Ryuji Otani

Japanese Red Cross, Edo, Tōkyō, Japan

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Publications (8)13.52 Total impact

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    ABSTRACT: Perfusion-metabolism mismatch in the subacute phase using thallium-201/radio iodinated beta-methyl-p-iodophenyl pentadecanoic acid (T1/BMIPP) dual scintigraphy is an indicator of viable myocardium in acute myocardial infarction. This study investigated early prediction of myocardial salvage from the T1/BMIPP mismatch and coronary flow velocity (CFV) patterns in patients with acute myocardial infarction. Thirty three patients with first anterior wall myocardial infarction underwent primary coronary angioplasty and achieved reflow within 8 hr of onset. By using a Doppler guide wire, CFV patterns were assessed immediately after primary coronary angioplasty. T1/BMIPP dual scintigraphy was performed within 3 days after reperfusion. The extent of discordance in severity score was defined as the T1/BMIPP mismatch score. Regression analysis showed dual scintigraphy mismatch score correlated well with deceleration time of diastolic flow velocity (r = 0.54, p < 0.01). Mismatch score was greater in the non-early systolic reversal flow group than in the early systolic reversal flow group (5.5 +/- 3.3 vs 1.9 +/- 2.1, respectively, p < 0.01). Changes in CFV patterns correlated well with T1/BMIPP mismatch score. CFV pattern immediately after reperfusion is useful for early prediction of myocardial salvage.
    No preview · Article · Apr 2007 · Journal of Cardiology
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    ABSTRACT: The goal of this study was to investigate the efficacy of stenting after rotational atherectomy (rotastent) for ostial LAD and ostial LCX stenosis in patients with diabetes. Previous studies have demonstrated that rotastent for non-aorto ostial stenoses can be performed safely with high clinical success rate. However, in diabetic patients, long-term results of rotastent for ostial stenoses are still unknown. A series of 70 patients with de novo non-aorto ostial stenosis who underwent successful elective stenting after rotational atherectomy were the subject of this study. Clinical, angiographic, and procedural characteristics, as well as acute and chronic results were obtained for all patients. There were no significant differences between diabetic versus non-diabetic patients in terms of baseline clinical characteristics, lesion characteristics, and procedural factors. The restenosis rate of diabetic patients was significantly higher than that of non-diabetic patients as assessed by the follow-up angiogram (53% versus 28%, respectively; p < 0.05). The rate of lesion progression which meant the development of new left main or non-treated artery-ostial narrowing was significantly higher in diabetic patients at follow-up angiography (23% versus 5%; p < 0.05 compared to non-diabetic patients). By use of multiple regression analysis, diabetes mellitus was identified as an independent predictor of restenosis and lesion progression. These results suggest that diabetic patients are more likely to have not only higher rates of restenosis but also development of new left main narrowing or non-treated artery ostial narrowing compared to non-diabetic patients.
    No preview · Article · Jan 2005 · The Journal of invasive cardiology

