[show abstract][hide abstract] ABSTRACT: BACKGROUND: Patients with reduced responsiveness to clopidogrel often have diminished platelet inhibition, a factor associated with increased rates of major adverse cardiovascular events. Clinical trials that have focused on reducing high on-treatment platelet reactivity (HPR) with an additional loading dose of clopidogrel have reported varying effects. Prasugrel, a newer thienopyridine, exhibits a more consistent antiplatelet effect and more rapid onset time when compared to clopidogrel. We hypothesize that prasugrel reloading would be more effective than clopidogrel reloading in patients with HPR after an initial loading dose of clopidogrel.Method/Design: Comparison of Prasugrel and Clopidogrel Reloading on High Platelet Reactivity in Clopidogrel-loaded Patients Undergoing Percutaneous Coronary Intervention (PRAISE-HPR) is a prospective, randomized, open-label, active controlled study. A total of 76 patients undergoing percutaneous coronary intervention (PCI), with HPR after administration of a loading dose of clopidogrel will be randomly assigned to either prasugrel or clopidogrel groups, and patients in each group will be reloaded with 20 mg of prasugrel or 300 mg of clopidogrel. The primary endpoint will be HPR at 24 hours after PCI, as determined by the VerifyNow assay during the study period. The rate of sustained high platelet reactivity and 30-day clinical outcomes will also be measured. DISCUSSION: PRAISE-HPR is a randomized controlled clinical trial to investigate the efficacy and safety of reloading prasugrel and clopidogrel in suppressing residual high platelet reactivity. The results will be made publicly available in the year 2013.Trial registration: NCT01609647.
[show abstract][hide abstract] ABSTRACT: The aim of this study was to confirm the predictive cut-off values for P2Y12 reaction units (PRU) and aspirin reaction units (ARU) and to evaluate the clinical impact of VerifyNow® assays.
From November 2007 to October 2009, 186 eligible patients were prospectively recruited. Post-treatment platelet reactivity was measured by VerifyNow® assays within 12 to 24 hours after intervention, followed by standard dual maintenance dose therapy for 1 year. All patients had scheduled clinical follow-ups at 1, 3, 6, and 12 months.
The rate of low responders to clopidogrel, aspirin, and both drugs were 41.4%, 10.2%, and 3.8%, respectively. The predictive factors for low responsiveness to clopidogrel (PRU ≥240) were female sex, age, and non-use of cilostazol medication in our univariate analysis and age ≥65 years and non-use cilostazol in the multivariate analysis. The predictors of low responsiveness to aspirin (ARU ≥550) were male sex and age in both univariate and multivariate analyses. There was no significant difference in the clinical event rate with a cut-off value of PRU ≥240 or ARU ≥550 for 30 days and 1-year (p>0.05).
Hyporesponsiveness to antiplatelet agents (namely aspirin and clopidogrel) was identified in about half of the patients. The cut-off point of PRU ≥240 or ARU ≥550 did not confer predictive value for 30-day or 1-year clinical event rates in patients who had undergone coronary intervention with drug-eluting stents.
[show abstract][hide abstract] ABSTRACT: The aim of this study was to determine whether the adoption of new performance processes reduced the door-to-balloon time for primary percutaneous coronary intervention (PCI). To reduce the door-to-balloon time, we adopted 3 new performance processes: concurrent activation at the emergency department rather than stepwise activation; direct phone call rather than using a pager or message; patient transferred to catheterization laboratory before the PCI team arrive. A total of 139 consecutive patients were compared before and after the new performance processes. After the adoption of the new processes, median door-to-balloon time reduced significantly from 133 to 76 minutes (P < .0001) and patients undergoing primary PCI within 90 minutes increased significantly from 16% to 72% (P < .0001). Among the subdivisions of the door-to-balloon time, door-to-consent time and door-to-laboratory arrival time decreased significantly (50.0 vs 20.5 minutes, P < .0001; 95.0 vs 40.0 minutes, P < .0001, respectively).
