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At least 181 records · Page 10Linked to original sources
PubMed1993

Coronary artery rupture and pseudoaneurysm formation resulting from percutaneous coronary angioscopy.

We describe a case in which coronary angioscopy was complicated by inability to deflate the device's occlusion balloon. Rapid over-inflation to rupture the balloon resulted in massive dissection of the artery, pseudoaneurysm formation, and ultimately coronary bypass. While the cause of failure of balloon deflation remains obscure, deliberate over-inflation to cause rupture may be hazardous.

Adult↗
PubMed1993

Comparative evaluation of laser Doppler flux metering, bulbar conjunctival angioscopy, and nail fold capillaroscopy in sickle cell disease.

Eleven adult patients with stable sickle cell disease (SCD) were investigated twice at a 15-day interval by nail fold capillaroscopy (NFC), bulbar conjunctival angioscopy (BCA), and laser Doppler flux metering (LDF). NFC and BCA are essentially descriptive. NFC revealed, in some patients, network patterns similar to those observed in vasculitis. BCA provides a reproducible method for the visual assessment of the microcirculation. When using a rating scale with five criteria it identified abnormalities related to both altered red blood cells and vascular morphology but failed to discriminate between patients. LDF, in contrast, is quantifiable and showed reproducible characteristic reactive alterations of vasomotion in response to ischemia after 3 min of occlusion. The SCD patients had a delayed response, best measured by the recovery half time, which was four to five times longer than that of normal subjects. In addition, the cold provocative test was always abnormal, as evidenced by a significant drop in the contralateral flux, and was often poorly tolerated. The observed trends suggest that BCA and LDF should be performed in a large cohort of patients, both in the steady state and during vasoocclusive crises. These methods seem to be useful complementary noninvasive procedures to cellular and clinical evaluation monitoring for therapeutic trials.

Adult↗
PubMed1994

Back-table renal allograft angioscopy and thrombolysis.

Poor back-table perfusion of a renal allograft may occur as a result of intravascular thrombosis of the renal artery branches. We herein report such a case where back-table angioscopy was performed to confirm the diagnosis, followed by successful thrombolysis using urokinase under hypothermic conditions.

Adenosine↗
PubMedDate not supplied

Multislice CT virtual angioscopy of the abdomen.

BACKGROUND: Computed tomographic (CT) angiography represents an important clinical tool in the evaluation of vascular disorders. Virtual angioscopy can be reconstructed with volumetric CT data sets. We evaluated the feasibility and clinical value of this application in the assessment of abdominal vessels. METHODS: Data sets of CT angiographic studies obtained with helical (n = 120) and multislice (n = 180) CT scanners were analyzed on a workstation for postprocessing. Vascular evaluation was done on conventional enhanced axial images, three-dimensional reconstructions, and virtual angioscopic images. RESULTS: We made 123 studies in patients without aortic disease. Of the patients evaluated for stent-graft treatment, 63 showed normal patency, seven had partial thrombosis of the stent-graft, five showed total occlusion of the stent-graft, and 10 had leaks. From the 92 remaining CT studies, 63 vascular aneurysms and nine dissections were diagnosed. CONCLUSION: The current technology produces high-quality virtual angioscopic images. Although axial and multiplanar views are usually adequate for detecting a vascular disorder, virtual angioscopic views better define anatomic details.

Abdomen↗
PubMed1999

Pseudoaneurysm of the abdominal aorta: evaluation with virtual angioscopy of spiral-CT data sets.

We describe a case of graft-related pseudoaneurysm of the abdominal aorta evaluated with spiral CT and DSA. Spiral CT data sets were processed to obtain surface-rendered internal views (virtual angioscopy, VA) of the graft and the pseudoaneurysm, and to demonstrate from inside the lumen the site of dehiscence. A jet flow phenomenon inside the pseudoaneurysm was observed at DSA. Spiral-CT axial images, multiplanar volume reconstructions with maximum intensity projections, and shaded surface display showed the site of rupture. The VA findings were: (a) from inside the graft lumen, the evidence of a communication canal between the graft and the pseudoaneurysm; and (b) from inside the pseudoaneurysm, the presence of a jet flow. The VA findings showed good correlation with those obtained with the other imaging techniques.

Aneurysm, False↗
PubMed2006

MDCT and virtual angioscopy in spontaneous aortocaval fistula.

