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Ischemic stunning of the brain: early recanalization without immediate clinical improvement in acute ischemic stroke.

BACKGROUND AND PURPOSE: Early arterial recanalization (ER) with intravenous tissue plasminogen activator (tPA) can lead to dramatic clinical recovery, whereas some patients do not experience immediate clinical improvement. METHODS: Consecutive patients received tPA 0.9 mg/kg IV within 3 hours after symptom onset. All had M1 or M2 middle cerebral artery occlusions on pretreatment transcranial Doppler. Patients were continuously monitored for 2 hours after bolus. ER was defined as the Thrombolysis in Brain Ischemia intracranial flow increase by >or=1 grade. Stroke severity (National Institutes of Health Stroke Scale [NIHSS]) and recovery (modified Rankin Scale) were assessed independently of transcranial Doppler. RESULTS: One hundred twenty patients (mean age, 68+/-15 years; 63 women; median NIHSS, 17; range, 5 to 29; 90% with >or=10 points) received tPA at a median of 120 minutes, 50% within the first 2 hours. ER was observed in 73 patients (32 complete, 41 partial). No immediate clinical changes (n=23) or worsening (by 1 to 6 points on NIHSS, n=4) was observed in 37% of ERs (nonresponders). Complete ER was found in 8 of these 27 patients. At 24 hours, 22 of 27 patients (82%) had persisting deficits of NIHSS >or=10 points, yet 37% of these nonresponders (10 of 27) still achieved good outcome (modified Rankin score, 0 to 2) at 3 months. Among nonresponders with good outcome, 100% had detectable residual flow signals, and 70% had compensatory flow diversion on prebolus transcranial Doppler compared with 65% and 29% of nonresponders with poor outcome (P<0.05). Compared with responders (n=46), nonresponders had similar prebolus median NIHSS of 16 to 17 points, bolus times of 120 to 132 minutes, median speed of thrombolysis (30 minutes), and ER times of 190 to 193 minutes after onset. Reocclusion occurred in 3 of 4 patients with clinical worsening, 30% of other nonresponders, and 22% of responders. Symptomatic hemorrhage rate was 4% in both groups. At 3 months, mortality was 33% in nonresponders compared with 9% in responders (P=0.001). CONCLUSIONS: After successful arterial ER with tPA therapy, lack of early clinical changes or worsening is relatively common (37%) and appears to be independent of time to tPA bolus or reperfusion. However, with tPA alone, at least one third of these nonresponders still achieved good outcomes at 3 months, suggesting the possibility of a "stunned brain" syndrome with delayed recovery. Several different mechanisms may potentially account for this phenomenon.

Acute Disease↗

Combined intravenous and intra-arterial recanalization for acute ischemic stroke: the Interventional Management of Stroke Study.

BACKGROUND AND PURPOSE: To investigate the feasibility and safety of a combined intravenous (IV) and intra-arterial (IA) approach to recanalization in patients with ischemic stroke. MATERIALS AND METHODS: Subjects ages 18 to 80 with an NIH Stroke Scale (NIHSS) > or =10 at baseline had IV recombinant tissue plasminogen activator (rt-PA) started (0.6 mg/kg, 60 mg maximum over 30 minutes) within 3 hours of onset. Additional rt-PA was then administered via microcatheter at the site of the thrombus up to a total dose of 22 mg over 2 hours of infusion or until thrombolysis. Primary comparisons were with similar subsets of placebo and rt-PA-treated subjects from the NINDS rt-PA Stroke Trial. RESULTS: The 80 subjects had a median baseline NIHSS score of 18. The median time to initiation of IV rt-PA was 140 minutes as compared with 108 minutes for placebo and 90 minutes for rt-PA-treated subjects in the NINDS rt-PA Stroke Trial. The 3-month mortality in Interventional Management Study (IMS) subjects (16%) was numerically lower but not statistically different than the mortality of placebo (24%) and rt-PA-treated subjects (21%) in the NINDS rt-PA Stroke Trial. The rate of symptomatic intracerebral hemorrhage (6.3%) in IMS subjects was similar to that of rt-PA-treated subjects (6.6%) but higher than the rate in placebo-treated subjects (1.0%, P=0.018) in the NINDS rt-PA Stroke Trial. IMS subjects had a significantly better outcome at 3 months than NINDS placebo-treated subjects for all outcome measures (odds ratios > or =2). CONCLUSIONS: A randomized trial of standard IV rt-PA as compared with a combined IV and IA approach is needed.

