Pericardial fat accumulation in men as a risk factor for coronary artery disease.

An increment of abdominal visceral fat accumulation has been reported to be a coronary risk factor. We determined the predictive power of pericardial fat (Pfat) accumulation as intra-thoracic visceral fat, in the diagnosis of coronary artery disease (CAD). Among 251 (181 non-obese [body mass index<25], 70 obese [body mass index> or =25]) Japanese male patients who underwent computed tomography (CT), 128 (90 non-obese, 38 obese) patients were suffering from CAD. Pfat volume was determined by the sum of cross-sectional images 1cm thick from the atrial appendage to the apex over the diaphragm. Abdominal visceral fat (Vfat) and subcutaneous fat (Sfat) areas were measured by a single scan at the L4-L5 region. Pfat was most associated with Vfat in body fat distribution. In non-obese patients, Pfat was most associated with CAD among the various risk factors including body fat distribution. Moreover, Pfat was the strongest independent variable for the severity of CAD, determined by coronary angiogram. This result showed that pericardial fat accumulation was a stronger coronary risk factor than the other body fat distributions in non-obese men.

Progression and regression of atherosclerotic findings in the descending thoracic aorta detected by enhanced computed tomography.

Reports evaluating the progression and regression of atherosclerosis by non-invasive procedure are still limited. We investigated the progression and regression of atherosclerotic intimal thickening of the descending thoracic aorta non-invasively measured by enhanced computed tomography in 83 patients (average age 51.0 years) at the beginning and end of a 2.5 year period. The patients were not taking anti-hypertensive, lipid-lowering or hypoglycemic drugs and therefore we consider them as a natural history cohort. At entry, the extent of aortic intimal thickening was 35.2% of the circumference of the cross-section of the wall, which increased to 39.7% after 2.5 years. Spontaneous progression was associated directly with age, elevated levels of total cholesterol, LDL-cholesterol, LDL/HDL cholesterol ratio, diastolic blood pressure, and inversely to HDL-cholesterol. There was little correlation with triglycerides, systolic blood pressure, fasting glucose or body mass index. In 65 of the patients, aortic atherosclerosis progressed, while in 9 patients it remained unchanged, and in a further 9 it regressed. The levels of lipid variables, apart from HDL-cholesterol, and diastolic blood pressure in the patients with spontaneous progression were significantly higher than in the unchanged and spontaneous regression. Thus, this study verified the natural history of aortic atherosclerosis non-invasively measured by enhanced CT.

Evaluation of morphological changes of the atherosclerotic aorta by enhanced computed tomography.

Enhanced and non-enhanced computed tomography (CT) were performed in 405 subjects (222 men; 183 women; mean age 57 years). Intimal atherosclerotic changes of the aorta were quantified by enhanced CT, revealing the atheromatous intima to be projecting and thick-walled, while non-enhanced CT demonstrated aortic calcification. We measured the degree of aortic intimal changes at various segments of the aorta. In 224 cases, CT was performed from the aortic root to the bifurcation of the abdominal aorta. Intimal changes were found predominantly at the aortic arch, the middle descending thoracic and the infrarenal abdominal aorta. As for the intimal changes, aortic calcification and aortic pulse wave velocity were significant atherosclerotic characteristics. The aortic diameter did not show a significant association with intimal change. Among the various atherosclerotic risk factors, intimal change was significantly associated with age, systolic blood pressure, serum total cholesterol and diabetes mellitus, whereas gender, diastolic blood pressure, relative weight and cigarette use were not significantly related. For coronary artery disease and arteriosclerosis obliterans, aortic intimal changes constituted a significant atherosclerotic feature. In cerebrovascular disease, however, aortic intimal change did not play a significant role.

Expansion rate of thoracic aortic aneurysms and influencing factors.

The risk of rupture of an aortic aneurysm increases with size and rapid expansion rate. We studied the expansion rate of thoracic aortic aneurysms and the factors influencing expansion rate, and compared the results with those of abdominal aortic aneurysms. Forty thoracic aortic aneurysms and 25 abdominal aortic aneurysms were serially examined with enhanced and nonenhanced computed tomography. The mean expansion rate of thoracic aortic aneurysms was 1.3 +/- 1.2 mm/yr and was significantly lower than 3.9 +/- 3.2 mm/yr of abdominal aortic aneurysms. The factors increasing expansion rate of thoracic aortic aneurysms were initial size of aneurysms, diastolic blood pressure, and presence of renal failure by univariate analysis. Multivariate analysis concerning the entire aortic aneurysms also revealed that the large size of the aneurysm and the presence of the aortic aneurysm in the abdomen increased expansion rate of aneurysms.

