Coil embolization to occlude aortopulmonary collateral vessels and shunts in patients with congenital heart disease

Gianturco coils were used to embolize 77 vessels in 54 patients: 58 aortopulmonary collateral vessels, 14 Blalock-Taussig shunts, 3 arteries involved in pulmonary sequestrations and 2 venae cavae. Embolization resulted in total occlusion in 53 (69%), subtotal occlusion in 19 (25%) and partial occlusion in 3 (1 intentional). Two embolizations failed to reduce flow. Thus, 72 (95%) of 76 embolizations in which complete occlusion was the intended result resulted in total or subtotal occlusion. Analysis of the results demonstrates that completely occluded collateral vessels were longer and had a smaller diameter than did incompletely occluded vessels. Complications included six cases of inadvertent embolization to the pulmonary arteries (n = 5) or the aorta (n = 1); three were retrieved and three were left without symptoms. In addition, there was a case of severe hemolysis after intentional partial occlusion of a Blalock-Taussig shunt. The results demonstrate that coil embolization can be an effective procedure for managing a wide variety of aorto-pulmonary collateral vessels and shunts in children with congenital heart disease.     

Catheter closure of coronary artery fistulas

Coronary artery fistulas are rare and vary widely in their morphological appearance and presentation. This paper presents experience of catheter closure of coronary artery fistulas in 40 patients. Catheter closure was performed with a variety of techniques, including detachable balloons, stainless steel coils, controlled-release coils, controlled-release patent ductus arteriosus (PDA) coils, and Amplatzer PDA plug. The vast majority of the fistulas were occluded with coils and in particular, controlled-release coils. Successful occlusion of the fistula was achieved in 39 (97%) of 40 patients. In one patient, the detachable balloon deflated prematurely and the patient underwent elective surgery. One 4-month-old infant died approximately 6 hours after the procedure. Immediate occlusion of the coronary artery fistula occurred in 33 (82%) of patients and late occlusion in 4 patients. Thus overall, total occlusion was achieved in 37 (97%) of 39 patients. The main complication was embolization of the occlusion device, which occurred in 6 (17%) of cases. In one of these cases, a detachable balloon deflated prematurely, and in five patients, coils embolized and were retrieved. In one of the patients, all six coils embolized 24 hours after the procedure but were retrieved, and further coils were implanted successfully. Controlled-release coils have made an important contribution to the technique of catheter closure of coronary artery fistulas. Catheter closure of these fistulas is an acceptable alternative to the standard surgical treatment.     

Respiratory pharmacology. Antithrombotic and fibrinolytic therapy

Antithrombotic therapy with heparin is effective in reducing the incidence of thromboembolic disease when given prophylactically to high-risk patients. Heparin followed by oral antithrombotic therapy is accepted practice for the management of established thromboembolism. Fibrinolytic therapy has been demonstrated to be effective in recanalization of vessels occluded by thrombus, but is contraindicated if the effect of peripheral embolization from the occlusion is likely to result in severe morbidity. The use of heparin and oral antithrombotic drugs is associated with an increased frequency of bleeding, and requires careful clinical and laboratory control, for which the best methods have not yet been determined. Low-molecular-weight preparations of heparin have been shown to have effectiveness when administered once or twice a day, but not to have less risk for hemorrhage than regular heparin. Fibrinolytic therapy is entering a new phase with the conclusion of clinical trials of the newer agents that are associated with a reduced risk of systemic anticoagulation.     

Percutaneous closure of patent ductus arteriosus using special screwing detachable coils

Jackson screwing detachable coils, developed for arterial and venous embolization, have been successfully employed recently for the percutaneous occlusion of patent ductus arteriosus (PDA). Special screwing detachable coils were designed for closure of the PDA, and the experience gained by their use is described in this report. Occlusion was attempted in 29 patients with a minimal ductal diameter of 0.9–4.2 mm. Coils were successfully placed in all 29 patients. One coil, which embolized 10 min after detachment, was retrieved. In 26 patients (89%), complete closure was achieved. Only 35 coils were placed in 29 patients. Residual shunts in three patients are minimal, detectable only on color-flow mapping. Screwing detachable coils for closure of PDA are safe and effective for occlusion of PDA with a minimal diameter <4.2 mm. Embolization of the coil is very rare. A high closure rate is achieved with a low number of placed coils. Cathet. Cardiovasc. Diagn. 41:386–391, 1997. © 1997 Wiley-Liss, Inc.     

