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[An experimental study of excimer laser angioplasty].

An excimer laser, which is a pulsed ultraviolet laser and ablates tissue precisely with no thermal injury, is expected to coronary laser angioplasty. We transmitted XeCl excimer laser (308 nm) via a 400 microns fused silica fiber. In the first experiment, we studied about excimer laser ablative effects to normal canine arteries and atherosclerotic rabbit aortas, and about healing responses following excimer laser irradiation in both models. Surfaces after excimer laser ablation were slightly rough but no thermal injury was found in the media. And for healing process of normal canine arteries, endothelial cells appeared at 3 weeks and completely covered surfaces with fibrointimal ingrowth at 3 months. In the rabbit aortas, at 3 weeks there was reconstruction of the surface. At 2 months no accelerated atherosclerotic or aneurysmal changes were observed. In the second, with this excimer laser (short pulse) and 400 microns fused silica fibers (distal fiber-end power: 3-6 mJ/pulse), we performed transluminal laser angioplasty to recanalize totally occluded canine femoral arteries under an angioscopic guidance. We cold recanalize 8 of 9 totally occluded arteries with no thermal injury of adjacent tissue, though perforations were observed in 7 of 9 arteries. In the third, we used a newly-developed long pulse excimer laser, with which distal fiber-end energy was about 3 to 4 times as much as the short pulse one, to recanalize totally occluded canine arteries. In result, recanalization was performed in 6 of 8 arteries rapidly with little thermal injury. However, we observed perforations in 6 of 8 arteries like the short pulse one. Multifiber catheter ("over the wire system") coupled with this long-pulse excimer laser was used to reconstruct stenotic iliac arteries of atherosclerotic rabbit models. The procedure was successful in all the 5 rabbits. In conclusion, our preliminary results suggested that further developments of a more powerful and longer pulse-duration excimer laser, optic delivery system and guidance system would make excimer laser angioplasty safer and more effective method in the near future.

Angioplasty, Laser↗

Reversible MR imaging abnormalities following cerebral venous thrombosis.

BACKGROUND AND PURPOSE: Although rare, cerebral venous thrombosis (CVT) is being diagnosed more frequently owing to improved imaging techniques. The venous infarcts caused by CVT in 50% of patients are largely reversible and differ from arterial stroke. Our purpose was to study the time-dependent changes of venous infarcts on MR images and to define the variables that influence lesion volume in humans. METHODS: MR images and venous angiograms were evaluated in 15 consecutive patients with venous infarcts due to CVT of sinus, cortical, or internal veins. All patients were treated with intravenous dose-adjusted heparin followed by oral anticoagulation for 12 months. Reduction of signal intensity changes on T1- and T2-weighted images was correlated to the degree of recanalization, age, initial absolute lesion size, and hemorrhage. RESULTS: Within the first 30 days, we found a significant correlation between the volume of the lesion on T1-weighted images and recanalization. However, early recanalization did not influence the final lesion volume after 12 months. Eleven patients showed complete resolution of changes on T1- and T2-weighted images. Age of the patients influenced initial absolute volume of brain damage. CONCLUSION: In venous stroke, even large parenchymal changes can resolve completely independent from recanalization of the thrombosed veins and sinuses. A plausible hypothesis is that venous infarcts largely consist of a persistent edema and that the lesion volume is influenced by the development of collateral veins. However, further investigations are necessary to understand the underlying abnormal mechanisms.

Administration, Oral↗

Diagnostic and prognostic value of early MR Imaging vessel signs in hyperacute stroke patients imaged <3 hours and treated with recombinant tissue plasminogen activator.

