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1.
Am J Cardiol ; 83(8): 1296-9, A10, 1999 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10215306

RESUMO

Moyamoya is a vascular occlusive disease typically limited to the cerebral arterial system. We report a case of severe stenosis of the left main and right coronary arteries occurring in association with moyamoya disease, supporting the concept that moyamoya may be an intracranial manifestation of a systemic arterial disorder.


Assuntos
Doença das Coronárias/etiologia , Doença de Moyamoya/complicações , Adulto , Angioplastia Coronária com Balão , Angiografia Cerebral , Angiografia Coronária , Ponte de Artéria Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/cirurgia , Diagnóstico Diferencial , Seguimentos , Humanos , Masculino , Doença de Moyamoya/diagnóstico , Recidiva
2.
Circulation ; 86(5): 1383-93, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1423950

RESUMO

BACKGROUND: High-speed rotational atherectomy uses a diamond-coated, elliptical burr to abrade occlusive atherosclerosis, especially noncompliant calcified plaque. METHODS AND RESULTS: Intravascular ultrasound (IVUS) was used to analyze 28 patients after atherectomy. Arteries treated and imaged were left main (three), left anterior descending (12), left circumflex (five), right coronary (seven), and saphenous vein graft (one). Twenty patients had adjunct balloon angioplasty. Twenty-two (79%) target lesions were calcified; the intimal arc of calcium was 160 +/- 126 degrees (range, 0-360 degrees). After atherectomy, the intima-lumen interface was unusually distinct and circular. The lumen was larger than the largest burr used for both stand-alone (1.19 +/- 0.19-fold the largest burr size) and adjunct balloon procedures (1.30 +/- 0.15-fold the largest burr). Three-dimensional reconstruction of the ultrasound images showed a smooth lumen, especially in calcified plaque. Deviations from cylindrical geometry occurred only in areas of soft plaque or superficial tissue disruption of calcified plaque. Five patients were studied before and after rotational atherectomy. IVUS showed an increase in lumen size, a decrease in plaque-plus-media area and in arc of target lesion calcification, and no change in target lesion external elastic membrane cross-sectional area. CONCLUSIONS: Rotational atherectomy causes atheroablation with only moderate evidence of barotrauma in heavily calcified arteries, even after adjunct balloon angioplasty. The lumen is cylindrical, especially in areas of calcified plaque, and somewhat larger than the largest burr tip used.


Assuntos
Aterectomia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Angioplastia Coronária com Balão , Terapia Combinada , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Ultrassonografia
3.
J Am Coll Cardiol ; 20(4): 942-51, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1527306

RESUMO

OBJECTIVES: The purpose of this study was to examine the coronary artery response to percutaneous transluminal coronary angioplasty by using intravascular ultrasound. BACKGROUND: The immediate effects of coronary angioplasty on arterial wall geometry and surface appearance are understood poorly. Most of the available data are derived from small necropsy series, inferred from animal models or extrapolated from in vitro studies. High frequency intravascular ultrasound provides transmural images of coronary arteries in vivo. METHODS: We used intravascular ultrasound to study 29 patients before or after, or both, successful coronary angioplasty. RESULTS: The angiographic diameter narrowing was 72 +/- 13% before and improved to 19 +/- 11% after angioplasty. Calcium was visualized in 7 (24%) of the 29 angioplasty sites by fluoroscopy versus 15 (52%) of sites by intravascular ultrasound (p = 0.022). Arterial dissection after angioplasty was observed in 8 (27%) of cases by contrast angiography versus 24 (83%) by intravascular ultrasound (p less than 0.001). Intravascular ultrasound detected extensive dissection at the angioplasty site in 11 (73%) of the 15 calcified plaques and in only 3 (21%) of the 14 noncalcified plaques (p = 0.024). Arterial expansion (defined as the area within the external elastic membrane at the angioplasty site greater than that of the proximal reference segment) occurred in 29% of calcified plaques compared with 86% of noncalcified plaques (p = 0.007). CONCLUSIONS: Intravascular ultrasound is more sensitive than angiography for identifying arterial calcium and dissection at the site of angioplasty. At the site of angioplasty, arterial dissection occurred more frequently in calcified plaques whereas arterial expansion occurred more frequently in noncalcified plaques. Successful angioplasty causes a continuum of arterial responses that vary importantly with plaque composition.


