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1.
Circulation ; 104(25): 3020-2, 2001 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-11748092

RESUMO

BACKGROUND: We used serial volumetric (post-irradiation and follow-up) intravascular ultrasound (IVUS) to compare the effectiveness of gamma-irradiation ((192)Ir) in saphenous vein graft (SVG) versus native coronary artery in-stent restenosis (ISR). METHODS AND RESULTS: The study population consisted of 47 patients with native coronary artery ISR from WRIST (Washington Radiation for In-Stent Restenosis Trial) and 31 patients with SVG ISR (12 from the WRIST and 19 from SVGWRIST). After irradiation and at 6-month follow-up, stent, lumen, and intimal hyperplasia (IH, stent minus lumen) areas were measured every 1 mm. ISR length was similar in the 2 groups (29+/-12 versus 29+/-14 mm, P=0.9). Post-intervention measurements of stent (280+/-154 versus 324+/-270 mm(3), P=0.4), lumen (184+/-91 versus 214+/-172 mm(3), P=0.3), and IH (96+/-77 versus 109+/-119 mm(3), P=0.5) volumes were similar in the 2 groups. The post-intervention minimum lumen cross sectional areas tended to be smaller in native artery ISR lesions (4.7+/-1.7 versus 5.4+/-1.6 mm(2), P=0.11). During follow-up, there was a slight increase in IH volume (9+/-38 mm(3)) in native artery ISR lesions and a slight decrease in IH volume in SVG ISR lesions (-9+/-32 mm(3), P=0.0463). There was also a slight decrease in minimum lumen area in the native artery ISR lesions versus a slight increase in minimum lumen area in the SVG ISR lesions (-0.8+/-1.7 versus 0.2+/-1.1, P=0.0087). As a result, the follow-up minimum lumen area in native artery lesions was smaller than in SVG ISR lesions (4.1+/-2.1 mm(2) versus 5.6+/-2.2 mm(2), P=0.0067). CONCLUSION: gamma-Irradiation with (192)Ir brachytherapy appears to be as effective in SVGs as it is in native artery ISR lesions.


Assuntos
Doença das Coronárias/radioterapia , Vasos Coronários/efeitos da radiação , Raios gama/uso terapêutico , Veia Safena/transplante , Stents , Idoso , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/terapia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Resultado do Tratamento , Ultrassonografia de Intervenção
2.
JAMA ; 286(16): 2011-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11667938

RESUMO

CONTEXT: Use of anorexigen therapy is associated with valvular abnormalities, although there is limited information on long-term changes in valvular regurgitation following discontinuation of these agents. OBJECTIVE: To evaluate changes in valvular regurgitation, valve morphology, and clinical parameters 1 year after an initial echocardiogram in patients previously treated with dexfenfluramine or phentermine/fenfluramine and in untreated controls. DESIGN AND SETTING: A reader-blinded, multicenter, echocardiographic and clinical 1-year follow-up study at 25 outpatient clinical sites. PATIENTS: A total of 1142 obese patients (1466 participated in the initial study) who had follow-up echocardiogram; all but 4 had a follow-up medical history and physical examination. Follow-up time from discontinuation of drug to follow-up echocardiogram for 371 dexfenfluramine patients was 17.5 months (range, 13-26 months) and for 340 phentermine/fenfluramine patients was 18.7 months (range, 13-26 months) after discontinuation of drug therapy. MAIN OUTCOME MEASURE: Change in grade of valvular regurgitation and valve morphology and mobility. RESULTS: Echocardiographic changes in aortic regurgitation were observed in 8 controls (7 [1.7%] had decreases; 1 [0.2%] had an increase); 29 dexfenfluramine patients (23 [6.4%] had decreases; 6 [1.7%] had increases; P<.001 vs controls); and 15 phentermine/fenfluramine patients (4.5% all decreases; P =.03 vs controls). No statistically significant differences were observed when treated patients were compared with controls for changes in medical history, physical findings, mitral regurgitation, aortic or mitral leaflet mobility or thickness, pulmonary artery systolic pressure, ejection fraction, valve surgery, or cardiovascular events. CONCLUSION: Progression of valvular abnormalities is unlikely in patients 1 year after an initial echocardiogram and 13 to 26 months after discontinuation of dexfenfluramine and phentermine/fenfluramine.


