stratified according to age [<55 years (young), ≥55 to <70 years (middle-age), ≥70 years (old)]. Rule-out safety of the ESC hs-cTnT 0/1h-algorithm was very high in all age-strata: sensitivity 100% [95% confidence interval (95% CI) 94.9-100] in young, 99.3% (95% CI 96.0-99.9) in middle-age, and 99.3% (95% CI 97.5-99.8) in old patients. Accuracy of rule-in decreased with age: specificity 97.0% (95% CI 95.8-97.9) in young, 96.1% (95% CI 94.5-97.2) in middle-age, and 92.7% (95% CI 90.7-94.3) in older patients. Triage efficacy decreased with increasing age (young 93%, middle-age 80%, old 55%, P < 0.001). Similar results were found for the ESC hs-cTnT 0/1h-algorithm. Alternative, slightly higher cut-off concentrations optimized for older patients maintained very high safety of rule-out, increased specificity of rule-in (P < 0.01), reduced overall efficacy for hs-cTnT (P < 0.01), while maintaining efficacy for hs-cTnI. Findings were confirmed in two validation cohorts (n = 2767). Conclusion: While safety of the ESC 0/1h-algorithms remained very high, increasing age significantly reduced overall efficacy and the accuracy of rule-in. Alternative slightly higher cut-off concentrations may be considered for older patients, particularly if using hs-cTnI. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT00470587, number NCT00470587 and NCT02355457 (BACC).


Assuntos
Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Adulto , Fatores Etários , Idoso , Algoritmos , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Sensibilidade e Especificidade , Troponina/sangue
5.
Circulation ; 138(10): 989-999, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-29691270

RESUMO

BACKGROUND: Combining 2 signals of cardiomyocyte injury, cardiac troponin I (cTnI) and T (cTnT), might overcome some individual pathophysiological and analytical limitations and thereby increase diagnostic accuracy for acute myocardial infarction with a single blood draw. We aimed to evaluate the diagnostic performance of combinations of high-sensitivity (hs) cTnI and hs-cTnT for the early diagnosis of acute myocardial infarction. METHODS: The diagnostic performance of combining hs-cTnI (Architect, Abbott) and hs-cTnT (Elecsys, Roche) concentrations (sum, product, ratio, and a combination algorithm) obtained at the time of presentation was evaluated in a large multicenter diagnostic study of patients with suspected acute myocardial infarction. The optimal rule-out and rule-in thresholds were externally validated in a second large multicenter diagnostic study. The proportion of patients eligible for early rule-out was compared with the European Society of Cardiology 0/1 and 0/3 hour algorithms. RESULTS: Combining hs-cTnI and hs-cTnT concentrations did not consistently increase overall diagnostic accuracy as compared with the individual isoforms. However, the combination improved the proportion of patients meeting criteria for very early rule-out. With the European Society of Cardiology 2015 guideline recommended algorithms and cut-offs, the proportion meeting rule-out criteria after the baseline blood sampling was limited (6% to 24%) and assay dependent. Application of optimized cut-off values using the sum (9 ng/L) and product (18 ng2/L2) of hs-cTnI and hs-cTnT concentrations led to an increase in the proportion ruled-out after a single blood draw to 34% to 41% in the original (sum: negative predictive value [NPV] 100% [95% confidence interval (CI), 99.5% to 100%]; product: NPV 100% [95% CI, 99.5% to 100%]) and in the validation cohort (sum: NPV 99.6% [95% CI, 99.0-99.9%]; product: NPV 99.4% [95% CI, 98.8-99.8%]). The use of a combination algorithm (hs-cTnI <4 ng/L and hs-cTnT <9 ng/L) showed comparable results for rule-out (40% to 43% ruled out; NPV original cohort 99.9% [95% CI, 99.2-100%]; NPV validation cohort 99.5% [95% CI, 98.9-99.8%]) and rule-in (positive predictive value [PPV] original cohort 74.4% [95% Cl, 69.6-78.8%]; PPV validation cohort 84.0% [95% Cl, 79.7-87.6%]). CONCLUSIONS: New strategies combining hs-cTnI and hs-cTnT concentrations may significantly increase the number of patients eligible for very early and safe rule-out, but do not seem helpful for the rule-in of acute myocardial infarction. CLINICAL TRIAL REGISTRATION: URL (APACE): https://www.clinicaltrial.gov . Unique identifier: NCT00470587. URL (ADAPT): www.anzctr.org.au . Unique identifier: ACTRN12611001069943.


