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Electron cyclotron emission (ECE) can be used to determine the electron temperature profile in magnetized plasmas. The complex structure of the magnetic field configuration in the Large Helical Device (LHD) [M. Fujiwara et al., J. Fusion Energy 15, 7 (1996)] complicates the analysis of the ECE spectrum. The magnetic field is a nonmonotonous function of the radius and has a very large shear. The effects of the magnetic-field shear on the polarization of the ECE spectrum have been numerically and experimentally analyzed. For a high enough density (n[sub e]>1.0x10[sup 19] m[sup -3]) the polarization is found to rotate with the sheared magnetic field, yielding only a negligible mode conversion. Experiments on the polarization have been carried out at LHD. X-mode emission was detected under a specific angle, in agreement with the numerical predictions. The elliptically polarized ECE emission showed a very strong O-mode component (70% of X-mode), that can be attributed to the effect of wall reflections. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A real-time processing system for the two-color CO2 laser interferometer on the JT-60SA has been developed for density feedback control. The system has a novel feature that can detect fringe jumps due to off-normal events, such as loss detection due to displacement of the beam axis and changes in the laser wavelengths. Because a phase change due to the JT-60SA plasma is smaller than π/2, corresponding to the line-integral electron density NL of ∼6×1019 m-2 in a short interval of 500 ns, the threshold of the fringe jump detection is decided to be π/2. Hence, off-normal events can be detected from a fringe jump, leading to the abort of the real-time feedback control. In the density feedback control of the JT-60SA plasma, the system is employed as a density monitor, with NL being successfully controlled at 16.8% ± 6.6% lower than the reference., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

A thermal image plate (TIP) using ceramic luminescence materials has been developed in order to visualize a beam spot of a CO 2 laser which is used as a light source of an interferometer developed in JT-60SA. By using CaAlSiN 3 :Eu 2+ (CASN), the TIP was developed, and its property was assessed. A CASN TIP was able to visualize the invisible CO 2 laser beam as a negative image. The beam diameter and the stability of the beam axis measurement obtained with the CASN TIP were approximately the same as that obtained with a commercial TIP. Furthermore, the time response of the CASN TIP at the best was approximately the same as that of the commercial TIP. The CASN TIP which had the highest time response was applied to the beam axis stabilizer, and then the beam axis stabilization was successfully performed in 2 h.

Background: The epidemiological patterns of musculoskeletal injuries or disorders in military personnel have not been well documented and a better understanding is required for proper preventative measures and treatment. Here, we investigated musculoskeletal injuries or disorders among members of the Japan Self-Defense Forces., Methods: All orthopedic patients (n = 22,340) who consulted to Japan Self-Defense Forces Hospitals were investigated for their type of injury or disorder, the injured body part, the mechanism, and the cause of injuries., Results: Thirty-nine percent of the cases were classified as traumatic injuries, and 61% were classified as non-traumatic disorders. Of the traumatic injury patients, the injured body part was the upper extremity in 32%, the trunk in 23%, and the lower extremities in 45% of the cases. The most common injured body location was the knee followed by the hand/finger and ankle. Exercise was the most common cause of injury, followed by traffic accident and military training. Contusions were the most common traumatic injuries, followed by sprains and fractures. Of non-traumatic disorders, the lower extremities were reported as the injured part in 43% of the disorders. Lumbar spine disorders were the most common non-traumatic disorders, followed by tendon and joint disorders., Conclusions: Over one-third of orthopedic cases among members of the Japan Self-Defense Forces are traumatic injuries, with the knee being the body part most commonly injured and exercise being the leading cause of injury.

