U Ikeda

Shinshu University, Shonai, Nagano, Japan

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Publications (442)1941.96 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose : To examine in claudicant patients with aortoiliac lesions the relationship between the post-exercise ankle-brachial index (ABI) and the peripheral fractional flow reserve (p-FFR), a physiological test that has heretofore been used to assess coronary and renal artery stenosis. Methods : Sixteen male patients (mean age 68.1±7.5 years) with isolated iliac artery lesions detected by ultrasound in 17 limbs were enrolled in this study. Resting ABI was measured and a treadmill test was administered to measure the post-exercise ABI. During angiography, the p-FFR was measured using a pressure guidewire after administration of papaverine to induce hyperemia. Changes in the ABI during exercise and p-FFR at hyperemia were calculated. Results : The mean resting ABI and post-exercise ABI were 0.87±0.12 and 0.65±0.24, respectively. There was no complication during the measurement of p-FFR. The mean p-FFR at hyperemia was 0.71±0.14. A significant linear correlation was observed between post-exercise ABI and p-FFR at hyperemia (r=0.857, p<0.001), which was stronger than the correlation between post-exercise ABI and peak-to-peak pressure gradient at hyperemia (r= -0.626, p=0.013). Conclusions : Measuring p-FFR appears to be a feasible and safe procedure, and there is a significant linear correlation between post-exercise ABI and p-FFR in aortoiliac lesions. The p-FFR was more accurate than a peak-to-peak pressure gradient in assessing the physiological significance of a stenosis. Though larger studies are required, p-FFR might be used to physiologically assess stenosis in PAD patients with isolated aortoiliac lesions.
    Journal of endovascular therapy : an official journal of the International Society of Endovascular Specialists. 10/2014; 21(5):625-632.
  • Journal of Cardiac Failure 10/2014; 20(10):S138–S139. · 3.32 Impact Factor
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    ABSTRACT: Atrial fibrillation (AF) is associated with oxidative stress and elevated brain natriuretic peptide (BNP) levels. However, the exact cardiac origin of oxidative stress and its association with BNP levels in AF patients remain unclear. Therefore, we investigated the chamber-specific plasma oxidative stress levels in patients with paroxysmal AF (PAF) and persistent AF (PSAF). Diacron-reactive oxygen metabolite (dROM) levels were measured in patients with PAF (n = 50) and PSAF (n = 35) at different cardiac sites before ablation and in peripheral vein 3 months after ablation. For all sites, dROM levels were higher in PSAF patients than in PAF patients; the levels were the highest in the coronary sinus at 429.0 (interquartile range: 392.0-449.0) vs. 374.0 (357.0-397.8) Carratelli units (P < 0.05). dROM levels in the coronary sinus were related to the BNP levels (r = 0.436, P < 0.001). Furthermore, the reduction in the peripheral dROM levels was related to that in the peripheral BNP levels in patients with symptomatic improvement (r = 0.473, P < 0.001). Cardiac oxidative stress may either be a cause or consequence of prolonged AF, and cardiac oxidative stress levels correlated with BNP levels, though a possible source of oxidative stress in AF patients may be systemic circulation.
    Heart and vessels. 09/2014;
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    ABSTRACT: Recent guidelines for treating ventricular fibrillation (VF) and ventricular tachycardia (VT) stress class III antiarrhythmic drugs, but some malignant arrhythmias refractory to these agents still occur in clinical practice. The possibility of a new treatment strategy involving lidocaine and amiodarone combination therapy was evaluated.
    International journal of cardiology. 08/2014;
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    ABSTRACT: A 60-year-old woman was hospitalized with cardiac tamponade due to effusive pericarditis presenting with significant thickening of the pericardium. Serum immunoglobulin G4 (IgG4) level was elevated to 1,800 mg/dL, and an open biopsy specimen from the pericardium revealed massive infiltration of lymphocytes and IgG4-positive plasma cells. She had experienced adenopathies in the lacrimal and parotid glands 6 months earlier, and was diagnosed as having IgG4-related Mikulicz's disease by similar cell infiltration in the salivary gland biopsy. The significant involvement of the pericardium as a manifestation of IgG4-related disease is described, as well as the successful treatment with oral corticosteroids.
    The Annals of thoracic surgery. 08/2014; 98(2):e47-9.
