Tomonori Akasaka

Impact of CYP2C19 polymorphism and proton pump inhibitors on platelet reactivity to clopidogrel and clinical outcomes following stent implantation.

BACKGROUND The response to clopidogrel, and some kind of the drug interaction are multifactorial. METHODS AND RESULTS We enrolled 174 consecutive patients and determined CYP2C19 genotypes, measured platelet aggregation, and assessed the relationship between CYP2C19 genotype and platelet reactivity 24hours after clopidogrel administration, and the risk of cardiovascular events over 18months follow-up. A sub analysis examined the impact of rabeprazole, a proton pump inhibitor (PPI) less affected by CYP2C19. The CYP2C19 genotype was extensive metabolizer (EM) in 36%, intermediate metabolizer (IM) in 45%, and poor metabolizer (PM) in 19%. Platelet reactivity was significantly lower in the EM group than in the IM and PM groups (EM, IM, PM: 3560±1404, 4203±1302, 5084±1007AU•min, P<0.05). The cardiovascular event rate was higher in the IM and PM groups than in the EM group (12.7% and 12.5% vs 1.6%; Hazard ratio for IM 10.6, P=0.029; for PM 11.3, P=0.040). No differences were seen between patients taking (N=50) and not taking (N=124) rabeprazole in residual platelet aggregation (4407±1360 vs 4048±1394, AU•min, P=0.2782), or in cardiovascular events (10.0% vs 8.1%, HR 0.97, P=0.97). CONCLUSIONS CYP2C19 genotype is associated with an increased risk of cardiovascular events following stent implantation in Japanese patients.

Chronic kidney disease status modifies the association of CYP2C19 polymorphism in predicting clinical outcomes following coronary stent implantation

INTRODUCTION There is some controversy regarding the effect of CYP2C19 polymorphism on clinical outcome in patients with dual antiplatelet therapy. Chronic kidney disease (CKD) is associated with increased risk of cardiovascular event, but the association between the possession of CYP2C19 loss-of-function (LOF) alleles and clinical outcome according to the presence of CKD is poorly understood. The aim of this study was to investigate whether CKD status modifies the association of CYP2C19 polymorphism in predicting outcomes in a prospective cohort study. MATERIAL AND METHODS We enrolled 331 patients following coronary stent implantation. Patients were divided into two groups: CKD (n=154) and non-CKD (n=177). Platelet reactivity and CYP2C19 polymorphism were examined. The subjects were further divided into two groups according to the possession of CYP2C19 LOF alleles: carriers and non-carriers. Patients were followed up and clinical events were evaluated according to CKD and carrier status. RESULTS The proportion of high platelet reactivity was significantly higher in carriers than in non-carriers in both CKD (42.4% versus 21.7%; P=0.016) and non-CKD groups (34.3% versus 3.7%; P<0.001). In the non-CKD group alone, the incidence of cardiovascular events was significantly higher in carriers than in non-carriers (13.7% versus 1.7%; P=0.013). Kaplan-Meier analysis demonstrated a significantly higher probability of cardiovascular events in carriers than in non-carriers in the non-CKD group (log-rank test: P=0.013) and there was no significant difference in the CKD group (log-rank test: P=0.591). Multivariate analysis identified carriers as an independent predictor of cardiovascular events only in the non-CKD group alone (hazard ratio: 8.048; 95% confidence interval: 1.066 to 60.757; P=0.043). CONCLUSIONS CYP2C19 polymorphism significantly correlates with clinical outcome in non-CKD patients, and CKD status modifies the association of CYP2C19 polymorphism in predicting clinical outcomes following coronary stent implantation.