Study Design: Retrospective study evaluating cranial facet joint violation (FJV) by pedicle screws., Objective: The aim of the study was to determine the incidence and risk factors of FJV following screw placement via cortical bone trajectory (CBT)., Summary of Background Data: CBT is a new minimally invasive technique for lumbar pedicle screw insertion that minimizes muscle dissection. Inserting a screw from a more caudal entry point can reduce iatrogenic damage to the cranial facet joint; however, no previous reports exist describing the incidence of FJV secondary to the CBT technique., Methods: We reviewed 202 consecutive patients who underwent lumbar pedicle screw instrumentation using CBT from October 2011 to June 2015. Postoperative CT scans were obtained to determine the degree and incidence of FJV. Clinical and imaging data were analyzed to clarify the risk factors of FJV. The detailed positions of the proximal screws were also investigated and compared between the FJV and non-FJV groups., Results: The incidence of FJV by the proximal screws was 11.8% (48/404), with no occurrence of intra-articular FJV. Multiple logistic regression analysis revealed that age >70 years, vertebral slip >10%, and adjacent facet joint degeneration (Pathria's grade 2 or 3) were independent factors significantly affecting FJV. There were statistically significant differences between the FJV and non-FJV groups in the facet-screw distance (3.2 ± 1.0 vs. 8.1 ± 2.3 mm, P < 0.01), the cranial angle (25.8 ± 6.3° vs. 29.9 ± 7.6°, P < 0.01), and the lamina-screw head distance (5.6 ± 1.6 vs. 6.4 ± 1.9 mm, P < 0.01)., Conclusion: Lumbar pedicle screw placement via CBT would reduce FJV; however, special care should be taken in patients with age >70 years, vertebral slip >10%, and facet degeneration., Level of Evidence: 3.

Little is known regarding the incidence of the shoulder instability in Japan. The aim of this study was to evaluate the incidence of traumatic shoulder instability among Japanese military cadets. A prospective cohort study was performed to capture all traumatic shoulder instability events between 2009 and 2012 among cadets in a military educational academy of the Japan Self Defense Forces. The total number of cadets in the cohort was 5,402 (average age 20.6 years). The incidence of instability events, including dislocation or subluxation, was calculated. Chronicity, demographics of participants, mechanism of injury, and athletic events were also evaluated. The incidence of traumatic dislocation was 4.1/1,000 person-years and that of subluxation was 6.1/1,000 person-years. The incidence of primary dislocation or subluxation was 5.4/1,000 person-years and that of recurrent dislocation or subluxation was 4.7/1,000 person-years. Of first dislocations or subluxations, 92% occurred during sports activities, including after-school sports activities, military training, and gym classes. In conclusion, the overall incidence of shoulder instability events among Japanese military cadets was 10.3/1,000 person-years, and was extremely high. Most shoulder instability events occurred during sports activities, and a program to prevent such injuries during sports activities is necessary for young participants., (Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.)

Objective: To compare the clinical and angiographic outcomes after implantation of drug-eluting stents (DESs) in patients with coronary artery disease (CAD) with or without prior cerebral infarction., Materials and Methods: Ninety-eight consecutive patients (130 lesions) who underwent successful coronary DES implantation were prospectively classified into two groups: those with a clinical history of symptomatic cerebral infarction (cerebral infarction group, 49 patients, 69 lesions) and those without a clinical history of symptomatic cerebral infarction (noncerebral infarction group, 49 patients, 61 lesions). The primary endpoint was defined as death, nonfatal myocardial infarction, and cerebrovascular events., Results: The Kaplan-Meier method was used to create a primary endpoint curves to determine the time-dependent cumulative primary endpoint-free rate, which were compared using the log-rank test. The incidence of primary endpoints was higher in the cerebral infarction group than in the noncerebral infarction group (p = 0.0075). The Cox proportional hazards regression model for primary endpoint identified prior cerebral infarction (p = 0.0331, hazard ratio = 2.827) and patients with peripheral artery disease (p = 0.0271, hazard ratio = 2.757) as explanatory factors., Conclusion: The results showed that clinical outcomes were poorer in patients with CAD who had prior cerebral infarctions than in those who did not have infarction.

A new method of plasma electron density measurement using interferometric phases (fractional fringes) of an optical frequency comb interferometer is proposed. Using the characteristics of the optical frequency comb laser, high density measurement can be achieved without fringe counting errors. Simulations show that the short wavelength and wide wavelength range of the laser source and low noise in interferometric phases measurements are effective to reduce ambiguity of measured density.

