Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Recanalization”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,675 records · Page 93Linked to original sources
PubMed1998

Restoration of coronary blood flow by single bolus injection of the GPIIb/IIIa receptor antagonist c7E3 Fab in a patient with acute myocardial infarction of recent onset.

It has been debated that primary coronary angioplasty could be more effective if immediate antithrombotic therapy would contribute to a faster recanalization of the infarct-related artery. This is the first report of a patient who presented at the emergency department with acute anterolateral myocardial infarction, in whom a single bolus injection of c7E3 Fab (0.25 mg/kg body weight) led to complete reperfusion of the infarct-related coronary artery during organization time for planned acute coronary angioplasty. Pain relief 15 min after initiation of therapy and ST-segment resolution of > 50%, as well as occurrence of idioventricular rhythm 30 min thereafter, were suggestive of successful recanalization before the coronary intervention was started. Diagnostic coronary angiography at 90 min revealed TIMI-grade 3 flow in the infarct-related coronary artery with only moderate luminal irregularities. Bolus administration of c7E3 Fab could be effective for dissolving platelet-rich thrombi in the early stage of acute myocardial infarction (AMI) and may therefore represent a promising "bridging" therapy in patients with AMI elected for primary coronary angioplasty.

Abciximab↗
PubMed1992

Total gastrectomy: nutritional status after different reconstruction techniques. An experimental study.

The authors report their experimental studies on early nutritional changes in 30 gastrectomized rats where intestinal continuity was restored by three different reconstruction methods, i.e., exclusion of the duodenum from alimentary transit (Sweet-Allen method), or duodenal recanalization (Longmire method) or double duodenal and jejunal recanalization (Moricca method). Ten sham operated rats were used as controls. Results showed that the group of rats which underwent Longmire's reconstruction presented better nutritional parameters (body weight gain, daily food intake, feeding efficiency, albuminemia) than the Moricca and Sweet-Allen reconstruction groups. These results became statistically significant when follow up was extended to 18 months by using an actuarial method. However, perioperative mortality rate was highest in the Longmire reconstruction group.

Anastomosis, Surgical↗
PubMed1986

Nd-YAG laser application in pulmonary and endobronchial lesions.

For recurrent pulmonary bleeding and recanalization of centrally obstructed or stenosed airways, endobronchial Nd-YAG laser irradiation through fiberoptic bronchoscopy was performed on 25 patients with malignant (n = 21) and benign (n = 4) disease of tracheobronchial lesions under topical anesthesia. Complete (n = 12) and partial (n = 6) restoration of the airway occurred in all 25 patients after photoresection therapy. For two patients with recurrent bleeding, the therapy resulted in immediate arrest of bleeding. For five patients the therapy resulted in unsuccessful recanalization because of rapidly recurring tumors. Two patients' conditions were complicated by respiratory insufficiency, one caused by smoke intoxication during laser vaporization and the other caused by tenacious rubberlike fibrinous plaque within a day after laser treatment. There was no mortality or perforation of the tracheobronchial wall after laser irradiation. Nd-YAG laser provides an additional tool in the palliative therapy for unresectable, obstructive malignant tumors and a procedure for avoiding extensive surgery in benign lesions.

Adenocarcinoma↗
PubMed1988

Percutaneous, in vivo excimer laser angioplasty: results in two experimental animal models.

Pulsed ultraviolet light from an excimer laser was successfully transmitted via conventional fused silica optical fibers and used to accomplish recanalization of stenotic or totally occluded arteries in an intact, flowing blood field of two atherosclerotic animal models. The fibers, 300-600 micron in diameter, were delivered percutaneously in wire-guided multilumen catheters and then used to transmit wavelengths of 308 or 351 nm from excimer lasers with pulse durations of 12 nsec or less. Lesions from 70-100% diameter narrowing, and 0.6 to 5.5 cm in length were successfully recanalized (less than 50% residual diameter narrowing) in eight animals, using 3-4 J/cm2/pulse, 10-50 Hz, and 48-370-sec cumulative exposure. Necropsy examination in six of the eight animals disclosed no signs of thermal injury. Perforations were observed in four of eight animals. Thus, while use of an excimer laser power source did not obviate vascular perforation as a complication of laser angioplasty, these preliminary results indicate that energies of pulsed ultraviolet light sufficient to ablate atherosclerotic plaque can be both transmitted via conventional fused silica optical fibers and used successfully within an intact, flowing blood field. It may therefore be possible to use pulsed ultraviolet light from an excimer laser to accomplish percutaneous ablation of atherosclerotic arterial obstructions in humans.

