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1.
Br J Anaesth ; 111 Suppl 1: i96-113, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24335403

RESUMO

The new oral anticoagulants are approved for a variety of clinical syndromes, including the prevention of stroke in atrial fibrillation, acute coronary syndromes, treatment of venous thromboembolism (VTE), and prevention of venous thrombosis after total joint surgery or hip fracture. Published guidelines have differing recommendations on the safe interval between discontinuation of the anticoagulant and performance of neuraxial procedures and between the interventional procedure and redosing of the drug. While two to three half-life intervals might be acceptable in patients who are at high risk for VTE or stroke, an interval of four to six half-lives between discontinuation of the drug and neuraxial injections is probably safer in most patients at low risk of thrombosis. In those with renal disease, the interval should be based on creatinine clearance. After a neuraxial procedure or removal of an epidural catheter, anticoagulants can be resumed within 24-48 h in most patients, but they can be taken sooner in patients who are at higher risk for VTE or stroke, that is, 24 h minus the time to peak effect of the drug. The new antiplatelet drugs prasugrel and ticagrelor should be stopped 7 or 5 days, respectively, before a neuraxial injection and can be restarted 24 h later. In selected situations, laboratory monitoring of the anticoagulant effect is appropriate, and reversal agents are suggested when there is a need to rapidly restore haemostatic function.


Assuntos
Anestesia por Condução , Anticoagulantes/uso terapêutico , Administração Oral , Anticoagulantes/administração & dosagem , Benzimidazóis/uso terapêutico , Dabigatrana , Humanos , Morfolinas/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Pirazóis/uso terapêutico , Piridonas/uso terapêutico , Rivaroxabana , Tiofenos/uso terapêutico , Trombose/prevenção & controle , beta-Alanina/análogos & derivados , beta-Alanina/uso terapêutico
2.
J Thorac Cardiovasc Surg ; 136(1): 73-81, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18603056

RESUMO

OBJECTIVE: Complexity of mitral valve repair for myxomatous disease has led to low adoption. We report initial experience with a new ring designed specifically for myxomatous disease, the Myxo-ETlogix (Edwards Lifesciences LLC, Irvine, Calif). METHODS: From March 15, 2006, through November 19, 2007, 129 patients underwent mitral valve surgery for pure myxomatous disease, and 124 valves (96.1%) were repaired. The Myxo-ETlogix ring was used in 100 cases and the Physio ring (Edwards) in 24. The Myxo-ETlogix design includes a 3-dimensional shape to reduce systolic anterior motion and a larger orifice to accommodate elongated leaflets and decrease need for sliding plasty. Direct mitral valve measurements were made. Sizing was based on A2 height, and choice of ring type was based on unresected leaflet heights. RESULTS: There was no operative mortality or lasting perioperative morbidity. The Myxo-ETlogix group had taller A2, P1, P2, and P3 leaflet segments than the Physio group (P < or = .003). Only 1 sliding plasty was performed for asymmetry in the Myxo-ETlogix group. Predischarge and follow-up echocardiograms (n = 338 in 124 patients) disclosed transient nonobstructive chordal systolic anterior motion in 3 echocardiograms in 3 patients. No patients had 2+ or greater mitral regurgitation. At discharge, 5.7% had 1+ mitral regurgitation; this proportion was 17.3% at last follow-up (mean 6.1 +/- 4.4 months). CONCLUSION: In initial experience with the Myxo-ETlogix ring, nonobstructive systolic anterior motion has been rare and obstructive systolic anterior motion not observed. Ongoing prospective echocardiographic and clinical studies will elucidate the role of this etiology-specific ring.


Assuntos
Próteses Valvulares Cardíacas , Prolapso da Valva Mitral/terapia , Valva Mitral/cirurgia , Idoso , Idoso de 80 Anos ou mais , Ecocardiografia , Feminino , Seguimentos , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Valva Mitral/diagnóstico por imagem , Desenho de Prótese , Ajuste de Prótese , Resultado do Tratamento
3.
Am J Transplant ; 8(7): 1523-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18510630