[show abstract][hide abstract] ABSTRACT: The plasma concentration of N-terminal pro-brain natriuretic peptide (NT-pro-BNP) is a st-rong prognostic indicator for patients with heart failure (HF) across all stages of the condition. Several clinical trials have de-monstrated convincingly that neurohormonal modulation on the renin angiotensin system (RAS) decreases plasma NT-pro-BNP level and results in favorable outcomes. But there are still limited comparative data on the neuro-hormonal modulatory effects of two RAS inhibitors: angiotensin converting enzyme inhibitor and angiotensin receptor blocker.
This study was a prospective, multi-center, randomized, open-label, controlled, and non-inferiority study involving 445 patients with left ventricular ejection fraction (LVEF) less than 45%. Patients were assigned to receive either valsartan (target dose of 160 mg bid) or enalapril (target dose of 10 mg bid) for 12 months. We compared plasma NT-pro-BNP, high sensitive C-reactive protein (hs-CRP) level and echocardiographic parameters before and after treatment with valsartan or enalapril.
The NT-pro-BNP and hs-CRP levels were significantly decreased after 12 months of treatment with valsartan and enalapril. The percentage change was similar between both groups. LVEF improved and left ventricular internal dimensions were decreased in both groups, and there were no significant differences between two groups.
Valsartan is as effective on improving plasma NT-pro-BNP level as enalapril in patients with stable chronic HF.
[show abstract][hide abstract] ABSTRACT: We present an unusual pattern of single coronary artery which has not been reported previously. The proximal portion of the left anterior descending (LAD) artery gives rise to right coronary artery (RCA) and the distal LAD extends to the posterior descending artery which reaches the cardiac crux. A stent was implanted successfully at the middle portion of the LAD just beyond the origin of the RCA.
[show abstract][hide abstract] ABSTRACT: Cardiovascular manifestations in hyperthyroidism occur frequently with various phenotypes. An association between hyperthyroidism and pulmonary arterial hypertension has been reported. In previously reported cases, the hemodynamic and symptomatic recovery of pulmonary arterial hypertension is usually concomitant with achievement of euthyroidism. We report a patient who had pulmonary arterial hypertension associated with Graves' disease, which persisted after euthyroidism was obtained.
[show abstract][hide abstract] ABSTRACT: We report a case of a 19-year-old female with an elevated plasma B-type natriuretic peptide (BNP) level, but without evidence of heart failure (HF). She presented with non-specific chest pain and a high level of the B-type natriuretic peptide, despite having unremarkable findings on physical examination, laboratory analysis, electrocardiogram, echocardiogram, chest X-ray, chest computed tomography, whole body scan, and coronary angiography. We attribute this finding to a genetic variation in the synthesis and cleavage of the natriuretic peptides.
[show abstract][hide abstract] ABSTRACT: Left transradial coronary angiography may result in damage of both radial arteries in patients who experienced right radial access. In some patients, the left radial artery has been used as a graft. We investigated whether graft angiography using right radial access is feasible in patients with bypass surgery to preserve the left radial artery as a future graft.
A total of 109 consecutive patients with bypass surgery who had undergone right radial access underwent graft angiography via the same access.
Sixteen (15%) patients were excluded because of the presence of a severely tortuous right subclavian artery. Bypass graft angiography via right radial or brachial access was completed successfully in 90 (97%) out of 93 patients. In 3 (3%) of patients, femoral access was needed to complete the angiography. Saphenous vein grafts were cannulated selectively in 150 (90%) of 167 grafts with satisfactory image quality and not found even on the aortogram in the other 17 (10%) grafts. Ninety-two (89%) out of 103 left mammary grafts were cannulated selectively or semi-selectively using a modified Simmons catheter, resulting in satisfactory image quality. The other 11 (11%) grafts were visualized non-selectively using a Judkins Left catheter, and resulting in acceptable image quality in 10 (91%) grafts. There were no procedure-related complications.
Graft angiography via right radial access can be performed reliably in most patients that lack severe subclavian tortuosity.
