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1.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31395499

RESUMO

INTRODUCTION AND OBJECTIVES: The Micra transcatheter pacing system has shown high effectiveness and a lower complication rate than conventional transvenous pacemakers. However, the benefit of the device is unknown in the very old population (≥ 90 years). The aim of this study was to evaluate the safety and effectiveness of Micra in patients ≥ 90 years. METHODS: We present a prospective observational study with consecutive patients aged >70 years who underwent implantation of a Micra pacemaker system. Patients were divided into 2 groups: ≥ 90 and<90 years. RESULTS: The Micra system was implanted in 129 patients, of whom 41 were aged ≥ 90 years and 88<90 years. The device was successfully implanted in 40 (97.6%) patients ≥ 90 years and in 87 (98.9%) patients<90 years (P=.58). An adequate position was achieved with need for ≤ 2 repositions in 97.5% and 91.9% of patients, respectively (P=.32). Procedure time (26.1 ±11.6 vs 30.3 ±14.2minutes; P=.11) and fluoroscopy time (6.4 ±4.7 vs 7.2 ±4.9minutes; P=0.41) were similar in the 2 groups. There were 3 major complications (2.3%), all in the group aged<90 years: 1 cardiac perforation, 1 femoral hematoma, and 1 femoral pseudoaneurysm. Thirteen patients aged ≥ 90 years (31.7%) and 16 patients aged <90 years (18.2%) died during a mean follow-up of 230±233 days and 394±285 days, respectively. There were no device-related deaths. No infection, dislocation or migration of Micra were observed. The electrical performance was optimal at follow-up. CONCLUSION: The Micra leadless pacing system seems to be safe and effective in patients older than 90 years. It may be considered a reasonable alternative to conventional transvenous pacing in this population.

2.
Europace ; 21(10): 1484-1493, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31280323

RESUMO

AIMS: Atrial fibrosis contributes to arrhythmogenesis in atrial fibrillation and can be detected by MRI or electrophysiological mapping. The current study compares the spatial correlation between delayed enhancement (DE) areas to low-voltage areas (LVAs) and to arrhythmogenic areas with spatio-temporal dispersion (ST-Disp) or continuous activity (CA) in atrial fibrillation (AF). METHODS AND RESULTS: Sixteen patients with persistent AF (nine long-standing) underwent DE-magnetic resonance imaging (1.25 mm × 1.25 mm × 2.5 mm) prior to pulmonary vein isolation. Left atrial (LA) voltage mapping was acquired in AF and the regional activation patterns of 7680 AF wavelets were analysed. Sites with ST-Disp or CA were characterized (voltage, duration) and their spatial relationship to DE areas and LVAs <0.5 mV was assessed. Delayed enhancement areas and LVAs covered 55% and 24% (P < 0.01) of total LA surface, respectively. Delayed enhancement area was present at 61% of LVAs, whereas low voltage was present at 28% of DE areas. Most DE areas (72%) overlapped with atrial high-voltage areas (>0.5 mV). Spatio-temporal dispersion and CA more frequently co-localized with LVAs than with DE areas (78% vs. 63%, P = 0.02). Regional bipolar voltage of ST-Disp vs. CA was 0.64 ± 0.47 mV vs. 0.58 ± 0.51 mV. All 28 ST-Disp and 56 CA areas contained electrograms with prolonged duration (115 ± 14 ms) displaying low voltage (0.34 ± 0.11 mV). CONCLUSION: A small portion of DE areas and LVAs harbour the arrhythmogenic areas displaying ST-Disp or CA. Most arrhythmogenic activities co-localized with LVAs, while there was less co-localization with DE areas. There is an important mismatch between DE areas and LVAs which needs to be considered when used as target for catheter ablation.

