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Objective Augmentation of left ventricular (LV) contractility and heart rate (HR) by sympathetic nerve stimulation and amelioration of heart failure by vagal nerve stimulation has been reported. However, the effects of concomitant electrical stimulation of both sympathetic and parasympathetic cardiac nerves in tissues such as those of the cardiac plexus remain unclear. This study sought to assess acute changes in cardiac function and hemodynamics in response to endovascular cardiac plexus stimulation (CPS). Methods Twelve dogs received endovascular CPS via a bipolar catheter within the right pulmonary artery. Stimulation frequency (20 Hz) and pulse width (4 milliseconds) were fixed; voltage varied (range, 15–60 V). Results Results fell into three categories: 1, no response (n = 4); 2, an increase in systemic arterial pressure that was dependent on electrode placement (n = 4); and 3, a very reproducible and stable increase in aortic pressure (n = 4). In the third group, mean systolic aortic pressures, maximum value of the first derivative of LV pressure, and LV stroke work increased with stimulation (P < 0.02 for all parameters) as did cardiac output, end-systolic elastance, and preload recruitable stroke work (P = 0.03). Systemic and pulmonary vascular resistance, central venous pressure, pulmonary arterial pressure, and HR remained unchanged (P > 0.05). Conclusions In contrast to conventional inotropic agents, endovascular CPS induced significant and selective increases in LV contractility without increasing HR. Efforts to optimize electrode placement and fixation will improve the reproducibility of endovascular CPS treatment.

A 43-year-old woman recipient of a bare metal coronary stent during an acute anterior myocardial infarction was repeatedly hospitalized with recurrent stent thrombosis (ST) over the following 3 years. Emergent coronary angiography showed a thrombus in the in-stent segment of the proximal left anterior descending artery. We repeatedly aspirated the thrombus, which immediately reformed multiple times. The discontinuation of heparin and administration of thrombolytics and argatroban, followed by repeated balloon dilatations, ended the formation of new thrombi. The patient was found to be allergic to nickel, protein S deficient and carrier of heparin-induced thrombocytopenia antibody. We discuss this case in the context of a) literature pertaining to acute coronary syndromes in the young, and b) the detailed investigations needed to identify thrombotic risk factors. Steroids may be effective to prevent recurrent ST caused by stent allergy.

Background: Quantitative assessment of left ventricular ejection fraction (LVEF) is technically difficult in patients with poor image quality (IQ). Mitral annulus velocity assessed by pulsed tissue Doppler imaging (TDI) and mitral annulus motion assessed by M-mode echocardiography has been shown to correlate with LVEF. Furthermore, mitral annulus sites are easy to identify even in patients with poor IQ. The purpose of this study was to determine whether these methods are useful for estimating LVEF in patients with poor IQ. Methods: One hundred ten patients underwent TDI and M-mode echocardiography simultaneously. Mitral annulus velocity and mitral annulus motion were obtained from each of the four mitral annulus sites. Mean mitral annular peak systolic velocities (Sm) and mean mitral annular motions (MAM) were calculated by averaging at each site. IQ was defined according to a previous report. Results: Both Sm and MAM were successfully measured in all patients. Mean Sm and mean MAM correlated with LVEF. These correlations were observed not only in patients with good IQ (p < 0.001, r = 0.61 for mean Sm; p < 0.001, r = 0.61 for mean MAM) or fair IQ (p < 0.001, r = 0.58 for mean Sm; p < 0.001, r = 0.68 for mean MAM) but also in patients with poor IQ (p < 0.05, r = 0.42 for mean Sm, p < 0.001, r = 0.61 for mean MAM). Using optimal cutoff values of mean Sm and mean MAM in each IQ group, sensitivity and specificity for identifying LVEF < 50% were comparable among three IQ groups. Conclusions: Assessment of long-axis systolic function by TDI and M-mode echocardiography enables estimation of LVEF even in patients with poor IQ.