[show abstract][hide abstract] ABSTRACT: Retrograde wire approach has been emerged as a useful tool to enhance success rate in coronary chronic total occlusion (CTO) intervention. Therefore, we tried to report the initial experience of retrograde approach and its clinical implication on CTO intervention.
From February 2007 to July 2008, retrograde approaches were performed in 28 patients with 31 CTO lesions out of 61patients. A hydrophilic coated guidewire was inserted by using microcatheter or over-the-wire (OTW) balloon through the collateral channel (septal or epicardial artery) via several strategies.
Mean age of patients was 63.4+/-11.6 years. Male and female were 20 and 8 patients, respectively. The target artery with CTO lesions included the right coronary artery (45.2%), the left anterior descending artery (51.6%), and the left circumflex artery (3.2%). The mean length of CTO lesion was 18.4+/-16.4 mm. Overall technical success rate was 64.5%. The success rate of primary attempt was 78.9%, while the success rate of immediate and secondary attempt was 41.7%. Collateral channel dissections were observed in 3 patients and no patients among these patients developed cardiac tamponade. One patient had a silent non-Q wave myocardial infarction (MI) after the procedure. One failed patient died suddenly 3 days after the procedure. After percutaneous coronary intervention (PCI) procedure, no case was performed target vessel revascularization (TVR), urgent coronary artery bypass graft (CABG), and urgent PCI.
Retrograde approach is an evolving technique to improve the success rate of CTO intervention. After the learning curve period, this technique could be the useful tool to enhance success rate in CTO intervention.
[show abstract][hide abstract] ABSTRACT: Background and Objectives: Cilostazol, a selective inhibitor of phosphodiesterase III (PDE III), prevents inacti- vation of the intracellular second messenger cyclic adenosine monophosphate (cAMP) and irreversibly inhibits platelet aggregation and vasodilation. Hence, we performed this prospective randomized study to evaluate the clinical effects of additional cilostazol administration in patients receiving dual antiplatelet therapy after drug- eluting stent (DES) insertion. Subjects and Methods: Between December 2003 and June 2006, we enrolled a total 603 consecutive patients who underwent successful percutaneous coronary intervention (PCI) with DES in- sertion at Dong-A University Hospital. Study patients received dual antiplatelet therapy (aspirin and clopidogrel, n=301) for at least six months or dual antiplatelet therapy (six months) combined with cilostazol medication for one month (triple therapy, n=302) after PCI. We investigated the incidence of major adverse cardiac events (MACE) at one month and six months after the initiation of medical therapy. MACE was defined as a composite of death, myocardial infarction (MI), stent thrombosis, and target lesion revascularization (TLR). Platelet function was evaluated in 66 patients (dual therapy group, n=40; triple therapy group, n=26) using a Chrono-Log platelet aggregometer and the VerifyNow P2Y12 assay system. Results: The MACE rate was 0.66% in the triple therapy group (death only, 0.67%) and 1.67% in the dual therapy group (death, 0.67%; MI, 0.67%; stent thrombosis, 0.99%; TLR, 0.99%) at one month after PCI (p=0.087). At six months, there were no differences in the MACE rate between the two groups (triple group vs. dual group=2.65% vs. 3.99%, p=0.864). In laboratory tests, platelet aggregation induced by agonists of ADP (27.92±13.04% vs. 40.9±15.78%, p=0.0008), collagen (13.73±6.95% vs. 27.43±14.87%, p=0.03), and epinephrine (10.38±7.82% vs. 15.5±10.45%, p=0.0000) were lower in the triple therapy group versus the dual therapy group. However, platelet aggregation induced by agonists of ara- chidonic acid (3.23±1.07% vs. 3.78±2.12%, p=0.23) and ristocetin (29.19±35.55% vs. 44.78±32.65%, p= 0.07) and aspirin reaction unit (412.96±96.25 vs. 427.93±76.24, p=0.48) measured by VerifyNow were not different in the triple group versus the dual group. Conclusion: Additional administration of cilostazol did not decrease the MACE rate when compared to dual therapy six months after PCI in patients with DES. (Korean Circ J 2009;39:21-25)
[show abstract][hide abstract] ABSTRACT: We investigated the effect of adipose tissue-derived stromal cells (ADSC) therapy on cardiac contractility and remodeling in the C57BL/6 mouse model of acute myocardial infarction (AMI).
