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PubMedDate not supplied

Selective percutaneous "biopsy" of atheromatous plaque tissue for cell culture.

The combination of percutaneous atherectomy and angioscopy enabled a selective "biopsy" of protruding atheromatous plaque material from 11 patients with arterial occlusive disease. The removed specimens were cultivated as adhering explants or single cells were obtained by enzymatic disintegration. The vast majority of the cultivated cells resembled fibroblasts, but could be identified as smooth muscle cells by their smooth muscle alpha-actin content. Proliferation rate was slow with 0.1 doublings per day. Endothelial cells were not observed by immunologic criteria. The described biopsy technique and in vitro evaluation of cultured human atheromatous plaque material may be useful for a better understanding of atherogenesis.

Actins↗
PubMed1993

Endovascular obliteration of in situ saphenous vein arteriovenous fistulas during tibial bypass.

Current methods of ligating venous branches during in situ vein tibial bypass are associated with significant wound complications, especially in diabetics. Making only proximal and distal wound incisions could avoid these wound problems. We report the use of endovascular techniques with coils and balloons guided by intraoperative arteriography and angioscopy to obliterate arteriovenous (AV) fistulas in three elderly diabetic patients undergoing tibial bypass. In all cases the proximal and distal vessels were first isolated and deemed suitable for bypass. The greater saphenous vein was prepared for the proximal and distal anastomosis, and angioscopically guided valvulotomy was performed. An introducer sheath was placed through a large proximal saphenous side branch for vascular access. With the use of fluoroscopy, AV fistulas were serially identified and cannulated with a guidewire. A guide catheter, passed over the wire into the side branch, served as the conduit through which coils and balloons were placed. Proximal and distal anastomoses were completed and arteriography performed. We were successful in obliterating AV fistulas in all three patients, but completion arteriography revealed additional AV fistulas requiring surgical ligation in two patients. Furthermore, operative time was increased by 1 1/2 to 5 hours. Two of three patients had wound infections, one at the proximal and one at the distal incision. All patients were discharged with a functioning bypass and no AV fistulas were seen on duplex scans. Endovascular obliteration of AV fistulas is feasible but is currently limited by prolonged operative time and incomplete obliteration.

Aged↗
PubMed1998

Chronic pulmonary thromboendarterectomy complicated by antithrombin III deficiency and antiphospholipid syndrome.

Pulmonary thromboendarterectomy was performed on two patients with chronic pulmonary thromboembolism showing thrombotic tendency. Patient 1 was a 25-year-old male with the disease complicated by congenital antithrombin III deficiency. Patient 2 was a 21-year-old male with the disease complicated by antiphospholipid syndrome. Both patients were admitted to the center upon showing dyspnea. Lung perfusion scintigraphy revealed multiple defects in the right and left lungs. Pulmonary arteriography showed occlusion and stenosis from lobar to segmental arteries. Cardiac catheterization showed marked pulmonary hypertension. Pulmonary angioscopy confirmed the presence of organized thrombi while an intravascular ultrasound revealed a thickening of the pulmonary arterial walls in both lungs. After the insertion of an inferior vena cava filter in each patient, surgery was performed. Following a median sternotomy, a cardiopulmonary bypass was utilized to induce deep hypothermia at a pharyngeal temperature of 16 degrees C, after which a thromboendarterectomy of the bilateral pulmonary arteries was performed under intermittent circulatory arrest. A large amount of organized thrombi was extracted from these arteries. After surgery, both patients showed good postoperative outcome with improved blood flow in both lungs, reduced pulmonary arterial pressure and increased cardiac output.

Adult↗
PubMed2000

The role of polyester patch angioplasty in carotid endarterectomy: a multicenter study.

The objectives of this study were to examine the morphology, restenosis, dilatation, and possible complications of polyester collagen impregnated carotid patches. Between March 1994 and January 1995, 207 patients (56 females and 151 males) undergoing 221 carotid endarterectomies (CE) with a collagen-impregnated knitted polyester patch were enrolled in a European prospective multicenter study. Patches were used for arteries deemed to be smaller than usual by visual inspection. General anesthesia was used in 201 procedures (91%), and a shunt was used in 76 procedures (34.4%). One hundred fourteen CE (51.6%) were checked by a perioperative arteriography or angioscopy. The diameter of the internal carotid artery (ICA) and carotid bulb (CB) were measured by duplex scan both preoperatively and every 6 months during follow-up. The main end point was carotid occlusion or restenosis, defined as a stenosis of 50% or more according to NASCET criteria. Carotid polyester-impregnated patches appear to be reliable. The patch was easy to cut and suture, and hemostasis was obtained immediately. No rupture occurred. However, the higher restenosis rate in women may restrict the use of polyester patch to men.