Angiography↗
PubMed1988

Percutaneous transluminal excimer laser angioplasty in total peripheral artery occlusion in man.

Laser angioplasty and laser-assisted angioplasty have become a clinical reality. Producing sharply defined borders of the ablated area with minimal adjacent thermal damage, excimer lasers offer several proven and some potential advantages over conventional systems. To evaluate the feasibility of excimer laser angioplasty, we have treated one patient using 308-nm radiation via a bare fiber in direct contact with the total occlusion of a right femoral artery. The lesion was successfully recanalized, thus allowing easy passage of the balloon catheter and subsequent dilatation. This percutaneous laser recanalization of an occluded peripheral artery is one of the first to be done in man using excimer laser radiation, thus demonstrating that the technique is feasible and the system is potentially useful.

Angioplasty, Balloon↗
PubMed1988

Effects of blood flow on laser probe temperature in human arteries.

Laser recanalization using metal capped fibers occurs by thermal vaporization of occluding plaque. However, little is known about the effects of blood and flow on the temperature of the laser probe or the arterial wall during lasing. To study this, probe and arterial wall temperatures were measured while a metal capped fiber, activated by an argon laser, was held stationary in a stenotic human peripheral artery. Arteries were perfused with saline and blood, and flow was varied from 0 to 140 cc/min. Probe temperatures were significantly higher in blood than in saline. However, the increased probe temperature achieved in blood was not transferred to the arterial wall. Increasing flow decreased probe temperature in both media, but again arterial wall temperatures were minimally affected. Thus, the presence of blood and flow may significantly affect heat generation and heat transfer during arterial recanalization using metal capped fibers.

Arteriosclerosis↗
PubMed1989

Effect of CO2 and blood media on laser probe temperature.

Blood may limit laser ablation of arterial plaque by decreasing thermal energy transfer from metal-capped probes to arterial occlusions. Since a gas is a good insulator of heat, CO2 may be a better medium for laser recanalization. To study this possibility, a metal-capped fiber was positioned in a segment of blood-filled polyethylene tubing and activated with an argon laser. Probe temperatures were measured in blood and as the blood was displaced by flowing CO2 gas. Probe temperatures were higher at all powers studied in CO2 gas than in blood. Maximum probe temperatures averaged 518 +/- 24 degrees C after CO2 infusion versus 320 +/- 7 degrees C in blood, (P less than 0.0001). Blood aggregate formation was noted on the probe surface in blood but not in CO2 medium. Thus CO2 gas may be a preferable medium for laser recanalization, since higher probe temperatures are achieved, and the probe surface remains free of insulating blood coagulate.

Angioplasty, Balloon↗
PubMed1994

Bipolar coagulation at different energy levels: effect on patency.

Determining the extent of damage caused by bipolar coagulation at different levels is critical in microsurgery. If no significant damage occurs at known levels, this technique can be used instead of ligation, saving considerable time. One hundred eighty Sprague-Dawley rats were divided into six groups of 30 each. The effects of bipolar coagulation were assessed at either 2 or 10.4 watts at the junction between the common femoral artery and a branch vessel. Three common clinical settings were used: branch coagulation without interruption of blood flow in the common femoral artery; branch coagulation with interruption of blood flow for 30 minutes; and branch coagulation with arterial anastomosis 3-5 mm distal to the branch. Control procedures without coagulation were performed on the contralateral vessels. The animals were re-explored at 5-7 days. No differences occurred in patency of the coagulated vessels at 2 or 10.4 watts of delivered energy as compared with controls. Recanalization of the side branch occurred in approximately 80% (144/180) of specimens. Extensive damage to endothelium, tunica intima, and tunica media occurred for 1-2 mm around the site of the coagulated branch. The forceps pick-up test demonstrated little difference in flow of the cauterized vessel compared with controls. However, the cauterized vessel had a clinically weaker pulse stream of the transected common femoral artery. Recanalization of the coagulated side branch commonly occurred with a fibrin cap at the end of the vessel. Manipulation of the branch vessel frequently caused rebleeding. Our study shows that bipolar coagulation can be used effectively if coagulation is located at least 2 mm from the main vessel.

