Masaaki Kanashiro

Yokkaichi Municipal Hospital, Yokkaiti, Mie, Japan

Are you Masaaki Kanashiro?

Claim your profile

Publications (16)64.94 Total impact

  • Journal of Cardiac Surgery 06/2014; · 1.35 Impact Factor
  • International journal of cardiology 07/2013; · 6.18 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Recently, neoatherosclerosis within the neointima after bare metal stent (BMS) implantation, which could cause late restenosis and very late stent thrombosis, has been a cause of concern. Renal dysfunction has been related to late cardiovascular events after coronary intervention. The present study was conducted focusing on the relationship between renal dysfunction and neointimal tissue characteristics with BMS restenosis using integrated backscatter intravascular ultrasound (IB-IVUS). Methods: We prospectively performed IB-IVUS in 80 consecutive patients requiring target lesion revascularization after BMS implantation; the patients were divided into two groups according to the estimated glomerular filtration [eGFR: ≥60 (n = 49) and <60 ml/min/1.73 m(2) (n = 31)]. Results: Patients with eGFR <60 ml/min/1.73 m(2) had a significantly higher percentage of lipid tissue volume within the neointima and a lower percentage of fibrous tissue volume than those with eGFR ≥60 ml/min/1.73 m(2) (23.2 ± 9.4 vs. 18.0 ± 7.0%, p = 0.005, and 75.3 ± 9.3 vs. 80.4 ± 7.0%, p = 0.007, respectively). Using logistic regression analysis, eGFR <60 ml/min/1.73 m(2) and duration from stent implantation ≥48 months were independent predictors of increased lipid tissue volume within the neointima (odds ratio, 3.93; 95% confidence interval, 1.15-13.46, p = 0.03, and odds ratio, 7.56; 95% confidence interval, 2.02-28.30, p = 0.003, respectively). Conclusions: Lower eGFR levels were associated with greater lipid tissue volume within the neointima after BMS deployment, suggesting the development of atherosclerosis. Renal dysfunction may affect neointimal tissue characteristics and thus leading to an increased risk of late stent failure.
    American Journal of Nephrology 07/2013; 38(1):58-65. · 2.62 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Coronary plaques can be reduced by some medications. The aim of this study was to compare the effects of 2 angiotensin II receptor blockers (olmesartan at 20 mg/day or valsartan at 80 mg/day) on coronary plaque by coronary intravascular ultrasound. One hundred hypertensive patients with stable angina pectoris who underwent elective percutaneous coronary intervention were randomly selected to receive 1 of the 2 angiotensin II receptor blockers after coronary intervention. Nontarget coronary lesions with mild to moderate stenosis were measured by volumetric intravascular ultrasound at baseline and after 6 months. After 6 months, both the olmesartan and the valsartan groups showed significant reduction of the examined coronary plaque volume (46.2 ± 24.1 mm(3) at baseline vs 41.6 ± 21.1 mm(3) at 6 months: 4.7% decrease, p = 0.0002; and 47.2 ± 32.7 mm(3) at baseline vs 42.5 ± 30.2 mm(3) at 6 months: 4.8% decrease, p = 0.002, respectively). There was no statistically significant difference of plaque regression between the 2 groups (p = 0.96). In conclusion, there was a significant decrease from baseline in the coronary plaque volume in patients with stable angina pectoris who received olmesartan or valsartan for 6 months. In addition, there was no significant difference in the reduction of plaque volume achieved by these 2 medications.
    The American journal of cardiology 04/2013; · 3.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Microvascular impairment is associated with a poor prognosis even after successful percutaneous coronary intervention (PCI) in acute myocardial infarction. The aim of the present study was to examine the impact of metabolic syndrome (MetS) on various aspects of microvascular function and clinical outcomes. In 216 consecutive patients with ST-segment elevation myocardial infarction (STEMI) after successful primary PCI, data were collected and analyzed on epicardial coronary flow, ST-segment resolution (STR) on electrocardiography, maximum serum creatine kinase levels, and the incidence of major adverse cardiac events (MACE). The prevalence of MetS was 40.7% (88 patients). Corrected Thrombolysis In Myocardial Infarction frame count was significantly higher in the MetS group than in the non-MetS group (28.1±9.4 vs. 24.7±7.9, P=0.04). STR ≥50% was observed in 51.1% and 69.5%, respectively (P=0.01). Patients with MetS also had higher maximum creatine kinase levels (3,470±2,320IU/L vs. 2,664±1,850IU/L, P=0.01). On logistic regression analysis after adjustment for confounders, MetS was an independent negative predictor of complete STR (odds ratio, 0.49; 95% confidence interval [CI]: 0.25-0.95, P=0.03). On Cox multivariate analysis, MetS was an independent predictor for MACE (hazard ratio, 4.85; 95% CI: 1.28-18.3, P=0.02). MetS may damage microcirculation after direct PCI in patients with STEMI and lead to poor prognosis.
