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1.
Science ; 181(4105): 1172-5, 1973 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-4353653

RESUMO

Angiotensin II applied directly to the subfornical organ in a dose as small as 0.1 nanogram elicited short-latency drinking behavior in water-sated rats. Lesions in the body of this structure blocked drinking induced by angiotensin II applied to the basal telencephalon (including preoptic area). These results call attention to the subfornical organ as an important central nervous structure involved in the conrol of drinking behavior.


Assuntos
Angiotensina II/farmacologia , Ventrículos Cerebrais/fisiologia , Comportamento de Ingestão de Líquido , Angiotensina II/administração & dosagem , Animais , Ventrículos Cerebrais/efeitos dos fármacos , Denervação , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Injeções , Masculino , Ratos , Técnicas Estereotáxicas , Telencéfalo
2.
Health Phys ; 91(6): 570-3, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17099400

RESUMO

The radiation safety implications following the administration of 131I for the treatment of Grave's disease to a patient undergoing home-based renal dialysis was investigated. External dose-rate measurements from the patient revealed a peak value at around day 2, post administration. The effective half-life was determined as 6.5 d. From day 3, the clearance of 131I was observed to be fairly constant and equated to 2.7% per day or 5.4% per dialysis session. From this the biological half-life was determined as 15 d. Radiation monitoring of the dialysis unit, disposables, and bed linen found no detectable contamination. For the purpose of useful protection, at a distance of 1 m from the patient, the average dose rate over the effective treatment duration was determined to be 8 microSv h(-1) and at 2 m distance, 2.6 microSv h(-1). Thus, in order to keep below a level of dose constraint of 3 mSv the total allowable time spent at 1 m would be 375 h or 15 h per day. To comply with a 1-mSv constraint, the average daily exposure allowable at 1 m would be 5 h per day. Neither of these time limits would be difficult to achieve for the majority of situations with fairly modest behavioral constraints. Initial discharge concentration rates into the waste water system are estimated at 200 MBq m(-3) and therefore might need to be considered depending upon the regulatory environment.


Assuntos
Doença de Graves/radioterapia , Hemodiálise no Domicílio , Falência Renal Crônica/terapia , Proteção Radiológica , Feminino , Doença de Graves/complicações , Humanos , Radioisótopos do Iodo , Falência Renal Crônica/complicações , Doses de Radiação
3.
Cancer Res ; 45(2): 601-7, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3967235

RESUMO

Trifluralin, a widely used herbicide, added to the diet before the p.o. administration of benzo(a)pyrene (BP) and fed continuously, significantly inhibited the induction of lung and forestomach tumors in female A/J mice. Dietary intake of trifluralin before the administration of BP resulted in a significant increase in glutathione in lung and forestomach but not in liver and glandular stomach. Trifluralin treatment also inhibited the binding of [3H]BP to liver and lung DNA, as well as to protein in the liver. Under these conditions, the protection against BP-induced lung tumors and perhaps forestomach tumors may be due to an elevation of tissue glutathione, resulting in a decreased binding of reactive metabolites of BP to macromolecules at these sites. The results indicate that trifluralin has a "blocking" effect in its inhibition of BP-induced tumors. Our studies show that trifluralin also inhibits chemical carcinogenesis in lung and forestomach when started in the diet 1 day after the administration of BP and fed continuously thereafter. In the case of lung, although maximum inhibition of tumors occurred when trifluralin was started 1 day after BP, there was significant protection at all time intervals (0 to 7 days) against lung tumors. The finding that trifluralin protects against BP tumorigenesis when started in the diet after the administration of the carcinogen clearly demonstrates that trifluralin also has a "suppressive" effect against BP-induced tumors.