Previous studies based on coronary angiography or computed tomography coronary angiography have demonstrated a high prevalence of coronary stenosis in patients with cerebral infarction and no prior history of coronary artery disease (CAD). The purpose of the present study was to compare the coronary angiographic findings of patients with prior cerebral infarction with those of patients with no prior cerebral infarction. Consecutive patients (n = 126) who underwent a first coronary angiography for suspected CAD but had no prior history of CAD were classified into 2 groups, those with a clinical history of cerebral infarction (cerebral infarction group) and those without a clinical history of cerebral infarction (noncerebral infarction group). The incidences of diabetes mellitus, peripheral artery disease, coronary stenosis, and multivessel disease were significantly higher in the cerebral infarction group than in the noncerebral infarction group. Multiple logistic regression analysis relating to coronary stenosis identifi ed prior cerebral infarction (P = 0.0027, odds ratio = 4.414) and diabetes mellitus (P = 0.0446, odds ratio = 2.619) as explanatory factors. Thirty-four of 78 patients (44%) with coronary stenosis did not have angina symptoms. Multiple logistic regression analysis regarding the lack of angina symptoms identified motor dysfunction (modified Rankin scale ≥ 2) (P = 0.0028, odds ratio = 8.323) as an explanatory factor. The results of the present study suggest that compared with patients without cerebral infarction those with the disorder have a high prevalence of coronary stenosis, and indicate that the development of angina symptoms is influenced by the severity of motor dysfunction.

Because left ventricular (LV) diastolic dysfunction is frequently the earliest indicator of LV dysfunction in patients with heart failure, the estimation of LV diastolic function is very important. On the other hand, electrocardiography (ECG)-gated technetium (Tc) -99m tetrofosmin single-photon emission computed tomography (SPECT) has been reported to be a useful method for evaluation of LV function. The objective of this study was to examine the usefulness of ECG-gated Tc-99m tetrofosmin SPECT in terms of estimation of cardiac diastolic function. Consecutive 145 patients underwent an ECG-gated Tc-99m tetrofosmin SPECT to estimate systolic and diastolic LV function, and were compared with those evaluated by ultrasound echocardiography (UCG). LV end-diastolic volume, LV end-systolic volume, and LV ejection fraction values obtained by quantitative gated SPECT (QGS) showed significant positive linear correlations with those obtained by UCG. All 145 patients were classified into 3 groups according to diastolic function estimated by UCG. The first-third mean filling rate (1/3 MFR) and peak filling rate (PFR) that revealed the LV diastolic function of the group B (normal systolic function and mild diastolic dysfunction) patients (1.01 ± 0.35, 1.85 ± 0.57) were both significantly lower than those of the group A (normal systolic and diastolic function) patients (1.43 ± 0.37, 2.43 ± 0.56). The 1/3 MFR and PFR of the group C (moderate ~ severe systolic and diastolic dysfunction) patients (0.47 ± 0.34, 0.92 ± 0.62) were also significantly lower than those of the group A and B patients. QGS may be a useful method for the evaluation of cardiac systolic and diastolic function, especially in patients with normal systolic function and diastolic dysfunction.

We demonstrate the temporal contrast enhancement in a petawatt-class Ti:sapphire chirped-pulse amplification (CPA) laser system. An extra saturable absorber, introduced downstream after a low-gain optical parametric chirped-pulse amplification (OPCPA) preamplifier, has improved the temporal contrast in the system to 1.4×10(12) on the subnanosecond time scale at 70 TW power level. We have achieved 28 J of uncompressed broadband output energy with this system, indicating the potential for reaching peak powers near 600 TW.

Using a high-contrast (10(10):1) and high-intensity (10(21) W/cm(2)) laser pulse with the duration of 40 fs from an optical parametric chirped-pulse amplification/Ti:sapphire laser, a 40 MeV proton bunch is obtained, which is a record for laser pulse with energy less than 10 J. The efficiency for generation of protons with kinetic energy above 15 MeV is 0.1%.

We have developed a femtosecond high-intensity laser system that combines both Ti:sapphire chirped-pulse amplification (CPA) and optical parametric CPA (OPCPA) techniques and produces more than 30 J broadband output energy, indicating the potential for achieving peak powers in excess of 500 TW. With a cleaned high-energy seeded OPCPA preamplifier as a front end in the system, for the compressed pulse without pumping the final amplifier, we found that the temporal contrast in this system exceeds 10(10) on the subnanosecond time scales, and is near 10(12) on the nanosecond time scale prior to the peak of the main femtosecond pulse. Using diffractive optical elements for beam homogenization of a 100 J level high-energy Nd:glass green pump laser in a Ti:sapphire final amplifier, we have successfully generated broadband high-energy output with a near-perfect top-hat-like intensity distribution.