Animals↗
PubMed1994

Holmium: YAG laser surgery in obliterated cochleas: an experimental study in human cadaver temporal bones.

A pulsed holmium:YAG laser (lambda = 2120 nm) was used to reopen the basal turn of artificially obliterated human cochleas in freshly dissected cadavers. This allowed intracochlear insertion of the stimulation electrode of a cochlear implant under simulated surgical conditions. Laser energy was transmitted through a 400-microns nylon fiber via the opened facial recess directly to the round window niche. At an energy level of 500 mJ per 2.5 microseconds pulse, a repetition rate of 2 Hz, and an exposure time of 20-30 s, the photo-ablative mechanism of laser-bone interaction led to a 8-10 mm recanalization of the basal turn of the cochlea without damaging surrounding structures. The artificial bony occlusion and the recanalized basal turn of the cochlea were visualized by means of computed tomography and studied under light microscopy, using a histologic thin-section technique.

Aluminum Silicates↗
PubMed1996

Evaluation of regional cerebral blood flow using single photon emission tomography for the selection of patients for local fibrinolytic therapy of acute cerebral embolism.

To clarify the indications for local fibrinolytic therapy for acute cerebral embolism, correlation among initial regional cerebral blood flow (rCBF) abnormalities, recanalization timing, and computed tomographic scan (CT) findings two days later were evaluated in 17 cases. All cases included had embolic occlusion of middle cerebral or internal carotid arteries which showed no abnormal findings on initial CT corresponding to the acute events but did show abnormal CBF reduction on initial single photon emission computed tomography (SPECT). Relative rCBF was evaluated as the percentage radioisotope counts in the region of interest (ROI) of the affected side against the corresponding ROI in the unaffected contralateral side. Within 6 hours from onset, there was a tendency towards reversed time dependent tolerance of cortical infarction with residual relative rCBF. Hemorrhagic transformation was observed in one case whose relative rCBF was 35% or less. In 10 patients whose occluded arteries were not recanalized within 6 hours, cortical areas with residual relative rCBF of 70% or more did not develop infarction. In conclusions, a pre-therapeutic rCBF study using SPECT is considered to be mandatory: cases with moderate ischemia involving the cortex with residual relative rCBF of between 35% and 70% may be good candidates for local fibrinolytic therapy.

Aged↗
PubMed1984

Delayed reversal of vertebral artery blood flow following percutaneous transluminal angioplasty for subclavian steal syndrome.

Twelve patients suffering from subclavian steal syndrome of various severity due to either proximal subclavian stenoses (10 cases) or subclavian occlusion (2 cases) were treated with percutaneous transluminal angioplasty (PTA). Olbert's dilatation catheters were used. The occlusions could neither be recanalized by the transfemoral nor transaxillary approach. In one right-sided subclavian stenosis an additional distal subclavian occlusion prevented proper placement of the catheter. All the other patients were treated successfully with no re-occlusion during a follow-up period of 1 to 7 months. In one patient, a transient embolic occlusion of the finger arteries was seen following post-interventional repeat angiography. Before, during and after PTA, continuous ultrasound monitoring of the homolateral vertebral flow patterns revealed an unexpected "delay" phenomenon. Despite sufficient recanalization of the proximal subclavian artery, the flow direction within the vertebral artery did not immediately change to antegrade but rather did so gradually within 20 s up to several minutes. This delay of flow-reversal is thought to serve as a protective mechanism against cerebral embolism during, and shortly after PTA of the subclavian artery. Relying on Doppler ultrasound findings, a staging of the subclavian steal is proposed in order to allow adequate selection of patients for PTA.

Adult↗
PubMed1992

Embolization of intracranial arteriovenous malformations and fistulas with polyvinyl alcohol particles and platinum fibre coils.

