Sang Sig Cheong

Duration of dual antiplatelet therapy after implantation of drug-eluting stents.

BACKGROUND The potential benefits and risks of the use of dual antiplatelet therapy beyond a 12-month period in patients receiving drug-eluting stents have not been clearly established. METHODS In two trials, we randomly assigned a total of 2701 patients who had received drug-eluting stents and had been free of major adverse cardiac or cerebrovascular events and major bleeding for a period of at least 12 months to receive clopidogrel plus aspirin or aspirin alone. The primary end point was a composite of myocardial infarction or death from cardiac causes. Data from the two trials were merged for analysis. RESULTS The median duration of follow-up was 19.2 months. The cumulative risk of the primary outcome at 2 years was 1.8% with dual antiplatelet therapy, as compared with 1.2% with aspirin monotherapy (hazard ratio, 1.65; 95% confidence interval [CI], 0.80 to 3.36; P=0.17). The individual risks of myocardial infarction, stroke, stent thrombosis, need for repeat revascularization, major bleeding, and death from any cause did not differ significantly between the two groups. However, in the dual-therapy group as compared with the aspirin-alone group, there was a nonsignificant increase in the composite risk of myocardial infarction, stroke, or death from any cause (hazard ratio, 1.73; 95% CI, 0.99 to 3.00; P=0.051) and in the composite risk of myocardial infarction, stroke, or death from cardiac causes (hazard ratio, 1.84; 95% CI, 0.99 to 3.45; P=0.06). CONCLUSIONS The use of dual antiplatelet therapy for a period longer than 12 months in patients who had received drug-eluting stents was not significantly more effective than aspirin monotherapy in reducing the rate of myocardial infarction or death from cardiac causes. These findings should be confirmed or refuted through larger, randomized clinical trials with longer-term follow-up. (ClinicalTrials.gov numbers, NCT00484926 and NCT00590174.)

Optimal Duration of Dual Antiplatelet Therapy after Drug-Eluting Stent Implantation: A Randomized Controlled Trial

Background— The risks and benefits of long-term dual antiplatelet therapy remain unclear. Methods and Results— This prospective, multicenter, open-label, randomized comparison trial was conducted in 24 clinical centers in Korea. In total, 5045 patients who received drug-eluting stents and were free of major adverse cardiovascular events and major bleeding for at least 12 months after stent placement were enrolled between July 2007 and July 2011. Patients were randomized to receive aspirin alone (n=2514) or clopidogrel plus aspirin (n=2531). The primary end point was a composite of death resulting from cardiac causes, myocardial infarction, or stroke 24 months after randomization. At 24 months, the primary end point occurred in 57 aspirin-alone group patients (2.4%) and 61 dual-therapy group patients (2.6%; hazard ratio, 0.94; 95% confidence interval, 0.66–1.35; P=0.75). The 2 groups did not differ significantly in terms of the individual risks of death resulting from any cause, myocardial infarction, stent thrombosis, or stroke. Major bleeding occurred in 24 (1.1%) and 34 (1.4%) of the aspirin-alone group and dual-therapy group patients, respectively (hazard ratio, 0.71; 95% confidence interval, 0.42–1.20; P=0.20). Conclusions— Among patients who were on 12-month dual antiplatelet therapy without complications, an additional 24 months of dual antiplatelet therapy versus aspirin alone did not reduce the risk of the composite end point of death from cardiac causes, myocardial infarction, or stroke. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT01186146.