BACKGROUND AND PURPOSE: Analogous to the CT hyperattenuated vessel sign (HMCAS), MR imaging may show hypo- or hyperintense vessels in acute ischemic stroke (AIS) patients. We assessed the diagnostic and prognostic strength of early MR imaging vessel signs in AIS patients treated with intravenous thrombolysis (IVT) within 3 hours of the onset of symptoms. METHODS: We studied AIS patients both treated with IVT and stroke MR imaged within 3 hours of the onset of symptoms and at 2 hours and 24 hours after treatment. We assessed the presence or absence of early vessel signs (hyperintense fluid-attenuated inversion recovery sign [FLAIR HVS]; gradient-echo susceptibility vessel sign [GRE SVS]) compared with a combined MR angiography/perfusion-weighted imaging reference and their strength for predicting clinical outcome (favorable vs. poor, independent vs. dependent, or dead, death), recanalization (by clot composition and flow), and hemorrhage in uni- and multivariate analysis. RESULTS: Fifty-six patients (age range, 76 years +/- 13 years; median National Institutes of Health stroke scale score [NIHSSS], 11) met the inclusion criteria. Forty-four patients (78.6%) had a vessel occlusion at baseline; 22 of them (50%) recanalized. Nineteen patients (33.9%) suffered some form of intracranial hemorrhage (ICH), 24 patients (42.9%) had an independent outcome, 18 patients (32.1%) a favorable outcome, and 14 patients died. Compared with our combined reference for vessel status PWI/MRA, the sensitivities of CT HMCAS, FLAIR HVS, and GRE SVS were 40%, 66%, and 34%, respectively, and improved during the hours that followed. Localization was accurately reflected by FLAIR HVS but not by GRE SVS. Only NIHSSS and age were independent predictors for recanalization and all clinical outcomes in multiple logistic regression analysis. CONCLUSION: Although early vessel signs can be helpful in the diagnosis of intravascular disease, they do not independently predict recanalization, ICH, or any of the three clinical outcomes in a multivariate logistic regression model. Thrombus composition as reflected by signal intensity characteristics on GRE and FLAIR does not predict the therapeutic effect of IVT.

Aged↗

Selective endovascular treatment of intracranial aneurysms with a liquid embolic: a single-center experience in 39 patients with 41 aneurysms.

BACKGROUND AND PURPOSE: Although embolization with detachable coils is an accepted alternative to surgical clipping, a major long-term problem is aneurysm recanalization due to coil compaction. Liquid embolic agents are a possible alternative as filling material that might decrease the recanalization rate. We evaluated the use of a liquid embolic for endovascular treatment of intracranial aneurysms. METHODS: During 1999-2003, 10 patients with 11 small aneurysms (group 1) and 29 patients with 30 large or giant aneurysms (group 2) were treated with a liquid embolic. Of 32 female and seven male patients, 20 had mass effect and two had subarachnoid hemorrhage; 17 were asymptomatic. All aneurysms were judged unsuitable for regular treatment; selective embolization was performed with a liquid embolic alone or with coils and liquid embolic. Stent placement was performed in 15 cases. Clinical and anatomic outcomes were assessed with the Modified Glasgow Outcome Scale and with angiography at 3, 12, and 24 months. RESULTS: In group 1, good or excellent outcome and complete occlusion were observed in all patients. In group 2, clinical outcome was good or excellent in 26 patients and fair in one, and death occurred in two patients (one procedure related and one disease related). Technical complications occurred in four patients in group 1 (one permanent neurologic deficit) and in four patients in group 2 (one patient died, two remain hemiparetic, one remains asymptomatic). Follow-up images showed two recanalizations in group 1 and nine in group 2. CONCLUSION: Selective embolization with a liquid embolic is useful to treat aneurysms unsuitable for coiling or for patients in whom previous treatment failed. This mostly applies to large and giant aneurysms in which morbidity and mortality rates are better than those associated with surgery, and the recanalization rate is lower than that previously described with coiling.

Adult↗

N-butyl 2-cyanoacrylate embolization of spinal dural arteriovenous fistulae: CT evaluation, technical features, and outcome prognosis in 26 cases.

BACKGROUND AND PURPOSE: This study investigated the role of CT as an early predictor of outcome prognosis after glue embolization of spinal dural arteriovenous fistulas (SDAVF). METHODS: Over a 13-year period, 26 patients underwent glue embolization of SDAVF and were retrospectively reviewed. Immediately after embolization, each patient had CT evaluation of cast position. Mean follow-up angiography was 23.4 months (range, 1-87 months; median, 21 months). Both MR images and clinical data (e.g., gait and micturition disabilities according to the Aminoff and Logue disability scale, deep and superficial sensitivity) were analyzed, with a mean follow-up of 37.7 months (range, 12-98 months; median, 28 months). Data were tested by univariate analysis by using Fisher's exact test and the Kruskall Wallis test, depending on the order of the qualitative variables. RESULTS: Glue was found in the dura mater on CT in 19 (73%) patients. None of these patients had a recanalized fistula on angiography, and the clinical status of all of them improved. Glue was observed in or proximal to the foramen on CT in seven (27%) patients. In five of them, the fistula was recanalized within a mean period of 9 months (range, 3-24 months; median, 6 months) and their clinical status worsened. All five required surgical treatment. On angiography, the absence of fistula recanalization was observed in 21 (81%) patients and correlated with improvements in gait (P = .016), sensitivity (P = .030), and micturition (P = .080). It also correlated with a decrease in the extent of the abnormally high intramedullary T2 signal intensity (P = .002), a decrease in spinal cord diameter (P = .017), and the resolution of prominent perimedullary vessels (P < .001). The presence of glue within the dura mater on CT correlated with the absence of fistula recanalization (P = .045) and with overall improvement in clinical status, including gait and/or sensitivity and/or micturition (P = .042). CONCLUSION: CT evaluation of embolization cast position immediately after embolization may constitute an early and reliable tool for predicting permanent fistula occlusion and the prognosis for outcome.

