RESUMO
Vasospastic angina (VSA), or variant angina, is an under-recognized cause of chest pain and myocardial infarction, especially in Western countries. VSA leads to a declined quality of life and is associated with increased morbidity and mortality. Currently, the diagnosis of VSA relies on invasive testing that requires the direct intracoronary administration of ergonovine or acetylcholine. However, invasive vasoreactivity testing is underutilized. Several non-invasive imaging alternatives have been proposed to screen for VSA. This review aims to discuss the strengths and limitations of available non-invasive imaging tests for vasospastic angina.
Assuntos
Vasoespasmo Coronário , Humanos , Qualidade de Vida , Ergonovina , Eletrocardiografia , Acetilcolina , Angiografia Coronária/métodosRESUMO
BACKGROUND: A drop in blood pressure (BP) or blunted BP response is an established high-risk marker during exercise myocardial perfusion imaging (MPI); however, data are sparse regarding the prognostic value of BP response in patients undergoing vasodilator stress rubidium-82 (Rb-82) Positron Emission Tomography (PET) MPI. METHODS AND RESULTS: From the PET Prognosis Multicenter Registry, a cohort of 3413 patients underwent vasodilator stress Rb-82 PET MPI with dipyridamole or adenosine. We used multivariable Cox proportional hazard regression to analyze the association with mortality of four BP variables: stress minus rest systolic BP (∆SBP), stress minus rest diastolic BP (∆DBP), resting systolic BP (rSBP), and resting diastolic BP (rDBP). Covariates that had univariate P values <.10 were entered into the multivariable model. After median 1.7 years follow-up, 270 patients died. In univariate analyses, ∆SBP (P = .082), rSBP (P = .008), and rDBP (P < .001) were of potential prognostic value (P < .10), but ∆DBP was not (P = .96). After adjustment for other clinical and MPI variables, ∆SBP no longer independently predicted mortality (P = .082); only lower rSBP (P = .026) and lower rDBP (P = .045) remained independently prognostic. CONCLUSIONS: In patients undergoing vasodilator stress MPI, only lower resting BP is an independent predictor of mortality along with other clinical and MPI variables; BP response does not appear to add to risk stratification in these patients.
Assuntos
Pressão Sanguínea/efeitos dos fármacos , Imagem de Perfusão do Miocárdio/métodos , Tomografia por Emissão de Pósitrons/métodos , Radioisótopos de Rubídio , Vasodilatadores/farmacologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Sistema de RegistrosRESUMO
BACKGROUND: Small studies have yielded divergent results for administration of granulocyte colony-stimulating factor (G-CSF) after acute myocardial infarction. Adequately powered studies involving patients with at least moderate left ventricular dysfunction are lacking. METHODS: Patients with left ventricular ejection fraction less than 45% after anterior-wall myocardial infarction were treated with G-CSF (10 µg/kg daily for 4 days) or placebo. After initial randomization of 86 patients, 41 in the placebo group and 39 in the G-CSF group completed 6-month follow-up and underwent measurement of left ventricular ejection fraction by radionuclide angiography. RESULTS: Baseline and 6-week mean ejection fraction was similar for the G-CSF and placebo groups: 34.8% (95% confidence interval [CI] 32.6%-37.0%) v. 36.4% (95% CI 33.5%-39.2%) at baseline and 39.8% (95% CI 36.2%-43.4%) v. 43.1% (95% CI 39.2%-47.0%) at 6 weeks. However, G-CSF therapy was associated with a lower ejection fraction at 6 months relative to placebo (40.8% [95% CI 37.4%-44.2%] v. 46.0% [95% CI 42.7%-44.3%]). Both groups had improved left ventricular function, but change in left ventricular ejection fraction was lower in patients treated with G-CSF than in those who received placebo (5.7 [95% CI 3.4-8.1] percentage points v. 9.2 [95% CI 6.3-12.1] percentage points). One or more of a composite of several major adverse cardiac events occurred in 8 patients (19%) within each group, with similar rates of target-vessel revascularization. INTERPRETATION: In patients with moderate left ventricular dysfunction following anterior-wall infarction, G-CSF therapy was associated with a lower 6-month left ventricular ejection fraction but no increased risk of major adverse cardiac events. Future studies of G-CSF in patients with left ventricular dysfunction should be monitored closely for safety. TRIAL REGISTRATION: ClinicalTrials.gov, no. NCT00394498.