Assuntos
Depressores do Apetite/efeitos adversos , Estimulantes do Sistema Nervoso Central/efeitos adversos , Dexfenfluramina/efeitos adversos , Fenfluramina/efeitos adversos , Doenças das Valvas Cardíacas/induzido quimicamente , Doenças das Valvas Cardíacas/diagnóstico por imagem , Fentermina/efeitos adversos , Serotoninérgicos/efeitos adversos , Adulto , Idoso , Insuficiência da Valva Aórtica/induzido quimicamente , Insuficiência da Valva Aórtica/diagnóstico por imagem , Ecocardiografia , Feminino , Seguimentos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/induzido quimicamente , Insuficiência da Valva Mitral/diagnóstico por imagem , Obesidade/tratamento farmacológico
3.
Leuk Lymphoma ; 42(1-2): 99-108, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11699227

RESUMO

In an ongoing study, families with two or more living cases of B-CLL in first-degree relatives have been recruited through physician and self-referral. Since 1967, 28 kindreds with 73 cases of B-CLL have been enrolled within the National Cancer Institute (NCI) Familial B-CLL Registry. Medical, clinical, and demographic information have been obtained from private physicians, patient interview, hospital records, and death certificates. We used SEER Registry data to compare characteristics of sporadic B-CLL to familial B-CLL. The mean age at diagnosis was approximately 10 years younger among familial cases (57.9 +/- 12.1) than that observed in sporadic cases (70.1 +/- 11.9). A higher percentage of second primary tumors among familial CLL cases compared to reports in sporadic was also observed (16% vs. 8.8%). However, the transformation rate to non-Hodgkin's lymphoma does not appear to be different from that reported for sporadic cases. In conclusion, we observed some differences between familial and sporadic cases; whether any of these characteristics affect survival time or severity of disease is unknown. The study of families with multiple B-CLL cases will aid in delineating the genes and environmental factors that may play a role in the development of both forms of B-CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B/genética , Sistema de Registros/estatística & dados numéricos , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Transformação Celular Neoplásica , Saúde da Família , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/epidemiologia , Estudos Longitudinais , Linfoma não Hodgkin , Masculino , Pessoa de Meia-Idade , National Institutes of Health (U.S.) , Segunda Neoplasia Primária , Linhagem , Remissão Espontânea , Estados Unidos
5.
Circulation ; 104(8): 856-9, 2001 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-11514368

RESUMO

BACKGROUND: The efficacy of coronary gamma-irradiation in preventing recurrent in-stent restenosis (ISR) is well established. However, brachytherapy may be less effective in very long, diffuse ISR lesions. METHODS AND RESULTS: We used serial intravascular ultrasound (IVUS) to study patients with long, diffuse ISR lesions (length, 36 to 80 mm) who were enrolled in (1) Long WRIST (Washington Radiation In-Stent Restenosis Trial), a double-blind, placebo-controlled trial of intracoronary gamma-irradiation (15 Gy at 2 mm from the source) and (2) high-dose (HD) Long WRIST, a registry that used a dose prescription of 18 Gy at 2 mm from the source. IVUS was performed using automated pullback (0.5 mm/s). Stent, lumen, and intimal hyperplasia were measured at 2-mm intervals. Complete postintervention and follow-up IVUS imaging was available in 30 irradiated and 34 placebo patients from Long WRIST and in 25 patients from HD Long WRIST. Stent length was longer in HD Long WRIST than in placebo or treated patients in Long WRIST (P=0.0064 and P=0.0125, respectively). Otherwise, baseline measurements were similar. At follow-up, the minimum lumen area was largest in the HD Long WRIST patients (4.0+/-1.4 mm(2)); areas were 2.9+/-1.0 mm(2) in irradiated patients in Long WRIST and 1.9+/-1.1 mm(2) in placebo patients in Long WRIST (P<0.005 for all comparisons). CONCLUSIONS: - Serial IVUS analysis shows that gamma-irradiation reduces recurrent in-stent neointimal hyperplasia in long, diffuse ISR lesions; however, it is even more effective when given at a higher dose.


