Won-Heum Shim

Echocardiographic and morphologic characteristics of left atrial myxoma and their relation to systemic embolism.

We examined the relation between the echocardiographic morphology of cardiac myxoma and systemic embolism in 25 patients. Two distinct types of myxoma could be identified by echocardiography: round type characterized by solid and round shape with nonmobile surface (n = 13, 52%), and polypoid type characterized by soft and irregular shape with mobile surface (n = 12, 48%); multiple regression analysis revealed the polypoid type of tumor was the only independent predictor of systemic embolism (p = 0.0029).

Endovascular therapy combined with immunosuppressive treatment for occlusive arterial disease in patients with Takayasu's arteritis.

Purpose: To evaluate the feasibility and efficacy of endovascular therapy combined with immunosuppression for the treatment of arterial occlusive disease in patients with Takayasus arteritis (TA). Methods: From January 1998 to June 2003, 25 patients (22 women; age 37.8±15.5 years) with TA were treated with angioplasty for symptomatic lesions or with a hemodynamically significant aortic narrowing. The patients with active disease, defined as an increase in inflammatory markers (e.g., erythrocyte sedimentation rate [ESR]), were treated with immunosuppressive agents before intervention. Angioplasty was performed after the ESR had been normalized. Results: In the 25 patients, 58 vascular territories (7 aortic, 9 carotid, 3 vertebral, 11 subclavian, 2 superior mesenteric, 18 renal, 4 iliac, and 4 coronary arteries) were treated with angioplasty only (19 lesions) or with stents (39 lesions). The mean ESR when the vascular lesions were initially diagnosed was 35.6±26.2 mm/h, which fell to 18.5±7.8 mm/h after immunosuppressive therapy. The endovascular procedure was performed successfully in 52 (90%) of 58 lesions. During the mean 23.7±18.4-month follow-up, 9 (17%) treated segments restenosed; 4 were treated with repeat angioplasty. The overall cumulative primary clinical success rate was 82%; secondary clinical success was 90%. Conclusions: Endovascular therapy for stenotic lesions in patients with TA is safe and effective when disease activity is strictly controlled with immunosuppressive treatment.

Endovascular Therapy Combined with Immunosuppressive Treatment for Pseudoaneurysms in Patients with Behçet's Disease:

PURPOSE To evaluate the feasibility, efficacy, and outcome of endovascular therapy combined with immunosuppression for the treatment of arterial pseudoaneurysms due to Behçets disease. METHODS Eleven pseudoaneurysms (3 in the abdominal aorta, 3 in the subclavian artery, and individual lesions in the brachiocephalic artery, renal artery, common iliac artery, common carotid artery, and the descending thoracic aorta) in 9 patients with Behçets disease were treated with 10 stent-grafts and 1 self-expanding stent. All patients with elevated erythrocyte sedimentation rate (ESR) were treated with immunosuppressive agents (azathioprine, prednisolone) before and after the procedure. RESULTS Endovascular treatment was successful in all cases, without major adverse events. The ESR was reduced from 42.7+/-18.0 mm/h initially to 18.6+/-12.6 mm/h after immunosuppressive therapy prior to endovascular repair. During follow-up (mean 24.1+/-14.0 months, range 6-43), 8 of 11 lesions showed complete resolution. One stent-graft to treat a postsurgical recurrent carotid artery pseudoaneurysm was occluded, and an abdominal aortic pseudoaneurysm recurred; both patients stopped their medications. ESR during follow-up was 7.9+/-4.5 mm/h. CONCLUSIONS Endovascular treatment for pseudoaneurysms due to Behçets disease is feasible and effective when disease activity is strictly controlled with immunosuppressive therapy.

Improved Technical Success and Midterm Patency with Subintimal Angioplasty Compared to Intraluminal Angioplasty in Long Femoropopliteal Occlusions

Purpose: To compare the efficacy of subintimal angioplasty combined with primary stenting to intraluminal angioplasty with stenting for revascularization of long (>10 cm) femoropopliteal arterial occlusions. Methods: Baseline characteristics and outcomes of 52 patients (40 men; mean age 65.6±9.7 years) with superficial femoral artery (SFA) occlusions in 61 limbs (mean occlusion length 22.7±9.9 cm) treated with subintimal angioplasty and primary stenting were compared with a 54-patient control group (46 men; mean age 64.8±8.2 years) from our registry database who had intraluminal angioplasty with stenting in 60 limbs (mean occlusion length 22.0±8.5 cm). Results: All baseline clinical and angiographic characteristics showed no differences. In all patients, at least 1 self-expanding nitinol stent was implanted. Subintimal angioplasty was successful in 58 (95.1%) of 61 limbs, whereas technical success for the conventional approach was 86.7% (52/60 limbs; p=0.11). In both groups, there were no major complications requiring surgery. Primary patency at 12 months for successful cases was 76.4% for subintimal angioplasty and 59.2% for conventional angioplasty (p=0.06); on an intention-to-treat basis, including technical failures, the rates were 72.4% and 50.9%, respectively (p=0.02). Conclusion: Subintimal angioplasty combined with stenting was feasible, with a high technical success rate and better short and midterm results for revascularization of long femoropopliteal occlusions than the conventional intraluminal approach.