Comparison of Zotarolimus-Eluting Stents With Sirolimus- and Paclitaxel-Eluting Stents for Coronary Revascularization The ZEST (Comparison of the Efficacy and Safety of Zotarolimus-Eluting Stent with Sirolimus-Eluting and PacliTaxel-Eluting Stent for Coronary Lesions) Randomized Trial

OBJECTIVES The aim of this study was to evaluate the relative efficacy and safety of zotarolimus-eluting stents (ZES) in comparison with the established and widely used sirolimus- (SES) and paclitaxel-eluting stents (PES) in routine clinical practice. BACKGROUND Whether ZES might provide similar clinical and angiographic outcomes in a broad spectrum of patients compared with SES or PES is undetermined. METHODS We performed a single-blind, multicenter, prospectively randomized trial to compare ZES with SES and PES in 2,645 patients undergoing percutaneous coronary intervention. The primary end point was a composite of major adverse cardiac events (MACE) (death, myocardial infarction, and ischemia-driven target vessel revascularization) at 12 months. A noninferiority comparison (ZES vs. SES) and a superiority comparison (ZES vs. PES) were performed for the primary end point. RESULTS Baseline clinical and angiographic characteristics were similar in the 3 groups. At 12 months, the ZES group showed noninferior rates of MACE compared with the SES group (10.2% vs. 8.3%, p for noninferiority = 0.01, p for superiority = 0.17) and significantly fewer MACE than the PES group (10.2% vs. 14.1%, p for superiority = 0.01). The incidence of death or myocardial infarction was similar among the groups (ZES vs. SES vs. PES, 5.8% vs. 6.9% vs. 7.6%, respectively, p = 0.31). The incidence of stent thrombosis was significantly lower in the SES group (ZES vs. SES vs. PES, 0.7% vs. 0% vs. 0.8%, respectively, p = 0.02). CONCLUSIONS In this large-scale, practical randomized trial, the use of ZES resulted in similar rates of MACE compared with SES and in fewer MACE compared with PES at 12 months. (Comparison of the Efficacy and the Safety of Zotarolimus-Eluting Stent Versus Sirolimus-Eluting Stent and PacliTaxel-Eluting Stent for Coronary Lesions; NCT00418067).

Comparison of the Efficacy and Safety of Zotarolimus-, Sirolimus-, and Paclitaxel-Eluting Stents in Patients With ST-Elevation Myocardial Infarction

Drug-eluting stents (DESs) are increasingly used for treatment of acute ST-segment elevation myocardial infarction (STEMI), but there are few comparisons of outcomes of various types of DES. We compared the efficacy and safety of zotarolimus-eluting stents (ZESs), sirolimus-eluting stents (SESs), and paclitaxel-eluting stents (PESs) in primary intervention for STEMI. This multicenter, prospectively randomized ZEST-AMI trial included 328 patients at 12 medical centers who were randomly assigned to ZES (n = 108), SES (n = 110), or PES (n = 110) deployment. The primary end point was major adverse cardiac events (death, MI, and ischemia-driven target vessel revascularization) at 12 months. Secondary end points included the individual components of the primary end point, late loss, angiographic restenosis, and stent thrombosis. Baseline clinical and angiographic characteristics were well matched. In-segment late loss (0.28 +/- 0.42 vs 0.46 +/- 0.48 vs 0.47 +/- 0.50 mm, respectively, p = 0.029) and restenosis rate (2.7% vs 15.9% vs 12.3%, respectively, p = 0.027) at 8 months were lowest in the SES group compared to the ZES and PES groups. At 12 months, cumulative incidence rates of primary end points in the ZES, SES, and PES groups were 11.3%, 8.2%, and 8.2%, respectively (p = 0.834). There were 2 acute (in the SES group) and 5 subacute (2 in the SES group and 3 in the PES group) stent thromboses. Incidence of death, recurrent MI, or ischemia-driven target vessel revascularization did not differ among the 3 groups. In conclusion, despite the difference in restenosis rate, the efficacy and safety of the 3 different DESs showed similar, acceptable results in the treatment of STEMI.