Differential Effects of Strong and Regular Statins on the Clinical Outcome of Patients With Chronic Kidney Disease Following Coronary Stent Implantation – The Kumamoto Intervention Conference Study (KICS) Registry –

BACKGROUND The aim of this study was to examine the effects of different statins on the clinical outcomes of Japanese patients with coronary stent implants. METHODS AND RESULTS This study included 5,801 consecutive patients (males, 4,160; age, 69.7±11.1 years, mean±SD) who underwent stent implantation between April 2008 and March 2011. They were treated with a strong statin (n=3,042, 52%, atorvastatin, pitavastatin, or rosuvastatin), a regular statin (n=1,082, 19%, pravastatin, simvastatin, or fluvastatin) or no statin (n=1,677, 29%). The patients with chronic kidney disease (CKD) were divided into mild-to-moderate CKD (30≤eGFR<60, n=1,956) and severe CKD (eGFR <30, n=559). Primary endpoints included cardiovascular death and nonfatal myocardial infarction, including stent thrombosis and ischemic stroke. The clinical outcome for the primary endpoint in mild-to-moderate CKD patients treated with a strong statin (hazard ratio 0.50, 95% confidence interval 0.31-0.81; P=0.005) was significantly lower than in those on no statins, but that in the patients treated with a regular statin was not (P=0.160). The clinical outcome for the primary endpoint in severe CKD patients treated with a strong or regular statin was no different than not being on statin therapy (P=0.446, P=0.194, respectively). CONCLUSIONS In patients with mild-to-moderate CKD, only strong statins were associated with lower risk compared with no statin, but regular statins were not. It is possible that taking a strong statin from the early stage of CKD is useful for suppression of cardiovascular events.

Impact of CYP2C19 polymorphism on clinical outcome following coronary stenting is more important in non-diabetic than diabetic patients☆

OBJECTIVE The aim of this study was to examine the impact of CYP2C19 genotype on clinical outcome in coronary artery disease (CAD) patients with or without diabetes mellitus (DM). METHODS CYP2C19 polymorphism and DM are associated with increased risk of cardiovascular events during antiplatelet therapy following stent implantation. Platelet reactivity during clopidogrel therapy and CYP2C19 polymorphism were measured in 519 CAD patients (males 70%, age 69 years) treated with stent placement. Patients were divided into two groups; DM (n=249), and non-DM (n=270), and clinical events were evaluated according to the carrier state, which included at least one CYP2C19 loss-of-function allele. RESULTS The level of platelet reactivity and incidence of cardiovascular events were significantly different between Carriers and non-Carriers of the non-DM (platelet reactivity: 4501+/-1668 versus 3691+/-1714AU min, P<0.01; events, 32/178 versus 2/92, P<0.01, respectively), however, there was no difference in clinical outcome in the DM group (events, 34/168 versus 14/81, respectively, P=0.57). Multivariate analysis identified CYP2C19 loss-of-function allele carriage as an independent predictor of cardiovascular events in non-DM, but not in DM (non-DM, HR 7.180, 95% CI, 1.701 to 30.298, P=0.007; DM, HR 1.374, 95% CI, 0.394 to 4.792, P=0.618). CONCLUSION The impact of CYP2C19 polymorphism on clinical outcome seems to be more significant in non-DM compared with DM in patients with coronary stents.

High Mortality Rate in Hemodialysis Patients Who Undergo Invasive Cardiovascular Procedures Related to Peripheral Artery Disease – Community-Based Observational Study in Kumamoto Prefecture –

BACKGROUND Cardiovascular disease is a major cause of mortality in hemodialysis patients. The aim was to assess the relationship of various invasive cardiovascular procedures (ICP) to clinical outcome in hemodialysis patients. METHODS AND RESULTS A total of 5,813 patients at 76 facilities were on maintenance hemodialysis in Kumamoto Prefecture. Of these, 4,807 patients at 58 institutions were enrolled. Of 4,807 patients, 212 ICP (4.4%) were performed for various cardiovascular diseases in 189 patients (3.9%). ICP included PCI (n=80), endovascular treatment (n=59), radiofrequency catheter ablation (n=8), implantation of permanent pacemaker (n=15) and ICD (n=5), thoracotomy for valvular diseases (n=16), CABG (n=14), bypass surgery for peripheral artery disease (PAD; n=8), and artificial vessel replacement for aneurysm or aortic dissection (n=7). The overall mortality rate was 10.1% (19/189 patients). The mortality rate was highest in patients who underwent ICP for PAD, compared with other ICP (PAD, 18.2%; non-PAD, 6.7%, P=0.017). Infection and PAD were significant predictors of mortality (infection: OR, 8.30; 95% CI: 1.29-65.13, P=0.027; PAD: OR, 3.76; 95% CI: 1.35-10.48, P=0.012). The presence of inflammation/malnutrition factors was associated with high mortality (OR, 15.49; 95% CI: 3.22-74.12, P=0.0006). CONCLUSIONS In this community-based registry study of 4,807 hemodialysis patients, the mortality rate of PAD patients was high despite ICP.

