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1.
Catheter Cardiovasc Interv ; 99(3): 772-776, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34551189

RESUMO

OBJECTIVES: To demonstrate the feasibility and safety of performing elective percutaneous coronary intervention (PCI) during contrast reaction producing severe hypotension. BACKGROUND: The development of profound hypotension due to a contrast reaction requires emergency treatment and usually signals procedure termination. METHODS AND RESULTS: We report successful completion of planned PCI with blood pressure support with vasopressors during contrast-induced hypotension in nine procedures in three patients with previously known contrast reaction causing hypotension. CONCLUSIONS: This case series provides support for the feasibility and safety of performing successful planned PCI under blood pressure support in patients with contrast reaction causing severe hypotension. A management approach for considering intervention in the setting of contrast-induced hypotension is provided.


Assuntos
Hipotensão Controlada , Intervenção Coronária Percutânea , Procedimentos Cirúrgicos Eletivos , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Resultado do Tratamento
3.
J Invasive Cardiol ; 34(2): E117-E123, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35058375

RESUMO

OBJECTIVE: In this study, we aimed to describe the immediate and long-term vascular effects of OAS in patients with peripheral arterial disease (PAD) and moderate to severely calcified lesions. BACKGROUND: Debulking the calcified atherosclerotic plaque with the orbital atherectomy system (OAS) can potentially enhance vessel compliance and increase the chance of reaching a desirable angioplasty result. METHODS: A total of 7 patients were evaluated both at baseline and at 6-month follow-up. Following a diagnostic peripheral angiogram, patients with significant SFA disease had a baseline intravascular optical coherence tomography (IV-OCT) and the lesion was treated with OAS. Repeat IV-OCT was performed after atherectomy and after drug-coated balloon, if used. Patients were also evaluated with angiography and IV-OCT imaging at their 6-month follow-up. RESULTS: The majority of tissue removed was fibrous tissue. During follow-up, luminal volume increased for 4 of the 7 patients from baseline to 6-month follow-up and decreased in 3 patients. On average there was a 6% increase of luminal volume (P<.01 compared with baseline). A recent virtual histology algorithm was used for automatic classification of IV-OCT images unaided by any reader. The algorithm used convolutional neural networks to identify regions as either calcium, fibrous, or lipid plaque, and it agreed with an expert reader 82% of the time. CONCLUSION: To the best of our knowledge, the current report is the first to describe vascular effects of OAS in medial calcified lesions immediately after and at follow-up using IV-OCT in patients with severe PAD.


Assuntos
Aterectomia Coronária , Doença da Artéria Coronariana , Doença Arterial Periférica , Placa Aterosclerótica , Calcificação Vascular , Aterectomia/métodos , Aterectomia Coronária/efeitos adversos , Doença da Artéria Coronariana/terapia , Humanos , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/cirurgia , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/cirurgia , Fatores de Tempo , Resultado do Tratamento , Calcificação Vascular/diagnóstico , Calcificação Vascular/cirurgia
4.
Am J Physiol Heart Circ Physiol ; 298(2): H524-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19940080

RESUMO

Human studies of coronary circulation are limited because of methodological issues. Recently, a noninvasive transthoracic duplex ultrasound (TTD) technique has emerged as an important tool to measure coronary blood flow velocity (CBV) in conscious humans. We employed two protocols to determine whether noninvasive "native" coronary artery velocity responses to constrictor or dilator stimuli assessed by TTD provide reliable data. In the first protocol, coronary vascular resistance (CVR = diastolic blood pressure/CBV) responses to static handgrip were examined in the left internal mammary artery (LIMA) and native left anterior descending artery (LAD) into which the graft was inserted (patient age 63 +/- 3 years). Our prior report documented increased CVR in the LIMA graft during static handgrip (Momen et al., J Appl Physiol 102: 735-739, 2007). We hypothesized that the magnitude of increases in CVR during handgrip would be similar in the LIMA graft and LAD in the same individual. Percent increases in CVR were similar in the LIMA and distal native LAD (27 +/- 4% vs. 28 +/- 6%). In the second protocol, we studied six patients (age 61 +/- 3 years) who underwent cardiac catheterization of the LAD. We compared coronary vasodilator responses to intravenous adenosine infusion (0.14 mg.kg(-1).min(-1)) obtained by intracoronary Doppler guidewire technique and TTD on separate studies. The relative increases in CBV with adenosine obtained by intracoronary Doppler guidewire and TTD were similar (62 +/- 10% vs. 65 +/- 12%). Noninvasive TTD provides reliable human coronary circulatory constrictor and dilator data.