RESUMO

Patients with obstructive coronary artery disease (CAD) undergoing orthotopic liver transplantation (OLT) are at increased risk of poor outcomes. The accuracy of dobutamine stress echocardiography (DSE) to detect obstructive CAD is not well established in this population. We retrospectively identified patients with end-stage liver disease who underwent both DSE and coronary angiography as part of risk stratification prior to OLT. One hundred and five patients had both DSE and angiography, of whom 14 had known CAD and 27 failed to reach target heart rate during DSE. Among the remaining 64 patients (45 men; average age 61 +/- 8 years) DSE had a low sensitivity (13%), high specificity (85%), low positive predictive value (PPV) (22%) and intermediate negative predictive value (NPV) (75%) for obstructive CAD. DSE as a screening test for obstructive CAD in OLT candidates has a poor sensitivity. The frequent chronotropic incompetence and low sensitivity in patients who achieve target heart rate, even in those with multiple cardiovascular disease risk factors, suggest that alternative or additional methods of risk stratification are necessary.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Ecocardiografia sob Estresse , Transplante de Fígado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade
4.
Heart ; 94(6): 730-6, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18070953

RESUMO

OBJECTIVES: Ejection fraction (EF) and end-systolic volume index (ESVI) are established predictors of outcomes following ST-segment elevation myocardial infarction (STEMI). We sought to assess the relative impact of infarct size, EF and ESVI on clinical outcomes and left ventricular (LV) remodelling. DESIGN: Prospective cohort study. SETTING: Academic hospital in Chicago, USA. PATIENTS: 122 patients with STEMI following acute percutaneous reperfusion. MAIN OUTCOME MEASURES: Death, recurrent myocardial infarction (MI) and heart failure. METHODS: Cardiac magnetic resonance imaging was obtained within 1 week following STEMI in 122 subjects. ESVI, EF and infarct size were tested for the association with outcomes over 2 years in 113 subjects, and a repeat study was obtained 4 months later to assess LV remodelling in 91 subjects. RESULTS: Acute infarct size correlated linearly with the initial ESVI (r = 0.69, p<0.001), end-diastolic volume index (EDVI) (r = 0.42, p<0.001) and EF (r = -0.75, p<0.001). All were independently associated with outcomes (one death, one recurrent MI and 16 heart failure admissions). However, infarct size was the only significant predictor of adverse outcomes (p<0.05) by multivariate analysis. The smallest infarct size tertile had an increased EF (49% (SD 8%) to 53% (6%); p = 0.002) and unchanged EDVI (p = 0.7). In contrast, subjects with the largest infarct tertile also had improved EF (32% (9%) to 36% (11%); p = 0.002) at the expense of a dramatic increase in EDVI (86 (19) to 95 (21) ml/m(2); p = 0.005). CONCLUSIONS: Infarct size, EF and ESVI can predict the development of future cardiac events. Acute infarct size, which is independent of LV stunning and loading, directly relates to LV remodelling and is a stronger predictor of future events than measures of LV systolic performance.


Assuntos
Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/patologia , Disfunção Ventricular Esquerda/fisiopatologia , Remodelação Ventricular/fisiologia , Meios de Contraste , Angiografia Coronária , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Volume Sistólico/fisiologia , Sístole/fisiologia
5.
Clin Pharmacol Ther ; 82(4): 435-40, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17728764

RESUMO

The goal of this experiment was to identify the presence of genetic variants in the adenosine receptor genes and assess their relationship to infarct size in a population of patients with ischemic cardiomyopathy. Adenosine receptors play an important role in protecting the heart during ischemia and in mediating the effects of ischemic preconditioning. We sequenced DNA samples from 273 individuals with ischemic cardiomyopathy and from 203 normal controls to identify the presence of genetic variants in the adenosine receptor genes. Subsequently, we analyzed the relationship between the identified genetic variants and infarct size, left ventricular size, and left ventricular function. Three variants in the 3'-untranslated region of the A(1)-adenosine gene (nt 1689 C/A, nt 2206 Tdel, nt 2683del36) and an informative polymorphism in the coding region of the A3-adenosine gene (nt 1509 A/C I248L) were associated with changes in infarct size. These results suggest that genetic variants in the adenosine receptor genes may predict the heart's response to ischemia or injury and might also influence an individual's response to adenosine therapy.


