Hiroaki Watabe

Impact of coronary plaque composition on cardiac troponin elevation after percutaneous coronary intervention in stable angina pectoris: a computed tomography analysis.

OBJECTIVES The authors used multidetector computed tomography (MDCT) to study the relation between culprit plaque characteristics and cardiac troponin T (cTnT) elevation after percutaneous coronary intervention (PCI). BACKGROUND Percutaneous coronary intervention is often complicated by post-procedural myocardial necrosis manifested by elevated cardiac biomarkers. METHODS Stable angina patients (n = 107) with normal pre-PCI cTnT levels underwent 64-slice MDCT before PCI to evaluate plaque characteristics of culprit lesions. Patients were divided into 2 groups according to presence (group I, n = 36) or absence (group II, n = 71) of post-PCI cTnT elevation ≥3 times the upper limit of normal (0.010 ng/ml) at 24 h after PCI. RESULTS Computed tomography attenuation values were significantly lower in group I than in group II (43.0 [26.5 to 75.7] HU vs. 94.0 [65.0 to 109.0] HU, p < 0.001). Remodeling index was significantly greater in group I than in group II (1.20 ± 0.18 vs. 1.04 ± 0.15, p < 0.001). Spotty calcification was observed significantly more frequently in group I than in group II (50% vs. 11%, p < 0.001). Multivariate analysis showed presence of positive remodeling (remodeling index >1.05; odds ratio: 4.54; 95% confidence interval: 1.36 to 15.9; p = 0.014) and spotty calcification (odds ratio: 4.27; 95% confidence interval: 1.30 to 14.8; p = 0.016) were statistically significant independent predictors for cTnT elevation. For prediction of cTnT elevation, the presence of all 3 variables (CT attenuation value <55 HU; remodeling index >1.05, and spotty calcification) showed a high positive predictive value of 94%, and their absence showed a high negative predictive value of 90%. CONCLUSIONS MDCT may be useful in detecting which lesions are at high risk for myocardial necrosis after PCI.

Association of contrast-induced acute kidney injury with long-term cardiovascular events in acute coronary syndrome patients with chronic kidney disease undergoing emergent percutaneous coronary intervention☆

BACKGROUND The association between contrast-induced acute kidney injury (CI-AKI) and chronic kidney disease (CKD) in patients with acute coronary syndrome (ACS) treated with percutaneous coronary intervention (PCI) has not been fully reported. We evaluated the association of CI-AKI on cardiovascular events in ACS patients with CKD. METHODS A total of 1059 ACS patients who underwent emergent PCI in our multicenter registry were enrolled (69±12 years, 804 men, 604 STEMI patients). CKD was defined as at least stage 3 CKD, and CI-AKI was defined as an increase of at least 0.5 mg/dL and/or an increase of at least 25% of pre-PCI to post-PCI serum creatinine levels within 1 week after the procedure. Primary endpoints included cardiovascular death, myocardial infarction, and cerebrovascular disorder (stroke or transient ischemic attack). RESULTS In our study, 368 (34.7%) patients had CKD. During follow-up periods (435±330 days), CI-AKI and primary endpoints occurred in 164 (15.5%) patients and 106 (10.0%) patients, respectively. Multivariate Cox proportional hazards model revealed that age, female gender, peak creatinine kinase>4000, IABP use, CI-AKI (hazard ratio [HR], 2.17; 95% confidential interval [CI], 1.52 to 4.00; P<0.001), and CKD (HR, 1.66; 95% CI, 1.01 to 2.72; P=0.046) were independent predictors of primary endpoints. Kaplan-Meier analysis showed that occurrence of primary endpoints increased significantly with an increase in CKD stage, and CI-AKI yielded worse long-term prognosis at every stage of CKD (P<0.001). CONCLUSIONS CI-AKI was revealed to be a significant incremental predictor of cardiovascular events at each stage of CKD in ACS patients.

Prognostic Value of Myocardial Contrast Delayed Enhancement With 64-Slice Multidetector Computed Tomography After Acute Myocardial Infarction