Ergonovine echocardiography as a screening test for diagnosis of vasospastic angina before coronary angiography

OBJECTIVES In patients with chest pain suggestive of variant angina, we performed this prospective study to test the specificity and diagnostic validity of ergonovine echocardiography (detection of regional wall motion abnormality during bedside ergonovine challenge) as a screening procedure before coronary angiography. BACKGROUND Spasm provocation test outside the catheterization room has generally not been accepted as a safe diagnostic method. METHODS Ergonovine echocardiography was performed in 80 consecutive patients with chest pain syndrome after confirmation of negative treadmill or normal stress myocardial perfusion scan results using thallium-201. A bolus of ergonovine maleate was injected at 5-min intervals up to a total cumulative dosage of 0.35 mg with echocardiographic monitoring of left ventricular wall motion. A 12-lead electrocardiogram (ECG) was also recorded every 3 min after each ergonovine injection. Positive test results were development of regional wall motion abnormalities or transient ST segment elevation or depression >0.1 mV in any single lead of the 12-lead ECG. Coronary angiography was undertaken within 2 +/- 4 days (mean +/- SD) after ergonovine echocardiography, and the spasm provocation test with acetylcholine or ergonovine was performed in patients with normal angiographic findings or lumen diameter narrowing <70%. RESULTS On the basis of angiographic criteria, 56 patients had coronary vasospasm; this finding was later ruled out in 19 patients with near-normal angiographic results by a negative response on the spasm provocation test. In the remaining five patients, coronary spasm provocation was not performed because they revealed a high degree of fixed stenosis (lumen diameter narrowing 97 +/- 4%). Ergonovine echocardiography could diagnose coronary vasospasm before angiography, with a sensitivity of 91% (51 of 56 patients, 95% confidence interval [CI] 84% TO 98%) and specificity of 88% (21 of 24 patients, 95% CI 75% to 100%). Of 53 patients showing regional wall motion abnormalities during ergonovine echocardiography, characteristic ST segment elevation in the simultaneously recorded ECG was observed in only 20 (38%). There were no complications, including myocardial infarction or fatal arrhythmia, during the test. CONCLUSIONS Ergonovine echocardiography before coronary angiography is safe and can be used as a reliable diagnostic screening test for coronary vasospasm in patients with negative treadmill or normal stress myocardial perfusion scan results. These findings suggest that invasive coronary angiography can be avoided in selected patients for the diagnosis of vasospastic angina.

Factors determining the exercise capacity in mitral stenosis

In mitral stenosis, peak pulmonary pressure after exercise rather than valve area at rest or mitral gradient, was found to be an important factor in determining the exercise capacity.

Prognostic Influence of Diabetes Mellitus on Long-Term Clinical Outcomes and Stent Thrombosis After Drug-Eluting Stent Implantation in Asian Patients

Diabetes mellitus has been associated with an increased risk of mortality and stent thrombosis after implantation of drug-eluting stents (DES). Little is known about the prognostic impact of diabetes on clinical outcomes in an Asian population treated with DES. We compared adverse outcomes between 865 patients with diabetes and 2,295 patients without diabetes treated with DES after adjustment for differences in baseline risk factors in the patients. The primary outcome was the composite of death, nonfatal myocardial infarction, or target-vessel revascularization (TVR). The 3-year unadjusted rates of death (5.8% vs 3.5%, p = 0.002) and TVR (12.2% vs 8.6%, p = 0.003) were significantly higher in patients with diabetes. After adjustment for baseline differences, the risk of TVR remained higher in patients with diabetes (hazard ratio 1.37, 95% confidence interval [CI] 1.04 to 1.81, p = 0.03), but the risk of death did not (hazard ratio 1.35, 95% CI 0.89 to 2.05, p = 0.16). The 3-year adjusted risk of the primary composite outcome was significantly higher in patients with diabetes compared with patients without diabetes (23.3% vs 16.1%, hazard ratio 1.24, 95% CI 1.02 to 1.51, p = 0.03). Insulin use was an independent predictor for each outcome (death, TVR, and composite outcome). After adjustment by baseline risk profile and for propensity, diabetes was not associated with an increased risk of stent thrombosis (multivariable-adjusted hazard ratio 0.87, 95% CI 0.36 to 2.15, p = 0.77 and propensity-adjusted hazard ratio 0.87, 95% CI 0.37 to 2.06, p = 0.76). In conclusion, diabetic status was associated with increased TVR without a significantly increased rate of death. A diabetes-associated excess risk of stent thrombosis was not observed in Asian patients.