Assuntos
Vasos Coronários/diagnóstico por imagem , Vasos Coronários/fisiologia , Ecocardiografia , Resistência Vascular/fisiologia , Vasoconstrição/fisiologia , Vasodilatação/fisiologia , Adenosina/farmacologia , Idoso , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Cateterismo Cardíaco , Ponte de Artéria Coronária , Feminino , Força da Mão/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Artéria Torácica Interna/diagnóstico por imagem , Artéria Torácica Interna/fisiologia , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Resistência Vascular/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
5.
Cardiovasc Revasc Med ; 21(1): 101-107, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31395436

RESUMO

PURPOSE: Zilver PTX nitinol self-expanding drug-eluting stent with paclitaxel coating is effective for treatment of superficial femoral artery (SFA) disease. However, as with any stent, it induces a measure of vascular inflammatory response. The current clinical trial (NCT02734836) aimed to assess vascular patency, remodeling, and inflammatory markers with intravascular optical coherence tomography (OCT) in patients with SFA disease treated with Zilver PTX stents. METHODS: Serial OCT examinations were performed in 13 patients at baseline and 12-month follow-up. Variables evaluated included neointimal area, luminal narrowing, thrombus area, stent expansion as well as measures of inflammation including, peri-strut low-intensity area (PLIA), macrophage arc, neovascularization, stent strut apposition and coverage. RESULTS: Percentage of malapposed struts decreased from 10.3 ±â€¯7.9% post-intervention to 1.1 ±â€¯2.2% at 12-month follow-up, but one patient showed late-acquired stent malapposition (LASM). The percent of uncovered struts at follow-up was 3.0 ±â€¯4.5%. Average expansion of stent cross-sectional area from baseline to follow-up was 35 ±â€¯19%. The average neointimal area was 7.8 ±â€¯3.8 mm2. Maximal luminal narrowing was 61.1 ±â€¯25.0%, and average luminal narrowing was 35.4 ±â€¯18.2%. Average peri-strut low-intensity area (PLIA) per strut was 0.017 ±â€¯0.018 mm2. Average number of neovessels per mm of stent was 0.138 ±â€¯0.181. Average macrophage angle per frame at follow-up was 7 ±â€¯11°. Average thrombus area at follow-up was 0.0093 ±â€¯0.0184 mm2. CONCLUSION: At 12-month follow-up, OCT analysis of Zilver PTX stent shows outward remodeling and minimal neointimal growth, but evidence of inflammation including PLIA, neovessels, thrombus and macrophages. SUMMARY: Thirteen patients with PAD had paclitaxel-coated stents implanted in their SFAs and were then imaged with OCT at baseline and 12-month follow-up. OCT proxy metrics of inflammation were quantified.


Assuntos
Angioplastia com Balão/instrumentação , Fármacos Cardiovasculares/administração & dosagem , Stents Farmacológicos , Artéria Femoral/diagnóstico por imagem , Inflamação/diagnóstico por imagem , Paclitaxel/administração & dosagem , Doença Arterial Periférica/terapia , Stents Metálicos Autoexpansíveis , Tomografia de Coerência Óptica , Grau de Desobstrução Vascular , Idoso , Idoso de 80 Anos ou mais , Ligas , Angioplastia com Balão/efeitos adversos , Fármacos Cardiovasculares/efeitos adversos , Feminino , Artéria Femoral/fisiopatologia , Humanos , Inflamação/etiologia , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Neointima , Paclitaxel/efeitos adversos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Valor Preditivo dos Testes , Estudos Prospectivos , Desenho de Prótese , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Remodelação Vascular
6.
Cardiovasc Revasc Med ; 19(6S): 7-11, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29937383

RESUMO

BACKGROUND AND PURPOSE: Transradial percutaneous coronary intervention (TR-PCI) has been increasingly popular over the last decade in the US. Previous studies have shown that same-day (SD) discharge after elective PCI is as safe as overnight (ON) observation. Our study was performed to assess the clinical and financial impact of early discharge in patients undergoing TR-PCI. METHODS: This is a single center registry of patients undergoing elective TR-PCI. Timing of discharge was determined by the treating physician. (Groups: Same Day Discharge -SD-; Overnight Stay -ON-). Demographic data, procedural characteristics and adverse outcomes were recorded. Outcomes included 30 day-MACE and procedure- related complications, as well as total operative costs in patients from both groups. Propensity score matching for patient demographics, coronary symptoms and procedure indicators was used to compare both groups. RESULTS: The entire cohort included 852 patients (429 in SD group and 423 in ON group) and the propensity score matched groups of 245 patients in the SD group and 245 patients in the ON group. The two groups had no significant baseline clinical differences, and had similar clinical outcomes. Specifically, no significant difference was noted in procedural complications (3.7% vs 2.5%, p = 0.43), re-hospitalization (4.1% vs 4.1%, p = 0.92), re-intervention (2.5% vs 2.1%, p = 0.77), myocardial infarction (0% vs 0.08%, p = 0.15), stroke (0% vs 0%, p = 1.0) and all-cause mortality (0% vs 0%, p = 1.0). SD Group patients had a significant lower procedure-related cost compared to overnight stay patients ($3,346.45 vs $4,681.99, p < 0.0001) and lower 30-day post procedure-associated cumulative costs/total operating costs ($4,493.22 vs $7,112.21, p < 0.0001). CONCLUSION: In elective patients undergoing low risk TR-PCI, same-day discharge seems to be a safe and feasible clinical practice, with significant potential savings to the US healthcare system.


