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At least 19 recordsLinked to original sources
PubMed1979

[Recanalization by catheter of the occluded artery after acute myocardial infarction (transluminal recanalization (author's transl)].

Using guide-wires and special catheters the occluded infarct-related coronary artery was recanalized in 10 patients with acute myocardial infarction 6.6 +/- 7.1 hours after the onset of symptoms. There were no complications. Immediately after recanalization there were 80-95% lesions at the site of the previous occlusion. Angiography, performed in 9 patients in the chronic stage of myocardial infarction, revealed patency of the recanalized vessel in all instances. There was a marked decrease in the narrowing at the time of the second angiogram in 6 patients. Changes in left ventricular function from the acute to the chronic stage were assessed in 8 patients: the ejection fraction increased in 6. The results of this pilot study indicate that transluminal recanalization of acutely occluded coronary arteries is possible without harmful side-effects. Early restoration of flow may salvage the jeopardized myocardium. Further application of this method of treatment in selected patients and efforts to improve the technique seem to be justified.

Adult↗
PubMed1998

Recanalization after coil embolotherapy of pulmonary arteriovenous malformations: study of long-term outcome and mechanism for recanalization.

OBJECTIVE: We investigated the efficacy of steel coils for embolotherapy of pulmonary arteriovenous malformations (PAVMs) by reimaging the embolized PAVMs. CONCLUSION: We found a high incidence (57%; 8/14) of recanalization in PAVMs embolized with steel coils. Contrast-enhanced CT is useful for detection of recanalized PAVMs. Half of the recanalized PAVMs were fed by bronchial artery branches. Thus, coil embolization should be performed as close as possible to the PAVM to avoid future development of bronchial artery-to-pulmonary artery anastomoses that may cause recanalization.

Adolescent↗
PubMed1991

[Reparation of the vascular wall after laser recanalization of the artery (characteristics of changes in the vascular wall at a late period after laser recanalization)].

Chronic experimental studies were carried out on 9 mongrel dogs. To study the reparation processes in the arterial wall after laser intervention, arteries of different anatomic zones were irradiated with laser: descending and abdominal aorta, iliac, femoral and axillary arteries. To make a laser trauma, two types of laser catheters were used: a) with the light guide with diameter of 400 and 600 microns; and b) with a quartz tip at the end. The laser light source was a laser of Cu vapors, and ND; YAG laser. Laser energy was transmitted in the form of individual impulses with the duration of 2-5 sec, and power of 8-10 watt. Histological studies of the preparations of the irradiated arterial wall were performed at periods: 1-3-7-16-28 days, and 2-8 months. Characteristic signs of the vascular wall reparations are given. The analysis of the experimental results showed that by the 28-th day after laser trauma, on the site of laser irradiation a connective tissue scar was formed substituting the defect in the vascular wall and covered from the lumen side with a thin continuous layer of endothelium without any signs of inflammatory infiltration. The development of intimal hyperplasia is not excluded, as well as of inflammatory reaction with the following thrombotic occlusion of the artery lumen. The study results can be used in clinical practice in order to determine the optimum tactics and performance of laser recanalization of the artery, as well as the treatment after the laser intervention.

Angioplasty, Laser↗
PubMed2004

Subintimal versus intraluminal recanalization of chronic iliac occlusions.

PURPOSE: To present our experience with subintimal recanalization of chronic iliac occlusions and retrospectively compare the results of this technique with those of standard intraluminal recanalization. METHODS: A retrospective review was conducted of 98 patients (91 men; mean age 61+/-10 years, range 37-77) with unilateral chronic iliac occlusions who underwent standard intraluminal recanalization or subintimal recanalization if intraluminal wire passage failed. The technical success, complications, and patency rates were statistically compared between groups. RESULTS: In 59 (60%) of 98 patients, the occlusions were successfully crossed with ipsilateral intraluminal recanalization, while failure of intraluminal recanalization in the remaining 39 led to attempted subintimal recanalization (ipsilateral in 17 and antegrade-retrograde in 22). Overall, ipsilateral intraluminal recanalization was technically successful in 56 (57%) of 98 patients; subintimal recanalization was successful in 35 (90%) of 39 patients. Technical success was only 29% in 17 patients who underwent subintimal recanalization via an ipsilateral retrograde approach. During a follow of 27+/-16 months, primary and assisted primary patencies were not significantly different between the patients treated with intraluminal versus subintimal recanalization (p=0.81 and 0.64, respectively). CONCLUSIONS: Subintimal recanalization is a safe and effective supplement to standard intraluminal recanalization techniques in the endovascular treatment of chronic iliac occlusions. Because of the poor outcome associated with the ipsilateral route, subintimal recanalization of these lesions should preferably be performed via a combined antegrade-retrograde approach.

