Jun Hyung Kim

The effects of atorvastatin on the occurrence of postoperative atrial fibrillation after off-pump coronary artery bypass grafting surgery.

BACKGROUND Atrial fibrillation (AF) after coronary artery bypass graft (CABG) surgery is still the most common arrhythmic complication. This study evaluated whether pretreatment with atorvastatin protects against AF after off-pump CABG. METHODS One hundred twenty-four patients without a history of AF or previous statin use, who were scheduled to undergo elective off-pump CABG, were enrolled. Patients were randomized to control group (n = 62) or to atorvastatin group (n = 62) who were administered atorvastatin 20 mg/d for 3 days before the surgery. Primary outcome was the incidence of postoperative AF. Secondary outcomes were major adverse cardiac and cerebrovascular events, persistent AF at 1 month, and identification of the markers to predict inhospital postoperative AF. RESULTS The incidence of AF was significantly lower in the atorvastatin group than in the control group (13% vs 27%, P = .04). The incidence of major adverse cardiac and cerebrovascular events and persistent AF at 1 month was similar in comparisons between the groups. Postoperative peak N-terminal pro-brain natriuretic peptide levels were significantly higher in the patients with AF (P = .03). Multivariate analysis identified pretreatment with atorvastatin as an independent factor associated with a significant reduction in postoperative AF (odds ratio 0.34, P = .04). Higher postoperative peak N-terminus pro-B-type natriuretic peptide levels were associated with the development of postoperative AF (odds ratio 1.02 per 100 pg/mL, P = .03). CONCLUSIONS Pretreatment with atorvastatin significantly reduced the occurrence of postoperative AF after off-pump CABG.

The Impact of Initial Treatment Delay Using Primary Angioplasty on Mortality among Patients with Acute Myocardial Infarction: from the Korea Acute Myocardial Infarction Registry

The impact of treatment delays to reperfusion on patient mortality after primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI) is controversial. We analyzed 5,069 patients included in the Korea Acute Myocardial Infarction Registry (KAMIR) between November 2005 and January 2007. We selected 1,416 patients who presented within 12 hr of symptom onset and who were treated with primary PCI. The overall mortality at one month was 4.4%. The medians of door-to-balloon time, symptom onset-to-balloon time, and symptom onset-to-door time were 90 (interquartile range, 65-136), 274 (185-442), and 163 min (90-285), respectively. One-month mortality was not increased significantly with any increasing delay in door-to-balloon time (4.3% for ≤90 min, 4.4% for >90 min; p=0.94), symptom onset-to-balloon time (3.9% for ≤240 min, 4.8% for >240 min; p=0.41), and symptom onset-to-door time (3.3% for ≤120 min, 5.0% for >120 min; p=0.13). These time variables had no impact on one-month mortality in any subgroup. Thus, this first nationwide registry data in Korea showed a good result of primary PCI, and the patient prognosis may not depend on the initial treatment delay using the current protocols.

Outcomes of Pregnancy in Women with Congenital Heart Disease: A Single Center Experience in Korea

Pregnancy outcomes in patients with congenital heart disease have not been fully assessed in Korea. Forty-nine pregnancies that occurred in 34 women with congenital heart disease who registered at our hospital between September 1995 and April 2006 were reviewed. Spontaneous abortions occurred in two pregnancies at 6+1 and 7 weeks, and another two underwent elective pregnancy termination. One maternal death in puerperium occurred in a woman with Eisenmenger syndrome. Maternal cardiac complications were noted in 18.4%, pulmonary edema in 16.3%, symptomatic arrhythmia in 6.1%, deterioration of New York Heart Association (NYHA) functional class by ≥2 in 2.0%, and cardiac death in 2.0%. Independent predictors of adverse maternal cardiac events were an NYHA functional class of ≥3 (odds ratio [OR], 20.3), right ventricular dilation (OR, 21.2), and pulmonary hypertension (OR, 21.8). Neonatal complications occurred in 22.4% of pregnancies and included preterm delivery (16.3%), small for gestational age (12.2%), and neonatal death (2.0%). Independent predictors of adverse neonatal events were pulmonary hypertension (OR, 6.8) and NYHA functional class ≥3 (OR, 23.0). Pregnancy in women with congenital heart disease was found to be significantly associated with maternal cardiac and neonatal complications. Pre-pregnancy counseling and multidisciplinary care involving cardiologists and obstetricians are recommended for women with congenital heart disease contemplating pregnancy.

