Comparison of drug-eluting stents in acute myocardial infarction patients with chronic kidney disease.

BACKGROUND/AIMS: To determine which drug-eluting stents are more effective in acute myocardial infarction (MI) patients with chronic kidney disease (CKD). METHODS: This study included a total of 3,566 acute MI survivors with CKD from the Korea Acute Myocardial Infarction Registry who were treated with stenting and followed up for 12 months: 1,845 patients who received sirolimus-eluting stents (SES), 1,356 who received paclitaxel-eluting stents (PES), and 365 who received zotarolimus-eluting stents (ZES). CKD was defined as an estimated glomerular filtration rate < 60 mL/min/1.73 m(2) calculated by the modification of diet in renal disease method. RESULTS: At the 12-month follow-up, patients receiving ZES demonstrated a higher incidence (14.8%) of major adverse cardiac events (MACEs) compared to those receiving SES (10.1%) and PES (12%, p = 0.019). The ZES patients also had a higher incidence (3.9%) of target lesion revascularization (TLR) compared to those receiving SES (1.5%) and PES (2.4%, p = 0.011). After adjusting for confounding factors, ZES was associated with a higher incidence of MACE and TLR than SES (adjusted hazard ratio [HR], 0.623; 95% confidence interval [CI], 0.442 to 0.879; p = 0.007; adjusted HR, 0.350; 95% CI, 0.165 to 0.743; p = 0.006, respectively), and with a higher rate of TLR than PES (adjusted HR, 0.471; 95% CI, 0.223 to 0.997; p = 0.049). CONCLUSIONS: Our findings suggest that ZES is less effective than SES and PES in terms of 12-month TLR, and has a higher incidence of MACE due to a higher TLR rate compared with SES, in acute MI patients with CKD.

Clinical impact of non-high density lipoprotein-cholesterol and apolipoprotein B on clinical outcomes in metabolic syndrome patients with acute myocardial infarction undergoing percutaneous coronary intervention.

BACKGROUND AND OBJECTIVES: Non-high density lipoprotein-cholesterol (non-HDL-C) and apolipoprotein B (ApoB) are markers of atherosclerotic risk and predictors of cardiovascular events. The aim of this study was to evaluate clinical impact of non-HDL-C and ApoB on clinical outcomes in metabolic syndrome (MS) patients with acute myocardial infarction (AMI) undergoing percuatneous coronary intervetion. SUBJECTS AND METHODS: We analyzed 470 MS patients (64.4±12.0 years, 53.6% male) with AMI who were followed-up for 12-month after percutaneous coronary intervention (PCI) from December 2005 to January 2008 in a single center. These patients were divided into 2 groups based on median values of non-HDL-C and ApoB. We studied their baseline and follow-up relation with 12-month clinical outcomes, all-cause death and major adverse cardiac events (MACE). RESULTS: Mean values of baseline non-HDL-C and ApoB were 141.2±43.1 mg/dL and 99.3±29.0 mg/dL respectively. During 12-month follow-up 32 MACE (6.8%) and 12 deaths (2.5%) occurred. We observed significant correlation between non-HDL-C and ApoB. Twelve-month MACE and all-cause death after PCI showed no significant relation as non-HDL-C or ApoB levels increased. Follow-up patients (n=306, rate 65%) also did not show significant relation with clinical outcomes. Twelve-month MACE decreased as non-HDL-C and ApoB reduction rates increased. CONCLUSION: There was no significant association between higher non-HDL-C or ApoB and 12-month clinical outcomes in MS patients with AMI undergoing PCI. ApoB was found to be a better predictor of 12-month MACE than non-HDL-C based on their reduction rates.

Clinical impact of thrombus aspiration during primary percutaneous coronary intervention: results from Korea Acute Myocardial Infarction Registry.

BACKGROUND: The role of thrombus aspiration (TA) as an adjunct to primary percutaneous coronary intervention (PPCI) remains a matter of controversy. METHODS AND RESULTS: A total of 2105 patients enrolled in the nationwide prospective Korea Acute Myocardial Infarction Registry, a cohort of 745 (35.4%) patients who underwent TA during PPCI was compared with 1360 (64.6%) patients who underwent conventional PCI without TA. Clinical outcomes at 12-months of overall enrolled patients and subgroups according to key variables were assessed using Cox regression models adjusted by propensity score. Although there was no significant difference among overall patients, in subgroup analyses, administration of glycoprotein (GP) IIb/IIIa inhibitor during PPCI [adjusted hazard ratio (HR) 0.329, 95% confidence interval (CI) 0.126-0.860, p=0.023] and left anterior descending (LAD) as a culprit lesion (adjusted HR 0.516, 95% CI 0.275-0.971, p=0.040) were the settings, in which TA was associated with a lower major adverse cardiac events (MACE) rate compared with non-TA. CONCLUSIONS: Although TA does not improve clinical outcomes in overall patients who underwent PPCI, TA for LAD occlusion improves 12-month MACE. Furthermore, use of GP IIb/IIIa inhibitor with TA has a synergistic effect on clinical outcomes.

