• Journal of Chest Surgery
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• v.37 no.1
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• pp.50-55
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• 2004

Background: Transcranial Doppler ultrasonography (TCD) can detect microembolic signals (MES) in the patients with a potential embolic source. Clinical significance of MES has not been demonstrated in patients with prosthetic mechanical heart valves. We studied the correlation between cerebral thromboemoblic events after the mechanical heart valve surgery (MHVS) and residual MES during TCD monitoring with 100% oxygen inhalation in patients with mechanical heart valves. Material and Method: Twenty patients with previous cerebral thromboemoblic events after MHVS and a sex- and age-matched control group (n=30) were studied. TCD monitoring was performed from unilateral middle cerebral artery. After baseline monitoring for 20 minutes, 61 of oxygen was inspired for 40 minutes. Result: The site of valve and the duration after MHVS of the patients did not differ from those of controls. During baseline monitoring, there was no significant difference in MES prevalence or counts compared to controls. During oxygen inhalation, patients showed a higher MES prevalence (55%, 27.6%, p=0.045) and a more frequent MES counts (p=0.027) compared to controls. Conclusion: TCD monitoring with oxygen inhalation may be useful to differentiate clinically significant MES in patients with mechanical heart valve.

• Journal of Chest Surgery
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• v.36 no.5
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• pp.316-320
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• 2003

Background: The detection of circulating microemboli by transcranial Doppler ultrasonography (TCD) has the potential to select the patients with high risk for future symptomatic brain embolism. We prospectively evaluated the positive rate and the frequency of microembolic signals (MES) before and after the heart valve surgery (HVS). Material and Method: Fifty in-patients with heart valve disease were enrolled in this study. Patients with history of previous stroke or heart valve surgery were excluded. Two unilateral TCD monitoring sessions were peformed from middle cerebral artery for 1-hour, before and after HVS. Result: Mechanical Heart valves were implanted in 28 patients, tissue valves were implanted in 10 patients, and remaining 12 patients received mitral valve repair. Positive rate of MES was significantly increased after HVS (50%), compared to that of before HVS (8%, p=0.00). There was no relation between MES after HVS and intensity of anticoagulation, cardiac rhythm, patients' age, and history of hypertension. The positive rate of MES after implantation of mechanical heart valve (71.4%) was significantly higher than those after implantation of tissue valve or mitral valve plasty (p=0.002). Conclusion: Positive rate of MES was increased significantly after the implantation of HVS. The changes of MES in those with mechanical prosthesis may be related to the increased risk or embolism after Hvs.

• Journal of the Korean Society of Radiology
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• v.81 no.3
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• pp.739-745
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• 2020

A major concern associated with carotid artery angioplasty and stenting (CAS) is a periprocedural distal cerebral embolization. To prevent distal embolization, embolic protection devices (EPDs) have been developed. However, the risk of cerebral embolism after protected CAS in patents with a vulnerable plaque is controversial and either a silent or a symptomatic stroke can occur despite the use of EPDs. Here, we report a case of a massive cerebral microemboli after a protected CAS using a distal filter EPD for a vulnerable plaque with a lipid rich necrotic core and intraplaque hemorrhage.

• Journal of Chest Surgery
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• v.30 no.2
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• pp.172-178
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• 1997