Insulin resistance (IR) is now considered to be a risk factor for coronary arterial atherosclerosis and is likely to be involved in a limited endothelium-dependent vasodilatory function in peripheral circulation. We investigated whether IR impairs endothelial vasodilator function in the noninfarcted coronary artery. In 14 nondiabetic patients (10 males, 66 +/- 6 years) who were selected from 214 patients underwent IR evaluation by glucose clamp, a Doppler flow wire was used to measure coronary flow changes (percent volume flow index, %VFI) during intracoronary administration of papaverin (10 mg) and stepwise administration of acetylcholine (Ach; 1, 3, 10 microg/ml per minute) into the non-infarcted left circumflex coronary artery. Insulin resistance was comparatively evaluated by an euglycemic hyperinsulinemic glucose clamp (M value, mg/m(2) per minute) or by a 75g-oral glucose tolerance test (120-min immunoreactive insulin; 120' IRI, pmol/l). Eight patients (57%) were defined as having IR on the basis of results obtained by both the glucose clamp method (M values <167 mg/m(2) per minute) and 120' IRI (>384 pmol/l). There was no difference between papaverin-induced %VFI increases in IR and non-IR subjects (328% +/- 43% vs. 361% +/- 87%). However, IR subjects showed significantly lower Ach-induced %VFI increases in a dose-dependent manner (P < 0.05), especially when low (1 microg/ml per minute) and moderate (3 microg/ml per minute) doses of Ach were used (165% +/- 18% or 248% +/- 29% in non-IR subjects vs. 130% +/- 20% or 183% +/- 41% in IR subjects, P < 0.001, respectively). Moreover, %VFI increase at a low dose of Ach infusion significantly correlated with M values or 120' IRI ([%VFI Ach 1 microg] = 85.9 + 0.35 [M values], r = 0.58, P = 0.038; [%VFI Ach 1 microg] = 176.8 - 0.47.[120' IRI], r = -0.57, P = 0.035). Insulin resistance limits endothelium-dependent coronary vasodilation in association with the severity of IR in non-diabetic patients.

Poor clinical outcomes for hemodialysis (HD) patients compared to non-HD patients after coronary intervention have been reported. Although coronary intervention using sirolimus-eluting stents (SESs) might be expected to reduce restenosis in HD patients, little is known about the efficacy of the SESs. The purpose of the present study was to compare the clinical and angiographic outcomes of HD patients with non-HD patients after SES implantation. The study population consisted of 170 consecutive patients (234 lesions) who had undergone successful coronary SES implantation. The patients were classified into 2 groups, an HD group (18 patients, 27 lesions) and a non-HD group (152 patients, 207 lesions). The incidence of any clinical event was significantly higher in the HD group than in the non-HD group (50.0% versus 12.5%, P < 0.0001). Target lesion revascularization was necessary in 6 patients (33.3%) in the HD group and in 7 patients (4.6%) in the non-HD group (P < 0.0001). The Cox proportional-hazards regression model on cardiac events identified HD patients (P = 0.0301, hazard ratio = 2.704) as an explanatory factor. Moreover, the Cox proportional-hazards regression model on target lesion revascularization identified HD (P = 0.0004, hazard ratio = 6.921) and in-stent re-stenosis lesion (P = 0.0293, hazard ratio = 3.323) as explanatory factors. The present study suggests that compared with non-HD patients, HD patients with coronary artery disease treated by SESs have a poorer clinical outcome.

The objective of the present prospective multicenter case-control study was to investigate the long-term clinical outcome (5 years) of primary stenting compared to primary percutaneous transluminal coronary angioplasty (PTCA) without stenting (POBA) in patients with acute myocardial infarction at 7 cardiovascular centers in Hokkaido, Japan. Forty-one patients with acute myocardial infarction treated with successful primary stenting (stent group: case) and paired with 41 matched control subjects with acute myocardial infarction treated by successful primary PTCA without stenting (POBA group: control) were analyzed. After 1 year, the stent group had a lower incidence of the combined clinical endpoint (death, rehospitalization due to congestive heart failure, nonfatal myocardial infarction, repeat angioplasty, CABG, or cerebrovascular events) compared to the POBA group (17.1% versus 39.0%, P = 0.049). After 5 years, the incidences of congestive heart failure and cardiac death were the same in both groups. However, compared to the POBA group, the stent group had a lower combined clinical endpoint (34.1% versus 61.0%, P = 0.027). The Kaplan-Meier event-free survival curves of the stent group showed a significantly lower occurrence of clinical events compared to the POBA group (P = 0.0116). Multiple logistic regression analysis of clinical events identified age > or = 69 years (P = 0.0092, odds ratio = 4.179) and stenting (P = 0.0158, odds ratio = 0.279) as explanatory factors. Compared with POBA, primary stenting for acute myocardial infarction results in a better long-term clinical outcome.

