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Journal of the American College of... May 1991Coronary angioplasty has become a successful and widely used treatment for patients with coronary artery disease since its first clinical application in 1977. The... (Review)
Review
Coronary angioplasty has become a successful and widely used treatment for patients with coronary artery disease since its first clinical application in 1977. The primary success rate has improved despite the increase in procedure and case complexity. However, acute reocclusion and late restenosis, which constitute the most important problems after successful angioplasty, continue to occur in about 5% and 35% of patients within 3 to 6 months, respectively. Angioscopic and pathologic observations have suggested that a multifactorial pathophysiologic process accounts for acute reocclusion, involving marked thrombosis, intimal dissection, medial and subintimal hemorrhage, vascular recoil and vasocontriction. In contrast, chronic restenosis involves the development of fibrocellular intimal hyperplasia within a milieu created by vascular injury, platelet activation, thrombin generation and the release of mitogens. Although current pharmacologic approaches, which involve antithrombotic and anticoagulant therapy, have been largely ineffective in eliminating acute reocclusion and chronic restenosis, recent advances in the research in thrombosis, platelet receptors and smooth muscle growth regulation have allowed new therapeutic options to be tested in the experimental setting, with subsequent potential clinical applications in patients.
Topics: Angioplasty, Balloon, Coronary; Animals; Blood Platelets; Coronary Disease; Coronary Vessels; Fibrinolytic Agents; Hemodynamics; Humans; Hyperplasia; Muscle, Smooth, Vascular; Recurrence; Thrombin; Time Factors
PubMed: 2016486
DOI: 10.1016/0735-1097(91)90942-3 -
Circulation Journal : Official Journal... Aug 2016
Comparative Study
Angioscopic Assessment of Stent Stability and Neointimal Coverage After Implantation of 2nd-Generation Drug-Eluting Stents - Comparison With Bare-Mental Stents and 1st-Generation Drug-Eluting Stents.
Topics: Angioscopy; Drug-Eluting Stents; Humans; Neointima
PubMed: 27488284
DOI: 10.1253/circj.CJ-16-0743 -
Journal of the American Heart... Sep 2021Background Current guidelines recommend at least 6 months of antithrombotic therapy and antibiotic prophylaxis after septal-occluding device deployment in transcatheter...
Background Current guidelines recommend at least 6 months of antithrombotic therapy and antibiotic prophylaxis after septal-occluding device deployment in transcatheter closure of atrial septal defect. It has been estimated that it takes ≈6 months for complete neo-endothelialization; however, neo-endothelialization has not previously been assessed in vivo in humans. Methods and Results The neointimal coverage of septal occluder devices was evaluated 6 months after implantation in 15 patients by angioscopy from the right atrium. Each occluder surface was divided into 9 areas; the levels of endothelialization in each area were semiquantitatively assessed by 4-point grades. Device neo-endothelialization was sufficient in two thirds of patients, but insufficient in one third. In the comparison between patients with sufficiently endothelialized devices of average grade score ≥2 (good endothelialization group, n=10) and those with poorly endothelialized devices of average grade score <2 (poor endothelialization group, n=5), those in the poor endothelialization group had larger devices deployed (27.0 mm [25.0-31.5 mm] versus 17.0 mm [15.6-22.5 mm], respectively) and progressive right heart dilatation. The endothelialization was poorer around the central areas. Moreover, the prevalence of thrombus formation on the devices was higher in the poorly endothelialized areas than in the sufficiently endothelialized areas (Grade 0, 94.1%; Grade 1, 63.2%; Grade 2, 0%; Grade 3, 1.6%). Conclusions Neo-endothelialization on the closure devices varied 6 months after implantation. Notably, poor endothelialization and thrombus attachment were observed around the central areas and on the larger devices.
Topics: Angioscopy; Heart Septal Defects, Atrial; Humans
PubMed: 34533044
DOI: 10.1161/JAHA.120.019282 -
Journal of Cardiology May 2021Detection of the early stage of atherosclerosis, which does not exhibit macroscopic morphological changes, is currently beyond the scope of any available imaging...