Assuntos
Raios gama/uso terapêutico , Oclusão de Enxerto Vascular/prevenção & controle , Revascularização Miocárdica , Stents , Ultrassonografia de Intervenção , Braquiterapia/métodos , Doença das Coronárias/cirurgia , Relação Dose-Resposta à Radiação , Método Duplo-Cego , Oclusão de Enxerto Vascular/classificação , Oclusão de Enxerto Vascular/diagnóstico , Humanos , Pessoa de Meia-Idade , Revascularização Miocárdica/efeitos adversos , Revascularização Miocárdica/métodos , Fatores de Risco , Prevenção Secundária , Stents/efeitos adversos , Resultado do Tratamento , Grau de Desobstrução Vascular/efeitos da radiação
6.
Am J Cardiol ; 88(3): 248-52, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11472702

RESUMO

Intimal hyperplasia within the body of the stent is the primary mechanism for in-stent restenosis; however, stent edge restenosis has been described after brachytherapy. Our current understanding about the magnitude of in vivo intimal hyperplasia and edge restenosis is limited to data obtained primarily from select, symptomatic patients requiring repeat angiography. The purpose of this study was to determine the extent and distribution of intimal hyperplasia both within the stent and along the stent edge in relatively nonselect, asymptomatic patients scheduled for 6-month intravascular ultrasound (IVUS) as part of a multicenter trial: Heparin Infusion Prior to Stenting. Planar IVUS measurements 1 mm apart were obtained throughout the stent and over a length of 10 mm proximal and distal to the stent at index and follow-up. Of the 179 patients enrolled, 140 returned for repeat angiography and IVUS at 6.4 +/- 1.9 months and had IVUS images adequate for analysis. Patients had 1.2 +/- 0.6 Palmaz-Schatz stents per vessel. There was a wide individual variation of intimal hyperplasia distribution within the stent and no mean predilection for any location. At 6 months, intimal hyperplasia occupied 29.3 +/- 16.2% of the stent volume on average. Lumen loss within 2 mm of the stent edge was due primarily to intimal proliferation. Beyond 2 mm, negative remodeling contributed more to lumen loss. Gender, age, vessel location, index plaque burden, hypercholesterolemia, diabetes, and tobacco did not predict luminal narrowing at the stent edges, but diabetes, unstable angina at presentation, and lesion length were predictive of in-stent intimal hyperplasia. In a non-radiation stent population, 29% of the stent volume is filled with intimal hyperplasia at 6 months. Lumen loss at the stent edge is due primarily to intimal proliferation.


Assuntos
Doença das Coronárias/patologia , Stents , Túnica Íntima/patologia , Doença das Coronárias/terapia , Feminino , Seguimentos , Humanos , Hiperplasia/etiologia , Hiperplasia/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Estudos Prospectivos , Recidiva , Stents/efeitos adversos
7.
Am J Cardiol ; 87(10): 1145-9, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11356387