The flexibility of the Multi-Link (ML) PENTA stent with platform 0.09 to 0.12-mm-thick struts and 12% to 16% metal/artery coverage was improved to facilitate safe delivery in complex coronary lesions. The present study was designed to evaluate the clinical (9-month) and angiographic (6-month) results of the ML PENTA stent in complex coronary lesions (modified American College of Cardiology/American Heart Association lesion type B2 or C) and to determine independent factors correlated with target lesion revascularization. The study population consisted of 86 consecutive patients who had undergone successful coronary ML PENTA stent implantation for coronary artery disease from May 2003 to July 2004 in our hospital. During the follow-up period, cardiac events were documented in 21 (24.4%) of the 86 patients. Target lesion revascularization was required in 16 (18.6%) of the 86 patients. Single logistic regression analysis showed that target lesion revascularization was significantly correlated with lesion length > 2.0 cm, residual percent diameter stenosis after the procedure > 20%, and multiple stents. Multiple logistic regression analysis showed that residual percent diameter stenosis after procedure > 20% (P = 0.0125, odds ratio = 11.585) was the significant explanatory factor of target lesion revascularization. The results of the present study suggest that 9-month clinical and 6-month angiographic outcomes in patients with coronary artery disease treated using the ML PENTA stent were excellent and target lesion revascularization after coronary ML PENTA stent implantation was influenced by residual percent diameter stenosis after the procedure.

A neutron scintillation detector based on a position-sensitive photomultiplier has been developed for neutron spin echo and small angle neutron scattering measurements. This photomultiplier has good spatial resolution, less than 1 mm2. The detection efficiency of gamma ray background is very low for using a thin ZnS/6LiF scintillator. The effective area of this detector is around 60 cm2.

Cardiac systolic (left ventricular ejection fraction) and diastolic (mitral inflow velocity pattern and/or mitral deceleration time) function were reported as predictors of clinical outcome or left ventricular remodeling in patients with acute myocardial infarction (AMI). Recently, a new index (Doppler-derived index combining systolic and diastolic myocardial performance; Tei index) for combined systolic and diastolic ventricular function has been reported to be a useful and convenient method for evaluation of global ventricular function. We therefore investigated the usefulness of the Tei index by echocardiography for evaluation of infarct size and clinical outcome in patients with AMI treated by successful primary angioplasty. We analyzed 10 age-matched control subjects and 43 consecutive patients with first AMI treated by successful primary angioplasty. The Tei index of the AMI patients was significantly greater than that of the control subjects (0.630 +/- 0.106 vs 0.375 +/- 0.036, P << 0.0001). Also, the Tei index showed a significant positive correlation with peak creatine kinase values and (99m)Tc-tetrofosmin scores. Moreover, multiple logistic regression analysis showed that the Tei index >>0.70 ( P = 0.0313, odds ratio = 14.14) was the only significant explanatory factor for cardiac death or developed congestive heart failure. The Tei index combining systolic and diastolic myocardial performance reflects infarct size and might be a predictor of clinical outcome in patients with AMI treated by successful primary angioplasty.

Unlabelled: Plasma brain natriuretic peptide (BNP) level and cardiac autonomic function are closely related to prognosis in patients with heart failure. However, their correlation and incremental prognostic values in human heart failure are unclear. We sought to evaluate the correlation between BNP level and cardiac sympathetic innervation assessed by (123)I-metaiodobenzylguanidine ((123)I-MIBG) and the prognostic value of combined assessment of risk factors for mortality in patients with heart failure., Methods: After conventional examinations and measurements of plasma BNP level and heart-to-mediastinum ratio (HMR) of cardiac (123)I-MIBG activity, 158 patients with heart failure were prospectively followed with an endpoint of cardiac death for 16 mo., Results: Fifteen deaths due to pump failure and 2 sudden cardiac deaths were documented. Plasma BNP level correlated with HMR significantly but not so tightly (r = 0.330, P < 0.0001). Univariate analysis identified plasma BNP level, HMR, chronic renal dysfunction, diabetes mellitus, age, and use of nitrates as significant predictors of fatal pump failure, and multivariate Cox analysis showed that plasma BNP level was the most powerful predictor of cardiac death. Patients with both plasma BNP level of > or = 172 pg/mL and late HMR of < or =1.74 had a greater annual rate of fatal pump failure than did those without (17.5%/y vs. 0%-3.9%/y, respectively). The hazard ratio of plasma BNP level (7.2) or cardiac (123)I-MIBG activity (10.1) increased to 34.4 when both variables were used, and prevalence of fatal pump failure significantly increased from 22% to 62.5% when diabetes mellitus and chronic renal dysfunction were present with a higher plasma BNP level and low cardiac (123)I-MIBG activity., Conclusion: Plasma BNP level is a stronger predictor than other risk factors for mortality in heart failure patients and is statistically significantly, but roughly, related to cardiac sympathetic nerve innervation. Impaired cardiac sympathetic nerve innervation and the presence of diabetes mellitus and chronic renal dysfunction, however, improve risk stratification of patients with heart failure and increased plasma BNP concentration.