    Circulation Journal 05/2012; 76(8):1972-9. · 3.58 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A variety of structural cardiovascular abnormalities have been implicated in deaths of athletes, particularly congenital coronary arteries of anomalous origin, which are rare but major causes of myocardial ischemia and sudden death in young people. We present here the case of a rare congenital coronary artery anomaly in a 16-year-old boy who suffered from acute myocardial infarction due to occlusion of the left main trunk coronary artery, providing specific intravascular ultrasound findings for this anomaly.
    Journal of Cardiology Cases 02/2012; 5(1):e55–e57.
  • [Show abstract] [Hide abstract]
    ABSTRACT: It is well known that chronic kidney disease is a risk factor for atherosclerosis. The present study was conducted to identify any relation between the estimated glomerular filtration rate (eGFR) and coronary plaque characteristics using integrated backscatter intravascular ultrasound (IB-IVUS), which can detect coronary plaque composition. We performed IB-IVUS for 201 consecutive patients undergoing percutaneous coronary intervention, and they were divided into 3 groups according to the eGFR values (group 1 [n = 20], ≥90 ml/min/1.73 m(2); group 2 [n = 123], 60 to 90 ml/min/1.73 m(2); and group 3 [n = 58], <60 ml/min/1.73 m(2)). Coronary plaques in nonculprit lesions on 3-dimensional analysis were evaluated using IB-IVUS. The baseline characteristics were similar, except for older age and a greater prevalence of men in group 3. IB-IVUS showed a percentage of lipid volume of 44.7 ± 5.0% in group 1, 53.6 ± 6.2% in group 2, and 63.5 ± 6.2% in group 3 (p <0.01), with a corresponding percentage of fibrous volume of 53.9 ± 4.9%, 45.1 ± 6.0%, and 35.3 ± 6.1%, respectively (p <0.01). The eGFR correlated significantly with both parameters (r = -0.68, p <0.001 and r = 0.68, p <0.001, respectively). In conclusion, lower eGFR levels were associated with greater lipid and lower fibrous contents, contributing to coronary plaque vulnerability.
    The American journal of cardiology 01/2012; 109(8):1131-6. · 3.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The left main coronary artery (LMCA) is a particularly important target of atherosclerotic plaque accumulation. The aim of this study was to investigate the connection between subclinical plaque burden in the LMCA measured by intravascular ultrasound and future cardiovascular events. Two hundred eighteen consecutive patients underwent percutaneous coronary intervention for the left anterior descending coronary artery or the left circumflex coronary artery under intravascular ultrasound guidance. Plaque burden in the LMCA was analyzed for these patients, and major adverse cardiac events were also evaluated. Data were analyzed by grouping the patients into tertiles according to plaque burden values; tertile 1, <32% area stenosis; tertile 2, 32% to 45% area stenosis; and tertile 3, >45% area stenosis. During a 3-year follow-up period (average 16.1 months), 12% of tertile 1, 18% of tertile 2, and 40% of tertile 3 experienced major adverse cardiac events, mostly due to repeat revascularization (p <0.001). On Cox multivariate analysis, plaque burden in the LMCA (per percentage) detected by intravascular ultrasound remained an independent significant predictor of major adverse cardiac events (hazard ratio 1.04, 95% confidence interval 1.02 to 1.07) and future revascularization (hazard ratio 1.05, 95% confidence interval 1.02 to 1.07) (p <0.001). In conclusion, plaque burden in the LMCA is useful as an indicator of coronary atherosclerosis and may be a significant predictor of cardiovascular events, especially revascularization.
