Michiko Yano

A Case of Reversible Posterior Leukoencephalopathy Syndrome Caused by Transient Hypercoagulable State Induced by Infection

We report a normotensive case of reversible posterior leukoencephalopathy syndrome caused by transient hypercoagulable state. Hypertension is the main risk factor for reversible posterior leukoencephalopathy syndrome, which is believed to occur as a result of high blood pressure-related dysfunction of cerebrovascular endothelial cells, because it commonly appears in hypertensive emergency. However, in this completely normotensive case, the typical clinical findings of reversible posterior leukoencephalopathy syndrome were triggered by transient hypercoagulable state without any blood pressure variation. The case was successfully treated with anticoagulation therapy using heparin. Thus, this case indicates that reversible posterior leukoencephalopathy syndrome is induced by cerebrovascular endothelial dysfunction, which is induced not only by high blood pressure but also hemostatic dysfunction.

Heterogeneity of renal cortical circulation in hypertension assessed by dynamic computed tomography

The aim of this study was to assess the grade of heterogeneous disturbance in the renal cortical circulation using dynamic computed tomography and to investigate the relationship between the heterogeneity of renal cortical circulation and hypertension. We studied 125 patients who underwent dynamic computed tomography (CT) for various abdominal diseases and had no serious hemodynamic abnormalities. In dynamic computed tomography under appropriate conditions, each pixel (image element), less than 1 mm2, has a CT number that is in proportion to the concentration of contrast media, which reflects the blood volume in the pixel. The image was constructed at the hilus level about 50 s after the start of a continuous infusion of contrast medium. The mean and standard deviation were calculated from the CT numbers in the renal cortex. The coefficient of variation, ie, the standard deviation divided by the mean value, was used as the index of the heterogeneity of renal cortical circulation. The coefficient of variation was significantly (P < .001) greater in the hypertensive patients (n = 48, 0.174 +/- 0.006 [mean +/- SE]) than in normotensive subjects (n = 77, 0.140 +/- 0.004). The coefficient increased in parallel with the patients age and with the grade of renal surface irregularity. In the patients whose serum creatinine levels were normal, this parameter also had a significant relationship (r = 0.367, P < .0001) with serum creatinine. These results suggest that the heterogeneity of renal cortical circulation is increased in hypertension and is also associated with aging. This parameter may become a sensitive indicator to detect slight deterioration in the renal cortical circulation.

Echocardiography of a right atrial mass in hepatocellular carcinoma.

SummaryAntemortem diagnosis of hepatocellular carcinoma with a tumor thrombus extending into the right atrium has been rarely observed. Although echocardiography allows easy detection of the intracardiac mass, reports of echocardiographic descriptions of a right atrial mass associated with hepatocellular carcinoma are few. Herein, we describe two cases of hepatocellular carcinoma with a tumor thrombus in the right atrium detected by transthoracic echocardiography. In one of the patients we also performed transesophageal echocardiography. Neither patient had cardiac symptoms or signs. Thus, echocardiographic examination is very important in patients with hepatocellular carcinoma, with or without cardiac symptoms and signs.

Highly Damage-Resistant Reflectors for 248 nm Formed by Fluorides Multilayers

we investigated the laser damage thresholds and optical performances of fluorides multi-layered reflectors, consisting of middle index fluoride and Na3AlF, for high power KrF laser applications. It was found the damage thresholds of those reflectors are significantly improved by laser annealing. Those reflectors with annealing resisted against the fluence of 18-27 J/cm2 (this fluence varies on combinations of various fluorides) for 248 n, 15 nsec, 10Hz pulses.

Coronary vasoreactivity to ergonovine after angioplasty: difference between the infarct-related coronary artery and the noninfarct-related coronary artery.

Background: The vasoreactivity after direct percutaneous transluminal coronary angioplasty (PTCA) in patients with previous myocardial infarction remains unknown. We examined the constrictor response to ergonovine of the infarct‐related coronary artery in comparison with that of noninfarct‐related coronary artery after angioplasty. Methods: Ergonovine was administered intravenously to 17 patients with previous myocardial infarction (group I) and to 21 patients with stable angina (group II) 1 year after PTCA. The effects of ergonovine on lumen diameter were analysed quantitatively at the PTCA segment, nonPTCA segment (proximal to the PTCA segment), and nonPTCA artery. Results: The ergonovine‐induced decrease in minimal lumen diameter at the PTCA segment was significant in group I (decrease from 2.12 ± 0.56 to 1.39 ± 0.74 mm, P<0.01), but not in group II (decrease from 1.60 ± 0.35 to 1.43 ± 0.33 mm, NS). Patients in group I showed a constrictor response at the nonPTCA artery (decrease in diameter from 2.54 ± 0.90 to 1.94 ± 0.77 mm, P<0.01), and a tendency to constrict at the nonPTCA segment (2.56 ± 0.67 to 2.11 ± 0.66 mm, P=0.06), whereas those in group II showed no significant constrictor response to ergonovine at any of the three segments examined. The changes in diameter at the three segments in patients in group I were significantly greater than those in group II (all P<0.01). Subtotal coronary spasm at the PTCA segment was provoked only in three patients in group I (18%). Conclusions: The constrictor response to ergonovine of the infarct‐related coronary artery was enhanced compared with that of the noninfarct‐related coronary artery. This difference in coronary vasoreactivity at the angioplasty segment may be due to previous hypersensitivity of the smooth muscle. Coronary Artery Dis 9:105‐111 1998 Lippincott‐Raven Publishers.