4.
JACC Clin Electrophysiol ; 4(4): 531-543, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30067494

RESUMO

OBJECTIVES: Left atrial (LA) low-voltage substrate (LVS) potentially slows intra-atrial conduction, which might identify patients at risk for arrhythmia recurrence following pulmonary vein isolation (PVI). BACKGROUND: Up to 50% of patients with persistent atrial fibrillation (AF) have arrhythmia recurrence following PVI, mostly due to arrhythmogenic LA LVS. METHODS: Seventy-two patients with persistent AF underwent electrocardioversion to sinus rhythm and high-density voltage mapping of the left atrium. Invasively measured LA activation time and P-wave duration (PWD; total PWD and LA PWD [measured from -dV/dt in leads V1 and V2 until the end of the P-wave]) on amplified (40 to 50 mm/mV, 100 to 200 mm/s) digitized 12-lead electrocardiography (ECG) were compared with the extent of LA LVS (<0.5 and <1. 0mV). Freedom from arrhythmia following PVI was evaluated in 143 patients with persistent AF stratified according to amplified PWD before ablation. RESULTS: LA LVS resulted in regional conduction delay, which increased LA activation time (r = 0.79). LA PWD strongly correlated with LA activation time (r = 0.96) and LA LVS (r = 0.80). As the first (right atrial) portion of the P-wave (from P-wave beginning until -dV/dt in leads V1 and V2) was not affected by LA LVS, total PWD correlated with LA LVS (r = 0.84). PWD ≥150 ms identified advanced LA LVS with 94.3% sensitivity and 91.7% specificity. One-year arrhythmia freedom following PVI-only was significantly higher in patients with PWD <150 ms (n = 73) compared with those with prolonged PWD ≥150 ms (n = 70) (72.0% vs. 40.8%; p = 0.003). CONCLUSIONS: Advanced arrhythmogenic LVS is associated with significant intra-atrial conduction delay, which is accurately measurable by prolongation of PWD on amplified 12-lead ECG. PWD ≥150 ms during sinus rhythm measured prior to ablation identifies patients with persistent AF who are at increased risk for arrhythmia recurrence following PVI.

7.
Am Heart J ; 181: 16-25, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27823689

RESUMO

BACKGROUND: The early and accurate diagnosis of acute myocardial infarction (AMI) is an important medical and economic challenge. We aimed to prospectively evaluate the performance of the new European Society of Cardiology rapid 0-hour/3-hour (0 h/3 h) rule out protocol for AMI. METHODS: We enrolled 2,727 consecutive patients presenting with suspected AMI without persistent ST-segment elevation to the emergency department in a prospective international multicenter study. The final diagnosis was adjudicated by 2 independent cardiologists. The performance of the 0 h/3 h rule out protocol was evaluated using 4 high-sensitivity (primary analysis) and 3 sensitive cardiac troponin (cTn) assays. RESULTS: Acute myocardial infarction was the final diagnosis in 473 patients (17.3%). Using the 4 high-sensitivity cTn assays, the 0-hour rule out protocol correctly ruled out 99.8% (95% [confidence interval] CI, 98.7%-100%), 99.6% (95% CI, 98.5%-99.9%), 100% (95% CI, 97.9%-100%), and 100% (95% CI, 98.0%-100%) of late presenters (>6 h from chest pain onset). The 3-hour rule out protocol correctly ruled out 99.9% (95% CI, 99.1%-100%), 99.5% (95% CI, 98.3%-99.9%), 100% (95% CI, 98.1%-100%), and 100% (95% CI, 98.2%-100%) of early presenters (<6 h from chest pain onset). Using the 3 sensitive cTn assays, the 0-hour rule out protocol correctly ruled out 99.6% (95% CI, 98.6%-99.9%), 99.0% (95% CI, 96.9%-99.7%), and 99.1% (95% CI, 97.2%-99.8%) of late presenters; and the 3-hour rule out protocol correctly ruled out 99.4% (95% CI, 98.3%-99.8%), 99.2% (95% CI, 97.3%-99.8%), and 99.0% (95% CI, 97.2%-99.7%) of early presenters. Overall, the 0 h/3 h rule out protocol assigned 40% to 60% of patients to rule out. None of the patients assigned rule out died during 3-months follow-up. CONCLUSIONS: The 0 h/3 h rule out protocol seems to allow the accurate rule out of AMI using both high-sensitivity and sensitive cTn measurements in conjunction with clinical assessment. Additional studies are warranted for external validation.