Aortocaval fistula is a rare, less than 1%, but life threatening complication, of abdominal aortic aneurysm. Mortality is high but prompt recognition of the fistula can reduce mortality rate. The multidetector row CT (MDCT) findings in a 69-year-old patient with a complex medical history characterized by previous episodes of myocardial ischemia, is reported. MDCT shows an early homogeneous enhancement of the inferior vena cava, slightly dilated at the liver level and markedly narrowed above the renal vein due to aneurysm compression. The patient underwent to emergency laparotomy but died during surgery for cardiac arrest. MDCT allows a prompt recognition of the fistula and different computerized reconstruction techniques as maximum intensity projection (MIP), multiplanar reformatting (MPR) and virtual angioscopy (VA) added imaging information for surgery.

Aged↗
PubMed1997

Angioscopy variables predictive of early angiographic outcome after excimer laser-assisted coronary angioplasty.

This study attempted to determine whether anatomic findings at angioscopy were associated with adverse early angiographic outcomes following excimer laser-assisted coronary angioplasty. Predictive factors of either coronary abrupt vessel closure or early (< or =24 hours) restenosis after percutaneous coronary angioplasty, including clinical and angiographic variables, have been widely evaluated. The role of angioscopic findings may contribute to identification of patients at risk for early poor outcome. Thirty-seven patients with severe lesions, including 23 total occlusions which underwent successful percutaneous transluminal coronary angioplasty (PTCA) with laser irradiation and adjunctive balloon dilatation (n = 35), or stand alone laser (n = 2), had concomitant angioscopic imaging of the target vessel. All patients had a 24-hour angiographic follow up. Early unfavorable outcome (n = 15) was defined as abrupt vessel closure or restenosis (> or = 50% stenosis) at 24 hours. By multivariate logistic regression analysis, immediate post-PTCA residual percent stenosis was associated with a poor outcome (restenosis: 33 +/- 22% vs no restenosis: 21 +/- 14%, p = 0.05). Angioscopic red thrombus aspect was the most significant correlate for early closure or restenosis (7 of 15 patients with unfavorable outcome vs 2 of 22 patients with favorable outcome, odds ratio, 22.9; p < 0.01) and was associated with a significantly higher early minimal lumen diameter loss (1 +/- 0.8 mm in the presence of a red thrombus vs 0.3 +/- 0.5 mm without thrombus, p < 0.005). Red thrombus appearance is associated with an unfavorable early angiographic outcome in patients who undergo laser-assisted coronary angioplasty.

Aged↗
PubMed1998

Angioscopy of culprit coronary lesions in unstable angina pectoris and correlation of clinical presentation with plaque morphology.

This study demonstrates that plaque disruption and thrombus are absent in a considerable number of patients with unstable angina and that culprit lesion morphologies as assessed by angioscopy may differ among the various clinical subsets of patients. Although plaque disruption and thrombus undoubtedly play an important role in the pathogenesis of unstable angina, alternative mechanisms may be responsible for ischemia in some patients.

Adult↗
PubMed1995

Prospective study of the value of prebypass saphenous vein angioscopy.

BACKGROUND: The patency of a saphenous vein graft is directly related to the quality of the vein harvested. Thus, appropriate evaluation of the vein before implanting it as a bypass graft may help identify those veins at high risk for early failure. Accordingly, we prospectively investigated whether prebypass angioscopic assessment of the saphenous vein could identify those vein grafts at particularly high risk of early failure. PATIENTS AND METHODS: Thirty-two greater saphenous veins with a grossly normal appearance were evaluated angioscopically before their use as a bypass conduit. After modification of abnormal segments, all of the veins irrigated well and were used as bypass grafts. RESULTS: Twenty-four patients were available for follow-up at 12 months. Seventeen (71%) had been prospectively classified as having angioscopically normal saphenous veins, while 7 were identified as having abnormal veins. The two groups did not differ significantly in demographics, cardiovascular risk factors, or indications for operative intervention. Twelve of the 17 (70%) normal veins were patent at 1 year; however, only 1 (14%) of the angioscopically abnormal vein grafts remained patent for 12 months (chi-square = 4.27; P = 0.039). CONCLUSION: Angioscopic inspection of the saphenous vein, before insertion as a graft, allows for identification of unrecognized venous disease that portends early graft thrombosis. Exclusion of abnormal veins, based on an abnormal angioscopic appearance, may lead to improved results for lower-extremity revascularization procedures; this supports the value of vein-graft angioscopy.

Angioscopy↗
PubMed1999

Characterization of the unstable lesion by angiography, angioscopy, and intravascular ultrasound.