Assuntos
Angioplastia Coronária com Balão , Doença da Artéria Coronariana/terapia , Vasos Coronários/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Calcinose/terapia , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Ultrassonografia/métodos
6.
Eur Heart J ; 13(1): 102-8, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1577016

RESUMO

This paper presents our experience with intravascular ultrasound imaging of animal and human arteries in vitro and in vivo using a high-frequency (20 M Hz) ultrasound transducer. In vitro, 32 human coronary artery segments were imaged with intravascular ultrasound and compared with corresponding histological sections. Ultrasound and histology measurements correlated significantly (P less than 0.0001) for coronary artery cross-sectional area (r = 0.94), lumen cross-sectional area (r = 0.85) and wall thickness (r = 0.92). In vivo, 19 sheep and eight human common femoral arteries were imaged and the angiographic lumen diameter of 14 animal and six human arteries was compared to the diameter of the corresponding ultrasound images. Significant correlations were found for lumen diameter in animals and humans (P less than 0.001, r = 0.91 and P less than 0.0001, r = 0.96, respectively). These studies demonstrate that this technique can provide high resolution images of arterial vessels and may have unique advantages in diagnosing atherosclerotic vascular disease and in catheter based therapies.


Assuntos
Artérias/diagnóstico por imagem , Ultrassonografia/instrumentação , Adulto , Idoso , Animais , Artérias/anatomia & histologia , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Ovinos
7.
Am J Card Imaging ; 5(1): 60-4, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10147586

RESUMO

Recent in vitro studies have demonstrated that intravascular ultrasound can obtain high-resolution cross-sectional images of arterial vessels. To further expand the use of this technique for in vivo visualization of peripheral and coronary vessels, we imaged 24 femoral and 13 carotid arteries from 19 sheep. Using a manual rotation technique, high-resolution images were obtained in 95% of the vessel sites with a rigid probe and in 82% of the vessel sites with a flexible catheter. In 14 of these arteries, good correlation was found between the lumen diameter measured by ultrasound and by angiography (P less than .001, r = .91). In addition, 6 left circumflex coronary arteries were imaged from 6 additional sheep by motor-driven rotation of the ultrasound probe at 1,800 rotations per minute, obtaining clear delineation of coronary lumen morphology and lumen-intima interface. Strong correlation was found also between intravascular ultrasound and cineangiography for coronary artery diameter measurement (P less than .001, r = .96). These studies demonstrate that this technique can provide high-resolution images of arterial vessels in vivo and may have unique advantages in diagnosis of atherosclerotic vascular disease and in the guidance of new catheter-based therapeutic modalities.


Assuntos
Arteriosclerose/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Artéria Femoral/diagnóstico por imagem , Animais , Arteriosclerose/terapia , Cineangiografia , Estudos de Avaliação como Assunto , Ovinos , Ultrassonografia
9.
Echocardiography ; 7(4): 389-95, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10149202

RESUMO

Intravascular ultrasound provides cross-sectional images of arteries and enables accurate delineation of lumen dimensions and wall structure. Moreover, ultrasound characterization of atherosclerotic plaque subtypes may have important implications in determining the natural history and the clinical outcome of patients with coronary artery disease. The reliability of intravascular ultrasound to differentiate plaque morphology subtypes was studied in 60 coronary segments excised from 33 coronary arteries obtained from 17 patients at necropsy. Ultrasound was performed with a 25-MHz transducer mounted on the distal end of a rigid probe that was rotated manually inside the lumen artery. Plane film radiography was also performed to establish the presence of calcific deposits. A total of 82 histologic transverse sections corresponding to 82 ultrasound imaging sites were studied from the 60 coronary segments. Of the first 54 images, 36 were fibrous plaques and yielded dense homogenous echo reflections, 6 had discrete areas of lipid that were less echogenic and 12 had calcific deposits that cast echo-free shadows beyond areas of intense echo reflections. The predictive accuracy of evaluating plaque composition in the remaining 28 ultrasound imaging sites was 96%. Thus, anatomical structure of coronary arteries and composition of atherosclerotic lesions can be assessed accurately with intravascular ultrasound and may have potential for better understanding of the atherosclerotic process and provide guidance to interventional procedures.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/patologia , Idoso , Idoso de 80 Anos ou mais , Doença da Artéria Coronariana/patologia , Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transdutores , Ultrassonografia/instrumentação , Ultrassonografia/métodos
10.
Circulation ; 81(5): 1575-85, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2184946