Assuntos
Benzo(a)pireno , Neoplasias Pulmonares/prevenção & controle , Neoplasias Gástricas/prevenção & controle , Toluidinas/uso terapêutico , Trifluralina/uso terapêutico , Animais , Benzopireno Hidroxilase/metabolismo , Peso Corporal/efeitos dos fármacos , DNA/metabolismo , Dieta , Feminino , Glutationa/metabolismo , Neoplasias Pulmonares/induzido quimicamente , Camundongos , Camundongos Endogâmicos A , Tamanho do Órgão/efeitos dos fármacos , Neoplasias Gástricas/induzido quimicamente , Fatores de Tempo
4.
J Am Coll Cardiol ; 11(5): 977-82, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-2965718

RESUMO

The reperfusion catheter is a 4.3F catheter with 30 holes over its distal 10 cm. It is used to maintain coronary blood flow in patients awaiting emergency coronary bypass surgery after failed coronary angioplasty. The insertion of the reperfusion catheter was attempted in 20 patients (14 with total occlusion and 6 with severe residual stenosis judged to be in jeopardy of reclosure before operation). The reperfusion catheter was successfully placed across the obstruction in 18 patients (90%). After successful insertion of the reperfusion catheter, 16 patients had good anterograde flow (Thrombolysis in Myocardial Infaction [TIMI] trial grade II or III); angiographic improvement was associated with significant lessening of ST segment elevation as well as a decrease in chest pain in most patients. Two patients had poor or absent anterograde flow (TIMI grade O or I) because of extensive preexisting intracoronary thrombosis; one died from refractory ventricular fibrillation. In each of the remaining patients emergency coronary bypass surgery was performed with no deaths or significant cardiac complications. The reperfusion catheter is a safe and effective method to reestablish and maintain coronary blood flow before coronary bypass surgery after failed coronary angioplasty. Because there is the potential risk of serious complications, particularly thrombus formation within this catheter, the reperfusion catheter should be used cautiously and the patient should undergo immediate bypass surgery.


Assuntos
Angioplastia com Balão , Cateterismo Cardíaco/instrumentação , Ponte de Artéria Coronária , Circulação Coronária , Doença das Coronárias/terapia , Angioplastia com Balão/efeitos adversos , Cateterismo Cardíaco/métodos , Cateteres de Demora , Angiografia Coronária , Doença das Coronárias/cirurgia , Emergências , Estudos de Avaliação como Assunto , Seguimentos , Humanos , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/prevenção & controle , Recidiva , Estudos Retrospectivos
5.
J Am Coll Cardiol ; 15(2): 419-25, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2137149

RESUMO

Atherectomy is a new therapeutic intervention for the treatment of peripheral arterial disease, and permits the controlled excision and retrieval of portions of stenosing lesions. The gross and light microscopic features of 218 peripheral arterial stenoses resected from 100 patients by atherectomy were studied. One hundred seventy of these lesions were primary stenoses and 48 were restenoses subsequent to prior angioplasty or atherectomy. Microscopically, primary stenoses were composed of atherosclerotic plaque (150 lesions), fibrous intimal thickening (15 lesions) or thrombus alone (5 lesions). Atherosclerotic plaques had a variable morphology and, in one-third of cases, were accompanied by abundant surface thrombus that probably added to the severity of stenosis. Most patients with fibrous intimal thickening or thrombus alone had typical atherosclerotic plaque removed elsewhere from within the same artery. Intimal hyperplasia, with or without underlying residual plaque, was found at 36 sites of restenosis, the remaining 12 consisting of plaque only. Intimal hyperplasia had a distinctive histologic appearance and was due to smooth muscle cell proliferation within a loosely fibrous stroma. Superimposed thrombus may have contributed to arterial narrowing in 25% of hyperplastic and 8% of atherosclerotic restenoses (p = 0.41). Pathologic examination of tissues recovered by peripheral atherectomy is an important adjunct that may provide insight into the efficacy of vascular interventions and the phenomenon of postintervention restenosis.


Assuntos
Arteriopatias Oclusivas/cirurgia , Artérias/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão , Arteriopatias Oclusivas/patologia , Arteriopatias Oclusivas/terapia , Arteriosclerose/patologia , Constrição Patológica , Humanos , Hiperplasia , Pessoa de Meia-Idade , Recidiva
6.
J Am Coll Cardiol ; 20(3): 623-32, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1512342