Adult↗
PubMed2001

New developments in the detection of vulnerable plaque.

Failure of coronary angiography (luminography) in prediction of future acute coronary syndromes has cast a shadow of doubt over the value of this old gold-standard technique. The fact that angiographically invisible or nonsignificant lesions cause the majority of acute coronary syndromes has driven scientists to develop new diagnostic methods. In this article, we review the ongoing worldwide research on both invasive techniques (such as intravascular angioscopy and colorimetry, ultrasound, thermography, optical coherence tomography, near infrared spectroscopy, Raman spectroscopy, fluorescence emission spectroscopy, elastography, magnetic resonance imaging and spectroscopy, nuclear immunoscintigraphy, electrical impedance imaging, vascular tissue doppler, and shear stress imaging) and noninvasive techniques (such as MRI, contrast-enhanced MRI with and without immunolabeled agents, electron beam computed tomography, multi-slice spiral / helical computed tomography, and nuclear imaging, including positron emission tomography). Each of these techniques and their potential combination holds promise for characterization of plaques responsible for acute coronary syndromes, namely vulnerable plaque.

Contrast Media↗
PubMed1992

Intravascular ultrasound in coronary atherosclerosis: a new approach to clinical assessment.

Intravascular ultrasound evaluation of the coronary arteries by means of a selective coronary catheter attached to an ultrasound unit has afforded precise depiction of coronary lumen diameter and area at the level of the catheter tip. The arterial wall at this level can be evaluated for lipid, fibrous tissue, calcification, wall dissections, and intraluminal thrombi. The technique has the advantage over coronary angioscopy and angiography in that it does not require infusions or injections to allow visualization, and it has the ability to depict the inside of the arterial wall. The current disadvantages include the inability to visualize the vessel segments distal to the catheter tip. Three-dimensional reconstruction techniques allow depiction of the segment of the artery traversed by the catheter tip. The use of Doppler ultrasound imaging provides information on coronary flow velocities through coronary obstructions. Intravascular ultrasound images may provide information that complements the coronary arteriogram and may have an impact on patient care and clinical investigation strategies.

Animals↗
PubMed1994

Histopathologic correlates of unstable ischemic syndromes in patients undergoing directional coronary atherectomy: in vivo evidence of thrombosis, ulceration, and inflammation.

Complex coronary morphologic abnormalities with thrombus and ulceration have been recognized in acute ischemic syndromes by angiography, angioscopy, and autopsy. However, in vivo histopathologic correlates of unstable ischemic syndromes have not been described. The purpose of this study was to characterize intracoronary lesion morphologic abnormalities by analyzing specimens excised by directional atherectomy in patients with different ischemic syndromes. Tissue specimens removed by directional coronary atherectomy of primary lesions in native vessels were matched blindly to the clinical status of 130 patients representing 43% of a consecutive directional coronary atherectomy population of 300 patients; 824 specimens (range per patient 1 to 30, mean 6.3) were obtained. Clinical subgroups were prospectively classified as recent myocardial infarction (< or = 15 days, mean 6, range 1 to 15 days), 48 patients; prolonged rest angina, 34 patients; crescendo angina, 29 patients; and stable angina, 19 patients. Shavings were prospectively analyzed for presence of thrombus, ulceration, or chronic inflammatory cells. Thrombus was observed in 33 (69%) patients with recent myocardial infarction, 17 (50%) with rest angina, 12 (41%) with crescendo angina, 7 (37%) with stable angina (p = 0.048). Plaque ulceration was identified in 12 (25%) patients with recent myocardial infarction, 4 (12%) with rest angina, 2 (7%) with crescendo angina, and 1 (5%) with stable angina (p = 0.09). Inflammatory cells were noted in the specimens of 32 (67%) patients with recent myocardial infarction, 16 (45%) with rest angina, 12 (41%) with crescendo angina, and 9 (45%) with stable angina.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗
PubMed1995

Identification of intervention patients at increased risk.