Assuntos
Cateterismo Cardíaco/métodos , Cateterismo Periférico/métodos , Doença da Artéria Coronariana/cirurgia , Tempo de Internação , Alta do Paciente , Intervenção Coronária Percutânea/métodos , Artéria Radial , Idoso , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/economia , Cateterismo Periférico/efeitos adversos , Cateterismo Periférico/economia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/economia , Redução de Custos , Análise Custo-Benefício , Estudos de Viabilidade , Feminino , Custos Hospitalares , Humanos , Tempo de Internação/economia , Masculino , Pessoa de Meia-Idade , Alta do Paciente/economia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/economia , Pontuação de Propensão , Punções , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
7.
Cardiovasc Revasc Med ; 19(7 Pt A): 778-784, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29550045

RESUMO

PURPOSE: To compare OCT identified white thrombus decline, neointimal hyperplasia and clinical outcomes of patients treated with ticagrelor plus aspirin with those patients treated with clopidogrel plus aspirin after peripheral interventions. BACKGROUND: Ticagrelor is a potent platelet inhibitor. In patients with coronary artery disease, ticagrelor and aspirin demonstrated reduced rates of stent thrombosis, compared to aspirin and clopidogrel. The clinical importance of potent antiplatelet inhibition after peripheral endovascular interventions is unknown. METHODS: We enrolled 18 patients with superficial femoral artery disease and the presence of OCT-detected clot post-stent placement. Patients were randomized to 75 mg clopidogrel once daily for 1 month vs. 90 mg ticagrelor twice daily for 6 months, both in addition to 81 mg aspirin for 6 months. Clot volumes, ankle-brachial index (ABI), 6-minute walk test, and Rutherford classification were measured at baseline and 6-month follow-up. Neointimal hyperplasia and neovascularization were calculated at 6-month follow-up. RESULTS: N = 11 patients were enrolled in the clopidogrel group and N = 7 in the ticagrelor group. There was a significantly greater decrease in white thrombus in the ticagrelor group (median volume/stent length (0.067 vs 0.014 mm3/mm, p = 0.05)). No differences were found in % neointima (0.412 vs 0.536 mm3/mm, p = 0.44) and neovascularization (28 vs 44, p = 0.16). ABI and Rutherford classification were improved significantly after 6 months in the clopidogrel group, with no difference between groups at 6 months in ABI or Rutherford. CONCLUSION: In symptomatic patients with PAD, ticagrelor showed significant improvement relative to clopidogrel with respect to white thrombus burden decline.


Assuntos
Aspirina/uso terapêutico , Clopidogrel/uso terapêutico , Procedimentos Endovasculares , Artéria Femoral , Doença Arterial Periférica/terapia , Inibidores da Agregação Plaquetária/uso terapêutico , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Trombose/tratamento farmacológico , Ticagrelor/uso terapêutico , Tomografia de Coerência Óptica , Idoso , Índice Tornozelo-Braço , Aspirina/efeitos adversos , Clopidogrel/efeitos adversos , Quimioterapia Combinada , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Europa (Continente) , Feminino , Artéria Femoral/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Neointima , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Inibidores da Agregação Plaquetária/efeitos adversos , Valor Preditivo dos Testes , Estudos Prospectivos , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Recuperação de Função Fisiológica , Stents , Trombose/diagnóstico por imagem , Trombose/etiologia , Trombose/fisiopatologia , Ticagrelor/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Teste de Caminhada
8.
Cardiovasc Revasc Med ; 17(7): 463-467, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27477305

