Annual electrocardiograms consistent with silent progression of cardiac involvement in sporadic familial amyloid polyneuropathy: a case report

Understanding the clinical characteristics of transthyretin familial amyloid polyneuropathy (TTR-FAP) is critical for early diagnosis and timely referral for liver transplantation. Here, we describe a 52-year-old man who had slight paresthesia for four years and whose final diagnosis of TTR-cardiac amyloidosis caused by sporadic FAP was delayed despite annual electrocardiography. Curative liver transplantation was postponed because of progressive cardiac involvement. This experience highlights the difficulties associated with diagnosing TTR-FAP, especially when it is sporadic, and underscores the importance of slight changes in ECG that could indicate FAP.

An elderly case of right ventricular outflow obstruction precisely diagnosed and successfully treated with surgical repair

Congenital diseases causing an obstruction of the right ventricular outflow are difficult to precisely diagnose, especially in elderly patients. Here, we describe a 76-year-old woman who presented to our hospital with shortness of breath on exertion and was finally diagnosed as infundibular pulmonary stenosis by multiple modalities. Surgery was successfully performed and the symptom was relieved. This case underscored the usefulness of multiple modalities for the precise assessment of the right ventricular outflow obstruction and the effectiveness of surgery even in elderly patients with infundibular pulmonary stenosis.

Mutation of ARHGAP9 in patients with coronary spastic angina

Coronary artery spasm has an important function in the etiology of variant angina and other acute coronary syndromes. Abnormal activation of Rho-family GTPases has been observed in cardiovascular disorders, but the function of genetic variability in Rho-family GTPases remains to be evaluated in cardiovascular disorders. We examined the genetic variability of Rho-family GTPases and their regulators in coronary artery spasm. We performed a comprehensive candidate gene analysis of 67 single nucleotide polymorphisms with amino-acid substitution in Rho-family GTPases and their regulators in 103 unrelated Japanese patients with acetylcholine-induced coronary artery spasm and 102 control Japanese subjects without acetylcholine-induced coronary artery spasm. We noted an association of the single nucleotide polymorphism of ARHGAP9 (rs11544238, Ala370Ser) with coronary artery spasm (odds ratio =2.67). We found that ARHGAP9 inactivated Rac as RacGAP and that the mRNA level of ARHGAP9 was strongly detected in hematopoietic cells. ARHGAP9 negatively regulated cell migration. The Ala370Ser polymorphism counteracted ARHGAP9-reduced cell migration, spreading and adhesion. The Ala370Ser polymorphism in the ARHGAP9 gene is associated with coronary artery spasm. These data suggest that the polymorphism of ARHGAP9 has a critical function in the infiltration of hematopoietic cells into the endothelium and inflammation leading to endothelial dysfunction.

Restored cardiac conditions and left ventricular function after parathyroidectomy in a hemodialysis patient. Parathyroidectomy improves cardiac fatty acid metabolism assessed by 123I-BMIPP

A 62 year-old female hemodialysis patient underwent parathyroidectomy to treat secondary hyperparathyroidism. On the preoperative assessment, the plasma levels of parathyroid hormone (PTH) and B-type natriuretic peptide (BNP) were elevated. Echocardiography showed reduced left ventricular (LV) contraction. Myocardial iodine-123-15-(p-iodophenyl)-3-(R,S) methylpentadecanoic acid ((123)I-BMIPP) scintigraphy showed moderately reduced tracer uptake in the postero-inferior area on single-photon emission computed tomography and decreased washout on the planar images. After parathyroidectomy, the plasma levels of PTH and BNP decreased, followed by improvement in LV contraction. Myocardial (123)I-BMIPP scintigraphy revealed that the washout on planar images had increased, which suggests that myocardial (123)I-BMIPP scintigraphy is useful for estimating the effect of parathyroidectomy on cardiac function.

Acute and chronic effects of cardiac resynchronization in patients developing heart failure with long-term pacemaker therapy for acquired complete atrioventricular block

AIMS

We assessed the effects of cardiac re-synchronization therapy (CRT) in patients who developed otherwise unexplained heart failure (HF) during right ventricular apical (RVA)-pacing for acquired complete atrioventricular block (CAVB).