RESUMO

OBJECTIVES: This study evaluates the incidence of restenosis after successful directional coronary atherectomy and identifies risk factors for restenosis. BACKGROUND: Directional coronary atherectomy has been shown to be a safe and effective treatment of obstructive coronary artery disease; however, information regarding restenosis is limited. METHODS: Between October 1986 and December 1989, 289 patients with 332 lesions were successfully treated with directional coronary atherectomy and followed up prospectively. Clinical follow-up information was available for 98% and angiographic follow-up information was obtained for 82% at approximately 6 months, or earlier if symptoms recurred. Angiograms were quantitatively analyzed. Restenosis was defined as greater than 50% stenosis at the site of intervention. RESULTS: Seventy-four percent of patients were either asymptomatic or clinically improved after the procedure. Thirty-two percent were subsequently treated by coronary artery bypass surgery (14%), percutaneous transluminal coronary angioplasty (4%) or repeat atherectomy (13%). Angiographic evidence of restenosis was observed in 42%. The restenosis rate in native coronary arteries was 31% for primary lesions and 28% and 49%, respectively, for lesions treated with one or two previous angioplasty procedures. The restenosis rate for saphenous vein grafts was 53% for primary lesions and 58% and 82%, respectively, for lesions treated with one or two previous angioplasty procedures. The median interval to angiographically documented restenosis was 133 days. A higher restenosis rate was associated with a saphenous vein graft, hypertension, a longer lesion (greater than or equal to 10 mm), a smaller vessel diameter (less than 3 mm), a noncalcified lesion and use of a smaller (6F) device. CONCLUSIONS: Restenosis remains a limitation of directional coronary atherectomy. A subset of patients with larger vessels, shorter lesions or lesions treated with a larger (7F) device may have a more favorable outcome.


Assuntos
Cateterismo Cardíaco/métodos , Doença da Artéria Coronariana/cirurgia , Vasos Coronários/cirurgia , Idoso , Prótese Vascular , Doença da Artéria Coronariana/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Veia Safena/cirurgia , Resultado do Tratamento
7.
J Am Coll Cardiol ; 17(5): 1112-20, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2007710

RESUMO

Directional coronary atherectomy, a new transluminal procedure for treatment of obstructive lesions in coronary arteries by excision and removal of tissue, was performed on 447 lesions in 382 procedures. Successful outcome, defined as a reduction of stenosis by greater than or equal to 20% with a less than 50% residual stenosis, was achieved in 89.5% of lesions and mean stenosis was reduced from 75.9 +/- 13.3% to 14.5 +/- 22.1% (p less than 0.001). Complications included vessel occlusion during the procedure, 2.4%; vessel occlusion after the procedure, 1.3%; new lesion, 0.5%; nonobstructive guiding catheter-induced dissection, 0.3%; perforation, 0.8%; distal embolization, 2.1%; Q wave myocardial infarction, 0.8% and non-Q wave myocardial infarction, 4.2%. Twelve patients (3.1%) required coronary artery bypass surgery for these complications. The atherectomy success rate was greater than 80% and the combined atherectomy and angioplasty success rate was greater than 90% for complex morphologic features such as eccentric lesions, lengthy lesions, lesions with abnormal contour, angulated lesions, ostial lesions and lesions with branch involvement. In the presence of calcific deposition, atherectomy success rate was 52% for primary lesions and 83% for restenosed lesions. Among angiographically complex lesions, calcium was the predictor for failed atherectomy (p less than 0.0001). In summary, directional coronary atherectomy is safe and effective for treatment of obstructive lesions in coronary arteries in selected cases. In particular, it achieves a high success rate in lesions with complex morphologic characteristics, such as eccentricity, abnormal contour and ostial involvement.


Assuntos
Angioplastia Coronária com Balão/métodos , Doença da Artéria Coronariana/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia Coronária com Balão/efeitos adversos , Cineangiografia , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
J Am Coll Cardiol ; 26(6): 1494-500, 1995 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7594076