Adult↗
PubMed2003

Is the benefit of early recanalization sustained at 3 months? A prospective cohort study.

BACKGROUND AND PURPOSE: Early arterial recanalization can lead to dramatic recovery (DR) during intravenous tissue plasminogen activator (tPA) therapy. However, it remains unclear whether this clinical recovery is sustained 3 months after stroke. METHODS: We studied consecutive patients treated with intravenous tPA (0.9 mg/kg within 3 hours) who had M1 or proximal M2 middle cerebral artery occlusion on pretreatment transcranial Doppler according to previously validated criteria. Patients were continuously monitored for 2 hours after tPA bolus to determine complete, partial, or no early recanalization with the Thrombolysis in Brain Ischemia (TIBI) flow grading system. A neurologist obtained the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) scores independently of transcranial Doppler results. DR was defined as a total NIHSS score of 0 to 3 points, and early recovery (ER) was defined improvement by > or =10 points at 2 hours after tPA bolus. Good long-term outcome was defined as an NIHSS score of 0 to 2 or an mRS score of 0 to 1 at 3 months. RESULTS: Fifty-four patients with proximal middle cerebral artery occlusion had a median prebolus NIHSS score of 16 (range, 6 to 28; 90% with > or =10 points). The tPA bolus was given at 130+/-32 minutes (median, 120 minutes; 57% treated within the first 2 hours). DR+ER was observed in 50% of patients with early complete recanalization (n=18), 17% with partial recanalization (n=18), and 0% with no early recanalization (n=18) (P=0.025). Overall, DR+ER was observed in 12 patients (22%), and 9 (75%) had good outcome at 3 months in terms of NIHSS (P=0.009) and mRS (P=0.006) scores compared with non-DR and non-ER patients. If early recanalization was complete, 50% of these patients had good outcome at 3 months, and 78% with DR+ER sustained early clinical benefit. If recanalization was partial, 44% had good long-term outcome, and 66% of patients with DR+ER sustained the benefit. If no early recanalization occurred, 22% had good long-term outcome despite the lack of DR within 2 hours of tPA bolus (P=0.046). Mortality was 11%, 11%, and 39% in patients with complete, partial, and no early recanalization, respectively (P=0.025). Reasons for not sustaining DR in patients with early recanalization were subsequent symptomatic intracranial hemorrhage and recurrent ischemic stroke. CONCLUSIONS: DR or ER after recanalization within 2 hours after tPA bolus was sustained at 3 months in most patients (75%) in our study. Complete or partial early recanalization leads to better outcome at 3 months after stroke. Fewer patients achieve good long-term outcome without early recanalization.

Aged↗
PubMed2006

Temporal profile of recanalization after intravenous tissue plasminogen activator: selecting patients for rescue reperfusion techniques.

BACKGROUND AND PURPOSE: Intravenous thrombolysis in stroke achieves arterial recanalization in approximately 50% of cases. Determining temporal profile of recanalization may address patient selection and potential benefits of further rescue reperfusion techniques. METHODS: We studied 179 consecutive intravenous tissue plasminogen activator (t-PA)-treated patients with intracranial artery occlusion. Continuous transcranial Doppler assessed recanalization (none-partial-complete) at 60 minutes (early), 120 minutes (delayed) after t-PA bolus, and 6 hours (late) from symptom onset. Outcomes were determined: National Institutes of Health Stroke Scale (NIHSS; 48-hour NIHSS) and 3-month modified Rankin Scale (mRS). RESULTS: On admission, 68% of patients presented proximal middle cerebral artery occlusion, median NIHSS 17. Early recanalization was complete for 30 patients (17%), partial for 50 (28%), and none for 99 (55%). Delayed recanalization was complete for 56 patients (31%), partial for 39 (22%), and none for 84 (47%). Although early flow improvement was observed in up to 45% of patients, only 19% of patients with persistent occlusion (11% of total) presented delayed recanalization (odds ratio [OR] delayed/early recanalization, 0.16; 95% CI, 0.085 to 0.304; P<0.001). Among patients with persistent occlusion at 2 hours, only 13 (7% of total) presented late flow improvement (OR late/early recanalization, 0.09; 95% CI, 0.043 to 0.196; P<0.001). The few patients with late recanalization presented comparable median 48-hour NIHSS to those with early/delayed recanalization (3 versus 4.5; P=0.9) and much lower than those with persistent occlusion after 6 hours (3 versus 15; P=0.005). At 3 months, the rate of mRS < or =2 was not statistically different between patients with early/delayed versus late recanalization (55% versus 86%; P=0.12) but was lower if occlusion persisted 6 hours after onset (22%; P<0.001). CONCLUSIONS: The majority of t-PA-induced recanalizations occur during the first hour after treatment. Recanalizations during the following hours are rare but still related to clinical improvement if achieved within 6 hours from onset. Rescue reperfusion techniques should be considered if flow improvement is not observed 60 minutes after t-PA bolus.