Assuntos
Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Troponina T/sangue , Austrália , Biomarcadores/sangue , Diagnóstico Precoce , Europa (Continente) , Humanos , Infarto do Miocárdio/sangue , Nova Zelândia , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Tempo , Regulação para Cima
6.
Circulation ; 136(16): 1495-1508, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-28972002

RESUMO

BACKGROUND: Cardiac myosin-binding protein C (cMyC) is a cardiac-restricted protein that is more abundant than cardiac troponins (cTn) and is released more rapidly after acute myocardial infarction (AMI). We evaluated cMyC as an adjunct or alternative to cTn in the early diagnosis of AMI. METHODS: Unselected patients (N=1954) presenting to the emergency department with symptoms suggestive of AMI, concentrations of cMyC, and high-sensitivity (hs) and standard-sensitivity cTn were measured at presentation. The final diagnosis of AMI was independently adjudicated using all available clinical and biochemical information without knowledge of cMyC. The prognostic end point was long-term mortality. RESULTS: Final diagnosis was AMI in 340 patients (17%). Concentrations of cMyC at presentation were significantly higher in those with versus without AMI (median, 237 ng/L versus 13 ng/L, P<0.001). Discriminatory power for AMI, as quantified by the area under the receiver-operating characteristic curve (AUC), was comparable for cMyC (AUC, 0.924), hs-cTnT (AUC, 0.927), and hs-cTnI (AUC, 0.922) and superior to cTnI measured by a contemporary sensitivity assay (AUC, 0.909). The combination of cMyC with hs-cTnT or standard-sensitivity cTnI (but not hs-cTnI) led to an increase in AUC to 0.931 (P<0.0001) and 0.926 (P=0.003), respectively. Use of cMyC more accurately classified patients with a single blood test into rule-out or rule-in categories: Net Reclassification Improvement +0.149 versus hs-cTnT, +0.235 versus hs-cTnI (P<0.001). In early presenters (chest pain <3 h), the improvement in rule-in/rule-out classification with cMyC was larger compared with hs-cTnT (Net Reclassification Improvement +0.256) and hs-cTnI (Net Reclassification Improvement +0.308; both P<0.001). Comparing the C statistics, cMyC was superior to hs-cTnI and standard sensitivity cTnI (P<0.05 for both) and similar to hs-cTnT at predicting death at 3 years. CONCLUSIONS: cMyC at presentation provides discriminatory power comparable to hs-cTnT and hs-cTnI in the diagnosis of AMI and may perform favorably in patients presenting early after symptom onset. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00470587.


Assuntos
Proteínas de Transporte/sangue , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Troponina T/sangue , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Biomarcadores/sangue , Diagnóstico Precoce , Serviço Hospitalar de Emergência , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/terapia , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Reprodutibilidade dos Testes , Fatores de Tempo , Triagem , Regulação para Cima
7.
Clin Chem ; 63(7): 1227-1236, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28515106

RESUMO

BACKGROUND: We compared 2 high-sensitivity cardiac troponin (hs-cTn)-based 2-h strategies in patients presenting with suspected acute myocardial infarction (AMI) to the emergency department (ED): the 2-h accelerated diagnostic protocol (2h-ADP) combining hs-cTn, electrocardiogram, and a risk score, and the 2-h algorithm exclusively based on hs-cTn concentrations and their absolute changes. METHODS: Analyses were performed in 2 independent diagnostic cohorts [European Advantageous Predictors of Acute Coronary Syndrome Evaluation (APACE) study, Australian-New Zealand 2-h Accelerated Diagnostic Protocol to Assess patients with chest Pain symptoms using contemporary Troponins as the only biomarker (ADAPT) study] employing hs-cTnT (Elecsys) and hs-cTnI (Architect). The final diagnosis was adjudicated by 2 independent cardiologists. RESULTS: AMI was the final diagnosis in 16.5% (95% CI, 14.6%-18.6%) of the 1372 patients in APACE, and 12.6% (95% CI, 10.7%-14.7%) of 1153 patients in ADAPT. The negative predictive value (NPV) and sensitivity for AMI were very high and comparable with both strategies using either hs-cTnT or hs-cTnI in both cohorts (all statistical comparisons nonsignificant). The percentage of patients triaged toward rule-out was significantly lower with the 2h-ADP (36%-43%) vs the 2-h algorithm (55%-68%) with both assays and in both cohorts (P < 0.001). The sensitivity of the 2h-ADP was higher for 30-day major adverse cardiovascular events. CONCLUSIONS: Both algorithms provided very high and comparable safety as quantified by the NPV and sensitivity for AMI and major adverse cardiac events (MACE) at 30 days in patients triaged toward rule-out, although sensitivity for MACE at 30 days was lower with both algorithms in cohort 2. Although the 2-h algorithm was more efficacious, not all patients ruled out for AMI by this algorithm were appropriate candidates for early discharge. The 2h-ADP seems superior in the selection of patients for early discharge from the ED. CLINICAL TRIAL REGISTRATION: APACE: http://clinicaltrials.gov/show/NCT00470587ADAPT: Australia-New Zealand Clinical Trials Registry ACTRN12611001069943.