Coronary artery motion during the cardiac cycle and optimal ECG triggering for coronary artery imaging.

RATIONALE AND OBJECTIVES: Our purpose was to investigate the motion characteristics of the coronary arteries and determine optimal electrocardiographic (ECG) trigger time during the cardiac cycle to minimize motion artifacts. METHODS: Contrast-enhanced multislice movie studies of electron beam tomography (EBT) images were performed on 70 subjects. The EBT datasets, which covered an entire cardiac cycle at 58-ms intervals, were acquired for a short-axis view of the heart with ECG triggering. The pixel values along x and y axes were measured at multiple intervals during the cardiac cycle to establish the motion distance and velocity of three major coronary arteries. RESULTS: Coronary artery motion varied greatly throughout the cardiac cycle in three major coronary arteries and increased with the patient's baseline heart rate. The greatest and lowest velocities of coronary arterial movement during the cardiac cycle were determined. Based on the lowest velocity of right coronary artery movement during the cardiac cycle, the optimal ECG trigger times were located at approximately 35% (31.4%-37.6%) or 70% (68.7%-71.4%) of the R-R interval in patients whose resting heart rate was < or =70 beats per minute (bpm); at 50% (47.2%-61.1%) of the R-R interval in the 71- to 100-bpm group; and at 55% (52.8%-59.1%) of the R-R interval in the >100-bpm group. Our data demonstrated that the motion characteristics of the left circumflex artery were quite similar to those of the right coronary artery and that the left anterior descending coronary artery had no significant differences in motion throughout the cardiac cycle. A minimum scan speed of 35.4 to 75.5 ms per slice is needed to completely diminish cardiac motion artifacts (in-plane coronary artery motion with <1-mm displacement). CONCLUSIONS: For coronary artery screening, the optimal ECG trigger time should be determined according to the patient's heart rate, thus greatly reducing motion and motion artifacts during 100-ms acquisitions.

Unoperated thoracic aortic aneurysms: survival rates of the patients and determinants of prognosis.

The purpose of this study was to evaluate the long-term prognosis of unoperated thoracic aortic aneurysms, and to detect the risk factors which determine the prognosis of unoperated patients. The subjects were 52 unoperated patients with 58 thoracic aortic aneurysms (22 of the ascending aorta, 36 of the descending aorta or the aortic arch) and 38 with abdominal aortic aneurysms. The survival rates of the patients with ascending aortic aneurysms at 3 years and 5 years and those of the patients with descending aortic aneurysms at 5 years were significantly higher than those of the patients with abdominal aortic aneurysms. The risk factors for rupture of thoracic aortic aneurysms were the large size of aneurysms and non-management by the cardiologist and the risk factors for death unrelated to the aneurysms were patient age, male gender and non-management by the cardiologist.

[Amygdaloid kindling in weanling rat and rekindling upon maturization].

To understand the epileptic phenomenon in the immature brain and to investigate whether or not the epileptogenesis acquired in young age is retained after maturation, we carried out the amygdaloid kindling preparation (AM-K) on rat. Ten 3-week-old Wistar rats (3-week-old group) and ten 10-week-old rats (10-week-old group) were stimulated every 2 hours during 09:00-17:00, from five days after operation (Experiment 1). Nine kindled weanling rats (K-group) and ten weanling rats with no stimulation only electrodes implantation (non-K-group) were rekindled upon maturization (Experiment II). Stages of AM-K were classified according to the criteria of Racine. The results obtained were as follows: 1) The 3-week-old group needed significantly fewer stimulations and a shorter AD-durations during early stages (C0-2) of amygdaloid kindling, in comparison with the 10-week-old group. However, there was no significant difference between the two groups as to stimulations and AD-duration during later stages (C3-4) of the kindling. 2) The K-group were rekindled significantly fewer stimulations and a shorter AD-durations than non-K group during early stages. On the other hand, there was not significant difference between the two groups as to stimulation and AD-duration during later stages of the kindling. From the results, the following conclusions were made; The seizure susceptibility of weanling rat's limbic system is high and the epileptogenesis in the limbic system can be maintained even up to adulthood.