Assuntos
Cardiomiopatias/complicações , Mutação , Infarto do Miocárdio/genética , Isquemia Miocárdica/complicações , Polimorfismo de Nucleotídeo Único , Receptor A1 de Adenosina/genética , Receptor A3 de Adenosina/genética , Regiões 3' não Traduzidas , Sequência de Bases , Cardiomiopatias/genética , Cardiomiopatias/patologia , Cardiomiopatias/fisiopatologia , Estudos de Casos e Controles , Análise Mutacional de DNA , Frequência do Gene , Predisposição Genética para Doença , Ventrículos do Coração/patologia , Humanos , Dados de Sequência Molecular , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Isquemia Miocárdica/genética , Isquemia Miocárdica/patologia , Isquemia Miocárdica/fisiopatologia , Fenótipo , Receptor A2A de Adenosina/genética , Fatores de Risco , Índice de Gravidade de Doença , Função Ventricular Esquerda/genética
6.
Heart ; 91(6): 806-10, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15894785

RESUMO

OBJECTIVE: To study in a rabbit model the expression of endothelial nitric oxide synthase (eNOS) in association with the development of calcification of the aortic valve, and to assess the effects of atorvastatin on eNOS expression, nitrite concentration, and aortic valve calcification. METHODS: Rabbits (n = 48) were treated for three months: 16, forming a control group, were fed a normal diet; 16 were fed a 0.5% (wt/wt) high cholesterol diet; and 16 were fed a 0.5% (wt/wt) cholesterol diet plus atorvastatin (2.5 mg/kg/day). The aortic valves were examined with eNOS immunostains and western blotting. Cholesterol and high sensitivity C reactive protein (hsCRP) concentrations were determined by standard assays. Serum nitrite concentrations were measured with a nitric oxide analyser. eNOS was localised by electron microscopy and immunogold labelling. Calcification in the aortic valve was evaluated by micro-computed tomography (CT). RESULTS: Cholesterol, hsCRP, and aortic valve calcification were increased in the cholesterol fed compared with control animals. Atorvastatin inhibited calcification in the aortic valve as assessed by micro-CT. eNOS protein concentrations were unchanged in the control and cholesterol groups but increased in the atorvastatin treated group. Serum nitrite concentrations were decreased in the hypercholesterolaemic animals and increased in the group treated with atorvastatin. CONCLUSION: These data provide evidence that chronic experimental hypercholesterolaemia produces bone mineralisation in the aortic valve, which is inhibited by atorvastatin.


Assuntos
Anticolesterolemiantes/uso terapêutico , Valva Aórtica/enzimologia , Calcinose/prevenção & controle , Doenças das Valvas Cardíacas/prevenção & controle , Ácidos Heptanoicos/uso terapêutico , Óxido Nítrico Sintase/metabolismo , Pirróis/uso terapêutico , Animais , Atorvastatina , Western Blotting , Proteína C-Reativa/análise , Colesterol/sangue , Doenças das Valvas Cardíacas/sangue , Doenças das Valvas Cardíacas/enzimologia , Hipercolesterolemia/sangue , Hipercolesterolemia/enzimologia , Hipercolesterolemia/prevenção & controle , Masculino , Óxido Nítrico Sintase Tipo III , Nitritos/sangue , Coelhos , Tomografia Computadorizada por Raios X/métodos
7.
Am J Cardiol ; 88(10): 1103-7, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11703952

RESUMO

To determine predictors of a long-term major adverse cardiac event (MACE) in unselected patients undergoing direct percutaneous coronary intervention (PCI), 274 consecutive patients presenting within 12 hours of ST-segment elevation acute myocardial infarction (AMI) were evaluated. No patient with ST-segment elevation AMI received intravenous thrombolytic drugs. Chest pain to balloon time was 3.8 hours (range 2.5 to 6.9). percutaneous transluminal coronary angioplasty was successful in 95% of patients. Abciximab was administered to 69% of patients, stents were deployed in 53%, and 17% underwent only catheterization. In-hospital events were death (7%), abrupt closure (2%), emergent coronary artery bypass grafting (CABG) (5%), repeat PCI (3%), and recurrent myocardial infarction (1%). In patients undergoing direct PCI (n = 227), the in-hospital event rate was death 5.3%, abrupt closure 2.2%, emergency CABG 0.9%, repeat PCI 3.1%, and repeat myocardial infarction 1.3%. Median time to last follow-up or death was 20 months (range 11 to 34), and to any event, 0.3 months (range 0.03 to 24.0). Postdischarge MACE included death (5%), AMI (4%), repeat PCI (8%), CABG (9%), and stroke (0.7%). Among those undergoing direct PCI (n = 227), 10% died, 3.5% had a repeat AMI, 9% had a repeat PCI, 5% had CABG, and 1% had a stroke at long-term follow-up. At long-term follow-up, 75% were event free. Multivariate predictors were (hazard ratio [95% confidence interval (CI)]): abciximab use 0.6 (95% CI 0.43 to 0.95), Killip class 2.2 (95% CI 1.1 to 4.4), and number of narrowed coronary arteries 1.7 (95% CI 1.4 to 2.2). In this unselected consecutive series of patients presenting with ST-segment elevation AMI, direct PCI was associated with sustained long-term efficacy. Outcomes were predicted by cardiac impairment at presentation and number of narrowed coronary arteries. MACE is not related to device selection but is significantly improved with abciximab.