Assuntos
Algoritmos , Técnicas de Diagnóstico Cardiovascular/normas , Infarto do Miocárdio/diagnóstico , Idoso , Feminino , Humanos , Masculino , Infarto do Miocárdio/sangue , Estudos Prospectivos , Troponina I/sangue , Troponina T/sangue
8.
Circulation ; 135(17): 1597-1611, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28283497

RESUMO

BACKGROUND: Four strategies for very early rule-out of acute myocardial infarction using high-sensitivity cardiac troponin I (hs-cTnI) have been identified. It remains unclear which strategy is most attractive for clinical application. METHODS: We prospectively enrolled unselected patients presenting to the emergency department with symptoms suggestive of acute myocardial infarction. The final diagnosis was adjudicated by 2 independent cardiologists. Hs-cTnI levels were measured at presentation and after 1 hour in a blinded fashion. We directly compared all 4 hs-cTnI-based rule-out strategies: limit of detection (LOD, hs-cTnI<2 ng/L), single cutoff (hs-cTnI<5 ng/L), 1-hour algorithm (hs-cTnI<5 ng/L and 1-hour change<2 ng/L), and the 0/1-hour algorithm recommended in the European Society of Cardiology guideline combining LOD and 1-hour algorithm. RESULTS: Among 2828 enrolled patients, acute myocardial infarction was the final diagnosis in 451 (16%) patients. The LOD approach ruled out 453 patients (16%) with a sensitivity of 100% (95% confidence interval [CI], 99.2%-100%), the single cutoff 1516 patients (54%) with a sensitivity of 97.1% (95% CI, 95.1%-98.3%), the 1-hour algorithm 1459 patients (52%) with a sensitivity of 98.4% (95% CI, 96.8%-99.2%), and the 0/1-hour algorithm 1463 patients (52%) with a sensitivity of 98.4% (95% CI, 96.8%-99.2%). Predefined subgroup analysis in early presenters (≤2 hours) revealed significantly lower sensitivity (94.2%, interaction P=0.03) of the single cutoff, but not the other strategies. Two-year survival was 100% with LOD and 98.1% with the other strategies (P<0.01 for LOD versus each of the other strategies). CONCLUSIONS: All 4 rule-out strategies balance effectiveness and safety equally well. The single cutoff should not be applied in early presenters, whereas the 3 other strategies seem to perform well in this challenging subgroup. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00470587.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Técnicas de Apoio para a Decisão , Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/mortalidade , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Biomarcadores/sangue , Eletrocardiografia , Europa (Continente) , Feminino , Nível de Saúde , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/mortalidade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores Sexuais , Fatores de Tempo , Regulação para Cima
9.
World J Cardiol ; 9(1): 65-70, 2017 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-28163839

RESUMO

In patients with history of coronary artery disease angina pectoris is usually attributed to the progression of atherosclerotic lesions. However, in patients with previous coronary artery bypass graft operation (CABG) using internal mammary artery grafts, great vessel disease should also be considered. Herein we present two patients with history of CABG whose symptoms were suspicious for coronary ischemia. During cardiac catheterization reverse blood flow was observed from the left artery disease to the left internal mammary artery (LIMA) graft in both cases. After angioplasty and stent implantation of the left subclavian artery antegrade flow was restored in the LIMA grafts and both patients had complete resolution of symptoms.