Transcatheter closure of patent ductus arteriosus and aorto‐pulmonary vessels using non‐ferromagnetic Inconel MReye embolization coils

Objectives . We report the use of non‐ferromagnetic embolization coils for transcatheter PDA closure. Background . Transcatheter patent ductus arteriosus (PDA) closure has been performed for 40 years. A number of devices have been used with varying degrees of success. Gianturco embolization coils have been used frequently since 1992 with excellent results. These coils are a stainless steel alloy, and create an artifact when subsequent MRI imaging is performed. Methods . Eight patients underwent right and left heart catheterization and transcatheter PDA closure. Angiography displayed a PDA with left to right shunting. The minimum PDA diameter was measured. An Inconel MReye coil was implanted using standard retrograde technique. A postimplant angiogram was performed. Evaluations were performed the following morning and after 2 months. Results . The median age was 5.5 years, median weight was 24 kg. The PDA minimum diameter was 1.7 mm (range 1.4–2.4 mm), with a median Qp:Qs=1.33:1. In all patients, the PDA was completely immediately closed using one Inconel coil. Two patients also had a small aorto‐pulmonary collateral vessel that was occluded using a separate Inconel coil. All patients had follow‐up evaluation the following day; the PDA remained completely occluded and there was no obstruction of the pulmonary artery branches or descending aorta. Seven patients had subsequent follow‐up and echocardiograms; the PDA remained completely occluded. There were no complications. Conclusion . The Inconel MReye coil is safe and effective for coil occlusion of small PDA and aorto‐pulmonary vessels. Additional studies are needed to define the maximum vessel diameter for Inconel coil occlusion. © 2008 Wiley‐Liss, Inc.     

Interventional occlusion of congenital vascular malformations with the detachable Cook coil system

INTRODUCTION: Nonsurgical closure of pathologic vascular communications can be achieved by coil embolization. Different systems used in patients with congenital heart disease (e.g., patent ductus arteriosus) allow controlled release of the devices. However, they are too stiff for coil occlusion of small or tortuous vessels. METHODS AND PATIENTS: The new detachable Cook coil system combines flexibility with a simple release control mechanism. Five children, age 8 days to 10 years, underwent heart catheterization for interventional occlusion of different vascular malformations (two coronary artery fistulas, two aortopulmonary collaterals, and one hemangioma). The diameter of the vessels varied between 1.8 mm and 3.6 mm and the length between 10 mm and 22 mm. RESULTS: Up to four 0.018" soft spiral coils were placed as distally as possible in the feeding vessels. In addition, in two patients, one to three J-shaped coils were placed inside and proximal to spiral coils. Positioning of the coils was controlled easily by radio-opaque markers. Counter-clockwise rotation of the delivery wire provided fast and safe detachment without movement of the detached coils. Control angiograms showed complete occlusion of the vessels within 10 minutes after delivery of coils. CONCLUSION: Interventional closure of vascular malformations can be successfully obtained with the detachable Cook coil system. This system offers safe and controlled placement of coils, and it works rapidly in an uncomplicated manner.     