Results of trials using the ACS Multi-Link (ML) stent, one of the new generation stents, were similar to or slightly better than those of trials using the Palmaz-Schatz (PS) stent. The purpose of this study was to compare long-term (3-year) clinical outcomes of patients with coronary artery disease treated with the ML stent to those treated with the PS stent. The present study consisted of 52 patients who underwent successful coronary ML stent implantation (ML group) and 52 matched control patients who underwent successful coronary PS stent implantation (PS group) from October 1997 to September 1999. During follow-up periods, cardiac events occurred in 11 patients (21%) in the ML group and 14 patients (27%) in the PS group, respectively (p = NS). Angiographic restenosis rates of American College of Cardiology/American Heart Association (ACC/AHA) lesion type A or B1 were 8.3% in both groups, and ACC/AHA lesion type B2 or C were 39.3% in the ML group and 35.7% in the PS group, respectively (p = NS). In addition, angiographic restenosis rates of ACC/AHA lesion type A or B1 were significantly lower than those of lesion type B2 or C in both groups. The results of the present study suggest that 6-month angiographic and 3-year clinical outcomes in patients with coronary artery disease treated by coronary stenting with the ML stent were comparable to those with the PS stent.

An isolated single coronary artery is a rare congenital anomaly and a cause of cardiac ischemia, congestive heart failure, and sudden cardiac death. Reported here are 3 cases of single coronary artery with acute myocardial infarction in which coronary stenting was performed. Also reported are the coronary blood flow patterns of the right coronary artery arising from the single left coronary artery.

Results of trials using the ACS MULTI-LINK (ML) stent, one of the new generation stents, were similar to or slightly better than those of trials using the Palmaz-Shatz stent. The purpose of this study was to evaluate relatively long-term (2 years) clinical outcomes of patients with coronary artery disease treated with the ML stent and to determine independent factors correlated with target lesion revascularization and cardiac events. The present study consisted of 82 consecutive patients who had undergone successful coronary ML stent implantation from January 1997 to December 1999. During the follow-up period, cardiac events occurred in 16 (19.5%) patients. All patients underwent follow-up angiography and 12 (14.6%) of the 82 patients underwent target lesion revascularization. Multiple logistic regression analysis showed that aggregation of risk factors (> or = 3 risk factors) (p = 0.0274, odds ratio=5.14) and percent diameter stenosis >20% (p = 0.0395, OR = 4.586) were the significant explanatory factors of target lesion revascularization. In addition, aggregation of risk factors (> or = 3 risk factors) exhibited a tendency to correlate with cardiac events (p = 0.0528) on multiple logistic regression analysis. The results of the present study suggest that target lesion revascularization after coronary ML stent implantation was influenced by aggregation of major coronary risk factors and residual percent diameter stenosis and that long-term clinical outcome is influenced by the aggregation of risk factors.

Prospective randomized trials of coronary stenting in patients with coronary artery disease have shown a reduced incidence of cardiac events. However, little is known of the late outcome of patients treated with coronary stenting. The purpose of this study was to evaluate the relatively long-term clinical outcomes (3 to 6 years) of patients treated with successful coronary stenting. The long-term clinical outcome was studied in 101 consecutive patients (78 males and 23 females) who had undergone successful coronary stent implantation for coronary artery disease in our hospital from October 1994 to September 1997. During a follow-up period of 48.9+/-9.5 months (range, 6-73 months), cardiac events were documented in 37 patients. The rate of survival free of cardiac events was 67% at 3 years. Multiple logistic regression analysis showed that ACC/AHA lesion type and residual percent diameter stenosis greater than 20% after stenting were the significant explanatory factors of adverse cardiac events. Long-term clinical outcome in patients with coronary artery disease treated with successful coronary stenting was influenced by the ACC/AHA lesion type of stented lesion and residual percent diameter stenosis after stent implantation.