Stent-graft treatment of infected aortic and arterial aneurysms.

Purpose: To evaluate the feasibility and effectiveness of endovascular stent-graft repair of infected aortic and arterial aneurysms. Methods: Eight patients (5 men; mean age 56.6 years, range 30–85) with infected saccular aneurysms in the brachiocephalic artery (n=1), proximal descending thoracic aorta (n=1), infrarenal abdominal aorta (n=3), common iliac artery (n=1), and common femoral artery (n=2) were treated with stent-graft placement and intravenous antibiotic treatment for at least 6 weeks followed by case-specific administration of oral suppressive antibiotics. All patients were considered to be in the high-surgical-risk group. Results: Exclusion of the infected aneurysm was successful in all patients. However, 2 patients died within 30 days of uncontrolled sepsis, and 1 patient died at 6 months after rupture of a persistently infected aneurysm (37% mortality rate). Over a follow-up that ranged to 8 years, the 5 survivors showed complete resolution of the infected aneurysms; no stent-graft infection was observed during follow-up. Conclusion: The acceptable technical and clinical success of endovascular aneurysm repair makes this a promising treatment for infected aortic and arterial aneurysms. However, it is crucial that the infection is treated adequately prior to stent-graft placement.

Quantification of regional calcium burden in chronic total occlusion by 64-slice multi-detector computed tomography and procedural outcomes of percutaneous coronary intervention

BACKGROUND One of the most important reasons for failure of percutaneous coronary intervention (PCI) in chronic total occlusion (CTO) is calcified plaque, which either prevents passage of guide wire or ruptures after balloon inflation. We sought to evaluate whether quantified calcium contents of CTO on multi-detector computed tomography (MDCT) correlate with immediate procedural outcomes. METHODS Sixty-four patients with 72 CTO lesions who underwent 64-slice MDCT prior to PCI were investigated. The lesions were divided into 2 groups according to procedural outcomes (55 lesions with PCI-success group, 17 lesions with PCI-failure group). Clinical, angiographic and MDCT parameters, including regional calcium volume (RCaV), regional calcium score (RCaS), regional calcium equivalent mass (RCaEq), and relative calcium area at the most calcified cross section of CTO (%CaS/CSA), were compared between the two groups. RESULTS The duration of CTO was shorter in PCI-success group than PCI-failure group (7.16 ± 10.5 vs 15.59 ± 14.92 months, p=0.011), and the procedural success rate was 76.3%. Regional calcium-related parameters (RCaV 52.86 ± 58.39 vs 7.26 ± 15.27 mm(3), p<0.001; RCaS 72.71 ± 78.4 vs 9.66 ± 20.2, p<0.001; RCaEq 12.58 ± 12.97 vs 1.84 ± 3.716 mgCaHA, p<0.001; %CaS/CSA 53.9 ± 20.3 vs 30.4 ± 17.1%, p=0.009) in the occluded segment were higher and the occlusion length was longer (37.44 ± 27.48 vs 22.00 ± 18.04 mm, p<0.021) in PCI-failure group compared to PCI-success group. Multivariate regression analysis showed that only %CaS/CSA was a significant determinant of PCI-failure. CONCLUSIONS Precise quantification of regional calcification and measurement of the occluded segment by high resolution MDCT can deliver important information for predicting procedural outcomes in PCI of CTO.

The clopidogrel resistance can be attenuated with triple antiplatelet therapy in patients undergoing drug-eluting stents implantation

BACKGROUND Triple antiplatelet therapy may have a beneficial effect on prevention of thrombotic complication in patients undergoing coronary stenting. We investigated the prevalence of aspirin and clopidogrel resistance in patients treated with dual and triple antiplatelet regimen after percutaneous coronary intervention (PCI) with drug-eluting stents (DES). METHODS A total of 400 consecutive patients underwent successful PCI with DES were randomly assigned to therapy with dual antiplatelet regimens (aspirin plus clopidogrel, Group I, n = 200) and triple antiplatelet regimens (aspirin plus clopidogrel plus cilostazol, Group II, n = 200) At two weeks after PCI, aspirin and clopidogrel resistance were assayed in 379 patients (Group I, n = 186; Group II, n = 193) by using the VerifyNow System. RESULTS In Group I, 21 (11.3%) patients had aspirin resistance and 74 (40.0%) had clopidogrel resistance. In Group II, 19 (9.8%) were resistant to aspirin and 38 (19.7%) to clopidogrel. The aspirin reaction unit (ARU) was not significantly different between groups (448+/-67 vs. 439+/-64, P = 0.200), but the percent inhibition of clopidogrel was higher in Group II (41.4+/-24.3%,) comparing with that of Group I (26.5+/-18.7%, P < 0.001). CONCLUSION With triple antiplatelet therapy, the prevalence of clopidogrel resistance can be attenuated in patients undergoing PCI with DES.