Acute coronary syndromes are a spectrum of clinical presentations with various pathophysiologic substrates. As such, there is not one single type of lesion responsible for stable or unstable angina, acute myocardial infarction, and sudden cardiac death. Most of the information regarding the characteristics of culprit lesions derives from histopathologic studies, whether postmortem or from atherectomy samples, and from studies using angiography, angioscopy, and intravascular ultrasound. Characterization of the unstable coronary lesion is key to understanding the pathophysiology of coronary artery disease, this knowledge will allow clinicians to individualize treatment according to specific lesion types, and more importantly, will lead to strategies to identify atherosclerotic lesions in their early stages and implement preventive therapies.

Angioscopy↗
PubMed2003

Changes in coronary plaque color and morphology by lipid-lowering therapy with atorvastatin: serial evaluation by coronary angioscopy.

OBJECTIVES: Changes in coronary plaque color and morphology by statin therapy were evaluated using coronary angioscopy. BACKGROUND: Coronary plaque stabilization by statin therapy has not been clarified in humans. METHODS: Thirty-one patients with coronary artery disease were divided into either the comparison group (n = 16) or the atorvastatin group (n = 15). Before treatment and 12 months after, the color and complexity of 145 coronary plaques were determined according to angioscopic findings. The yellow score of the plaque was defined as 0 (white), 1 (light yellow), 2 (yellow), or 3 (dark yellow), and its disrupted score was defined as 0 (smooth surface) or 1 (irregular surface) and as 0 (without thrombus) or 1 (with thrombus). In each patient, the mean yellow score and mean disrupted score were calculated. RESULTS: Mean low-density lipoprotein cholesterol (LDL-C) decreased by 45% in the atorvastatin group, whereas an increase of 9% was seen in the comparison group. The mean yellow score decreased from 2.03 to 1.13 in the atorvastatin group, whereas it increased from 1.67 to 1.99 in the comparison group. There was a good correlation between the change in the mean yellow score and the change in LDL-C levels (r = 0.81, p < 0.0001). The change in the mean yellow score and mean disrupted score differed significantly between the two groups (p = 0.002 and p = 0.03, respectively). CONCLUSIONS: This is the first report clarifying detailed changes in coronary plaque by statin in humans. This study indicated that lipid-lowering therapy changes plaque color and morphology and should then lead to coronary plaque stabilization.

Aged↗
PubMed1995

Infrainguinal arterial reconstruction with non-reversed autologous vein after angioscopy guided valvulotomy ex situ.

AIMS: The advantages of in situ autologous vein grafts for long infrainguinal arterial reconstructions are the tapered conduit, minimising size mismatch at proximal and distal anastomoses, and the possibility of using small sized veins with good results. Unfortunately, in about 30% of legs the ipsilateral saphenous vein is inadequate rendering in situ bypass grafting impossible. To profit from a valveless autologous vein graft in these cases we routinely performed ex situ valvulotomy after harvesting the contralateral saphenous vein or good quality segments of the ipsilateral saphenous vein. METHODS: The ex situ valvulotomy was performed under angioscopic guidance using a flushing-type Mill's valvulotome. RESULTS: Fifty non reversed grafts in 46 patients entered a prospective surveillance program. Primary and primary-assisted patency rates at 2 years were 68% and 82% respectively, early graft thrombosis 2%, late stenosis 8% and major amputation rate with a patent graft 6%. No technique related problems were noticed. CONCLUSION: Angioscopy guided valvulotomy was safe and simple and allowed good quality control of the veins. The presented results in this study are comparable to other recently reported series of in situ bypass. The clinical use of small flexible endoscopes allows a safe and atraumatic valvulotomy and simultaneous quality control of autologous vein grafts.

Adult↗
PubMed1994

Percutaneous angioscopy in patients with restenosis after excimer laser coronary angioplasty.

Coronary angioscopy was performed in two patients with restenosis after excimer laser coronary angioplasty to improve our knowledge of restenosis after excimer laser angioplasty. The characteristics of the angioscopic findings in restenosis after excimer laser angioplasty consisted of smooth white plaques, which were distinctly different from the yellow plaques commonly observed in primary lesions. These findings indicate that restenosis in these patients after excimer laser angioplasty may be associated with smooth muscle cell proliferation and fibrosis.

Angioplasty, Laser↗
PubMedDate not supplied

Haziness on coronary angiogram after percutaneous transluminal coronary angioplasty evaluated with angioscopy.

