Noriaki Iwahashi

Yokohama City University, Yokohama, Kanagawa, Japan

Are you Noriaki Iwahashi?

Claim your profile

Publications (47)161.56 Total impact

  • Noriaki Iwahashi, Toshiaki Ebina, Kazuo Kimura
    Journal of Cardiac Failure 10/2014; 20(10):S136. · 3.32 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We sought to compare the morphological features of non-culprit plaques with >50% diameter stenosis in patients with acute coronary syndromes (ACS) with those of culprit plaques in patients with ACS and stable angina pectoris (SAP) using optical coherence tomography (OCT) and integrated backscatter intravascular ultrasound (IB-IVUS).
    European Heart Journal – Cardiovascular Imaging 09/2014; · 3.67 Impact Factor
  • International journal of cardiology. 08/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Venous thromboembolism (VTE) is a common and sometimes lethal postoperative complication of arthroplasty. Endothelial dysfunction is important in the pathogenesis of thrombus formation. Reactive hyperemia-peripheral arterial tonometry (RH-PAT) can noninvasively evaluate endothelial function. This study investigated the predictive value of RH-PAT for deep vein thrombosis (DVT) after lower limb arthroplasty. Methods and Results: A prospective observational study of 126 osteoarthritic patients who underwent total knee arthroplasty (TKA) or hip arthroplasty (THA) was conducted. The RH-PAT index (RHI) was measured on the day before surgery, and presence of DVT was checked by ultrasonography or phlebography before and after surgery. Following arthroplasty, DVT was diagnosed in 51 patients (40.5%). RHI in the DVT group (0.58±0.25) was significantly lower than in the non-DVT group (0.71±0.25, P=0.004). RHI was a significant and independent predictor of postoperative DVT in multivariate logistic regression analyses and improved a net reclassification index (23.8%, P=0.022). Subgroup analyses according to operation site with adjustment for Qthrombosis score demonstrated that RHI significantly predicted postoperative DVT in the THA group (odds ratio per 0.1, 0.77; 95% confidence interval 0.60-0.98; P=0.03), but did not reach statistical significance in the TKA group. Conclusions: Low RHI was significantly associated with DVT after lower limb arthroplasty. Endothelial dysfunction, as assessed by RH-PAT, is potentially useful for identifying patients at high risk for VTE especially after THA.
    Circulation Journal 04/2014; · 3.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Acute pulmonary edema (APE) often occurs without remarkable fluid retention, and the benefits of diuretics are unclear in such patients. Although aggressive diuresis induces an increase in intravascular substances including hemoglobin (Hb), acute changes in Hb level remain to be investigated. Methods and Results: We analyzed 237 consecutive acute heart failure patients (74±12 years; 60.8% men) without shock, hemodialysis, bleeding, or urgent coronary angiography. APE was defined as acute onset of dyspnea within the preceding 6h and radiographic alveolar edema requiring immediate airway intervention. At admission, Hb level was higher in APE (n=29) than non-APE patients (n=208; 13.4±2.2 vs 12.2±2.1g/dl, P<0.01). Although diuretic therapy was performed in 232 patients (97.9%), hemoconcentration (ie, any increase in Hb) was observed in only 64 patients (27.0%) at 24h after admission. Conversely, Hb level decreased in both groups and the difference was larger in APE patients (-1.8±1.1 in APE and -0.5±1.0g/dl in non-APE patients, P<0.001). APE was significantly related to a greater decrease in Hb after adjusting for baseline Hb (β=-1.08g/dl, SE=0.20, P<0.001, ANCOVA). Conclusions: APE patients had higher Hb level at admission and a more remarkable decline in 24h than did those without APE. Acute change in Hb might be caused by factors other than diuresis-induced hemoconcentration. The present findings may be useful in the selection of diuretic strategies.