Assuntos
Dor no Peito/diagnóstico , Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Troponina T/sangue , Idoso , Idoso de 80 Anos ou mais , Dor no Peito/sangue , Dor no Peito/etiologia , Protocolos Clínicos , Eletrocardiografia , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/complicações , Estudos Prospectivos , Fatores de Tempo
8.
Am Heart J ; 171(1): 92-102.e1-5, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26699605

RESUMO

UNLABELLED: We aimed to prospectively derive and validate a novel 0-/1-hour algorithm using high-sensitivity cardiac troponin I (hs-cTnI) for the early "rule-out" and "rule-in" of acute myocardial infarction (AMI). METHODS: In a prospective multicenter diagnostic study, we enrolled 1,500 patients presenting with suspected AMI to the emergency department. The final diagnosis was centrally adjudicated by 2 independent cardiologists blinded to hs-cTnI concentrations. The hs-cTnI (Siemens Vista) 0-/1-hour algorithm incorporated measurements performed at baseline and absolute changes within 1 hour, was derived in the first 750 patients (derivation cohort), and then validated in the second 750 (validation cohort). RESULTS: Overall, AMI was the final diagnosis in 16% of patients. Applying the hs-cTnI 0-/1-hour algorithm developed in the derivation cohort to the validation cohort, 57% of patients could be classified as "rule-out"; 10%, as "rule-in"; and 33%, as "observe." In the validation cohort, the sensitivity and the negative predictive value for AMI in the "rule-out" zone were 100% (95% CI 96%-100%) and 100% (95% CI 99%-100%), respectively. The specificity and the positive predictive value (PPV) for AMI in the "rule-in" zone were 96% (95% CI 94%-97%) and 70% (95% CI 60%-79%), respectively. Negative predictive value and positive predictive value of the 0-/1-hour algorithm were higher compared to the standard of care combining hs-cTnI with the electrocardiogram (both P < .001). CONCLUSION: The hs-cTnI 0-/1-hour algorithm performs very well for early rule-out as well as rule-in of AMI. The clinical implications are that used in conjunction with all other clinical information, the 0-/1-hour algorithm will be a safe and effective approach to substantially reduce time to diagnosis.


Assuntos
Algoritmos , Eletrocardiografia , Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/mortalidade , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Fatores de Tempo
9.
Int J Cardiol ; 195: 163-70, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26043151

RESUMO

BACKGROUND: It is currently unknown, whether and to what extent sensitive cardiac troponin (s-cTn) allows shortening of the time required for safe rule-out and rule-in of acute myocardial infarction (AMI). METHODS: We aimed to develop and validate early rule-out and rule-in algorithms for AMI using a thoroughly-examined and commonly used s-cTnI assay in a prospective multicenter study including 2173 patients presenting to the emergency department with suspected AMI. S-cTnI was measured in a blinded fashion at 0 h, 1 h, and 2 h. The final diagnosis was centrally adjudicated by two independent cardiologists. In the derivation cohort (n = 1496), we developed 1h- and 2h-algorithms assigning patients to "rule-out", "rule-in", or "observe". The algorithms were then prospectively validated in the validation cohort (n = 677). RESULTS: AMI was the adjudicated diagnosis in 17% of patients. After applying the s-cTnI 1h-algorithm developed in the derivation cohort to the validation cohort, 65% of patients were classified as "rule-out", 12% as "rule-in", and 23% to "observe". The negative predictive value for AMI in the "rule-out" group was 98.6% (95% CI, 96.9-99.5), the positive predictive value for AMI in the "rule-in" group 76.3% (95% CI, 65.4-85.1). Overall, 30-day mortality was 0.2% in the "rule-out" group, 1.0% in the "observe" group, and 3.0% in the "rule-in" group. Similar results were obtained for the 2h-algorithm. CONCLUSION: When used in conjunction with other clinical information including the ECG, a simple algorithm incorporating s-cTnI values at presentation and after 1h (or 2h) will allow safe rule-out and accurate rule-in of AMI in the majority of patients.


Assuntos
Tempo para o Tratamento , Troponina I , Idoso , Algoritmos , Biomarcadores/análise , Biomarcadores/sangue , Diagnóstico Precoce , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Tempo para o Tratamento/normas , Tempo para o Tratamento/estatística & dados numéricos , Troponina I/análise , Troponina I/sangue
10.
Circulation ; 131(23): 2032-40, 2015 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-25948541