We evaluated the diagnostic accuracy of a new method for quantitative analysis of myocardial perfusion at exercise using (99m)Tc-tetrofosmin tomographic imaging. (99m)Tc-tetrofosmin imaging of an exercise-rest sequence was performed in 30 patients with coronary artery disease (CAD) and eight age-matched control subjects. The exercise-induced myocardial count increase was calculated as the relative value (per cent increase ratio, %IR) to that at rest by correcting for physical decay for (99m)Tc and injected doses and by a subtraction technique. Exercise and rest (99m)Tc-tetrofosmin images were assessed visually and quantitatively using the per cent peak count and %IR of the myocardial count at exercise. Segments with significant coronary stenosis (diameter stenosis=75% or more) showed a significantly lower %IR than did those without significant coronary stenosis in the CAD patients (37+/-19% vs 63+/-21%, P<0.05). The diagnostic efficacy of visual analysis for detecting coronary stenosis was as follows: sensitivity, 58.1% and specificity, 81.4%. When %IR=37% was used for detecting significant coronary stenosis, sensitivity and specificity increased to 74.2% and 93.2%, respectively. Furthermore, the quantitative analysis significantly (P=0.04) improved the overall diagnostic accuracy from 73.3% to 86.7% compared to that of visual assessment. Thus, augmentation of myocardial (99m)Tc-tetrofosmin uptake at exercise is blunted in the myocardium with significant coronary stenosis. The calculation of myocardial count increase at exercise relative to that at rest can improve the diagnostic value of (99m)Tc-tetrofosmin SPECT imaging and may contribute to more accurate quantification of myocardial ischaemia and impaired tracer uptake in coronary artery disease.

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is an uncommon congenital heart disease and has a high mortality rate in infancy. However, myocardial ischemia does not develop until adolescence or adulthood in about 10% of patients. Moreover, the diagnosis of ALCAPA is often difficult in cases without heart murmur or cardiac symptoms. The authors report the case of a 31-year-old man with ALCAPA. He was admitted to the hospital for evaluation of mild shortness of breath at exercise, but he had no typical chest symptoms due to myocardial ischemia or heart failure until age 31 and he had no heart murmur. Moreover, electrocardiogram did not show an old myocardial infarction or myocardial ischemia. Therefore, the authors did not suspect ALCAPA until they performed transthoracic echocardiography and exercise-stress single photon emission computed tomography (SPECT) with Tc-99m-tetrofosmin. The final diagnosis was established from the results of coronary arteriography. In the present case, a transthoracic echocardiogram showed abnormal coronary circulation, and exercise-stress SPECT revealed reversible myocardial ischemia. Transthoracic echocardiography and myocardial SPECT imaging could be a useful noninvasive tools for diagnosing the ALCAPA.

A 31-year-old man was admitted to our hospital for further evaluation of heart failure symptoms. Crow-Fukase syndrome was diagnosed on the basis of findings of polyneuropathy, hepatomegaly, monoclonal hypergammaglobulinemia, and hypertrichosis. Dipyridamole-stress thallium-201 perfusion imaging, contrast left ventriculography, and coronary angiography revealed a markedly dilated and dysfunctioning left ventricle, extensive reversible ischemia with fixed defect, and multiple coronary lesions. Histopathology of myocardial biopsy specimens demonstrated ischemia-induced myocardial necrosis. These findings suggested that ischemic cardiomyopathy, probably due to inflammatory reactions of coronary arteries in Crow-Fukase syndrome, was responsible for the heart failure symptoms and left ventricular dysfunction in this patient.