Acute Disease↗

Predictors of early arterial reocclusion after tissue plasminogen activator-induced recanalization in acute ischemic stroke.

BACKGROUND AND PURPOSE: We aimed to determine clinical and hemodynamic predictors of early reocclusion (RO) in stroke patients treated with intravenous tissue plasminogen activator (tPA). METHODS: We studied 142 consecutive stroke patients with a documented middle cerebral artery (MCA) occlusion treated with intravenous tPA. All patients underwent carotid ultrasound and transcranial Doppler (TCD) examination before tPA bolus. National Institutes of Health Stroke Scale (NIHSS) scores were performed at baseline and serially for <24 hours. TCD monitoring of MCA recanalization (RE) and RO was performed during the first 2 hours after tPA bolus and repeated when clinical deterioration occurred <24 hours after documented RE in absence of intracranial hemorrhage. RESULTS: After 1 hour of tPA administration, RE occurred in 84 (61%) patients (53 partial, 31 complete). Of these, 21 (25%) patients worsened after an initial improvement and 17 (12%) of them showed RO on TCD. RO was identified at a mean time of 65+/-55 minutes after documented RE. RO was associated (P=0.034) with a lower degree of 24-hour NIHSS score improvement than sustained RE, and a higher modified Rankin scale score at 3 months (P=0.002). Age older than 75 years (P=0.012), previous antiplatelet treatment (P=0.048), baseline NIHSS score >16 points (P=0.009), higher leukocytes count (P=0.042), beginning of RE <60 minutes after tPA bolus (P=0.039), and ipsilateral severe carotid stenosis/occlusion (P=0.001) were significantly associated with RO. In a logistic regression model, NIHSS score >16 at baseline (odds ratio [OR], 7.1; 95% CI, 1.3 to 32) and severe ipsilateral carotid disease (OR, 13.3; 95% CI, 3.2 to 54) remained as independent predictors of RO. CONCLUSIONS: Stroke severity and ipsilateral severe carotid artery disease independently predict RO after tPA-induced MCA RE.

Adult↗

Endovascular recanalization therapy in acute ischemic stroke.

BACKGROUND AND PURPOSE: To assess the outcome in acute ischemic stroke patients not eligible for systemic thrombolysis (outside the 3-hour time window, after surgery, or on anticoagulant) undergoing endovascular recanalization therapy (ERT) at the Columbia University Medical Center (CUMC) and to determine US nationwide usage and outcome of ERT in acute ischemic stroke. METHODS: Patients treated at CUMC from 2001 to 2004 and the Nationwide Inpatient Sample (NIS) comprising 20% of all admissions in the United States from 1999 to 2002 were analyzed retrospectively. RESULTS: Thirty-one patients underwent ERT. Mean age was 68+/-14 years, 68% were female, and 45% nonwhite (occlusion sites: internal carotid artery 29%; middle cerebral artery 39%; posterior circulation 32%). Pharmacological or mechanical ERT was initiated beyond 3 hours after symptom onset (median time 4.4 hours) in 61%, 29% had surgery, and 39% were on anticoagulant medication. At discharge, 32% had modified Rankin Scale scores of 0 to 2 (52% discharged home or to rehabilitation facilities); overall mortality was 29%, of which 19% were fatal intracerebral hemorrhages. From the NIS cohort, 477 patients (0.17% of all strokes and 14% of all thrombolysis cases) underwent ERT. Fifteen percent died, and approximately 50% were discharged home or to rehabilitation facilities. Intracerebral hemorrhage occurred in 6%. Fewer good outcomes of the CUMC cohort may be explained by more unfavorable premorbid patient characteristics compared with the NIS cohort. CONCLUSIONS: Despite significant variability in patient characteristics and treatment methods among 2 sources of data analyzed, ERT in stroke patients not eligible for intravenous thrombolysis appears to be a relatively safe and effective treatment alternative that is being used increasingly nationwide.

Acute Disease↗

Spontaneous bilateral recanalization in bilateral internal carotid artery occlusion.

The authors report a young woman with bilateral internal carotid artery occlusion shown by carotid angiography. There was spontaneous bilateral recanalization demonstrated radiographically. The possible causes, e.g. the intake of oral contraceptive drugs, a spontaneous intimal dissection and other etiological features are discussed and the literature is reviewed.

Adult↗

Endothelial functions in pathophysiology of thrombosis and fibrinolysis: late spontaneous recanalization of an occluded internal carotid artery--a case report.

