Yasuhiro Sasaki

Automatic Collection of Related Terms from the Web

This paper proposes a method of collecting a dozen terms that are closely related to a given seed term. The proposed method consists of three steps. The first step, compiling corpus step, collects texts that contain the given seed term by using search engines. The second step, automatic term recognition, extracts important terms from the corpus by using Nakagawas method. These extracted terms become the candidates for the final step. The final step, filtering step, removes inappropriate terms from the candidates based on search engine hits. An evaluation result shows that the precision of the method is 85%.

A comparative study on compositional translation estimation using a domain/topic-specific corpus collected from the web

This paper studies issues related to the compilation of a bilingual lexicon for technical terms. In the task of estimating bilingual term correspondences of technical terms, it is usually rather difficult to find an existing corpus for the domain of such technical terms. In this paper, we adopt an approach of collecting a corpus for the domain of such technical terms from the Web. As a method of translation estimation for technical terms, we employ a compositional translation estimation technique. This paper focuses on quantitatively comparing variations of the components in the scoring functions of compositional translation estimation. Through experimental evaluation, we show that the domain/topic-specific corpus contributes toward improving the performance of the compositional translation estimation.

Very long-term clinical outcomes after radiofrequency catheter ablation for atrial fibrillation: A large single-center experience

AIMS Radiofrequency catheter ablation (RFCA) has become widely used for drug-refractory atrial fibrillation (AF). However, there is a paucity of data on the long-term clinical outcomes after RFCA for AF. The aim of the present study was to investigate the very long-term outcomes after RFCA for AF in a large number of consecutive patients. METHODS AND RESULTS In this retrospective single-center study, we evaluated very long-term follow-up results in 1206 consecutive patients undergoing first RFCA for AF. The primary outcomes were adverse outcomes at 30-day as a safety outcome measure and event-free rates from recurrent atrial tachyarrhythmias as efficacy outcome measures. Final follow-up rate reached 99.3% with a mean follow-up duration of 5.0±2.5years. The incidence of overall 30-day adverse outcomes was 3.6% without death. The 10-year event-free rates from recurrent atrial tachyarrhythmias after the initial and last procedures were 46.9% and 76.4%, respectively. Arrhythmia recurrence occurred most commonly during the first year and decreased beyond 3-year, although it continued to occur at an annual rate of 2.0% and 1.3%, respectively, throughout the 10-year follow-up period. The cumulative 10-year incidences of stroke and major bleeding were 4.2% and 3.5%, respectively, with annual rates of 0.3%. Discontinuation rate of oral anticoagulation at 1-, 3-, and 10-year was 34.6%, 53.4%, 58.0% and 61.9%. CONCLUSIONS RFCA for AF provided favorable very long-term arrhythmia-free survival without much safety concerns. The 10-year rates of stroke and major bleeding were low even with discontinuation of oral anticoagulation in a large proportion of patients.

Percutaneous balloon valvuloplasty for bioprosthetic mitral valve stenosis

Percutaneous transcatheter mitral valvuloplasty is the indicated treatment of choice for symptomatic native mitral valve stenosis, but there have been limited reports of successful procedures of balloon valvuloplasty for bioprosthetic mitral valve stenosis. We present the case of a 62-year-old woman suffering from progressive dyspnea due to bioprosthetic mitral valve stenosis. The measured mean pressure gradient across the mitral valve was 30 mmHg and the mitral valve area was 0.73 cm2. Redoing mitral replacement was considered high risk and was refused by the patient. Percutaneous balloon valvuloplasty was performed with an Inoue balloon catheter inflated to 20 mm. The patient’s symptoms immediately improved after the procedure, with no procedure-related complications. The mean pressure gradient across the valve decreased to 19 mmHg, and the mitral valve area increased to 1.21 cm2 in postprocedural echocardiography. We conducted a literature search and identified 26 cases of balloon valvuloplasty for degenerated bioprosthetic valves. Of these, 14 cases were bioprosthetic mitral valves, and the results were favorable. However, more case reports are required to establish an evidence base for future expert recommendation of balloon valvuloplasty of prosthetic mitral valve. Meanwhile, balloon valvuloplasty will serve a niche role in highly selected patients with prosthetic mitral valve stenosis.

One of six patients with non-ischemic heart disease exhibit provoked coronary spasms: non-ischemic heart disease associated with ischemia?

