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A small but definite recanalization rate has followed the vas ligation method of partial vasectomy for sterilization. Interposition of the fascial sheath between the divided ends of the vas reduced the recanalization rate to 0. Fulguration of the lumen of the cut vas ends was used but was not the significant factor in this zero recanalization rate.
This article, reflecting on the surgical recanalization of occluded peripheral arteries, has exposed the very essence of vascular surgery. Only the pioneering cardiac anomalies repaired by Gross (patent duct arteriosus, 1938), Blalock and Taussig (tetralogy of Fallot, 1944), and Crafoord and Nylin (coarctation, 1945) and the legendary aortic grafting operations of Oudot (occlusion, 1950) and Dubost and coworkers (aneurysm, 1951) are not a part of this article. The contributions to surgical recanalization of the occluded peripheral arteries are numerous. Some are well conceived, and others are innovative. Perhaps the most significant technique of all, endarterectomy itself, began purely as a serendipitous event. The startling impact of dos Santos' revolutionaly "disobliteration" was realized at once. Intimal injury during the operation did not cause inevitable thrombosis, as historically taught. Thus, all vascular interventions, either endarterectomy, graft repair, or the newer endovascular techniques discussed in this issue, would not have been developed without the understanding of the tolerance of the human intima to injury. Thromboendarterectomy, the basis of surgical recanalization of occluded arteries, unlocked the mystery of arterial rethrombosis after intervention. Recognizing these crucial facts, it will have a lasting place in the expanded discipline of vascular disease and its treatment. Dos Santos, the European founder of endarterectomy, and Wylie, the American pioneer and proponent of endarterectomy, were great friends in life (Fig. 4) and would certainly be pleased to see the further development of technology aimed at the treatment of atherosclerotic obstruction of the peripheral arteries.
At present, percutaneous peripheral ultrasound angioplasty should be considered in those patients with symptoms of claudication or resting limb ischemia. With the development of an over-the-wire system, we treat patients with suprageniculate or infrageniculate lesions. It is expected that the over-the-wire probe will allow application of ultrasound angioplasty not only to lesions below the knee but to contralateral vascular occlusions as well. An intraoperative device for plaque ablation and arterial recanalization is in development for use in less accessible sites such as the coronary arteries. Experimental studies have shown that catheter-delivered therapeutic ultrasound recanalizes complete occlusions, reduces stenoses, dissolves thrombus, vasodilates, and enhances arterial distensibility. The potential clinical applications of therapeutic ultrasound include recanalizing total arterial occlusions, dissolving thrombi, facilitating balloon angioplasty by increasing arterial compliance, and as a stand-alone angioplasty device.
BACKGROUND: Spontaneous recanalization in a completely thrombosed giant aneurysm is a very rare condition. CASE DESCRIPTION: An 18-year-old woman presented with a serpentine variety giant aneurysm of the posterior cerebral artery, in which spontaneous recanalization of a completely thrombosed lumen was demonstrated on magnetic resonance imaging and angiography. The patient was treated by trapping of the parent artery and aneurysmectomy. CONCLUSION: This case will provide insight into the potential for spontaneous recanalization in completely thrombosed giant aneurysms.
We describe the use of a carotid filter in preventing distal emboli during the recanalization of an occluded left iliac stent two months earlier. The filter was reversed and introduced through an ipsilateral 6 French sheath along its 0.014" guidewire and placed against the occluded stent. The stent is recanalized using a hydrophilic guidewire controlaterally and a new stent was inserted into the old one. The filter was retracted into the introducer by pulling cut the special 0.014 guidewire, with a 0.018" diameter tip, and the whole system was removed via the left common femoral artery. Many emboli were found in the removed filter. We noted that the recanalization of an occluded stent causes more distal embolization than the native iliac artery. This technique allows placing the filter between the embolic lesion and the distal arterial territory, without passing through the lesion, especially since fibrinolysis may not be efficient in 2-months-old occlusions.