The use of oral contraceptives is a potential cause of ischemic stroke in young women. The risk of stroke is higher when contraceptives contain high levels of estrogens. A thrombotic occlusion of the right internal carotid artery, seen on ultrasound, developed in a patient who was taking high-dose estrogen contraception. Recanalization occurred several months later by spontaneous thrombolysis and was confirmed by cerebral angiography. This case suggests that the activation of endothelial spontaneous antithrombotic mechanisms may allow the dissolution of a thrombus, once the cause of the thrombosis has been identified and removed and when the endothelium has maintained its functional integrity.

Adult↗

Depletion of circulating alpha(2)-antiplasmin by intravenous plasmin or immunoneutralization reduces focal cerebral ischemic injury in the absence of arterial recanalization.

In the absence of arterial recanalization, thrombolytic agents induce a dose-related extension of focal cerebral ischemic injury (FII) in experimental animals. However, FII is smaller in mice lacking alpha(2)-antiplasmin (alpha(2)-AP), the physiologic inhibitor of plasmin, suggesting its depletion might reduce FII in the absence of reperfusion. Therefore, the effect of human plasmin (Pli), human miniplasmin (mPli), and an Fab fragment neutralizing murine alpha(2)-AP (Fab-4H9) on FII after middle cerebral artery (MCA) ligation was studied in mice and in hamsters. In BALB/c mice, the median FII after 24 hours was 28 microL (range, 20-34) (n = 10) with saline and 23 microL (range, 17-26) (n = 9) with a single bolus of 0.07 mg Pli, given after MCA ligation (P =.010), which reduced alpha(2)-AP to 44% and fibrinogen from 0.75 to 0.44 g/L. FII was 20 microL (range, 13-26) (n = 6, P =.025) with 0.2 mg mPli and was 24 microL (range, 20-27) (n = 6, P =.020) with 1.7 mg Fab-4H9. Neuronal atrophy and reduction of laminin immunoreactivity were comparably observed in the infarct area after saline and Pli. In hamsters, a single bolus injection of 1 mg Pli, after MCA ligation, depleted alpha(2)-AP and fibrinogen and reduced FII at 24 hours from 20 microL (range, 9.9-38) (n = 6) to 7.0 microL (range, 0.44-31) (n = 7, P =.032). Thus, reduction of circulating alpha(2)-AP, with a single bolus of plasmin or of a neutralizing antibody fragment, significantly reduced FII after MCA ligation in mouse and hamster models, suggesting that, provided these observations can be extrapolated to human beings, transient depletion of circulating alpha(2)-AP might reduce ischemic stroke in the absence of reperfusion.

Animals↗

Streptokinase in acute stroke: effect on reperfusion and recanalization. Australian Streptokinase Trial Study Group.

The Australian Streptokinase Trial was a randomized, double-blind, placebo-controlled trial, in which streptokinase (SK, 1.5 million IU I.V.) was given within 4 hours of stroke onset. In a subset of 37 patients, 99mTc-labeled D,L-hexamethylpropylene amine oxime single-photon emission computed tomography (SPECT) and/or transcranial Doppler (TCD) studies were performed before and after therapy to test the hypothesis that SK may improve the hemodynamic measures of reperfusion/recanalization rates (TCD parameter) within 24 hours. Eighteen patients received SK and 19 placebo. Baseline characteristics were similar in both groups, and there were no differences in clinical outcomes assessed at 3 months after stroke. Although there was no increase in the group mean perfusion defect or volume on SPECT after thrombolytic therapy, a larger number of patients demonstrating the combined end point of reperfusion or recanalization was seen in the SK group (13/14, 93%) than in the placebo group (7/14, 50%; p = 0.01). Although SK given within 4 hours of acute ischemic stroke appears to improve arterial patency/tissue reperfusion, this effect is neither early nor extensive enough to influence overall clinical outcome.

Acute Disease↗

Recanalization of long-lasting middle cerebral artery occlusion by a combination of surgical and interventional approaches: technical case report.

