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Featured researches published by Takuya Miyahara.


Surgery Today | 1999

Sigmoid Colon Cancer Associated with Primary Hyperparathyroidism: Report of a Case

Yutaka J. Kawamura; Shinsuke Kazama; Takuya Miyahara; Tadahiko Masaki; Tetsuichiro Muto

We present herein a case of sigmoid colon cancer associated with primary hyperparathyroidism (PHP). PHP is known to be associated with malignancy, and decreased intracolonic calcium (Ca) resulting from increased vitamin D (VD) levels may play a role in colorectal carcinogenesis. PHP was diagnosed in this patient by preoperative screening blood chemistry examination. The blood level of intact parathyroid hormone (PTH) was elevated and a parathyroid gland scintigram demonstrated abnormal uptake near the right lower lobe of the thyroid. There was no evidence of bone metastasis, and a sigmoid colectomy was performed with curative intent. The patient had an uneventful postoperative course without a critical elevation of the serum Ca level. This case report suggests that a relationship exists between PHP and colon cancer, and the possible mechanisms of this association are presented in our discussion.


Journal of Vascular Surgery | 2016

Favorable outcomes of very elderly patients with critical limb ischemia who undergo distal bypass surgery

Takuro Shirasu; Katsuyuki Hoshina; Ayako Nishiyama; Daisuke Akagi; Takuya Miyahara; Kota Yamamoto; Kunihiro Shigematsu; Toshiaki Watanabe

OBJECTIVE To determine the midterm outcomes of distal bypass surgery for very elderly patients, and to determine the ideal candidates for this procedure. METHODS Of 268 consecutive patients (328 limbs) with critical limb ischemia who were treated between 2006 and 2013, 106 (126 limbs) underwent distal bypass and were retrospectively reviewed. Nineteen patients (22 limbs) were aged ≥80 years (very elderly group) and 87 patients (104 limbs) were aged <80 years (control group). RESULTS The baseline characteristics differed between the 2 groups in terms of regular hemodialysis rate (very elderly group, 4 [21%] vs control group, 60 [69%]; P = .0002) and the Charlson comorbidity index (very elderly group, 3.2 ± 1.7 vs control group, 5.0 ± 2.0; P = .0005). According to the Rutherford category of limb ischemia (4/5/6), the very elderly and control groups were classified as 5/17/0 and 11/87/6, respectively (P = .18). Before the surgery, 17 patients (77%) and 67 patients (64%) were ambulatory in the very elderly and control groups, respectively. At follow-up at 29 ± 22 months, the rates of primary (P = .33) and secondary patency (P = .14), limb salvage (P = .50), survival (P = .26), amputation-free survival (P = .42), major adverse limb event and also perioperative death (P = .11), and major adverse cardiovascular events (P = .36) did not significantly differ between the groups. In multivariate analysis, a history of coronary artery disease (hazard ratio [HR], 2.7; 95% confidence interval [CI], 1.3-5.9; P = .005), preoperative nonambulatory status (HR, 4.2; 95% CI, 2.1-8.1; P < .0001), and serum albumin levels <3 g/dL (HR, 2.7; 95% CI, 1.3-5.4; P = .01) were significantly related to poor amputation-free survival. Thirteen patients (59%) remained ambulatory at the latest follow-up. In 91 patients (110 limbs) with tissue loss, the Society for Vascular Surgery lower extremity threatened limb classification system: risk stratification based on Wound, Ischemia, and foot Infection classification stages 3 and 4 negatively affected complete wound healing, according to multivariate analysis (HR, 0.34; 95% CI, 0.20-0.61; P = .0005). CONCLUSIONS A very elderly age should not preclude a patient from undergoing distal bypass surgery. A history of coronary artery disease, a nonambulatory status, and hypoalbuminemia, along with the Wound, Ischemia, and foot Infection classification for patients with tissue loss, should be carefully considered to obtain the most benefit from distal bypass surgery.


Journal of Atherosclerosis and Thrombosis | 2015

Viscoelastic Deterioration of the Carotid Artery Vascular Wall is a Possible Predictor of Coronary Artery Disease

Ryosuke Taniguchi; Akihiro Hosaka; Takuya Miyahara; Katsuyuki Hoshina; Hiroyuki Okamoto; Kunihiro Shigematsu; Tetsuro Miyata; Ryuji Sugiura; A. Toshimitsu Yokobori; and Toshiaki Watanabe