METHODS AND RESULTS

Eighteen consecutive CAVB patients with HF during RVA-pacing were assessed with haemodynamic studies immediately and 12 months after CRT-upgrade. Ten patients had idiopathic CAVB and 13 showed normal left ventricular (LV) function at RVA-pacemaker implantation. HF developed after 81 +/- 10 months. RVA-pacing duration correlated (r = 0.49, P < 0.05) with LV ejection fraction (LVEF) deterioration. Biventricular- (BiV) and LV-pacing acutely improved the systolic function comparably, but only BiV improved diastolic function. One-year post-CRT-initiation, New York Heart Association classification improved 35 +/- 3% (P < 0.05) and the number of hospitalizations decreased 85 +/- 3% (P < 0.0001). CRT decreased LV end-diastolic diameter (LVEDd) 7 +/- 2% (P < 0.01) and increased LVEF by 23 +/- 7% (P < 0.01). The CRT-induced reduction in LVEDd tended to be greater in patients with RVA-pacing for < 5 years vs. > 5 years (7.7 +/- 2.5 vs. 3.6 +/- 1.0 mm, P = 0.08).

CONCLUSION

CRT-upgrade improves the cardiac function and symptoms in CAVB patients with HF progression related to RVA-pacing. Because adverse LV-remodelling may be partly irreversible, consideration should be given to BiV- and LV-pacing upgrade as soon as possible after the indications appear, and prospective studies of the optimal timing of CRT-upgrade may be useful.

Does RV lead positioning provide additional benefit to cardiac resynchronization therapy in patients with advanced heart failure?

BACKGROUND AND OBJECTIVES

The left ventricular (LV) stimulation site is currently recommended to position the lead at the lateral wall. However, little is known as to whether right ventricular (RV) lead positioning is also important for cardiac resynchronization therapy. This study compared the acute hemodynamic response to biventricular pacing (BiV) at two different RV stimulation sites: RV high septum (RVHS) and RV apex (RVA).

METHODS AND RESULTS

Using micro-manometer-tipped catheter, LV pressure was measured during BiV pacing at RV (RVA or RVHS) and LV free wall in 33 patients. Changes in LV dP/dt(max) and dP/dt(min) from baseline were compared between RVA and RVHS. BiV pacing increased dP/dt(max) by 30.3 +/- 1.2% in RVHS and by 33.3 +/- 1.7% in RVA (P = n.s.), and decreased dP/dt(min) by 11.4 +/- 0.7% in RVHS and by 13.0 +/- 1.0% in RVA (P = n.s.). To explore the optimal combination of RV and LV stimulation sites, we assessed separately the role of RV positioning with LV pacing at anterolateral (AL), lateral (LAT), or posterolateral (PL) segment. When the LV was paced at AL or LAT, the increase in dP/dt(max) with RVHS pacing was smaller than that with RVA pacing (AL: 12.2 +/- 2.2% vs 19.3 +/- 2.1%, P < 0.05; LAT: 22.0 +/- 2.7% vs 28.5 +/- 2.2%, P < 0.05). There was no difference in dP/dt(min) between RVHS- and RVA pacing in individual LV segments.

CONCLUSIONS

RVHS stimulation has no overall advantage as an alternative stimulation site for RVA during BiV pacing. RVHS was equivalent with RVA in combination with the PL LV site, while RVA was superior to RVHS in combination with AL or LAT LV site.