In order to reduce the recanalization rate of arteriovenous malformations and multiple dural arteriovenous fistulas, embolization was carried out with polyvinyl alcohol (PVA) particles combined with platinum fibre coils in 20 patients. The malformation was occluded more effectively than by PVA alone. Distal deposition of the emboli was obtained by improved steerable catheters (Tracker-18-unibody) and guidewires. The complication rate was lower than usually reported from studies using glue as embolic agent. It was concluded that the combination of PVA and fibre coils enhances the safety and effectiveness of embolization therapy and reduces the frequency of recanalization of intracranial AVMs.

Adult↗
PubMed1991

Palliation of esophageal cancer--operative resection versus laser and afterloading therapy.

Since 1985, 71 patients with end-stage esophageal cancer have been treated either by surgical (n = 26) or endoscopic laser palliation (n = 45). In 16 of 45 patients treated by endoscopy, additional radiotherapy (extrenal and endoluminal irradiation) was performed. Surgery and Nd:YAG recanalization were initially effective in removing the malignant obstruction in 80% of cases. There were no significant differences in survival in either group. The stenosis-free interval was longer in patients who underwent surgery: 24 weeks; minimal stenosis-free interval: 20 weeks. Local recurrences occurred earlier in the endoscopic study group (mean survival: 36 weeks; minimal stenosis-free interval: 20 weeks). Most stenoses successfully underwent further laser treatment. Although only 35% of patients treated endoscopically underwent additional afterloading therapy, this treatment appears to prolong palliation (mean survival: 38 weeks; minimal stenosis-free interval: 36 weeks). A few patients bled after endoscopy and were treated conservatively. The most important complication in the afterloading group was esophagobronchial perforation, which caused one death in our series. Transient pulmonary problems were the most common complication (31%) in the surgical group with a hospital mortality of 19%. Overall, the improvement in the quality of life after surgery was better. However, our results show that Nd:YAG recanalization and afterloading therapy are effective therapeutic alternatives in patients unfit for surgery.

Brachytherapy↗
PubMed1990

[May the internal iliac artery in the pelvic area be ligated in situ bilaterally for hemostasis? Indications and contraindications].

The bilateral ligation of the internal iliac arteries in situ is successful in preventing haemostasis and the treatment of potentially lethal haemorrhage. In spite of using a resorbable thread (catgut) for ligation a complete recanalization of this large artery could only be observed after nine months in an animal experiment. Clinically this ligation of the artery in situ without severance has not impaired erective potency in patients with an otherwise healthy vascular system. Since many patients did not show any disturbance prior to the vessel's recanalization the early established parallel circulation is sufficient to compensate for the perfusion deficit. A contraindication for the ligation is a previous major procedure, especially, in cases of irradiation or an occlusive vascular disease.

Adult↗
PubMed1985

Quantitation and serial section observations of focal venocclusive lesions of hepatic veins in liver cirrhosis.

The pathogenesis and functional significance of the venocclusive (VO) lesions in small hepatic veins occurring in liver cirrhosis, remain controversial. The present study, using quantitative examination and serial sections has disclosed that these lesions are present in 71.7% of 106 autopsy livers with alcoholic, HBsAg-positive, biliary or cryptogenic cirrhosis. The lesions were usually focal: their number in a liver section (10 cm2) was below 15 in 86.7% of the livers having them. The incidence and morphology of the lesions appeared similar in cirrhotic livers with different aetiology. Serial sections disclosed that the affected veins disappeared within the fibrous stroma at one side and were directly connected with the patent larger hepatic veins at other side, indicating that these veins had lost their function as a draining vein of the hepatic parenchyma. In addition, there was frequent recanalization within the VO lesions, and the recanalized vessels frequently communicated with neighboring thin-walled veins in cirrhotic stroma, suggesting an intrahepatic vein to vein anastomosis. In conclusion, VO lesions, when focal, may themselves be responsible to a lesser degree for obstruction of hepatic venous outflow in liver cirrhosis.

Adult↗
PubMed1992

Haemodynamic studies in early stroke.