RESUMO

OBJECTIVES: This study sought to assess the incidence and consequences of abrupt closure in a series of patients undergoing directional coronary atherectomy versus percutaneous coronary angioplasty. BACKGROUND: Abrupt closure with coronary angioplasty has been associated with adverse outcome. The results from the Coronary Angioplasty Versus Excisional Atherectomy Trial (CAVEAT) I, a randomized trial of coronary angioplasty versus directional coronary atherectomy, were analyzed. METHOD: This multicenter trial enrolled 1,012 patients from 1991 to 1992. All records from patients with abrupt closure, which was coded as a discrete complication, were reviewed. RESULTS: Abrupt closure occurred in 60 patients (5.9%) and was associated with a significantly longer hospital stay (median 8 vs. 3 days). Severe proximal target vessel tortuosity was more common in patients with abrupt closure (20.3% vs. 11.6%, p = 0.046), as was preexistent coronary artery thrombus (30.5% vs. 18.3%, p = 0.02). Abrupt closure was associated with a marked increase in subsequent complications (myocardial infarction 46.7% vs. 2.1%, emergency bypass surgery 38.3% vs. 0.32%, death 33% vs. 0%) and occurred more frequently in the directional coronary atherectomy group (8.0% vs. 3.8%, p = 0.005). In the coronary angioplasty group, the occlusion usually occurred at the target lesion (91%), presumably related to the effects of barotrauma. In the directional coronary atherectomy group, the site of the occlusion was the target lesion in only 58% (p = 0.045). The remaining occlusions related to problems with the technique (guide catheter or nose cone trauma), reflecting the fact that directional coronary atherectomy is a more complex procedure. CONCLUSIONS: Abrupt closure remains the principal determinant of adverse outcome after percutaneous procedures for the treatment of coronary artery disease. Although abrupt closure is more common with directional atherectomy than angioplasty, the sequelae are similar.


Assuntos
Angioplastia Coronária com Balão/efeitos adversos , Aterectomia Coronária/efeitos adversos , Infarto do Miocárdio/etiologia , Idoso , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/fisiopatologia , Estudos Prospectivos , Resultado do Tratamento
9.
J Am Coll Cardiol ; 6(3): 526-33, 1985 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3161923

RESUMO

The influence of multiple clinical, angiographic and technical variables on the outcome of percutaneous transluminal coronary angioplasty was evaluated in a group of 76 consecutive patients with total coronary artery occlusion. Angioplasty was performed successfully in 53% of these patients. The likelihood of successful angioplasty was favorably influenced by: 1) a history of prior myocardial infarction in the distribution of the occluded arterial segment (p = 0.03); 2) an estimated maximal duration of arterial occlusion of less than 20 weeks (p less than 0.001); and 3) a length of nonvisualized arterial segment distal to the point of occlusion of less than 1.5 cm (p = 0.03). The outcome of coronary angioplasty was not significantly influenced by the vessel involved, the location of the occlusion within an involved vessel, the morphology of the occlusion (tapered versus abrupt) or the age and sex of the patient. There were no deaths and no vascular perforations. Four patients had recurrent coronary occlusion within 24 hours of the procedure; in three of these, recurrent occlusion was successfully treated with reangioplasty and in one, emergent surgical revascularization was performed. Embolic occlusion of an arterial branch distal to the point of total coronary occlusion occurred in 4 of the 40 successfully recanalized arteries. Seventy-five percent of patients having successful recanalization of an occluded coronary artery were free of the anginal symptoms that had prompted performance of the procedure at a mean follow-up period of 7.3 months. Thus, angioplasty of a total coronary artery occlusion can be performed safely and effectively, particularly in patients with a history of prior myocardial infarction, a brief estimated duration of coronary occlusion and a short nonvisualized occluded arterial segment.


Assuntos
Angioplastia com Balão , Arteriopatias Oclusivas/terapia , Doença das Coronárias/terapia , Adulto , Fatores Etários , Idoso , Angiografia Coronária , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores Sexuais , Fatores de Tempo
10.
Cardiovasc Res ; 32(3): 496-502, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8881510