Peristent tissue proliferation of multilink stents is dependent on preprocedural plaque area: a serial intravascular ultrasound analysis.

It is not known whether any factors are related to tissue proliferation within and surrounding stents in humans. The authors used serial intravascular ultrasound (IVUS) to evaluate the relationship between IVUS parameters and tissue proliferation within and surrounding Multilink stents. They were able to analyze preinterventional and postinterventional and follow-up IVUS studies in 33 native vessel lesions in 33 patients with stable angina pectoris. Quantitative coronary angiography and IVUS measurements were performed before and after intervention and at follow-up. IVUS imaging using an automatic transducer pullback device allowed follow- up analysis of the same lesion site. The vessel area at the lesion site increased from 17.1 ±4.5 mm2 after intervention to 18.5 ±5.9 mm2 at follow-up (p < 0.01). The in-stent tissue growth (after intervention to follow-up) in-stent plaque area (PA) was 1.6 ±1.1 mm2, and the peristent tissue growth (after intervention to follow-up) peristent PA was 0.8 ±2.3 mm2. In multivariate analysis, the preprocedural PA at the lesion site was the best predictor of the peristent tissue growth, whereas no factors predicted the in-stent tissue growth. Risk factors, clinical charac teristics, and quantitative coronary angiographic parameters showed no relation to the peristent tissue growth or the in-stent tissue growth. The peristent tissue growth was closely related to the preprocedural plaque size, while the factors that affect the in-stent tissue growth were not identified.

Relation between stent expansion and arterial remodeling: A serial intravascular ultrasound study

Previous studies suggested that stent area (SA) did not change after the Palmaz‐Schatz stent implantation. Whether these findings apply to other types of stent, however, is unknown. This study assessed vascular response to stent implantation using intravascular ultrasound (IVUS) studies. Serial (pre‐intervention to follow‐up) IVUS imagings were used to study 57 native coronary lesions after the GFX stent or the Multilink stent implantation. The vessel area (VA) at lesion site increased at follow‐up (16.92 ± 3.67 mm2 after intervention to 18.17 ± 4.66 mm2 at follow‐up, P < 0.01). The SA also increased from 8.39 ± 1.90 mm2 after intervention to 8.80 ± 2.08 mm2 at follow‐up (P = 0.02). Thirty‐two percent of lesions showed late stent expansion. The stent expansion [Δ (after intervention to follow‐up) SA] correlated significantly with the VA growth [Δ (after intervention to follow‐up) VA] (r = 0.59, P < 0.0001). In conclusion, some lesions reveal late stent expansion after both the GFX stent and the Multilink stent implantation. Adaptive vessel remodeling may be followed by stent expansion. Cathet. Cardiovasc. Intervent. 50:282–289, 2000.

Light scattering of highest damage resistant fluoride HR coating for KrF laser

Fluoride HR coatings consisting of middle and low refractive index fluorides often show a higher damage threshold than oxide coatings in the UV range. However, the light scattering level of fluoride HR coatings tend to be higher than oxide ones. In this study, the scattering and surface roughness of fluoride HR coatings for KrF laser were investigated, and also compared with those of oxide HR coatings using Al2O3 as high index materials.

Long-term follow-up of primary stenting with coil stent in acute myocardial infarction

The authors evaluated clinical and angiographic outcomes for 1 year after primary stenting using coil stent for acute myocardial infarction. Twenty-eight patients underwent primary stenting with coil stent. Follow-up coronary arteriography at 3 months and 1 year was planned in all patients. Procedural success was achieved in 96%. There was no acute or subacute thrombosis. Minimal lumen diameter (MLD) was increased from 0.08 ±0.19 to 2.73 ±0.49 mm after stenting. MLD had decreased significantly for 3 months (MLD at 3 months: 2.03 ±0.86 mm, p = 0.001). On the other hand, MLD did not differ between 3-month; and 1-year follow-up (MLD at 1 year: 2.26 ±0.73 mm, p = NS). Only one patient manifested reocclusion at 3-month follow-up. The cumulative restenosis rate and target lesion revascularization rate at 1-year follow-up were 25.9% (7/27) and 11.1% (3/27). Primary stenting using coil stent is safe and feasible in patients with acute myocardial infarction and may improve clinical outcome and decrease restenosis and target lesion revascularization rate.

Benefit of intravascular ultrasound in Wiktor stent implantation.

The goal of this study was to evaluate retrospectively the efficacy and safety of intravascular ultrasound (IVUS) during Wiktor stent implantation. Until 1996, the success of stent implantation was assessed by angiographic criteria only, but in 1997, the procedure was expanded to include pre‐ and postprocedural IVUS imaging. Sixty‐six patients were included, 28 treated in 1996 (group A) and 38 treated in 1997 (group B). Stent size was larger in group B than in group A (3.6 ± 0.4 vs. 3.1 ± 0.2, P < 0.001). Acute gain was greater in group B than in group A (2.58 ± 0.61 vs. 2.11 ± 0.56, P < 0.001). Restenosis rate was 31% in group A and 14% in group B. No major acute complications due to IVUS examination occurred. IVUS is helpful in choosing optimal stent size. Cathet. Cardiovasc. Intervent. 47:28–35, 1999.