The purpose of this study was to assess the potential of intraarterial ultrasound for in vivo recanalization of atherosclerotic total occlusions. Ultrasound energy at a frequency of 20 kHz was applied with a prototype solid wire probe to 12 surgically implanted occluded human atherosclerotic arterial xenografts, 9 of which were calcified, as well as to the intimal surface of 12 normal canine arteries. In both the normal canine arteries and the atherosclerotic occluded xenografts, there was no angiographic evidence of vasospasm, thrombosis or arterial dissection. Eleven of the 12 atherosclerotic complete arterial occlusions were resistant to passage of a conventional guide wire or probe without ultrasound energy. However, the occlusions were recanalized after administration of 15 s to 4 min (mean 1.5 +/- 1.3 min) of intermittent ultrasound energy. After ultrasound, 8 of the 12 vessels underwent balloon angioplasty. Angiographic residual stenosis after ultrasound alone was 62 +/- 24% and after combined ultrasound and balloon angioplasty, 29 +/- 13%. Although routine angiography did not reveal arterial emboli, high resolution cut films did demonstrate a few distal nonocclusive thrombi of a size similar to that reported with other recanalization methods. Histologic studies demonstrated changes similar to those after balloon angioplasty, with focal cracking of the fibrotic and calcified plaque. The findings demonstrate that ultrasound energy applied through a catheter delivery system can be used in vivo to open completely obstructed atherosclerotic vessels. These studies suggest that it might be clinically feasible to use the ultrasound probe to create a lumen, allowing subsequent balloon dilation.
OBJECTIVES: This study sought to prospectively evaluate the performance of a laser guide wire in crossing chronic total coronary occlusions in patients with a failed previous mechanical guide wire attempt. BACKGROUND: Despite continued refinement of mechanical hardware available for coronary angioplasty, restoration and maintenance of blood flow through a chronically occluded coronary artery remains a true challenge. METHODS: Fifty patients with a chronic total coronary occlusion and a previous failed attempt at recanalization using mechanical guide wires were included. A mechanical attempt to cross the occlusion was repeated. In case of failure, an additional attempt was made with the laser guide wire. RESULTS: The median age of occlusion was 22 weeks (range 5 to 200), and the occlusion length was 23 +/- 11 mm (mean +/- SD). A repeat mechanical attempt was successful in six cases (12%). Dissection occurred in five other cases, and device crossover was not attempted. Thus, in 39 patients an attempt was made with the laser guide wire, with successful recanalization in 23 (59%). Thereby the overall success rate increased from 12% to 58% (29 of 50 patients). The amount of contrast medium used was 515 +/- 154 ml, fluoroscopy time was 99 +/- 43 min, and total procedure time was 2 h 48 min (+/- 55 min). Procedural success was achieved in 26 cases and clinical success (procedural success without in hospital events) in 24. In-hospital events were two non-Q wave myocardial infarctions related to subacute reocclusion. In one patient, a balloon dilation after laser guide wire perforation resulted in tamponade requiring pericardiocentesis. After a successful procedure, the angina class decreased from 2.9 +/- 0.2 to 1.4 +/- 0.7 at 3 months of clinical follow-up. Six month angiographic follow-up was completed in all 24 eligible patients and showed vessel patency in 20 (80%). CONCLUSIONS: The use of the laser guide wire for recanalization of chronic total coronary occlusions refractory to treatment with mechanical guide wires is feasible and relatively safe and was successful in 59% of cases. This device must thus be considered a valuable addition to the interventional armamentarium and accordingly will be evaluated in a randomized clinical trial.
Angioplasty of chronic total occlusions (CTOs) has lower technical success rates with longer procedure times and poorer outcomes. Subintimal recanalization remains limited by the lack of controlled re-entry into the true lumen of the target vessel. We report our experience using a commercially available catheter-based system equipped with an intravascular ultrasound scanner to achieve controlled true lumen re-entry in patients with peripheral CTOs. In a 4-month period, 6 patients with lower extremity (LE) ischemia from CTOs were treated. Occluded segments were crossed subintimally, and controlled re-entry was secured using the CrossPoint TransAccess catheter. This 6.2 F dual-lumen catheter contains an integrated 64-element phased array intravascular ultrasound scanner enabling targeting of structures. Intravascular ultrasound-guided luminal re-entry was achieved by advancing a 24-gauge needle to a desired length and delivering a 0.014" guide wire into the target lumen. The occluded segments were balloon dilated and stented using self-expanding nitinol stents. Effective luminal re-entry and re-establishment of antegrade flow occurred in all 6 patients. Time to recanalization ranged from 5 to 10 minutes. All patients were free of ischemic symptoms at 1 to 5 month follow-up. There were no procedure-related complications. Our preliminary results demonstrate the feasibility of using this catheter system for subintimal recanalization with controlled re-entry in CTOs. This approach can improve the technical success rate, reduce the time of the procedure, and minimize potential complications.