RESUMO

Safe and effective clinical application of new interventional therapies may require more precise imaging of atherosclerotic coronary arteries. To determine the reliability of catheter-based intravascular ultrasound as an imaging modality, a miniaturized prototype ultrasound system (1-mm transducer; center frequency, 25 MHz) was used to acquire two-dimensional, cross-sectional images in 21 human coronary arteries from 13 patients studied at necropsy who had moderate-to-severe atherosclerosis. Fifty-four atherosclerotic sites imagined by ultrasound were compared with formalin-fixed and fresh histological sections of the coronary arteries with a digital video planimetry system. Ultrasound and histological measurements correlated significantly (all p less than 0.0001) for coronary artery cross-sectional area (r = 0.94), residual lumen cross-sectional area (r = 0.85), percent cross-sectional area (r = 0.84), and linear wall thickness (plaque and media) measured at 0 degrees, 90 degrees, 180 degrees, and 270 degrees (r = 0.92). Moreover, ultrasound accurately predicted histological plaque composition in 96% of cases. Anatomic features of the coronary arteries that were easily discernible were the lumen-plaque and media-adventitia interfaces, very bright echoes casting acoustic shadows in calcified plaques, bright and homogeneous echoes in fibrous plaques, and relatively echo-lucent images in lipid-filled lesions. These data indicate that intravascular ultrasound provides accurate image characterization of the artery lumen and wall geometry as well as the presence, distribution, and histological type of atherosclerotic plaque. Thus, ultrasound imaging appears to have great potential application for enhanced diagnosis of coronary atherosclerosis and may serve to guide new catheter-based techniques in the treatment of coronary artery disease.


Assuntos
Vasos Coronários/patologia , Ultrassonografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença da Artéria Coronariana/diagnóstico , Feminino , Fixadores , Formaldeído , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia/instrumentação
11.
Echocardiography ; 7(3): 181-92, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-10171129

RESUMO

In this paper we review the current status of intravascular ultrasound. Data from qualitative and quantitative studies is presented. Our experimental findings and those of other investigators are reviewed. Intravascular ultrasound has been shown to delineate normal and abnormal arterial morphology as well as to identify and differentiate fibrous, lipid-rich, calcified plaques and complicated plaques. Quantitative studies show strong correlations between ultrasound and histology for lumen area, wall thickness, and plaque area. In vivo studies from our experimental work and clinical laboratory as well as the work of other researchers is presented. This data supports the potential of ultrasound imaging for guidance of intravascular intervention. The potential advantages and limitations of this new technology are discussed. This methodology shows promise for the assessment of the extent and severity of atherosclerosis, monitoring its progression and regression and guiding intravascular plaque ablation technologies.


Assuntos
Arteriosclerose/diagnóstico por imagem , Animais , Artérias/diagnóstico por imagem , Artérias/patologia , Arteriosclerose/terapia , Cães , Previsões , Humanos , Monitorização Intraoperatória , Suínos , Ultrassonografia/métodos , Ultrassonografia/tendências
12.
J Am Coll Cardiol ; 15(1): 196-203, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2136873

RESUMO

Mode of death, frequency of a healed or an acute myocardial infarct, or both, number of major epicardial coronary arteries severely narrowed by atherosclerotic plaque, and heart weight were studied at necropsy in 889 patients 30 years of age or older with fatal atherosclerotic coronary artery disease. No patient had had a coronary bypass operation or coronary angioplasty. The 889 patients were classified into four major groups and each major group was classified into two subgroups: 1) acute myocardial infarct without (306 patients) or with (119 patients) a healed myocardial infarct; 2) sudden out of hospital death without (121 patients) or with (118 patients) a healed myocardial infarct; 3) chronic congestive heart failure with a healed myocardial infarct without (137 patients) or with (33 patients) a left ventricular aneurysm; and 4) sudden in-hospital death without (20 patients) or with (35 patients) unstable angina pectoris. The mean age of the 687 men (77%) was 60 +/- 11 years, and of the 202 women (23%), 68 +/- 13 years (p = 0.0001). Although men included 77% of all patients, they made up approximately 90% of the out of hospital (nonangina) sudden death group. The frequency of systemic hypertension and angina pectoris was similar in each of the four major groups. The frequency of diabetes mellitus was least in the sudden out of hospital death group and similar in the other three major groups. The mean heart weight and the percent of patients with a heart of increased weight were highest in the chronic congestive heart failure group; values were lower and similar in the other three major groups.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Infarto do Miocárdio/patologia , Miocárdio/patologia , Cardiomegalia/patologia , Causas de Morte , Doença da Artéria Coronariana/mortalidade , Morte Súbita/patologia , Feminino , Aneurisma Cardíaco/patologia , Insuficiência Cardíaca/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão
13.
Am J Surg ; 158(2): 142-5, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2667386

RESUMO

Increasingly complex vascular reconstructions and emerging endovascular therapeutic modalities have stimulated the need for improved vascular imaging. To determine the feasibility of in vivo intravascular ultrasound, a miniature probe 1 mm in diameter with a 25 MHz center frequency was used to obtain two-dimensional, 360-degree cross-sectional images. In sheep, 14 superficial femoral arteries were imaged at different sites, and a portion of each vessel was resected for immediate in vitro imaging and histologic examination. In vivo images clearly showed the intima, media, and adventitia of the vessel wall as well as the lumen-intima and media-adventitia interfaces. There was a significant correlation in measured lumen area between resected artery ultrasound images and histologic sections. We conclude that intravascular ultrasound can produce high-resolution dynamic images that demonstrate vessel wall architecture and allow precise calculation of lumen area.