Background Little is known about the long-term outcome of implantable cardioverter defibrillator (ICD) therapy in survivors of out-of-hospital cardiac arrest (OHCA). Methods and Results The frequency of lethal ventricular arrhythmias and whether ICD implantation can prevent recurrence of cardiac arrest were examined. Long-term (24.4±11.9 months) outcome was examined in 23 patients with OHCA who were treated with an ICD (OHCA group) and 35 patients without OHCA (non-OHCA group) who were treated with an ICD. Patients in both groups had same clinical backgrounds; however, those in the OHCA group showed a significantly lower incidence of induced ventricular arrhythmias (71%) than the non-OHCA group (96%). In the follow-up period, patients in the OHCA group had almost the same incidence of ICD discharge (30%) as patients in the non-OHCA group (40%). The rate of recurrence of ventricular fibrillation in the OHCA patients was 13%, and it was difficult to estimate the rate by induced ventricular arrhythmia. Conclusion The results suggest that ICD implantation for survivors of OHCA with favorable neurological recovery might be effective for preventing recurrence of cardiac arrest. (Circ J 2006; 70: 1128 - 1132)

Asaoka's method is a well-known method to predict settlement, and it is widely used for execution plans. Since Asaoka's method requires that the ground must be uniform, a problem in an un-uniform plane such as Haneda airport arises with respect to the application of Asaoka's method. This paper describes a method for an execution plan by introducing a notion of uniform ground, which is an approximation of uniform ground. An execution method and its parameters are assigned to some partitions of the ground, which are identified as pseudo uniform grounds by means of linear regression. Since the assignment is determined by the given parameters, even if a unskilled technical expert can plan an execution for a complicate ground.

To construct a legal knowledge base, knowledge engineers must incorporate implicit lawyer expertise. Knowledge acquisition problems still arise in legal domains. If a lawyer can construct a legal knowledge base, the problem may be solved. CPF, a logic programming language, is proposed for lawyers to express legal knowledge. Since CPF is still complicated for lawyers, however, knowledge base written by lawyers may not be executable. This paper describes a method to construct an executable knowledge base from an unexecutable knowledge base written by lawyers. Since the most expressions written by lawyers are retained, the constructed knowledge base is comprehensible to lawyers.

Aims Pre-treatment with dietary ω3 polyunsaturated fatty acids (ω3-PUFA) has been reported to reduce the incidence of new-onset atrial fibrillation (AF) following cardiac surgery. In a canine cardiac surgery model, we evaluated the impact of dietary ω3-PUFA on atrial electrophysiological properties, inflammatory markers, the atrial endothelin-1 (ET-1) system, and the expression and distribution of connexin 43. Methods and results Adult mongrel dogs received either normal chow (NC, n = 11) or chow supplemented with fish oil (FO, 0.6 g ω3-PUFA/kg/day, n = 9) for 3 weeks before surgery. A left thoracotomy was performed, and the left atrial appendage (LAA) was excised. Atrial pacing/recording wires were placed, and the pericardium/chest was closed. The atrial ratio of ω6/ω3 lipids decreased from 15–20 in NC to 2–3 in FO. FO treatment lowered pre-surgical and stabilized post-surgical arachidonate levels. Peak neutrophil to lymphocyte ratio was lower and decayed faster in FO-treated animals. Extensive inflammatory cell infiltration was present in NC atria, but was reduced in FO-treated dogs. FO-treated animals had lower post-surgical atrial expression of inducible nitric oxide synthase (iNOS) and reduced plasma ET-1. Expression of ET-1 and inositol trisphosphate receptor type-2 proteins in the LAA was also reduced. FO treatment prolonged post-operative atrial effective refractory period, slowed heart rate, and enhanced heart rate variability. Importantly, AF (>30 s) was inducible in four of six NC dogs, but no FO dogs. Conclusion Dietary FO attenuated AF inducibility following cardiac surgery by modulating autonomic tone and heart rate. FO also reduced atrial inflammation, iNOS, and ET-1 expression.