84 GENE EXPRESSION DURING BLASTOCYST-TO-ELONGATED STAGE IN BOVINE EMBRYOS DERIVED FROM SOMATIC CELL NUCLEAR TRANSFER

Epigenetic modification is an important factor in the development of embryos and the production of normal offspring derived from somatic cell nuclear transfer (NTSC). Several investigators have reported aberrant gene transcription in bovine NTSC embryos at the blastocyst (BC) stage. The objectives of this study were to evaluate the gene expression in NTSC embryos, which had developed to the elongated (EL) stage, and clarify differential levels of gene transcription in the embryo disc (ED) and trophectoderm (TE) of EL embryos. Five specific mRNAs [octamer-binding transcription factor (OCT-4), interferon-τ (IFN-τ), fibroblast growth factor receptor 2 (FGF-R2), and fibroblast growth factors 2 and 4 (FGF-2 and FGF-4)] were selected. Bovine BC embryos were obtained from NTSC using calf fibroblast cells or the uterus of donor cows after AI (Vivo). Some BC embryos were transferred to recipient cows at Day 7 (Day 0 = estrus), and then EL embryos were collected by uterine flushing at Day 16. Total RNA in single BC, ED, and TE were reverse-transcribed for PCR. Quantification of mRNA abundance was performed by real-time PCR. The expression of each mRNA was normalized to the abundance of GAPDH. A total of 15 (BC) and 7 (ED and TE) samples were used in each group to analyze the gene expression. Data on mRNA expression levels were analyzed using a Kruskal–Wallis test followed by multiple pair-wise comparisons using the Scheffe method. Most embryos (87–100%) gave positive signals of OCT-4, IFN-τ, and FGF-R2, regardless of the origin and stage of the embryos. Transcript signals of FGF-4 in BC embryos derived from Vivo (100%) and NTSC (70%) were detected with higher frequencies. At the EL stage, the FGF-4 signal was detected in only ED. The transcript of FGF-2 was detected with lower frequencies (20–27%) in BC embryos, but was consistently (71–86%) detected in ED of both groups. The relative abundance of OCT-4 expression in NTSC was higher (P &lt; 0.05) than in Vivo embryos at the BC stage. In contrast, the transcript of FGF-4 at the BC stage was lower (P &lt; 0.01) in NTSC than in Vivo embryos. Transcript levels of IFN-�, FGF-R2, and FGF-2 were not significantly different in both groups at the BC stage. The amount of OCT-4, FGF-4, and FGF-2 transcripts in ED were significantly (P &lt; 0.05) higher than in TE. Transcript levels of these genes did not differ between NTSC and Vivo embryos. FGF-R2 levels were not significantly different in origins and tissue of EL embryos. In Vivo embryos, the IFN-τ level of TE was significantly (P &lt; 0.05) higher than in ED. However, the difference in the IFN-τ transcription was not observed between ED and TE in NTSC embryos. The results of an analysis of mRNA transcripts at 2 different stages of development demonstrate that bovine NTSC embryos at the BC stage show deviations in expression patterns with respect to several genes which have important roles in cell differentiation, implantation, and embryo development, but these expressions, except for IFN-τ, were modified to a normal level according to the embryo development and differentiation.

42 PREPARTUM HORMONAL CHANGES IN RECIPIENT COWS FOR SOMATIC CELL CLONED FETUSES

Placental estrogens are associated with fetal growth and development, and play important roles in the initiation of the parturition process. In the delivery of somatic cell-cloned (SC) calves, recipient cows show a weak and unclear symptom of parturition, although large offspring syndrome (LOS) frequently occurs. The mortality of calves by dystocia decreases the efficiency of SC cattle production. In this study, we examined peripheral estrone (E1), estradiol-17� (E2), estrone sulfate (E1S), and progesterone (P4) levels during preparturition in recipients of SC and in vivo calves. Recipients were administered 20 mg dexamethasone (DEX) at Days 276-288 of pregnancy, followed by 0.75-1 mg cloprostenol (PG) and 20 mg estriol 24 h later. Calves (Japanese black cattle) were delivered 2 or 3 days after the DEX administration. SC calves were delivered by cesarean section (C-sec) when LOS was suspected by rectal palpation. Blood samples of recipients [vaginal delivery of SC (Vag): n = 13; C-sec of SC: n = 8; vaginal delivery of in vivo calves (Control): n = 4] were taken at Days 257 and 271 of pregnancy, and just before DEX (-2P), PG (-1P), and parturition (0P). Blood samples of calves were taken just after delivery to analyze cortisol level. The statistical significance was analyzed by the Steel-Dwass test. Birth weight of calves was the heaviest (P &lt; 0.05) in C-sec (62 � 3 kg; n = 12); Vag calves (43 � 2 kg; n = 19) were also heavier (P &lt; 0.05) than Control calves (29 � 2 kg; n = 9). E1 levels in Control calves remained low (&lt;629 � 111 pg mL-1) until Day 271 and then increased progressively (&gt;2156 � 599 pg mL-1). E1 levels tended to be lower in Vag (&lt;1968 � 299 pg mL-1) and C-sec (&lt;1268 � 385 pg mL-1) calves at -2P, -1P, and 0P; E1 levels in C-sec calves were significantly lower (P &lt; 0.05) than in Control calves at -2P (512 � 85 pg/mL-1) and -1P (725 � 91 pg mL-1). The E2 level in Control calves increased and reached a plateau at -2P. Vag and C-sec calves showed lower E2 levels, except that the Vag level at 0P was similar to that in Control calves. The E2 level of C-sec calves (61.8 � 25.3 pg mL-1) at 0P was significantly lower (P &lt; 0.05) than that of Control calves (247.5 � 102.8 pg mL-1). E1S levels in Vag and C-sec calves increased progressively from -2P to 0P, whereas the E1S level in Control calves increased at 0P. The E1S level in Vag calves (41.1 � 4.1 ng mL-1) was significantly higher (P &lt; 0.05) than in Control calves (19.4 � 5.1 ng mL-1) at -1P. P4 levels decreased from -2P in Vag and Control calves, and from -1P in C-sec calves. The cortisol level in C-sec calves (60.1 � 19.1 ng mL-1) tended to be low compared with that in Vag (104.4 � 23.1 ng mL-1) and Control (93.4 � 15.0 ng mL-1) calves. This study revealed fetoplacental dysfunction of estrogen synthesis in the SC fetus during preparturition. Elevated E1S levels in recipients of the SC fetus, which correlated with high birth weight and agreed with previous reports for normal or plural pregnancy, might cause the reduction of E1 level. The comparable level of cortisol in Vag and Control calves indicated that SC calves had normal adrenal cortex function. Further analysis on placental estrogen synthesis and cortisol secretion in the SC fetus is necessary to clarify the cause of the prolonged gestation.