Assuntos
Artéria Femoral/anatomia & histologia , Ultrassonografia , Animais , Estudos de Viabilidade , Ovinos
14.
Am J Cardiol ; 62(16): 1017-23, 1988 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-2973216

RESUMO

To determine the relation of a single healed myocardial infarct to a fatal acute myocardial infarct, 129 patients with 1 grossly visible healed and 1 grossly visible acute infarct were studied at necropsy. It was determined whether the acute infarct was opposite to or adjacent to the healed infarct or if 1 infarct was so large that it was both opposite to and adjacent to the other infarct. In 74 (57%) of the 129 patients, the 2 infarcts were opposite one another, in 40 (31%) they were adjacent and in 15 (12%) they were both opposite and adjacent. The age, sex, mean size of the healed infarct and heart weight were similar among the 3 groups. Acute myocardial infarcts were larger in the group that had both opposite and adjacent infarcts than either of the other 2 groups (p less than 0.001). Information regarding whether the infarcts were clinically recognized or not was available in 108 patients: both infarcts were recognized in 41 (38%), neither infarct was recognized in 15 (14%) and 1 infarct was recognized and the other was not in 52 (48%). The number of the 4 major epicardial coronary arteries narrowed at some point greater than 75% in cross-sectional area by atherosclerotic plaque was similar in patients with recognized and in those with unrecognized infarcts. Similar numbers of narrowed major epicardial coronary arteries also were found in each of the 3 infarct groups (opposite, adjacent or both).


Assuntos
Infarto do Miocárdio/patologia , Miocárdio/patologia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Cardiomegalia/patologia , Constrição Patológica/patologia , Vasos Coronários/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Am J Cardiol ; 62(1): 41-50, 1988 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-2968041

RESUMO

To delineate their relation to outcome of percutaneous transluminal coronary angioplasty (PTCA), the atherosclerotic plaque composition and coronary artery size in 82 five-mm long segments at 28 PTCA sites were determined in 26 patients having PTCA. The 26 patients were subdivided into 3 groups according to the degree of angiographic patency at the end of the PTCA procedure and to the duration of survival after PTCA (less than or equal to 30 or greater than 30 days): early success (13 patients, 16 PTCA sites and 49 five-mm segments); early failure (4 patients, 4 PTCA sites and 16 five-mm segments) and late success (9 patients, 8 PTCA sites and 17 five-mm segments). The mean percent of plaque comprised of fibrous tissue among the 3 groups was 80 +/- 18%, 71 +/- 23% and 82 +/- 16% (difference not significant); the mean percent of plaque comprised of lipid was 17 +/- 16%, 21 +/- 24% and 16 +/- 15% (difference not significant); and of calcium it was 3 +/- 4%, 8 +/- 10% and 2 +/- 3% (p = 0.01). The mean coronary arterial internal diameter was 3.3 +/- 0.6, 3.9 +/- 1.2 and 3.2 +/- 0.7 mm (p less than 0.02). Plaque tear was present in 1 or more histologic sections in 25 of the 26 patients and the 1 patient without it had the longest interval (nearly 3 years) between PTCA and death. Plaque tear extending from intima into media with dissection was observed only in the early and late success groups (p = 0.03). Hemorrhage into plaque was present in 16 (80%) of 20 PTCA sites in the 2 early groups and in 3 (37%) of 8 sites in the late group (p less than 0.03). Occlusive thrombus (5 of 16, 1 of 4 and 1 of 8) and plaque debris (7 of 16, 1 of 4 and 2 of 8) in residual lumens were insignificantly different among the 3 groups and their 82 five-mm segments. Plaques that had greater than 25% lipid content, however, had an increased frequency of hemorrhage into plaque (p less than 0.004), occlusive thrombus (p = 0.0001) and plaque debris in residual lumens (p less than 0.05). These findings suggest that coronary arterial size and plaque composition are strong determinants of PTCA outcome. The ideal coronary arterial atherosclerotic narrowing for both technically and clinically successful PTCA appears to be a small (less than 3.3 mm in internal diameter) artery in which the plaque contains relatively little calcium and lipid.


Assuntos
Angioplastia com Balão , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Am J Gastroenterol ; 82(6): 558-9, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3578237

RESUMO

Common complications of amebic liver abscesses include rupture into the thorax, pericardium, and peritoneum. Rupture into the gastrointestinal tract is extremely rare. We report a case of an amebic liver abscess rupturing into the duodenum, forming a wide fistulous tract. To our knowledge, this is the first case with radiological confirmation.


Assuntos
Duodenopatias/etiologia , Fístula/etiologia , Fístula Intestinal/etiologia , Abscesso Hepático Amebiano/complicações , Hepatopatias/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
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