RESUMO

In the Washington Radiation for In-Stent restenosis Trial (WRIST), patients were first treated with conventional techniques and then randomized to either gamma-irradiation ((192)Ir) or placebo (dummy seeds). In the (192)Ir group with native coronary in-stent restenosis, we identified 8 patients with edge recurrence and compared them with 21 patients with no recurrence. Serial (postirradiation and follow-up) intravascular ultrasound analysis was performed according to conventional methods. When compared with nonrecurring lesions, lesions with distal edge recurrence had (1) greater decrease in mean distal lumen cross-sectional area (-3.0 +/- 1.2 vs -0.7 +/- 1.0 mm(2), p = 0.0002), (2) no change in mean distal external elastic membrane cross-sectional area versus an increase in mean distal cross-sectional area of 1.0 +/- 0.9 mm(2) in nonrecurring lesions (p = 0.0047), and (3) a greater increase in mean distal plaque + media cross-sectional area (2.9 +/- 1.2 mm vs 1.7 +/- 0.6 mm(2), p = 0.0103). Within the stented segment, the nonrecurring lesions had no decrease in mean lumen and no increase in mean intimal hyperplasia cross-sectional area. Conversely, lesions with distal edge recurrence had a significant decrease in mean intrastent lumen cross-sectional area (-1.7 +/- 1.7 mm(2)) and a significant increase in mean intrastent intimal hyperplasia cross-sectional area (1.6 +/- 1.6 mm(2)). Lesions with distal edge recurrence also had a greater decrease in mean proximal lumen cross-sectional area (-1.7 +/- 1.3 vs -0.3 +/- 0.8 mm(2), p = 0.0213), with a trend toward a greater increase in mean proximal plaque + media cross-sectional area. Thus, edge recurrence after (192)Ir treatment of in-stent restenosis is the result of neointimal hyperplasia (part of generalized treatment failure) and the absence of radiation-induced positive remodeling.


Assuntos
Braquiterapia , Doença das Coronárias/terapia , Vasos Coronários/diagnóstico por imagem , Stents , Ultrassonografia de Intervenção , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/radioterapia , Vasos Coronários/efeitos da radiação , Humanos , Radioisótopos de Irídio/uso terapêutico , Recidiva
8.
J Am Coll Cardiol ; 37(6): 1726-32, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11345391

RESUMO

OBJECTIVES: We tested the hypothesis that intramyocardial injection of autologous bone marrow (ABM) promotes collateral development in ischemic porcine myocardium. We also defined, in vitro, whether bone marrow (BM) cells secrete vascular endothelial growth factor (VEGF) and macrophage chemoattractant protein-1 (MCP-1). BACKGROUND: The natural processes leading to collateral development are extremely complex, requiring multiple growth factors interacting in concert and in sequence. Because optimal angiogenesis may, therefore, require multiple angiogenic factors, we thought that injection of BM, which contains cells that secrete numerous angiogenic factors, might provide optimal therapeutic angiogenesis. METHODS: Bone marrow was cultured four weeks in vitro. Conditioned medium was assayed for VEGF and MCP-1 and was added to cultured pig aortic endothelial cells (PAEC) to assess proliferation. Four weeks after left circumflex ameroid implantation, freshly aspirated ABM (n = 7) or heparinized saline (n = 7) was injected transendocardially into the ischemic zone (0.2 ml/injection at 12 sites). Echocardiography to assess myocardial thickening and microspheres to assess perfusion were performed at rest and during stress. RESULTS: Vascular endothelial growth factor and MCP-1 concentrations increased in a time-related manner. The conditioned medium enhanced, in a dose-related manner, PAEC proliferation. Collateral flow (ischemic/normal zone X 100) improved in ABM-treated pigs (ABM: 98 +/- 14 vs. 83 +/- 12 at rest, p = 0.001; 89 +/- 18 vs. 78 +/- 12 during adenosine, p = 0.025; controls: 92 +/- 10 vs. 89 +/- 9 at rest, p = 0.49; 78 +/- 11 vs. 77 +/- 5 during adenosine, p = 0.75). Similarly, contractility increased in ABM-treated pigs (ABM: 83 +/- 21 vs. 60 +/- 32 at rest, p = 0.04; 91 +/- 44 vs. 36 +/- 43 during pacing, p = 0.056; controls: 69 +/- 48 vs. 64 +/- 46 at rest, p = 0.74; 65 +/- 56 vs. 37 +/- 56 during pacing, p = 0.23). CONCLUSIONS: Bone marrow cells secrete angiogenic factors that induce endothelial cell proliferation and, when injected transendocardially, augment collateral perfusion and myocardial function in ischemic myocardium.