[Natural history and prognosis of medical treatment for the patients with aortic dissections].

The natural history of patients with acute aortic dissections in extremely poor. In 1958, Hirst et al reported 21% of such patients died within a 24 hours, 80% died within a 4 weeks and 93% died with in a 1 year if not treated aggressively. However, there has been a dramatic improvement in the prognosis of patients with aortic dissections since the introduction of surgical treatment by DeBakey et al, and that of medical treatment by Wheat et al. We studied the long-term results of medical treatment for aortic dissections and evaluated the risk factors that determine the prognosis of medically treated patients. The survival rates of medically treated patients with type A dissections at 24 hours, 1 week, 1 month, 1 year, and 10 years after the onset of the disease were 74, 41, 36, 34, 23%, respectively, and the survival rates in type B dissections were 100, 94, 92, 85, 60%, respectively. The risk factors in the acute phase of dissections were type A and serious complications. These in the chronic phase were increasing age, the large diameter of the dissecting aorta and serious complications in acute phase, excluding shock and pericardial tamponade. These results show that emergency surgical intervention is indicated in the patients with acute type A dissections and in those who had acute type B dissections with serious complications.

[CT and MRI diagnosis].

This section surveys the clinical usefulness of spiral-computed tomography (CT) and magnetic resonance imaging (MRI) in the diagnosis of thrombotic arteriovenous diseases. Spiral CT is useful to detect arterial occlusive disease by using 3D rendering, so call, "CT angiography (CTA)". 3D rendering techniques have been predominantly applied to CTA are the shaded surface display (SSD) and the maximum intensity projection (MIP). These renderings have the lacks that in an MIP no depth cues are inherent and SSD lose the majority of the scan data. The volume rendering (VR) makes up for this loss by rendering what is effectively a binary image of pixel values above the threshold. As the application of MRI in the evaluation of vascular diseases, MR angiography using time-of-flight or phase contrast techniques was performed in the past. However, according to the progress in high speed imaging method, contrast-enhanced 3D MR angiography is now used routinely and will be still more important in the diagnosis of various vascular diseases.

[Evaluation of arterial sclerosis by CT, MR imaging and MR angiography].

Wall thickening and intimal changes obtained by enhanced CT are early findings of aortic sclerosis. These findings are often detected in the lower abdominal aorta and middle thoracic descending aorta of normal subjects over 30 years of age, as predictors of atherosclerosis. Arterial calcification is a useful sign for evaluating atherosclerosis, especially, in the coronary arteries. The sensitivity and specificity of CT-detected coronary calcification in coronary stenosis by CAG were 76% and 80%, respectively, in our study. In the patients with atherosclerosis, MRI demonstrates wall thickening, intimal projection and narrowing of the lumen in the aorta and large arteries. MRA can be applied to more peripheral arteries, particularly, in the head and extremities, and will be available for screening of atherosclerotic disease in the near future.

Outcomes of pediatric ABO-incompatible kidney transplantations are equivalent to ABO-compatible controls.

BACKGROUND: Due to the profound shortage of suitable deceased allografts, much effort has been made to investigate whether successful kidney transplantation (KT) is possible across the ABO blood group barrier even for pediatric recipients. METHODS: We reviewed 52 consecutive ABO incompatible (ABOic) transplantation performed between September 1989 and March 2011. The mean age at transplantation was 10.6 ± 3.9 years (range, 4.4-19.7), with 35 boys and 17 girls. The donor-to-recipient ABO blood antigen incompatibility was as follows: A1/O (n = 17); B/O (n = 13); A1/B (n = 6); B/A1 (n = 1); A1B/B (n = 9); and A1B/A (n = 6). As a control group, data were collected from 271 pediatric ABO compatible (ABOc) living donor KT in the same period. RESULTS: Overall acute rejection episodes (ARE) among the ABOic group were significantly higher than those of the ABOc group (44% vs 26%; P < .02). However, there was no difference in glomerular filtration rate (GFR) at 1 year after transplantation: 86 ± 31 mL/min for ABOic vs 99 ± 37 mL/min for ABOic, respectively. The 1-y, 5-y, and 10-year patient survival rates were 98%, 92%, and 92% in the ABOic group, respectively, and 99%, 98%, and 97% in the ABOc group, respectively (P = not significant [NS]). The overall 1-, 5-, 10-, and 15-year graft survival rates were 94%, 88%, 86%, and 86% in the ABOic group, respectively, and 95%, 92%, 88%, and 78% in the ABOc group, respectively. CONCLUSION: ABOic KT provided long-term allograft and patient survivals equivalent to ABOc live donor transplantations.