AIM The viscoelastic properties of the artery are known to be altered in patients with vascular diseases. However, few studies have evaluated the viscoelasticity of the vascular wall in humans. We sought to investigate the degree of viscoelastic deterioration of the carotid artery and assess its clinical implications. METHODS Between January 2011 and June 2013, patients in whom the toe-brachial index was measured at the vascular laboratory were included in this single-institute retrospective observational study. I(*), a parameter of viscoelastic deterioration, was computed using a non-invasive ultrasonic Doppler effect sensor on the carotid artery. I(*) is a non-dimensional value, and I(*)>0 is considered abnormal. Other patient characteristics were identified and tested for correlations with I(*). RESULTS The study included 383 patients. The mean I(*) value was 0.13 ± 0.22 with a normal distribution. Factors that increased the I(*) value were a female sex (0.18 ± 0.23 vs. 0.10 ± 0.21, P<0.001), age ≥ 60 (0.14 ± 0.22 vs. 0.06 ± 0.23, P<0.05) and systolic blood pressure of >140 (0.15 ± 0.22 vs. 0.10 ± 0.22, P<0.05). I(*) abnormality was a significant risk factor for coronary artery disease (OR 2.20, 95% CI 1.00-4.80, P<0.05) in a univariate analysis. In the multivariate analysis, I(*) abnormality was also found to be an independent risk factor for coronary artery disease (OR 4.56, 95% CI 1.21-30.1, P<0.05). CONCLUSIONS I(*) may reflect the degree of atherosclerotic changes in the arterial wall and could possibly be used to predict coronary artery disease.


Annals of Vascular Diseases | 2015

Long-Term Results of Treatment for Critical Limb Ischemia.

Takuya Miyahara; Masamitsu Suhara; Yoko Nemoto; Takuro Shirasu; Makoto Haga; Yasuaki Mochizuki; Mitsuru Matsukura; Takafumi Akai; Ryosuke Taniguchi; Masaru Nemoto; Satoshi Yamamoto; Ayako Nishiyama; Akihiro Hosaka; Katsuyuki Hoshina; Hiroyuki Okamoto; Kunihiro Shigematsu; Tetsuro Miyata; Toshiaki Watanabe

From 2001 to 2012, arterial reconstruction was performed in 306 out of 497 limbs (62%) with critical limb ischemia. The reasons for non-vascularization include high operative risk (36%), extended necrosis or infection (20%), and technical issues (15%). Cumulative patency and limb salvage in collagen disease were significantly worse compared to arteriosclerosis obliterans. Cumulative limb salvage, amputation free survival (AFS), and major adverse limb event and perioperative death (MALE + POD) in patients with end-stage renal disease (ESRD) were significantly worse compared to patients without ESRD, but not significant with regards to graft patency. Our finding suggests that aggressive arterial reconstruction provides satisfactory long-term results in critical limb ischemia so long as case selection for revascularization is properly made. (This article is a translation of J Jpn Coll Angiol 2014; 54: 5-11.).


Surgery Today | 2010

Do inferior vena cava filters reduce the risk of acute pulmonary embolism in preoperative patients with venous thromboembolism

Juno Deguchi; Mikiko Nagayoshi; Takuya Miyahara; Seiji Nishikage; Hideo Kimura; Kunihiro Shigematsu; Tetsuro Miyata

PurposeAlthough prophylactic anticoagulants reduce the risk of acute pulmonary embolism (PE), inferior vena cava filters (IVCF) remain elusive in prophylactic use. This study investigated whether IVCF in addition to anticoagulants augment the prophylactic effect on acute PE in the highest-risk patients.MethodsThis study included patients with existing venous thromboembolism (VTE) or a history of previous PE, who underwent subsequent surgery for the underlying disease. The hospital records of the patients were reviewed.ResultsForty-nine consecutive patients treated from October 2001 to June 2007 were assessed, including 13 men and 36 women with a mean age of 58.1 years. The underlying diseases that required surgery included malignancy in 23, orthopedic disorder in 14, and others in 12. All patients received anticoagulants, with perioperative IVCF in 31 patients or without in 18. Neither group had any fatal complications. The no-filter group had no cases of recurrent PE, whereas the filter group had one case of recurrent PE just after placement of the filter. Moreover, 5 cases in the filter group had filter-related complications.ConclusionThis study suggested that the addition of IVCF to anticoagulants does not provide a substantial risk reduction for perioperative patients with VTE prior to surgery.


Annals of Vascular Diseases | 2014

Penetration of an inferior vena cava filter into the aorta.

Makoto Haga; Akihiro Hosaka; Takuya Miyahara; Katsuyuki Hoshina; Kunihiro Shigematsu; Toshiaki Watanabe

Transvenous placement of inferior vena cava (IVC) filters is commonly performed in selected patients with deep venous thrombosis and pulmonary embolism. However, filter placement is sometimes associated with serious complications. A common complication is asymptomatic perforation of the IVC and penetration of adjacent organs by the filter. Here, we report a case of an 83-year-old man whose prophylactic IVC filter penetrated the aorta. The patient was closely followed without surgical intervention for more than a year, and no additional complications were observed.