10.
J Am Heart Assoc ; 6(12)2017 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-29426039

RESUMO

BACKGROUND: The early detection of cardiac syncope is challenging. We aimed to evaluate the diagnostic value of 4 novel prohormones, quantifying different neurohumoral pathways, possibly involved in the pathophysiological features of cardiac syncope: midregional-pro-A-type natriuretic peptide (MRproANP), C-terminal proendothelin 1, copeptin, and midregional-proadrenomedullin. METHODS AND RESULTS: We prospectively enrolled unselected patients presenting with syncope to the emergency department (ED) in a diagnostic multicenter study. ED probability of cardiac syncope was quantified by the treating ED physician using a visual analogue scale. Prohormones were measured in a blinded manner. Two independent cardiologists adjudicated the final diagnosis on the basis of all clinical information, including 1-year follow-up. Among 689 patients, cardiac syncope was the adjudicated final diagnosis in 125 (18%). Plasma concentrations of MRproANP, C-terminal proendothelin 1, copeptin, and midregional-proadrenomedullin were all significantly higher in patients with cardiac syncope compared with patients with other causes (P<0.001). The diagnostic accuracies for cardiac syncope, as quantified by the area under the curve, were 0.80 (95% confidence interval [CI], 0.76-0.84), 0.69 (95% CI, 0.64-0.74), 0.58 (95% CI, 0.52-0.63), and 0.68 (95% CI, 0.63-0.73), respectively. In conjunction with the ED probability (0.86; 95% CI, 0.82-0.90), MRproANP, but not the other prohormone, improved the area under the curve to 0.90 (95% CI, 0.87-0.93), which was significantly higher than for the ED probability alone (P=0.003). An algorithm to rule out cardiac syncope combining an MRproANP level of <77 pmol/L and an ED probability of <20% had a sensitivity and a negative predictive value of 99%. CONCLUSIONS: The use of MRproANP significantly improves the early detection of cardiac syncope among unselected patients presenting to the ED with syncope. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01548352.


Assuntos
Adrenomedulina/sangue , Fator Natriurético Atrial/sangue , Diagnóstico Precoce , Endotelina-1/sangue , Glicopeptídeos/sangue , Fragmentos de Peptídeos/sangue , Precursores de Proteínas/sangue , Síncope/diagnóstico , Idoso , Biomarcadores/sangue , Serviço Hospitalar de Emergência , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Síncope/sangue , Síncope/fisiopatologia
11.
Eur Heart J ; 36(18): 1123-35a, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25163546

RESUMO

AIM: Numerous genes are known to cause dilated cardiomyopathy (DCM). However, until now technological limitations have hindered elucidation of the contribution of all clinically relevant disease genes to DCM phenotypes in larger cohorts. We now utilized next-generation sequencing to overcome these limitations and screened all DCM disease genes in a large cohort. METHODS AND RESULTS: In this multi-centre, multi-national study, we have enrolled 639 patients with sporadic or familial DCM. To all samples, we applied a standardized protocol for ultra-high coverage next-generation sequencing of 84 genes, leading to 99.1% coverage of the target region with at least 50-fold and a mean read depth of 2415. In this well characterized cohort, we find the highest number of known cardiomyopathy mutations in plakophilin-2, myosin-binding protein C-3, and desmoplakin. When we include yet unknown but predicted disease variants, we find titin, plakophilin-2, myosin-binding protein-C 3, desmoplakin, ryanodine receptor 2, desmocollin-2, desmoglein-2, and SCN5A variants among the most commonly mutated genes. The overlap between DCM, hypertrophic cardiomyopathy (HCM), and channelopathy causing mutations is considerably high. Of note, we find that >38% of patients have compound or combined mutations and 12.8% have three or even more mutations. When comparing patients recruited in the eight participating European countries we find remarkably little differences in mutation frequencies and affected genes. CONCLUSION: This is to our knowledge, the first study that comprehensively investigated the genetics of DCM in a large-scale cohort and across a broad gene panel of the known DCM genes. Our results underline the high analytical quality and feasibility of Next-Generation Sequencing in clinical genetic diagnostics and provide a sound database of the genetic causes of DCM.