RESUMO

OBJECTIVES: Collagen synthesis is one of the major mechanisms of primary atherosclerotic plaque growth and is likely to be similarly important in restenosis. The patterns of collagen gene expression in human restenosis and associations with thrombosis/hemorrhage have not been described. METHODS: Using human coronary artery samples obtained via the atherectomy catheter, we compared primary plaques (40 specimens) and restenotic lesions (41 specimens) for type I collagen gene expression using immunocytochemistry (SPI.D8 antibody to type I procollagen, an intracellular precursor of mature collagen) with subsequent computer image analysis. RESULTS: Scattered positive cells were identified in specific, non-random patterns. According to logistic regression analyses, type I procollagen gene expression seems to be more closely associated with certain morphological features (organized thrombus, microvessels, regions enriched with stellate cells) than with belonging to a primary vs. a restenotic sample. However, there may be a tendency for restenotic tissue to have slightly higher numbers of type I procollagen-positive cells than primary lesion tissue. CONCLUSIONS: Symptomatic primary and restenotic lesions exhibit similar patterns of type I collagen gene expression. Plaque microvessels and thrombi/hemorrhages (common features of both kinds of advanced lesions) might stimulate collagen synthesis equally well irrelevant to the nature of the lesion.


Assuntos
Colágeno/genética , Doença da Artéria Coronariana/metabolismo , Vasos Coronários/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pró-Colágeno/genética , Recidiva , Análise de Regressão , Gânglio Estrelado/patologia
11.
Atherosclerosis ; 152(1): 117-26, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10996346

RESUMO

Previously, we demonstrated that replication in restenotic coronary atherectomy specimens was an infrequent and modest event. In general, this data was interpreted with caution, as immunocytochemistry for the proliferating cell nuclear antigen (PCNA) was used to subjectively assess proliferation and most of the tissue specimens were resected more than 3 months after the initial interventional procedure. The purpose of the present study was to use a more sensitive method of detecting replication, in situ hybridization for histone 3 (H3) mRNA, to determine the replication profile of human directional atherectomy specimens. Restenotic directional coronary atherectomy specimens from lesions that had undergone an interventional procedure within the preceding 3 months were studied. In addition, larger atherectomy specimens from peripheral arterial lesions were assessed to ensure that pockets of replication were not being overlooked in the smaller coronary specimens. We found evidence for replication in tissue resected from 2/17 coronary and 9/12 peripheral artery restenotic lesions. In contrast, 3/11 specimens resected from primary lesions of peripheral arteries also expressed H3 mRNA. We estimated that the maximum percentage of cells that were replicating in restenotic coronary, restenotic peripheral and primary peripheral artery tissue slides to be <0.5, < or =1.2 and <0.01%, respectively. Replication was found in tissue specimens resected both early and late after a previous interventional procedure. For specimens with >15 replicating cells per slide we found high levels of focal replication. Therefore, cell replication, as assessed by the expression of H3 mRNA, was infrequent in restenotic coronary artery specimens, whereas peripheral restenotic lesions had more frequent and higher levels of replication regardless of the interval from the previous interventional procedure. For all specimens the percentage of cells that were replicating was low, however focal areas with relatively high replication indices were presented. Although replication was more abundant in restenotic lesions it does not appear to be a dominant event in the pathophysiology of restenosis.


Assuntos
Doença da Artéria Coronariana/patologia , Doença das Coronárias/patologia , Músculo Liso Vascular/patologia , RNA Mensageiro/análise , Adulto , Idoso , Aterectomia , Divisão Celular , Doença da Artéria Coronariana/cirurgia , Técnicas de Cultura , Endotélio Vascular/patologia , Feminino , Histonas/genética , Humanos , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/citologia , Probabilidade , Recidiva , Valores de Referência , Sensibilidade e Especificidade
12.
Am J Cardiol ; 53(12): 94C-96C, 1984 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-6233898

RESUMO

Since the introduction in 1979 of a movable guidewire system for PTCA, significant advances have been made in guidewire technology that have improved primary success rates and reduced complications with the use of this system. Coronary stenoses in distal sites or in branch vessels with abrupt angulations can now routinely be reached and crossed with newer-generation guidewires . This report concentrates on the evolution of advances in guidewire technology and outlines changes in guidewire design that have allowed for improved efficacy and safety with the movable wire system. Appropriate cases are presented to illustrate the advantages of available guidewires .


