[Show abstract][Hide abstract] ABSTRACT: We angioscopically compared paclitaxel-eluting stents (PES) and sirolimus-eluting stents (SES) to explore differences in arterial healing.
Drug-eluting stents may demonstrate different arterial healing processes.
Angioscopy was performed 9 +/- 2 months after 30 PES and 36 SES were implanted initially in the native coronary artery. Heterogeneity of the neointimal coverage (NIC) as well as the dominant grade was examined. Neointimal coverage was defined as follows: grade 0 = fully visible struts; grade 1 = struts bulged into the lumen, but covered; grade 2 = embedded, but translucent struts; grade 3 = invisible struts. Heterogeneity was judged when the NIC grade variation >or=1. Thrombi and yellow plaques (YP) were also explored.
In-stent late loss (0.44 +/- 0.44 mm vs. 0.13 +/- 0.33 mm; p < 0.0001) and dominant NIC grade (1.8 +/- 1.1 vs. 1.3 +/- 0.7; p = 0.02) were greater in PES than in SES. Of PES, 48% showed the heterogeneity of 1 grade; 26% showed that of 2 grades. Of SES, 53% showed homogeneous coverage; the remaining SES showed the heterogeneity of 1 grade; and 72% showed dominant grade 1. Thrombi were more common in PES than in SES (43% vs. 19%; p = 0.04). Both stents commonly revealed YP (83% vs. 78%; p = 0.76).
NIC was more heterogeneous in PES, associated with a higher incidence of thrombi. Homogeneous NIC may be an important factor for competent arterial healing.
[Show abstract][Hide abstract] ABSTRACT: Post-systolic shortening (PSS) is a sensitive indicator of myocardial ischemia.
We have developed a tissue Doppler imaging technique that portrays PSS, and whether PSS correlates with coronary artery disease (CAD) was investigated in 186 patients presenting with chest pain and normal echocardiograms. Delays of the displacement peaks from end-systole were calculated in the apical views and displayed from green (0 ms) to red (>or=100 ms): detection of diastolic abnormality by dyssynchrony imaging (DADI). CAD was judged positive by DADI when the left ventricular segments were color-coded red. Patients subsequently underwent thallium-201 myocardial perfusion single-photon emission computed tomography (n=150), coronary angiography (CAG, n=74), or both (n=37). CAD(-) was defined as negative scintigraphy test and/or no significant coronary artery stenosis by CAG. In 43 patients (23%), CAD(+) was confirmed by CAG as >75% diameter stenosis. DADI predicted CAD with sensitivity of 60%, specificity of 75%, predictive accuracy of 72%, positive predictive value of 42%, and negative predictive value of 86%. Among 74 patients who underwent CAG, sensitivity was best for the left anterior descending artery.
DADI detected the regional diastolic abnormality, which correlated with the presence of CAD in patients presenting with visibly normal wall motion.
[Show abstract][Hide abstract] ABSTRACT: Despite the recent development of endovascular therapy (EVT), a high incidence of restenosis remains as an unsolved issue in patients presenting with femoropopliteal lesions. We investigated whether cilostazol reduces restenosis after successful EVT for de novo femoropopliteal lesions.
This study was designed as a prospective, randomized, open-label, blinded end point study in a single institution. Between March 2004 and June 2005, we randomized 127 patients who were successfully treated with EVT for de novo femoropopliteal lesions to receive cilostazol (200 mg/d, n = 63) or ticlopidine (200 mg/d, n = 64) in addition to aspirin (100 mg/d). Antiplatelet medications were started at least 1 week before EVT and were continued until the end of follow-up. Patency was defined by duplex ultrasound imaging with peak systolic velocity ratio >2.4.
There were no significant differences in the patients and lesion characteristics. Sixteen patients dropped out of the study protocol, six of whom were withdrawn due to adverse drug effects (cilostazol, n = 5; ticlopidine, n = 1; P = .09). Ten patients died (cilostazol, n = 4; ticlopidine, n = 6; P = .53) during the follow-up period. Patency rates at 12, 24, and 36 months were 87%, 82%, and 73% in the cilostazol group and 65%, 60%, and 51% in ticlopidine group by intention-to-treat analysis (P = .013) and were 87%, 82%, and 73% in the cilostazol group and 64%, 57%, and 48% in the ticlopidine group (P = .0088) by as-treated analysis. Freedom from target lesion revascularization and all adverse events (restenosis, amputation, and death) was significantly higher in cilostazol group than in ticlopidine group (P = .036, P = .031). No acute, subacute, or chronic thrombotic occlusion was encountered, and bleeding complication rates were similar between the two groups.
Cilostazol significantly reduces restenosis after EVT in femoropopliteal lesions.
Journal of Vascular Surgery 07/2008; 48(1):144-9. · 2.88 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Fibromuscular dysplasia (FMD) is a nonatherosclerotic, noninflammatory vascular disease that mostly affects the renal and internal carotid arteries, rarely complicating lower limbs. We report a case of FMD complicating critical limb ischemia due to the obstruction of below the knee arteries, diagnosed and treated with the support of skin perfusion pressure (SPP) measurement. Initial angiogram revealed the anterior tibial artery (ATA) was subtotally occluded showing a "strings of beads" pattern, which is typical of the arteries affected by FMD. SPP guided endovascular therapy was successful for ATA lesions. Intractable rest pain subsequently disappeared and the ulcer was completely healed without amputation.