167 EXPRESSION OF INTERFERON τ IN BOVINE EMBRYOS DERIVED FROM PARTHENOGENETIC ACTIVATION

Parthenogenetic activation (PA) is a useful technique for reproductive technologies such as somatic cell nuclear transfer. Furthermore, there is a possibility of embryonic stem cell establishment deriving from PA embryos (Cibelli et al. 2002 Science 295, 819). Understanding of the ability of development and differentiation in PA embryos is important for the application. This study was designed to assess the gene expression of octamer-binding transcription factor (OCT-4) and interferon τ (IFNτ) in bovine PA embryos at the blastocyst (BC) and elongated (EL) stages, and the protein secretion of IFNτ at the EL stage. PA embryos were produced from oocytes matured in vitro (24 h), activated with Ca-ionophore (5 min) and electric pulse, and then treated with cytochalasin B and cycloheximide (5 h). In vivo-produced (Vivo) embryos were obtained non-surgically at Day 8 (Day 0 = estrus) from superovulated donor cows. PA or Vivo embryos were transferred to recipient cows (PA: 10 embryos/cow; Vivo: 1 embryo/cow) at Day 8, and then recovered non-surgically with uterine flushings at Day 16. Total RNA in single BC and EL embryos were reverse transcribed for PCR. Quantification of mRNA abundance was performed by real-time PCR. The expression of each mRNA was normalized to the abundance of GAPDH. IFNτ secretion of uterine flushings was estimated by RIA (Takahashi et al. 2005 Theriogenology 63, 1050–1060). The cleavage and blastocyst developmental rates of PA oocytes were 65.8 and 29.7%, respectively. Most embryos had positive signals of OCT-4 and IFNτ regardless of the origin and stage of embryos. The relative abundance (mean � SEM) of OCT-4 expression in PA and Vivo embryos dropped to its lowest level (1.78 � 0.32 and 1.14 � 0.45, respectively) at the EL stage, and it was significantly lower than that at the BC stage (1018.87 � 148.69 and 696.29 � 151.80, respectively; P &lt; 0.05). The transcript level of OCT-4 was not significantly different between PA and Vivo embryos at both stages. Although the transcript level of IFNτ in PA and Vivo embryos increased significantly at the EL stage (0.36 � 0.06 and 7.68 � 2.01, respectively) from the BC stage (0.03 � 0.01 and 0.01 � 0.004, respectively; P &lt; 0.05), that in PA embryos was significantly lower than that in Vivo embryos at the EL stage (P &lt; 0.01). The total amount (mean � SEM) of IFNτ in uterine flushings from cows with transferred PA embryos was 3.38 � 0.35 �g (the number of embryos in each uterine flushing was unknown), and it was low compared with that from cows with Vivo embryos (13.40 � 3.03 �g). Our results indicate that bovine PA embryos have the ability to secrete IFNτ in the uteri of recipient cows at the EL stage, and there is a similar expression pattern of OCT-4 for Vivo embryos.