RESUMO

BACKGROUND: Long-term patency rates for percutaneous peripheral arterial interventions are suboptimal. Optical coherence tomography (OCT) guided atherectomy may yield superior patency by optimizing plaque removal while preserving the tunica media and adventitia. METHODS: The VISION study is a multicenter prospective study of patients with peripheral arterial disease undergoing OCT guided atherectomy with the Pantheris™ device. In 11 patients enrolled in a single center, we report procedural and clinical outcomes, at 30days and 6months. RESULTS: The mean age was 63±11years and 73% (n=8) were men. The target lesion was in the superficial femoral artery in 82% (n=9) of the patients. Mean stenosis severity was 87%±10% and mean lesion length was 39±31mm. Procedural success was observed in all patients with no device related complications. Mean post-atherectomy stenosis was 18%±15%. Almost all excised tissue consisted of intimal plaque (94%). At 30days, significant improvements in Rutherford class, VascuQoL scores and ABI were observed, 0.9±0.8 vs. 3.1±0.7 (p=0.01), 4.9±1.9 vs. 3.6±1.5 (p=0.03) and 1.04±0.19 vs. 0.80±0.19 (p<0.01) respectively. At 6months, there were significant improvements in Rutherford class (1.0±1.0 vs. 3.1±0.7, p=0.01) and ABI (0.93±0.19 versus 0.80±0.19, p=0.02) but not in VascuQoL scores (3.7±1.4 versus 3.6±1.5, p=0.48). Target lesion revascularization occurred in 18% (n=2) of the patients. CONCLUSION: OCT guided atherectomy resulted in high procedural success, no device related complications and encouraging results up to 6months. Histological analysis suggested little injury to the media and adventitia. Larger studies are needed to confirm the efficacy of this approach.


Assuntos
Aterectomia/métodos , Artéria Femoral/diagnóstico por imagem , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Tomografia de Coerência Óptica , Idoso , Angiografia , Aterectomia/efeitos adversos , Aterectomia/instrumentação , Constrição Patológica , Desenho de Equipamento , Feminino , Artéria Femoral/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/fisiopatologia , Placa Aterosclerótica , Valor Preditivo dos Testes , Estudos Prospectivos , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
9.
Rev Port Cardiol ; 34(9): 555.e1-4, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26298105

RESUMO

Approximately 60,000-100,000 Americans die from deep venous thrombosis or pulmonary embolism annually, while the overall estimate of individuals affected is 30,000-600,000. Inferior vena cava (IVC) filter placement has emerged as a break-through endovascular technique which has gained increasing acceptance and has probably saved thousands of lives by preventing fatal thromboembolic events. However, in the absence of a national IVC filter registry an accurate estimate of device complications is currently unavailable. We present a case of symptomatic IVC syndrome due to IVC interruption in a patient with a non-retrievable IVC filter. This patient was initially managed with balloon angioplasty and mechanical thrombectomy with suboptimal results and subsequently with stent placement through the IVC filter.


Assuntos
Procedimentos Endovasculares , Complicações Pós-Operatórias/cirurgia , Doenças Vasculares/cirurgia , Filtros de Veia Cava , Veia Cava Inferior , Feminino , Humanos , Pessoa de Meia-Idade , Síndrome
10.
Cardiovasc Revasc Med ; 16(6): 373-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25753654

RESUMO

Directional atherectomy (DA) is one of the most commonly used modalities for the treatment of obstructive femoropopliteal peripheral arterial disease (PAD), especially in patients with large and calcified atherosclerotic plaques. The effect of directional atherectomy to the vascular wall compared to balloon angioplasty by optical coherence tomography (OCT) has not been previously described. We present the first case of OCT after directional atherectomy with SilverHawk followed by angiosculpt balloon angioplasty.


Assuntos
Angioplastia com Balão , Arteriopatias Oclusivas/terapia , Aterectomia , Artéria Femoral/cirurgia , Tomografia de Coerência Óptica , Idoso , Arteriopatias Oclusivas/cirurgia , Humanos , Masculino , Resultado do Tratamento
11.
Cardiovasc Revasc Med ; 15(1): 43-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24444474

RESUMO

Acute limb ischemia due to bypass thrombotic occlusion may occur in patients with poor collateral circulation. It constitutes a medical emergency with increased morbidity, mortality and risk for limb amputation. Although the management of acute limb ischemia due to native artery occlusion is well studied, the optimal approach of acute bypass graft failure resulting in acute limb ischemia is uncertain. We present a case of acute limb ischemia in a patient with femoro-femoral and femoro-popliteal graft who presented with acute limb ischemia due to acute thrombotic occlusion of his femoro-popliteal graft. The patient was successfully managed with ultrasound-enhanced catheter-directed thrombolysis using the EkoSonic® endovascular system with excellent clinical and angiographic results. To our knowledge this is the first published report of the use of the EkoSonic® system for this indication.