We investigated prospectively a consecutive series of 81 patients suffering from acute middle cerebral artery (MCA) ischaemia by transcranial Doppler ultrasonography (TCD) within 24 h of the onset of symptoms. To monitor the haemodynamic changes follow-up recordings were carried out at short intervals during the next 2-3 weeks until stable haemodynamic status was achieved. In order to estimate the value of early TCD examinations in predicting the extent of brain damage seen later on, initial MCA flow reduction was correlated with infarction size and pattern on computed tomography. Fifty-three cases showed sufficient ultrasound penetration through the temporal bone. MCA flow asymmetries were recorded in 45 patients (85%); occlusion was observed in 17. Recanalization occurred in 11 patients followed by transient hyperaemia in 3, leaving residual stenosis in 2. Initial increase of flow velocities normalized within days or weeks in 7 out of 9 patients, while 2 developed residual MCA stenosis. Nineteen patients showed a considerable flow reduction on admission, which returned to normal in 9; transient hyperaemia was detected in 5 of these. Eight patients did not show any MCA flow asymmetry. Our study revealed very variable haemodynamic changes in acute stroke, which influenced further diagnostic and therapeutic management. The high rate of spontaneous recanalizations of MCA occlusions followed by transient hyperaemia in many cases has an important bearing on thrombolytic or rheological therapy. Flow velocity differences could be related to infarction pattern rather than to infarction volume. Early MCA flow asymmetry recorded by TCD within the first 24 h could not reliably predict the extent of persistent brain damage or clinical outcome.

Blood Flow Velocity↗
PubMed2000

Two Different Therapeutic Modalities in the Treatment of the Upper Extremity Deep Vein Thrombosis: Preliminary Investigation With 20 Case Reports.

Primary or secondary axillary or/and subclavian vein thrombosis (ASVT) can produce long-term disability, mostly in young patients, while the final vein recanalization after various therapeutic modalities often fails. Our aim was to compare the results of two different therapeutic modalities: the thrombolytic vs anticoagulant therapy, in primary and secondary ASVT in a retrospective data analysis in terms of efficacy, negative side effects, long-term positive results. Eleven patients (Group A), with primary and secondary to central venous cannulation or cardiac pacing ASVT, were treated with anticoagulant therapy, while another 9 patients (Group B), were treated with thrombolytic therapy, that included urokinase or streptokinase for 24-48 hours. The phlebographic, duplex ultrasonographic findings and clinical improvement were compared between the two patient groups. In Group A patients, after a mean period of 81.7 months follow-up (range 58-106), one patient with open vein were noticed, while in Group B patients after a mean follow up period of 52.1 months (range 35-68) five patients presented with recanalized veins (P = 0.040). Complete clinical recovery and vein patency was achieved in one Group A patient, contrary to 5 Group B patients (P = 0.040). When the patients with complete clinical recovery were combined with those who presented some clinical improvement, four Group A patients and eight Group B had satisfactory outcome (P = 0.028). Thrombolytic therapy should be the treatment of choice in primary and secondary ASVT, in productive patients whose lifestyle depends on continued strenuous use of the involved limb with a reasonable medium-term life expectancy. The thrombolytic agents prevent the vein valves damage and malfunction, avoiding re-thrombosis related to venous reflux and stasis, preserving the valve functional integrity.

Journal Article↗
PubMed2000

The Use of Vascular Stents in the Treatment of Iliac Artery Occlusion.

To evaluate our experience of selective iliac artery stenting for total occlusions, a prospective observational study of 25 patients with an occluded iliac artery was designed to run from January 1996-May 1997. Exclusion criteria were an occlusion extended to the femoral artery, claudication Grade III or IV, according to the standards for reports dealing with lower extremity ischemia, and vascular (bypass) surgery in the past. Complete recanalization and selective stent placement was possible in all patients. No complications occurred. In one patient re-stenosis happened inside the stent after a year. Percutaneous reintervention was performed with success. The mean ankle-brachial pressure increased from 0.46 before the procedure to 0.95 after the procedure. After two years of follow-up, the mean ankle-brachial pressure is 0.93. The clinical stage improved by at least one grade to Grade 0 (Rutherford classification). The overall probability of patency for occluded iliac arteries in this study was 95% after two years. Recanalization, followed by percutaneous transluminal angioplasty (PTA) in the treatment of iliac artery occlusions, is our first choice of intervention, considering the absence of complication and satisfactory patency rates in patients with claudication Grade I or II.

Journal Article↗