Assuntos
Angioplastia Coronária com Balão , Infarto do Miocárdio/terapia , Abciximab , Anticorpos Monoclonais/uso terapêutico , Anticoagulantes/uso terapêutico , Aspirina/uso terapêutico , Intervalo Livre de Doença , Feminino , Mortalidade Hospitalar , Humanos , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/mortalidade , Valor Preditivo dos Testes , Stents , Resultado do Tratamento
9.
Am Heart J ; 142(5): 872-80, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11685177

RESUMO

BACKGROUND: Patients with severe myocardial ischemia who are not candidates for percutaneous or surgical revascularization have few therapeutic options. Therapeutic angiogenesis in animal models with use of recombinant human vascular endothelial growth factor (rhVEGF) has resulted in successful revascularization of ischemic myocardium. This was a dose escalation trial designed to determine the safety and tolerability of intracoronary rhVEGF infusions. METHODS AND RESULTS: Patients were eligible if they had stable exertional angina, a significant reversible perfusion defect by stress myocardial perfusion study, and coronary anatomy that was suboptimal for percutaneous coronary intervention or coronary artery bypass grafting. rhVEGF was administered to a total of 15 patients by 2 sequential (eg, right and left) intracoronary infusions, each for 10 minutes, at rates of 0.005 (n = 4), 0.017 (n = 4), 0.050 (n = 4), and 0.167 mg/kg/min (n = 3). Pharmacokinetic sampling and hemodynamic monitoring were performed for 24 hours. Radionuclide myocardial perfusion imaging was performed before treatment and at 30 and 60 days after treatment. Follow-up angiograms were performed on selected patients at 60 days. The maximally tolerated intracardiac dose of rhVEGF was 0.050 mg/kg/min. Minimal hemodynamic changes were seen at 0.0050 mg/kg/min (2% +/- 7% [SD] mean decrease in systolic blood pressure from baseline to nadir systolic blood pressure), whereas at 0.167 mg/kg/min there was a 28% +/- 7% mean decrease from baseline to nadir (136 to 95 mm Hg systolic). Myocardial perfusion imaging was improved in 7 of 14 patients at 60 days. All 7 patients with follow-up angiograms had improvements in the collateral density score. CONCLUSION: rhVEGF appears well tolerated by coronary infusion at rates up to 0.050 mg/kg/min. This study provides the basis for future clinical trials to assess the clinical benefit of therapeutic angiogenesis with rhVEGF.


Assuntos
Doença das Coronárias/tratamento farmacológico , Fatores de Crescimento Endotelial/administração & dosagem , Linfocinas/administração & dosagem , Isoformas de Proteínas/administração & dosagem , Circulação Coronária/efeitos dos fármacos , Fatores de Crescimento Endotelial/farmacologia , Fatores de Crescimento Endotelial/uso terapêutico , Humanos , Linfocinas/farmacologia , Linfocinas/uso terapêutico , Neovascularização Fisiológica/efeitos dos fármacos , Isoformas de Proteínas/farmacologia , Isoformas de Proteínas/uso terapêutico , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
11.
Circulation ; 104(5): 563-9, 2001 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-11479254

RESUMO

BACKGROUND: Hypertension persists in many patients with diabetes mellitus after kidney transplantation. However, the impact of control of diabetes as well as kidney failure on hypertension by combined kidney and pancreas transplantation has not been studied. METHODS AND RESULTS: Between March 1993 and August 1998, 111 patients with type 1 diabetes mellitus underwent successful pancreas transplantation (108 kidney/pancreas transplantation) and another 28 patients with type 1 diabetes mellitus underwent isolated kidney transplantation. Blood pressure measurements and all antihypertensive medications were determined for both groups before transplantation and at 1, 3, 6, and 12 months and at the most recent outpatient evaluation after transplantation. At baseline, the mean blood pressure was 151/88 and 151/83 mm Hg for the kidney/pancreas and isolated kidney transplant patients, respectively. The mean blood pressure decreased to 134/77 mm Hg 1 month after kidney/pancreas transplantation (P<0.001) and decreased further to 126/70 mm Hg (P<0.001) at a mean follow-up of 18 months. This reduction in blood pressure after transplantation occurred despite a decrease in antihypertensive medications and the institution of immunosuppressive agents. At 1 month after kidney/pancreas transplantation, the average number of antihypertensive medications per patient was 0.9+/-1.0, compared with 2.5+/-1.1 before surgery (P<0.001). At 18 months after transplantation, 34% of patients were both normotensive (blood pressure

Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Hipertensão/fisiopatologia , Adulto , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Ciclosporina/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipertensão/tratamento farmacológico , Imunossupressores/uso terapêutico , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Pâncreas/fisiopatologia , Transplante de Pâncreas , Fatores de Tempo
12.
Am Heart J ; 142(1): 167-73, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11431674

RESUMO

BACKGROUND: A reduction in the relative lymphocyte count is a marker of the stress response; however, its prognostic value remains undetermined. The objective of this study was to investigate the predictive value of the relative lymphocyte count for survival in elderly patients with congestive heart failure (CHF). METHODS AND RESULTS: One thousand two hundred seventy-four consecutive patients above the age of 65 years hospitalized with heart disease were enrolled in the CHF Italian Study and followed up for 3 years. Of these, 413 patients were excluded because of factors that could affect the lymphocyte count. Of the remaining 861 patients, 423 (49%) met the criteria for the diagnosis of CHF (mean age 76 +/- 7 years, 51% men), of whom 162 patients (38%) had a relative lymphocyte count < or = 20%. The 3-year all-cause mortality in patients with CHF and a relative lymphocyte count < or = 20% was 64% compared with 40% in patients with a relative lymphocyte count > 20% (P < .0001). The age- and sex-adjusted hazard ratio for death in patients with CHF and low relative lymphocyte count was 1.76 (95% confidence interval 1.34-2.32, P = .0001). After adjustment for baseline differences and variables associated with or known to affect lymphocyte count, the hazard ratio remained significantly different from 1.0 (hazard ratio 1.73, 95% confidence interval 1.21-2.48, P = .0026). CONCLUSION: A low relative lymphocyte count is an independent marker of poor prognosis in elderly patients with CHF. The relative lymphocyte count is a simple, accurate, widely available, and inexpensive marker that can help to identify elderly patients with CHF who are at increased risk for mortality. The pathophysiologic mechanism of this observation remains to be determined.


Assuntos
Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Contagem de Linfócitos , Idoso , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Análise de Sobrevida
13.
Circulation ; 103(23): 2780-3, 2001 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-11401931

RESUMO

BACKGROUND: Mild elevations in creatine kinase-MB (CK-MB) are common after successful percutaneous coronary interventions and are associated with future adverse cardiac events. The mechanism for CK-MB release remains unclear. A new contrast-enhanced MRI technique allows direct visualization of myonecrosis. METHODS AND RESULTS: Fourteen patients without prior infarction underwent cine and contrast-enhanced MRI after successful coronary stenting; 9 patients had procedure-related CK-MB elevation, and 5 did not (negative controls). The mean age of all patients was 61 years, 36% had diabetes, 43% had multivessel coronary artery disease, and all had a normal ejection fraction. Twelve patients (86%) received an intravenous glycoprotein IIb/IIIa inhibitor; none underwent atherectomy, and all had final TIMI 3 flow. Of the 9 patients with CK-MB elevation, 5 had a minor side branch occlusion during stenting, 2 had transient ECG changes, and none developed Q-waves. The median CK-MB was 21 ng/mL (range, 12 to 93 ng/mL), which is 2.3x the upper limit of normal. Contrast-enhanced MRI demonstrated discrete regions of hyperenhancement within the target vessel perfusion territory in all 9 patients. Only one developed a new wall motion abnormality. The median estimated mass of myonecrosis was 2.0 g (range, 0.7 to 12.2 g), or 1.5% of left ventricular mass (range, 0.4% to 6.0%). Hyperenhancement persisted in 5 of the 6 who underwent a repeat MRI at 3 to 12 months. No control patient had hyperenhancement. CONCLUSIONS: Contrast-enhanced MRI provides an anatomical correlate to biochemical evidence of procedure-related myocardial injury, despite the lack of ECG changes or wall motion abnormalities. Mild elevation of CK-MB after percutaneous coronary intervention is the result of discrete microinfarction.