Assuntos
Infarto Miocárdico de Parede Anterior/terapia , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas/métodos , Disfunção Ventricular Esquerda/terapia , Infarto Miocárdico de Parede Anterior/etiologia , Infarto Miocárdico de Parede Anterior/fisiopatologia , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Cintilografia , Volume Sistólico , Resultado do Tratamento , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Remodelação VentricularRESUMO
AIMS: Cardiac resynchronization therapy (CRT) benefits patients with heart failure and a wide QRS complex. Still, one-third derive no clinical benefit and a majority of patients demonstrate no objective improvement of left ventricular (LV) function. Left bundle branch block (LBBB) is a strong predictor of response to CRT. We evaluated whether absence of electrocardiogram (ECG) markers of residual left bundle (LB) conduction in guideline-defined LBBB predicted a greater response to CRT. METHODS AND RESULTS: An r wave ≥1 mm in lead V1 (r-V1) and/or a q wave ≥1 mm in lead aVL (q-aVL) was used to identify patients with residual LB conduction. Forty patients with a wide QRS were prospectively enrolled and subdivided into three groups: complete LBBB (cLBBB), LBBB without r-V1 or q-aVL (n = 12); LBBB with residual LB conduction (rLBBB), LBBB with r-V1 and/or q-aVL (n = 15); and non-specific intraventricular conduction delay (IVCD), (n = 13). Following CRT: mean change in left ventricular ejection fraction was 11.9 ± 11.9% in cLBBB, 3.8 ± 5.4% in rLBBB (P= 0.045), and 2.5 ± 4.4% in IVCD (P= 0.02 cLBBB vs. IVCD); mean reduction in left ventricular end-systolic volume was 26.4 ± 39.2% in cLBBB, 14.3 ± 22.9% in rLBBB (P= 0.35), and 5.6 ± 17.3% in IVCD (P= 0.11 cLBBB vs. IVCD); mean change in native QRS duration was -8.0 ± 11.0 ms in cLBBB, -0.8 ± 8.24 ms in rLBBB (P= 0.07), and 0.15 ± 8.0 ms in IVCD (P= 0.048 cLBBB vs. IVCD). CONCLUSION: In patients with guideline-defined LBBB, the absence of ECG markers of residual LB conduction was predictive of a greater improvement in LV function with CRT.
Assuntos
Bloqueio de Ramo/fisiopatologia , Terapia de Ressincronização Cardíaca/métodos , Sistema de Condução Cardíaco/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Idoso , Bloqueio de Ramo/diagnóstico , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Volume Sistólico/fisiologia , Resultado do Tratamento , Função Ventricular Esquerda/fisiologiaRESUMO
BACKGROUND: Serial conventional cardiac troponin (cTn) measurements 6-9 hours apart are recommended for non-ST-elevation MI (NSTEMI) diagnosis. We sought to develop a pathway with 3-hour changes for major adverse cardiac event (MACE) identification and assess the added value of the HEART [History, Electrocardiogram (ECG), Age, Risk factors, Troponin] score to the pathway. METHODS: We prospectively enrolled adults with NSTEMI symptoms at two-large emergency departments (EDs) over 32-months. Patients with STEMI, unstable angina and one cTn were excluded. We collected baseline characteristics, Siemens Vista conventional cTnI at 0, 3 or 6-hours after ED presentation; HEART score predictors; disposition and ED length of stay (LOS). Adjudicated primary outcome was 15-day MACE (acute MI, revascularization, or death due to cardiac ischemia/unknown cause). We analyzed multiples of 99th percentile cut-off cTnI values (45, 100 and 250ng/L). RESULTS: 1,683 patients (mean age 64.7 years; 55.3% female; median LOS 7-hours; 88 patients with 15-day MACE) were included. 1,346 (80.0%) patients with both cTnI≤45 ng/L; and 155 (9.2%) of the 213 patients with one value≥100ng/L but both<250ng/L or ≤20% change did not suffer MACE. Among 124 patients (7.4%) with one of the two values>45ng/L but<100ng/L based on 3 or 6-hour cTnI, one patient with absolute change<10ng/L and 6 of the 19 patients with≥20ng/L were diagnosed with NSTEMI (patients with Δ10-19ng/L between first and second cTnI had third one at 6-hours). Based on the results, we developed the Ottawa Troponin Pathway (OTP) with a 98.9% sensitivity (95% CI 93.8-100%) and 94.6% specificity (95% CI 93.3-95.6%). Addition of the HEART score improved the sensitivity to 100% (95% CI 95.9-100%) and decreased the specificity to 26.5% (95% CI 24.3-28.7%). CONCLUSION: The OTP with conventional cTnI 3-hours apart, should lead to better NSTEMI identification particularly those with values >99th percentile, standardize management and reduce the ED LOS.