Assuntos
Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/instrumentação , Artéria Femoral/cirurgia , Oclusão de Enxerto Vascular/terapia , Doença Arterial Periférica/cirurgia , Artéria Poplítea/cirurgia , Terapia Trombolítica/instrumentação , Trombose/terapia , Terapia por Ultrassom/instrumentação , Dispositivos de Acesso Vascular , Doença Aguda , Desenho de Equipamento , Artéria Femoral/diagnóstico por imagem , Fibrinolíticos/administração & dosagem , Oclusão de Enxerto Vascular/diagnóstico , Oclusão de Enxerto Vascular/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico , Artéria Poplítea/diagnóstico por imagem , Radiografia , Trombose/diagnóstico , Trombose/etiologia , Ativador de Plasminogênio Tecidual/administração & dosagem , Resultado do Tratamento
12.
Cardiovasc Revasc Med ; 15(1): 46-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24157312

RESUMO

Peripheral arterial disease (PAD) is a growing clinical condition affecting more than 10 million patients in the United States and it is responsible for more than 120,000 amputations annually. The presence of chronic total occlusions (CTO) increases the complexity of endovascular procedures and open surgery may often be the preferred approach. Despite the optimization of the CTO devices and technique, percutaneous CTO revascularization remains a challenging procedure even for experienced operators with important complication rates. The Ocelot(TM) system is a novel CTO device to use real-time optical coherence tomography (OCT) imaging guidance for the recanalization of peripheral CTOs. We review the mechanism of the Ocelot system, the initial results from the multi-center Connect-II trial and two cases of Ocelot-assisted CTO recanalization.


Assuntos
Procedimentos Endovasculares/instrumentação , Extremidade Inferior/irrigação sanguínea , Doença Arterial Periférica/terapia , Dispositivos de Acesso Vascular , Idoso , Doença Crônica , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico , Stents , Tomografia de Coerência Óptica , Resultado do Tratamento
13.
J Invasive Cardiol ; 26(5): 220-3, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24791721

RESUMO

Superficial femoral artery (SFA) disease accounts for approximately 40% of the symptomatic peripheral arterial disease and remains a common cause of critical limb ischemia and lower-extremity amputation. Optical coherence tomography (OCT) has been extensively studied in the coronary circulation; however, its use in the peripheral arterial circulation is scarce. We present two cases of OCT use as an ancillary imaging tool during SFA endovascular interventions.


Assuntos
Arteriopatias Oclusivas/patologia , Artéria Femoral/patologia , Doença Arterial Periférica/patologia , Tomografia Óptica , Angiografia , Angioplastia com Balão , Arteriopatias Oclusivas/diagnóstico por imagem , Circulação Sanguínea , Feminino , Artéria Femoral/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Stents , Resultado do Tratamento
16.
Am J Physiol Heart Circ Physiol ; 293(1): H103-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17369474

RESUMO

Patients with diabetes mellitus exhibit postprandial hyperglycemia, systemic oxidative stress, impaired endothelium-dependent, nitric oxide (NO)-mediated coronary artery dilatation, and an increased incidence of coronary events. Whether hyperglycemia causally mediates these associations is unknown. To test the hypothesis that postprandial hyperglycemia acutely impairs coronary endothelial function in humans, we compared the ability of the endothelium-dependent vasodilator acetylcholine to increase conduit coronary diameter (the macrovascular response) and coronary blood flow velocity (the microvascular response) in 12 cardiac transplant recipients without diabetes before and after blood glucose was raised from 6.7 +/- 1.3 mmol/l (121 +/- 24 mg/dl) to 17.8 +/- 1.5 mmol/l (321 +/- 27 mg/dl) for 1 h. Hyperglycemia acutely doubled circulating levels of the oxidation product malondialdehyde, indicating systemic oxidative stress, but did not affect the ability of acetylcholine to dilate conduit coronary segments or accelerate coronary blood flow. We conclude that the oxidative stress associated with a single acute episode of hyperglycemia affects neither acetylcholine-mediated coronary endothelial NO release nor the subsequent bioavailability, metabolism, or action of NO within the coronary circulation of cardiac transplant recipients. These observations imply that the relationship among hyperglycemia, oxidative stress, and coronary endothelial dysfunction is presumably mediated by mechanisms operating over longer periods of time.


Assuntos
Velocidade do Fluxo Sanguíneo , Circulação Coronária , Vasos Coronários/fisiopatologia , Endotélio Vascular/fisiopatologia , Transplante de Coração , Hipoglicemia/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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