170 EXPRESSION PROFILE AND PROTEIN SECRETION OF BOVINE INTERFERON τ ON DAYS 12 TO 28 IN EARLY PREGNANCY

Bovine interferon (bIFN) τ has been implicated as a mediator of maternal recognition of pregnancy in cattle. Ovine (o) and bIFNτ expression show temporal patterns until implantation begins (Farin et al. 1990 Biol. Reprod. 43, 210–218); therefore, the expression peaks of bIFNτ are not well understood. This study aimed to investigate the expression profile of mRNA and protein secretion of bIFNτ in conceptuses obtained from cows on Days 12 to 28 in early pregnancy. Induction of superovulation and recipient synchronization were achieved by previously reported methods (Hirayama et al. 2004 Theriogenology 62, 887–896). Embryos were recovered non-surgically on Day 8 (Day 0 = estrus). Subsequently, recovered embryos were singly transferred to recipients immediately upon evaluation. Bovine conceptuses and uterine flushings were collected non-surgically from embryo-transferred cows on Days 12 (n = 2), 14 (n = 6), 16 (n = 5), 18 (n = 4), and 20 (n = 5) with MEM. On Days 22 (n = 3), 24 (n = 5), and 28 (n = 2), bovine conceptuses were recovered within 30 min after slaughter by flushing the uterus with PBS supplemented with 0.1% BSA. Uterine flushings were also collected from 6 cows in the control group on Day 16 of the estrous cycle. Conceptuses for collection of RNA were processed individually and stored at -80�C until analysis. The flushing was centrifuged at 1800g and 4�C for 30 min to remove cellular debris, and stored at -30�C for subsequent measurement of bIFNτ. Total RNA in conceptuses were reverse transcribed for PCR. Quantification of mRNA abundance was performed by real-time PCR. The expression of each mRNA concentration was normalized to the abundance of GAPDH. BIFNτ contents of the uterine flushings were measured by RIA (Takahashi et al. 2005 Theriogenology 63, 1050–1060). Intra-assay and inter-assay CVs were 11.0 and 8.5%, respectively. Transcripts of bIFNτ were detected in all samples from Days 12 to 28; the expression of mRNA increased remarkably from Day 16 (mean � SEM, 2.15 � 0.66) to Day 18 (9.62 � 4.09), and then declined on Day 20 (3.42 � 0.86). Protein detected on Day 16 was 13.3 � 3.02 �g. An increase of bIFNτ secretion was observed between Day 18 (39.8 � 20.62 �g) and Day 20 (71.9 � 17.36 �g); thereafter it decreased on Day 22 (27.2 � 2.83 �g). BIFNτ displayed a pattern of expression similar to that of oIFNτ, with mRNA expression peaking around Day 18 (ovine, Days 12/13) and protein secretion on Day 20 (ovine, Days 15/16), thereby reflecting the comparatively later time frame of maternal recognition of pregnancy in cattle. These results indicate that the expression and secretion profiles of bIFNτ show temporal and spatial patterns in early pregnancy.