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    ABSTRACT: Purpose : To examine the prognosis of patients with intermittent claudication who received treatment with endovascular techniques. Methods : A retrospective multicenter study was performed involving 2930 consecutive patients (2307 men; mean age 71.5±8.9 years) with intermittent claudication who underwent an endovascular procedure for a de novo iliofemoral artery lesion. The primary outcome measure was overall survival. The secondary outcomes were freedom from major adverse cardiovascular events (MACE: all-cause death, myocardial infarction, and stroke) and from major adverse cardiovascular and limb events (MACE with repeat revascularization or above-knee amputation of the target limb). Cox multivariate regression analysis of selected baseline characteristics, procedure-related complications, and medication use was performed to determine predictors for all-cause mortality. Positive predictors from this analysis were used to stratify patients into low- (1410, 48.1%), moderate- (1406, 48.0%), and high-risk (114, 3.9%) categories. Results : The overall survival rates were 97.2%, 90.8%, and 83.4% at 1, 3, and 5 years, respectively. The cause of death was cardiovascular in 42.8% of cases. Freedom from MACE was 96.7%, 88.6%, and 77.3% at 1, 3, and 5 years, respectively. Cox multivariate regression analysis identified age, dialysis, left ventricular dysfunction, insulin-dependent diabetes, hematoma prolonging hospitalization, coronary artery disease, and superficial femoral plus iliac lesions as positive predictors of all-cause mortality. In the risk stratification analysis, the overall 5-year survival rate was significantly lower in high-risk patients compared to the other groups (90.1% vs. 78.6% vs. 53.5%, p<0.0001). Conclusion : The prognosis in patients with intermittent claudication after endovascular therapy was relatively good but extremely poor for the high-risk patient subgroup.
    Journal of endovascular therapy : an official journal of the International Society of Endovascular Specialists. 06/2014; 21(3):381-388.
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    ABSTRACT: Background: Atherosclerosis is believed to be caused by oxidative stress. Endovascular therapy (EVT) is effective for claudication of patients with peripheral artery disease (PAD). However, its effect on oxidative stress in PAD patients is unknown. Here, the impact of EVT on oxidative stress in PAD patients is investigated. Methods and Results: Twenty-five PAD patients (Rutherford stage II or III) who underwent EVT were enrolled. The levels of diacron-reactive oxygen metabolite (d-ROM; an oxidative stress marker), ankle-brachial index (ABI), and maximum walking distance at baseline and at 3 months after EVT were measured. As compared with baseline values, the maximum walking distance and ABI improved significantly after EVT (109.9±104.2 vs. 313.7±271.8m, P<0.0001; 0.61±0.15 vs. 0.91±0.13m, P<0.0001, respectively). The improved exercise capacity and arterial flow induced a significant decrease in d-ROM levels (from 472.8±64.8 to 390.2±46.7U.CARR; P<0.0001). The decrease in d-ROM levels after EVT was more prominent in PAD patients with a high baseline d-ROM level. The increased ABI (r=0.524, P=0.0007) and maximum walking distance (r=-0.416, P=0.039) after EVT were significantly correlated with the decreased d-ROM levels. Conclusions: The improved exercise capacity and peripheral blood flow induced by EVT decreases oxidative stress in PAD patients.
    Circulation Journal 03/2014; · 3.58 Impact Factor
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    ABSTRACT: Background: The clinical outcomes of elderly patients (≥80 years old) undergoing percutaneous coronary intervention (PCI) has not been well established, despite recent advances in both devices and techniques. Methods and Results: We recruited patients from the SHINANO Registry, a prospective, observational, multicenter, cohort study. From August 2012 to July 2013, a total of 1,923 consecutive patients with 2,250 elective/urgent PCIs (2,105 admissions) (mean age, 71±11 years; ≥80 years, 23%; men, 77%) were enrolled. The primary endpoint was procedural success. The secondary endpoints were in-hospital death and in-hospital major adverse cardiovascular events (MACE). The procedural success rate was significantly lower (83.7% vs. 89.1%, P=0.0001), and the rates of in-hospital mortality and MACE were significantly higher in elderly than in non-elderly patients (3.6% vs. 1.5%, P=0.005; 4.4% vs. 2.3%, P=0.016, respectively). For elective PCI, the rates of procedural success and in-hospital MACE were similar between groups (90.3% vs. 91.3%, P=0.65, 2.3% vs. 1.2%, P=0.2, respectively). On multivariate analysis, being elderly was not an independent predictor of procedural failure (OR, 1.15; CI, 0.81-1.61; P=0.43). Conclusions: In elderly patients, PCI is safe and feasible. The presence of comorbidities is a more important factor than age alone.