Assuntos
Cardiomiopatia Dilatada/genética , Análise de Sequência de DNA/métodos , Cardiomiopatia Dilatada/diagnóstico , Europa (Continente) , Estudos de Viabilidade , Feminino , Marcadores Genéticos/genética , Genótipo , Heterozigoto , Humanos , Masculino , Mutação/genética , Fenótipo , Características de Residência
12.
BMC Genomics ; 15: 622, 2014 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-25052024

RESUMO

BACKGROUND: Genome wide association studies (GWAS) are applied to identify genetic loci, which are associated with complex traits and human diseases. Analogous to the evolution of gene expression analyses, pathway analyses have emerged as important tools to uncover functional networks of genome-wide association data. Usually, pathway analyses combine statistical methods with a priori available biological knowledge. To determine significance thresholds for associated pathways, correction for multiple testing and over-representation permutation testing is applied. RESULTS: We systematically investigated the impact of three different permutation test approaches for over-representation analysis to detect false positive pathway candidates and evaluate them on genome-wide association data of Dilated Cardiomyopathy (DCM) and Ulcerative Colitis (UC). Our results provide evidence that the gold standard - permuting the case-control status - effectively improves specificity of GWAS pathway analysis. Although permutation of SNPs does not maintain linkage disequilibrium (LD), these permutations represent an alternative for GWAS data when case-control permutations are not possible. Gene permutations, however, did not add significantly to the specificity. Finally, we provide estimates on the required number of permutations for the investigated approaches. CONCLUSIONS: To discover potential false positive functional pathway candidates and to support the results from standard statistical tests such as the Hypergeometric test, permutation tests of case control data should be carried out. The most reasonable alternative was case-control permutation, if this is not possible, SNP permutations may be carried out. Our study also demonstrates that significance values converge rapidly with an increasing number of permutations. By applying the described statistical framework we were able to discover axon guidance, focal adhesion and calcium signaling as important DCM-related pathways and Intestinal immune network for IgA production as most significant UC pathway.


Assuntos
Cardiomiopatia Dilatada/genética , Colite Ulcerativa/genética , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla , Genômica/métodos , Cardiomiopatia Dilatada/patologia , Colite Ulcerativa/patologia , Humanos , Polimorfismo de Nucleotídeo Único/genética , Transdução de Sinais/genética
13.
Vasa ; 43(3): 163-70, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24797047

RESUMO

Peripheral artery disease (PAD) is a marker disease for generalized atherosclerosis and represents one of the world's major causes of morbidity and mortality. Many studies have tried to gain insight into the molecular mechanisms involved in PAD onset, progression and prognosis. In the last decade, small non-coding RNAs, termed miRNAs, have emerged as a major research focus due to their regulating function of multiple gene sets. In the cardiovascular system, miRNAs not only impact on physiological pathways like cardiac development and angiogenesis, but also play an important role in disease mechanisms and progression of myocardial hypertrophy, acute myocardial infarction, heart failure or arrhythmias. New insights lend considerable support to the concept of miRNAs serving as highly sensitive biomarkers and therapeutic targets. To date, a comprehensive understanding of miRNA regulation of angiogenesis and maintenance of vascular integrity in PAD remains less explored. In this review, we discuss current studies and highlight the potential of miRNAs not only to act as a diagnostic tool, but also to facilitate innovative strategies for gene therapy.


Assuntos
Artérias/metabolismo , MicroRNAs/metabolismo , Doença Arterial Periférica/genética , Animais , Artérias/patologia , Artérias/fisiopatologia , Regulação da Expressão Gênica , Marcadores Genéticos , Terapia Genética/métodos , Humanos , MicroRNAs/sangue , MicroRNAs/uso terapêutico , Neovascularização Fisiológica , Doença Arterial Periférica/sangue , Doença Arterial Periférica/patologia , Doença Arterial Periférica/fisiopatologia , Doença Arterial Periférica/terapia
14.
Eur Heart J ; 34(36): 2812-22, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23864135