Adult↗

Endovascular treatment of posterior circulation cerebral aneurysms by using Guglielmi detachable coils: a 10-year single-center experience with special regard to technical development.

BACKGROUND AND PURPOSE: The purpose of this study was to analyze the immediate and long-term angiographic and clinical results of endovascular treatment of posterior circulation aneurysms with special regard to technical development. MATERIALS: Between 1993 and 2003, 46 patients with 47 aneurysms of the posterior circulation were referred to our institution for endovascular treatment. Mean angiographic follow-up was 1.7 years. Clinical follow-up was determined at hospital discharge and by using a questionnaire for long-term follow-up (mean, 3.3 years). To analyze technical development, patients treated before (group 1) and after (group 2) implementation of 3D Guglielmi detachable coils (3D GDCs) in 1999 were compared. Multivariate analysis was performed to determine factors predictive of clinical and technical outcome. RESULTS: Overall, at initial treatment complete occlusion was achieved in 27 (57.4%) aneurysms, a neck remnant was present in 16 (34.0%) aneurysms, incomplete occlusion was achieved in 3 (6.4%) aneurysms, and in 1 (2.1%) case occlusion was not attempted. Procedure-related permanent morbidity was 4.3%, and the mortality rate was 0%. There was no rebleeding of treated aneurysms. Complete occlusion at initial treatment (P = .003) and recanalization rate (P = .008) correlated with aneurysm sac size. A statistically significant relationship between Hunt and Hess/World Federation of Neurologic Surgeons clinical grading scale score and clinical outcome (Glasgow Outcome Score) was found (P < .05). Subgroup analysis revealed that a higher initial obliteration rate of larger aneurysms was achieved in group 2 (3D GDC, 22 patients, 22 aneurysms) than in group 1 (23 patients, 24 aneurysms; P = .03). At angiographic follow-up, overall recanalization was 47.1% in group 2 and 47.6% in group 1. Aneurysm neck size was not found to be correlated with occlusion and recanalization rate. CONCLUSION: In our series, GDC technology was an effective and safe technique for the treatment of posterior circulation aneurysms. Aneurysm sac size was predictive for occlusion rate and the Hunt and Hess/World Federation of Neurologic Surgeons grade for clinical outcome. The introduction of 3D GDCs into our practice significantly improved the initial occlusion rate but did not affect the incidence of recanalization.

Adolescent↗

Safety of mechanical thrombectomy and intravenous tissue plasminogen activator in acute ischemic stroke. Results of the multi Mechanical Embolus Removal in Cerebral Ischemia (MERCI) trial, part I.