Assuntos
Implante de Prótese Vascular/efeitos adversos , Creatina Quinase/sangue , Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Adulto , Idoso , Angiografia Coronária , Creatina Quinase Forma MB , Ecocardiografia , Eletrocardiografia , Humanos , Aumento da Imagem , Isoenzimas/sangue , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Necrose , Valor Preditivo dos Testes , Stents , Troponina I/sangue
15.
Am J Cardiol ; 87(7): 874-80, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11274943

RESUMO

The assessment of left ventricular electromechanical activity using a novel, nonfluoroscopic 3-dimensional mapping system demonstrates considerable differences in electrical and mechanical activities within regions of myocardial infarction or ischemia. We sought to determine whether these changes correlate with indexes of myocardial perfusion, viability, or ischemia. A 12-segment comparative analysis was performed in 61 patients (45 men, 61 +/- 12 years old) with class III to IV angina, having reversible and/or fixed myocardial perfusion defects on single-photon emission computed tomographic perfusion imaging. A dual-isotope protocol was used, consisting of rest and 4-hour redistribution thallium images followed by adenosine technetium-99m sestamibi imaging. Average rest endocardial unipolar voltage (UpV) and local shortening (LS) mapping values were compared with visually derived perfusion scores. There was gradual and proportional reduction in regional UpV and LS in relation to thallium-201 uptake score at rest (p = 0.0001 and p = 0.0002, respectively) and redistribution studies (p = 0.0001 and p = 0.003, respectively). UpV > or = 7.4 mV and LS > or = 5.0% had a sensitivity of 78% and 65%, respectively, with a specificity of 68% and 67% for detecting viable myocardium. UpV values of 12.3 and 5.4 mV had 90% specificity and sensitivity, respectively, to predict viable tissue. UpV, but not LS, values differentiated between normal segments and those with adenosine-induced severe perfusion defects (11.8 +/- 5.3 vs 8.8 +/- 4.1 mV, p = 0.005). Catheter-based left ventricular assessment of electromechanical activity correlates with the degree of single-photon emission computed tomographic perfusion abnormality and can identify myocardial viability with a greater accuracy than myocardial ischemia.


Assuntos
Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/fisiopatologia , Adenosina , Adulto , Idoso , Angina Pectoris/diagnóstico por imagem , Angina Pectoris/fisiopatologia , Estudos de Coortes , Eletrofisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Radiografia , Sensibilidade e Especificidade , Tecnécio Tc 99m Sestamibi , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único , Estados Unidos , Disfunção Ventricular Esquerda/diagnóstico por imagem
16.
Lancet ; 357(9249): 21-8, 2001 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-11197356

RESUMO

BACKGROUND: A technical advance in contrast-enhanced magnetic resonance imaging (MRI) has significantly improved image quality. We investigated whether healed myocardial infarction can be visualised as hyperenhanced regions with this new technique, and whether assessment of the transmural extent of infarction yields new physiological data. METHODS: 82 MRI examinations were carried out in three groups: patients with healed myocardial infarction; patients with non-ischaemic cardiomyopathy; and healthy volunteers. Patients with healed myocardial infarction were prospectively enrolled after enyzmatically proven necrosis and imaged 3 months (SD 1) or 14 months (7) later. The MRI procedure used a segmented inversion-recovery gradient-echo sequence after gadolinium administration. Findings were compared with those of coronary angiography, electrocardiography, cine MRI, and creatine kinase measurements. FINDINGS: 29 (91%) of 32 patients with infarcts imaged at 3 months (13 non-Q-wave) and all of 19 imaged at 14 months (eight non-Q-wave) showed hyperenhancement. In patients in whom the infarct-related-artery was identified by angiography, 24 of 25 imaged at 3 months and all of 14 imaged at 14 months had hyperenhancement in the appropriate territory. None of the 20 patients with non-ischaemic cardiomyopathy or the 11 healthy volunteers showed hyperenhancement. Irrespective of the presence or absence of Q waves, the majority of patients with hyperenhancement had only non-transmural involvement. Normal left-ventricular contraction was shown in seven patients examined at 3 months and three examined at 14 months, but in these cases hyperenhancement was limited to the subendocardium. INTERPRETATION: The presence, location, and transmural extent of healed Q-wave and non-Q-wave myocardial infarction can be accurately determined by contrast-enhanced MRI.