RESUMO

BACKGROUND: Misdiagnosis of acute myocardial infarction (AMI) may significantly harm patients and may result from inappropriate clinical decision values (CDVs) for cardiac troponin (cTn) owing to limitations in the current regulatory process. METHODS AND RESULTS: In an international, prospective, multicenter study, we quantified the incidence of inconsistencies in the diagnosis of AMI using fully characterized and clinically available high-sensitivity (hs) cTn assays (hs-cTnI, Abbott; hs-cTnT, Roche) among 2300 consecutive patients with suspected AMI. We hypothesized that the approved CDVs for the 2 assays are not biologically equivalent and might therefore contribute to inconsistencies in the diagnosis of AMI. Findings were validated by use of sex-specific CDVs and parallel measurements of other hs-cTnI assays. AMI was the adjudicated diagnosis in 473 patients (21%). Among these, 86 patients (18.2%) had inconsistent diagnoses when the approved uniform CDV was used. When sex-specific CDVs were used, 14.1% of female and 22.7% of male AMI patients had inconsistent diagnoses. Using biologically equivalent CDV reduced inconsistencies to 10% (P<0.001). These findings were confirmed with parallel measurements of other hs-cTn assays. The incidence of inconsistencies was only 7.0% for assays with CDVs that were nearly biologically equivalent. Patients with inconsistent AMI had long-term mortality comparable to that of patients with consistent diagnoses (P=NS) and a trend toward higher long-term mortality than patients diagnosed with unstable angina (P=0.05). CONCLUSIONS: Currently approved CDVs are not biologically equivalent and contribute to major inconsistencies in the diagnosis of AMI. One of 5 AMI patients will receive a diagnosis other than AMI if managed with the alternative hs-cTn assay. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00470587.


Assuntos
Erros de Diagnóstico/estatística & dados numéricos , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Miocárdio/metabolismo , Troponina I/sangue , Troponina T/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Seguimentos , Humanos , Incidência , Cooperação Internacional , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Estudos Prospectivos , Valores de Referência , Fatores Sexuais , Taxa de Sobrevida
11.
Circulation ; 131(23): 2041-50, 2015 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-25948542

RESUMO

BACKGROUND: It is unknown whether more sensitive cardiac troponin (cTn) assays maintain their clinical utility in patients with renal dysfunction. Moreover, their optimal cutoff levels in this vulnerable patient population have not previously been defined. METHODS AND RESULTS: In this multicenter study, we examined the clinical utility of 7 more sensitive cTn assays (3 sensitive and 4 high-sensitivity cTn assays) in patients presenting with symptoms suggestive of acute myocardial infarction. Among 2813 unselected patients, 447 (16%) had renal dysfunction (defined as Modification of Diet in Renal Disease-estimated glomerular filtration rate <60 mL·min(-1)·1.73 m(-2)). The final diagnosis was centrally adjudicated by 2 independent cardiologists using all available information, including coronary angiography and serial levels of high-sensitivity cTnT. Acute myocardial infarction was the final diagnosis in 36% of all patients with renal dysfunction. Among patients with renal dysfunction and elevated baseline cTn levels (≥99th percentile), acute myocardial infarction was the most common diagnosis for all assays (range, 45%-80%). In patients with renal dysfunction, diagnostic accuracy at presentation, quantified by the area under the receiver-operator characteristic curve, was 0.87 to 0.89 with no significant differences between the 7 more sensitive cTn assays and further increased to 0.91 to 0.95 at 3 hours. Overall, the area under the receiver-operator characteristic curve in patients with renal dysfunction was only slightly lower than in patients with normal renal function. The optimal receiver-operator characteristic curve-derived cTn cutoff levels in patients with renal dysfunction were significantly higher compared with those in patients with normal renal function (factor, 1.9-3.4). CONCLUSIONS: More sensitive cTn assays maintain high diagnostic accuracy in patients with renal dysfunction. To ensure the best possible clinical use, assay-specific optimal cutoff levels, which are higher in patients with renal dysfunction, should be considered. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00470587.