Assuntos
Miocárdio/metabolismo , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio sem Supradesnível do Segmento ST/metabolismo , Troponina I/metabolismo , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , PrognósticoRESUMO
Rudolph Virchow (1821-1902) recognized inflammation in histological preparations of coronary arteries and proposed that inflammation plays a causal role in atherosclerosis. Despite this seminal observation, the main focus of research and drug development programs has been cholesterol alone, and inflammation received less attention over time. However, during the past several decades extensive observations supported the importance of inflammation in the development and destabilization of atherosclerosis. Studies in patients affected by rheumatological diseases suggested an interaction between chronic inflammation and atherosclerotic cardiovascular disease. Randomized clinical studies with lipid lowering agents suggested that part of the beneficial effect may have been related to reduction in inflammation. More recently, a few studies were designed to directly address the role of anti-inflammatory treatments in reducing risk of atherosclerotic heart disease beyond traditional risk factors. In this article, we review the pathophysiologic contribution of inflammation to atherosclerosis, biomarkers of inflammation and the evidence collected in observational studies regarding the role of chronic inflammation in the development of atherosclerotic heart disease. Finally, we discuss the most recent randomized clinical trials of anti-inflammatory agents directed at stemming atherosclerotic cardiovascular disease.
Assuntos
Anti-Inflamatórios/uso terapêutico , Aterosclerose/tratamento farmacológico , Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Mediadores da Inflamação/antagonistas & inibidores , Inflamação/tratamento farmacológico , Animais , Anti-Inflamatórios/efeitos adversos , Aterosclerose/imunologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Fármacos Cardiovasculares/efeitos adversos , Doenças Cardiovasculares/imunologia , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
The objective of this study was to determine whether sending an information pamphlet to patients scheduled for a PET test two weeks prior to the appointment date significantly reduced patient anxiety and increased patient knowledge about the test. This study was conducted as a randomized controlled trial in which patients were randomly allocated to receive a mailed information pamphlet (intervention) or no mailed pamphlet two weeks prior to the appointment (usual care). The results of this study suggested that sending information pamphlets to patients scheduled for PET scans did not decrease pre-test levels of patient anxiety or result in increased patient knowledge about test preparation and procedures.