BACKGROUND: The MERCI (Mechanical Embolus Removal in Cerebral Ischemia) trial reported efficacy of the Merci Retriever for opening intracranial vessels in patients ineligible for intravenous (IV) tissue plasminogen activator (tPA). Patients who receive IV tPA but do not recanalize may also benefit from thrombectomy, but the revascularization efficacy and safety of this strategy has not been reported. METHODS: Multi MERCI is an ongoing international, multicenter, prospective, single-arm trial of patients with large vessel stroke treated within 8 hours of symptom onset. Patients were enrolled who had received IV tPA but did not recanalize or who were ineligible for IV tPA. Primary outcome was vascular recanalization (Thrombolysis in Myocardial Infarction [TIMI] score II/III) and safety. RESULTS: One hundred eleven patients received the thrombectomy procedure. Mean age +/- SD was 66.2 +/- 17.0 years, and baseline National Institutes of Health Stroke Scale (NIHSS) score was 19 +/- 6.3. Thirty patients (27%) received IV tPA before intervention. Treatment with the Retriever alone resulted in successful recanalization in 60 of 111 (54%) treatable vessels and in 77 of 111 (69%) after adjunctive therapy (IA tPA, mechanical). Symptomatic intracranial hemorrhage (ICH) occurred in 10 of 111 (9.0%). Clinically significant procedural complications occurred in 5 of 111 (4.5%) patients. The symptomatic ICH rate was 2 of 30 (6.7%) in patients pretreated with IV tPA and 8 of 81 (9.9%) in those without (P > .99). CONCLUSIONS: Mechanical thrombectomy after IV tPA seems as safe as mechanical thrombectomy alone. Mechanical thrombectomy with both first- and second-generation Merci devices is efficacious in opening intracranial vessels during acute ischemic stroke in patients who are either ineligible for IV fibrinolytic therapy or have failed IV fibrinolytic therapy.

Aged↗

[ApoE genotype influences on efficacy and safety of thrombolytic treatment for ischemic stroke].

INTRODUCTION: Apolipoprotein E has been associated with intracerebral hemorrhages and with neurological outcome of ischemic stroke patients treated with rt-PA. Therefore, we hypothesized that ApoE genotype might influence the appearance of post-tPA hemorrhagic transformation and that the favorable outcome of E2 patients might be due to better rates of recanalization. PATIENTS AND METHODS: We analyzed the ApoE genotype of 77 patients with ischemic stroke involving the territory of the middle cerebral artery who received rt- PA within 3 h of symptoms onset. The hemorrhagic events were evaluated by computed tomography and the arterial recanalization by transcraneal doppler. RESULTS: We did not observe any association between ApoE genotypes and the rates of hemorrhagic transformation following rt-PA treatment (E2 = 33.3 %, E3 = 32.7%, E4=11.8%; p=0.241). Rates of artery recanalization following thrombolysis were similar regarding ApoE genotypes at 1 hour post-tPA administration (E2=40%, E3+E4=45.9%; p=0.799), at 6 hours post-tPA (E2=80%, E3+E4=62.3 %; p=0.43) or at 24 hours post-tPA (E2= 100%, E3+E4=75%, p=0.203). No association was observed between ApoE genotypes and NIHSS scores at 48 hours (E2=8, E3+E4=12; p=0.811) nor with the modified ranking scale at 3 months (E2=1.5, E3+E4=4; p=0.350). CONCLUSIONS: In our group of stroke patients, ApoE genotypes are not related with the presence of hemorrhagic transformations neither with the rates of recanalization following thrombolytic treatment.

Aged↗

Clot removal therapy by aspiration and extraction for acute embolic carotid occlusion.

BACKGROUND AND PURPOSE: The purpose of our retrospective study was to investigate the feasibility, safety, and efficacy of clot removal therapy by aspiration and extraction for patients with acute stroke with embolic internal carotid artery (ICA) occlusion. METHODS: Of 814 consecutive patients with acute ischemic stroke admitted to our institution from March 2003 to April 2005, clot removal therapy was performed for 14. Inclusion criteria were patients (1) presenting within 6 hours of onset of cardioembolic stroke, (2) with serious neurologic symptoms defined by a National Institutes of Health Stroke Scale (NIHSS) score of at least 11, (3) without extensive high signal intensity on diffusion-weighted MR images but with decreased ipsilateral hemispheric cerebral blood flow on perfusion-weighted images (perfusion/diffusion mismatch), and (4) with total ICA occlusion on angiograms. We removed clots by aspiration and extraction with a microsnare through either a guiding or balloon guide catheter. Radiographic results, 7-day NIHSS, 3-month modified Rankin Scale, and procedure-related complications were evaluated. RESULTS: Of 10 patients treated with the balloon guide catheter to temporarily interrupt proximal flow, 7 obtained complete or partial recanalization. The 4 patients treated with the guiding catheter had no recanalization. Of the 7 patients with recanalization, 6 had favorable 7-day neurologic and 3-month functional outcome; all showed anatomic crossflow via the anterior communicating artery. A procedure-related complication, distal embolization into the ipsilateral anterior cerebral artery, occurred in 1 patient. CONCLUSION: Balloon guide catheter-assisted clot removal therapy for embolic ICA occlusion may provide a high recanalization rate and good clinical outcome in patients with anatomic crossflow.