Assuntos
Testes Diagnósticos de Rotina/métodos , Diagnóstico Precoce , Rim/fisiopatologia , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Troponina T/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Seguimentos , Taxa de Filtração Glomerular/fisiologia , Humanos , Cooperação Internacional , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Valores de Referência , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
Clin Biochem ; 48(4-5): 318-21, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25526883

RESUMO

OBJECTIVE: In clinical cardiology, B-type natriuretic peptide (BNP) is used as a non-invasive surrogate marker for intra-cardiac filling pressures, particularly in patients with heart failure. It is unknown whether and to what extent increase in intravascular volume and/or sympathetic tone while maintaining constant intra-cardiac pressures leads to an increase in levels of BNP in vivo. DESIGN AND METHODS: We aimed to test this hypothesis in an experimental in vivo model of patients directly after off-pump coronary artery bypass grafting admitted to the intensive care unit. These patients require high volumes of intravenous fluids titrated to keep intra-cardiac filling pressures and arterial blood pressure in the normal range while awakening from deep general anesthesia. In 27 consecutive patients, intra-cardiac filling pressures (using a pulmonary artery catheter) and levels of BNP were measured simultaneously every 6h. RESULTS: At 0, 6, 12, and 18h, the pulmonary capillary wedge pressure remained constant (12±4, 13±3, 12±3, and 13±3mmHg, respectively; p=0.351). Similarly, right heart filling pressures did not change during the study period. In contrast, BNP levels increased significantly during the study period: Median levels were 82 [IQR 37-162] pg/ml at 0h, 153 [92-246] pg/ml at 6h, 274 [156-392] pg/ml at 12h, and 320 [200-528] pg/ml at 18h (p<0.001). No significant correlation between BNP levels and pulmonary capillary wedge pressures was found (r=0.052; p=0.604). CONCLUSIONS: After cardiac surgery, BNP cannot be considered a reliable non-invasive surrogate for PCWP. In vivo, substantial BNP secretion occurs independently of PCWP in a setting of increasing intravascular volume and consciousness/sympathetic tone.


Assuntos
Hemodinâmica/fisiologia , Peptídeo Natriurético Encefálico/sangue , Peptídeo Natriurético Encefálico/metabolismo , Pressão Propulsora Pulmonar/fisiologia , Idoso , Biomarcadores/sangue , Ponte de Artéria Coronária/tendências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
14.
Heart ; 100(21): 1708-14, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24968886

RESUMO

OBJECTIVE: Copeptin, a quantitative marker of endogenous stress, seems to provide incremental value in addition to cardiac troponin in the early rule-out of acute myocardial infarction (AMI). Prevalence, characteristics and outcome of acute chest pain patients with causes other than AMI and elevated copeptin are poorly understood. METHODS: A total of 984 consecutive patients with non-cardiac chest pain were selected from a prospective multicentre study of acute chest pain patients presenting to the emergency department. Levels of copeptin were determined in a blinded fashion and considered elevated if above 13 pmol/L (the 97,5th centile of healthy individuals). The final diagnosis was adjudicated by two independent cardiologists. Median duration of follow-up was 756 days. RESULTS: Elevated copeptin levels were seen in 215 patients (22%). In comparison to patients with normal copeptin levels, patients with elevated levels were older, had more pre-existing cardiac and non-cardiac disorders, more silent cardiomyocyte injury and increased haemodynamic stress as quantified by levels of high-sensitivity cardiac troponin T (9.6 ng/L (3.6-18.3) vs 5.8 ng/L (2.9-9.4)) and B-type natriuretic peptide (75 ng/L (37-187) vs 35 ng/L (15-77)) (both p<0.001), more electrocardiographic abnormalities, more often an adjudicated diagnosis of gastroesophageal reflux or bronchitis/pneumonia and higher 2- year mortality (HR 2.9, 95% CI 1.5  to 5.7). The increased mortality rate seemed to be largely explained by age and comorbidities. CONCLUSIONS: Elevated levels of copeptin are present in about one in five patients with non-cardiac chest pain and are associated with aging, cardiac and non-cardiac comorbidities as well as mortality.


Assuntos
Dor Aguda/epidemiologia , Dor no Peito/epidemiologia , Glicopeptídeos/sangue , Medição de Risco/métodos , Dor Aguda/sangue , Dor Aguda/diagnóstico , Adulto , Idoso , Biomarcadores/sangue , Dor no Peito/sangue , Dor no Peito/diagnóstico , Diagnóstico Diferencial , Eletrocardiografia , Feminino , Seguimentos , Alemanha/epidemiologia , Cardiopatias/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Precursores de Proteínas , Curva ROC , Reprodutibilidade dos Testes , Espanha/epidemiologia , Taxa de Sobrevida/tendências , Suíça/epidemiologia , Fatores de Tempo , Troponina T/sangue
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