    Circulation Journal 01/2014; · 3.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Patients with acute pulmonary embolism (APE) often have negative T waves (Neg T) in precordial leads at presentation, but this is also found in acute coronary syndrome (ACS) caused by left anterior descending coronary artery (LAD) disease. Methods and Results: Differences in Neg T on admission electrocardiograms were studied between 107 patients with APE and 248 patients with ACS caused by LAD disease. All patients had Neg T in leads V1-4 and were admitted within 7 days from symptom onset. The number of leads with Neg T (4.8±1.8 vs. 5.5±1.7, P<0.001) and maximum magnitude of Neg T (3.4±2.0 vs. 4.7±3.3mm, P<0.001) were lower in APE. The frequency of occurrence of Neg T in each of the 12 leads, and the precordial lead with the greatest Neg T (peak Neg T) differed between APE and ACS (all P<0.05, respectively). APE was strongly associated with the presence of Neg T in both leads III and V1 and peak Neg T in leads V1-2. The combination of these 2 findings identified APE with 98% sensitivity, 92% specificity, and 94% predictive accuracy, which represented the highest diagnostic accuracy. Conclusions: Among patients with APE and ACS who have precordial Neg T, the presence of Neg T in leads III and V1 and/or peak Neg T in leads V1-2 simply but accurately differentiates APE from ACS.
    Circulation Journal 12/2013; · 3.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: OBJECTIVES: This study was designed to determine the additional clinical value of gait speed to Framingham risk score (FRS), cardiac function and comorbid conditions in predicting cardiovascular events in patients with ST-segment-elevation myocardial infarction (STEMI). BACKGROUND: There is growing evidence that gait speed is inversely associated with all-causes mortality, particularly cardiovascular mortality, among the elderly. METHODS: We undertook a single-center prospective observational study of gait speed in 472 patients with STEMI in Japan, between 2001 and 2008. Gait speeds were measured using 200-meter course before discharge in all patients and we followed cardiovascular events which consist of cardiovascular deaths, non-fatal myocardial infarctions, and non-fatal ischemic strokes. RESULTS: During the 2596 person-years of follow-up, 83 patients (17.6%) experienced cardiovascular events. Cardiovascular events increased across decreasing tertiles of gait speed (fastest tertile: n=5; 3.2%, middle tertile: n=20; 12.6%, slowest tertile: n=58; 36.7%). By multiple adjusted Cox proportional hazards analysis, gait speed was a significant and independent predictor of cardiovascular events (hazard ratio for increasing 0.1m/s of gait speed: 0.71, 95% confidence interval [CI]: 0.63 - 0.81, P<0.001). The addition of gait speed to the model incorporating FRS, B-type natriuretic peptide levels and comorbidity index improved reclassification (Net reclassification index: 32.8%, 95% CI: 17.4 - 48.3, P<0.001) and the C-statistics with a reasonable global fit and calibration (C-statistics [95% CI]: from 0.703 [0.636 - 0.763] to 0.786 [0.738 - 0.829]). CONCLUSION: Among patients with STEMI, slow gait speed was significantly associated with an increased risk of cardiovascular events.
    Journal of the American College of Cardiology 03/2013; · 14.09 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Early transmitral flow velocity (E) divided by early diastolic velocity of the mitral valve annulus (e') is referred to as the E/e' ratio, a variable that strongly correlates with mean left ventricular filling pressure. E/e' obtained at acute phase has been reported as useful in predicting prognosis in patients with acute myocardial infarctions. The aim of this study was to evaluate the clinical utility of echocardiographic indices obtained 2 weeks after the onset of a first ST-segment elevation myocardial infarction as predictors of outcomes. Echocardiography was performed and blood samples were obtained from 301 consecutive patients 2 weeks after the onset of a first ST-segment elevation myocardial infarction. All patients underwent primary percutaneous coronary intervention <12 hours after symptom onset and were followed for 51.7 ± 19.0 months. The primary end point was cardiac death or readmission for heart failure. During follow-up, cardiac death occurred in 10 patients, and heart failure developed in 35. On univariate analysis, age > 75 years, plasma brain natriuretic peptide > 180 pg/mL, early diastolic/late diastolic wave velocity of mitral inflow > 1.0, mitral inflow deceleration time < 140 msec, and E/e' > 15 were associated with the primary end points. Multivariate analysis showed that E/e' > 15 was the strongest predictor (hazard ratio, 3.702; 95% confidence interval, 1.895-7.391; P = .0001), followed by early diastolic/late diastolic wave velocity of mitral inflow > 1.0 (hazard ratio, 3.053; 95% confidence interval, 1.584-6.125; P = .008). Predictive accuracy was further enhanced by combing E/e' > 15 and early diastolic/late diastolic wave velocity of mitral inflow > 1.0 (hazard ratio, 7.373; 95% confidence interval, 3.529-16.528; P < .0001). E/e' > 15 obtained 2 weeks after onset is the strongest predictor of cardiac death and readmission for heart failure after a reperfused first ST-segment elevation myocardial infarction. The predictive value of E/e' at 2 weeks is further enhanced by combining this variable with mitral inflow filling pattern.