Adult↗
PubMed2003

Local intra-arterial fibrinolysis in acute hemispheric stroke: effect of occlusion type and fibrinolytic agent on recanalization success and neurological outcome.

BACKGROUND: To evaluate the effect of occlusion type and fibrinolytic agent on recanalization success and clinical outcome in patients undergoing local intra-arterial fibrinolysis (LIF) in acute hemispheric stroke. METHODS: LIF was performed in 137 patients with angiographically established occlusion in the carotid circulation within 6 h of stroke onset. Retrospective analysis included recanalization success, recanalization time, type of occlusion and fibrinolytic treatment mode. Five types of occlusion were categorized: intracranial bifurcation (carotid 'T') of the internal carotid artery (ICA; n = 35); proximal segment of the middle cerebral artery (MCA; n = 66); distal segment of the MCA (n = 20); extracranial ICA with MCA embolism (n = 8); multiple peripheral branches of the anterior cerebral artery and the MCA (n = 8). Neurologic outcome was evaluated after 3 months by Barthel Index (BI) as good (BI >90), moderate (BI 50-90), poor (BI <50) or death. RESULTS: Recanalization was achieved in 74 patients (54%). Mean recanalization time in recanalized patients was 91 min. Neurologic outcome was good in 48 patients (35%), moderate in 34 (25%), poor in 30 (22%) and 25 died (18%). Outcome was significantly better in recanalized than in nonrecanalized patients (p < 0.001). Treatment results were significantly better in proximal and distal MCA occlusion than in carotid 'T' occlusions (p < 0.001). Recanalization success hardly differed between urokinase and rt-PA. Combined treatment with rt-PA and lys-plasminogen tended toward a faster recanalization. Parenchymal hemorrhage occurred in 13 patients (9%). CONCLUSION: The type of occlusion is of high prognostic value for successful fibrinolysis in the anterior circulation. However, recanalization is a time-consuming process even with an intra-arterial approach. Recanalization did not differ between type or dosage of plasminogen activators. Further innovative attempts are warranted towards hastening recanalization time in endovascular acute stroke treatment.

Adolescent↗
PubMed2003

Effect of incomplete (spontaneous and postthrombolytic) recanalization after middle cerebral artery occlusion: a magnetic resonance imaging study.

BACKGROUND AND PURPOSE: Early reperfusion is one of the best predictors of good outcome after acute middle cerebral artery (MCA) occlusion. The purpose of this study was to analyze the frequency and relevance of incomplete recanalization for tissue and clinical outcome. METHODS: From a larger acute stroke database (Kompetenznetzwerk Schlaganfall B5), all patients (n=82) with MCA main stem occlusion (excluding carotid T-occlusions) were selected. These patients had received a multiparametric stroke MRI protocol including diffusion- and perfusion-weighted imaging (DWI, PWI) and MR angiography (MRA) within 6 hours after symptom onset, at day 1 and after 1 week. Recanalization status was determined with MRA on day 1 (according to Thrombolysis In Myocardial Infarction flow grades) and used to group patients into those with persistent occlusion (0) or minimal (1), partial (2), or complete (3) recanalization. RESULTS: Incomplete recanalization according to MRI criteria was found in 39 patients (grade 1: n=20; grade 2: n=19), complete recanalization in 10, and persistent occlusion in 33. There was no statistically significant difference in any of the clinical (National Institutes of Health Stroke Scale score) or MRI baseline parameters (DWI lesion, PWI deficit, mismatch volume, mismatch ratio). However, lesion growth was smaller in patients with recanalization (even in patients with only minimal recanalization) and outcome was related to the degree of recanalization (mean modified Rankin score at 90 days: 3.36, 2.70, 1.79, and 1.44 for the groups with no, minimal, partial, and complete recanalization, respectively). Both incomplete and complete recanalization was more frequent in patients receiving thrombolysis. CONCLUSIONS: Incomplete recanalization on day 1 is a frequent MR finding after MCA main stem occlusion, indicating a more favorable clinical course than persistent occlusion. MR indicators of early recanalization could be useful surrogates of efficacy in thrombolytic trials.