    The American journal of cardiology 11/2011; 109(3):352-8. · 3.58 Impact Factor
  • Journal of The American College of Cardiology - J AMER COLL CARDIOL. 01/2011; 57(14).
  • [Show abstract] [Hide abstract]
    ABSTRACT: The Japan assessment of pitavastatin and atorvastatin in acute coronary syndrome (JAPAN-ACS) study demonstrated that aggressive lipid-lowering therapy with a statin resulted in a significant regression of coronary atherosclerotic plaques in patients with ACS. Adiponectin is an adipocyte-derived protein with anti-atherogenic properties. Here, we investigated the association between adiponectin levels and the change in the plaque volume in ACS patients. Intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) was undertaken, followed by the initiation of statin treatment, in 238 patients with ACS. Follow-up IVUS was performed between 8 and 12 months after the PCI. The percent change in the plaque volume (%PV) in a non-culprit coronary artery segment was evaluated. The serum adiponectin and lipid parameters were measured both at baseline and at the follow-up. At baseline, adiponectin was correlated positively with HDL-cholesterol and negatively correlated with triglyceride, but no correlation was observed with the PV. Adiponectin levels increased significantly from 7.8+/-4.6 microg/mL at baseline to 10.3+/-6.9 microg/mL at the 8-12 months follow-up. The increase in adiponectin was also associated with an increase of HDL-cholesterol and decrease of triglyceride, however, no significant correlation was observed with the %PV. A significantly higher incidence of major adverse cardiac events (MACE) was observed in patients with hypo-adiponectinemia at baseline. A multiple logistic regression analysis identified adiponectin as a significant independent predictor of MACE. Adiponectin levels measured after PCI could serve as a marker of MACE in patients with ACS.
    Atherosclerosis 09/2010; 212(1):237-42. · 3.71 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Published reports have indicated that prodromal angina before acute myocardial infarction (AMI) is associated with better outcomes and that nicorandil has cardioprotective effects on ischemic hearts. We compared cardioprotective effects of intravenous nicorandil with preconditioning effects by prodromal angina in patients with AMI who underwent percutaneous coronary intervention (PCI). In total, 368 patients with first ST-elevation AMI who underwent PCI were randomly assigned to receive nicorandil 12 mg or a placebo intravenously just before PCI. Subjects were assigned to 1 of 4 groups: 52 patients with prodromal angina were given placebo, 129 patients without prodromal angina were given nicorandil, 56 patients with prodromal angina were given nicorandil, and 131 patients without prodromal angina were given placebo. Coronary microvascular impairment after PCI was prevented at similar frequencies in groups with prodromal angina and groups on nicorandil. Five-year rates for freedom from major cardiac events were similar across groups with prodromal angina given placebo, without prodromal angina given nicorandil, and with prodromal angina given nicorandil (92.3%, 93.8%, and 92.9%, respectively) but were significantly lower in the group without prodromal angina given placebo (80.2%, p = 0.0019, 0.044, and 0.042, respectively). In conclusion, intravenous administration of nicorandil before PCI exerts pharmacologic cardioprotective effects similar to ischemic preconditioning in patients with AMI.