Adult↗

Laser arterial disobstructive procedures in 148 lower extremities.

Preoperative arteriographic findings in immediate postoperative results as well as follow-up studies of treatment with argon and YAG lasers have been evaluated in 148 lesion found in 137 patients. Preoperative arteriography revealed a solitary lesion in 42 of 148 legs (28%) examined, and a combined lesion was found in the remaining 106 legs (72%). Incapacitating intermittent claudication, rest pain, tissue loss, or a combination of these was an indication for laser arterial reconstruction. None of the argon laser-treated lesions was treated with balloon dilatation, but since March 1988 all appropriate YAG laser-treated lesions were immediately followed by laser-assisted balloon angioplasty. The lesions in 64 of 89 legs (72%) treated by argon and 42 of 59 (71%) treated by YAG were successfully recanalized. However, successful angioplasty was performed in 44 of 89 (49%) and 34 of 59 (58%) lesions, respectively. The recanalization depended on the type of lesion (tight stenosis vs occlusion) and the length of lesion (localized vs total-length occlusion). However, the success rate of recanalization was almost the same as the success rate when both laser systems were used. Argon laser treatment proved successful in 19 of 20 (95%) segmental occlusions in popliteal arteries, whereas YAG laser treatment proved successful in four of five (80%) short segmental (less than 15 cm) occlusions of superficial femoral arteries and in 16 of 23 (70%) long segmental (greater than or equal to 15 cm) occlusions of superficial femoral arteries. In 26 of 36 (72%) total-length occlusions of superficial femoral and popliteal arteries, recanalization was not possible (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Evaluation and management of post-thrombotic syndrome].

The number of patients with postthrombotic syndrome subsequent to venous thrombosis is continuously increasing. The risk of venous thrombosis is increased by the increasing age of the population, through increasingly-extensive surgical intervention, through hormonal contraception and through prolonged airline flights and the risk appears diminished by modern thrombosis prophylaxis. The course of the disease can be divided into an acute phase of thrombosis with a duration of about one week, the subacute phase lasting from the second to the fourth week and the phase of the postthrombotic syndrome. Pathophysiology Thrombotic occlusion can be compensated for by recanalization and collateralization. Concomitant with the generation of the blood clot, fibrinolytic factors are activated which can serve to lyse the thrombus. After organization of the remaining clot, blood flow can be re-established. The extent of recanalization can be quantified radiologically. In 35.5% of the patients there is complete recanalization, in 53.4% partial and in 11.1% no recanalization. At nearly all sites of venous occlusion preformed collaterals can be found. A hemodynamically meaningful occlusion causes an increase in the peripheral venous pressure. On use of Doppler ultrasound examination, there is absence of respiratory modulation as well as a high-frequency continuous signal which disappears as soon as collateral function is optimal. As the venous circulation adapts, there is dilatation in the collateral vessels, initially with preserved coaptation of the valve leaflets. This stage is designated as compensatory phlebectasia; phlebography of the great saphenous vein shows the typical findings. If the venous valves are incompetent, under some conditions the direction of flow may be reversed. An example of secondary varicosities in the region of the great and lesser saphenous vein is shown in Figure 3. The most frequent causes of valve damage are over-extension of the valve ring through recoil pressure and volume waves during standing, coughing and pressing in addition to local thrombus formation and inflammatory processes. In association with thrombosis in the femoropopliteal region with compensatory phlebectasia of the great saphenous vein, respiratory modulation in this vein can be detected with Doppler ultrasound examination. With secondary varicosities, which have to be differentiated from compensatory phlebectasia, on use of the Valsalva test or calf compression test there is pathologic, persistent retrograde blood flow, the calf compression test shows diminished A-sounds. In contrast to primary varicosities, with secondary varicosities of the great saphenous vein the distal dilatation is more marked than that seen proximally. Retrograde blood flow can extend to the foot with no obstacles.(ABSTRACT TRUNCATED AT 400 WORDS)

Dissection↗

[Outcome of coronary transluminal angioplasties followed by an occlusion].