204 RELATIONSHIP BETWEEN RESPIRATORY ACTIVITY AND THE PREGNANCY RATE OF BISECTED BOVINE EMBRYOS IN VIVO

Oxygen consumption is an important indicator of the metabolic activity of living cells, which may provide valuable information for evaluating embryo quality. We have found that the bovine embryos with high oxygen consumption possess stronger potential for further development. However, the relationship between respiratory activity and the pregnancy rate of embryos is still unclear. In this study, we investigated the respiration rates of bisected bovine embryos and the pregnancy rates of demi-embryos after embryo transfer. Compact morula-stage embryos were bisected evenly by micro glass needle. One hundred bisected embryos were incubated for 24 h in embryo culture medium (IVD101; Research Institute for the Functional Peptides, Yamagata, Japan) at 39�C under 5% CO2, 5% O2, 90% N2. After the incubation, demi-embryos were classified into 2 groups: blastocoel-formed (BC) and blastocoel-not-formed (CM) embryos. Oxygen consumption rates of demi-embryos were measured by scanning electrochemical microscopy (SECM; Hokuto Denko Corporation, Tokyo, Japan). Within 3 h after the measurement, 80 demi-embryos were transferred into recipient cows (one demi-embryo/one recipient) at 7–8 days after estrus. Recipient cows were diagnosed for pregnancy by ultrasonography approximately 40 days after estrus. Statistical difference was analyzed by Tukey's post-hoc test and chi-square test. A total of 27 recipient cows became pregnant; the pregnancy rates for cows with CM and BC demi-embryos were 40.6% (13/32) and 29.2% (14/48), respectively. Mean oxygen consumption rates (� 10-14 mol s-1) in pregnant and non-pregnant cows were 0.47 and 0.39 for CM demi-embryos and 0.63 and 0.52 for BC demi-embryos, respectively. Retrospective analysis showed that the respiratory activity of demi-embryos in the pregnant group was higher than those in the non-pregnant group. In particular, the pregnancy rates for demi-embryos with respiratory activity higher than 0.35 in CM and 0.40 in BC groups were 52.0% (13/25) and 35.9% (14/39), respectively. On the other hand, cows with demi-embryos having an oxygen consumption rate under 0.35 in CM (n = 7) and 0.40 in BC (n = 9) groups did not become pregnant. These results demonstrated that bovine demi-embryos with higher respiratory activity showed a high pregnancy rate after embryo transfer. It is generally known that the pregnancy rate after the transfer of bisected embryos is lower than that of whole embryos. The measurement of oxygen consumption by SECM procedures is a useful tool to assess the quality of pre-implantation embryos and may contribute to the improvement of the success rate for bisected embryo transfer.

Predictors of in-hospital delay to reperfusion in patients with acute myocardial infarction in Japan

The purpose of this study was to identify factors associated with in-hospital delay in patients with acute myocardial infarction (AMI) in Japan. In this observational study, 155 consecutive patients admitted with AMI to one of five urban hospitals were studied. The median door-to-needle time and door-to-catheterization-laboratory time was 19 min and 60 min, respectively. Three variables predicted door-to-catheterization-laboratory times >/= 60 min: failing to call an ambulance, direct admission to the hospital, and absence of diaphoresis (p < 0.05). These findings support the need for public education emphasizing the importance of calling an ambulance for AMI symptoms. Moreover, Japanese physicians should be aware that admitting patients directly to the hospital and bypassing the Emergency Department might increase delay to treatment.

Trajectory of prehospital delay in patients with acute myocardial infarction in the Japanese health care system

OBJECTIVE

The purpose of this study was to understand the trajectory of prehospital delay in patients with acute myocardial infarction (AMI) in the Japanese health care system, which offers patients a choice between seeking treatment in a neighborhood clinic/small hospital (clinic group) or a large hospital with comprehensive cardiac services, including a cardiac catheterization laboratory (hospital group).

METHODS

In this cross sectional study, 155 consecutive patients admitted with AMI to one of 5 urban hospitals in Japan were interviewed within 7 days after admission.

RESULTS

The median total prehospital delay time in the clinic group (n=84) was significantly longer than the hospital group (n=71) (6 h and 48 min vs 2 h and 9 min, p<.001). Patients with severe chest pain were significantly less likely to seek treatment at a clinic/small hospital than at a large hospital compared to patients with mild or moderate symptoms (OR 0.85, 95% CI: 0.75, 0.97). Patients who did not interpret their symptoms as cardiac in origin were significantly more likely to seek treatment at a clinic/small hospital than at a large hospital compared to patients who interpreted their symptoms as cardiac in origin (OR 3.32, 95% CI: 1.56, 7.10). After controlling for demographic and medical history, patients in the clinic group were 3.69 times (95% CI: 1.28, 10.66) less likely to receive any reperfusion therapy compared to patients in the hospital group.

CONCLUSIONS

Findings support the need for public education in Japan that focuses on the appropriate response to AMI symptoms. Moreover, regional AMI networks need to be instituted to provide for early transfer for PCI from clinic/small hospitals to tertiary centers.

Do Japanese workers who experience an acute myocardial infarction believe their prolonged working hours are a cause?