Journal of Vascular Surgery 11/2007; 46(4):803-7. · 2.88 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The time course of neointimal formation after stent implantation has not been studied extensively by angioscopy in the drug-eluting stent era.
Serial angioscopic findings at first follow-up (3.6+/-1.1 months), second follow-up (10.5+/-1.6 months), and third follow-up (21.2+/-2.2 months) after stent implantation were compared between sirolimus-eluting stents (SES, n=17) and bare-metal stents (BMS, n=11). Neointimal coverage, thrombus, and presence of yellow plaques underneath the stents were assessed. Neointimal coverage was graded as follows: grade 0, stent struts were fully visible; grade 1, struts bulged into the lumen, although they were covered; grade 2, struts were embedded by the neointima but were seen translucently; or grade 3, struts were fully embedded and invisible. Neointimal coverage was remarkably different between SES and BMS at each follow-up point. Neointimal coverage grade was 1.1+/-0.5 in SES versus 2.9+/-0.3 in BMS at the first follow-up (P<0.0001), 1.1+/-0.5 in SES versus 3.0+/-0.0 in BMS (P<0.0001) at the second follow-up, and 1.3+/-0.5 in SES versus 3.0+/-0.0 in BMS at the third follow-up (P=0.0009). No significant serial changes in coverage grade were noted in the BMS group, whereas coverage grade slightly but significantly increased at the third follow-up in the SES group (P<0.05). Thrombi were detected in 4 SES: a red thrombus was seen from the first to the third follow-up in 2; another was detected only at the third follow-up; and the fourth was seen at the first follow-up but disappeared at the second follow-up, associated with a new white thrombus despite dual antiplatelet therapy. Yellow plaques had disappeared by the time of the second follow-up in BMS. In contrast, yellow plaques were exposed in 71% of SES at the first follow-up and remained exposed until the third follow-up. Neointimal coverage grades correlated with thrombi (P=0.002) and with yellow plaques (P<0.0001).
Serial angioscopic findings up to 2 years after SES implantation were markedly different from those after BMS. Neointimal coverage was completed by 3 to 6 months in BMS. In contrast, SES demonstrated the presence of thrombi and yellow plaques even as much as 2 years after implantation.
[Show abstract][Hide abstract] ABSTRACT: A 44-year-old male was admitted to our hospital for dyspnea, associated with severe pulmonary hypertension. The patient fell into a shock state on the next day. Hemodynamic measurements revealed high output heart failure with low peripheral vascular resistance. We suspected shoshin beriberi, a fulminant form of cardiac beriberi, by ruling out other common causes of pulmonary hypertension. The rapid recovery after intravenous thiamine administration and the patient's history of improper diet strongly supported the diagnosis. The present case of shoshin beriberi complicating severe pulmonary hypertension shows that history taking is important in elucidating the etiology and selecting the correct treatment.
Journal of Cardiology 07/2007; 49(6):361-5. · 2.30 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A positive myocardial velocity during isovolumic relaxation phase (V(IR)) detected by spectral tissue Doppler imaging has been shown to indicate ischemic myocardium. We sought to examine the diagnostic value of positive V(IR) for detecting coronary artery disease (CAD) in patients with chest pain and apparently normal left ventricular contraction.
A total of 138 patients (74 men, age 69 +/- 8 years) underwent spectral Doppler tissue imaging measurements at the annular and mid left ventricular levels in the apical 4- and 2-chamber views (8 points/patient) at rest in addition to standard echocardiography. Subsequently, patients underwent thallium-201 myocardial perfusion single photon emission computed tomography (n = 98) and/or coronary angiography (n = 60). The duration of positive V(IR) was also assessed. CAD was diagnosed by having more than 75% diameter stenosis in coronary angiography.
CAD was present in 41 patients (30%). The duration of positive V(IR) was distributed from 0 to 280 milliseconds with the median value of 100 milliseconds. Presence of positive V(IR) predicted CAD with sensitivity of 80% and specificity of 61%.
Positive V(IR) detected by spectral tissue Doppler imaging is a useful indicator of CAD in patients with apparently normal left ventricular contraction and chest pain.
Journal of the American Society of Echocardiography: official publication of the American Society of Echocardiography 03/2007; 20(2):158-64. · 2.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Stent fracture has emerged as a new problem in the percutaneous transluminal angioplasty of the superficial femoral artery (SFA). The aim of our study was to delineate the factors influencing nitinol stent fracture in the SFA. Forty consecutive patients with peripheral artery disease who underwent rescue stenting with a nitinol stent (Luminexx, Bard) in the SFA were enrolled between May 2004 and January 2005. Follow-up angiography was performed 13.6+/-1.0 months later to detect stent fracture. Stent fracture occurred in 11 patients (28%). Lesion length>100 mm, the number of stents used, the lesion involving the distal SFA, chronic total occlusion, and walking>5,000 steps per day were more frequently observed in those with stent fracture than in those without fracture. Of these variables, walking>5,000 steps per day was the strongest independent determinant associated with stent fracture by discriminant analysis (p=0.0027). Vigorous exercise adversely affects stent fracture in patients implanted with a nitinol stent in the SFA.