Coronary occlusion is the most serious complication of percutaneous transluminal angioplasty. In 440 cases coronary occlusion occurred in 22 patients (5%). Treatment was coronary bypass in 12 cases mechanical recanalization in 7 cases and coronary bypass after unsuccessful mechanical recanalization in 3 cases. One patient died after mechanical recanalization and 9 (41%) had myocardial infarction confirmed by electrocardiography and angiography. The number of coronary occlusions increased initially but decreased with improvements in materials and techniques. It is concluded that coronary occlusion is a severe but rare complication of percutaneous angioplasty. Mechanical recanalization should be attempted, and in case of failure the patient should be referred for surgery. In the large majority of cases the outcome is benign.

Aged↗

[Coronary thrombolytic therapy in acute myocardial infarction: time dependence of beneficial effects assessed by two-dimensional echocardiography].

To elucidate the effects of coronary thrombolytic therapy in acute myocardial infarction, we observed serially the degree of left ventricular (LV) wall motion immediately after on day 1, and on days 7, 14, 21 and 28 after thrombolytic therapy, in 22 patients with acute anteroseptal myocardial infarction. Base-line coronary arteriography revealed significant lesions in the proximal portions of the left anterior descending artery of all the patients. The patients were categorized according to results of thrombolytic therapy as Group I-a: seven patients with spontaneous or successful recanalization within three hours of onset of chest pain; Group I-b: nine patients with successful recanalization between three and seven hours, with a mean of 4.8 hours from onset; and Group II: six patients in whom thrombolytic therapy was unsuccessful and infarct-related vessels remained totally occluded. The LV wall motion index (WMI) was defined as the sum of point scores for the degrees of regional wall motion at nine segments on serial two-dimensional echocardiograms, and used for quantitative assessments of LV function. Results were as follows: On day 1, immediately after thrombolytic therapy, the WMI of Group I-a was smaller than that of Group II. However, there was no significant difference between Groups I-a and I-b and between Groups I-b and II. These findings suggest that LV function cannot be recovered immediately after recanalization of occluded arteries unless recanalization occurs exceptionally early. Percent improvement of the WMI from days 1 to 28 in Group I-a, 65 +/- 14%, was significantly greater than that in Group I-b, 31 +/- 18%. However, Group II did not show significant improvement in the WMI. The WMI in Group I-a decreased significantly from days 1 to 7 (9.0 +/- 1.6 vs 7.1 +/- 1.8, p less than 0.05); whereas, the WMI in Group I-b showed no significant decrease until day 21. On day 1, the regional wall motion of the antero-apical wall was akinetic or dyskinetic in all patients studied. On day 28, it improved in six of seven patients in Group I-a, while it remained akinetic or dyskinetic in all patients in Groups I-b and II.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

[Intracoronary thrombolytic therapy of myocardial infarction].

The results of intracoronary thrombolytic therapy with avelysine given to 21 patients with acute myocardial infarction are described. Intracoronary thrombolysis was performed on the average 5 h and 30 min after myocardial infarction onset. Recanalization of the coronary artery was attained in 16 patients, with no lethal outcomes. One patient died out of the 5, in whom attempts to recanalize the artery ended in failure. Recanalization of the coronary arteries led to improvement of left ventricle function and appreciably accelerated the time-course of the enzymatic shifts (KPK and LDH) in blood of myocardial infarction patients. After successful recanalization of the coronary artery the disease in myocardial infarction patients took a far milder course as compared to those who did receive intracoronary thrombolytic therapy.

Adult↗

[Time-course changes in serum myosin light chain 1 concentration and clinical implication in patients with reperfused acute myocardial infarction].

The correlation between the time-course changes in the serum concentration of myosin light chain 1 (ML-1) and left ventricular (LV) function was investigated in 37 patients with initial anterior acute myocardial infarction (AMI) after successful reperfusion. All patients were confirmed to have coronary arteries recanalized to TIMI grade 3 within 6 hours of AMI and patent arteries about 2 weeks after recanalization. LV function was assessed by left ventriculography. The patients were divided into two groups according to the time-course changes in the serum concentration of ML-1; 20 who showed an early peak of the serum ML-1 level within 24 hours and a late peak 3 to 5 days after recanalization (bimodal pattern: group B), and 17 who showed a single peak of the serum ML-1 level after recanalization (unimodal pattern: group U). The sum of ST elevation in an electrocardiogram before reperfusion and the additional ST elevation during reperfusion were both greater in group B than in group U (p < 0.1 and p < 0.05, respectively). The peak serum concentration of creatine kinase was significantly greater in group B than group U. LV dilatation was more extensive and the improvement of LV function was poorer in group B compared to group U.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Pulmonary artery adventitial changes and venous involvement in primary pulmonary hypertension.