BACKGROUND

Cardiovascular disease related to excessive work/job stress has been a significant social concern for the Japanese public. Therefore, we conducted a cross-sectional study to (1) compare job stress levels between patients with acute myocardial infarction (AMI) patients and healthy workers, and (2) examine the types of stresses associated with patients' causal belief of AMI among patients with AMI.

METHODS

Forty-seven patients admitted to the hospital with AMI and 47 healthy workers visiting a hospital for their annual physical examination were recruited in Japan. Both groups were employed full time and matched on age and gender. Job stress was assessed by the Brief Job Stress Questionnaire, which consists of four subscales: job demand, job control, support from supervisors, and support from coworkers. Causal belief was assessed by a semi-structured interview.

RESULTS

Compared with healthy workers (50.7+/-8.6 h), AMI patients worked significantly longer hours per week (58.3+/-15.0 h) prior to their AMI. Among AMI patients, 38% reported that job stress might have contributed to their AMI. AMI patients who reported acute stressful events at work during the month prior to AMI were 6.88 times (95% CI: 1.84, 25.75) more likely to believe that job stress/overwork caused their AMI after controlling for working hours per week and age.

CONCLUSIONS

Like other known cardiac risk factors, it is important for clinicians to assess patient's excessive working hours. The education and counseling of patients following AMI must take into consideration long working hours, acute stressful events at work, and the patient's perceived view of job stress.

Radiation safety design for the J-PARC Project

The High-Intensity Proton Accelerator Project, named J-PARC, is in progress, with the aim of enabling studies on the latest basic science and the advancement of nuclear technology. In the project, a high-energy proton accelerator complex with the world's highest instantaneous intensity is under construction. In order to establish a reasonable shielding design, both simplified and detailed design methods were used in the shielding design of J-PARC. This paper reviews the present status of the radiation safety design study for J-PARC.

Arrangement of high-energy neutron irradiation field and shielding experiment using 4 m concrete at KENS

An irradiation field of high-energy neutrons produced in the forward direction from a thick tungsten target bombarded by 500 MeV protons was arranged at the KENS spallation neutron source facility. In this facility, shielding experiment was performed with an ordinary concrete shield of 4 m thickness assembled in the irradiation room, 2.5 m downstream from the target centre. Activation detectors of bismuth, aluminium, indium and gold were inserted into eight slots inside the shield and attenuations of neutron reaction rates were obtained by measurements of gamma-rays from the activation detectors. A MARS14 Monte Carlo simulation was also performed down to thermal energy, and comparisons between the calculations and measurements show agreements within a factor of 3. This neutron field is useful for studies of shielding, activation and radiation damage of materials for high-energy neutrons, and experimental data are useful to check the accuracies of the transmission and activation calculation codes.

The angiotensin II receptor blocker candesartan cilexetil reduces neointima proliferation after coronary stent implantation: a prospective randomized study under intravascular ultrasound guidance

OBJECTIVES

The purpose of this study was to evaluate whether an angiotensin II receptor blocker, candesartan cilexetil, reduced neointima formation after coronary stent implantation by way of serial intravascular ultrasound analysis.

BACKGROUND

Previous experimental studies have suggested that angiotensin II receptor blocker reduced neointima formation after vascular injury. However, it is unclear whether candesartan cilexetil has a similar effect on human coronary artery.

METHODS

We recruited 50 consecutive patients with stable angina pectoris and 60 stenotic lesions. Patients were prospectively randomized into 2 groups: (1) 25 patients with 31 lesions received candesartan cilexetil (4-12 mg/d), and (2) 25 patients with 29 lesions did not receive the drug. Follow-up intravascular ultrasound was performed 6 m after the stent implantation. Cross-sectional images were obtained at 1-mm intervals within the stent, and the stent volume (SV), lumen volume (LV), and neointima volume (NV = SV - LV) were calculated using Simpson's rule. The percentage neointima volume obstruction (%NV) was calculated as NV/SV x 100.

RESULTS

Clinical and angiographic backgrounds were comparable between the 2 groups. At follow-up, the candesartan group had smaller SV and larger LV (SV, 156.3 +/- 53.7 vs 165.4 +/- 61.8 mm3 , ns; LV, 122.2 +/- 49.0 vs 113.1 +/- 45.5 mm3 , ns), and significantly smaller NV and significantly smaller %NV than the control group (NV, 34.2 +/- 16.6 vs 52.3 +/- 32.6 mm3 , P < .01; %NV, 22.7 +/- 10.9% vs 31.3 +/- 13.4%, P < .01).