Adequate heparinization during PTCA: assessment using activated clotting times

Heparinization during PTCA is often done empirically with an initial 10,000 unit bolus of heparin and subsequent additional boluses as deemed necessary to prevent thrombus formation and fibrin deposition. However, the initial 10,000 unit bolus may not result in adequate systemic anticoagulation in every patient, exposing some patients to risk of thrombus at the angioplasty site and subsequent reocclusion. In this non-randomized study, we assessed systemic coagulation during PTCA by retrospectively analyzing activated clotting times obtained in 108 consecutive patients. All patients had normal baseline prothrombin times and activated partial thromboplastin times. Patients who were on heparin prior to PTCA were excluded. Based on data from studies on heparinization during extracorporeal bypass an activated clotting time (ACT) of greater than 300 seconds was required. Twelve patients (11%) were observed to have activated clotting times of below 300 seconds after an initial 10,000 unit bolus of heparin. These patients required an additional 3,000-10,000 units of heparin to have systemic anticoagulation during PTCA. Symptoms of stable or unstable angina had no significant effect on heparin requirement, although there was a trend toward greater heparin resistance in unstable angina. We conclude that it is important to monitor the status of anticoagulation during PTCA, for 11% of patients undergoing PTCA require additional initial heparin bolus to achieve an ACT greater than 300 seconds and to be effectively anticoagulated. Careful monitoring of heparinization during PTCA may reduce the incidence of thrombosis.     

老年人自发性蛛网膜下腔出血诊治临床分析

目的 研究老年人自发性蛛网膜下腔出血患者的诊治策略及疗效. 方法 68例60岁以上自发性蛛网膜下腔出血患者,均行全脑血管造影,共发现颅内动脉瘤72个,47例患者(59个动脉瘤)接受栓塞治疗,6例患者(6个动脉瘤)行显微神经外科手术夹闭,7例患者选择保守治疗.结果 57个动脉瘤被成功栓塞,技术成功率为96.6%,其中致密栓塞40个(占70.2%),不完全栓塞17个(占29.8%);47例患者中,出院时根据格拉斯哥预后评分(Glasgow outcome scale,GOS)良好39例(占83.0%),较差7例(占14.9%),死亡1例. 结论 对于老年自发性蛛网膜下腔出血患者特别是存在颅内动脉瘤者,积极的干预措施如血管内栓塞治疗能取得较好的效果.     

Argatroban use during pediatric interventional cardiac catheterization.

Argatroban is a synthetic direct thrombin inhibitor that does not interact with or induce heparin-dependent antibodies. It is approved for use in adults for prevention and treatment of thrombosis associated with heparin-induced thrombocytopenia (HIT). It has been administered safely in adults with HIT during coronary interventions. There are no reports of argatroban use for anticoagulation in pediatric patients. The present case describes the use of argatroban during coil embolization of a Fontan fenestration in a child with a history of HIT. The patient received a single bolus dose of 150 microg/kg of argatroban at the onset of the intervention. The fenestration was successfully occluded with a detachable coil. The activated clotting time (ACT) was > 200 sec throughout the procedure. The ACT returned to baseline 72 min after the bolus. No complications occurred. This case demonstrates the safe and successful use of argatroban during a transcatheter intervention in a pediatric patient with a history of HIT. The use of argatroban is promising for anticoagulation in children who require an alternative to heparin.     

Closure of an iatrogenic aortocoronary arteriovenous fistula: transcatheter balloon embolization following failed coil embolization and salvage of coils that migrated into the coronary venous system.

We report a 50-year-old patient with successful percutaneous closure of a large inadvertent surgical aortocoronary arteriovenous fistula (shunt flow: 1.8 L/min). With initial embolization of multiple coils, no lasting occlusion of the large fistula could be achieved. Above that, two coils migrated into the coronary venous system. Following rescue of the migrated coils through a retrograde coronary sinus approach, the fistula was occluded using a detachable balloon. Follow-up angiograms confirmed successful closure of the fistula. In contrast to coil embolization, use of a detachable balloon seems to be the appropriate technique for percutaneous closure of such fistulas.     