Assuntos
Angioplastia com Balão/instrumentação , Vasos Coronários , Angiografia Coronária , Humanos
13.
Am J Cardiol ; 72(13): 30E-34E, 1993 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-8213567

RESUMO

Directional coronary atherectomy (DCA) of saphenous vein graft lesions was performed at 21 centers between June 1988 and September 1990, which represents the multicenter investigational experience. A total of 318 procedures were performed and 363 vein graft lesions were treated. Angiographic success with DCA was achieved in 86% of lesions and clinical success was achieved in 85% (269 of 318) of patients. Major complications occurred in 2.5% of patients, with Q wave myocardial infarction (MI) in 1.3%, death in 0.9%, and urgent bypass surgery in 0.9%. Other complications included non-Q wave MI in 4.4%, distal embolization in 7.2%, coronary occlusion in 1.9%, and vessel perforation in 0.6%. Although there was a trend toward lower success rates with ostial vein graft lesions (82% vs 88% for other graft sites) and with diffuse (length > 20 mm) graft lesions (75% vs 87% for shorter lesions), the differences were not significant. Baseline clinical and angiographic factors did not identify predictors of lower success or more frequent complications in the study group. Overall restenosis rate in the 149 patients with angiographic restudy was 57%. The restenosis rate was significantly lower with primary vein graft lesions (38%) compared with a 75% restenosis rate for grafts with prior restenosis, p < 0.001. This initial multicenter investigational experience indicates that directional coronary atherectomy is a safe and effective therapy for selected saphenous vein graft disease. Although the overall restenosis rate is relatively high, the restenosis rate following DCA of primary vein graft lesions is significantly lower than for vein grafts having had prior intervention.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Aterectomia Coronária , Oclusão de Enxerto Vascular/cirurgia , Aterectomia Coronária/efeitos adversos , Aterectomia Coronária/estatística & dados numéricos , Angiografia Coronária , Feminino , Oclusão de Enxerto Vascular/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Recidiva , Veia Safena/transplante , Estados Unidos , United States Food and Drug Administration
14.
Am J Cardiol ; 49(5): 1216-22, 1982 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-6461241

RESUMO

A new catheter system has been designed for percutaneous transluminal coronary angioplasty. An independently movable, flexible-tipped guide wire within the balloon dilation catheter facilitates selection of the involved vessel. This guide wire can be passed slowly and carefully beyond the coronary stenosis, permitting safe advancement of the balloon catheter. After testing in animal and cadaver hearts, this system was used in 53 patients (56 stenoses) with single vessel coronary artery disease, with an overall primary success rate of 64 percent. In the last 41 of these 56 cases, use of a balloon catheter with a smaller deflated diameter increased the success rate to 73 percent. In patients with lesions of the left anterior descending coronary artery, the success rate was 89 percent. Three (6 percent) of the 53 patients had complications during coronary arterial dilation that necessitated emergency coronary arterial bypass graft surgery. There were no procedure-related or late cardiac deaths. During the mean follow-up period of 8 months (range 1 to 21), there were one late death (of noncardiac causes) and no late myocardial infarctions. Clinical status was persistently improved in 31 of the 36 patients who had successful dilation. The remaining five patients experienced restenosis at the angioplasty site and return of angina pectoris within 3 months of dilation. Two of these patients had repeat coronary angioplasty with restoration of asymptomatic status, and three had elective coronary bypass graft surgery.


Assuntos
Angioplastia com Balão/instrumentação , Vasos Coronários , Cateterismo Cardíaco/instrumentação , Doença das Coronárias/terapia , Seguimentos , Humanos
15.
Am J Cardiol ; 61(14): 96G-101G, 1988 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-2966573

RESUMO

Sixty-one patients with occlusive peripheral vascular disease were treated with transluminal atherectomy, a catheter-mediated technique for removal of atheroma. The technique was performed using 7Fr, 9Fr or 11Fr atherectomy catheters. Mean percent diameter stenosis was reduced from 71 to 23%, by removal of 831 atheromatous specimens in 949 passes of the cutting element through 136 stenoses in 61 patients. All specimens removed were sent for histopathologic examination to determine the components of the atheroma removed, which differed for specimens removed from original vs restenotic lesions. Percent stenosis was reduced to less than 45% in 118 of 136 stenoses (87%). Complications included 1 thrombus, which resolved after intraarterial infusion of streptokinase and 1 probable distal embolization without sequelae. Three angiographic dissections occurred without impairment of blood flow. There were no instances of acute occlusion, vascular spasm or vessel perforation. Six-month follow-up angiography was performed showing that patients who had a residual stenosis less than 30% after initial atherectomy had a lower restenosis rate (18%) than patients with initial residual stenoses greater than 30% (52%); this result demonstrated the importance of performing more complete atherectomy. Transluminal atherectomy appears to be an effective, predictable and safe method for removing occlusive atheromatous deposits from peripheral arteries.