    The American Journal of Cardiology 06/2007; 99(9):1203-7. · 3.21 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Patients receiving hemodialysis for end-stage renal disease (ESRD) are at high risk for death from ischemic heart disease (IHD). Nicorandil, a hybrid compound of adenosine triphosphate-sensitive potassium channel opener and nitric oxide donor, has been reported to improve the clinical prognosis of patients with IHD. This study sought to investigate the efficacy of oral nicorandil in reducing the risks for cardiovascular events (CVEs) and CVE-related death in patients receiving hemodialysis for ESRD after undergoing percutaneous coronary intervention (PCI) for angina pectoris. For this retrospective chart review, we used data from telephone interviews and medical charts from 3 hospitals in Japan. Data from patients aged <80 years who were receiving hemodialysis for ESRD and who had undergone successful PCI for angina between January 1999 and December 2004 were included in the analysis. Patients were stratified based on status of nicorandil treatment before PCI, as follows: patients receiving nicorandil 5 mg PO TID (the recommended dosage in Japan) for >1 month before PCI (nicorandil group) or those who did not receive nicorandil (control group). We investigated 6-year follow-up data on the primary end point, defined as CVEs (ie, unplanned hospital admission for worsening anginal status, or CVE-related death). The secondary end point was CVE-related death. After the data were initially analyzed, we performed a propensity-matched analysis to minimize selection bias. Data from 356 patients were included in the study (235 men, 121 women; mean [SD] age, 69 [9] years; mean [SD] weight, 52.3 [9.1] kg; nicorandil group, 198 patients; control group, 158 patients). According to the estimated propensity scores, 107 patients from each group were matched. There were no differences between the 2 groups in the baseline characteristics. On propensity-matched patient analysis, the estimated rates of patients who were CVE-free at 6 years were 33.5% in the nicorandil group and 21.8% in the control group on Kaplan-Meier analysis (hazard ratio [HR] = 0.53; 95% CI, 0.36-0.78; P < 0.002), and the rates of 6-year survival (ie, patients who did not experience CVE-related death) were 92.7% in the nicorandil group and 85.8% in the control group (HR = 0.27; 95% CI, 0.07-0.89; P = 0.047). Cox multivariate analysis found that nico-randil treatment status was an independent predictor of CVEs (HR = 0.40; 95% CI, 0.18-0.91; P = 0.028) and CVE-related death (HR = 0.38; 95% CI, 0.14-0.78; P = 0.030). Results obtained in this retrospective study suggest the potential efficacy of nicorandil treatment in improving clinical outcomes in patients with IHD receiving hemodialysis following PCI.
    Clinical Therapeutics 02/2007; 29(1):110-22. · 2.23 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Studies have reported an association between receipt of statin therapy and a reduction in complications after elective percutaneous coronary intervention (PCI). However, there are limited data on the effects of chronic statin therapy before the occurrence of an acute myocardial infarction (AMI). This study investigated whether administration of chronic statin therapy before AMI was associated with a reduction in reperfusion injury in AMI patients undergoing PCI. This was a retrospective study of consecutive patients with a first AMI who underwent successful reperfusion therapy with PCI within 24 hours after the onset of AMI between April 1998 and October 2003. Patients were stratified according to whether they had or had not been receiving chronic statin therapy for > or = 1 month before the onset of AMI. The following end points were compared after PCI: electrocardiographic resolution of ST segment elevation, defined as a reduction of > or = 50% from the initial value; achievement of Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow; corrected TIMI frame count (cTFC); maximum serum creatine kinase (CK) level; and the type and frequency of ventricular arrhythmias. The study enrolled 386 patients, 40 of whom had been receiving statin therapy before the onset of AMI. The clinical characteristics of the 2 groups were similar at baseline, with the exceptions of a significantly higher rate of hyperlipidemia in the statin group compared with the nonstatin group (P < 0.001), significantly greater chronic use of aspirin therapy (P < 0.001), and significantly greater chronic use of antihypertensive medications (beta-blockers: P = 0.004; angiotensin-converting enzyme inhibitors/angiotensin II-receptor blockers: P = 0.007; calcium channel blockers: P = 0.006). Electrocardiographic ST segment resolution after PCI was observed in 87.5% and 69.9% of the statin and nonstatin groups, respectively (hazard ratio [HR]: 3.01; 95% CI, 1.15-7.90; P = 0.025). Achievement of TIMI grade 3 flow after PCI was seen in 95.0% of the statin group and 83.5% of the nonstatin group (HR: 3.75; 95% CI, 0.88-16.0; P = NS). Patients treated with a statin had a significantly lower mean (SD) maximum CK level compared with the nonstatin group (2300 [1449] vs 3538 [3170] IU/mL, respectively; P = 0.015) and a lower cTFC after PCI (18.8 [4.0] vs 24.2 [14.2]; P = 0.017). The difference in reperfusion arrhythmias between groups was not statistically significant. After adjustment for baseline covariates, pretreatment with a statin was found to be an independent predictor of ST segment resolution after PCI (HR: 2.95; 95% CI, 1.08-8.09; P = 0.035) and prevention of impaired coronary flow (HR: 3.00; 95% CI, 1.63-5.55; P < 0.001). In this study, receipt of chronic statin therapy before the onset of AMI was associated with improvement in epicardial perfusion and a reduction in myocardial necrosis after PCI.