The prevalence and clinical predictors of atherosclerotic renal artery stenosis in patients undergoing coronary angiography

Renal artery stenosis is an important cause of secondary hypertension as well as ischemic nephropathy. The purpose of this study was to determine the clinical predictors in patients with renal artery stenosis in a population referred for coronary angiography. From March 1998 to July 1999, 1459 patients undergoing coronary angiography for various indications were routinely screened for renal artery stenosis by undergoing abdominal aortography. Coronary angiography, carotid angiography, and abdominal aortography was performed via either the radial or the femoral approach. The data were analyzed retrospectively. Out of 1459 patients undergoing abdominal aortography, 158 (10.8%) were found to have significant renal artery stenosis with 24 of the patients having bilateral stenosis. Significant coronary artery diseases were found in 994 of the 1459 study population (68.1%), with 134 (13.5%) of these patients having concomitant renal artery stenosis. Multivariate logistic regression showed that extracranial carotid artery stenosis odds ratio [(OR) 4.89 (95% confidence interval 2.57–9.33), P < 0.001], peripheral artery disease [OR 4.64 (2.65–9.33), P < 0.001], renal insufficiency [OR 2.68 (1.43–5.02), P = 0.002], significant coronary artery disease [OR 2.01 (1.12–3.59), P = 0.019], hypercholesterolemia [OR 1.92 (1.07–3.43), P = 0.028], hypertension [OR 1.85 (1.16–2.95), P = 0.010], and old age (>60 years) [OR 1.64 (1.01–2.64), P = 0.044] were significant clinical predictors of renovascular disease. The prevalence of indolent atherosclerotic renal artery stenosis is relatively high in selected groups of patients with high clincial risk factors for this underdiagnosed disease. Renal artery stenosis should be highly suspected in patients who have these risk factors because early detection of this disease may reverse the progression to chronic renal failure and end-stage renal disease.

Usefulness of cilostazol versus ticlopidine in coronary artery stenting

A combination of ticlopidine and aspirin has been accepted as the standard antithrombotic regimen after coronary stenting. However, ticlopidine poses serious side effects such as neutropenia or thrombocytopenia. Cilostazol, a cyclic adenosine monophosphate phosphodiesterase inhibitor, is a novel antiplatelet agent with vasodilatory properties. We compared the efficacy and safety of cilostazol plus aspirin (C+A) with ticlopidine plus aspirin (T+A) in elective coronary stenting. Three hundred patients were randomly assigned to receive C+A or T+A 2 days before stenting. The primary end point was a composite of angiographic stent thrombosis, or major cardiac events (death, myocardial infarction, bypass surgery, repeat intervention) at 30 days. The secondary end points were bleeding vascular complications, neutropenia, thrombocytopenia, or side effects requiring discontinuation of the drugs at 30 days. The primary end point was reached in 1.4% in the C+A group and 2.0% in the T+A group (p = 1.0). The rate of bleeding vascular complications was 1.4% in the C+A group and 2.0% in the T+A group (p = 1.0). The rate of drug-related side effects was not statistically different between the 2 groups but slightly higher in the T+A group than in the C+A group (2.7% vs 0.7%, p = 0.37). However, neutropenia was seen in 2 patients only in the T+A group. As a poststenting antithrombotic, C+A is as effective as T+A in preventing major cardiac events including stent thrombosis, and safer in that it does not cause neutropenia despite the fact that there is no statistical difference in the incidence of adverse effects and complications.

Intermediate to long-term outcomes of endoluminal stent-graft repair in patients with chronic type B aortic dissection.

Purpose: To assess mid- to long-term clinical results of stent-graft repair in patients with type B aortic dissection. Methods: Retrospective analysis was done on 72 patients (47 men; mean age 55±12 years) who were diagnosed with chronic type B aortic dissection and underwent stent-graft repair from June 1994 to December 2007. Two types of stent-grafts were employed. Prior to 2000, a custom-designed stent-graft composed of self-expanding Z-type stainless steel stents covered with woven polytetrafluoroethylene material was used. Thereafter, a separate-type (modular) manufactured stent-graft was used, consisting of proximal and distal nitinol stents with an unsupported Dacron tube graft in between; the unsupported graft was stented after deployment. Results: Procedural success (completion of the stent-graft deployment at the target area without device failure) was obtained in 97% (70/72). The 2 failures were due to stent migration and tortuous anatomy, respectively. There were persistent type I endoleaks in 6 cases for a clinical success (entry tear exclusion) of 88% (64/72). There was no immediate postprocedural mortality or paraplegia. There was unintended partial left subclavian artery occlusion in 1 case, as well as postprocedural transient renal failure in 1 patient and 2 access-site pseudoaneurysms. Median follow-up was 43 months (range 5–97, mean 64.4±38.8) in 61 patients (3 patients lost to follow-up). Five patients died, 1 of probable aortic rupture in the setting of residual type I endoleak. Overall clinical success (no death, conversion, or endoleak) was achieved in 84% (47/56); of these, 35 (74%) showed complete resolution of the thoracic false lumen, while the other 12 (26%) had a decrease in false lumen diameter. Conclusions: Intermediate to long-term results of stent-graft implantation in patients with chronic type B aortic dissection seem acceptable and may justify the use of this minimally invasive approach as first line therapy in these patients.