The American Journal of Cardiology 08/2006; 98(2):272-4. · 3.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The nature of the vessel lumen following vascular brachytherapy (VBT) has not been extensively explored in the clinical setting.
By using angioscopy, 33 stents treated with percutaneous balloon angioplasty with or without VBT for in-stent restenosis after 8.9 +/- 2.1 months of the treatment were followed (VBT =14 lesions; control =19 lesions). Neointimal coverage, stent attachment, and the presence of red or white thrombi were factors that were assessed. The majority of the stents (74%) were fully covered with non-transparent neointima in the control group. In contrast, stent struts were clearly seen in 57% lesions with VBT. The absence of neointima with glittering stent struts were only seen in 29% of lesions in VBT (p = 0.03). Incomplete stent attachment was not detected in the controls, whereas 14% were in VBT (p = 0.17). Red thrombi were observed in 14% with VBT and in 16% in controls, which showed that there was a similar incidence regardless of the treatment. Neither exposure of stent struts (p = 0.5) nor incomplete stent attachment (p = 1.0) was related to thrombi.
The exposure of stent struts and incomplete stent attachment were occasionally observed by angioscopy even 9 months after VBT for the treatment of in-stent restenosis.
[Show abstract][Hide abstract] ABSTRACT: Although the elevation of circulating plasma matrix metalloproteinase (MMP)-9 levels in patients with acute myocardial infarction (AMI) has been documented, the origin of MMP-9 remains unclear.
Plasma MMP-9 levels in both the peripheral circulation and coronary arteries were measured in patients with AMI (n=23) and with stable angina pectoris (SAP, n=10) during percutaneous coronary intervention (PCI) with a distal protection device. Blood samples were collected from the femoral artery (FA) and the coronary artery before (Initial) and after (Second) dilation of the culprit lesion. Coronary sinus blood samples were obtained immediately after PCI (n=7). Coronary artery plaque fragments were aspirated in patients with AMI (n=20) and compared with those from patients with SAP who underwent directional atherectomy (n=10). MMP-9 levels in Initial and Second were significantly higher in patients with AMI than in patients with SAP (p<0.01). In AMI patients MMP-9 levels were significantly higher in Initial than in the FA (p<0.05), and were further increased in Second (p<0.0001), whereas those in the coronary sinus were similar to the FA. Immunohistochemistry revealed augmented MMP-9 expression in the coronary artery plaque fragments from AMI patients.
MMP-9 is mainly released into the coronary circulation from the coronary artery plaque in patients with AMI.
[Show abstract][Hide abstract] ABSTRACT: Although percutaneous transluminal angioplasty (PTA) is being widely used for the treatment of stenosis of peripheral arteries, the high in-stent restenosis rate (50-60%) in the femoropopliteal artery still remains an unsolved issue. Cilostazol is a unique antiplatelet drug that has vasodilatory effects and inhibits smooth muscle cell proliferation.
A total of 141 consecutive patients scheduled for PTA in the femoropopliteal artery between September 1999 and April 2004 were retrospectively analyzed for the use of cilostazol. Target lesion revascularization (TLR) was defined as repeated PTA in patients who had a recurrence of symptoms with diameter stenosis >50% by angiography. Patient and lesion characteristics were similar between the cilostazol (+) and cilostazol (-) groups. Use of other medications was similar between the groups, except for ticlopidine, which was more frequently used in the cilostazol (-) than in the cilostazol (+) group (15% vs 61%, p<0.01). TLR was significantly reduced in the cilostazol (+) group (12% [8/68] vs 32% [23/73], p<0.01).
Although this study was retrospective and nonrandomized, the results suggest that cilostazol reduces TLR after PTA in the femoropopliteal artery.
[Show abstract][Hide abstract] ABSTRACT: Plaque characterization by intravascular ultrasound (IVUS) before percutaneous coronary intervention (PCI) was evaluated in 81 consecutive patients with acute myocardial infarction (AMI) to establish if IVUS can predict the occurrence of the 'no-reflow' phenomenon. Angiographic no-reflow was defined as TIMI flow grade 1 or 2 without any mechanical obstruction in the epicardial artery. Patients were divided into 2 groups according to the post-PCI angiograms: normal flow (group R, n=60) and no-reflow (group NR, n=21). Although the incidence of either soft or noncalcified plaque was not statistically different between the groups, positive vessel remodeling was more frequent in group NR than in group R (57.1% vs 31.6%, p<0.05). Lipid core was also more frequently found in group NR than in group R (61.9% vs 25.0%, p<0.01). Positively remodeled vessels with lipid-rich plaques as characterized by IVUS before PCI predicted the occurrence of angiographic no reflow with a sensitivity of 43% and a specificity of 60%.