Many patients who once would have been classified as being at high risk are now deemed candidates for interventional cardiologic procedures. Definitions of risk thereby warrant reconsideration. Although the angiographic characteristics of lesions clearly identify patients at increased risk of adverse outcomes after angioplasty, important components such as thrombus may go unrecognized. Angioscopy provides a more precise means of identifying thrombus, but its use is not feasible in all patients scheduled for angioplasty. A triage system developed on the basis of clinical criteria is therefore desirable. Prospective data have suggested that the degree of risk is high in patients with unstable angina (particularly when refractory to medical therapy) and those who have recently undergone successful thrombolytic therapy for myocardial infarction. After stent implantation, patients who receive full anticoagulation therapy are at high risk of bleeding and subacute thrombosis, which may lead to myocardial infarction. New preventive strategies are required to optimize outcomes in patients with clinical characteristics indicative of high risk.

Angina, Unstable↗
PubMed1995

Cardiac allograft vasculopathy: current concepts.

The major cause of late death in cardiac transplant recipients is cardiac allograft vasculopathy, also referred to as cardiac transplant atherosclerosis, which occurs in 15% to 20% of transplant recipients. It differs from traditional atherosclerosis in that it is a concentric and diffuse intimal hyperplastic process; the internal elastic lamina remains intact; calcification is rare; and the disease tends to develop rapidly. Although no definitive reason for cardiac allograft vasculopathy has been established, it has been suggested that it may be caused by a combination of immunologic and nonimmunologic damage to endothelial cells that results in myointimal proliferation. Intravascular ultrasound and coronary angioscopy are more sensitive diagnostic measures of cardiac allograft vasculopathy than coronary angiography. Although retransplantation currently seems to be the only definitive therapy for cardiac allograft vasculopathy, it has shown only fair results.

Coronary Artery Disease↗
PubMed1976

Optic disk neovascularization associated with chronic uveitis.

Disk neovascularization associated with chronic uvetitis occurred in five patients. The uveitis was most frequently diagnosed as chronic cyclitis, with a marked inflammatory cell response in the vitreous body. Using direct and indirect ophthalmoscopy, slit-lamp biomicroscopy with the Goldmann contact lens, perimetry, and fluorescein angiography and angioscopy, we found no areas of vascular occlusion or nonperfusion. Inflammation probably produced chemical mediators capable of traveling to the optic disk and inducing neovascular proliferation, in the absence of retinal vascular occlusion.

Adolescent↗
PubMed1983

Vascular leakage, neovascularization, and vitreous hemorrhage in senile bullous retinoschisis.

Retinal detachment is the primary complication of bullous retinoschisis, a benign abnormality of the peripheral retina. We examined three patients (all women, 43, 55, and 56 years old) with typical bullous retinoschisis who had vitreous hemorrhage. In each case, there were sclerotic retinal vessels over the surface of the schisis cavity along with neovascularization above the central portion of the cyst. In one case there was also neovascularization of the peripheral retina in an area distant from the schisis. These findings were confirmed by fluorescein angiography in one case; the other two cases demonstrated similar changes by fluorescein angioscopy. Fluorescein angiography, also demonstrated intraretinal dye leakage from vessels along the posterior extent of the schisis, as well as from an adjacent area of white without pressure.

Female↗
PubMed1989

Experimental and clinical applications of angioscopic guidance for laser angioplasty.

The role of angioscopic monitoring and aiming for control of laser intervention in the vascular system was initially investigated in 48 vessels in 33 dogs, and the techniques were then applied to 30 patients undergoing intraoperative or percutaneous laser-probe angioplasty treatment for long atherosclerotic occlusions of the femoral and popliteal arteries or well-localized lesions of the superficial femoral artery. Experimental bare argon fiber laser application in 20 normal canine arteries in vivo demonstrated that small-diameter laser fibers could be accurately aimed by manipulations of the scope. However, advancement of the fiber resulted universally in perforation, with extravasation and thermal damage of surrounding tissues after 2 seconds of argon laser energy at low power. In 28 canine and 2 human veins, angioscopically guided metallic-tipped laserprobes were used to divide 82 valve cusps in preparation for in-situ bypass, with satisfactory aiming and monitoring achieved expeditiously by manipulations of the angioscope. We conclude that angioscopic aiming of lasers is feasible in normal vessels or localized lesions. In contrast, angioscopy has a restricted role for guidance of laser angioplasty in atherosclerotic, occluded arteries, and does not prevent perforation. Postprocedural inspection allows immediate detection of complications and may avert or predict poor outcome.

Angioplasty, Balloon↗
PubMed1991

Excimer laser angioplasty during aortocoronary bypass grafting.

Laser coronary angioplasty using the 308-nm Excimer laser was successfully performed intraoperatively during coronary artery bypass grafting. It achieved a reduction of the left anterior descending artery stenosis from 99% to 25% as seen on angioscopy, without evidence of vascular perforation or intimal disruption. The Excimer laser offers the opportunity for intraoperative endovascular remodeling and recanalization and has a potential role as an adjunct to existing standard coronary artery bypass grafting protocol.