BACKGROUND
Detection of the early stage of atherosclerosis, which does not exhibit macroscopic morphological changes, is currently beyond the scope of any available imaging techniques. Collagens provide mechanical support of vascular wall and subtype I is the major component of the normal vascular wall. During the process of atherosclerosis, collagen III appears first, followed by subtypes IV and V during fibrosis of the intima. Therefore, the presence of collagen III indicates initiation of atherosclerosis. Here, we aimed to visualize collagen subtypes in human coronary wall.
METHODS
Under microscopy, collagen III was stained emerald-green, collagen I was red, and IV and V were pink in the presence of a mixture of Silius red and Fast green dyes. Fifty-one coronary arteries excised from 20 human autopsy subjects were classified by angioscopy and histology as normal segments, white and yellow plaques, and examined after staining collagen subtypes in their superficial layer with the same dye mixtures.
RESULTS
Normal coronary segments with intimal thickness ≦200 μm stained red, with thickness >200 μm stained red and emerald-green in a mosaic pattern or emerald-green alone, yellow plaques without a necrotic core were pink, and those with a necrotic core showed no staining.
CONCLUSION
The results suggested that coronary segments stained red indicate no atherosclerosis, red and emerald-green in a mosaic pattern indicates initiation of atherosclerosis, emerald-green is early-stage atherosclerosis, pink is advanced stage of atherosclerosis, and no staining shows the end stage of atherosclerosis at least in superficial layer of coronary artery. Therefore, dye-staining angioscopy using Silius red and Fast green dyes in combination could be used to detect the early and advanced stage of atherosclerosis in superficial layer of human coronary artery.
Topics: Angioscopy; Collagen; Coronary Artery Disease; Coronary Vessels; Humans; Plaque, Atherosclerotic
PubMed: 33162263
DOI: 10.1016/j.jjcc.2020.09.011 -
Journal of the American College of... May 1983The feasibility of in vivo coronary angioscopy was tested utilizing a 1.8 mm angioscope in vessels where blood had been replaced by optically clear liquids, including a...
The feasibility of in vivo coronary angioscopy was tested utilizing a 1.8 mm angioscope in vessels where blood had been replaced by optically clear liquids, including a new perfluorocarbon emulsion. After trials in postmortem canine and human coronary arteries, in vivo intraluminal visualization was accomplished in the dog with a catheterization technique and in patients during open heart surgery. The results demonstrate the feasibility and potential clinical usefulness of direct visualization of intravascular anatomy and disease, analogous to endoscopy of other organ systems.
Topics: Animals; Coronary Vessels; Dogs; Endoscopy; Fiber Optic Technology; Fluorocarbons; Humans
PubMed: 6833670
DOI: 10.1016/s0735-1097(83)80145-4 -
Journal of the American College of... Jun 1992In a majority of instances, both unstable angina and acute myocardial infarction occur secondary to plaque disruption and thrombus formation. Although the pathogenetic...
In a majority of instances, both unstable angina and acute myocardial infarction occur secondary to plaque disruption and thrombus formation. Although the pathogenetic substrates are similar the clinical presentations are quite different. It is hypothesized in this editorial review that the amount of acute thrombus formation and specifically fibrin deposition is greater in myocardial infarction than in unstable angina. Both angiographic studies and studies analyzing the response to thrombolytic agents suggest more thrombus in myocardial infarction than in unstable angina. These data have recently been substantiated by angioscopic observations in these acute syndromes suggesting that more platelet-rich (whitish) thrombus occurs in unstable angina and more red thrombus in myocardial infarction. The red thrombus presumably would be more responsive to thrombolytic agents. Furthermore, it is proposed that these differences between syndromes in acute thrombus formation can be explained by the interplay of vessel wall injury, coagulation variables or stasis of blood flow occurring at or after the time of presentation. Therefore, acute myocardial infarction is associated with occlusive, fibrin-rich thrombus, whereas in unstable angina, the thrombus is nonocclusive, mural and possibly more platelet-rich. However, the clinical syndrome that ultimately develops after plaque disruption is dependent not only on the amount of acute thrombus formation but on the net result of all factors that influence the balance between coronary blood supply and myocardial oxygen demand.