    Circulation Journal 03/2014; · 3.58 Impact Factor
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    ABSTRACT: We sought to determine whether serial measurements of oxidative stress levels could serve as a predictive marker for cardiovascular (CV) events in patients with ST-segment elevation myocardial infarction (STEMI). Biological antioxidant potential (BAP) levels were measured at admission and at 6, 12, and 24 months in 69 patients with STEMI. The CV events abruptly increased 6 to 10 months after successful percutaneous coronary intervention in patients with STEMI, and the 6-month BAP levels were significantly lower in patients with CV events (2456 μmol/L [interquartile range: 2237-2615 μmol/L]) than in those without (2849 μmol/L [2575-2987 μmol/L], P < .001). A decreased 6-month BAP level was an independent and significant predictor of long-term CV events (hazard ratio = 2.45; 95% confidence intervals 1.10-5.78; P = .04). Our findings suggest that serial changes in antioxidant capacity, assessed by BAP levels, may serve as a predictive marker for CV events after STEMI.
    Angiology 03/2014; · 2.37 Impact Factor
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    ABSTRACT: Background The impact of long-acting calcium channel blocker (CCB) administration on serial changes in left ventricular (LV) function and morphology in hypertensive patients with LV hypertrophy remains unclear. This study attempted to clarify this impact by comparing the effects of administration of azelnidipine with that of amlodipine using conventional and speckle tracking echocardiography.Methods An equal number (16) of 32 hypertensive patients was prospectively assigned to a group administered 5 mg of amlodipine/day or a group administered 16 mg of azelnidipine/day. LV function and morphology was examined by conventional and speckle tracking echocardiography at baseline and at 1, 3, 6, and 12 months after treatment initiation.ResultsBoth groups were found to have experienced a significant decrease in systolic blood pressure by 1 month after treatment initiation; a significant reduction in septal thickness and LV mass index at 6 and 12 months. Transmitral flow E/A ratio and early diastolic mitral annular velocity at lateral wall significantly improved at 12 months. On the other hand, a significant improvement of global longitudinal strain was observed earlier than the above indexes at 3, 6, and 12 months. Ar-A duration difference was significantly decreased at 3 months. The global circumferential strain improved significantly at 3 months, but there were no significant changes in mid-/apical circumferential and radial strains throughout the study period.Conclusion Azelnidipine has beneficial effects on LV mass regression, transmitral flow, tissue Doppler, and LV longitudinal strain that are comparable to those of amlodipine on the same parameters.
    Echocardiography 03/2014; · 1.26 Impact Factor
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    ABSTRACT: Although limb salvage rate has improved in critical limb ischemia (CLI), an improvement in CLI prognosis has been scarcely reported. Multidisciplinary therapy (MT) including revascularization, wound bed preparation, treatment of comorbidity, and education of patients with CLI may improve prognosis. The aim of this study was to investigate the effectiveness of MT in prognostic improvement. We retrospectively analyzed 72 patients with CLI and assessed whether MT improved prognosis. The incidence of amputation-free survival (freedom from major amputation [MA] and death) was significantly different between the MT and conventional groups at 2 years (0% vs 33%; P = .024). After multivariate analysis, transfusion (hazard ratio [HR] 5.778; 95% confidence interval [CI], 2.372-14.073; P < .001), multivessel coronary disease (HR 3.353; 95% CI, 1.309-8.590; P = .012), and C-reactive protein >5 mg/dL (HR 3.958; 95% CI, 1.359-11.531; P = .012) were independent predictors for MA or death. We concluded that MT was effective in improved mortality and limb salvage rate.
    Angiology 02/2014; · 2.37 Impact Factor
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    ABSTRACT: We herein report a case of infective endocarditis associated with mitral valve prolapse (MVP) in a 34-year-old man with Klinefelter syndrome. The patient was admitted with a fever and headache that had persisted for three weeks. Repeated blood cultures showed growth of Streptococcus oralis. Echocardiography demonstrated severe mitral regurgitation with a large vegetation attached to the prolapsed anterior leaflet. Surgical plasty of the mitral valve was performed because the vegetation measured over 10 mm in diameter and there was a risk of recurrence of embolic complications. This case demonstrates the link between MVP and Klinefelter syndrome and highlights the importance of performing cardiovascular screening and preventing endocarditis.