Adult↗
PubMed1991

Design and evaluation of a fiberoptic fluorescence guided laser recanalization system.

Current angioplasty techniques for recanalization of totally occluded arteries are limited by the inability to cross the occlusion and by the risk of perforation. A fiberoptic fluorescence guided laser recanalization system was developed and evaluated in vitro for recanalization of 17 human femoral or tibial totally occluded arterial segments (length 1.9-6.8 cm, diameter 2.5-6.0 mm). A 400 or 600 micron silica fiber was coupled to a helium-cadmium laser (lambda = 325 nm) for fluorescence excitation and to a holmium: YAG laser (lambda = 2.1 micron) for tissue ablation. Fluorescence was recorded during recanalization after every other holmium laser pulse. During recanalization, each arterial segment was bent 30-90 degrees with respect to the fiber to simulate arterial tortuosity. Ablation continued with fiber advancement as long as the fluorescence confirmed that the target tissue was atherosclerotic. Arterial spectra were classified as normal or atherosclerotic by an on-line computerized fluorescence classification algorithm (sensitivity 93%, specificity 95%). Normal fluorescence necessitated redirection of the fiber greater than 30 times per segment to continue recanalization. Fifteen of 17 totally occluded arteries had multiple recanalization channels created following total energy delivery of 40-1,016 Joules per segment with no angiographic or histologic evidence of laser perforation. Two heavily calcified arterial occlusions were not recanalized due to inhibition of holmium: YAG laser ablation by the recording of normal fluorescence spectra. Therefore, this fluorescence guided laser recanalization system appears safe and effective for recanalization of totally occluded arteries and merits in vivo evaluation. However, the lower sensitivity of fluorescence detection of heavily calcified plaques may limit the efficacy (but not safety) of fluorescence guided recanalization of heavily calcified occlusions.

Angioplasty, Laser↗
PubMed2004

Recanalization of arterial thrombus, and inhibition with beta-radiation in a new murine carotid occlusion model: MRNA expression of angiopoietins, metalloproteinases, and their inhibitors.

BACKGROUND: Recanalization is an important physiologic phenomenon because it can efficiently reestablish circulation after thrombosis. We attempted to characterize molecular events related to recanalization or organization of arterial thrombus in a new murine model by studying genes reported to be involved in angiogenesis or neointima formation. METHODS: Platinum coils, radioactive phosphorus 32 coils or not, were implanted in the carotid artery in mice to cause thrombotic occlusion. The outcome of the occlusion was followed up with transmyocardial angiography and pathologic analysis at 2, 6, or 15 days. Angiographic results were compared with the Pearson chi2 test. Messenger RNA expression of von Willebrand factor (vWF); smooth muscle alpha-actin (SMA+); platelet endothelial cell adhesion molecule-1 (PECAM-1); vascular endothelium cadherin (VE-Cad); endothelial nitric oxide synthase (eNOS); vascular cell adhesion molecule-1 (VCAM-1); tumor necrosis factor alpha (TNF-alpha); matrix metalloproteinase (MMP-9, MMP-12, and MMP-14), and tissue inhibitors of MMPs (TIMPs: TIMP-1, TIMP-2, TIMP-3, TIMP-4); angiopoietins (Ang-1, Ang-2); and receptors Tie-1 and Tie-2, were analyzed with reverse transcriptase polymerase chain reaction 2, 6, and 15 days after surgery. Levels of mRNA expression were compared with analysis of variance and the Student t test. RESULTS: Carotid arteries implanted with nonradioactive 0.015-caliber coils were occluded in 84% of arteries on day 2, but in only 57% of arteries on day 15, which confirms that recanalization occurred in this model. Arteries implanted with 0.015-caliber 32P coils did not become recanalized, and 100% were occluded on day 15 (n = 13; P = .006). Recanalization was associated with endothelial-like cell-lined channels, whereas persistent occlusion was caused by complete filling of the lumen with conjunctive tissue. Coil occlusion, with or without recanalization, was followed by decreased expression of vWf, VE-Cad, eNOS, VCAM-1, MMP-2, TIMP-1, and TIMP-2; stable expression of PECAM-1, SMA+, and TIMP-3; and overexpression of Ang-1 and Ang-2, MMP-9, MMP-14, and TIMP-4. Statistically significant differences when arteries were implanted with 32P coils included decreased expression of TIMP-4 (P = .011) and increased expression of MMP-9 (P = .02). CONCLUSION: Recanalization and organization of arterial thrombus is associated with expression of genes involved in angiogenesis and neointima formation. Recanalization can be prevented with beta-radiation, but molecular mechanisms remain to be refined. CLINICAL RELEVANCE: A better understanding of molecular mechanisms involved in angiogenesis has permitted its regulation as a new option in treatment of various diseases. Inhibition of angiogenesis may help control diseases such as cancer, arthritis, or diabetes retinopathy. On the other hand, stimulation of angiogenesis may palliate conditions associated with insufficient blood supply, such as ischemic heart disease or critical limb ischemia. Yet little is known regarding recanalization (to be differentiated from thrombolysis), a cellular process that occurs concurrently with thrombus "organization." Recanalization is an important physiologic phenomenon because it can efficiently reestablish antegrade circulation after thrombosis both in veins and in arteries, and could be modulated for therapeutic purposes. Thus our efforts at better understanding of mechanisms involved in recanalization could be used, in addition to its promotion to recover flow after thrombotic occlusions, to prevent its occurrence after endovascular interventions designed to permanently occlude aneurysms.