Assuntos
Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio/patologia , Miocárdio/patologia , Adulto , Cardiomiopatia Dilatada/patologia , Meios de Contraste , Creatina Quinase/metabolismo , Eletrocardiografia , Feminino , Gadolínio , Compostos Heterocíclicos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Compostos Organometálicos , Fatores de Tempo
17.
N Engl J Med ; 343(20): 1445-53, 2000 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11078769

RESUMO

BACKGROUND: Recent studies indicate that magnetic resonance imaging (MRI) after the administration of contrast material can be used to distinguish between reversible and irreversible myocardial ischemic injury regardless of the extent of wall motion or the age of the infarct. We hypothesized that the results of contrast-enhanced MRI can be used to predict whether regions of abnormal ventricular contraction will improve after revascularization in patients with coronary artery disease. METHODS: Gadolinium-enhanced MRI was performed in 50 patients with ventricular dysfunction before they underwent surgical or percutaneous revascularization. The transmural extent of hyperenhanced regions was postulated to represent the transmural extent of nonviable myocardium. The extent of regional contractility at the same locations was determined by cine MRI before and after revascularization in 41 patients. RESULTS: Contrast-enhanced MRI showed hyperenhancement of myocardial tissue in 40 of 50 patients before revascularization. In all patients with hyperenhancement the difference in image intensity between hyperenhanced regions and regions without hyperenhancement was more than 6 SD. Before revascularization, 804 of the 2093 myocardial segments analyzed (38 percent) had abnormal contractility, and 694 segments (33 percent) had some areas of hyperenhancement. In an analysis of all 804 dysfunctional segments, the likelihood of improvement in regional contractility after revascularization decreased progressively as the transmural extent of hyperenhancement before revascularization increased (P<0.001). For instance, contractility increased in 256 of 329 segments (78 percent) with no hyperenhancement before revascularization, but in only 1 of 58 segments with hyperenhancement of more than 75 percent of tissue. The percentage of the left ventricle that was both dysfunctional and not hyperenhanced before revascularization was strongly related to the degree of improvement in the global mean wall-motion score (P<0.001) and the ejection fraction (P<0.001) after revascularization. CONCLUSIONS: Reversible myocardial dysfunction can be identified by contrast-enhanced MRI before coronary revascularization.


Assuntos
Doença das Coronárias/patologia , Imagem Cinética por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico , Miocárdio/patologia , Disfunção Ventricular Esquerda/diagnóstico , Meios de Contraste , Doença das Coronárias/fisiopatologia , Doença das Coronárias/terapia , Feminino , Gadolínio , Gadolínio DTPA , Ventrículos do Coração/patologia , Compostos Heterocíclicos , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Revascularização Miocárdica , Compostos Organometálicos , Prognóstico , Estudos Prospectivos , Volume Sistólico , Disfunção Ventricular Esquerda/fisiopatologia
18.
Echocardiography ; 17(6 Pt 1): 547-54, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11000589

RESUMO

The objective of this article was to determine whether the presence of left ventricular apical thrombus is a marker of nonviable myocardium. Reduced coronary blood flow secondary to atherosclerosis may result in chronic reversible left ventricular wall-motion abnormalities. Severe regional abnormalities also predispose to formation of left ventricular thrombus. The relationship between left ventricular apical thrombus and myocardial viability has not been previously described. Eighty patients with coronary artery disease and chronic left ventricular dysfunction were studied by dobutamine stress echocardiography. Left ventricular apical thrombus was identified using echocardiographic criteria. Wall-motion analysis was performed using a standard 16-segment model and ejection fraction was calculated. As a result, 48 patients (60%) had definite or highly suspicious findings for left ventricular thrombus (group 1), and 32 patients (40%) had no thrombus (group 2). Group 1 had significantly higher composite (54.0 +/- 5.8 vs 43.3 +/- 6.4) and apical (6.0 +/- 2.7 vs 12.4 +/- 3.4) wall-motion scores compared to those in group 2 (P = 0.01). Thirty-two patients (67%) in group 1 demonstrated no contractile reserve in the apical segments, consistent with lack of viability, versus eight patients (25%) in group 2 (P = 0.0003). The number of viable apical segments per patient was significantly less in group 1 (0.7 +/- 1.2) versus group 2 (1.8 +/- 1.3) (P = 0.01). Left ventricular apical thrombus is more likely to be present when there is absence of myocardial viability in the corresponding segments.