Angioplasty, Laser↗
PubMed1995

Coronary artery aneurysms after angioplasty and atherectomy.

Coronary artery aneurysm formation after percutaneous transluminal coronary angioplasty and directional coronary atherectomy is unusual. We report the case of a left anterior descending coronary artery aneurysm that formed in such a patient. The left anterior descending coronary artery was bypassed and the aneurysm was plicated with the aid of coronary angioscopy. The English-language medical literature on the topic of coronary artery aneurysms is reviewed.

Angioplasty, Balloon, Coronary↗
PubMed1991

Spiral laminar flow in arteries?

Spiral blood-flow patterns in infrainguinal blood-vessels were observed at angioscopy in 54 patients who underwent peripheral vascular reconstruction; the endoluminal surface had spiral folds in 51 of 75 arteries examined. Spiral flow patterns, congruous with inherent endoluminal anatomical features, might more accurately represent blood-flow in infrainguinal arteries than current models of laminar flow.

Arteries↗
PubMed1984

The persistent enigma of percutaneous angioplasty.

In summary, while both the short-term and long-term success of PTCA is undeniable in most patients, the basis for this success remains an enigma. Admittedly, simply because "plaque fractures" and "dissection clefts" have been observed to occur as the result of artifact, one cannot exclude the possibility that the success of PTCA may be related to these lesions. Alternatively, the fact that improved vessel patency is frequently observed angiographically and pathologically in the absence of such lesions precludes firm assurance that such lesions are the basis for a successful dilatation. Identification of the mechanism responsible for the success of PTCA is more than a matter of simple curiosity: improved understanding of the basis for successful PTCA might lead to technical refinements in the procedure and allow one to better tailor the technique to individual variations in lesion morphology. Perhaps the combined use of selective, intra-vascular angioscopy at the time of PTCA will enhance our understanding of the fundamental mechanism responsible for this highly effective therapy.

Angioplasty, Balloon↗
PubMed1989

New percutaneous transluminal coronary angioscope.

A new percutaneous transluminal coronary angioscopic catheter has been developed for visualization of the coronary artery. A specially made balloon, fixed at the catheter tip, and an angulation mechanism made a precise coaxial alignment possible in the coronary lumen. This angioscopic catheter, 1.22 mm in outer diameter, has four channels, one for irrigation in which a 0.36 mm (0.014 in.) angioplasty guide wire can be used. With the use of this angioscope, coronary lumens in 8 dogs, thrombi that were produced with copper coils in the left anterior descending coronary artery in 11 dogs, atherosclerotic coronary arteries in 20 patients during cardiac catheterization and the sequence of transluminal coronary angioplasty in 1 patient were observed. The angioscopic catheter was introduced into the coronary artery by an 8F guide catheter. The steerable guide wire enabled the angioscopic catheter to be accurately and safely inserted into the target lesion in all cases. The inflated balloon and angulation mechanism allowed a curved coronary lumen and atheroma to be seen with a limited volume of irrigation fluid. Visualization was good (complete visualization of the inner lumen) in 46% (10 of 22 lesions), moderate (visualization of greater than 50% of the inner lumen) in 36% (8 of 22 lesions) and poor (visualization of less than 50% of the inner lumen) in 18% (4 of 22 lesions) in humans. There were no major complications. These preliminary experiences in closed chest cardiac catheterization in dogs and in humans indicate the feasibility of this angioscope. The information yielded by angioscopy may be clinically useful in the study of the pathophysiologic changes in coronary disease that are not detected by coronary arteriography.

Aged↗
PubMed1991

Quantitative coronary arteriographic methods in the interventional catheterization laboratory: an update and perspective.

Recent research advances in the area of quantitative coronary arteriography are described with respect to their potential role in assessing the effects of interventional therapy and monitoring the restenosis process. Specific areas emphasized are the importance of quantitative arteriography and absolute measures of arterial dimension in monitoring restenosis, the development of a computerized method for measuring lesion roughness, the potential role of measuring stenosis flow reserve based on component analysis principles, limitations of direct measures of myocardial flow reserve using a digital angiographic method and cautionary notes about clinical applications of videodensitometry. The current use of radiography and quantitative measures in limiting arterial injury are briefly reviewed. Finally, a perspective is put forth on the need to develop complementary roles for endovascular echocardiography and angioscopy with existing radiographic imaging technology.

Angiography, Digital Subtraction↗