Angiography↗
PubMed2000

Timing of recanalization after tissue plasminogen activator therapy determined by transcranial doppler correlates with clinical recovery from ischemic stroke.

BACKGROUND: The duration of cerebral blood flow impairment correlates with irreversibility of brain damage in animal models of cerebral ischemia. Our aim was to correlate clinical recovery from stroke with the timing of arterial recanalization after therapy with intravenous tissue plasminogen activator (tPA). METHODS: Patients with symptoms of cerebral ischemia were treated with 0.9 mg/kg tPA IV within 3 hours after stroke onset (standard protocol) or with 0.6 mg/kg at 3 to 6 hours (an experimental institutional review board-approved protocol). National Institutes of Health Stroke Scale (NIHSS) scores were obtained before treatment, at the end of tPA infusion, and at 24 hours; Rankin Scores were obtained at long-term follow-up. Transcranial Doppler (TCD) was used to locate arterial occlusion before tPA and to monitor recanalization (Marc head frame, Spencer Technologies; Multigon 500M, DWL MultiDop-T). Recanalization on TCD was determined according to previously developed criteria. RESULTS: Forty patients were studied (age 70+/-16 years, baseline NIHSS score 18.6+/-6.2). A tPA bolus was administered at 132+/-54 minutes from symptom onset. Recanalization on TCD was found at the mean time of 251+/-171 minutes after stroke onset: complete recanalization occurred in 12 (30%) patients and partial recanalization occurred in 16 (40%) patients (maximum observation time 360 minutes). Recanalization occurred within 60 minutes of tPA bolus in 75% of patients who recanalized. The timing of recanalization inversely correlated with early improvement in the NIHSS scores within the next hour (polynomial curve, third order r(2)=0.429, P<0.01) as well as at 24 hours. Complete recanalization was common in patients who had follow-up Rankin Scores if 0 to 1 (P=0.006). No patients had early complete recovery if an occlusion persisted for >300 minutes. CONCLUSIONS: The timing of arterial recanalization after tPA therapy as determined with TCD correlates with clinical recovery from stroke and demonstrates a 300-minute window to achieve early complete recovery. These data parallel findings in animal models of cerebral ischemia and confirm the relevance of these models in the prediction of response to reperfusion therapy.

Aged↗
PubMed1990

Temperature monitoring during peripheral thermo-optical laser recanalization in humans.