    Journal of the American Society of Echocardiography: official publication of the American Society of Echocardiography 12/2012; 25(12):1290-8. · 2.98 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Negative T waves in precordial leads often occur in patients with acute coronary syndrome (ACS), but are also found in acute pulmonary embolism (APE) and Takotsubo cardiomyopathy (TC). Because the clinical features of these two diseases mimic those of ACS, differential diagnosis is essential to select an appropriate treatment strategy improve outcomes. This study aimed to clarify the differences in negative T waves among ACS, APE and TC. We studied admission ECGs in 300 patients (198 patients with ACS caused by the left anterior descending coronary artery disease, 81 with APE and 21 with TC). All patients were admitted within 48 h from symptom onset and had negative T waves ≥1.0 mm without ST-segment elevation in leads V1 to V4. The number and maximal amplitude of negative T waves were greatest in patients with TC, followed by in those with ACS, and were lowest in patients with APE (p < 0.001, respectively). The prevalence of negative T waves significantly differed in all 12 leads among the three groups (p < 0.01, respectively). Negative T waves in both leads III and V1 identified APE with 90% sensitivity and 97% specificity. Negative T waves in lead -aVR (i.e., positive T waves in lead aVR) and no negative T waves in lead V1 identified TC with 95% sensitivity and 97% specificity. These values represented the highest diagnostic accuracies. The distributions of negative T waves differed among ACS, APE and TC, and these differences were useful for differentiating among these three diseases.
    European heart journal. Acute cardiovascular care. 12/2012; 1(4):349-57.
  • [Show abstract] [Hide abstract]
    ABSTRACT: To assess the mechanism of long-term LDL-C-lowering effect of ezetimibe-plus-statin. Coronary artery disease patients whose LDL-C ≥70 mg/dL after treatment with atorvastatin 10 mg/day or rosuvastatin 2.5 mg/day were randomly assigned to receive ezetimibe 10 mg/day + statin (n = 78) or double-dose statin (n = 72) for 52 weeks. Greater LDL-C reduction was observed and maintained until 52 weeks in ezetimibe-plus-statin, while LDL-C levels re-increased after 12 weeks in double-dose statin. Although lathosterol/TC increased, campesterol/TC decreased more in ezetimibe-plus-statin. In contrast, lathosterol/TC unchanged and campesterol/TC increased, increasing campesterol/lathosterol ratio for 52 weeks in double-dose statin. Plasma PCSK9 levels were higher in double-dose statin than in ezetimibe-plus-statin at 12 weeks, but similar at 52 weeks. Although the difference in PCSK9 between 2 groups was transient, that in both campesterol and lathosterol persisted until 52 weeks. These results demonstrated simultaneous inhibition of cholesterol absorption and synthesis provides stable and greater decrease in LDL-C levels.
    Atherosclerosis 08/2012; 224(2):454-6. · 3.71 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In both takotsubo cardiomyopathy (TC) and reperfused anterior acute myocardial infarction (AMI), negative T waves commonly appear on the ECG in the subacute phase. This study aimed to clarify the ECG differences between these diseases. We compared the ECGs with the greatest amplitude of negative T wave from 34 patients with TC and 237 patients with a first reperfused anterior AMI who were admitted within 6 h of symptom onset and who had no abnormal Q-waves on discharge ECG. Time from symptom onset to recording the ECG did not differ between TC and anterior AMI (2.4 ± 1.5 vs. 2.1 ± 2.0 days, P = 0.48). TC was associated with a greater maximal amplitude of negative T wave (1.00 ± 0.44 vs. 0.79 ± 0.46 mV, P = 0.044), and a greater number of leads with negative T waves (9.5 ± 1.0 vs. 6.0 ± 2.1, P<0.001). Negative T waves were consistently observed in leads -aV(R) and V(4-6), whereas negative T waves were rare in lead V(1) in TC. Negative T waves in lead -aV(R) (ie, positive T waves in lead aV(R)) and no negative T waves in lead V(1) identified TC with 94% sensitivity and 95% specificity, representing the highest diagnostic accuracy. During the subacute phase, deeper negative T waves were more frequently and broadly distributed, particularly around leads facing the apical region, in TC than in reperfused anterior AMI.