Assuntos
Transplante de Medula Óssea/métodos , Circulação Colateral/fisiologia , Modelos Animais de Doenças , Endocárdio , Contração Miocárdica/fisiologia , Isquemia Miocárdica/terapia , Neovascularização Fisiológica/fisiologia , Animais , Transplante de Medula Óssea/instrumentação , Células Cultivadas , Quimiocina CCL2 , Doença Crônica , Ecocardiografia , Fatores de Crescimento Endotelial , Teste de Esforço , Estudos de Viabilidade , Injeções/instrumentação , Injeções/métodos , Linfocinas , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/patologia , Isquemia Miocárdica/fisiopatologia , Fragmentos de Peptídeos , Distribuição Aleatória , Suínos , Transplante Autólogo/métodos , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
9.
Circulation ; 103(2): 188-91, 2001 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-11208674

RESUMO

BACKGROUND: The relation between lesion length and effectiveness of brachytherapy is not well studied. METHODS AND RESULTS: We compared serial (postintervention and follow-up) intravascular ultrasound findings in 66 patients with native coronary artery in-stent restenosis (ISR) who were treated with (192)Ir (15 Gy delivered 2 mm away from the radiation source). Patients were enrolled in the Washington Radiation for In-Stent Restenosis Trial (WRIST; ISR length, 10 to 47 mm; n=36) or Long WRIST (ISR length, 36 to 80 mm; n=30). External elastic membrane, stent, lumen, and intimal hyperplasia (IH; stent minus lumen) areas and source-to-target (intravascular ultrasound catheter to external elastic membrane) distances were measured. Postintervention stent areas were larger in WRIST and smaller in Long WRIST patients (P:<0.0001). At follow-up, maximum IH area significantly increased in both WRIST and Long WRIST patients (P:<0.0001 for both), but this increase was greater in Long WRIST patients (P:=0.0006). Similarly, minimum lumen cross-sectional area significantly decreased in both WRIST and Long WRIST patients (P:<0.05 and P:<0.0001, respectively), but this decrease was more pronounced in Long WRIST patients (P:=0.0567). The maximum source-to-target distance was longer in Long WRIST than in WRIST, and it correlated directly with ISR length (r=0.547, P:<0.0001). Overall, the change in minimum lumen area and the change in maximum IH area correlated with the maximum source-to-target distance (r=0.352, P:=0.0038 and r=0.523, P:<0.0001 for WRIST and Long WRIST, respectively). The variability (maximum/minimum) in IH area at follow-up also correlated with the maximum source-to-target distance (r=0.378, P:<0.0001). CONCLUSIONS: Brachytherapy may be less effective in longer ISR lesions because of the greater variability and longer source-to-target distances in diffuse ISR.


Assuntos
Braquiterapia , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/radioterapia , Raios gama/uso terapêutico , Stents , Ultrassonografia de Intervenção , Braquiterapia/normas , Reestenose Coronária/prevenção & controle , Estenose Coronária/prevenção & controle , Vasos Coronários/diagnóstico por imagem , Seguimentos , Humanos , Hiperplasia , Radioisótopos de Irídio/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Túnica Íntima/diagnóstico por imagem , Ultrassonografia de Intervenção/métodos
11.
Am J Cardiol ; 85(1): 37-40, 2000 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11078233

RESUMO

Current methods of calcium quantification by intravascular ultrasound (IVUS) measure the arc of calcium using the cross-sectional image at the lesion and at the reference site while neglecting calcium elsewhere. Calcium at these sites may not adequately represent the extent of total epicardial coronary calcium. We devised a new method to quantify calcium as a percentage of the coronary luminal surface. This study examines whether this new method accurately reflects coronary calcium determined by histology. Seventeen postmortem coronary arteries were pressure-fixed and imaged by IVUS using a motorized pullback device. Total plaque-luminal circumferential length and calcified plaque-luminal circumferential length were measured from serial cross-sectional IVUS images every 1 mm. With use of Simpson's method, the total plaque and calcified plaque surface area was then calculated. Histologic sections were stained with hematoxylin-eosin and Movat pentachrome at 3-mm intervals. Calcium was independently quantified by planimetry under light microscopy. Histologic analysis (n = 253 sections) revealed a wide range of calcium (0 to 47 mm2; mean 12 +/- 16 mm3). The IVUS-derived calcified plaque surface area was 17 +/- 23 mm2), which represented 3.1 +/- 4.1% (range 0% to 13.9%) of the total plaque surface area. The histologic and IVUS quantification of calcium by this method was strongly related (r = 0.84, p <0.0001), which was an improvement over current 2-dimensional measures of calcium arc (r = 0.41, p = 0.18). Calculation of calcified plaque surface area from sequential IVUS images appears to accurately reflect the degree of total coronary calcification.