Percutaneous microwave coagulation for recanalizing stents occluded by tumor ingrowth has been reported. With this technique, however, the percutaneous drain diminishes the quality of life in patients with unresectable tumors and a limited prognosis. Transpapillary microwave ablation was attempted in three patients with occluded stents. After a sheath had been inserted into the proximal hepatic duct across the occluded region, a microwave electrode was introduced into the intrahepatic duct via the sheath. We used microwave therapy with an output power of 40 W, based on our previous in vitro study. Except in one patient, the stents were successfully recanalized with one or two attempts. In one patient who underwent ablation in the intrahepatic duct, a 1.8-mm electrode enabled recanalization of the stent. In another who underwent ablation in the extrahepatic duct, however, a larger electrode was required. There were no procedure-related complications. Transpapillary microwave coagulation of occluded stents appears to be an alternative to percutaneous microwave coagulation with an electrode fitting the stent size. The technique might be easier with the use of a redesigned electrode with a guide wire lumen.
BACKGROUND: Although plasma brain natriuretic peptide (BNP) levels have been widely measured in patients with acute myocardial infarction (AMI), it is still uncertain whether the early recanalization modulates the levels and whether the levels can predict chronic stage left ventricular function. This study was designed to elucidate these issues. METHODS: In 80 consecutive patients with AMI, plasma BNP levels were measured at admission and at 4 hours, 24 hours, 48 hours, and 1 month after admission. RESULTS: In 35 of the 80 patients, the infarct-related artery was patent within 6 hours from the onset of MI (6-hour patency group), and in 27 patients, the artery was still occluded after 6 hours (6-hour occlusion group). The remaining 18 patients in whom it was unclear whether recanalization of the infarct-related artery had occurred within 6 hours or not were excluded from the analyses. In the 6-hour patency group, the BNP level gradually increased and reached a maximum value at 24 hours after admission. In the 6-hour occlusion group, the level increased more, with the values at 4 hours, 24 hours, and 48 hours significantly higher than those in the 6-hour patency group (86 +/- 18 pmol/L versus 35 +/- 8 pmol/L; P <.01; 112 +/- 13 pmol/L versus 74 +/- 9 pmol/L; P <.05; 102 +/- 15 pmol/L versus 53 +/- 11 pmol/L; P <.01). Chronic stage left ventricular function was correlated with not only the BNP level at same stage but also that at 24 hours and that at 48 hours after admission. Multiple regression analysis indicated that the BNP level at 24 hours was the most powerful predictor of chronic stage left ventricular function. CONCLUSION: Plasma BNP levels can predict subsequent cardiac function. In addition, the importance of early recanalization may also be supported with BNP kinetics.
BACKGROUND: Controversy exists regarding early reopening and recanalization after successful (complete) coil occlusion of the patent ductus arteriosus (PDA). METHODS: Patients with successful PDA coil occlusion were reviewed with regard to PDA size and type, coil size, number of coils, and delivery technique. Follow-up echocardiograms at <24 hours, 6 months, and >12 months were reviewed for residual PDA shunt, left pulmonary artery (LPA) stenosis, and aortic obstruction. RESULTS: Successful coil occlusion was achieved in 94 patients. On the initial (<24 hours) echocardiogram, 76 of 92 (83%) had complete PDA occlusion, 5 of 92 (5%) had mild LPA stenosis, and no patient had aortic obstruction. Follow-up at 6 months was available in 70 patients, 57 with complete occlusion on the initial echocardiogram. PDA reopening was found in 3 of 57 patients (5%). Larger PDA diameter was associated with residual shunt (2.40 +/- 0.40 mm versus 1.87 +/- 0.53 mm; P <.01). Disagreement between the initial and 6-month echocardiogram was found in 11 of 70 patients (16%). Intermediate follow-up (median, 30 months; range, 12 months to 5.3 years) was available in 46 patients, 38 with complete occlusion on the 6-month echocardiogram. No patient (0 of 38) with a normal echocardiogram at 6 months developed recanalization, LPA stenosis, or aortic obstruction. CONCLUSION: These data suggest that: (1) routine echocardiography immediately after PDA coil occlusion is unnecessary; (2) early PDA reopening is uncommon; and (3) PDA recanalization does not occur if complete echocardiographic closure is documented 6 months after coil occlusion. Additional follow-up examination in these patients may not be necessary.