OBJECTIVES This study evaluated the clinical value of myocardial contrast delayed enhancement (DE) with multidetector computed tomography (MDCT) for predicting clinical outcome after acute myocardial infarction (AMI). BACKGROUND Although some studies have described the use of MDCT for assessment of myocardial viability after AMI, clinical experience remains limited. METHODS In 102 patients with first AMI, 64-slice MDCT without iodine reinjection was performed immediately following successful percutaneous coronary intervention (PCI). We measured the size of myocardial contrast DE on MDCT and compared it with clinical outcome. Primary composite cardiac events were cardiac death or hospitalization for worsening heart failure. RESULTS Among the 102 patients (24 ± 10 months follow-up), 19 patients experienced primary composite cardiac events (cardiac death, n = 7; heart failure, n = 12). Kaplan-Meier analysis showed higher risk of cardiac events for patients in the third tertile of myocardial contrast DE size (≥ 36 g) than for those in the other 2 tertiles (p < 0.0001). Multivariable Cox proportional hazards regression analysis indicated that myocardial contrast DE size (adjusted hazard ratio [HR] for tertile 3 vs. 1: 16.1, 95% confidence interval [CI]: 1.45 to 72.4, p = 0.022; HR for tertile 3 vs. 2: 5.06, 95% CI: 1.25 to 22.7, p = 0.039) was a significant independent predictor for cardiac events after adjustment for Thrombolysis In Myocardial Infarction risk score, left ventricular ejection fraction, total defect score on single-photon emission CT with technetium tetrofosmin, and transmural extent of myocardial contrast DE on MDCT. CONCLUSIONS Myocardial contrast DE size on MDCT immediately after primary PCI may provide promising information for predicting clinical outcome in patients with AMI.

Preventive effect of statin pretreatment on contrast-induced acute kidney injury in patients undergoing coronary angioplasty: Propensity score analysis from a multicenter registry

BACKGROUND The prophylactic benefit of statins in reducing the incidence of contrast-induced acute kidney injury (CI-AKI) has been investigated in several studies with conflicting results. We sought to investigate whether statin pretreatment prevents CI-AKI in coronary artery disease (CAD) patients undergoing percutaneous coronary intervention (PCI). METHODS A total of 2198 CAD patients who underwent PCI, except for those undergoing dialysis or who died within 7 days after angioplasty, were analyzed from the ICAS (Ibaraki Cardiovascular Assessment Study) multicenter registry. Analyzed subjects were divided into 2 groups according to statin pretreatment: statin pretreatment (n=839) and non-statin pretreatment (n=1359). Selection bias of statin pretreatment was adjusted by propensity score-matching method: pretreatment statin (n=565) and non-statin pretreatment (n=565). CI-AKI was defined as an increase in serum creatinine of ≥ 25% or 0.5mg/dl from baseline within 1 week of contrast medium exposure. RESULTS A total of 192 (8.7%) patients developed CI-AKI. No significant differences were observed in baseline patient characteristics between the statin and non-statin pretreatment groups after propensity score matching. In the propensity score-matched groups, the incidence of CI-AKI was significantly lower in patients with statin pretreatment than in those without statin pretreatment (3.5% vs.10.6%, odds ratio [OR]: 0.31, 95% confidence interval [CI]: 0.18-0.52, P<0.001). Multivariate logistic regression analysis showed that statin pretreatment remained an independent negative predictor of CI-AKI (OR: 0.31, 95% CI: 0.18-0.53, P<0.001) among propensity score-matched subjects. CONCLUSIONS Statin pretreatment was associated with a significant decrease in the risk of CI-AKI in CAD patients undergoing PCI in the ICAS Registry.

Effect of individual proton pump inhibitors on cardiovascular events in patients treated with clopidogrel following coronary stenting: results from the Ibaraki Cardiac Assessment Study Registry.

Objectives: The aim of this study was to evaluate whether combination therapy of clopidogrel and proton pump inhibitors (PPIs) causes higher numbers of cardiovascular events than clopidogrel alone in Japanese patients. Background: PPIs are often prescribed in combination with clopidogrel following coronary stenting. PPIs are reported to diminish the effect of clopidogrel because both are metabolized by CYP2C19. However, no reports address the effects of PPIs on cardiovascular events following coronary stenting in the Japanese population. Methods: A total of 1,887 patients treated with clopidogrel following coronary stenting were enrolled in the Ibaraki Cardiac Assessment Study (ICAS) registry. All subjects were classified into two groups according to treatment without (n = 819) or with (n = 1,068) PPI. Propensity score analysis matched 1:1 according to treatment without PPI (n = 500) or with PPI (n = 500). Primary endpoint was the composite of all‐cause death or myocardial infarction. Results: No significant difference was observed in the primary endpoint between the group without PPI and the group with PPI (4.6% vs. 4.6%, P = 0.77). In contrast, a significant difference was found between the group without PPI and with PPI in regard to the incidence of gastrointestinal bleeding at the end of the follow‐up period and the specific PPI prescribed (2.4% vs. 0.8%, adjusted HR = 0.30, 95% Confidence interval 0.08‐0.87, P = 0.026) after propensity score matching. Conclusions: No significant association between PPI use and primary endpoint was observed in the Japanese population, whereas PPI use resulted in a significant reduction in the rate of gastrointestinal bleeding.