Retrograde transcatheter occlusion of patent ductus arteriosus: preliminary experience in Gianturco coil technique without heparinization

BACKGROUND: The aim of this study was to report the initial experience of using the Gianturco coil (Cook Cardiology, Bloomington, Indiana) without heparinization to close patent ductus arteriosus (PDA). PATIENTS AND METHODS: Forty consecutive patients (30 females, 10 males) underwent transcatheter closure of a PDA via the right femoral artery approach without heparinization. Patients ages ranged from 7 months to 55 years (median, 6.8 years); weights ranged from 7.8 65 kg (median, 18.3 kg). Twenty-one patients had cardiomegaly (n = 21), congestive heart failure (n = 10), or both (n = 10). The PDAs measured 0.8 4.5 mm (median, 2.6 mm) at the narrowest diameter; the mean Qp/Qs ranged from 1.0 2.6 (1.4 +/- 0.4). The helical diameter of the coil that we chose was 1.7 times the narrowest PDA diameter. The length of the coil was sufficient to produce 4 or 5 loops. RESULTS: Successful coil placement was accomplished in all 40 patients. Thirty-five patients (87.5%) underwent single coil implantation, 2 patients (5%) had 2 coils, and 3 patients (7.5%) had 3 coils. Complete ductus occlusion was achieved in 80% of cases at the end of the procedure, while 8 patients had minimal shunt detected by aortography or echocardiography. The occlusion rate increased to 87.5% by the next day, 90% by 1 month, 92.5% by 3 months, 95% by 6 months, and 97.5% by 9 and 12 months. Only one asymptomatic patient had minimal residual shunt detected by color Doppler at 12 months follow-up. At a median follow-up of 17 months (range, 5 25 months), no patient had thromboembolism, endocarditis, coil migration, diminished femoral pulse or hemolysis. CONCLUSION: Our preliminary results suggest that retrograde transcatheter closure of PDA with the Gianturco coil without heparinization is feasible, safe and efficacious. A single coil allowed complete occlusion of PDA 3 mm in diameter.     

血管内介入治疗外伤性颈动脉-海绵窦瘘存在的问题

目的总结血管内介入治疗外伤性颈动脉一海绵窦瘘(TCCF)中存在的一些问题，探讨避免引起这些问题的技术方法。方法以可脱性球囊栓塞治疗68例TCCF患者，共进行栓塞术75次。1例经颈部切开穿刺，以球囊栓塞；2例经眼静脉入路以微弹簧圈栓塞海绵窦，其余则经股动脉入路栓塞。结果颈内动脉通畅率为66．2％，有3例在瘘口近端闭塞颈内动脉，有5例在栓塞术后3d内球囊过早泄漏，再次行栓塞术，1例栓塞瘘口后出现假性动脉瘤，1例出现眼静脉的动静脉瘘。结论以可脱性球囊栓塞TCCF是可靠的方法，但目前球囊的性能有待提高，以微弹簧圈栓塞海绵窦瘘可提高颈内动脉通畅率．双侧股动脉穿刺置管可减少并发症。     

Retrieval of embolized left atrial appendage devices

Percutaneous left atrial appendage (LAA) closure is gaining interest as an alternative option for prevention of strokes in patients with Atrial Fibrillation (AF), especially for those with contraindications to anticoagulation. Complications from these procedures are well described in the medical literature. LAA closures may lead to pericardial effusion, device‐associated thrombus, and device embolization. Understanding the reasons for embolization, strategies to avoid embolization, and the techniques for retrieval of LAA devices (ACP/AMULET and WATCHMAN) should be appreciated by endovascular implanters. We describe two cases of LAA device embolization that were both successfully retrieved percutaneously and other percutaneous techniques to safely retrieve embolized LAA devices. © 2016 Wiley Periodicals, Inc.     

凝胶微粒在血管内栓塞后的分布特点

目的探讨血管内栓塞后凝胶微粒在血管内的分布特点。方法对23例患者应用凝胶微粒进行术前栓塞,其中颅内动静脉畸形3例,鼻咽癌7例,副神经节细胞瘤13例。在光镜下观察凝胶微粒栓塞后的病理标本,并研究凝胶微粒在血管内的分布规律。结果共观察363根血管,其中317根血管(占87.3％)内都有1个凝胶微粒形成的栓子。在这些血管中,血管直径与凝胶微粒的直径呈正相关。凝胶微粒进入血管后,变形率<15％。当血管内的凝胶微粒为1个时,通过相关系数检验,P<0.01。结论挑选合适的凝胶微粒进行栓塞,可更加准确地闭塞瘤床血管和靶血管。     