    Internal Medicine 01/2014; 53(9):969-972. · 0.97 Impact Factor
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    ABSTRACT: A 15-year-old asymptomatic male patient presented with an electrocardiographic abnormality and left ventricular (LV) dysfunction (left ventricle ejection fraction of 40%) in a physical examination performed 2 years previously. LV dysfunction did not improve despite optimal medical therapy for dilated cardiomyopathy. Twelve-lead electrocardiography revealed a normal PR interval (138 ms) with a small delta-like wave in V2, but not a typical diagnostic wave that could be diagnosed as Wolff–Parkinson–White (WPW) syndrome by an electrocardiogram auto-analysis. Transthoracic echocardiography showed a remarkable asynchronous septal motion. An electrophysiological study was performed to exclude WPW syndrome. An accessory pathway (AP) was revealed on the lateral wall of the right ventricle, and radiofrequency catheter ablation was successfully performed to disconnect the AP. Thereafter, the dyssynchrony disappeared, and LV function improved. The intrinsic atrioventricular nodal conduction was very slow (A-H, 237 ms). The results of electrocardiogram auto-analysis could not be used to confirm the diagnosis of WPW syndrome because of the atypical delta wave. Conduction via the right lateral AP caused electrical dyssynchrony in the LV. This case suggests that atypical delta waves should be evaluated without depending on electrocardiographic auto-analyses in patients with LV dysfunction accompanied by dyssynchrony.
    Journal of Arrhythmia 01/2014;
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    ABSTRACT: Importance of fatty acid components and imbalances has emerged in coronary heart disease. In this study, we analyzed fatty acids and ankle-brachial index (ABI) in a Japanese cohort.
    PLoS ONE 01/2014; 9(9):e107003. · 3.53 Impact Factor
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    ABSTRACT: We assessed the relationship between J waves and the ventricular morphology and function using cardiac magnetic resonance imaging (MRI). The 12-lead electrocardiograms (ECGs) of 105 consecutive patients who underwent cardiac MRI were reviewed, and those with signs of arrhythmogenic right ventricular cardiomyopathy, complete left bundle branch block, complete right bundle branch block, or chronic atrial fibrillation, where the J wave is difficult to distinguish, were excluded. The ECGs of the remaining 68 patients were analyzed for the presence of J waves. Ventricular morphologic abnormalities were identified on MRI, based on the largest short-axis diameter in the right and left ventricles (d-RVmax/d-LVmax), the area (a-RVmax/a-LVmax), and the ratio RV/LVmax. The percentage contraction of the RV (PC-RV) was used as a measure of ventricular function. Thirty-two patients (47.0 %) had J waves defined as QRS-ST junction elevation >0.1 mV from baseline in the inferior/lateral leads (J group; 56 ± 15 years; 19 males). Thirty-six patients (53.0 %) did not present J waves (NJ group; 58 ± 15 years; 27 males). The d-RVmax and a-RVmax in the J group were larger than those in the NJ group (41 ± 5.2 vs 36 ± 6.6 mm, P = 0.002 and 14 ± 2.9 vs 12 ± 3.4 cm(2), P = 0.022, respectively). The RV/LVmax ratio in the J group was larger than that in the NJ group (0.83 ± 0.15 vs 0.68 ± 0.15, P < 0.001). The PC-RV in the J group was smaller than that in the NJ group (0.28 ± 0.14 vs 0.36 ± 0.15, P = 0.013). J-wave amplitude was correlated positively with d-RVmax (P = 0.010) and negatively with PC-RV (P = 0.005). These results suggested that J waves are associated with right ventricular morphologic and functional abnormalities.