Primary pulmonary hypertension (PPH) is associated with a spectrum of structural changes in the pulmonary arteries: increased medial thickness, eccentric and concentric intimal thickening, obliteration and recanalization of arteries, and appearance of plexiform and dilatation lesions. The purpose of the present study was to further characterize these structural changes with particular emphasis on arterial adventitial thickness and alterations in the walls of the pulmonary veins. In addition, to determine whether the characteristic structural changes of PPH were size related, each was related to external diameter. With quantitative techniques, the pulmonary vasculature of 19 patients with PPH and 7 controls was examined by light microscopy. In all 19 patients, we found a striking increase in adventitial, as well as intimal and medial, thickness in arteries of all sizes when compared with controls (P < 0.05). In addition, we found intimal and adventitial thickening of pulmonary veins < 250 mu in diameter in approximately half of the PPH cases (P < 0.05). The frequency of arterial obliteration, concentric intimal thickening, and recanalization was 16, 18, and 11 of 19 cases, respectively. These changes were most prevalent in arteries less than 200 mu in diameter whereas eccentric intimal thickening and plexiform lesions occurred in 15 and 6 of the patients, respectively, and were most widespread in arteries > 200 mu. We conclude that remodeling of the pulmonary vasculature in PPH routinely includes thickening of the arterial adventitia and frequently also includes changes in the walls of the pulmonary veins. The finding that recanalization occurs predominantly in the smaller arteries whereas eccentric intimal thickening occurs mainly in the larger ones suggests that recanalization should not be considered a consequence of thromboemboli but may also occur at sites of more fibrotic intimal change.

Adolescent↗

[Calcitonin gene-related peptide and thrombolysis].

After thrombolytic therapy with urokinase (UK) plasmaimmunoreactive calcitonin gene-related peptide (CGRP-ir) in patients with acute myocardial infarction (AMI) was increased rapidly, and 2 hours after treatment with UK the plasma CGRP-ir reached peak value which was 5 times higher than that before thrombolytic therapy. Fourteen hours after therapy with UK the plasma CGRP-ir gradually decreased to the initial level before treatment. In rat model with abdominal aorta thrombosis induced by FeCl3-injured vascular endothelium, it was found that change in plasma CGRP-ir of the rats after treatment with UK was similar to that of AMI patients, and that administration of CGRP alone had no recanalization effect on the thrombotic blood vessel. However, treatment with CGRP synergically potentiated the UK-induced vascular recanalization in a dose-dependent manner. And antagonist of CGRP (CGRP8-37) significantly attenuated the recanalization action of UK. The results suggest that release of CGRP by tissues could play an endogenous protective role in thrombolytic therapy with UK, and exogenous administration of CGRP might be useful clinically as an assistant of vascular recanalization.

Animals↗

Thrombolytic therapy in acute occlusion of the intracranial internal carotid artery bifurcation.

PURPOSE: To evaluate efficacy and clinical benefit of early thrombolytic therapy in intracranial internal carotid artery occlusion. METHODS: Thirty-two patients (mean age, 56 years) with acute intracranial internal carotid artery occlusion were studied clinically and with CT and angiography before and after thrombolytic therapy with intravenous alteplase (n = 16), superselective intraarterial alteplase (n = 8), and superselective intraarterial urokinase (n = 8). RESULTS: Initial CT showed a large parenchymal hypodensity in 11 (34%) patients, a small hypodensity in 15 (47%) patients, and no hypodensity in 6 (19%) patients. Recanalization after thrombolytic therapy was observed in 4 patients (12.5% in each treatment group). Follow-up CT showed six hemorrhagic infarcts and four parenchymal hematomas unrelated to recanalization, alteplase, or urokinase administration, but commonly associated with intraarterial treatment. Clinical outcome was fatal in 53%, poor in 31%, and moderate or good in 16% of the patients. Outcome was equal in different treatment groups and closely linked to both the quality of leptomeningeal collaterals and the extent of parenchymal hypodensity on the first CT. CONCLUSION: Because intravenous or intraarterial treatment with alteplase or urokinase fails to recanalize the vascular obstruction, it does not improve the prognosis of intracranial internal carotid artery occlusion over that of the natural course. Improved results may be possible with novel recanalization techniques.

Adult↗