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Dive into the research topics where Yoichi Nozaki is active.

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Featured researches published by Yoichi Nozaki.


Circulation | 2009

Three-Year Outcomes After Sirolimus-Eluting Stent Implantation for Unprotected Left Main Coronary Artery Disease Insights From the j-Cypher Registry

Mamoru Toyofuku; Takeshi Kimura; Takeshi Morimoto; Yasuhiko Hayashi; Hiroaki Ueda; Kazuya Kawai; Yoichi Nozaki; Shinichi Hiramatsu; Akira Miura; Yoshiaki Yokoi; Shinichiro Toyoshima; Hitoshi Nakashima; Kazuo Haze; Masaru Tanaka; Shunsuke Take; Shigeru Saito; Takaaki Isshiki; Kazuaki Mitsudo

Background— Long-term outcomes after stenting of an unprotected left main coronary artery (ULMCA) with drug-eluting stents have not been addressed adequately despite the growing popularity of this procedure. Methods and Results— j-Cypher is a multicenter prospective registry of consecutive patients undergoing sirolimus-eluting stent implantation in Japan. Among 12 824 patients enrolled in the j-Cypher registry, the unadjusted mortality rate at 3 years was significantly higher in patients with ULMCA stenting (n=582) than in patients without ULMCA stenting (n=12 242; 14.6% versus 9.2%, respectively; P<0.0001); however, there was no significant difference between the 2 groups in the adjusted risk of death (hazard ratio 1.23, 95% confidence interval 0.95 to 1.60, P=0.12). Among 476 patients whose ULMCA lesions were treated exclusively with a sirolimus-eluting stent, patients with ostial/shaft lesions (n=96) compared with those with bifurcation lesions (n=380) had a significantly lower rate of target-lesion revascularization for the ULMCA lesions (3.6% versus 17.1%, P=0.005), with similar cardiac death rates at 3 years (9.8% versus 7.6%, P=0.41). Among patients with bifurcation lesions, patients with stenting of both the main and side branches (n=119) had significantly higher rates of cardiac death (12.2% versus 5.5%; P=0.02) and target-lesion revascularization (30.9% versus 11.1%; P<0.0001) than those with main-branch stenting alone (n=261). Conclusions— The higher unadjusted mortality rate of patients undergoing ULMCA stenting with a sirolimus-eluting stent did not appear to be related to ULMCA treatment itself but rather to the patients’ high-risk profile. Although long-term outcomes in patients with ostial/shaft ULMCA lesions were favorable, outcomes in patients with bifurcation lesions treated with stenting of both the main and side branches appeared unacceptable.


Eurointervention | 2013

Contemporary retrograde approach for the recanalisation of coronary chronic total occlusion: on behalf of the Japanese Retrograde Summit Group.

Masahisa Yamane; Makoto Muto; Tetsuo Matsubara; Shigeru Nakamura; Toshiya Muramatsu; Akitsugu Oida; Yasumi Igarashi; Yoichi Nozaki; Mikihiro Kijima; Etsuo Tuschikane

AIMS The retrograde approach to CTO is promising, but questions remain with regard to its wider application and the potential risks. This study evaluated the feasibility and efficacy of retrograde recanalisation of chronic total occlusion (CTO) of the coronary arteries. METHODS AND RESULTS A total of 378 consecutive patients (previously failed PCI 32.0%) who enrolled in 27 institutions in Japan underwent retrograde recanalisation for CTO. We analysed the data on lesion characteristics, procedural materials, technique used, complications and clinical outcomes. Successful retrograde recanalisation was achieved in 70.4% and the overall procedural success was 83.6%. Collateral crossing was achieved via a septal route in 68.9%, epicardial in 27.2% and bypass grafts in 2.6%, respectively. The retrograde approach was completed with implementation of reverse CART in 42.5%, direct wire crossing in 23.1%, bilateral wiring in 22.7%, and CART in 11.7%. Major and minor collateral injuries and coronary perforations were noted in 1.3%, 10.3% and 2.9% of cases, respectively. Stroke occurred in 0.3%, QWMI and emergency PCI in 0.3% of patients with successful recanalisation. CONCLUSIONS Wider application of retrograde CTO PCI achieved a high rate of success in recanalisation with an acceptable rate of complications in Japan.