OBJECTIVE The majority of cardiologists do not perform spasm provocation tests in patients with non-ischemic heart disease (non-IHD) or non-obstructive coronary artery disease (non-ob-CAD). We herein examined the frequency of provoked spasms in non-IHD and non-ob-CAD patients, including those with atypical chest pain (Aty), valvular heart disease (Val), hypertrophic cardiomyopathy (HCM), congestive heart failure (CHF), and others (Oth). METHODS & RESULTS We performed acetylcholine (ACh) spasm provocation tests over a period of 22 years (1991-2012) among 1,440 patients, including 981 IHD and 459 non-IHD subjects. A total of 43 patients with significant organic stenosis were excluded, and the remaining 416 patients with non-IHD or non-ob-CAD disease were assessed. ACh was injected in incremental doses of 20/50/80 μg into the right coronary artery (RCA) and 20/50/100/(200) μg into the left coronary artery (LCA). Positive coronary spasms were defined as transient luminal narrowing of >99%. Positive coronary spasms were noted in 17.3% of the non-IHDs patients (72/416), compared to 11.4% (15/132), 19% (8/42), 16.7% (5/30), 23.9% (16/67), and 19.3% (28/145), in the patients in the Aty, Val, HCM, CHF, and Oth groups, respectively. The rate of positive provoked spasms was higher in men than women, although not significantly [20.6% (46/223) vs. 13.4% (26/193), ns], and significantly higher in the late period (2001-2012) than in the early period (1991-2000) (36.8% vs. 7.0%, p<0.001). CONCLUSION Physicians should perform spasm provocation tests in patients with IHD as well as non-IHD with non-ob-CAD, as one of six non-IHD patients in this study exhibited provoked coronary spasms.

Complications of Pharmacological Spasm Provocation Tests

Background: We investigated the complications of spasm provocation tests, including acetylcholine (ACh) tests, ergonovine (ER) tests and adding ACh after ER tests, retrospectively. Methods: We performed 1546 ACh tests and 1114 ER tests during 23 years, including 240 adding ACh after ER tests. ACh (RCA: 20/50/(80) g, LCA: 20/50/100/(200) g) was injected incrementally over 20 seconds, whereas ER (RCA: 40 g, LCA: 64 g) was administered over 2-4 minutes. In addition, we administered adding intracoronary injection of ACh (RCA: 50/80 g, LCA: 100/200 g) after ER tests. Serious major complications were defined as ventricular fibrillation, sustained ventricular tachycardia, shock, severe hypotension (< 60 mmHg), cardiac arrest and cardiac tamponade. Results: Serious major and major complications were higher in ACh tests than ER tests (1.8% vs. 0.4%, p<0.01), whereas serious major complications were not different between ACh and ER tests (0.9% vs. 0.4%, ns). No serious major or major complications were observed in adding ACh after ER tests. Paroxysmal atrial fibrillation was not different between ACh tests and adding ACh after ER tests (16.7% vs. 12.5%, ns). Necessity of nitrates to relive provoked spasms prior to carrying other site tests were significantly higher in ER tests (6.8%) than ACh tests (2.0%) and adding ACh after ER test (2.5%). No death or irreversible complications were recognized in all three spasm provocation tests. Conclusions: Serious major complications were not different between the two agents, whereas serious major and major complications were significantly higher in ACh tests than ER tests. Although pharmacological spasm provocation tests including adding ACh after ER tests were reliable and relatively safer methods, we should perform these tests positively in the cardiac catheterization laboratory.

Sequential spasm provocation tests might overcome a limitation of the standard spasm provocation tests.

ObjectiveWe examined the clinical usefulness of sequential spasm provocation tests as follows: first, acetylcholine (ACh) test, second, ergonovine (ER) test, and finally, the ACh test following the ER test. Patients and methodsWe performed the ACh and ER tests in 461 patients (294 men, 64.4±11.3 years of age) during a 23-year period. In addition, we administered an intracoronary injection of ACh after the ER tests in 240 patients. First, ACh [right coronary artery (RCA): 20/50/(80) &mgr;g, left coronary artery (LCA): 20/50/100/(200) &mgr;g] was administered incrementally over 20 s. Second, ER (RCA: 40 &mgr;g, LCA: 64 &mgr;g) was administered over 2–4 min. If a provoked spasm did not occur, we administered an intracoronary injection of ACh (50/80 &mgr;g into the RCA and 100/200 &mgr;g into the LCA) just after the ER tests. A positive spasm was defined as more than 99% transient luminal narrowing. ResultsA positive spasm was observed in 221 (47.9%) patients including 181 ACh-positive (39.3%) and 119 ER-positive (25.8%) patients by the ACh or ER tests. In the 240 patients with a negative spasm in the ACh and ER tests, 48 (10.4%) patients developed provoked spasms on adding ACh after the ER test. The distributions of various cardiac disorders and provoked spasm vessels were similar among the three positive groups. Focal spasm was frequently observed in the ER-positive group, whereas diffuse spasm was frequently obtained in the ACh-positive group and by adding ACh after ER in the positive group. No major complications were recognized during the sequential spasm provocation tests. ConclusionSequential spasm provocation tests might overcome a limitation of standard spasm provocation tests.