    Circulation Journal 12/2011; 76(2):462-8. · 3.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The presence and determinants of left ventricular (LV) dyssynchrony in patients with aortic stenosis (AS) are not clear. The aims of this study were to (1) investigate the presence and determinants of LV dyssynchrony and (2) assess if LV dyssynchrony could improve after aortic valve replacement (AVR) in patients with AS with narrow QRS complexes. Twenty healthy subjects and 30 consecutive patients with AS were retrospectively studied. AVR was performed in 19 patients. The time to peak systolic velocity with reference to the QRS complex (Ts), the standard deviation of Ts (Ts-SD), and maximal difference of Ts were measured as the index of LV dyssynchrony in 12 LV segments on Doppler tissue imaging. Ts-SD (25 ± 17 vs 52 ± 15 msec) and the maximal difference of Ts (70 ± 47 vs 148 ± 38 msec) were significantly greater (P < .001) in patients with AS than in healthy subjects. Early after AVR (11 ± 4 days), LV dyssynchrony significantly improved with the shortening of Ts-SD (29 ± 14 msec) and the maximal difference of Ts (91 ± 42 msec) (P < .001). Ts-SD was significantly correlated with estimated LV systolic pressure (r = 0.53, P < .001) and LV mass index (r = 0.28, P = .02). LV dyssynchrony is not uncommon in patients with AS with narrow QRS complexes and is reversible early after AVR, suggesting the favorable effect of afterload reduction on dyssynchronous LV contraction.
    Journal of the American Society of Echocardiography: official publication of the American Society of Echocardiography 12/2011; 24(12):1358-64. · 2.98 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: During inferior acute myocardial infarction, ST-segment elevation (ST↑) often occurs in leads V(5) to V(6), but its clinical implications remain unclear. We examined the admission electrocardiograms from 357 patients with a first inferior acute myocardial infarction who had Thrombolysis In Myocardial Infarction 3 flow of the right coronary artery or left circumflex artery within 6 hours after symptom onset. The patients were divided according to the presence (n = 76) or absence (n = 281) of ST↑ >2 mm in leads V(5) and V(6). Patients with ST↑ in leads V(5) and V(6) were subdivided into 2 groups according to the degree of ST↑ in leads III and V(6): ST↑ in lead III greater than in V(6) (n = 53) and ST↑ in lead III equal to or less than in V(6) (n = 23). The perfusion territory of the culprit artery was assessed using the angiographic distribution score, and a mega-artery was defined as a score of ≥0.7. ST↑ in leads V(5) and V(6) with ST↑ in lead III greater than in V(6) and ST↑ in leads V(5) and V(6) with ST↑ in lead III equal to or less than in V(6) were associated with mega-artery occlusion and impaired myocardial reperfusion, as defined by myocardial blush grade 0 to 1. Right coronary artery occlusion was most common (96%) in the former, and left circumflex artery occlusion was most common (96%) in the latter, especially proximal left circumflex occlusion (74%). Multivariate analysis showed that ST↑ in leads V(5) and V(6) with ST↑ in lead III greater than that in V(6) (odds ratio 4.81, p <0.001) and ST↑ in leads V(5) and V(6) with ST↑ in lead III equal or less than that in V(6) (odds ratio 5.96, p <0.001) were independent predictors of impaired myocardial reperfusion. In conclusion, ST↑ in leads V(5) and V(6) suggests a greater risk area and impaired myocardial reperfusion in patients with inferior acute myocardial infarction. Furthermore, comparing the degree of ST↑ in lead V(6) with that in lead III is useful for predicting the culprit artery.