European Journal of Nuclear Medicine and Molecular Imaging | 1998

Use of 123I-BMIPP single-photon emission tomography to estimate areas at risk following successful revascularization in patients with acute myocardial infarction

Yuko Kawai; Eriko Tsukamoto; Yoichi Nozaki; Koh Kishino; Tetsuro Kohya; Nagara Tamaki

Abstract. Previous studies have indicated that iodine-123 labelled β-methyliodophenyl pentadecanoic acid (BMIPP), an iodinated fatty acid analogue, can identify persistent alteration of fatty acid metabolism after restoration of blood flow. To assess whether fatty acid imaging can delineate areas at risk following successful revascularization in patients with acute myocardial infarction (AMI), BMIPP findings at 1 week post AMI were compared with perfusion imaging before and after revascularization therapy. Sixty-five patients with AMI underwent technetium-99m tetrofosmin single-photon emission tomography (SPET) before m (TF0) and 1 week (TF1) after successful revascularization therapy. BMIPP SPET was also performed under a fasting state at 1 week (BM1) post AMI. The extent scores were calculated from the defect scores in 20 segments. The BM1 score (7.7±3.9) was similar to the TF0 score (8.8±4.2) (r=0.86, P<0.0001), but significantly higher than the TF1 score (5.8±3.9) (P<0.0001). A significant correlation was observed between the BM1 score and TF0 score (r=0.86, P<0.0001). Among a total of 1300 segments, the BM1 score was identical to the TF0 score in 1156 (88.9%). These data indicate that the ability of BMIPP imaging at 1 week post AMI to identify areas at risk is similar to that of tetrofosmin perfusion imaging in the acute phase. This may be due to the impairment of fatty acid uptake and metabolism reflecting prior severe ischaemic insult which persists at least 1 week after recovery of perfusion in the acute phase of AMI.


Jacc-cardiovascular Interventions | 2013

Comparison of 5-year outcomes in patients with and without unprotected left main coronary artery disease after treatment with sirolimus-eluting stents: insights from the j-Cypher registry.

Mamoru Toyofuku; Takeshi Kimura; Takeshi Morimoto; Yasuhiko Hayashi; Nobuo Shiode; Hideo Nishikawa; Koichi Nakao; Kinya Shirota; Kazuya Kawai; Yoshikazu Hiasa; Kazushige Kadota; Yoichi Nozaki; Takaaki Isshiki; Takahito Sone; Kazuaki Mitsudo; j-Cypher Registry Investigators

OBJECTIVES This study assessed 5-year outcomes after implantation of sirolimus-eluting stents (SES) for unprotected left main coronary artery (ULMCA) disease in comparison with that for non-left main disease. BACKGROUND More information on long-term outcomes after ULMCA stenting is needed. METHODS The j-Cypher is a multicenter prospective registry of consecutive patients undergoing SES implantation in Japan. RESULTS Among 12,812 patients enrolled in the j-Cypher registry, the unadjusted mortality rate at 5 years was significantly higher in patients with ULMCA stenting than in patients without ULMCA stenting (22.8% vs. 14.1%; p < 0.0001); however, the risk for death with ULMCA stenting was no longer significant after adjusting for confounders (hazard ratio: 1.18, 95% confidence interval: 0.95 to 1.46; p = 0.14). In the lesion-level comparison, the nonbifurcation ULMCA lesions treated exclusively with SES had a significantly lower rate of target lesion revascularization (TLR) than those in non-ULMCA nonbifurcation lesions (2.4% vs. 12.7%; p = 0.04). Among bifurcation lesions, those treated with a provisional 2-stent approach had similar rates of TLR (12.1% vs. 11.4%; p = 0.79) between the ULMCA and non-ULMCA groups. Lesions treated with an elective 2-stent approach had higher TLR rates in the ULMCA group as compared with the non-ULMCA group (33.5% vs. 19.7%; p = 0.002). CONCLUSIONS The safety of ULMCA stenting relative to non-LMCA stenting was maintained through 5 years follow-up. In terms of efficacy, SES implantation in nonbifurcation ULMCA lesions was associated with an extremely low cumulative incidence of TLR, whereas the elective 2-stent approach for ULMCA bifurcation lesions was associated with a markedly higher cumulative incidence of TLR as compared with that for non-ULMCA bifurcation lesions.