OBJECTIVE AND IMPORTANCE: In strictly selected cases of middle cerebral artery (MCA) occlusion, revascularization by extracranial-intracranial (EC-IC) bypass can be considered. The interventional recanalization of the occlusion under direct surgical control has not been reported in the literature so far. CLINICAL PRESENTATION: A 39-year-old Caucasian female patient had experienced an ischemic stroke 15 years before she came to our attention. At that time, occlusion of the right MCA was diagnosed by angiography. Her neurological deficit resolved within 6 months. Fifteen years later, the patient experienced repeated numbness of her left-sided extremities, which was refractory to medical treatment. Angiography revealed an occluded M1 segment of the MCA. Perfusion computed tomography without and after CO2 stimulation disclosed impaired cerebrovascular capacity. INTERVENTION: The patient was scheduled for EC-IC bypass. The MCA tree was exposed, and the occluded portion was found to be 10 mm long. We then decided to reopen the vessel by balloon dilation under direct visual control. A catheter was advanced to the M1 origin, where a glidewire was passed into the vessel lumen. With only a little help from the surgeon, it was surprisingly easy to direct the glidewire through the occluded segment. At this time, flow through the M1 segment was re-established. Flow through the MCA that had occluded for 15 years was re-established. CONCLUSION: On the basis of our experience, in nonatherosclerotic occlusions, intravascular intervention may be considered.

Adult↗

Acute myocardial infarction in a patient with essential thrombocythemia: successful treatment with percutaneous transluminal coronary recanalization.

A 65-year-old woman with essential thrombocythemia (ET) was admitted to hospital where she was diagnosed as acute myocardial infarction (AMI). Because of abundant thrombus of right coronary arteries, percutaneous transluminal coronary recanalization by administration of urokinase was selected as the reperfusion therapy, resulting in successful revascularization with Thrombolysis in Myocardial Infarction grade III coronary flow. The maximum creatine kinase reached 507 IU/L, and left ventriculography performed at 1 month after initiation of both anticoagulant and antiplatelet therapies revealed reduced motion in the inferior wall with an ejection fraction of 57%. Despite good recovery of left ventricular function, bleeding complications, such as epistaxis or ecchymoma, which did not require blood transfusion, occurred during the clinical course. Because ET causes not only thrombus formation but also bleeding tendency, it is very important to carefully follow-up any clotting abnormality in AMI patients with ET.

Aged↗

Our experience of coronary intervention. Intracoronary guide wire recanalization and percutaneous transluminal coronary angioplasty.

Our old and new trials of coronary intervention therapy are introduced and analyzed. A method using intracoronary guide wire recanalization (Endo's method) is introduced. Two unusual cases of percutaneous transluminal coronary angioplasty (PTCA) from our initial experience of 18 cases are also presented. One is a 60-year-old patient who had transient complete right bundle branch block in a post-PTCA treadmill test. The other is a 45-year-old patient with unstable angina who developed myocardial infarction right after the PTCA but in whom post-PTCA coronary arteriography showed no apparent stenosis at the site of the PTCA.

Angioplasty, Balloon↗

Increased coronary vasomotor tone in acute myocardial infarction patients with spontaneous coronary recanalization.

To clarify the role of coronary spasm or dynamic coronary obstruction in the development of acute myocardial infarction (AMI) with spontaneous recanalization (SR), symptoms in 296 patients with AMI admitted within 24 h after the onset of chest pain were analyzed just before and after onset, and coronary angiograms were analyzed soon after onset. Patients were divided into 3 groups according to the initial angiographic findings in the infarct-related coronary artery (IRCA): group 1 comprised 172 patients with total occlusion (TIMI O); group 2 comprised 57 patients with subtotal occlusion (TIMI 1,2); and group 3 comprised 67 patients with SR (TIMI 3). The incidence of SR was 20.3% at 0-4 h after onset, 22.2% at 4-6 h, 19.7% at 6-12 h, 24.0% at 12-24 h, and 36.0% at 24 h or later. The incidence of SR did not increase significantly as time elapsed. The incidence of angina at rest and variable-threshold angina before the onset of infarction was only 16.2% in group 1, but was significantly higher in groups 2 (64.3%) and 3 (61.9%). The incidence of intermittent chest pain at onset in group 1 (8.4%) was significantly lower than in groups 2 (54.5%) and 3 (38.8%). Vasodilation of the proximal normal segment adjacent to the stenotic site of the IRCA induced by intracoronary nitroglycerin was significantly higher in groups 2 (11.7 +/- 1.2%) and 3 (20.7 +/- 2.6%) than in group 1 (4.0 +/- 0.6%). These results suggest that coronary spasm or dynamic obstruction may be involved in the pathogenesis of thrombus formation or coronary obstruction causing AMI in many Japanese patients.

Adult↗

Recanalization of an occluded major side branch after stenting with intracoronary adenosine.