Comparison of the effect of CYP2C19 polymorphism on clinical outcome between acute coronary syndrome and stable angina

AIM CYP2C19 polymorphism modulates platelet reactivity in coronary artery disease patients with stent implants. However, the impact of the CYP2C19 genotype on clopidogrel response and clinical outcome has not been fully understood to date. METHODS We enrolled 518 consecutive patients with acute coronary syndrome (ACS) (n=214) and stable angina (SA) (n=304). All patients received stent implants followed by dual antiplatelet therapy of aspirin and clopidogrel. We determined CYP2C19 phenotype, measured platelet reactivity, and assessed the risk of cardiovascular events. RESULTS During a median follow-up of 894 days, the rate of cardiovascular events was higher in patients of the ACS group than the SA group (ACS: 20.1%, SA: 12.5%, p=0.015). The mean platelet reactivity was significantly higher in the CYP2C19 loss-of-function allele carriers of the two groups (ACS, non-carriers: 3909±1836AUmin, carriers: 4854±1594AUmin, respectively, p<0.01; SA, 3606±1579AUmin, 4381±1373AUmin, ±SD, p<0.01). In the ACS group, cardiovascular events were higher in the loss-of-function allele carriers (24.6%) versus non-carriers (11.1%, p<0.05), but no such difference was noted in the SA group (carriers: 14.8%; non-carriers: 7.9%, p=0.078). Furthermore, landmark analysis from 30 days did not show differences in ACS group (carriers: 14.8%, non-carriers: 11.1%, p=0.315). Multivariate Cox proportional hazards analysis identified the presence of loss-of-function allele as an independent predictor of cardiovascular events (hazard ratio, 2.1, 95% CI, 1.194-3.587, p=0.010). CONCLUSIONS The impact of CYP2C19 loss-of-function gene on clinical outcome is more powerful in early phase of ACS compared with SA.

Clinical significance of fecal occult blood screening in patients before percutaneous coronary intervention

BACKGROUND The most common reason for premature discontinuation of dual anti-platelet therapy (DAPT) after coronary stenting is the manifestation of gastrointestinal bleeding. Before percutaneous coronary interventions (PCIs), we screened patients who tested positive for fecal occult blood (fecOB). METHODS AND RESULTS On 1789 consecutively admitted cardiac catheterization patients, we performed fecOB examinations; 647 of these patients received PCIs, and 232 of them were fecOB positive. Ultimately, we performed 165 colonoscopies and detected 3 early cancer lesions. CONCLUSIONS Positive results on fecOB screening, before PCI, could indicate lower intestinal lesions. We can perform surgical cancer procedures safely, even with aspirin usage.

Impact of Statin Therapy on Clinical Outcome in Patients With Coronary Spasm

Background Statin therapy reduces the risk of cardiovascular events in patients with obstructive coronary artery disease. The aim of the present study was to determine the effects of statins on the prognosis of patients with coronary vasospastic angina (VSA) free of significant atherosclerotic stenosis. Methods and Results After exclusion of 475 from 1877 consecutive patients who underwent an acetylcholine‐provocation test between January 1991 and December 2010, data of 640 VSA patients without significant organic stenosis of the remaining 1402 were analyzed retrospectively. Propensity score matching was performed to reduce the effect of treatment‐selection bias and possible confounders. The primary endpoint was major adverse cardiac events (MACE), including cardiac death, nonfatal myocardial infarction, and unstable angina. Among the study population, dyslipidemia on admission was identified in 160 of 168 (95.2%) patients of the statin group compared with only 125 of 472 (26.5%) of the no‐statin group. Of the 640 patients, 24 (3.8%) developed MACE. Multivariate Cox hazard regression analysis identified statin therapy as a significant negative predictor of MACE (hazard ratio, 0.11; 95% CI, 0.02–0.84; P=0.033). In the propensity‐score matched cohorts (n=128 each), Kaplan–Meier survival curve showed a better 5‐year MACE‐free survival rate for patients of the statin group compared to the no‐statin group (100% vs 91.7%, respectively; P=0.002). Conclusions Statin therapy correlated with a lower rate of cardiovascular events in VSA patients free of significant organic stenosis. Statins seems to improve the prognosis of VSA patients free of significant organic stenosis.