Assuntos
Ansiedade/prevenção & controle , Atitude Frente a Saúde , Educação de Pacientes como Assunto/métodos , Materiais de Ensino/normas , Tomografia Computadorizada de Emissão , Idoso , Ansiedade/diagnóstico , Ansiedade/etiologia , Avaliação Educacional , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa em Avaliação de Enfermagem , Folhetos , Escalas de Graduação Psiquiátrica , Tomografia Computadorizada de Emissão/efeitos adversos , Tomografia Computadorizada de Emissão/enfermagem , Tomografia Computadorizada de Emissão/psicologiaRESUMO
OBJECTIVES: The aim of the current analysis was to compare sex differences in the prognostic accuracy of stress myocardial perfusion rubidum-82 (Rb-82) positron emission tomography (PET). BACKGROUND: The diagnostic evaluation of women presenting with suspected cardiac symptoms is challenging with reported reduced accuracy, attenuation artifact, and more recent concerns regarding radiation safety. Stress myocardial perfusion Rb-82 PET is a diagnostic alternative with improved image quality and radiation dosimetry. Currently, the prognostic accuracy of stress Rb-82 PET in women has not been established. METHODS: A total of 6,037 women and men were enrolled in the PET Prognosis Multicenter Registry. Patients were followed for the occurrence of coronary artery disease (CAD) mortality, with a median follow-up of 2.2 years. Cox proportional hazards modeling was used to estimate CAD mortality. The net re-classification improvement index (NRI) was calculated. RESULTS: The 5-year CAD mortality was 3.7% for women and 6.0% for men (p < 0.0001). Unadjusted CAD mortality ranged from 0.9% to 12.9% for women (p < 0.0001) and from 1.5% to 17.4% for men (p < 0.0001) for 0% to ≥15% abnormal myocardium at stress. In multivariable models, the percentage of abnormal stress myocardium was independently predictive of CAD mortality in women and men. An interaction term of sex by the percentage of abnormal stress myocardium was nonsignificant (p = 0.39). The categorical NRI when Rb-82 PET data was added to a clinical risk model was 0.12 for women and 0.17 for men. Only 2 cardiac deaths were reported in women <55 years of age; accordingly the percentage of abnormal myocardium at stress was of borderline significance (p = 0.063), but it was highly significant for women ≥55 years of age (p < 0.0001), with an increased NRI of 0.21 (95% confidence interval: 0.09 to 0.34), including 17% of CAD deaths and 3.9% of CAD survivors that were correctly re-classified in this older female subset. CONCLUSIONS: Stress Rb-82 PET provides significant and clinically meaningful effective risk stratification of women and men, supporting this modality as an alternative to comparative imaging modalities. Rb-82 PET findings were particularly helpful at identifying high-risk, older women.
Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Sistema de Registros , Radioisótopos de Rubídio , Caracteres Sexuais , Idoso , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/patologia , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , América do Norte/epidemiologia , Tomografia por Emissão de Pósitrons , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de RiscoAssuntos
Anomalias dos Vasos Coronários/diagnóstico por imagem , Angiografia Coronária , Circulação Coronária , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Radioisótopos de Rubídio , Tomografia Computadorizada de EmissãoRESUMO
BACKGROUND: Myocardial viability and quantification of regional myocardial blood flow (MBF) are important for the diagnosis of heart disease. Positron emission tomography is the current gold standard for determining myocardial viability, but most positron-emitting perfusion tracers require an on-site cyclotron. Rubidium-82 ((82)Rb) is a myocardial perfusion tracer that is produced using an on-site generator. This study investigates (82)Rb-measured MBF in canine models of stunned and infarcted myocardium compared with selected measurements obtained concurrently using microspheres. METHODS: Myocardial stunning and infarction were created in canines by occluding the left anterior descending for 15 min and 2 h, respectively. Stunning was produced in all animals; six animals were reperfused after the 2 h occlusion, whereas the other six animals remained occluded permanently. Regional MBF was measured in each group during rest and dobutamine stress at acute and chronic (8 weeks postinsult) time points using dynamic (82)Rb perfusion imaging and radioactively labeled microspheres. RESULTS: Average resting MBF with microspheres and Rb was 0.68+/-0.02 versus 0.73+/-0.01 (P<0.001) in nonischemic tissue, and 0.53+/-0.03 versus 0.42+/-0.02 (P<0.001) in the region-at-risk tissue, respectively. Average MBF during stress with microspheres and Rb was 2.78+/-0.15 versus 3.53+/-0.16 (P<0.05) in the nonischemic tissue, and 1.90+/-0.20 versus 2.31+/-0.26 (P = NS) in the region-at-risk tissue, respectively. CONCLUSION: Despite the small significant differences, the dynamic (82)Rb measurements provide estimates of MBF in stunned and acutely and chronically infarcted tissue at rest and during hyperemia that correspond with clinical interpretation.