Assuntos
Calcinose/diagnóstico por imagem , Calcinose/patologia , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/patologia , Ultrassonografia de Intervenção/métodos , Idoso , Aterectomia Coronária , Autopsia , Calcinose/complicações , Calcinose/terapia , Distribuição de Qui-Quadrado , Contraindicações , Doença das Coronárias/complicações , Doença das Coronárias/terapia , Morte Súbita Cardíaca/etiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Índice de Gravidade de Doença
12.
Am J Cardiol ; 85(5): 651-3, A10, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11078283

RESUMO

We compared postintervention and follow-up intravascular ultrasound findings of 25 patients from the beta-Washington Radiation for InStent restenosis Trial (in which all patients received radiation) and 75 patients from the Washington Radiation for InStent restenosis Trial (in which patients were randomized to gamma irradiation). The decrease in lumen volume was similar for beta versus gamma and less in both gamma versus placebo and beta versus placebo; the increase in intimal hyperplasia volume was similar for beta versus gamma and greater in both beta versus placebo and gamma versus placebo.


Assuntos
Partículas beta/uso terapêutico , Braquiterapia , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/radioterapia , Stents , Ultrassonografia de Intervenção , Doença das Coronárias/prevenção & controle , Seguimentos , Humanos , Radioisótopos de Irídio/uso terapêutico , Recidiva , Fatores de Tempo , Radioisótopos de Ítrio/uso terapêutico
14.
Circulation ; 102(1): 7-10, 2000 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-10880407

RESUMO

BACKGROUND: Intravascular ultrasound analysis has assessed mechanisms of lumen enlargement after nonstent interventions, but not after stenting. METHODS AND RESULTS: Preintervention and postintervention intravascular ultrasound was used to study 25 de novo native coronary lesions treated with single MultiLink stents without preatheroablation. External elastic membrane, lumen, and plaque and media (P&M) areas were measured every 1 mm to include the lesion and reference segments that were 5 mm proximal and distal to it. Lesion mean lumen area increased from 4.0+/-1.0 mm(2) before the intervention to 8.8+/-2.0 mm(2) after the intervention (P<0.0001) as a result of an increase in mean external elastic membrane area (14. 2+/-2.7 to 16.1+/-3.0 mm(2), P<0.0001) and a decrease in mean P&M area (10.2+/-2.2 to 7.2+/-1.8 mm(2), P<0.0001). The decrease in lesion P&M was accompanied by an increase in both proximal reference mean P&M (7.0+/-1.9 to 8.4+/-2.0 mm(2), P<0.0001) and distal reference mean P&M (5.8+/-2.1 to 7.2+/-2.1 mm(2), P<0.0001). Volumetric analysis showed an axial redistribution of plaque away from the center of the lesion toward the reference segments to increase the plaque burden in both the proximal and distal reference segments. Total (lesion plus reference) mean P&M decreased from 8. 6+/-2.1 to 7.5+/-1.8 mm(2) (P<0.0001). CONCLUSIONS: The mechanisms of lumen enlargement after stenting involved (1) significant axial redistribution of plaque from the lesion into the reference segments, (2) vessel expansion, and (3) either plaque embolization or compression.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/terapia , Revascularização Miocárdica/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Stents , Idoso , Estudos de Coortes , Angiografia Coronária , Circulação Coronária , Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Revascularização Miocárdica/instrumentação , Ultrassonografia
15.
Circulation ; 101(19): 2227-30, 2000 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-10811587