The Incidence and Predictors of Postoperative Atrial Fibrillation After Noncardiothoracic Surgery

Background and Objectives The incidence of postoperative atrial fibrillation after noncardiothoracic surgery is known to be very rare; there have been few prior studies on this topic. We evaluated the incidence, predictors, and prognosis of atrial fibrillation after noncardiothoracic surgery. Subjects and Methods Patients who underwent noncardiothoracic surgery at our medical center under general anesthesia were enrolled. We reviewed medical records retrospectively and evaluated whether the atrial fibrillation developed postoperatively or was pre-existing. Patients who had a previous history of atrial fibrillation or atrial fibrillation on the pre-operative electrocardiogram were excluded. Results Between January 2005 and December 2006, 7,756 patients (mean age: 69 years, male: 46%) underwent noncardiothoracic surgery in Samsung Medical Center and 30 patients (0.39%) were diagnosed with newly-developed atrial fibrillation. Patients who developed atrial fibrillation were significantly older and had significantly lower body mass indexes. Newly-developed atrial fibrillation was detected in 0.53% of the male patients and 0.26% of the female patients. The incidence of postoperative atrial fibrillation after an emergency operation was more frequent than that of elective operations (p<0.001). According to the multivariate analysis, age and emergency operations were independent predictors for new onset atrial fibrillation after noncardiothoracic surgery. Postoperative atrial fibrillation developed after a median of 2 days after the noncardiothoracic surgery and was associated with a longer hospitalization and increased in-hospital mortality. Four (13.3%) patients died and the causes of death were non-cardiovascular events such as pneumonia or hemorrhage. Conclusion Postoperative atrial fibrillation after noncardiothoracic surgery is a rare complication and is associated with older age and emergency operations. Patients who develop atrial fibrillation have longer hospitalizations and higher in-hospital mortality rates.

New Cu-Based Bulk Metallic Glasses with High Strength of 2000 MPa

New Cu-based bulk amorphous alloys exhibiting a large supercooled liquid region and good mechanical properties were formed in a quaternary Cu-Ni-Zr-Ti systems consisting of only metallic elements. The compositional range for the formation of the amorphous alloys that have high glass forming ability (GFA) (> 3 mm diameter) and large supercooled liquid region (> 50 K) is defined in the pseudo-ternary phase diagram Cu-Ni-(Zr, Ti). A bulk amorphous Cu54Ni6Zr22Ti18 alloy with the diameter of 6 mm can be prepared by copper mold casting. The Cu54Ni6Zr22Ti18 alloy shows glass transition temperature (Tg) of 712 K, crystallization temperature (Tx) of 769 K and supercooled liquid region (ΔTx) of 57 K. The Cu54Ni6Zr22Ti18 alloy exhibits high compressive fracture strength of about 2130 MPa with a plastic strain of about 1.5 %. The new Cu-based bulk amorphous alloy with high GFA and good mechanical properties allows us to expect the extension of application fields as a new engineering material.

Relation of left ventricular infarct transmurality and infarct size after primary percutaneous coronary angioplasty to time from symptom onset to balloon inflation.

This study was performed to evaluate the impact of time to reperfusion on infarct size and transmurality after primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). In 73 patients undergoing primary PCI for STEMI, contrast-enhanced magnetic resonance imaging was performed. Infarct size and transmurality on delayed-enhancement imaging were measured. Infarct size was not associated with symptom onset-to-balloon time (23 +/- 9% for <180 minutes, 22 +/- 9% for 180 to 360 minutes, and 24 +/- 11% for >360 minutes, p = 0.62) or door-to-balloon time (23 +/- 8% for <90 minutes, 23 +/- 10% for 90 to 120 minutes, and 22 +/- 11% for >120 minutes, p = 0.88). Infarct transmurality increased significantly with a delay of symptom onset-to-balloon time (73 +/- 22% for <180 minutes, 78 +/- 14% for 180 to 360 minutes, and 86 +/- 14% for >360 minutes, p = 0.04), but not for door-to-balloon time (79 +/- 15% for <90 minutes, 76 +/- 19% for 90 to 120 minutes, and 81 +/- 18% for >120 minutes, p = 0.62). In multivariate analysis, anterior infarction (odds ratio 4.15, 95% confidence interval 1.31 to 13.18, p = 0.02) and myocardial blush grade 0/1 (odds ratio [OR] 3.89, 95% confidence interval [CI] 1.13 to 13.51, p = 0.03) independently predicted a large infarct (infarct size > or =25%). Symptom onset-to-balloon time (OR per 30 minutes 1.26, 95% CI 1.04 to 1.53, p = 0.02) was an independent predictor of transmural infarct (average transmural extent > or =75%) and use of glycoprotein IIb/IIIa inhibitors showed a protective effect (OR 0.09, 95% CI 0.02 to 0.53, p = 0.007). In conclusion, symptom onset-to-balloon time was significantly associated with infarct transmurality but not infarct size in patients undergoing primary PCI for STEMI.