Topics: Angina, Unstable; Blood Platelets; Coronary Angiography; Coronary Thrombosis; Endoscopy; Fibrin; Fibrin Fibrinogen Degradation Products; Fibrinopeptide A; Humans; Myocardial Infarction; Plasminogen Inactivators; Thrombolytic Therapy
PubMed: 1593062
DOI: 10.1016/0735-1097(92)90632-w -
Annals of the Royal College of Surgeons... Jan 1998The concept of vein quality has been slow to gain widespread acceptance, but an increasing body of evidence suggests that vein quality is relevant to the success of... (Clinical Trial)
Clinical Trial Randomized Controlled Trial Review
The concept of vein quality has been slow to gain widespread acceptance, but an increasing body of evidence suggests that vein quality is relevant to the success of bypass grafting for peripheral vascular disease. The angioscope represents an additional tool for monitoring and preparing vein grafts during infrainguinal revascularisation. Within the overall theme of vein quality, this paper presents the cumulative experience with vascular endoscopy at Bristol Royal Infirmary. In clinical studies, the diagnostic role of angioscopy in quality control was evaluated by grafting preexisting, angioscopically detected, intraluminal abnormalities and correlating them with histological appearances. There were significant associations between angioscopy/histology grades and graft patency. To enable quantification of images, an innovative computerised video image processing method has been developed and validated against simultaneous ultrasound measurements of segments of saphenous vein. The therapeutic applications of angioscopy in vein graft preparation were studied prospectively in patients undergoing in situ femoropopliteal/distal bypasses by randomisation to full angioscopic or conventional preparation. There was a significant reduction in wound morbidity. Completion angioscopy and arteriography were complementary in the detection of technical defects. Harvested vein was maintained in organ culture to assess further the influence of pre-existing pathology and the potentially traumatic effects of angioscopy on development of neointimal hyperplasia. There was a significant correlation between the extent of pre-existing abnormality and smooth muscle cell proliferative activity in culture and although angioscopy caused endothelial cell loss, this did not stimulate neointimal hyperplasia in vitro. This work confirms that vein quality can be evaluated prospectively by angioscopy and that substandard vein is associated with inferior patency rates. Angioscopic and histological evaluation, together with vein organ culture studies, have definite application in helping to elucidate the mechanisms underlying graft failure.
Topics: Adult; Aged; Aged, 80 and over; Angioscopy; Blood Vessel Prosthesis Implantation; Endothelium, Vascular; Female; Graft Occlusion, Vascular; Humans; Hyperplasia; Male; Middle Aged; Organ Culture Techniques; Peripheral Vascular Diseases; Prospective Studies; Saphenous Vein
PubMed: 9579121
DOI: No ID Found -
Journal of Biomedical Optics Sep 2023The scanning fiber endoscope (SFE), an ultrasmall optical imaging device with a large field-of-view (FOV) for having a clear forward view into the interior of blood...
SIGNIFICANCE
The scanning fiber endoscope (SFE), an ultrasmall optical imaging device with a large field-of-view (FOV) for having a clear forward view into the interior of blood vessels, has great potential in the cardiovascular disease diagnosis and surgery assistance, which is one of the key applications for short-wave infrared biomedical imaging. The state-of-the-art SFE system uses a miniaturized refractive spherical lens doublet for beam projection. A metalens is a promising alternative that can be made much thinner and has fewer off-axis aberrations than its refractive counterpart.
AIM
We demonstrate a transmissive metalens working at 1310 nm for a forward viewing endoscope to achieve a shorter device length and better resolution at large field angles.
APPROACH
We optimize the metalens of the SFE system using Zemax, fabricate it using e-beam lithography, characterize its optical performances, and compare them with the simulations.
RESULTS
The SFE system has a resolution of at the center of field (imaging distance 15 mm), an FOV of , and a depth-of-focus of , which are comparable with a state-of-the-art refractive lens SFE. The use of the metalens reduces the length of the optical track from 1.2 to 0.86 mm. The resolution of our metalens-based SFE drops by less than a factor of 2 at the edge of the FOV, whereas the refractive lens counterpart has a times resolution degradation.
CONCLUSIONS
These results show the promise of integrating a metalens into an endoscope for device minimization and optical performance improvement.
Topics: Endoscopy, Gastrointestinal; Radionuclide Imaging; Refraction, Ocular; Lens, Crystalline; Lenses
PubMed: 36911164
DOI: 10.1117/1.JBO.28.9.094802 -
Journal of Cardiology Jan 2023Chronic total occlusion (CTO) is a high-risk factor for stent thrombosis, but little is known about the difference in neointimal healing between CTO and non-CTO lesions...