RESUMO

BACKGROUND: The effects of endovascular irradiation on uninjured reference segments during the treatment of in-stent restenosis are unknown. METHODS AND RESULTS: In the Washington Radiation for In-Stent restenosis Trial (WRIST), patients with in-stent restenosis were first treated with conventional catheter-based techniques and then randomized (blinded) to receive either gamma-irradiation ((192)Ir) or a placebo (dummy seeds). We identified all patients in whom the active (n=19) or dummy seeds (n=19) extended >10 mm proximal and distal to the in-stent restenosis lesion. Serial (postirradiation and follow-up) external elastic membrane (EEM), lumen, and plaque and media (EEM-lumen) areas were measured (using intravascular ultrasound) every 1 mm over 5-mm-long reference segments that were 6 to 10 mm proximal and distal to the in-stent restenosis lesion. During follow-up, a similar small increase occurred in the plaque and media area in the proximal and distal reference segments in both (192)Ir and placebo patients. However, in the (192)Ir patients, an increase in both proximal and distal EEM area occurred; as a result, no change in lumen area occurred. Conversely, in the placebo patients, the proximal reference EEM area decreased, and no change occurred in the distal reference EEM area; this contributed to a decrease in lumen area. CONCLUSIONS: There was no evidence of a deleterious effect of gamma-irradiation on angiographically normal uninjured reference segments in the first 6 months after the treatment of in-stent restenosis.


Assuntos
Doença das Coronárias/radioterapia , Vasos Coronários/efeitos da radiação , Stents , Doença das Coronárias/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Método Duplo-Cego , Tecido Elástico/diagnóstico por imagem , Tecido Elástico/efeitos da radiação , Humanos , Recidiva , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia de Intervenção
16.
Circulation ; 102(24): 2915-8, 2000 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-11113039

RESUMO

BACKGROUND: The aim of this study was to use serial volumetric intravascular ultrasound to evaluate the effect of gamma-radiation on recurrent in-stent restenosis. METHODS AND RESULTS: After successful reintervention, patients were randomized to receive either (192)Ir or placebo. Intravascular ultrasound studies with motorized pullback (0.5 mm/s) were performed immediately after irradiation and at 8-month follow-up in 70 patients. Paired volumetric analysis of the stented segment and of 5-mm proximal and distal reference segments was performed; this included measurements of the external elastic membrane, lumen, plaque and media (external elastic membrane minus lumen), stent, and intimal hyperplasia (stent minus lumen). Baseline proximal reference, stent, and distal reference measurements were similar in both groups. The changes in proximal and distal reference measurements of the external elastic membrane, plaque and media, and lumen areas were similar in both groups. However, the decrease in stented segment lumen volume was less in the (192)Ir patients than the placebo patients (-25+/-34 mm(3) versus -48+/-42 mm(3); P:=0.0225), and the increase in the volume of intimal hyperplasia in the stented segment was less in the (192)Ir patients than in the placebo patients (28+/-37 mm(3) versus 50+/-40 mm(3); P:=0.0352). When averaged over the length of the stented segment (32+/-13 mm versus 33+/-14 mm; P:=0.9), the increase in mean area of intimal hyperplasia was 0.8+/-1.0 mm(2) in the (192)Ir group and 1.6+/-1.2 mm(2) in the control group (P:=0.0065). Late stent-vessel wall malapposition was noted in one placebo patient and no (192)Ir patients. CONCLUSIONS: gamma-Radiation therapy can effectively prevent recurrent in-stent restenosis by inhibiting neointimal formation within the stent. At the stent edge, there were no significant differences between (192)Ir and placebo patients.