Gender differences in the association between serum uric acid and prognosis in patients with acute coronary syndrome

BACKGROUND Increased levels of uric acid (UA) have been associated with cardiovascular disease. This association is generally stronger in women than men. However, gender differences in the prognostic value of UA in patients with acute coronary syndrome (ACS) are unknown. We investigated gender differences in the relationship between UA level and the prognosis in patients with ACS. METHOD This was an observational analysis of patients with ACS undergoing percutaneous coronary intervention enrolled in the Ibaraki Cardiac Assessment Study (ICAS) registry. We analyzed 1380 patients (330 women, 1050 men) with ACS who had information on UA. We assessed the association between UA and the incidence of major cardiovascular adverse events (MACE), defined as all-cause death, congestive heart failure, reinfarction, and stroke. Patients were divided according to gender-specific UA quartile. RESULTS The mean UA level in women was significantly lower than that in men (4.9mg/dl vs 5.9mg/dl, p<0.001). After a median duration of follow-up period of 437 days (interquartile range 222-801 days), MACE had occurred in 186 (13%) patients [56 (17%) events in women; 130 (12%) events in men]. Kaplan-Meier analysis for MACE-free survival demonstrated that a higher quartile of UA was associated with MACE in both women and men (p<0.001, p=0.002, respectively). Multivariate Cox regression analysis revealed that the highest quartile of UA, as compared with the lowest quartile of UA, was an independent predictor of MACE in women [hazard ratio (HR), 2.84; 95% CI, 1.19-6.77; p=0.018] but not in men (HR, 1.32; 95% CI, 0.66-2.64; p=0.422). CONCLUSIONS An increased level of UA was associated with MACE more strongly in women than in men with ACS. These results suggest that there are gender differences in the association of UA level with the prognosis in patients with ACS.

Enhancement patterns detected by multidetector computed tomography are associated with microvascular obstruction and left ventricular remodelling in patients with acute myocardial infarction

AIMS This study evaluated the clinical value of myocardial contrast-delayed enhancement (DE) with multidetector computed tomography (MDCT) for detecting microvascular obstruction (MVO) and left ventricular (LV) remodelling revealed by DE magnetic resonance imaging after acute myocardial infarction (AMI). METHODS AND RESULTS In 92 patients with first AMI, MDCT without iodine reinjection was performed immediately following successful percutaneous coronary intervention (PCI). Delayed-enhancement magnetic resonance imaging performed in the acute and chronic phases was used to detect MVO and LV remodelling (any increase in LV end-systolic volume at 6 months after infarction compared with baseline). Patients were divided into two groups according to the presence (n = 33) or absence (n = 59) of heterogeneous enhancement (HE). Heterogeneous enhancement was defined as concomitant presence of hyper- and hypoenhancement within the infarcted myocardium on MDCT. Microvascular obstruction and LV remodelling were detected in 49 (53%) and 29 (32%) patients, respectively. In a multivariable analysis, HE and a relative CT density >2.20 were significant independent predictors for MVO [odds ratio (OR) 13.5; 95% confidence interval (CI), 2.15-84.9; P = 0.005 and OR 12.0; 95% CI, 2.94-49.2; P < 0.001, respectively). The presence of HE and relative CT density >2.20 showed a high positive predictive value of 93%, and the absence of these two findings yielded a high negative predictive value of 90% for the predictive value of MVO. Heterogeneous enhancement was significantly associated with LV remodelling (OR 6.75; 95% CI, 1.56-29.29; P = 0.011). CONCLUSION Heterogeneous enhancement detected by MDCT immediately after primary PCI may provide promising information for predicting MVO and LV remodelling in patients with AMI.

Effect of the Mehran risk score for the prediction of clinical outcomes after percutaneous coronary intervention.

BACKGROUND The association of Mehran risk score (MRS) with long-term prognosis in patients treated with percutaneous coronary intervention (PCI) has not been fully reported. We investigated the association between MRS and clinical outcomes in patients who underwent PCI. METHODS Study subjects comprised 2198 patients treated with PCI from the Ibaraki Cardiovascular Assessment Study multicenter registry, excluding patients receiving hemodialysis or who died within 7 days. We categorized them into 4 groups according to MRS (low-risk: ≤5; medium-risk: 6-10; high-risk: 11-16; and very high-risk: ≥16). Contrast-induced acute kidney injury (CI-AKI) was defined as an increase of 0.5mg/dL or 25% in pre-PCI serum creatinine within 1-week post procedure. We evaluated CI-AKI and major adverse cardiac and cerebrovascular events (MACCE), and defined as all-cause death, myocardial infarction, congestive heart failure, or cerebrovascular disorder (stroke or transient ischemic attack). RESULTS A total of 192 (8.7%) patients developed CI-AKI. At multivariate analysis, odds ratio for CI-AKI was 4.09 (95% CI: 1.72-9.17, p=0.002) in the very high-risk group, 1.49 (95% CI: 0.89-2.42, p=0.120) in the high-risk group, and 1.08 (95% CI: 0.74-1.54, p=0.693) in the medium-risk group, as compared with the low-risk group. MACCE in the very high-risk group was more than 5-fold higher [hazard ratio (HR) 5.40, 95% CI: 2.96-9.28, p<0.001] compared with the low-risk group and was also increased in the high-risk (HR 3.72, CI: 2.59-5.32, p<0.001) and medium-risk groups (HR 1.97, CI: 1.45-2.69, p<0.001). Kaplan-Meier analysis showed that increasing risk for MACCE was seen across the groups as MRS increased (p<0.001). CONCLUSION MRS might provide potentially useful information for prediction of CI-AKI and clinical outcomes after PCI.