Adenosine is a powerful direct coronary vasodilator with a very short half-life that has been shown to be effective in avoiding and reversing no reflow. We report an immediate successful recanalization of an occluded major side branch after stenting with acute intracoronary adenosine administration. The beneficial effect of adenosine may imply that the side branch occlusion (SBO) in this case could be due to spasm or distal embolization of the atherosclerotic debris ending up with no flow. We believe that adenosine could be helpful in at least some cases of SBO and therefore may be worth attempting.

Adenosine↗

Is there recanalization of the great saphenous vein 2 years after endovenous laser treatment?

PURPOSE: To report the 2-year single-center results of endovenous laser treatment (EVLT) for reflux in the great saphenous vein (GSV). METHODS: From January 2002 to January 2003, 85 symptomatic patients (56 women; mean age 49 years, range 27-80) underwent EVLT in 100 limbs. All patients were symptomatic, and the majority (67, 79%) had CEAP clinical class C2 venous disease. After treatment, they were monitored by clinical evaluation and duplex imaging. RESULTS: The initial treatment was completed in 93 limbs. Complications consisted of bruising (31%), tightness (17%), pain (14%), induration (2%), and superficial thrombophlebitis (2%). No severe complications were observed. Over a mean follow-up of 29 months (range 24-37), 3 patients died and 14 were lost to follow-up, leaving 88 (95%) and 76 (82%) limbs available for imaging surveillance at 1 and 2 years, respectively. At 3 months, treatment was anatomically successful in 84% of cases (78 complete occlusion, 7 partial occlusion, and 8 nonocclusion) and functionally successful in 89% (83 no reflux, 10 reflux). All technical failures and 73% (n=11) of the treatment failures occurred in the first half of the studied population, indicating a learning curve effect (p=0.015). Mean energy delivered per unit length was 39+/-8 J/cm (range 25-65) for successful treatment (n=78) and 30+/-10 J/cm (range 21-50) for failed treatment (n=15). No recanalization or recurrent GSV reflux after anatomically and functionally successful treatment was observed in 73 and 61 limbs at 1 and 2-year follow-up, respectively. CONCLUSIONS: EVLT is a feasible, safe, and fast procedure for eliminating GSV reflux and has excellent cosmetic results. Despite the learning curve, we believe that the treatment results are promising. When successful treatment is achieved by EVLT, a prospective follow-up of 2 years demonstrates durable results.

Adult↗

Subintimal recanalization of the femoropopliteal segment to promote healing of an ulcerated below-knee amputation stump.

PURPOSE: To describe the use of the subintimal technique to revascularize an ulcerated below-knee amputation stump. CASE REPORT: A 64-year-old man with persistent ulceration of a below-knee amputation stump underwent attempted percutaneous revascularization. Via antegrade puncture, the femoropopliteal occlusion was recanalized subintimally and eventually opened into a large medial geniculate collateral branch, improving the stump flow. The procedure was uneventful, and at 6 months, the patient was pain-free and able to mobilize with his prosthetic limb. CONCLUSION: Subintimal revascularization of a critically-ischemic below-knee amputation stump may be a useful option and should be considered in clinical situations like this.

Amputation, Surgical↗

Techniques for endovascular recanalization of supra-aortic trunks.

The supra-aortic are no stranger to endovascular interventions. Since the 1980s, interventionists have been evaluating and refining the use of transluminal techniques for recanalizing stenotic and occlusive lesions in these large-bore, high-flow vessels. The authors present their methodologies for evaluating, selecting, and treating supra-aortic lesions with balloon angioplasty and stenting. Helpful suggestions are offered for optimizing the outcome of these endovascular approaches to atherosclerotic occlusive disease in the supra-aortic trunks.

Angioplasty, Balloon↗

Recanalization 24 months after endovascular repair of a large internal iliac artery aneurysm with use of stent-graft.

An 83-year-old man with a large internal iliac artery aneurysm (IIAA) was treated with the use of stent-graft, suggesting successful results at 3, 6, and 12 months after treatment. However, 24-month follow-up computed tomography showed minor peripheral opacification of the IIAA. The patient underwent surgical endoaneurysmorrhaphy. No previous report of long-term recanalization of a satisfactorily thrombosed iliac artery aneurysm at 2 years or more after stent-grafting has been previously reported. Further follow-up studies need to be performed on the present procedure before anyone can confidently recommend it in regard to its long-term safety.

Aged↗