We present a etrospective analysis of arterial embolectomies performed at the Inje University Seoul Paik Hospital. During the period of March 1987 Feburary 1996 twenty-six patients underwent embolectomies, eighteen patients were male and eight patients were female, mean age of patients was 56.8 years. Rest pain was the chief complaint in 24 patients, the remaining two patients complained of long term history of claudication after recovery of acute symtoms. But only 10 patients had sensBrylmotor symtoms. Heart was the most common source of embolization and frequent predisposing factor of embolism was ischemic heart disease in 8 cases and valvular heart disease in 11 cases. The sites of embolization were upper extremities artery in 6 cases, saddle embolism in 2 cases, lower extremities artery in 18 cases and the most common site of embolism was femoral artery in 1 1 cases. Preoperative angiography was taken in the diagnosis and planning of the embolectomy in 1) patients while in the other patient p eoperative angiography was not taken. Only two cases were operated within the golden period of 6 hours and other cases were operated in more than 6 hours after embolization. In all patients, the Fogarty embolectomy catheter was used without bypass surgery via bachial ateriotomy in the embolism of upper extremities artery, bilateral groin approaches in the saddle embolism and transfemoral approach in the embolism of lower extremities artery. However 3 patients were re-operated via transpopliteal approach in the distal poplitiotibial embolism. Eighteen patients received perioperative anticoagulation therapy by heparin or fraxiparine and wafarin was used in 17 patients at the time of discharge and the indication of anticogulation was patients of valvular heat disease andfor atrial fibrillation, peripheral artery atherosclerosis and recurrent embolism. Postoperative results of the embolectomy were as follows: fouteen pateints had excellent results, five cases had symtom improvement after re-operation, B. K. amputation in 1 case who had severe atherosclerosis of lower extremities, recurrent embolism in 1 case and death in 2 cases the cause of death were acute renal failure and cerebral artery embolism, respectively. The complications of the embolectomy were reperfusion syndrome, pseudoaneurysm and intimal dissection in one case each. Conclusively the problems of embolism is delayed diagnosis and increasing number of old aged patient who had suffered from ischemic heart diease. Preoperative angiography was not always needed for embol ectomy. Selective anticoagulation therapy can decrease incidence of re-embolism. In the distal poplitiotibial embolism, embolectomy of tibial artery was difficult.

• Journal of the Korean Society of Radiology
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• v.82 no.4
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• pp.1011-1017
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• 2021

Bone cement embolism often occurs during percutaneous vertebroplasty. Bone cement pulmonary arterial embolism generally requires no treatment because of the small size and asymptomatic manifestation. Intracardiac bone cement embolisms are rare but associated with a risk of severe complications. Intracardiac bone cement embolisms are mainly removed through open heart surgery. To the best of our knowledge, only three cases of intracardiac bone cement embolisms removed with interventions have been reported. Here, we report another case of successful transcatheter retrieval of a 6-cm-long cement embolism in the right atrium after percutaneous vertebroplasty. The embolus broke in half and migrated to the right pulmonary artery intraoperatively. Using two snares and a filter retrieval device, we advanced from opposite directions. Further, we gently grasped and pulled the fragments of the right pulmonary artery and aligned them in a linear fashion directly into the sheath for uneventful removal.

• Journal of Veterinary Clinics
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• v.25 no.1
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• pp.23-26
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• 2008

A 2-year-old, female, Turkish Angora cat was presented due to hindlimb paralysis with 2-day history of vomiting and depression. Physical examination revealed weak femoral pulse and cyanotic footpads of hind limbs. Chest auscultation, thoracic radiography, and electrocardiogram were no remarkable. Abdominal ultrasonography showed suspected hyperechoic thrombus in abdominal aorta. Underlying causes of the arterial thromboembolism were not found on multiple diagnostic examinations and the cat was diagnosed as idiopathic saddle thromboembolism. Despite 4-week regimen with heparin sodium, aspirin, and diltiazem, the hind limbs were progressively and irreversibly necrotized. Therefore, coxofemoral amputation was performed. After surgery, the clinical condition of this cat returned to normal without further complications.

• Journal of Veterinary Clinics
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• v.31 no.6
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• pp.507-510
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• 2014

An 8 month-old female Pomeranian dog was presented with major complaints of heart murmur and cardiomegaly. Diagnostic study found the left-to-right patent ductus arteriosus (PDA) with moderate heart failure (ISACHC II). The PDA occlusion was successfully accomplished using a $5mm{\times}3loops$ embolic coil through right femoral artery. Two months later, the dog came back to clinic with marked hypotension, severe diarrhea and pleural effusion. Diagnostic study found severe pulmonary hypertension and tricuspid regurgitation. The clinical condition was controlled by the administration of sildenafil (3 mg/kg, PO, TID). However, the dog was expired by dislodged embolic coil and inconsistent medication by the owner. Postmortem study found the pulmonary hypertension was occurred by the abnormally dislodged embolic coil. Although the embolic coil is widely used for PDA occlusion in toy dogs with PDA, the more careful evaluation for the size and shape of PDA is necessary to minimize the risk of dislodgement of pre-placed coil.