    The American journal of cardiology 11/2011; 109(3):314-9. · 3.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To assess the role of percutaneous cardiopulmonary support (PCPS) for the resuscitation of patients with massive pulmonary embolism (PE) with circulatory collapse. We also compared outcomes for PCPS between patients with massive PE with circulatory collapse and patients with AMI with cardiogenic shock. The effectiveness of PCPS for acute myocardial infarction (AMI) complicated with cardiogenic shock has been reported, but there are few reports on the use of PCPS for massive PE with circulatory collapse. We studied 12 consecutive patients with massive PE and 16 patients with AMI, who required PCPS for resuscitation either during cardiopulmonary resuscitation (CPR) or after successful CPR. Twelve patients with PE and 16 patients with AMI were identified. There were no differences in age, the Acute Physiology, Age and Chronic Health Evaluation II (APACHE II) score at admission, rate of cardiac arrest on arrival, and time from first circulatory collapse to PCPS between the two groups. However, the proportion of men with PE (33%) was smaller than those with AMI (87%, p<0.05). The duration of PCPS was shorter in PE (38 h) compared with AMI (83 h, p=0.051) patients. The proportion of patients successfully weaned from PCPS (100% vs. 37.5%, p<0.01), survival rate at discharge (83.3% vs. 12.5%, p<0.001) and good neurological outcome (58.3% vs. 6.3%, p=0.004) was significantly higher for PE compared to AMI patients. In our small case series, percutaneous cardiopulmonary support (PCPS) had a life saving role in patients with massive PE and cardiac arrest. PCPS was also more effective in patients with massive PE with cardiac arrest than in patients with AMI and cardiac arrest.
    Resuscitation 11/2011; 83(2):183-7. · 4.10 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Ezetimibe-plus-statin therapy has been reported to provide greater reduction in low-density lipoprotein cholesterol (LDL-C) level than statin monotherapy. The aim of the present study was to evaluate the relationship between LDL-C lowering effect and baseline cholesterol absorption and synthesis markers in patients with coronary artery disease (CAD). A total of 171 patients with CAD whose LDL-C level was ≥ 100 mg/dl after treatment with atorvastatin (10mg/day) or rosuvastatin (2.5 mg/day) for 4 weeks were assigned to additionally receive ezetimibe (10mg/day) plus a statin or a double dose of statin for 12 weeks. The decreases in LDL-C (-30.0 ± 15.6 mg/dl vs. -19.2 ± 14.2 mg/dl) and the ratio of campesterol, an absorption marker, to total cholesterol levels (-1.35 ± 0.90 µg/mg vs. 0.33 ± 0.74 µg/mg) were greater in the ezetimibe-plus-statin group (P<0.05, respectively). The decrease in LDL-C level in the ezetimibe-plus-statin group was greatest in patients with baseline levels of higher absorption and lower synthesis markers and smallest in patients with baseline levels of lower absorption and higher synthesis markers (-34.3 ± 15.6 mg/dl vs. -21.5 ± 16.7 mg/dl, P<0.05). The decrease in LDL-C did not differ, irrespective of baseline levels of cholesterol absorption and synthesis markers, in the double-dose statin group, and was similar to that in patients with lower absorption and higher synthesis markers in the ezetimibe-plus-statin group. Ezetimibe-plus-statin therapy may be useful for lowering LDL-C level, irrespective of baseline levels of cholesterol absorption and synthesis markers.