Assuntos
Circulação Coronária , Microesferas , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/fisiopatologia , Miocárdio Atordoado/diagnóstico por imagem , Miocárdio Atordoado/fisiopatologia , Radioisótopos de Rubídio , Animais , Modelos Animais de Doenças , Cães , Coração/diagnóstico por imagem , Coração/fisiopatologia , Hiperemia/diagnóstico por imagem , Hiperemia/fisiopatologia , Tomografia por Emissão de Pósitrons , DescansoRESUMO
OBJECTIVE: Endothelial dysfunction and decreased nitric oxide bioavailability may explain why therapeutic angiogenesis and cell therapy have mostly failed in humans. Building from previous large animal work, the Phase I Endothelial Modulation in Angiogenic Therapy trial tested the hypothesis that L-arginine, a nitric oxide donor, may be safe and effective in potentiating surgical angiogenesis in humans. METHODS: Patients with surgical triple-vessel coronary disease and a severely diffusely diseased left anterior descending artery were randomized in 2 x 2 factorial fashion to receive ten 200-microg injections of vascular endothelial growth factor-165 plasmid DNA or placebo in the anterior myocardium along the proximal and mid-left anterior descending arteries, plus oral L-arginine supplementation at a dose of 6 g per day or placebo for 3 months. The distal left anterior descending artery and other coronary arteries were grafted. End points included 3-month changes in myocardial perfusion and contractility of the anterior myocardium, using (13)N-ammonia positron emission tomography and echocardiography. Baseline scans were obtained 3 to 7 days postoperatively to delineate treatment effects from the effects of coronary artery bypass grafting. RESULTS: Patient (N = 19) characteristics were equivalent between groups. There was no perioperative or late mortality. Patients who received the combination of vascular endothelial growth factor and L-arginine had improved anterior wall perfusion on positron emission tomography (P = .02), a trend toward smaller perfusion defects (P = .10), and better anterior wall contractility (P = .02, Kruskal-Wallis) at 3 months versus baseline. This was corroborated by a trend toward better disease perception at 3 months versus baseline on the Seattle Angina Questionnaire (score improvement of 47 +/- 35, combination treatment group; P = .1, Kruskal-Wallis). CONCLUSION: To our knowledge, this is the first study to examine concomitant substrate modification in patients undergoing new biosurgical therapies by using vascular endothelial growth factor angiogenesis. The results suggest safety and efficacy. Concomitant endothelial modulation with L-arginine not only has the potential to make angiogenesis effective but also may have implications for cell therapy trials.
Assuntos
Indutores da Angiogênese/administração & dosagem , Arginina/administração & dosagem , Doença da Artéria Coronariana/tratamento farmacológico , Doadores de Óxido Nítrico/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Administração Oral , Idoso , Ponte de Artéria Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Circulação Coronária/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Tomografia por Emissão de Pósitrons , Resultado do TratamentoRESUMO
BACKGROUND: Our objectives were to investigate the accuracy of global and regional left ventricular (LV) function parameters determined from gated fluorine 18 deoxyglucose (FDG) positron emission tomography (PET) and to determine whether this approach complements viability imaging data for tissue characterization. Nongated FDG-PET is a clinical standard for viability imaging, but LV function is often determined with other techniques, which increases patient burden, expenditure, and co-registration errors. Better tissue characterization may be achieved if data were acquired with one test. Methods and results Forty-eight patients with LV dysfunction (including 35 with ejection fraction [EF] =35%) underwent perfusion/FDG imaging with gating of the FDG images and radionuclide angiography (RNA) 6 +/- 6 days apart. Regional function (wall motion/thickening) and viability pattern (normal, mismatch, nontransmural scar, and transmural scar) were determined for 301 segments. Global EFs from FDG-PET (29.3% +/- 11.5%) and RNA (31.1% +/- 10.4%) were well correlated: EF(FDG-PET) = 0.91 x EF(RNA) + 0.91 (r = 0.83, P <.00001). Regional wall motion concordance between PET and RNA with three wall motion scores was 67% with moderate agreement (kappa = 0.50, P <.001). PET viability was also determined for each segment. The relative frequency of normal motion compared with abnormal motion decreased with worsening viability classification. Of the normal segments, 96 of 139 (69%) had reduced wall motion, suggesting repetitively stunned myocardium. Segments classified as normal or mismatch had a higher frequency of normal wall thickening (65% and 52%) than wall motion (31% and 17%). No segments classified as transmural scar exhibited normal wall thickening. CONCLUSION: Gated FDG-PET accurately measures global LV function. Regional function can also be determined with reasonable accuracy. This approach also provides precise co-registration of function with metabolic information and thus improved tissue characterization of the myocardium. Gated FDG-PET has the potential to assist in optimizing management of this patient population.