• Journal of radiological science and technology
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• v.32 no.1
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• pp.61-67
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• 2009

Purpose : The purpose of this study was to investigate the applicability of poly-L-guluronic alginate (PGA) gel in vascular embolization with angiography simulation. Materials and Methods : To prepare a gel-forming PGA from no guluronate-rich Laminaria japonica, a new acid hydrolysis method was employed with a lower HCL concentration (0.03 M) and a shorter treatment time (5 min). The obtained PGAs were selected based on gel stability and viscosity. Glass aneurysm model was used to simulate gel embolization in vitro. Then, finally, the PGA was used to embolize the renal vascular system by using a rabbit model and angiography. Results : Glass aneurysm model was made to simulate gel embolization procedure. PGA solution was injected from pump through 2-way catheter. Subsequent injection of $CaCl_2$ successfully formed gels inside aneurysm model that conforming to its inner contour. In rabbit model, first, renal artery and aorta leading to the right kidney were ligated to block blood flow, then conventional contrast agent was injected through aorta to check the arterial patency to the left kidney. In sequential artery injection method, PGA and $CaCl_2$ were injected through renal artery sequentially via a single catheter. Re-injection of contrast agent after removing ligated aorta showed blood flow to the right kidney but no flow in the left kidney. This result demonstrated a complete blocking of blood flow due to gel formation in vascular bed of the left kidney. Conclusion : Instillation of calcium alginate into aneurysm model and arterial system in vivo produced an embolization that better fills and conforms to the contour of aneurysms or blocking vascular bed completely. Therefore, PGA was effective endovascular occlusion materials and provide an efficiency of vascular angiography.

• Polymer(Korea)
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• v.37 no.4
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• pp.486-493
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• 2013

The structure, morphology, and physical properties of syndiotatic poly(vinyl alcohol) (s-PVA) gel spun fibers were investigated to prepare polymeric embolization coils. S-PVA was prepared by saponification of the poly(vinyl acetate)/poly(vinyl pivalate)(PVAc/PVPi) copolymer. The viscosity of s-PVA solutions showed shear thinning behavior and the solution formed a homogeneous phase. Based on shear viscosity change with concentration, the optimum dope concentration was selected as 13 wt%, after which s-PVA fibers were spun and the solvent was removed. The fibers were then drawn with a maximum draw ratio of 15. A polymeric embolization coil was made of the s-PVA gel-spun fibers. The fibers were wound densely onto rigid rod and then annealed at different annealing temperatures. The polymeric embolization coil annealed at $200^{\circ}C$ was similar to metallic coils and its shape was maintained well after extension. Overall, gel-spun PVA fibers performed well for the preparation of primary and secondary coils to replace metallic coils.

• Korean Journal of Veterinary Research
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• v.41 no.3
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• pp.429-436
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• 2001

The present study was performed to investigate the effect of iohexol-ethanol mixture and barium-ethanol mixture on the induction of transcatheter renal artery embolization in healthy 18 dogs, which were divided into two groups of 9 dogs and the 9 dogs were divided into 3 subgroups of 3 dogs. The renal artery embolization was undertaken unilaterally with the dose of 1.5, 2.0, and 3.0 ml/kg iohexol-ehtanol mixture and with the dose of 0.2, 0.4, and 0.8 ml/kg barium-ethanol mixture. And serum chemistry on 0, 1,3, 7, and 14 days, intravenous pyelography on 7days, angiography on 14 days, and histopathology on 14 days were evaluated. Serum BUN and creatinine concentration of two groups with iohexol-ethanol mixture and barium-ethanol mixture administration were mildly increased a t 1 day after injection of embolic materials and then returned to baseline. No significant changes in BUN and creatinine levels occurred in any of dogs. In all dogs with the dose of 1.5 ml/kg iohexol-ethanol mixture, the renal arteries were not embolized. All dogs with the dose of 3.0 ml/kg died. In all dogs with the dose of 2.10 ml/kg, the treated arteries were completely occluded. In barium-ethanol mixture administered group, the renal artery in one dog with the dose of 0.2 ml/kg was not embolized. In all dogs with the dose of 0.8 ml/kg, the renal arteries were completely embolized, but loac overembolization occured in two dogs. All animals with the dose of 0.4 ml/kg had effective embolization and no evidence of radiopaque barium opacity in systemic arteries distal to the renal-artery was found. All embolized kidneys were shrunk and decreased in size in gross examination and were shown diffuse necrosis in histopathologic examination. In the present study, renal arteries were embolized with the dose of 2.0 ml/kg iohexol-ethanol mixture or 0.4 ml/kg barium-ethanol mixture. And it is considered that the dose had a satisfactory embolic effect.