Intermittent complete closure of the arterial duct

Intermittent functional closure of a patent duct has been reported both clinically and echocardiographically. We describe the case of a 6-year-old with intermittent complete closure of a patent duct occurring during attempted transcatheter closure. Recurrence of clinical and echocardiographic signs prompted restudy. A patent duct of moderate size was demonstrated and successfully occluded by coil embolization. The interventional aspects of this unusual condition are discussed.     

Restenosis following placement of an intracoronary heparin treated tantulum stent in the hyperlipidemic miniature swine model

Restenosis persists as an important factor limiting a favorable long term outcome following mechanical revascularization. The objective of the present study was to compare the effects of an intracoronary heparin treated tantalum prototype stent and balloon angioplasty on intimal hyperplasia, luminal diameter, and thrombosis in a porcine restenosis model. Male miniswine maintained on a high cholesterol diet and 325 mg aspirin per day underwent cardiac catheterization and oversized balloon injury to the right and left circumflex coronary arteries. Two weeks later one artery was either balloon injured again or implanted with a stent. No additional anticoagulation following stent placement was given, however aspirin was continued throughout the study. At four weeks, the coronary arteries were harvested and prepared for histologic examination and blinded quantitative morphometric analysis. The prototype stent was successfully deployed in 10 coronary arteries. Histological examination at explant revealed no evidence for thrombus or platelet aggregation. The angiographic luminal diameter of stented vessels was not significantly different from the diameter measured prior to implantation. In contrast, the angiographic diameter of balloon injured vessels was significantly decreased (4.4 +/- 0.4 mm2, balloon injured, vs. 5.8 +/- 3.3 mm2, control; p < 0.05). Stented arteries showed significantly more intimal hyperplasia, compared to balloon injured vessels (2.99 +/- 0.58 mm2 intimal area, stented arteries vs. 0.38 +/- 0.15 mm2 intimal area, control arteries; p < 0.05). In conclusion, heparin treated tantalum wire prototype intracoronary stents were successfully deployed in swine coronary arteries with no evidence for thrombus formation. Despite a significant intimal response, luminal diameter was preserved in stented vessels. The data suggest that a heparin treated tantalum wire prototype intracoronary stent may be an effective method of coronary revascularization that results in the preservation of luminal diameter without thrombotic occlusion.     

支架辅助弹簧圈治疗前交通动脉破裂微小动脉瘤

目的探讨支架辅助弹簧圈栓塞治疗前交通动脉破裂微小动脉瘤(直径≤3 mm)的安全性及有效性。方法回顾性分析2009年2月—2012年2月,第二军医大学长海医院神经外科采用支架辅助弹簧圈栓塞(支架后释放技术)治疗的26例前交通动脉破裂微小动脉瘤患者的临床资料,评价其安全性及有效性。结果①26例患者均获成功栓塞,其中致密栓塞15例(57.6%),瘤颈残余6例,大部分栓塞5例;载瘤动脉血流均通畅。②术后1.5～72.0个月行临床随访,26例中无一例再次发生动脉瘤相关性出血及血栓栓塞症状。1例Hunt-HessⅣ级患者术后6周死于心、肺功能衰竭。23例完全恢复正常,2例发生轻度神经功能障碍,但生活能够自理。③22例术后6～24个月获DSA随访,14例致密栓塞患者中无一例复发;5例瘤颈残余者中4例动脉瘤不显影,1例血栓进一步形成;3例大部栓塞的患者,2例动脉瘤不显影,1例血栓进一步形成。20例动脉瘤不显影的患者中,10例可见明显的愈合线。结论支架辅助弹簧圈栓塞技术治疗前交通动脉破裂微小动脉瘤安全、有效;支架后释放技术可提高动脉瘤栓塞率及长期预后的良好率。     