Assuntos
Ecocardiografia , Cardiopatias/diagnóstico por imagem , Trombose/diagnóstico por imagem , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Doença das Coronárias/complicações , Dobutamina , Teste de Esforço , Feminino , Cardiopatias/etiologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Probabilidade , Medição de Risco , Volume Sistólico , Trombose/etiologia , Disfunção Ventricular Esquerda/etiologia
19.
Circulation ; 102(11): E73-86, 2000 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-10982554

RESUMO

The rapid development of angiogenic growth factor therapy for patients with advanced ischemic heart disease over the last 5 years offers hope of a new treatment strategy based on generation of new blood supply in the diseased heart. However, as the field of therapeutic coronary angiogenesis is maturing from basic and preclinical investigations to clinical trials, many new and presently unresolved issues are coming into focus. These include in-depth understanding of the biology of angiogenesis, selection of appropriate patient populations for clinical trials, choice of therapeutic end points and means of their assessment, choice of therapeutic strategy (gene versus protein delivery), route of administration, and the side effect profile. The present article presents a summary statement of a panel of experts actively working in the field, convened by the Angiogenesis Foundation and the Angiogenesis Research Center during the 72nd meeting of the American Heart Association to define and achieve a consensus on the challenges facing development of therapeutic angiogenesis for coronary disease.


Assuntos
Ensaios Clínicos como Assunto , Vasos Coronários , Cardiopatias/terapia , Neovascularização Fisiológica , Indutores da Angiogênese/efeitos adversos , Indutores da Angiogênese/genética , Indutores da Angiogênese/uso terapêutico , Animais , Angiografia Coronária , Fatores de Crescimento Endotelial/efeitos adversos , Fatores de Crescimento Endotelial/genética , Fatores de Crescimento Endotelial/uso terapêutico , Fator 2 de Crescimento de Fibroblastos/efeitos adversos , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Terapia Genética/efeitos adversos , Cardiopatias/diagnóstico por imagem , Humanos , Linfocinas/efeitos adversos , Linfocinas/genética , Linfocinas/uso terapêutico , Imageamento por Ressonância Magnética , Seleção de Pacientes , Tomografia Computadorizada de Emissão , Tomografia Computadorizada de Emissão de Fóton Único , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
20.
Circulation ; 102(10): 1120-5, 2000 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-10973840

RESUMO

BACKGROUND: Direct myocardial revascularization (DMR) has been examined as an alternative treatment for patients with chronic refractory myocardial ischemic syndromes who are not candidates for conventional coronary revascularization. Methods and Results-We used left ventricular electromagnetic guidance in 77 patients with chronic refractory angina (56 men, mean age 61+/-11 years, ejection fraction 0.48+/-0.11) to perform percutaneous DMR with an Ho:YAG laser at 2 J/pulse. Procedural success (laser channels placed in prespecified target zones) was achieved in 76 of 77 patients with an average of 26+/-10 channels (range 11 to 50 channels). The rate of major in-hospital cardiac adverse events was 2.6%, with no deaths or emergency operations, 1 patient with postprocedural pericardiocentesis, and 1 patient with minor embolic stroke. The rate of out-of-hospital adverse cardiac events (up to 6 months) was 2.6%, with 1 patient with myocardial infarction and 1 patient with stroke. Exercise duration after DMR increased from 387+/-179 to 454+/-166 seconds at 1 month and to 479+/-161 seconds at 6 months (P=0.0001). The time to onset of angina increased from 293+/-167 to 377+/-176 seconds at 1 month and to 414+/-169 seconds at 6 months (P=0.0001). Importantly, the time to ST-segment depression (>/=1 mm) also increased from 327+/-178 to 400+/-172 seconds at 1 month and to 436+/-175 seconds at 6 months (P=0.001). Angina (Canadian Cardiovascular Society classification) improved from 3.3+/-0.5 to 2.0+/-1.2 at 6 months (P<0.001). Nuclear perfusion imaging studies with a dual-isotope technique, however, showed no significant improvements at 1 or 6 months. CONCLUSIONS: Percutaneous DMR guided by left ventricular mapping is feasible and safe and reveals improved angina and prolonged exercise duration for up to a 6-month follow-up.


Assuntos
Mapeamento Potencial de Superfície Corporal/métodos , Coração/diagnóstico por imagem , Terapia a Laser/métodos , Revascularização Miocárdica/métodos , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas Biossensoriais , Doença Crônica , Eletrocardiografia , Teste de Esforço , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/cirurgia , Cintilografia
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