The Third International Workshop on Juris-Informatics (JURISIN 2009) was held on Nov. 19-20, 2009 at Campus Innovation Center Tokyo in Tokyo, Japan, with a support of The Japanese Society for Artificial Intelligence in association with First JSAI International Symoposia on AI (JSAI-isAI 2009). This workshop was organized to study legal issues from the perspective of informatics. Law is one of the oldest practical applications of computer science. Though lots of legal reasoning systems have been developed thus far, they were not supported by the lawyers, or they didn’t have a positive impact on jurisprudence. One of the reasons is that legal reasoning mechanisms currently implemented are too simple from the lawyer’s viewpoint. Another reason is that legal reasoning has been studied mainly from the viewpoint of logical aspects, but it has not been studied so much from the viewpoint of natural language processing. If we can bring lawyers and informatics people and natural language processing people together, we can expect great advances in both informatics and jurisprudence by implementing legal reasoning systems clear to what lawyers expect.

This paper describes a new knowledge level learning method for a problem solver. Because it is not practical to initialize a problem solver with a very large knowledge base to cope with a large variety of problems, the machine must have the capability of acquiring knowledge through solving problem in an incremental fashion. New knowledge is acquired during dialog with an instructor in problem solving operations. The accumulation of experience in problem solving enables the generalization of rules and knowledge for multiple problems. Because each new rule is formulated after solving some problem and then verified by the instructor the knowledge base will be more robust. In addition, errors in the knowledge base can be corrected by the instructor during the dialog.

Quantitative assessment of left ventricular ejection fraction (LVEF) is technically difficult in patients with poor image quality (IQ). Mitral annulus velocity assessed by pulsed tissue Doppler imaging (TDI) and mitral annulus motion assessed by M-mode echocardiography has been shown to correlate with LVEF. Furthermore, mitral annulus sites are easy to identify even in patients with poor IQ. The purpose of this study was to determine whether these methods are useful for estimating LVEF in patients with poor IQ.One hundred ten patients underwent TDI and M-mode echocardiography simultaneously. Mitral annulus velocity and mitral annulus motion were obtained from each of the four mitral annulus sites. Mean mitral annular peak systolic velocities (Sm) and mean mitral annular motions (MAM) were calculated by averaging at each site. IQ was defined according to a previous report.Both Sm and MAM were successfully measured in all patients. Mean Sm and mean MAM correlated with LVEF. These correlations were observed not only in patients with good IQ (p0.001, r = 0.61 for mean Sm; p0.001, r = 0.61 for mean MAM) or fair IQ (p0.001, r = 0.58 for mean Sm; p0.001, r = 0.68 for mean MAM) but also in patients with poor IQ (p0.05, r = 0.42 for mean Sm, p0.001, r = 0.61 for mean MAM). Using optimal cutoff values of mean Sm and mean MAM in each IQ group, sensitivity and specificity for identifying LVEF50% were comparable among three IQ groups.Assessment of long-axis systolic function by TDI and M-mode echocardiography enables estimation of LVEF even in patients with poor IQ.

Methods: We created a swine AF model using 3 weeks monensin administration to create atrial inflammation. At terminal surgery, an electrophysiological study was performed with the EnSite array system, and echocardiography was used to evaluate changes in cardiac function. Blood samples and cardiac tissues were assessed in 9 monensin-treated swine. In those with inducible AF, we created a linear ablation line in the anterior left atrium (LA) and evaluated the impact of linear ablation on episodes of paroxysmal AF. Results: Monensin created an AF substrate characterized by increased atrial but not ventricular fibrosis in swine. Monensin did not cause consistent changes in cardiac function, or plasma D-dimer or CRP levels. Electro-physiological study showed transverse conduction disturbances at the LA roof and anterior LA. In contrast, vertical conduction of LA during AF was almost simultaneous and no conduction disturbance was observed. Based on this observation, we created a linear ablation line at the roof of LA as well as at the anterior LA to LA appendage in 2 swine. AF was easily induced before, but not inducible after ablation. Conclusion: In this model, transverse conduction disturbance in the roof and anterior LA were critical for AF maintenance. Linear ablation that blocked transverse conduction in LA was very effective in preventing AF.