Jin-Oh Choi

Indications of neutrino oscillation in a 250 km long-baseline experiment.

The K2K experiment observes indications of neutrino oscillation: a reduction of nu(mu) flux together with a distortion of the energy spectrum. Fifty-six beam neutrino events are observed in Super-Kamiokande (SK), 250 km from the neutrino production point, with an expectation of 80.1(+6.2)(-5.4). Twenty-nine one ring mu-like events are used to reconstruct the neutrino energy spectrum, which is better matched to the expected spectrum with neutrino oscillation than without. The probability that the observed flux at SK is explained by statistical fluctuation without neutrino oscillation is less than 1%.

Longitudinal 2D strain at rest predicts the presence of left main and three vessel coronary artery disease in patients without regional wall motion abnormality.

AIMS Non-invasive echocardiographic detection of coronary artery disease (CAD), even in left main or three-vessel CAD, usually requires a stress test since regional wall motion abnormalities (RWMA) are not always evident at rest. Strain is a more sensitive parameter of myocardial systolic function and may be abnormal in patients with severe CAD. METHODS AND RESULTS We evaluated whether peak systolic longitudinal strain (PSLS) of left ventricle using 2D speckle tracking method might be useful for screening of severe CAD. One hundred and eight patients who underwent echocardiography and coronary angiography were evaluated. Patients were grouped according to the coronary angiographic findings as follows; high-risk group with left main or three-vessel CAD (n = 38), low-risk group with one- or two-vessel CAD (n = 28), and control group without CAD (n = 30). PSLSs of all left ventricular segments were obtained successfully in 96 (89%) patients. None had RWMA at resting echocardiogram. PSLS was significantly reduced, especially in mid- and basal segments, in the high-risk group. Receiver operating characteristic (ROC) curve analysis demonstrated that mid- and basal PSLSs could effectively detect patients with severe CAD (area under ROC curve = 0.83, 95% CI 0.75-0.91). According to ROC curve analysis, -17.9% appears to be a helpful cutoff value for discriminating those with severe CAD (specificity 79% and sensitivity 79%). CONCLUSION PSLS at rest was significantly lower in patients with left main or three-vessel CAD without RWMA, and might be useful for identifying patients with a severe CAD.

Endoscopic submucosal dissection or transanal endoscopic microsurgery for nonpolypoid rectal high grade dysplasia and submucosa-invading rectal cancer.

BACKGROUND AND STUDY AIMS Transanal endoscopic microsurgery (TEM) has been shown to be highly effective for early rectal cancer, and endoscopic submucosal dissection (ESD) has been introduced to treat noninvasive colorectal neoplasia. The aim of this study was to compare the outcomes of ESD and TEM for superficial early rectal cancer. PATIENTS AND METHODS We retrospectively analyzed 63 patients with nonpolypoid rectal high grade dysplasia or submucosa-invading cancer who were treated with ESD or TEM, and compared clinical outcomes and safety between the treatment groups. RESULTS 30 patients underwent ESD and 33 underwent TEM. For ESD compared with TEM, en bloc resection rates were 96.7% vs. 100% (P = 0.476) and R0 resection rates were 96.7 % vs. 97.0 % (P = 1.000). There were no cases of local recurrence or distant metastasis in either group. Antibiotics were required in 11 patients (36.7%) in the ESD group and 33 (100%) in the TEM group (P < 0.001). There was no difference in net procedure time although ESD was associated with shorter total procedure time and hospital stay than TEM, with mean (standard deviation [SD]) 84.0 (51.2) vs. 116.4 (58.5) min (P = 0.0023), and 3.6 (1.2) vs. 6.6 (3.5) days (P < 0.001), respectively. There were no significant differences in complications between the two groups. CONCLUSIONS Both ESD and TEM are effective and oncologically safe for treating nonpolypoid rectal high grade dysplasia and submucosa-invading cancers. ESD has the additional advantages of minimal invasiveness and avoidance of anesthesia. Therefore, ESD could be recommended as a treatment option for superficial early rectal cancers.