    Heart and Vessels 11/2013; · 2.13 Impact Factor
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    ABSTRACT: To identify predictors of the presence of coronary artery disease (CAD) in patients with planned surgery for aortic aneurysms, we reviewed clinical profiles and angiography records of 191 patients with aortic aneurysms (34 thoracic, 137 abdominal, and 20 thoracoabdominal; 162 men; mean age, 75.2 ± 7.7 years). The incidence of CAD was 38.7% among all the patients. Patients with CAD had significantly low levels of high-density lipoprotein cholesterol (HDL-C) as compared with patients without CAD (45 ± 9 vs 51 ± 13 mg/dL; P = .009). Multivariate analysis showed that only low HDL-C levels were associated with the presence of CAD (adjusted odds ratio, 0.946; 95% confidence interval, 0.911-0.983; P = .004). The optimal cutoff level of HDL-C to predict CAD was 47.50 mg/dL. The CAD is common in patients with aortic aneurysms, and low levels of HDL-C are independently associated with the presence of CAD.
    Angiology 09/2013; · 2.37 Impact Factor
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    ABSTRACT: Renal artery stenting is expected to improve or stabilize renal function. However, the efficacy of renal artery stenting in severely reduced renal function is unclear. We evaluated 23 patients with class IV or V renal dysfunction who were treated for renal artery stenosis between 2004 and 2009. Improvement in renal function was found in 7 (30%) patients, all of whom were treated with distal protection device. Deterioration of renal function was found in 4 (17%) cases. In these 4 cases, distal protection device could not be used for anatomical reasons. The use of distal protection device was associated with significantly less renal deterioration after the procedure (P < .05, odds ratio 0.21 [confidence interval 0.09-0.50]). Renal artery stenting can stabilize or improve renal function in patients with severe renal dysfunction. Distal protection devices may be beneficial in patients who require renal artery stenting due to severely reduced renal function.
    Angiology 09/2013; · 2.37 Impact Factor
  • International journal of cardiology 08/2013; · 6.18 Impact Factor
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    ABSTRACT: During the treatment of coronary artery disease, the no-reflow phenomenon can lead to severe impairment of viable cardiac muscle and all necessary measures should be taken to prevent it. Excimer laser coronary atherectomy (ELCA) may be indicated for lesions with a large thrombus burden due to potential to ablate thrombi and necrotic plaques. However, there are few reports on the use of ELCA for the prevention of distal embolism. Here, we report a case involving severe left ventricular dysfunction with a previous extensive anterior infarction, where ELCA was used in the right coronary artery to prevent the no-reflow phenomenon.
    Cardiovascular intervention and therapeutics. 05/2013;
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    ABSTRACT: Tumors of the heart and the great vessels are very rare disease, and there are many disorders such as tumors originated from the heart and great vessels, metastatic tumors, and tumor-like lesions which do not fit into the usual concept of tumor or neoplasm; thus, it is very difficult to classify these tumors. We proposed a new classification of cardiovascular tumors for clinical use based on the accumulated biological analyses and clinical data of the reported literatures and our own study as benign tumors, malignant tumors, ectopic hyperplasia/ectopic tumors/others, and tumors of great vessels, with reference to the series of Atlas of tumor pathology of the Armed Forces Institute of Pathology and the recent World Health Organization classification of cardiac tumors issued in 2004. More than 50 disorders have been reported as tumors originated from the cardiovascular system, and various metastatic tumors from nearby organs, distant lesions, and intravascular extension tumors to the heart were reported. Based on the new classification, we reviewed epidemiology and incidence of cardiovascular tumors. Metastatic tumors are more frequent than tumors originated from the heart and great vessels, and cardiac myxoma is the most frequent tumors in all cardiac tumors.
    General Thoracic and Cardiovascular Surgery 03/2013;

Publication Stats

7k Citations
1,941.96 Total Impact Points


  • 2004–2014
    • Shinshu University
      • Division of Cardiovascular Medicine
      Shonai, Nagano, Japan
    • Tokyo Institute of Technology
      • Department of Biomolecular Engineering
      Edo, Tōkyō, Japan
  • 2012
    • Aizawa Hospital
      Honjō, Saitama, Japan
  • 1986–2011
    • Jichi Medical University
      • • Center for Molecular Medicine
      • • Department of Genetic Therapeutics
      • • Division of Cardiology
      • • Division of Molecular Physiology and Biophysics
      • • Department of Medicine
      Totigi, Tochigi, Japan
  • 2003
    • North Internal Medicine
      Bartlett, Tennessee, United States
  • 1997–2001
    • Utsunomiya University
      Totigi, Tochigi, Japan
  • 1991
    • Emory University
      • School of Medicine
      Atlanta, GA, United States
  • 1990
    • Brigham and Women's Hospital
      • Department of Medicine
      Boston, MA, United States