30 adult male C57BL/6 mice were randomized into 2 groups, namely, AMI+media (control, n=15) and AMI+ADSC (n=15). AMI was produced by left anterior descending coronary artery ligation. After AMI induction, 1 x 10(6) ADSC or media were intramyocardially injected and the results compared. Echocardiographic and histological analyses of surviving mice (n=20) were conducted. Echocardiography was performed before cell implantation and 2 weeks after transplantation.
LVEF and FS improved in the ADSC group compared to the control (P<0.01). LVEDD in the ADSC group decreased slightly from 4.65+/-0.63 mm to 4.14+/-0.53 mm compared to the control, but there was no statistical difference (P=0.072). LVESD decreased significantly in the ADSC group (P<0.05). A significant difference in scar formation and infarct size was observed between the ADSC and control group 2 weeks after AMI (P<0.05). ADSC were observed to migrate into injured sites and integrate into scar areas and increased vascular density in the infarct site compared to control group (P<0.05). Additionally, some transplanted ADSC expressed the endothelial marker.
Echocardiography and histological analysis revealed that improvement in cardiac function and ventricular remodeling was better in the ADSC group than in the control. This suggests that ADSC is a good candidate for cell therapy in cardiovascular disease.
International journal of cardiology 12/2008; 139(2):166-72. · 7.08 Impact Factor
[show abstract][hide abstract] ABSTRACT: Background and Objectives:Cardiac troponin I (cTnI) is a sensitive and specific marker of myocardial injury. Although myocardial infarction due to coronary artery occlusion is the most common cause of cTnI elevation, its rise has been reported in non-coronary artery diseases such as paroxysmal tachycardia. This study was conducted to determine the incidence of cTnI elevation in supraventricular tachycardia and to identify the factors associated with the rise in cTnI. Subjects and Methods:We studied sixty-nine patients (35 males and 34 females, average age: 59±14 years) who were admitted for supraventricular tachycardia without evidence of coronary artery disease between January 2001 and December 2004. Coronary artery disease was excluded on the basis of clinical exami- nations, non-invasive techniques or coronary angiography. The subjects comprised 31 patients with paroxysmal supraventricular tachycardia, 36 patients with atrial fibrillation and 2 patients with atrial flutter. Results:Serum cTnI elevation was observed in 22 of the 69 patients (31.9%) with supraventricular tachycardia. Multiple regression analysis revealed interventricular septal thickness (p
[show abstract][hide abstract] ABSTRACT: Background and Objectives:Drug-eluting stents (DES) have been shown to substantially reduce both angio- graphic and clinical restenosis. Cypher ® (sirolimus-eluting stent, Cordis, Johnson and Johnson, Florida, USA) and Taxus ® (paclitaxel-eluting stent, Boston Scientific, Boston, USA) are the two most widely used DESs, and they both have distinct pharmacological properties and release kinetics. It has been not studied whether these two DESs show different angiographic outcomes when they are simultaneously implanted in the same patient. Subjects and Methods:We retrospectively analyzed the angiographic findings of the short-term follow-up in 34 patients (average age: 63 year old, 9 women) in whom both Cypher and Taxus stents were implanted at the same time for the treatment of obstructive coronary lesion. Results:There was no significant difference in the basal angiographic characteristics of the lesions that had two stents deployed in terms of the AHA/ACC classification, reference diameter, the percent diameter stenosis and minimal luminal diameter. The post-procedure results were similar between the two stents. At 6 months follow-up, the Cypher stent displayed significantly less in-stent lumen loss compared with the Taxus stent (0.16±0.04 mm vs 0.27±0.04 mm; respectively, p=0.040) and a smaller percent diameter stenosis (15.9±1.3% vs 19.9±2.2%, respectively, p=0.049). Conclusion:The Cypher stent showed significantly less luminal loss during short term follow-up compared with the Taxus stent when im- planted in the same patient. This result suggests that in a given individual patient, the Cypher stent induces less neointimal proliferation than does the Taxus stent. (Korean Circulation J 2006;36:600-604)