Short-term infarct vessel patency with aspirin and dipyridamole started 24 to 36 hours after intravenous streptokinase

The duration of intravenous heparin therapy required to maintain patency of the infarct-related artery after intravenous streptokinase is uncertain. Twenty-eight patients were prospectively treated with 1.5 million units of intravenous streptokinase within 4 hours of onset of chest pain. Intravenous heparin was begun after the streptokinase infusion was complete and was discontinued within 36 hours. Aspirin, 325 mg daily, and dipyridamole, 75 mg three times a day, was begun before the heparin was discontinued. Coronary angiography was performed both at 2 hours after completion of the streptokinase infusion and again at a mean of 8.7 (+/- 3.2) days after the initial catheterization. One patient died after treatment with streptokinase but before early angiography. In 21 of 27 patients (78%), Thrombolysis in Myocardial Infarction trial (TIMI) grade 2 or 3 perfusion in the infarct vessel was observed on initial angiography. Repeat angiograms were available in 17 of the 21 patients with initially patent vessels. Continued patency (TIMI grade 2 or 3) was found in 15 of the 17 patients (88%). Two of the four patients who did not undergo repeat angiography died, and the remaining two patients required coronary artery bypass grafting for unstable angina. Bleeding complications occurred in 6 of 27 patients (22%), with two (7%) requiring surgical evacuation of a groin hematoma. There were no instances of intracerebral bleeding and only two patients required transfusions. Thus, the combination of aspirin and dipyridamole following 36 hours of systemic heparinization after intravenous streptokinase infusion is associated with a reocclusion rate comparable to that which has been reported for more prolonged systemic anticoagulation with fewer hemorrhagic complications.     

Effect of controlled adventitial heparin delivery on smooth muscle cell proliferation following endothelial injury.

Continuous intravenous infusion of heparin suppresses smooth muscle cell proliferation in rats after endothelial injury but may lead to hemorrhage and other complications. The anticoagulant property has been removed from chemically modified heparin without loss of antiproliferative effect but use of such compounds is still limited. In this study ethylene-vinyl acetate copolymer matrices containing standard and modified heparin were placed adjacent to rat carotid arteries at the time of balloon dendothelialization. After 14 days arterial occlusion by smooth muscle cell proliferation was defined. Matrix delivery of both heparin compounds effectively diminished this proliferation in comparison to controls without producing systemic anticoagulation or side effects. In addition, this mode of therapy appeared more effective than the administration of the same agents by either intravenous pumps or heparin/polymer matrices placed in a subcutaneous site distant from the injured carotid artery. Thus, heparin's inhibition of smooth muscle cell proliferation after vascular injury might be most effective within the microenvironment of the injured vessel wall, and the accelerated atherosclerosis or restenosis that often follows angioplasty and other vascular interventions might best be treated with site-specific therapy.     

Arterial occlusion using a microguidewire as a radiofrequency electrode.

PURPOSE: To illustrate the use of superselective radiofrequency (RF) energy delivery for arterial occlusion in vessels requiring embolization. TECHNIQUE: A 3.0-F microcatheter and a 0.016-inch stainless steel microguidewire coated with polytetrafluoroethylene except for the floppy platinum-coiled tip are inserted into the diseased arteries. After positioning the microcatheter at the target site, the floppy tip of the microguidewire is advanced 1 to 2 cm beyond the microcatheter to act as an electrode. RF ablation is performed at a power of 20 watts until there was a rise in uncontrolled impedance. If occlusion is incomplete, embolic agents can be applied. The use of the technique is illustrated in 4 cases, 3 involving renal branch arteries and a large arteriovenous malformation in the buttock. RF energy was successful in occluding the target vessels in 3 cases; the other required additional embolization. There were no complications, and the patients had sustained occlusion of the lesions. CONCLUSION: Diseased arteries can be endovascularly occluded using a microguidewire to deliver radiofrequency energy. However, further development of the technique is needed to circumvent wire adhesion to the arterial wall and optimize RF delivery to avoid damage to adjacent structures.