Pulse wave velocity is more closely associated with cardiovascular risk than augmentation index in the relatively low-risk population

Pulse wave velocity (PWV) and augmentation index (AI) are both indirect indicators of arterial stiffness, which is an independent predictor of morbidity and mortality in cardiovascular diseases. The aim of this study was to assess the association between carotid AI (CAI), carotid-femoral PWV (CFPWV), and Framingham risk score (FRS), and to evaluate the factors determining CAI and CFPWV. Carotid AI and CFPWV were measured by applanation tonometry in 177 consecutive subjects without evidence of significant cardiovascular disease. Correlations between CAI and FRS and CFPWV and FRS were analyzed and major determinants of CAI and CFPWV were assessed. The mean age was 60.5 ± 11.9 years and 112 (63%) of study patients were men. There was a significant association between CFPWV and FRS (r = 0.417, P < 0.001) and a weaker but also significant relation between CAI and FRS (r = 0.267, P < 0.001). CFPWV was significantly related to FRS in both men and women (P < 0.001 in both sexes), whereas the relation between CAI and FRS was significant only in women (P < 0.001). Our results suggest that CFPWV may be associated with CVD risk irrespective of sex, whereas CAI may be associated with CVD risk in women only.

Plasma transforming growth factor β1 as a biochemical marker to predict the persistence of atrial fibrillation after the surgical maze procedure

OBJECTIVES The Cox maze procedure was developed as a surgical treatment for atrial fibrillation. However, atrial fibrillation recurs in some patients, and atrial remodeling in the form of fibrosis can lead to perpetuation of atrial fibrillation. To identify the predictor of the persistence of atrial fibrillation after the maze procedure using cryoablation, we evaluated the preoperative plasma transforming growth factor beta1. We also examined the correlations between plasma transforming growth factor beta1 levels and the degree of atrial fibrosis. METHODS Preoperative plasma transforming growth factor beta1 levels were measured in 86 consecutive patients (age, 54 +/- 12 years) who underwent both the open heart operation for valvular heart disease and the surgical maze procedure with cryoablation for persistent atrial fibrillation. We measured the degree of fibrosis from the tissue of the left atrium. RESULTS At 1 years follow-up, 10 of 86 patients had persistent atrial fibrillation. Patients with persistent atrial fibrillation had higher preoperative plasma transforming growth factor beta1 levels than the patients with sinus rhythm (0.44 +/- 0.29 vs 0.32 +/- 0.15 ng/mL, P = .03). Patients with persistent atrial fibrillation had higher mRNA expressions of collagen III and lower mRNA expressions of atrial natriuretic peptide than those with sinus rhythm, and the plasma transforming growth factor beta1 levels correlated with the degree of fibrosis in the left atrium (r = 0.497, P = .022). Multiple logistic regression analysis revealed that plasma transforming growth factor beta1 levels were independently associated with the postoperative persistence of atrial fibrillation at 1 years follow-up. CONCLUSIONS Preoperative plasma transforming growth factor beta1 levels could be used to predict the persistence of atrial fibrillation at 1 years follow-up after the surgical maze procedure by using cryoablation. Preoperative plasma transforming growth factor beta1 levels were correlated with the degree of fibrosis in the left atria of patients with mitral valvular heart disease.

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.

Near muon range detector for the K2K experiment: Construction and performance

A muon range detector (MRD) has been constructed as a near detector for the KEK-to-Kamioka long-baseline neutrino experiment (K2K). It monitors the neutrino beam properties at the near site by measuring the energy, angle and production point of muons produced by charged-current neutrino interaction. The detector has been working stably since the start of the K2K experiment.

SUrvey of Guideline Adherence for Treatment of Systolic Heart Failure in Real World (SUGAR): A Multi-Center, Retrospective, Observational Study