    Circulation Journal 08/2011; 75(10):2496-504. · 3.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The diagnostic and prognostic value of plasma B-type natriuretic peptide (BNP) level in isolated aortic stenosis (AS) has not been fully understood. BNP level was determined in 109 consecutive patients with isolated severe AS (68.1 ± 10.6 years; 53 men; transvalvular peak gradient, 87.2 ± 37.0 mm Hg; valve area index, 0.43 ± 0.14 cm(2)/m(2)) and 12 healthy volunteers in their stable state. They were followed up for 36 months. BNP level increased with New York Heart Association (NYHA) class (75.2 ± 95.9 pg/mL, 135.0 ± 112.0 pg/mL, 450.6 ± 366.3 pg/mL, and 1478.9 ± 941.5 pg/mL for NYHA I, II, III, and IV, respectively). Left ventricular (LV) mass index had the best relationship with BNP (r = 0.73, P < .0001). Aortic valve replacement (AVR) was eventually performed in 95 patients (male = 44, age = 67.8 ± 9.3 years). Echocardiography was repeated early (n = 88, 13.2 ± 6.2 day) and late (n = 62, 32 ± 10 months) after AVR. Preoperative BNP level correlated with LV mass index early (r = 0.74, P < .0001) and late (r = 0.78, P < .0001) after AVR. Patients with higher BNP level had a tendency to show cardiac symptoms (NYHA > I) late after AVR (NYHA I vs. > I = 160.8 ± 197.9 pg/mL vs. 504.3 ± 567.3 pg/mL, P < .0001). Preoperative BNP level predicted the occurrence of perioperative complications (P < .0001). During follow-up of the 94 patients (44 ± 10 months after AVR), 10 were readmitted for major cardiac and cerebrovascular events, including 9 patients with congestive heart failure and 1 patient with ischemic stroke. An event-free survival rate was significantly higher in patients with BNP ≤ 312 pg/mL than in patients with BNP > 312 pg/mL (log rank, χ(2) = 10.21, P = .001). Multiple logistic regression analysis revealed that BNP > 312 pg/mL was an independent predictor of AVR complication (odds ratio 5.58; confidence interval, 1.82-20.16; P = .002). Furthermore, BNP was the strongest predictor of major adverse cardiac and cerebrovascular events within 36 months after AVR (odds ratio 8.80; confidence interval, 1.83-42.35; P = .006). Plasma BNP level reflects the degree of heart failure, is associated with LV structure and function in severe AS, and is an independent predictor of complication and outcome after AVR. BNP level may be useful in risk stratification of patients with AS in conjunction with other clinical and echocardiographic parameters.
    Journal of the American Society of Echocardiography: official publication of the American Society of Echocardiography 05/2011; 24(9):984-91. · 2.98 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We sought to assess whether hyperinsulinemia is associated with percentage lipid and coronary plaque burden in nondiabetic patients with acute coronary syndromes (ACS). Hyperinsulinemia carries an increased risk of cardiovascular disease even in pre-diabetic patients, but the precise mechanisms of its effects remain unclear. Nonculprit coronary lesions associated with mild-to-moderate stenosis in 82 nondiabetic patients with ACS were examined by integrated backscatter intravascular ultrasound (IB-IVUS), using a 40-MHz intravascular catheter. Conventional IVUS and IB-IVUS measurements from the worst 10-mm segment (1-mm intervals) were calculated. All patients underwent a 75-g oral glucose tolerance test (OGTT) to calculate the area under the insulin concentration-time curve (AUC insulin) from 0 to 120 min. Patients in the high tertile of AUC insulin had a significantly greater percentage lipid area and absolute lipid volume than did patients in the intermediate and low tertiles (tertile 3 vs. tertile 2 vs. tertile 1; 37.6 ± 16.6% vs. 25.8 ± 11.9% vs. 27.5 ± 14.7%, p < 0.01 by analysis of variance [ANOVA], and 29.9 ± 22.6 mm(3) vs. 15.3 ± 12.6 mm(3) vs. 17.7 ± 12.7 mm(3), p < 0.01 by ANOVA, respectively) and a smaller percentage fibrosis area (55.0 ± 11.5% vs. 61.7 ± 9.4% vs. 60.7 ± 9.4%, p = 0.03 by ANOVA). Multiple regression analysis showed that the high tertile of AUC insulin was independently associated with an increased percentage lipid area (p < 0.05). On conventional IVUS analysis, external elastic membrane cross-sectional area was significantly increased with greater plaque volume in patients in the high tertile of AUC insulin (both p < 0.05 by ANOVA). Hyperinsulinemia is associated with an increased lipid content and a greater plaque volume of nonculprit intermediate lesions in nondiabetic patients with ACS, suggesting that plaque vulnerability is increased in this subgroup of patients.