[show abstract][hide abstract] ABSTRACT: Imatinib mesylate is a selective Bcr/Abl kinase inhibitor and an effective anticancer agent for Bcr/Abl-positive chronic myelogenous leukemia. Most patients in chronic phase maintain durable responses; however, many in blast crisis fail to respond, or relapse quickly. Mutations within the BCR/ABL kinase domain are the most commonly identified mechanism associated with relapse. To overcome the imatinib resistance in CML, many investigators have tried to clarify molecular mechanism for imatinib resistance in cells of patients who failed to respond to imatinib. Our aim was to invesitigate underlying mechanism for imatinib resistance in SR-1 cells, which were derived from a CML patient in blast crisis. We detected the new mutation of BCR/ABL, resulting in premature termination and loss of BCR/ABL fusion protein expression, which might be possible mechanism for the resistance to imatinib in SR-1 cells.
Experimental and Molecular Medicine 11/2005; 37(5):507-11. · 2.57 Impact Factor
[show abstract][hide abstract] ABSTRACT: Previous studies have shown that ergonovine stress echocardiography (ESE) may be a valuable noninvasive tool for the diagnosis of vasospasm after the confirmation of no significant fixed stenosis.
From May 1999 to January 2002, 52 patients who presented with acute coronary syndrome (ACS) and had normal or near-normal coronary angiograms were enrolled. A 50 microg bolus of ergonovine was given intravenously at 5-min intervals, until a positive result was observed or a total dose of 350 microg was given. After the ergonovine injection, positive results were found in 25 (48%) of 52 patients: 5 (26%) of 19 with unstable angina, 10 (53%) of 19 non-ST elevation myocardial infarction (MI) and 10 (71%) of 14 patients with ST elevation MI. Using univariate analysis, the elevation of troponin concentration, clinical diagnosis of MI, and ST segment elevation on initial electrocardiographic were significantly associated with positive stress test results.
Despite the limitation that coronary spasm was not confirmed angiographically with ergonovine provocation, ESE may be a useful technique for the noninvasive diagnosis of vasospasm.
[show abstract][hide abstract] ABSTRACT: Background and Objectives:It is well known that coronary spasm can cause acute coronary syndrome (ACS, such as unstable angina or acute myocardial infarction as well as variant angina. However, the role of coronary spasm as an initial presentation in ACS is difficult to demonstrate. Therefore, we investigated the validity and safety of ergonovine echocardiography in ACS with normal coronary angiogram (CAG and suspected variant angina. Meterials and Method:From July 1999 to June 2000, 53 consecutive patients were enrolled in this study (mean age 56±10, 44 male. The clinical manifestations of the patients included acute myocardial infarction (8, unstable angina (17 and suspected variant angina (28. Ergonovine maleate was administered intravenously (50 μg at 5 minute intervals up to total cumulative dosage 350 μ g with continuous echocardiographic monitoring. The positive criterion of this test was a reversible regional wall motion abnormality seen on echocardiography. Results:This test was completed in all patients without major cardiac event or malignant arrhythmia. Fourteen patients (14/53, 26% showed a positive test:their clinical diagnosis was AMI in 2, unstable angina in 6, and variant angina in 6. Four cases were positive without chest pain or electrocardiographic change. Conclusion:Ergonovine echocardiography is a safe and useful method for the diagnosis of coronary vasospasm in ACS with normal CAG and suspected variant angina without ST segment change. ( ( ( (Korean Circulation J 2001;31( ( ((4 :405-410