  • No preview · Conference Paper · Jan 2005
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    ABSTRACT: Background: The purpose of this study was to identify clinical and anatomical characteristics which may not benefit from RESCUE™ catheter in patients with acute myocardial infarction (AMI). Methods: Sixty-six consecutive AMI patients, who had extensive thrombi in the right coronary artery (RCA), were enrolled in this study. We measured Thrombolysis in Myocardial Infarction (TIMI) frame count (TFC) immediately after performing RESCUE™ catheter and defined unsuccessful reperfusion as TFC≧ 40. The patients were divided into two groups: TFC< 40 group (n=55) and TFC≧40 group(n=11). The two groups were compared and multivariate and multivariate analyses were performed to identify clinical and anatomical factors in predicting unsuccessful reperfusion. Results: In a multivariate model, large vessel diameter and late recanalization were the independent predictors for unsuccessful reperfusion (p<0.05). Conclusion: Large vessel diameter and late recanalization are independently associated with unsuccessful reperfusion immediately after RESCUE™ catheter in patients with AMI related to RCA.
    No preview · Article · Aug 2003 · Kokyu to junkan. Respiration & circulation
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    ABSTRACT: One of the major limitations in coronary stenting is in-stent restenosis. This study was aimed to identify clinical, angiographic, and procedural factors that may be related to recurrent in-stent restenosis. We analyzed consecutive 197 patients who underwent coronary stenting. Follow-up angiography was available in 170 patients and repeat balloon angioplasty was performed for in-stent restenosis. These patients were subdivided into 3 groups: group A consisted of 100 patients that were never restenosed, group B had 49 patients restenosed once, and in group C were 21 patients restenosed more than twice. Group C was more often female (48%) and included diabetes mellitus patients (52%). Lesion location, reference vessel size and diameter stenosis were similar for all groups. However, the incidence of calcified lesions tended to be higher (50% vs. 29%; p = 0.07), and lesion length was longer in group C than in group A (11.9+/- 5.4 mm vs. 9.0+/- 3.9 mm; p < 0.01). Diameter stenosis after predilation as well as after stenting was significantly higher in group C than in group A (50+/- 10% vs 39+/- 10%; p < 0.01, 32+/- 8% vs. 19+/- 10%; p < 0.01). The incidence of diffuse type of in-stent restenosis was significantly higher in group C than in group B (62% vs. 14%; p < 0.01). Multivariate logistic regression analysis identified diameter stenosis after stenting (p = 0.0022), female (p = 0.0135), and diameter stenosis after predilatation (p = 0.0233) as the significant correlate of recurrent in-stent restenosis. In conclusion, the major recurrent in-stent restenosis predictors identified included female gender, final diameter stenosis, and diameter stenosis after predilatation.
    No preview · Article · Apr 2002 · The Journal of invasive cardiology
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    ABSTRACT: We examined the efficacy of rotational atherectomy for diffuse coronary artery disease in diabetic patients and found that the restenosis rate of diabetic patients after rotational atherectomy was significantly higher than that of nondiabetic patients, and the lesion length between preprocedure and follow-up angiograms in the diabetic patients did not shorten as much as those of the nondiabetic patients. These data suggest that rotational atherectomy for diffuse coronary artery disease is less effective for preventing restenosis in diabetic compared with nondiabetic patients.
    No preview · Article · May 2001 · The American Journal of Cardiology
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    ABSTRACT: The long-term outcome after coronary stent placement in restenotic lesions after balloon angioplasty (percutaneous transluminal coronary angioplasty: PTCA)may be less favorable compared to stent treatment of de novo lesions, but the role of stents in restenotic lesions after 2 prior PTCA procedures is unknown. Elective Palmaz-Schatz stent placement was performed in 124 consecutive patients. Stents were placed in 70 patients(56%) in the native coronary arteries for de novo lesions(de novo group), in 33 patients (27%)for restenotic lesions after one prior PTCA(restenosis group), and 21 patients(17%)for restenotic lesions after 2 prior PTCA(second restenosis group). The 3 groups were well matched with respect to lesion type, lesion length, and reference diameter. Stent size was similar in the 3 groups. Follow-up angiograms taken about 6 months after stenting were available for all patients. The restenosis rate after stenting was similar for the de novo group and restenosis group(19% vs 27%, NS). The second restenosis group tended to have a higher restenosis rate after stenting than the de novo group(38% vs 19%, p = 0.06). The frequency of diffuse type in-stent restenosis of the second restenosis group tended to be higher than that of the de novo group(63% vs 13%, p = 0.08). Our results suggest that the restenosis rate after stenting was higher in patients with repeated restenosis. Therefore, other therapeutic methods should be considered.
    No preview · Article · Dec 1999 · Journal of Cardiology
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    ABSTRACT: Intracoronary stenting reduces the restenosis rate after percutaneous transluminal coronary angioplasty (PTCA). However, restenosis still occurs in 20% to 30% of patients after stenting. Management of in-stent restenosis has become a significant challenge in interventional cardiology. The efficacy of re-PTCA with a larger balloon was investigated for restenosis following Palmaz-Schatz stenting. Clinical and angiographic results were compared in 46 consecutive patients with in-stent restenosis after one Palmaz-Schatz stenting. Twenty patients underwent redilation with a slightly larger balloon than used at the stenting (Large group) and 26 underwent redilation with the same size balloon as at the stenting (Control group). The clinical factors, lesion characteristics, lesion length, reference diameter and minimal luminal diameter at re-PTCA for the in-stent restenosis did not differ significantly between the 2 groups. Minimal luminal diameter of the Large group after re-PTCA was significantly larger than that of the Control group (3.1 +/- 0.2 vs 2.9 +/- 1.2 mm, p < 0.05). Follow-up angiography showed that the minimal luminal diameter of the Large group was significantly larger (2.1 +/- 0.6 vs 1.7 +/- 0.6 mm, p < 0.05) and the re-restenosis rate of Large group tended to be lower than that of the Control group (15% vs 38%, p = 0.07). Re-PTCA for in-stent restenosis with a slightly larger balloon than used at the stenting reduces the re-restenosis rate.
    No preview · Article · Aug 1999 · Journal of Cardiology