    JACC. Cardiovascular imaging 04/2011; 4(4):392-401. · 14.29 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Although there has been an intense debate whether concomitant use of proton-pump inhibitors (PPIs) attenuates the antiplatelet effects of thienopyridine derivatives, the drug-drug interaction remains unclear in Japanese patients with coronary artery disease. Platelet function test was performed in 461 patients who were scheduled for or had undergone stent implantation, treated with 100mg/day of aspirin and a thienopyridine (200mg/day of ticlopidine or 75 mg/day of clopidogrel) for at least 14 days. Adenosine diphosphate-induced platelet aggregation was evaluated with screen filtration pressure method, and the upper quartile of high platelet reactivity was defined as high on-treatment platelet reactivity (HPR). PPI use was at physician's discretion. Patients taking a thienopyridine plus a PPI (n=166) were older and had a higher incidence of acute coronary syndromes on admission compared with patients taking a thienopyridine without a PPI (n=295). The rate of HPR was higher in patients taking a thienopyridine plus a PPI than in patients taking a thienopyridine without a PPI (31% vs 21%, p=0.01). On multivariate logistic regression analysis, independent predictors of HPR were concomitant PPI use [odds ratio (OR): 1.66, 95% confidence interval (CI): 1.03-2.68], diabetes mellitus (OR: 1.76, CI: 1.11-2.81), and calcium channel blockers use (OR: 1.93, CI: 1.18-3.18). However, there was no significant difference in the rate of extremely high platelet reactivity [58 patients (12.5%) with PATI<4.0 μM] between patients treated with a thienopyridine plus a PPI and those without a PPI (14% vs 11%, NS). HPR was frequently observed in Japanese patients treated with thienopyridines plus PPIs compared to those without PPIs. Further prospective studies are needed to estimate the risk of adverse cardiovascular events associated with concomitant use of PPIs and thienopyridines.
    Journal of Cardiology 03/2011; 57(3):275-82. · 2.30 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Clopidogrel should be initiated as soon as possible in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) except those who urgently require coronary artery bypass grafting (CABG). The present study assessed the ability to predict severe left main coronary artery and/or 3-vessel disease (LM/3VD) that would most likely require urgent CABG based on only clinical factors on admission in 572 patients with NSTE-ACS undergoing coronary angiography. Severe LM/3VD was defined as ≥75% stenosis of LM and/or 3VD with ≥90% stenosis in ≥2 proximal lesions of the left anterior descending coronary artery and other major epicardial arteries. Patients were divided into the 3 groups according to angiographic findings: no LM/3VD (n = 460), LM/3VD but not severe LM/3VD (n = 57), and severe LM/3VD (n = 55). Severe LM/3VD was associated with a higher rate of urgent CABG compared to no LM/3VD and LM/3VD but not severe LM/3VD (46%, 2%, and 2%, p <0.001). On multivariate analysis, degree of ST-segment elevation in lead aVR was the strongest predictor of severe LM/3VD (odds ratio 29.1, p <0.001), followed by positive troponin T level (odds ratio 1.27, p = 0.044). ST-segment elevation ≥1.0 mm in lead aVR best identified severe LM/3VD with 80% sensitivity, 93% specificity, 56% positive predictive value, and 98% negative predictive value. In conclusion, ST-segment elevation ≥1.0 mm in lead aVR on admission electrocardiogram is highly suggestive of severe LM/3VD in patients with NSTE-ACS. Selected patients with this finding might benefit from promptly undergoing angiography, withholding clopidogrel to allow early CABG.
    The American journal of cardiology 02/2011; 107(4):495-500. · 3.58 Impact Factor
  • Journal of The American College of Cardiology - J AMER COLL CARDIOL. 01/2011; 57(14).

Publication Stats

230 Citations
161.56 Total Impact Points

Institutions

  • 2006–2014
    • Yokohama City University
      Yokohama, Kanagawa, Japan
  • 2013
    • Kumamoto University
      • Department of Cardiovascular Medicine
      Kumamoto-shi, Kumamoto Prefecture, Japan
  • 2010–2011
    • Numazu City Hospital
      Sizuoka, Shizuoka, Japan
  • 2005–2011
    • National Cerebral and Cardiovascular Center
      • Department of Cardiovascular Medicine
      Ōsaka, Ōsaka, Japan