Assuntos
Doença das Coronárias/terapia , Raios gama , Falha de Prótese , Stents , Análise de Variância , Doença das Coronárias/etiologia , Vasos Coronários/patologia , Vasos Coronários/efeitos da radiação , Seguimentos , Humanos , Hiperplasia/prevenção & controle , Irídio
17.
Am J Cardiol ; 84(1): 37-40, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10404848

RESUMO

We sought to determine the patient and plaque characteristics associated with the different forms of arterial remodeling as seen by intravascular ultrasound (IVUS) before coronary intervention. Remodeling in response to plaque accumulation may occur in the form of compensatory enlargement and/or focal vessel contraction. Previous studies report variation in the frequency and form of arterial remodeling. We performed preintervention IVUS imaging on 169 patients. Vessels were categorized as exhibiting compensatory enlargement or focal contraction if the arterial area at the lesion was larger or smaller, respectively, than both proximal and distal reference arterial areas; otherwise the artery was considered not to have undergone significant remodeling. Calcification was assessed and noncalcified plaque density was measured by videodensitometry. Sixty-one of 169 patients (66 narrowings) (46 men and 15 women, age 56+/-11 years) had adequate reference segments. Remodeling occurred in 43 of 66 patients (65%): compensatory enlargement in 27 of 66 (41%) and focal contraction in 16 of 66 (24%). Lesions with focal contraction had significantly smaller arterial area (13.3+/-3.3 vs. 18.1+/-7.0 mm2, p = 0.02) and plaque area (9.5+/-2.8 vs 13.7+/-5.5 mm2, p<0.01). Cross-sectional stenosis was similar (71+/-9% vs. 75+/-10%, p = NS), as was plaque density (p = 0.20), eccentricity, and calcium. Patient age, gender, and lesion location were not related to the form of remodeling. Similarly, history of diabetes, hypercholesterolemia, or hypertension was not predictive. Smoking was the only risk factor associated with focal contraction (p<0.01). Thus, whereas compensatory enlargement appears to be the most common form of coronary artery remodeling, focal contraction occurs more often in smokers.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Ultrassonografia de Intervenção , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/epidemiologia
18.
Qual Manag Health Care ; 7(2): 11-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10346458

RESUMO

To determine the best source of high-quality data related to mammography rates, a study was undertaken to compare chart audit and claims data from the Health Care Financing Administration's Ambulatory Quality Improvement Project. Because claims data captured a higher percentage of mammograms than chart audit data in this study, quality improvement projects should consider utilizing claims data only to ascertain mammography rates.


Assuntos
Revisão da Utilização de Seguros/estatística & dados numéricos , Mamografia/estatística & dados numéricos , Gestão da Qualidade Total/métodos , Revisão da Utilização de Recursos de Saúde/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/complicações , Neoplasias da Mama/diagnóstico , Centers for Medicare and Medicaid Services, U.S. , Coleta de Dados , Complicações do Diabetes , Feminino , Pesquisas sobre Atenção à Saúde/métodos , Humanos , Medicare , Estados Unidos
19.
Am J Public Health ; 89(1): 61-5, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9987466

RESUMO

OBJECTIVES: Expert panels determined the public health goals of Healthy People 2000 subjectively. The present study examined whether data-driven benchmarks provide a better alternative. METHODS: We developed the "pared-mean" method to define from data the best achievable health care practices. We calculated the pared-mean benchmark for screening mammography from the 1994 National Health Interview Survey, using the metropolitan statistical area as the "provider" unit. Beginning with the best-performing provider and adding providers in descending sequence, we established the minimum provider subset that included at least 10% of all women surveyed on this question. The pared-mean benchmark is then the proportion of women in this subset who received mammography. RESULTS: The pared-mean benchmark for screening mammography was 71%, compared with the Healthy People 2000 goal of 60%. CONCLUSIONS: For Healthy People 2010, benchmarks derived from data reflecting the best available care provide viable alternatives to consensus-derived targets. We are currently pursuing additional refinements to the data-driven pared-mean benchmark approach.


Assuntos
Benchmarking/organização & administração , Interpretação Estatística de Dados , Medicina Baseada em Evidências , Diretrizes para o Planejamento em Saúde , Prioridades em Saúde/organização & administração , Feminino , Previsões , Humanos , Mamografia/normas , Programas de Rastreamento/normas , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estados Unidos
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