To determine probe temperature required to achieve laser thermal recanalization of human peripheral arteries, temperature was monitored at the probe tip using a K-type thermocouple and displayed on a computer screen in real-time in 21 procedures. Recanalization was performed using a Spectraprobe-PLR delivering both laser light and heat in patients with prolonged ischemic limb symptoms. Laser recanalization of totally occluded peripheral arteries (occlusion length = 5.3 +/- 3.8 cm) was done percutaneously (17 procedures) or intraoperatively (4 procedures), after unsuccessful attempts of recanalization using standard guide wire and balloon angioplasty techniques. Probes were activated using argon laser irradiation starting at 5 W and increased by 1-W increments until successful recanalization, or up to a maximum of 12 W. Laser recanalization was achieved in 16/21 (76%) procedures at a mean temperature of 178 +/- 120 degrees C (range 64-503 degrees C) and a mean time of 12.4 +/- 14.1 s. Eleven of the 16 (69%) recanalizations occurred at probe temperature lower than 160 degrees C. Recanalization was achieved at a mean power of 7 +/- 2 W. Perforation occurred in 6 arteries at peak probe temperatures ranging from 73 to 502 degrees C. Perforations occurred in 4 of 6 densely calcific vessels which required high probe temperatures (greater than 250 degrees C). An important feature of temperature monitoring was the immediate detection of probe dysfunction. Although recanalization temperature had a wide range, the majority of recanalizations occurred at probe temperature below 160 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1998

Early complete recanalization in internal carotid artery embolism treated with high-dose t-PA: a sequential angiographic study in a novel model of embolism in rats.

Complete early recanalization rate of human internal carotid artery embolic occlusion treated with thrombolytic drugs is low. To study factors related with this difficulty to recanalize we have developed a novel model of rat ica embolism using a fragment of human embolus. In 50 male Wistar rats the ica was embolized through the external carotid artery with a fragment of an embolus obtained from a human embolectomy passed through a catheter of 0.8 mm diameter. Recanalization was assessed by sequential angiograms from 15 to 120 min after embolization. Reperfusion was classified according to TIMI grades. Emboli of either 1 (group 1) or 2 mm (group 2) in length were cut. In group 1, four groups of nine animals each were treated, 15 min after embolization, with i.v. t-PA at doses of 1 mg/kg, 10 mg/kg and 20 mg/kg or saline. In group 2 there was one control group of seven animals treated with saline and another of seven animals treated with 10 mg/kg t-PA. Complete recanalization (TIMI grade 3) within the first 30 min was present in two animals treated with 10 and 20 mg/kg. Complete recanalization within the first 60 min was present in 0% of controls and animals treated with 1 mg/kg and in 44% of the 10 and 20 mg/kg groups (P<0.05 in chi-square test). Incomplete recanalization (TIMI grades 0, 1 and 2) occurred in 33%. In group 2 total recanalization occurred in 1/7 controls and in 3/7 animals receiving 10 mg/kg of t-PA. Early (60 min) complete i.v. t-PA induced internal carotid artery embolic recanalization is low with standard doses and increases moderately when high doses are used. Further increases in the dose do not improve recanalization rate, which is not clearly influenced by embolus size. Complete recanalization within 30 min, the period after which infarction develops in the rat, is uncommon in our model.

Angiography↗
PubMed2004

Differential pattern of tissue plasminogen activator-induced proximal middle cerebral artery recanalization among stroke subtypes.

BACKGROUND AND PURPOSE: We aimed to evaluate the timing, speed, and degree of tissue plasminogen activator (tPA)-induced recanalization in patients with proximal middle cerebral artery (MCA) occlusion of different stroke subtypes. METHODS: We evaluated 72 patients with acute stroke caused by proximal MCA occlusion treated with intravenous tPA in <3 hours. Transcranial Doppler monitoring of recanalization was conducted during tPA infusion and at 6 hours. Strokes were categorized as large-vessel disease strokes, cardioembolic strokes, or strokes of undetermined origin according to Trial of Org 10172 in Acute Stroke Treatment criteria. RESULTS: During 1-hour tPA infusion, recanalization occurred in 34 patients (47%); 32% showed a sudden, 50% showed a stepwise, and 18% showed a slow pattern of recanalization. One-hour recanalization was more frequent in patients with cardioembolic stroke (59%) compared with large-vessel disease (8%) and undetermined origin (50%) strokes. A cardiac source of emboli was identified in 81% of patients who showed a sudden clot breakup during tPA infusion. Rate of complete recanalization at 6 hours was higher (P=0.006) in patients with cardioembolic stroke (50%) compared with other stroke subtypes (27%). Sudden recanalization was associated (P=0.002) with a higher degree of neurological improvement at 24 hours compared with stepwise, slow, and no recanalization. A graded response in long-term outcome was observed in relation to the speed of clot lysis during tPA administration. CONCLUSIONS: We demonstrate that the pattern of tPA-induced MCA recanalization differs among stroke subtypes. Early recanalization was more frequent, faster, and more complete in patients with cardioembolic stroke compared with other stroke subtypes.