    Clinical Therapeutics 11/2006; 28(11):1812-9. · 2.23 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Stress hyperglycemia increases the risk of mortality and poor outcomes in patients with acute myocardial infarction (AMI). We aimed to assess effects of intravenous nicorandil administered before reperfusion on AMI patients with stress hyperglycemia. This study consisted of 158 consecutive first AMI patients with stress hyperglycemia who underwent percutaneous coronary intervention (PCI) within 24 h from the onset. They were randomly assigned to receive 12 mg of nicorandil (n = 81) or a placebo (n = 77) intravenously just before reperfusion. Stress hyperglycemia was defined as a blood glucose level > or =10 mmol/l (180 mg/dl). We examined various aspects of epicardial flow and microvascular function as immediate data and major adverse cardiac events (MACEs) (coronary heart disease death or unplanned readmission due to congestive heart failure) as late-phase data. The incidence of slow flow after PCI was lower in the nicorandil group (13.6 vs. 27.3%, P < 0.04). ST segment resolution >50% was observed in 70.4 and 53.2% on nicorandil and placebo, respectively (P < 0.03). Patients treated with nicorandil had a lower peak creatine kinase level (3,137 +/- 2,577 vs. 4,333 +/- 3,608, P < 0.02). Upon Kaplan-Meier analysis, 5 years' freedom from MACEs was 86.4% in the nicorandil group and 74.0% in the placebo (P < 0.05). Adjunctive therapy with administration of intravenous nicorandil before reperfusion on AMI patients with stress hyperglycemia significantly improves epicardial flow and prevents the occurrence of severe microvascular reperfusion injury, resulting in better outcomes in these patients.
    Diabetes Care 02/2006; 29(2):202-6. · 7.74 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Intravenous nicorandil, a hybrid compound of ATP-sensitive potassium channel opener and nitric oxide donor, has been reported to ameliorate early functional and clinical problems in patients with acute myocardial infarction. However, its effects on the late phase remain unclear. This follow-up study to 5 years of a randomized, double-blinded trial was conducted among 368 patients with first ST-segment-elevation myocardial infarction undergoing percutaneous coronary intervention (PCI). They were randomly assigned to receive 12 mg of nicorandil or a placebo intravenously just before reperfusion. We analyzed incidence of cardiovascular death or rehospitalization for congestive heart failure after PCI as well as various aspects of epicardial flow and microvascular function. Mean follow-up was 2.4 years (SD, 1.4). A total of 12 (6.5%) patients receiving nicorandil and 30 (16.4%) receiving placebo had cardiovascular death or hospital admission for congestive heart failure (hazard ratio, 0.39; 95% CI, 0.20 to 0.76; P=0.0058). Postprocedural TIMI 3 flow was obtained in 89.7% of the nicorandil group and in 81.4% of the placebo (hazard ratio, 1.99; 95% CI, 1.09 to 3.65; P=0.025). Corrected TIMI frame count was furthermore lower in the nicorandil group (21.0+/-9.1 versus 25.1+/-14.1; P=0.0009). ST-segment resolution >50% was observed in 79.5% and 61.2% of the nicorandil and placebo groups, respectively (hazard ratio, 2.45; 95% CI, 1.54 to 3.90; P=0.0002). The addition of intravenous nicorandil to PCI leads to beneficial clinical outcomes and prevents cardiovascular events of long duration and death in patients with ST-segment-elevation myocardial infarction.
    Circulation 08/2005; 112(9):1284-8. · 15.20 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Modification of rotational atherectomy (RA) procedures might be expected to alter restenosis rates. From June 1998 (period 2), platform speed was decreased to 150,000-160,000 rpm from the 170,000-190,000 rpm performed from August 1997 to May 1998 (period 1). Patients for the two periods (period 1: 62 patients, 70 lesions; period 2: 85 patients, 91 lesions) demonstrated comparable clinical and angiographic baseline data, allowing immediate and late outcomes to be evaluated for comparison. Restenosis rates in periods 1 and 2 were 57.9% and 33.8%, respectively (P=0.01). Platform speed and lesion length were independent predictors of restenosis by multivariate logistic regression analysis. RA with a low platform speed (150,000-160,000 rpm) can be performed with a high success rate and with a lower incidence of restenosis than with a high platform speed (170,000-190,000 rpm).
    International Journal of Cardiology 04/2004; 94(1):35-40. · 6.18 Impact Factor