Drug-eluting stent as an option for intractable in-stent coronary restenosis.

A 51-year-old man was admitted due to an acute anterior ST-segment elevation myocardial infarction. After thrombolytic therapy using recombinant tissue plasminogen activator, stent implantation was performed from the proximal left anterior descending artery (LAD) to the mid LAD using a bare-metal stent (BMS). Since then, the patient suffered five repeated episodes of in-stent restenosis (ISR). At the first ISR, he was treated with plain old balloon angioplasty (POBA). At the second ISR, he was treated with brachytherapy, and at the third ISR, he was treated with POBA and one more BMS distal to the previously implanted stent. At the forth, only POBA was performed, and finally, at the fifth ISR, a sirolimus-eluting stent was implanted. Following that, the patient remained asymptomatic and follow-up coronary angiography showed no ISR.

Role of intravascular ultrasound in patients with acute myocardial infarction undergoing percutaneous coronary intervention.

Stent thrombosis and restenosis remain drawbacks of drug-eluting stents in patients with acute myocardial infarction (AMI). Intravascular ultrasound (IVUS) guidance for stent deployment helps optimize its results in stable patients. The aim of this study was to examine the utility of routine IVUS guidance in patients with AMI undergoing percutaneous coronary intervention (PCI). Employing data from Korea Acute Myocardial Infarction Registry (KAMIR), we analyzed 14,329 patients with AMI from April 2006 through September 2010. Patients with cardiogenic shock and rescue PCI after thrombolysis were excluded. Clinical outcomes of 2,127 patients who underwent IVUS-guided PCI were compared to those of 8,235 patients who did not. Mean age was 63.6 ± 13.5 years and 72.3% were men. Patients undergoing IVUS-guided PCI were younger, more often men, more hyperlipemic, and had increased body mass index and left ventricular ejection fraction. Number of treated vessels and stents used, stent length, and stent diameter were increased in the IVUS-guided group. Multivessel involvement was less frequent and American College of Cardiology/American Heart Association type C lesion was more frequent in the IVUS-guided group. Drug-eluting stents were more frequently used compared to bare-metal stents in the IVUS group. There was no significant relation of stent thrombosis between the 2 groups. Twelve-month all-cause death was lower in the IVUS group. After multivariate analysis and propensity score adjustment, IVUS guidance was not an independent predictor for 12-month all-cause death (hazard ratio 0.212, 0.026 to 1.73, p = 0.148). In conclusion, this study does not support routine use of IVUS guidance for stent deployment in patients who present with AMI and undergo PCI.

The protective mechanism of antioxidants in cadmium-induced ototoxicity in vitro and in vivo.

BACKGROUND: Several heavy metals have been shown to have toxic effects on the peripheral and central auditory system. Cadmium (Cd2+) is an environmental contaminant showing a variety of adverse effects. Given the current rate of release into the environment, the amount of Cd2+ present in the human body and the incidence of Cd2+-related diseases are expected to increase. OBJECTIVE: The overall aim of this study was to gain further insights into the mechanism of Cd2+-induced ototoxicity. METHODS: Cell viability, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), cytochrome c (cyt c), phosphorylated extracellular signal-regulated protein kinase (p-ERK), caspases, morphologic change, and functional changes in HEI-OC1 cells, rat cochlear explants, and mouse cochlea after Cd2+ exposure were measured by flow cytometry, immunohistochemical staining, Western blot analysis, and auditory brainstem response (ABR) recording. Mechanisms underlying Cd2+ototoxicity were studied using inhibitors of different signaling pathways, caspases, and antioxidants. RESULTS: Cd2+ exposure caused cell death, ROS generation, MMP loss, cyt c release, activation of caspases, ERK activation, apoptosis, and finally auditory threshold shift. Cd2+ toxicity interfered with inhibitors of cellular signaling pathways, such as ERK and c-jun N-terminal kinase, and with caspase inhibitors, especially inhibitors of caspase-9 and caspase-3. The antioxidants N-acetyl-l-cysteine and ebselen showed a significant protective effect on the Cd2+ toxicity. CONCLUSIONS: Cd2+ is ototoxic with a complex underlying mechanism. However, ROS generation may be the cause of the toxicity, and application of antioxidants can prevent the toxic effect.