Patients with both CYP2C19 loss-of-function allele and peripheral endothelial dysfunction are significantly correlated with adverse cardiovascular events following coronary stent implantation

BACKGROUND There is some controversy regarding the effect of CYP2C19 polymorphism on clinical outcome in patients receiving dual antiplatelet therapy (DAPT). Peripheral endothelial dysfunction has recently been reported to predict adverse cardiovascular events. We hypothesized that CYP2C19 loss-of-function (LOF) allele carriers with peripheral endothelial dysfunction had worse prognosis. The aim of this study was to evaluate an additive effect of peripheral endothelial dysfunction on clinical outcome following percutaneous coronary intervention (PCI) in patients with a CYP2C19 variant. METHODS We enrolled 434 patients on DAPT following PCI. CYP2C19 genotype was examined, and we divided patients into two groups: carriers, who had at least one CYP2C19 LOF allele, and non-carriers. Peripheral endothelial dysfunction was examined using reactive hyperemia-peripheral arterial tonometry index (RHI), and we divided patients into low and high RHI. Thus, subjects were divided into four groups, and clinical events were followed up. RESULTS A total of 55 patients had a cardiovascular event. Kaplan-Meier analysis demonstrated a significantly higher probability of cardiovascular events in carriers with low RHI (log-rank test: p=0.007). Multivariate Cox proportional hazards analysis identified both CYP2C19 LOF allele possession (hazard ratio (HR): 1.94; 95% confidence interval (CI): 1.1-3.69; p=0.045) and low RHI (HR: 2.15; 95% CI: 1.22-3.78; p=0.008) as independent and significant predictors of future cardiovascular events. CONCLUSIONS CYP2C19 LOF allele carriers with peripheral endothelial dysfunction were significantly correlated with cardiovascular events. The additional evaluation of peripheral endothelial function along with CYP2C19 polymorphism might improve risk stratification after coronary stent implantation.

Relation between stent thrombosis and calcium channel blocker after drug-eluting stent implantation: Kumamoto Intervention Conference Study (KICS) registry.

BACKGROUND Stent thrombosis (ST) has emerged as a severe complication of percutaneous coronary intervention (PCI). Since the occurrence of ST is lower in Japan than Western countries, there are few data to predict ST after drug-eluting stent (DES) implantation in Japan. We examined the independent predictors of ST incidence after DES implantation in Japanese patients, including the use of calcium channel blockers (CCBs). METHODS AND RESULTS We used data from the Kumamoto Intervention Conference Study registry. There were 6286 consecutive patients enrolled from June 2008 to March 2011. Among them, we analyzed 3493 patients who underwent DES implantation. The incidence of definite/probable ST throughout a median follow-up period of 364 days was 0.57% (20 patients). There were 8 patients with early ST (within 30 days), 8 patients with late ST (between 31 and 365 days), and 4 patients with very late ST (after 1 year). The frequency of CCB use was significantly lower in ST than non-ST patients (25.0% versus 51.4%, respectively, p=0.016). Multiple regression analysis showed that longer stent length (p=0.034), acute coronary syndrome (p=0.039), and the absence of CCB use (p=0.046) were significant and independent predictors of ST within 1 year. CONCLUSIONS These results suggest that CCB use may be associated with a decreased risk of ST after DES implantation within 1 year in Japanese patients.