Coronary angiograms obtained after percutaneous transluminal coronary angioplasty are often hazy due to uneven distribution of contrast medium at the angioplasty site, In this study, structural changes resulting in haziness after percutaneous transluminal coronary angioplasty were identified angioscopically. The affected coronary arteries of 35 patients who underwent successful percutaneous transluminal coronary angioplasty were examined with angioscopy. Coronary angioscopic examination of the sites subjected to percutaneous transluminal coronary angioplasty revealed large surface disruptions in 17 cases, small surface disruptions in four cases, and thrombi in 24 cases. Angiographic haziness was recognized in 24 of 35 patients after percutaneous transluminal coronary angioplasty. Haziness on angiography was more significant in patients who exhibited large surface disruption (88% vs 50%, p < 0.05), and was significantly greater in patients who exhibited white thrombus (100% vs 56%, p<0.05). Moreover, it appears that percutaneous transluminal coronary angioplasty-induced large surface disruption and white thrombus likely play an important role in increasing haziness.

Adult↗
PubMedDate not supplied

When does atherosclerosis become irreversible? Chronological change from an early to an advanced atherosclerotic lesion observed by angioscopy.

Quite a large number of studies on atherosclerosis have been published to date. However, no report on the development and irreversibility of lesions has been published so far. The authors conducted the following experiments to examine in vivo lesions under direct vision. Atherosclerotic lesions were created in 11 Japanese macaques, and progress of the lesions was observed under changing feeding conditions. The efficacy of cholesterol-lowering therapy was also evaluated and the mechanism by which eicosapentaenoic acid (EPA) suppresses atherosclerosis was examined. The results of this long-term study were as follows: (1) Early lesions of atherosclerosis (fatty streaks) developed in the aortic wall owing to cholesterol loading disappeared when the serum concentration of total cholesterol was reduced. (2) Atheromas first developed at the orifices of major branches of the aorta. And even though serum cholesterol was reduced, the lesions gradually spread to nearby areas. (3) After atheromas developed, advancement of the lesions slowed, as assessed by angioscopy, when EPA was administered while cholesterol loading was continued. Thus, early lesions of atherosclerosis are reversible and cholesterol-lowering therapy is an effective treatment; however, since advanced lesions seem to be irreversible, cholesterol-lowering therapy may not be effective for such lesions. The results of angioscopic examination showed that EPA slowed the progression of atheromatous lesions, and probably suppression of the proliferation of smooth muscle cells is the mechanism of such effect.

Angioscopy↗
PubMed2003

Virtual intra-arterial angioscopy (VIA) of the carotid artery based on helical CT data.

The purpose of this study was to visualize both the vessel wall and atherosclerotic plaques in virtual intra-arterial angioscopy (VIA) based on helical CT data sets. To achieve this in vitro, the optimal reconstruction threshold of the vessel wall was determined to be 56.4% of the maximum enhancement. Using this threshold, 20 patients suffering from symptomatic carotid disease were examined in a helical CT scanner. The degree of stenosis was defined using the North American Symptomatic Endarterectomy Trial (NASCET) criteria and compared with results from digital substraction angiography (DSA). Grading of stenoses was only possible by adding the separately computed plaque geometry to the geometry of the vessel wall in a second step. Correlation between VIA and DSA in low grade, medium grade and high grade stenosis was 88%, 93% and 71%, respectively. Complete occlusions were diagnosed correctly in all patients. Sensitivity and specificity for the correct diagnosis of high grade stenosis was 93.7% and 91.3%, respectively. A realistic depiction of intraluminal structures in carotid arteries can only be generated by displaying both the vessel wall and plaque structures simultaneously.

Aged↗
PubMed2003

Unique single coronary artery with acute myocardial infarction: observation of the culprit lesion by intravascular ultrasound and coronary angioscopy.

We report an acute myocardial infarction in a patient with a single coronary artery. The right coronary artery arose from the middle portion in the left anterior descending artery through the transverse branch. This type of single coronary artery has not been previously reported. Moreover, this is the first report in which the culprit lesion in a patient with a single coronary artery was observed by intravascular ultrasound and coronary angioscopy. The patient underwent successful coronary stent deployment.

Adult↗
PubMedDate not supplied

Carbon dioxide column angioscopy: a new endovascular imaging technique.

A new angioscopic technique with a CO(2) gas medium for prolonged viewing sessions in the carotid artery is described. A stationary column of CO(2) gas, angled 17-30 degrees subhorizontally and buoyed against a balloon catheter, can be safely maintained. During 10-20-min sessions in dogs, endothelia, thrombi, stent filaments, coils, and an intimal flap were visualized. This technique eliminates the need for continuous saline infusion, which has prevented the application of angioscopy in the carotid artery.

Angioscopes↗