Acute Disease↗
PubMed2005

Blood pressure and vessel recanalization in the first hours after ischemic stroke.

BACKGROUND AND PURPOSE: Transient elevation of arterial blood pressure (BP) is frequent in acute ischemic stroke and may help to increase perfusion of tissue jeopardized by ischemia. If this is true, recanalization may eliminate the need for this BP elevation. METHODS: We analyzed BP in 149 patients with acute ischemic stroke on admission to the hospital and 1 and 12 hours after intraarterial thrombolysis. BP values of patients with adequate recanalization were compared with BP values of patients with inadequate recanalization. Recanalization was determined on cerebral arteriography after thrombolysis using thrombolysis in myocardial infarction grades. RESULTS: Systolic, mean, and diastolic arterial BP decreased significantly from admission to 12 hours after thrombolysis in all patients (P<0.001). Before thrombolysis, patients with adequate and inadequate recanalization showed equal systolic (147.4 and 148.0 mm Hg), mean (102.1 and 104.1 mm Hg), and diastolic (79.5 and 82.1 mm Hg) BP values. Twelve hours after thrombolysis, patients with adequate recanalization had lower values than those with inadequate recanalization (systolic BP, 130 versus 139.9 mm Hg; mean BP, 86.8 versus 92.2 mm Hg; and diastolic, BP 65.2 versus 68.3 mm Hg). Two-way repeated ANOVA analysis showed a significant group x time interaction for systolic BP, indicating a larger systolic BP decrease when recanalization succeeded (P=0.019). CONCLUSIONS: The course of elevated systolic but not diastolic BP after acute ischemic stroke was found to be inversely associated with the degree of vessel recanalization. When recanalization failed, systolic BP remained elevated longer than when it succeeded.

Adult↗
PubMed2003

Effect of recanalization of chronic total occlusions on global and regional left ventricular function in patients with or without previous myocardial infarction.

Previous studies have demonstrated improvement of regional wall motion and global left ventricular function after successful recanalization of chronic total occlusion in coronary artery. However, the difference of benefits of recanalization between infarct site and noninfarct site is unknown. This study assessed the changes in left ventricular ejection fraction, regional wall motion after successful angioplasty of chronic total occlusions with or without previous myocardial infarction. This study also evaluated the factors that influenced the outcome of left ventricular function. We retrospectively studied 75 patients with a successfully recanalized chronic total occlusion in native coronary artery. Left ventriculograms were obtained at baseline and after 6 months. Global and regional left ventricular function were determined. The patients were divided into two groups. Group 1 comprised patients without previous myocardial infarction in the territories of total occlusion vessel that was recanalized. Group 2 comprised patients with previous myocardial infarction in the territories of total occlusion vessel that was recanalized. Left ventricular ejection fraction increased from 53.2% +/- 16.3% at baseline to 57.3% +/- 20.1% at 6-month follow-up in the whole group (P = 0.001). In group 1 patients, the evolution of left ventricular (LV) ejection fraction increased from 59.5% +/- 13.7% to 67.3% +/- 14.6% (P < 0.001). In group 2 patients, the evolution of LV ejection fraction increased, but not significantly, from 48.9% +/- 16.2% to 50.5% +/- 16.9% (P = NS). The evolution of LV ejection fraction increased from 47.6% +/- 17.4% to 50.8% +/- 17.5% (P < 0.05) in the subgroup of recanalization in infarct-related vessel that had rich collateral circulation and had long-term patency. The regional wall motion all significantly improved in group 1 patients (P < 0.05). The regional wall motion did not change in group 2 patients (P = NS). The influence of recanalization of chronic coronary occlusions on the improvement of left ventricular global function was different between myocardial infarction and nonmyocardial infarction patients. The left ventricular function did not improve in myocardial infarction patient. Regional wall motion improved in patients without previous myocardial infarction. For reliable improvement of left ventricular function after recanalization of chronic total occlusions, evidence (not only by symptom or treadmill test) of viable myocardium in recanalized vessel is important. It is also important to keep patency of infarct-related vessel that has good collateral circulation for improving the left ventricular function.

Aged↗