Background Clinical practice guidelines have been slowly and inconsistently applied in clinical practice, and certain evidence-based, guideline-driven therapies for heart failure (HF) have been significantly underused. The purpose of this study was to survey guideline compliance and its effect on clinical outcomes in the treatment of systolic HF in Korea. Method and Results The SUrvey of Guideline Adherence for Treatment of Systolic Heart Failure in Real World (SUGAR) trial was a multi-center, retrospective, observational study on subjects with systolic HF (ejection fraction <45%) admitted to 23 university hospitals. The guideline adherence indicator (GAI) was defined as a performance measure on the basis of 3 pharmacological classes: angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor II blocker (ARB), beta-blocker (BB), and aldosterone antagonist (AA). Based on the overall adherence percentage, subjects were divided into 2 groups: those with good guideline adherence (GAI ≥50%) and poor guideline adherence (GAI <50%). We included 1319 regional participants as representatives of the standard population from the Korean national census in 2008. Adherence to drugs at discharge was as follows: ACEI or ARB, 89.7%; BB, 69.2%; and AA, 65.9%. Overall, 82.7% of the patients had good guideline adherence. Overall mortality and re-hospitalization rates at 1 year were 6.2% and 37.4%, respectively. Survival analysis by log-rank test showed a significant difference in event-free survival rate of mortality (94.7% vs. 89.8%, p = 0.003) and re-hospitalization (62.3% vs. 56.4%, p = 0.041) between the good and poor guideline-adherence groups. Conclusions Among patients with systolic HF in Korea, adherence to pharmacologic treatment guidelines as determined by performance measures, including prescription of ACEI/ARB and BB at discharge, was associated with improved clinical outcomes.

Short- and long-term outcomes depending on electrical dyssynchrony markers in patients presenting with acute heart failure: clinical implication of the first-degree atrioventricular block and QRS prolongation from the Korean Heart Failure registry.

BACKGROUND Prolongations of PR interval and QRS duration on 12-lead electrocardiogram are associated with atrioventricular and interventricular/intraventricular dyssynchrony, respectively. However, their clinical significance remains unclear in real-world heart failure (HF) population. We assessed whether the presence of first-degree atrioventricular block and/or QRS prolongation (≥120 ms) is associated with worse short- and long-term outcomes in patients with acute HF. METHODS The Korean Heart Failure is a nationwide registry of 3,200 consecutive patients presenting with acute HF at 24 centers in South Korea between June 2004 and April 2009. We selected 1,986 patients with sinus rhythm and divided them into 4 groups depending on the presence of first-degree atrioventricular block and/or QRS prolongation; ED_Neither (n = 1,347), ED_PR (n = 217), ED_QRS (n = 329), and ED_Both (n = 93) groups, respectively. RESULTS During the median follow-up of 18.2 months, overall death rate (17%, 22%, 20%, and 29%, P < .01) tended to rise with increasing number of electrical dyssynchrony markers. Patients in ED_Both group showed worst outcomes regarding the requirement of invasive managements during the index admission, in-hospital mortality, postdischarge death/rehospitalization, and cardiac device implantation. In time-dependent Cox regression analyses, presence of both PR >200 ms and QRS ≥120 ms was independently associated with in-hospital death (P < .01), postdischarge death/rehospitalization (P = .03), cardiac device implantation (P < .01), and overall death (P < .01). CONCLUSIONS A combined analysis of electrical dyssynchrony markers (PR prolongation and QRS widening) might be useful for short- and long-term risk stratifications of patients with acute HF.

Antiviral Activity of Coxsackievirus B3 3C Protease Inhibitor in Experimental Murine Myocarditis

BACKGROUND We investigated the efficacy of a 3C protease inhibitor (3CPI) in a murine coxsackievirus B3 (CVB3) myocarditis model. CVB3 is a primary cause of viral myocarditis. The CVB3 genome encodes a single polyprotein that undergoes a series of proteolytic events to produce several viral proteins. Most of this proteolysis is catalyzed by the 3C protease (3CP). METHODS AND RESULTS By way of a micro-osmotic pump, each mouse received 50 mM 3CPI in 100 μL of 100% dimethyl sulfoxide (DMSO) during a 72-hour period. On the day of pump implantation, mice (n = 40) were infected intraperitoneally with 10(6) plaque-forming units of CVB3. For the infected controls (n = 50), the pump was filled with 100% DMSO without 3CPI. The 3-week survival rate of 3CPI-treated mice was significantly higher than that of controls (90% vs 22%; P < .01). Myocardial inflammation, viral titers, and viral RNA levels were also reduced significantly in the 3CPI-treated group compared with these measures in the controls. CONCLUSIONS The protein-based drug 3CPI inhibited the activity of 3CP of CVB3, significantly inhibited viral proliferation, and attenuated myocardial inflammations, subsequent fibrosis, and CVB3-induced mortality in vivo. Thus, this CVB3 3CPI has the potential to be a novel therapeutic agent for the treatment of acute viral myocarditis during the viremic phase.