BACKGROUND
Chronic total occlusion (CTO) is a high-risk factor for stent thrombosis, but little is known about the difference in neointimal healing between CTO and non-CTO lesions regarding implanted stents. We investigated factors affecting neointimal healing after stent implantation for CTO and non-CTO lesions using angioscopy.
METHODS
We retrospectively evaluated 106 stents in 85 consecutive patients between March 2016 and July 2020. Their average age was 68 ± 11 years, and participants (73 male and 12 female) underwent follow-up angiography and angioscopy 1 year after percutaneous coronary intervention (PCI). The stents (n = 106) were divided into three groups according to the lesion status at the previous PCI: CTO (n = 17), acute coronary syndrome (ACS) (n = 35), and stable coronary artery disease without CTO or non-CTO (n = 54).
RESULTS
The neointimal stent coverage grade was significantly lower in the CTO and ACS groups than in the non-CTO group (0.4 ± 0.5, 0.9 ± 0.8, and 1.4 ± 0.8, respectively, p < 0.001). Thrombi were significantly more frequent in CTO and ACS than in non-CTO (71 %, 51 %, and 15 %, respectively, p < 0.001). The yellow grade in CTO was comparable to that in ACS but significantly higher in CTO than in non-CTO (CTO vs. ACS vs. non-CTO 1.5 ± 0.7, 1.4 ± 0.6, and 0.9 ± 0.7, respectively, p = 0.007).
CONCLUSIONS
Delayed healing occurs in stents implanted for CTO lesions. Longer dual-antithrombotic therapy may be beneficial.
Topics: Humans; Male; Female; Middle Aged; Aged; Percutaneous Coronary Intervention; Angioscopy; Coronary Thrombosis; Retrospective Studies; Coronary Angiography; Neointima; Treatment Outcome; Coronary Occlusion; Chronic Disease
PubMed: 36057486
DOI: 10.1016/j.jjcc.2022.08.008 -
Circulation Journal : Official Journal... 2016Drug-eluting stents (DES) have reduced late loss and target lesion revascularization through the inhibition of neointimal hyperplasia, but instead increased the risk of... (Comparative Study)
Comparative Study
BACKGROUND
Drug-eluting stents (DES) have reduced late loss and target lesion revascularization through the inhibition of neointimal hyperplasia, but instead increased the risk of very late stent failure due to incomplete neointimal coverage and neoatherosclerosis. Although newer DES are more effective and safer than the first-generation DES, the difference in the condition of the stented lesions between Resolute zotarolimus-eluting stents (R-ZES) and Endeavor zotarolimus-eluting stents (E-ZES) on angioscopy has not been reported.
METHODS AND RESULTS
Consecutive patients who received R-ZES (n=46) or E-ZES (n=46) for de novo lesion of native coronary artery and had 1-year follow-up angioscopy were examined. Yellow color (grade 0-3), neointimal coverage (grade 0-2), heterogeneity score (maximum-minimum neointimal coverage grade) and thrombus (presence or absence) at stented lesion were evaluated. The maximum yellow color grade (1.2±0.9 vs. 0.7±1.0, P=0.005) was higher in R-ZES than in E-ZES. The maximum (1.9±0.3 vs. 1.5±0.5, P<0.001) and minimum (1.1±0.7 vs. 0.4±0.5, P<0.001) coverage grade was higher in E-ZES than in R-ZES. The heterogeneity score was higher in R-ZES than in E-ZES (1.0±0.5 vs. 0.7±0.7, P=0.007). Prevalence of thrombus was not different between the 2 stents (6.5% vs. 2.2%, P=0.4).
CONCLUSIONS
E-ZES had better neointimal coverage with less yellow plaque and lower heterogeneity score than R-ZES. The lesions with E-ZES appeared more stable than those with R-ZES. (Circ J 2016; 80: 650-656).
Topics: Aged; Angioscopy; Atherosclerosis; Drug-Eluting Stents; Female; Follow-Up Studies; Humans; Male; Middle Aged; Neointima; Plaque, Atherosclerotic; Sirolimus
PubMed: 26794153
DOI: 10.1253/circj.CJ-15-1119