Upstream High-Dose Tirofiban Does Not Reduce Myocardial Infarct Size in Patients Undergoing Primary Percutaneous Coronary Intervention: A Magnetic Resonance Imaging Pilot Study

Primary percutaneous coronary intervention (PCI) is more effective than fibrinolytic therapy for ST‐segment elevation myocardial infarction (STEMI), but initial treatment delay to intervention is the main limitation of this strategy. Hypothesis: Upstream use of high‐dose tirofiban could reduce myocardial infarct size, using analysis of contrast‐enhanced magnetic resonance imaging (CE‐MRI).

Seizure-Like Activities during Head-Up Tilt Test-Induced Syncope

Purpose Some patients with neurally mediated reflex syncope may be misdiagnosed as epilepsy because myoclonic jerky movements are observed during syncope. The seizure-like activities during the head-up tilt test (HUT) have been rarely reported. The purpose of this study was to assess the characteristics of these seizure-like activities and evaluate whether there are differences in the clinical characteristics and hemodynamic parameters of patients with neurally mediated reflex syncope with and without seizure-like activities during HUT-induced syncope. Materials and Methods The medical records of 1,383 consecutive patients with a positive HUT were retrospectively reviewed, and 226 patients were included in this study. Results Of 226 patients, 13 (5.75%) showed seizure-like activities, with 5 of these (2.21%) having multifocal myoclonic jerky movements, 5 (2.21%) having focal seizure-like activity involving one extremity, and 3 (1.33%) having upward deviation of eye ball. Comparison of patients with and without seizure-like activities revealed no significant differences in terms of clinical variables and hemodynamic parameters during HUT. Conclusion Seizure-like activities occurred occasionally during HUT-induced syncope in patients with neurally mediated reflex syncope. The seizure-like activities during HUT might not be related to the severity of the syncopal episodes or hemodynamic changes during HUT.

Gender Difference in Patients with Recurrent Neurally Mediated Syncope

Purpose The gender difference of neurally mediated syncope is not well defined in a large patient population. The aim of this study was to evaluate the gender difference of clinical manifestations in patients with neurally mediated syncope who underwent head-up tilt test. Materials and Methods The medical records of 1,051 consecutive patients with two or more episodes of syncope, who were diagnosed as having neurally mediated syncope by head-up tilt test, were retrospectively reviewed. Results Of 1,051 patients, 497 (47.3%) patients were male and 554 (52.7%) patients were female. Female patients were experiencing syncopal episodes for longer periods of their lives (8.2 ± 9.5 years vs. 6.8 ± 9.2 years, p = 0.002) and more episodes of syncope prior to head-up tilt test (HUT) (7.2 ± 9.4 vs. 5.0 ± 6.4, p = 0.001) than male patients. Micturition syncope (20.0% vs. 5.2%, p < 0.001) was observed more frequently in male patients than in female patients. To the contrary, however, defecation syncope (16.3% vs. 9.3%, p < 0.001) was observed more frequently in female patients than in male patients. Conclusion Female patients were experiencing syncopal episodes for longer periods of their lives and more episodes of syncope than male patients. Gender difference was also noted with regard to frequency of situational syncope.

How Well Does the Target INR Level Maintain in Warfarin- Treated Patients with Non-ValvularAtrial Fibrillation?

Purpose Although warfarin is an effective oral anticoagulation (OAC) drug to reduce the risk of thromboembolism in patients with non-valvular atrial fibrillation (NVAF), long term follow-up data are scarce to be certain whether the target INR level is maintained in warfarin-treated patients in Korea. The aim of this study was to evaluate how well INRs are maintained within the target range using a new index, INR stability (= 100 × number of INRs within target range/total number of INR measurements) which we made, and to find out any correlation between thromboembolic events and INR stability. Materials and Methods This study was an observational analysis of retrospectively collected data of 129 patients with NVAF from April 2000 to December 2005 at a single tertiary hospital. All patients were registered at the anticoagulation service. Results The median duration of follow up was 2.03 years (interquartile range 1.35 - 2.96). During the follow-up period, 60.9 ± 14.9% of the INR were within the target INR range. INR stability was not significantly different between patients without and with stroke (61.2 ± 15.0% vs 53.3 ± 4.9%). Among the known factors affecting fluctuations of the INR value, the most frequent factor was noncompliance (41.8%). Conclusion The present study showed that it was not enough to maintain INR values within the target range in warfarin-treated patients with NVAF even at a tertiary hospital. Noncompliance is an important problem which interferes with maintaining target INR range.