Assuntos
Angioplastia com Balão/métodos , Arteriosclerose/terapia , Claudicação Intermitente/terapia , Angioplastia com Balão/instrumentação , Constrição Patológica/terapia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Tempo
16.
Am J Cardiol ; 72(13): 6E-11E, 1993 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-8213572

RESUMO

Between 1988 and 1990, clinical testing was performed at 12 US institutions using the Simpson Coronary AtheroCath under an Investigational Device Exemption. Data on 1,069 lesions (873 patients) were analyzed and presented to the Food and Drug Administration (FDA) advisory panel in the summer of 1990, forming the basis for approval of this device in September 1990. Analysis of these preapproval data shows a primary success rate of 85% (defined as tissue removal, > or = 20% reduction in stenosis, < 50% residual stenosis after directional atherectomy, and no major complication), with somewhat higher primary success in prior restenosis and noncalcified lesions. Including the use of conventional angioplasty performed after atherectomy, the overall success rate was 92%. One or more major complications occurred in 4.9% of procedures, and included death (0.5%), nonfatal Q-wave myocardial infarction (0.9%), and emergency bypass surgery (4.0%). These complications were more frequent in right coronary, de novo, and diffuse (> 20-mm length) lesions. Six-month angiography results were available in 384 (77%) of 498 lesions eligible for follow-up when the registry closed and showed a restenosis rate (late stenosis > 50%) of 42%. The restenosis rate in both native vessels (30 vs 46%) and bypass grafts (31 vs 68%) was lower in primary (de novo) lesions compared with lesions that had developed restenosis after a prior intervention. Despite the use of prototype atherectomy catheters and still evolving procedural technique, this preapproval experience provided an important initial indication of the situations in which directional coronary atherectomy was most useful and helped set clear standards for performance of this procedure following FDA approval.


Assuntos
Aterectomia Coronária , Doença da Artéria Coronariana/cirurgia , Oclusão de Enxerto Vascular/cirurgia , Aterectomia Coronária/efeitos adversos , Aterectomia Coronária/instrumentação , Aterectomia Coronária/estatística & dados numéricos , Angiografia Coronária , Doença da Artéria Coronariana/epidemiologia , Desenho de Equipamento , Seguimentos , Oclusão de Enxerto Vascular/epidemiologia , Humanos , Recidiva , Sistema de Registros , Estados Unidos/epidemiologia , United States Food and Drug Administration
17.
Am J Cardiol ; 72(13): 80E-87E, 1993 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-8213575

RESUMO

Histologic analysis of atherectomy samples from > 400 patients who received directional coronary atherectomy at 3 separate institutions disclosed 2 major categories of tissue: atherosclerotic plaque (with or without thrombus) and intimal proliferation (hyperplasia, with or without thrombus). The predominant tissue type in atherectomy samples from native, primary, or de novo coronary artery stenoses was atherosclerotic plaque. The predominant tissue type in atherectomy samples from restenosis lesions (prior balloon angioplasty, atherectomy, or both) was intimal proliferation with variable amounts of atherosclerotic plaques (with or without thrombus). Deep vessel wall components (media, adventitia) were identified at varying frequencies. The clinical relevance of atherectomy tissue is reviewed.