CONCLUSIONS

Candesartan treatment decreases neointima formation and hence may reduce in-stent restenosis.

Experimental determination of minimal stimulation current and period for electrical thrombosis in dogs

SUMMARY

Endovascular surgery has been proposed as an alternative treatment for cerebral aneurysms. However, for wide neck and large sized lesions it is very difficult to obtain complete occlusion and tissue organization. The present study was conducted to examine the efficacy of electrical thrombosis for cerebral aneurysms and parent arterial occlusions using Interlocking Detachable Coils (IDCs), focusing on the minimum current volume and stimulation time required for stable electrical thrombosis formation. We used ten mixed-breed adult dogs (in the study body weights 9-12 kg; males: 5, females: 5). Guiding catheter sand microcatheters were introduced into both sides of the distal external carotid artery (ECA) and placed at the same level. To prevent migration, IDCs (4 mm x 12 cm) were placed in the ECA without being detached. After confirming no vessel occlusion, we applied a positive current (2-6 mA) to the coil on one side and performed angiography every ten minutes to observe whether vessel occlusion with electrothrombosis had occurred. It was determined that to achieve complete occlusion of the external carotid arteries in mixedbreed dogs, a minimum stimulation current of 4mA and a minimum stimulation time of ten to 20 minutes are required.

Illness attribution among Japanese patients with acute myocardial infarction

OBJECTIVE

The purpose of this study was to describe causal attribution of acute myocardial infarction (AMI) in Japanese patients.

DESIGN

A cross-sectional study design was used.

SETTING

The setting for this study was 5 hospitals in urban areas in Japan.

SAMPLE

A convenience sample of 155 patients admitted with AMI was used.

MEASURES

Causal attribution was assessed by a semi-structured interview. Known risk factors were assessed by medical record review and patient interview.

RESULTS

Twenty-two different primary causes for AMI were identified. Patients most commonly cited smoking, stress, and diet as risk factors. Except for smoking, Japanese patients did not identify their cardiac risk factors as a cause of their AMI. Controlling for sociodemographic characteristics, patients with a recorded history of coronary heart disease were significantly less likely to attribute their cardiac risk factors to their AMI (P <.05).

CONCLUSIONS

Effective education and counseling of patients after an AMI must be coupled with their view of what factors put them at risk for future AMIs.

Incremental predictive value of myocardial scintigraphy with 123I-BMIPP in patients with acute myocardial infarction treated with primary percutaneous coronary intervention

PURPOSE

It is unclear whether 123I-labelled beta-methyl iodophenyl pentadecanoic acid (123I-BMIPP) myocardial scintigraphy adds further predictive value for future cardiac events compared with the variables obtained during cardiac catheterisation in patients with acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention (PCI). We therefore investigated whether 123I-BMIPP imaging in patients with AMI treated by primary PCI was useful in predicting future cardiac events.

METHODS

One hundred and fifty-nine patients with AMI who were treated with primary PCI and underwent left ventriculography (LVG) on admission underwent 201Tl and 123I-BMIPP myocardial scintigraphy. Scintigrams were visually classified, and the total defect score (TDS) was calculated. Major adverse cardiac events (MACE) were defined as cardiac death including sudden death, congestive heart failure and recurrence of acute coronary syndrome. Patients were followed up for a mean of 34.5 months (12-63 months).

RESULTS

Twenty-six patients had MACE. Kaplan-Meier analysis indicated that patients with the top 50% of 123I-BMIPP TDSs had a significantly higher rate of MACE (P=0.007). Patients with mismatch between 201Tl and 123I-BMIPP images also had significantly more MACE (P=0.02). In the prediction of MACE, the global chi-square value was 5.2 (P=0.001) based on LVEF (<45%) and the number of diseased vessels (two or three). Adding 123I-BMIPP TDS and the mismatch improved the global chi-square value (chi2=7.2)

CONCLUSION

Myocardial scintigraphy using 201Tl and 123I-BMIPP predicts future cardiac events in patients with AMI treated with primary PCI, and provides additional predictive value compared with the variables obtained with cardiac catheterisation alone.