Ridogrel, a compound with the dual property of inhibiting the synthesis of thromboxane and blocking the receptors of thromboxane/prostaglandin/endoperoxides, has been shown to accelerate the speed of recanalization and to delay or prevent reocclusion during systemic thrombolysis with tissue plasminogen activator in experimental animals. Ninety patients who had not taken any antiplatelet drugs within the last 10 days were randomized to either intravenous ASA 250 mg immediately before the thrombolytic treatment and 100 mg once a day orally thereafter or ridogrel 300 mg i.v. before thrombolytic treatment and 300 mg b.i.d. orally thereafter. All patients were given intravenous heparin concomitantly with alteplase. The patency of the infarct-related artery was determined by coronary angiography before the administration of the thrombolytic agent and by repeated coronary angiography every 15 min until the end of the administration of alteplase. A final angiogram was obtained 48 to 72 h later. At 90 min, the recanalization and patency rates were the same in the two treatment groups with no intergroup difference in the speed of recanalization.
The effect of a selective thromboxane A2 (TxA2) receptor antagonist, SQ 30,741, on streptokinase-induced thrombolysis was examined in pentobarbital-anesthetized cynomolgus monkeys. The intimal surface of a stenosed carotid artery was stimulated with 100 microA anodal current to produce an occlusive thrombus. After 45 min of zero blood flow, a 1-h intraarterial (i.a.) infusion of streptokinase (680 U/min) was injected proximal to the thrombus. Five minutes before streptokinase (SK) intravenous (i.v.) infusions of heparin (200 U/kg + 120 U/h) and either SQ 30,741 (2 mg/kg + 2 mg/kg/min, n = 8) or vehicle (1 ml/h saline, n = 7) were started and maintained for 3 h. In four monkeys not given streptokinase or heparin, no recanalization was detected and occlusive thrombi were observed after 3 h. All animals receiving streptokinase were recanalized. SQ 30,741 had no effect on return of flow during streptokinase infusion, but increased average reflows during the second (60%, p less than 0.05) and third hours (159%, p less than 0.01). Average blood flows were decreased from the second to third hours with vehicle (p less than 0.001) and remained stable with SQ 30,741. Thromboxane antagonism also increased minimal blood flows during the third hour (438%, p less than 0.01) and decreased the total time reoccluded by 73% (p less than 0.05). However, SQ 30,741 had no effect on the time to recanalization, the maximum reflow, and both number of animals reoccluded and average number of reocclusions. Fibrinogen levels were equivalently diminished (8%, p less than 0.05), and platelet counts were unaffected in both treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS)
OBJECTIVE AND IMPORTANCE: Dural sinus thrombosis can lead to intracranial venous hypertension and can be complicated by intracranial hemorrhage. We present a case report of a patient who underwent endovascular recanalization and stenting of a thrombosed occipital sinus. CLINICAL PRESENTATION: A 13-year-old patient with a history of chronic sinus thrombosis refractory to anticoagulant therapy presented with acute onset of aphasia and hemiparesis. Computed tomography and magnetic resonance imaging revealed hydrocephalus and cerebral edema. Angiography delineated multiple dural arteriovenous fistulae and persistent occlusion of the posterior sagittal, occipital, and bilateral transverse dural sinuses with retrograde cortical venous drainage. INTERVENTION: After embolization of the dural arteriovenous fistulae, a transvenous approach was used to recanalize and perform balloon angioplasty of the right internal jugular vein and the occipital and left transverse sinuses, resulting in subsequent clinical improvement. The patient's condition deteriorated 3 days later with reocclusion of both balloon-dilated sinuses. Repeat angioplasty and then deployment of an endovascular stent in the occipital sinus were performed, and reestablishment of venous outflow was achieved, resulting in a decrease of intracranial venous pressure from 41 to 14 mm Hg and neurological improvement. At the 3-month follow-up examination, the stented occipital sinus remained patent and served as the only conduit for extracranial venous outflow; the patient remained neurologically intact at the 12-month follow-up examination. CONCLUSION: This is the first report of mechanical recanalization, balloon angioplasty, and stent deployment in the occipital sinus to provide sustained venous outflow for the treatment of venous hypertension with retrograde cortical venous drainage in a patient with dural pansinus thrombosis refractory to anticoagulant therapy.