Assuntos
Aterectomia Coronária , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Doença da Artéria Coronariana/cirurgia , Trombose Coronária/patologia , Feminino , Humanos , Hiperplasia , Masculino , Pessoa de Meia-Idade , Recidiva , Túnica Íntima/patologia
18.
Am J Cardiol ; 66(1): 49-53, 1990 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-2360533

RESUMO

Directional coronary atherectomy is a new percutaneous transluminal technique for treating occlusive coronary artery disease. In this study, angiographic results (i.e., residual stenosis and angiographic evidence of postprocedure dissection) after directional coronary atherectomy and balloon angioplasty were compared. The atherectomy group consisted of 91 lesions in 83 consecutive patients who underwent either left anterior descending artery or right coronary artery atherectomy. The angioplasty group consisted of 91 lesions in 84 patients that were matched with the atherectomy lesions with respect to vessel and whether the lesion was a restenosis lesion. The mean preprocedure diameter stenosis was 76% in both groups as measured quantitatively with electronic calipers. After the procedure, the mean residual diameter stenosis of the atherectomy lesions was 13 +/- 17%, whereas for the angioplasty lesions it was 31 +/- 18% (p less than 0.001). Success rates in both groups were similar (94.5 and 93.4%, respectively). The incidence of postprocedure dissection was 11% in the atherectomy group and 37% in the angioplasty group (p less than 0.0001). Directional coronary atherectomy results in significantly improved postprocedure angiographic appearances due to significantly less severe residual stenosis and lower incidence of dissection.


Assuntos
Angioplastia Coronária com Balão , Doença da Artéria Coronariana/terapia , Vasos Coronários/lesões , Angioplastia Coronária com Balão/efeitos adversos , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/cirurgia , Vasos Coronários/patologia , Humanos , Pessoa de Meia-Idade , Grau de Desobstrução Vascular
19.
Am J Cardiol ; 70(13): 1101-8, 1992 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-1414929

RESUMO

In comparing the restenosis rates among different interventions, 1 potential confounder might be the differences in the vessels treated, as dictated by the technical limitations of particular devices. The purpose of this study was to use current "acute gain-late loss" analysis to examine what influence vessel selection has on the restenosis rates seen after coronary stenting or directional atherectomy. The minimal luminal diameter of native coronary lesions was measured before and immediately after intervention in 102 single Palmaz-Schatz stents and 347 atherectomies, 367 (82%) of which had repeat angiographic measurement 6 months after intervention. Atherectomy-treated lesions had a higher proportion of left anterior descending to right coronary arteries (68 vs 24%) compared with stents (31 vs 54%), p < 0.001. Although subsequent restenosis rates were similar for stenting (25%) and atherectomy (30%, p = 0.42), left anterior descending versus right coronary lesions had a significantly higher restenosis rate for the overall group (35 vs 18%, p = 0.009), for stents (44 vs 13%, p = 0.008) and for atherectomy (35 vs 22%, p = 0.10), respectively. Multivariable analysis demonstrated that postprocedure luminal diameter (p = 0.03, p = 0.009) and coronary location (the proportion of left anterior descending vessels treated, p = 0.002, p < 0.001), but not device type (stent vs atherectomy), were strong independent determinants of restenosis according to both binary (> 50% diameter stenosis) and continuous (late percent stenosis) definitions.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Aterectomia Coronária , Doença das Coronárias/cirurgia , Stents , Idoso , Aterectomia Coronária/métodos , Distribuição de Qui-Quadrado , Constrição Patológica/cirurgia , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva , Análise de Regressão
20.
Behav Neurosci ; 104(4): 637-42, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2206433

RESUMO

The effects of subfornical organ (SFO) lesions on salt and water intakes after sodium depletion were studied. Water and salt intakes were measured over 45 hr during a regimen that combined furosemide diuresis and access to low-sodium diet. Water was solely available for 23 hr after diuresis, and water and 0.3 M NaCl solution were available in choice for the next 22 hr. After diuresis, rats with SFO lesions drank significantly less water in 2 hr than controls but achieved equivalent water and sodium balances before salt access 20 hr later. After salt access, rats with SFO lesions drank significantly less saline and water in 2 hr than controls but had similar saline and water intakes over the next 20 hr. Thus, SFO lesions blunted acutely, but not chronically, saline and water intakes to sodium depletion, and the blunted intakes are not explainable by hydrational status.


Assuntos
Apetite/fisiologia , Sódio na Dieta , Órgão Subfornical/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Animais , Mapeamento Encefálico , Masculino , Ratos , Ratos Endogâmicos , Sede/fisiologia
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