RESUMO

AIMS: Non-ischaemic heart failure is one of the today's most prevalent cardiovascular disorders. Since modern pharmacotherapy has proved to be very effective in delaying disease progression and preventing death, imaging modalities and molecular biomarkers play an important role in early identification and clinical management as well as risk assessment of patients. The present study evaluated for the first time whole peripheral blood miRNAs as novel biomarker candidates for non-ischaemic heart failure with reduced ejection fraction (HF-REF). METHODS AND RESULTS: We assessed genome-wide miRNA expression profiles in 53 HF-REF patients and 39 controls. We could identify and validate several miRNAs that show altered expression levels in non-ischaemic HF-REF, discriminating cases from controls both as single markers or when combined in a multivariate signature. In addition, we demonstrate that the miRNAs of this signature significantly correlate with disease severity as indicated by left ventricular ejection fraction. CONCLUSION: Our data further denote that miRNAs are potential biomarkers for systolic heart failure. Since their detection levels in whole blood are also related to the degree of left ventricular dysfunction, they may serve as objective molecular tools to assess disease severity and prognosis.


Assuntos
Insuficiência Cardíaca Sistólica/diagnóstico , MicroRNAs/metabolismo , Biomarcadores/metabolismo , Estudos de Casos e Controles , Feminino , Estudo de Associação Genômica Ampla , Insuficiência Cardíaca Sistólica/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/metabolismo , Fragmentos de Peptídeos/metabolismo , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia
15.
Clin Chem ; 59(2): 410-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23255549

RESUMO

BACKGROUND: Alterations in microRNA (miRNA) expression patterns in whole blood may be useful biomarkers of diverse cardiovascular disorders. We previously reported that miRNAs are significantly dysregulated in acute myocardial infarction (AMI) and applied machine-learning techniques to define miRNA subsets with high diagnostic power for AMI diagnosis. However, the kinetics of the time-dependent sensitivity of these novel miRNA biomarkers remained unknown. METHODS: To characterize temporal changes in the expressed human miRNAs (miRNome), we performed here the first whole-genome miRNA kinetic study in AMI patients. We measured miRNA expression levels at multiple time points (0, 2, 4, 12, 24 h after initial presentation) in patients with acute ST-elevation myocardial infarction by using microfluidic primer extension arrays and quantitative real-time PCR. As a prerequisite, all patients enrolled had to have cardiac troponin T concentrations <50 ng/L on admission as measured with a high-sensitivity assay. RESULTS: We found a subset of miRNAs to be significantly dysregulated both at initial presentation and during the course of AMI. Additionally, we identified novel miRNAs that are dysregulated early during myocardial infarction, such as miR-1915 and miR-181c*. CONCLUSIONS: The present proof-of-concept study provides novel insights into the dynamic changes of the human miRNome during AMI.


Assuntos
MicroRNAs/sangue , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Biomarcadores/sangue , Feminino , Genômica , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Troponina I/sangue
16.
Mol Cell Biol ; 31(16): 3424-35, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21670146

RESUMO

Integrin-linked kinase (ILK) is an essential component of the cardiac mechanical stretch sensor and is bound in a protein complex with parvin and PINCH proteins, the so-called ILK-PINCH-parvin (IPP) complex. We have recently shown that inactivation of ILK or ß-parvin activity leads to heart failure in zebrafish via reduced protein kinase B (PKB/Akt) activation. Here, we show that PINCH proteins localize at sarcomeric Z disks and costameres in the zebrafish heart and skeletal muscle. To investigate the in vivo role of PINCH proteins for IPP complex stability and PKB signaling within the vertebrate heart, we inactivated PINCH1 and PINCH2 in zebrafish. Inactivation of either PINCH isoform independently leads to instability of ILK, loss of stretch-responsive anf and vegf expression, and progressive heart failure. The predominant cause of heart failure in PINCH morphants seems to be loss of PKB activity, since PKB phosphorylation at serine 473 is significantly reduced in PINCH-deficient hearts and overexpression of constitutively active PKB reconstitutes cardiac function in PINCH morphants. These findings highlight the essential function of PINCH proteins in controlling cardiac contractility by granting IPP/PKB-mediated signaling.


Assuntos
Proteínas Musculares/fisiologia , Contração Miocárdica , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia , Proteínas de Peixe-Zebra/fisiologia , Animais , Insuficiência Cardíaca/etiologia , Músculo Esquelético , Miocárdio/química , Miocárdio/enzimologia , Fosforilação , Sarcômeros/química , Peixe-Zebra
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