Drug-eluting versus bare-metal stents in large coronary arteries of patients with ST-segment elevation myocardial infarction: Findings from the ICAS registry

BACKGROUND AND PURPOSE There are a few retrospective subgroup analyses or registries of large-vessel (≥ 3.5mm) stenting. We investigated clinical outcomes of patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DES) and bare-metal stents (BMS) in large coronary vessels. METHODS AND SUBJECTS Of 1100 STEMI patients registered in the Ibaraki Cardiovascular Assessment Study (ICAS) multicenter registry from April 2007 to June 2012 who underwent PCI, we enrolled 454 patients (65.8 ± 12.7 years old, 81% male) with ≥ 3.5-mm stents. We excluded 53 patients with cardiogenic shock or left main trunk lesions. The remaining 401 patients were divided into Group-D, PCI with DES (n = 184), and Group-B, PCI with BMS (n = 217). Propensity score analysis matched 1:1 according to treatment with DES (n = 101) or with BMS (n = 101). We evaluated major adverse cardiac and cerebrovascular events (MACCE) and incidence of stent thrombosis (ST). MACCE was defined as all-cause death, myocardial infarction (MI), target-vessel revascularization (TVR), or cerebrovascular accident (CVA). ESSENTIAL RESULTS During a mean follow-up period of 526 days, all-cause death, MI, CVA, MACCE, and ST were not significantly different in Group-D versus Group-B (all-cause death: 4.35% vs. 4.61%, p = 0.90; MI: 0% vs. 0%; CVA: 2.72% vs. 3.23%, p = 0.76; MACCE: 15.2% vs. 20.3%, p = 0.19; and ST: 0.0% vs. 1.38%, p = 0.11). After adjusting for age, insulin use, multivessel disease, intra-aortic balloon pump use, culprit lesions, and estimated glomerular filtration rate <60 ml/min/1.73 m(2), MACCE was not significantly different between the groups (odds ratio: 0.69; 95% CI: 0.40-1.23; p = 0.21). However, TVR was significantly lower in Group-D than Group-B in Kaplan-Meier analysis (p = 0.048) after propensity score matching. PRINCIPAL CONCLUSION There was no advantage to using a DES in large vessels for preventing a hard endpoint, whereas DES use resulted in a significant reduction in TVR in the patients with STEMI in this registry.

In vivo evaluation of fibrous cap thickness by optical coherence tomography for positive remodeling and low-attenuation plaques assessed by computed tomography angiography

BACKGROUND Coronary plaques with positive remodeling (PR) and low-attenuation plaques (LAP) by computed tomography angiography (CTA) might be associated with plaque vulnerability. The purpose of this study was to assess the relation between coronary plaques with PR and LAP by CTA and fibrous cap thickness measured by optical coherence tomography (OCT). METHODS We used CTA and OCT to assess 102 coronary plaques in patients with coronary artery disease (unstable angina pectoris, n=24; stable angina pectoris, n=78). Plaque characteristics were divided into three groups: 2-feature-positive plaques (PR and LAP; n=32), 1-feature-positive plaques (PR or LAP; n=20), and 2-feature-negative plaques (neither PR nor LAP; n=50). PR was defined as remodeling index (RI) of >1.05 and LAP was defined as CT density value <50HU. RESULTS There were significant differences between the three plaque groups with respect to fibrous cap thickness measured by OCT: 76±24μm in 2-feature-positive plaques, 154±51μm in 1-feature-positive plaques, and 192±49μm in 2-feature-negative plaques (P<0.001). The RI (1.21±0.06, 1.14±0.05, P=0.011) and the presence of thin cap fibroatheroma (TCFA) (<70-μm thickness) (75%, 15%, P=0.001) were significantly higher in UAP than in SAP patients with 2-feature-positive plaques, whereas fibrous cap thickness (68.9±24.1, 92.1±21.9μm, P<0.001) was lower in the UAP patients. In UAP patients, the presence of ring-like enhancement showed higher accuracy of 88% for detection of TCFA. CONCLUSIONS Coronary PR and LAP by CTA were associated with the degree of fibrous cap thickness measured by OCT. CTA can non-invasively provide promising information on plaque vulnerability by identifying coronary plaque with PR and LAP, especially ring-like enhancement.