OBJECTIVE AND IMPORTANCE: The frequent association of dural arteriovenous fistulae (DAVFs) and dural sinus thrombosis may render the treatment of these complex lesions difficult. We report a case of DAVF eradicated by recanalization of the chronically thrombosed transverse sinus (TS) and sigmoid sinus followed by balloon angioplasty and stent deployment at the site of the fistula. CLINICAL PRESENTATION: A 52-year-old man presented with a Type IV DAVF of the left TS with widespread white matter changes secondary to venous hypertension. Arterial feeders arose from the left internal carotid, external carotid, and vertebral arteries. The distal segment of the left TS, the left sigmoid sinus, and the proximal segment of the right TS were occluded. Reverse flow was observed in the deep venous system and in the superior sagittal sinus. INTERVENTION: Endovascular access was gained through the left internal jugular vein. Mechanical recanalization of the thrombosed left TS and sigmoid sinus was followed by balloon angioplasty and placement of six overlapping stents extending from the TS to the proximal internal jugular vein. Angiograms performed after surgery showed resaturation of antegrade venous drainage as well as complete eradication of the fistulous connections. The patient was discharged with an improving clinical CONCLUSION: Recanalization of a chronically occluded dural venous sinus through a jugular approach is feasible. In addition to eradicating cerebral venous hypertension by reestablishing antegrade venous drainage, balloon angioplasty and stent deployment at the DAVF site produced complete closure of the fistula. This may prove to be a new therapeutic strategy for management of DAVF.
BACKGROUND: Comparison of different plasminogen activators is difficult because conventional endpoints such as mortality are relatively insensitive to potential differences in efficacy with respect to rapidity of recanalization of infarct-related arteries. METHODS: This study was performed to determine whether valid comparisons could be made by means of biochemical endpoints that have been demonstrated previously to permit estimation of the time of opening of an infarct-related artery in experimental animals and in patients. The method is based on time-dependent interconversion of isoforms of creatine kinase mediated by carboxypeptidase N, an enzyme present in excess in circulating blood. A small subset of 39 patients studied in the ASsessment of the Safety and Efficacy of a New Thrombolytic agent (ASSENT-2) trial were evaluated to determine the feasibility of using the creatine kinase isoform method for comparison of two tissue-type plasminogen activators (tPA), recombinant tPA (r-tPA) and TNK-tPA. RESULTS: Early recanalization (within 40 min of the onset of treatment with the plasminogen activator) occurred in 56% of patients treated with r-tPA and 76% of those treated with TNK-tPA. CONCLUSIONS: Differences in the efficacy of plasminogen activators with respect to rapidity of recanalization appear to be readily detectable by means of assaying creatine kinase isoforms in serially acquired blood samples under conditions that permit widespread application of the approach developed.
Subintimal recanalization can be a useful procedure in selected patients with severe peripheral vascular disease with tissue loss or rest pain and limited surgical bypass options. Technical failure occurs in approximately 20% of patient who undergo percutaneous intentional extraluminal recanalization due to inability to reenter the distal true lumen. A technique to improve technical success when performing subintimal recanalization when there is failure to reenter the distal true lumen or possibly when there is a limited segment of patent distal target vessel for reentry is proposed. Further evaluation of this technique is necessary to confirm its safety and determine its technical and clinical success.
Treatment with radiofrequency (RF) energy can be used to ablate or perforate tissues. The latter involves lower power, higher voltage, and much shorter treatment time, and it is thought to induce much less collateral tissue damage. To date, RF perforation has been successfully used for various cardiac interventions; however, to our knowledge, there has not been a report of its use for peripheral vascular disease. This report describes the successful recanalization of a longstanding occlusion of a left subclavian vein in a 73-year-old woman with polycystic kidney disease and end-stage renal disease undergoing chronic hemodialysis treatment via an upper-extremity arteriovenous fistula. Multiple previous attempts at mechanical recanalization were unsuccessful. Recanalization was achieved by RF perforation with use of a PowerWire RF guide wire.