Cardiovascular Revascularization Medicine | 2010

A case of successful intervention without a contrast agent for a chronic totally occlusive lesion of the superficial femoral artery

Makoto Utsunomiya; Yoichi Nozaki; Shigeru Nakamura

Peripheral artery disease (PAD) and chronic kidney disease (CKD) commonly occur together and are known to lead to poor long-term survival. Furthermore, it is not yet known whether percutaneous catheter intervention for PAD using contrast agents is beneficial or not for such patients. The risk of CKD patients contracting contrast-induced nephropathy due to the use of contrast agents is frequent. We report a patient with diabetes and CKD in whom a chronic total occlusion lesion of superficial femoral artery was successfully managed with catheter treatment without the use of contrast agents, using various modalities.


Circulation | 2004

Diagnostic Value of 123I-Betamethyl-p-Iodophenyl-Pentadecanoic Acid (BMIPP) Single Photon Emission Computed Tomography (SPECT) in Patients With Chest Pain

Yuko Kawai; Koichi Morita; Yoichi Nozaki; Takanori Ohkusa; Masayuki Sakurai; Nagara Tamaki


Journal of Atherosclerosis and Thrombosis | 2012

Coexistence of Visceral Fat and Multiple Risk Factor Accumulations is Strongly Associated with Coronary Artery Disease in Japanese (The VACATION-J Study)

Aki Hiuge-Shimizu; Ken Kishida; Tohru Funahashi; Masaaki Okutsu; Ryosuke Kametani; Hiroshi Kobayashi; Yoichi Nozaki; Akihiro Nomura; Hiroyoshi Yokoi; Tohru Yoshizumi; Tetsuya Ohira; Tadashi Nakamura; Yuji Matsuzawa; Satoru Sumitsuji; Iichiro Shimomura


Japanese Circulation Journal-english Edition | 2004

Diagnostic value of 123I-betamethyl-p-iodophenyl-pentadecanoic acid (BMIPP) single photon emission computed tomography (SPECT) in patients with chest pain. Comparison with rest-stress 99mTc-tetrofosmin SPECT and coronary angiography.

Yuko Kawai; Koichi Morita; Yoichi Nozaki; Takanori Ohkusa; Masayuki Sakurai; Nagara Tamaki


Cardiovascular Intervention and Therapeutics | 2012

Antiplatelet therapy and long-term clinical outcome after sirolimus-eluting stent implantation: 5-year outcome of the j-Cypher registry

Takeshi Kimura; Takeshi Morimoto; Yoshihisa Nakagawa; Kazushige Kadota; Yoichi Nozaki; Tomohisa Tada; Shunsuke Take; Kinya Shirota; Akira Ito; Hitoshi Nakashima; Hiroshi Fujita; Tomohiro Kawasaki; Tsukasa Inada; Koichi Nakao; Shunichi Miyazaki; Osamu Doi; Takaaki Isshiki; Masakiyo Nobuyoshi; Kazuaki Mitsudo


Archive | 2010

of patients with acute chest pain Significance of reduced uptake of iodinated fatty acid analogue for the evaluation

Nagara Tamaki; Yuko Kawai; Eriko Tsukamoto; Yoichi Nozaki; Koichi Morita; Masayuki Sakurai

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Yuko Kawai

Memorial Hospital of South Bend

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Masayuki Sakurai

Memorial Hospital of South Bend

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