Vascular Medicine | 2018

Increase in skin perfusion pressure predicts amputation-free survival after lower extremity bypass surgery for critical limb ischemia:

Kota Yamamoto; Takuya Kawahara; Atsushi Akai; Toshihiko Isaji; Daisuke Akagi; Takuya Miyahara; Katsuyuki Hoshina

The objective of this study was to determine how postoperative skin perfusion pressure (SPP) as a measure of blood flow after revascularization affects limb prognosis in patients with critical limb ischemia (CLI). We retrospectively reviewed 223 consecutive bypass surgery cases performed in 192 patients with CLI during a 10-year period. SPP was measured 1–2 weeks before and after the procedure. An SPP of 40 mmHg was set as the cut-off value for revascularization. Patients were grouped according to their postoperative SPPs, and amputation-free survival (AFS) was analyzed. An SPP of ≥ 40 mmHg was recovered in 75% of the patients, but no significant difference was found between this group and the group that did not reach 40 mmHg. On the other hand, the values increased by ≥ 20 mmHg from the preoperative values in 70% of the patients. This group had a significantly better AFS than the group that did not increase by 20 mmHg. Logistic regression analysis revealed that (1) a preoperative SPP of < 20 mmHg and (2) a high serum albumin level (> 3.0 g/dL) were significant factors in increasing SPP by 20 mmHg. These results showed that an increase in SPP of ≥ 20 mmHg after bypass surgery was associated with better limb prognosis.


Annals of Vascular Diseases | 2018

Efficacy of Preoperative Antibiotic Therapy for the Treatment of Vascular Graft Infection

Takuya Miyahara; Katsuyuki Hoshina; Masahiko Ozaki; Masanori Ogiwara

Objective: We aimed to assess the efficacy of preoperative antibiotic therapy for the treatment of prosthetic graft infection. Materials and Methods: We retrospectively analyzed the treatment strategies used for managing patients with prosthetic vascular graft infections between 2000 and 2016. The patients were divided into two groups: early antibiotic (EA) group, those who were administered with antibiotics ≥2 weeks preoperatively and late antibiotic (LA) group, those who were administered with antibiotics <2 weeks preoperatively. We evaluated the outcomes including surgical procedures, length of hospital stay, and surgical revision. Results: All the surgical procedures performed in the EA group were elective surgeries. Three of the 11 surgeries performed in the LA group were emergency surgeries (P=0.16). No significant differences were observed in the operative procedure (P=0.64), operation time (P=0.37), and blood loss (P=0.63) of the two groups. Although the length of postoperative hospital stay did not significantly differ (P=0.61), the total length of hospital stay was longer in the EA group (P=0.02). Surgical revisions were performed for five patients in the LA group and for none in the EA group (P=0.04). Conclusion: Preoperative antibiotic therapy provided excellent outcomes in terms of avoiding surgical revisions in the treatment of vascular graft infection.


Asian Cardiovascular and Thoracic Annals | 2017

Stenotic lesion level did not affect outcomes of carotid endarterectomy

Masamitsu Suhara; Katsuyuki Hoshina; Atsushi Akai; Toshihiko Isaji; Daisuke Akagi; Kota Yamamoto; Takuya Miyahara; Toshiaki Watanabe

Background Carotid endarterectomy is the established treatment for carotid artery stenosis, and remains the primary surgical option due to its superior outcomes compared to carotid arterial stenting. However, Japanese patients are known to have unfavorable anatomical conditions for carotid endarterectomy, with a relatively higher level of the carotid artery bifurcation than in the Western population. We investigated the outcomes of carotid endarterectomy in our institute and evaluated the procedural quality by comparing patients based on higher or lower lesion levels. Methods The clinical data of 65 patients who underwent carotid endarterectomy were collected retrospectively. The outcomes reviewed included stroke-free survival and stroke-free rate. The patients were divided into a higher group (n = 25) and a lower group (n = 40), based on lesion location in respect of the 2nd cervical vertebral level. Results There was no perioperative death and only one case of stroke in the higher group within 30 days after carotid endarterectomy. At 5 years after carotid endarterectomy, the stroke-free survival rates were 83.4% in the higher group and 87.8% in the lower group, while the stroke-free rates were 96.0% and 94.0%, respectively; there were no significant differences between groups. Conclusions Stenotic lesion level did not affect the outcome or procedural quality of carotid endarterectomy.


Journal of Vascular Surgery | 2016

Preservation of the accessory renal arteries after endovascular repair of common iliac artery aneurysm using kissing stent grafts

Akihiro Hosaka; Tetsuro Miyata; Ayako Nishiyama; Takuya Miyahara; Katsuyuki Hoshina; Kunihiro Shigematsu

Exclusion of the accessory renal arteries (ARAs) is required during endovascular aneurysm repair if they arise from the sealing zone or aneurysm sac. Here, we report a case of successful endovascular treatment for a common iliac artery aneurysm located close to the aortic bifurcation and associated with nephrotic syndrome in a 51-year-old man. The bilateral ARAs were successfully preserved using kissing stent grafts. During surgery, the proximal ends of endografts inserted from the bilateral femoral arteries were adjusted so that they met at the same level in the aorta, and simultaneous balloon dilatation was performed. This method can be a useful treatment option for common iliac aneurysms in cases with large ARAs.

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Kunihiro Shigematsu

International University of Health and Welfare

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Tetsuro Miyata

Society for Vascular Surgery

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