Renin-angiotensin system inhibitors in patients with or without ischaemic mitral regurgitation after acute myocardial infarction

Objective Little is known about the long-term effects of renin–angiotensin system inhibitors (RASI) on cardiovascular events in patients after acute myocardial infarction (AMI) with ischaemic mitral regurgitation (IMR). The purpose of this study was to investigate the association of RASI with the incidence of adverse cardiac events in patients with or without IMR after AMI. Methods We reviewed charts of 1208 consecutive patients admitted with AMI who underwent emergency coronary angiography between 2000 and 2012. After excluding patients who died within 30 days, 551 patients were diagnosed to have mild or greater MR by transthoracic echocardiography (patients with IMR); the remaining 505 patients had no or trivial MR (non-IMR patients). Results Of the study patients, 395 (72%) patients with IMR and 403 (80%) non-IMR patients received RASI. Survival analysis showed that freedom from cardiac death and the composite of cardiac death and heart failure (HF) was significantly higher in patients with IMR receiving RASI than in those not receiving RASI (P<0.001 and P<0.001, respectively). Moreover, adjusted survival analysis using the inverse probability treatment weighting method showed a significant association of RASI therapy with reduced cardiac death (P=0.010) and the composite of cardiac death and HF (P=0.044) in patients with IMR. However, in non-IMR patients, there were no significant associations between RASI therapy and the outcome measures. Conclusions RASI therapy was associated with a lower incidence of adverse cardiac events in patients with IMR after AMI, but not in patients without IMR.

Editorial: Kounis syndrome (allergic angina and allergic myocardial infarction) for cardiologists

Aspirated thrombu s spec imens stained wit h hematoxyli n-eosin and Gimsa dem onstrate the presence of eosino phils and mast cells Chronic all ergic reacti on In 1965, cases of allergic, anaphylactic, and anaphylactoid reactions with acute myocardial infarction were first published [1]. A quarter century ago, Kounis and Zavras reported allergic angina due to histamine-induced coronary artery spasm in 1991 [2]. Allergic angina can progress to acute myocardial infarction which was named ‘‘allergic myocardial infarction’’. In 1995, Constantinides reported the potential that ordinary allergic reactions could induce coronary plaque disruptions [3]. Braunwald noted that coronary artery spasm can be provoked by allergic reactions with mediators such as histamine or leukotrienes acting on coronary vascular smooth muscle in 1998 [4]. Allergic angina and allergic myocardial infarction are referred to as ‘‘Kounis syndrome’’ and cardiologists sometimes may encounter this syndrome in the cardiac catheterization laboratory. Three variants of Kounis syndrome have been described, as shown in Fig. 1. Type I variant includes patients with normal or near normal coronary arteries without predisposing factors for coronary artery disease in whom the acute release of inflammatory mediators can induce either coronary artery spasm without increase of cardiac enzymes and troponins or coronary artery spasm progressing to acute myocardial infarction with raised cardiac enzymes and troponins. Type II variant includes patients with culprit but quiescent preexisting atheromatous disease in whom the acute release of inflammatory mediators can induce either coronary artery spasm with normal cardiac enzymes and troponins or coronary artery spasm together with plaque erosion or rupture manifesting as acute myocardial infarction. Type III variant includes patients with coronary artery stent thrombosis in whom aspirated thrombus specimens stained with hematoxylin-eosin and Giemsa demonstrate the presence of eosinophils and mast cells, respectively [5,6]. Anaphylaxis is a systemic, immediate hypersensitivity reaction caused by rapid IgE-mediated release of mediators from mast cells and basophils. Kounis syndrome is defined as the occurrence of acute coronary syndromes with conditions associated with mast

Catheter-induced Spasm in the Proximal Right Coronary Artery

Objectives The clinical characteristics in patients with catheter-induced spasm in the proximal right coronary artery (RCA) are controversial. We performed a clinical analysis of catheter-induced spasm in the RCA. Methods We retrospectively analyzed 5,296 consecutive patients who underwent diagnostic or follow-up angiography during a 26-year period. During this period, we found 40 patients with catheter-induced spasm in the RCA. We compared the clinical characteristics and procedures of cardiac catheterization in patients with catheter-induced spasm in the RCA with those in patients without such spasm. Results The frequency of catheter-induced spasm in the RCA was 0.75% (40/5,296). We performed pharmacological spasm provocation tests in 36 of 40 patients after spasm relief. Positive spasm was observed in 32 patients (88.9%), and 25 patients (78.1%) had multiple spasms. The catheter procedures, including the approach sites (radial/brachial/femoral), catheter size (4/5/6Fr) and catheter type (Judkins right/Sones/Shared/Judkins left 3.5/Amplatz) were not markedly different between the two groups. A multivariate analysis showed that positive spasm [odds ratio (OR): 7.030, 95% confidence interval (CI): 1.920-25.700], a younger age (OR: 0.937, 95% CI: 0.910-0.965) and diabetes mellitus (OR: 0.278, 95% CI: 0.083-0.928) were the determinant factors for the catheter-induced spasm. Conclusion Approximately 80% of patients with catheter-induced spasm in the proximal RCA had coronary spastic angina. Positive provoked spasm was the most powerful determinant factor for catheter-induced spasm.