Impact of Female Gender on Bleeding Complications After Transradial Coronary Intervention (from the Korean Transradial Coronary Intervention Registry)

Besides poor clinical outcomes, female gender has been known as a high-risk factor for bleeding complications. This study aimed to investigate the impact of gender on clinical outcomes and bleeding complications after transradial coronary intervention (TRI). The Korean TRI registry is a retrospective multicenter registry with 4,890 patients who underwent percutaneous coronary intervention in 2009 at 12 centers. To compare clinical outcomes and bleeding complications between the male and female groups, we performed a propensity score matching in patients who received TRI. A total of 1,194 patients (597 in each group) were studied. The primary outcome was 1-year major adverse cardiac events, including all-cause mortality, myocardial infarction, target vessel revascularization, and stroke. The secondary outcome was major bleeding (composite of bleeding requiring transfusion of ≥2 units of packed cells or bleeding that was fatal). The proportion of major adverse cardiac events was similar between the 2 groups (6.2% vs 4.7%, p = 0.308). The female group had a greater incidence of major bleeding (0.3% vs 3.2%, p <0.001). On multivariate analysis, female gender (odds ratio [OR] 7.748, 95% confidence interval [CI] 1.767 to 13.399), age ≥75 years (OR 5.824, 95% CI 2.085 to 16.274), and chronic kidney disease (OR 7.264, 95% CI 2.369 to 12.276) were independent predictors of major bleeding. In conclusion, the female gender had a tendency for more bleeding complications than male gender after TRI without difference in the clinical outcome.

Current Practice of Transradial Coronary Angiography and Intervention: Results from the Korean Transradial Intervention Prospective Registry

Background and Objectives Although increasing evidence has indicated that radial access is a beneficial technique, few studies have focused on Korean subjects. The aim of this study was to evaluate current practice of coronary angiography (CAG) and percutaneous coronary intervention (PCI) using radial access in South Korea. Subjects and Methods A total of 6338 subjects were analyzed from Korean Transradial Intervention prospective registry that was conducted at 20 centers in Korea. After evaluating the initial access, subjects intended for radial access were assessed for their baseline, procedure-related, and complication data. Subjects were categorized into three groups: group of overall subjects (n=5554); group of subjects who underwent PCI (n=1780); and group of subjects who underwent primary percutaneous coronary intervention (PPCI) (n=167). Results The rate of radial artery as an initial access and the rate of access site crossover was 87.6% and 4.4%, respectively, in overall subjects. Those rates were 82.4% and 8.1%, respectively, in subjects who underwent PCI, and 60.1% and 4.8%, respectively, in subjects who underwent PPCI. For subjects who underwent CAG, a 6-F introducer sheath and a 5-F angiographic catheter was the most commonly used. During PCI, a 6-F introducer sheath (90.6%) and a 6-F guiding catheter were standardly used. Conclusion The large prospective registry allowed us to present the current practice of CAG and PCI using radial access. These data provides evidence to achieve consensus on radial access in CAG and PCI in the Korean population.

Response to Letter Regarding Article, “Optimal Duration of Dual Antiplatelet Therapy After Drug-Eluting Stent Implantation: A Randomized, Controlled Trial”

We thank Dr Sardar and colleagues for their interest in our recent article1 and appreciate the opportunity to reply. We agree that medication adherence is associated with clinical outcomes and remains an important issue in clinical drug trials. Unfortunately, there are no definite methods for assessing adherence to medications. In our study, pill count was used to determine medication adherence, and pharmacy data were electronically checked by medical insurance system. Medical adherence in this type of study is considered generally poor. Even in the Platelet Inhibition and Patient Outcome (PLATO) trial, medical adherence was ≈80%.2 In this context, we believe that medical adherence in our study seems to be acceptable. Time from index procedure to randomization was rather variable, but most patients were enrolled between 12 …