Despite the diagnostic efficacy of stress myocardial perfusion imaging, the correlation between the actual perfusion tracer activity and diseased state of a coronary artery has not been studied in detail. We estimated exercise-related perfusion augmentation in relation to disease states of a coronary artery in diabetic and non-diabetic patients by a newly developed quantitative technetium (Tc)-99m-tetrofosmin myocardial imaging technique. Tc-99m-tetrofosmin tomographic imaging with an exercise-rest protocol was performed in 26 stable coronary patients and in 8 age-matched controls. Percent increase (%IR) in myocardial count during symptom-limited submaximal exercise-stress was calculated in 16 non-infarcted polar map segments and in each coronary territory by a subtraction technique with corrections for physical decay and injected tracer doses, and the results were compared with those of angiographically quantified coronary diameter stenosis (%DS). Percent IR and peak heart rate during exercise showed a positive linear correlation both in coronary territories with significant stenosis (%DS > or = 75%) and in control or nonstenotic (%DS < 75%) territories. The regression line in stenotic regions was, however. significantly (p < 0.01) shifted downward compared to that in non-stenotic regions. Percent IR in stenotic regions showed a significant inverse correlation with %DS. Coronary stenosis of 75% or more was identified by a %IR cutoff value of 40% with 77% sensitivity, 70% specificity, and an accuracy of 72%. In coronary territories with a %DS of less than 75%, %IR in diabetic patients was significantly lower (46+/-15%) than that in nondiabetic patients (61+/-25%). Thus, blunted exercise-related augmentation of myocardial uptake of Tc-99m-tetrofosmin correlates with the severity of coronary narrowing and diabetic state.

Objective: To investigate whether coronary stenting limits myocardial injury and preserves left ventricular function., Design and Setting: Prospective multicentre case-control study of primary percutaneous transluminal coronary angioplasty (PTCA) with and without stenting, performed in seven cardiovascular centres., Subjects and Methods: 45 consecutive patients with acute myocardial infarction who were treated with successful primary stenting (Stent group) and did not have restenosis were paired with 45 matched control subjects with acute myocardial infarction treated by successful primary PTCA without stenting, also with no restenosis (POBA group)., Results: In comparison with the POBA group, the Stent group-especially those patients with a left anterior descending coronary artery lesion-had a smaller hypokinesis area (mean (SD): 15. 1 (20.0) v 34.4 (24.3) chords), reduced hypokinesis area/risk area (25.2 (31.9)% v 58.8 (40.1)%), and a larger ejection fraction (63.3 (10.2)% v 51.7 (11.7)%) evaluated by quantitative left ventriculography using the centerline method. In the Stent group, the correlation between risk area and hypokinesis area was significantly shifted downward. Multiple logistic regression analysis on infarct size limitation (hypokinesis area/risk area < 50%) identified preinfarction angina in all subjects and preinfarction angina and stenting in patients with left anterior descending coronary artery lesions as explanatory factors., Conclusions: Primary PTCA using a coronary stent is effective in preventing myocardial injury and restoring left ventricular function in patients with anterior acute myocardial infarction.

Left ventricular (LV) and right ventricular (RV) involvement in sarcoidosis must be firmly confirmed to determine patients' prognosis. We examined whether myocardial perfusion images using technetium-99m single photon emission computed tomography (SPECT) have a diagnostic benefit in the evaluation of biventricular involvement. Sixteen patients with sarcoidosis, aged 21-78 (54 +/- 12) years old, 5 males and 11 females, complicated with cardiac disease (cardiac sarcoidosis, n = 6) including tachyarrhythmias of ventricular origin (n = 5), atrioventricular block (n = 4), and congestive heart failure (NYHA > or = II, n = 1), were enrolled in this study. Myocardial SPECT using technetium-99m sestamibi or tetrofosmin was performed and semiquantitatively scored for comparison with 25 control subjects. Perfusion abnormalities were more frequently recognized in sarcoidosis (LV 5/16, 31% and RV 14/16, 88% vs. LV 0/25, 0% and RV 8/25, 32% in controls). LV involvement had a close correlation with atrioventricular block and with congestive heart failure, and multiple sites of RV involvement correlated with ventricular tachyarrhythmia of RV origin. Total number of defect segments were highest in cardiac sarcoidosis (18/30, 60% vs. 19/60, 32% in noncardiac sarcoidosis, and 11/150, 7% in controls, p = 0.0001), and semiquantitatively evaluated total LV and RV scores (ranging from 0 to 18) were higher than those of controls (15.1 +/- 1.8 vs. 11.4 +/- 3.0 in noncardiac sarcoidosis, and 9.0 +/- 5.0 in cardiac sarcoidosis) and exhibited a significant positive linear correlation with the RV ejection fraction (y = 19.8 + 1.83x, r = 0.786, p = 0.001). Biventricular SPECT using technetium-99m is clinically useful for the noninvasive evaluation of both ventricular involvements in sarcoidosis.