Ultrastructural localization of alkaline phosphatase in the calcifying epithelial odontogenic tumor.

The localization of alkaline phosphatase in a calcifying epithelial odontogenic tumor obtained from a 53-year-old man was examined cytochemically. The majority of enzyme activity was associated with the epithelial cell membranes of the tumor, and faint activity was found in the cell membranes facing the adjacent stromal tissue. The reaction product of ALP was also detected in some membrane-bound vacuoles (lysosomes) and the Golgi apparatus of tumor cells. It is suggested that the appearance of enzyme activity associated mostly with the epithelial cell membrane may be related to transport function of cell membranes.

Long-term prognosis of acute aortic dissection with medical treatment: a survey of 263 unoperated patients.

Between 1973 and 1998, 263 patients with acute aortic dissection were medically treated only. They were divided into 4 groups: Stanford type A and B with open false lumen (open) or with early thrombosed false lumen (thrombosed). An event was defined as death by dissection or re-dissection. Gender, age, maximum diameter of dissected aorta and presence of shock at onset were examined as risk factors. In the open false lumen group, the presence of shock was associated with the event. During the chronic period, the diameter of the aorta was associated with prognosis in open type B dissection. The rate of event was higher in the open type A and B groups than in the thrombosed type A and B groups; however, there was no difference in the event-free rate between types A and B in patients surviving the acute period. The prognosis of medically treated dissecting aorta was not poor in patients with type B or with early thrombosed false lumen. The presence of shock at onset with open false lumen and the diameter of the aorta (> or =40 mm) in type B were significantly correlated with a poor prognosis.

[Progression to ischemic heart disease in subjects with coronary calcification as evaluated by computed tomography].

It is well known that coronary artery calcification develops in patients with advanced coronary sclerosis. Currently, it can be easily detected by computed tomography (CT). We studied the correlation of CT-detected coronary calcification with its progression to myocardial infarction, and further with the prognosis in various patients who did not have symptoms suggesting ischemic heart disease. The subjects consisted of 241 patients (136 males, 105 females) with a mean age of 61 years, categorized as a calcified coronary artery group (82 patients) and a non-calcified coronary artery group (159 patients). In all the subjects nonenhanced serial cardiac-CT scans were performed with a GECT/T 9800 for detecting coronary calcification. The mean follow-up period was four years in both groups. Among the 82 patients with coronary calcification, four developed myocardial infarction (4.9%) and 14 patients died (17%). Among the 159 patients without coronary calcification, none progressed to myocardial infarction, but 17 patients died unrelatedly (11%). Although there was no significant difference in mortality between the two groups, there was a statistical significance (p less than 0.005) as to the incidence of progression to myocardial infarction. In males, there was no significant difference (13 vs 12%) in mortality between the two groups, but the calcified group had a higher incidence of progression to myocardial infarction than that of the non-calcified group (5.5 vs 0%). In females, the calcified group had higher mortality (26 vs 8.9%) and a more frequent incidence of myocardial infarction (3.7 vs 0%) than did the non-calcified group. In conclusion, patients with coronary artery calcification are likely to develop coronary artery disease rather rapidly, even though asymptomatic. Therefore, detection of coronary calcification by non-enhanced CT is helpful for estimating the prognosis of coronary artery disease.

[Diagnostic evaluation of ischemic heart disease by X-ray computed tomography and magnetic resonance imaging].

To assess the usefulness of X-ray computed tomography (CT) and magnetic resonance imaging (MRI) in detecting and evaluating ischemic heart disease, conventional and enhanced CT were performed for 180 patients (150 with transmural infarction, 12 with subendocardial infarction, and 18 with angina pectoris). MRI examinations were performed for 38 patients (31 with transmural infarction, three with subendocardial infarction, and four with angina pectoris). With enhanced CT, two findings in the myocardium were direct evidence of myocardial infarction: 1. filling defects on the early scans, and 2. late enhancement of the myocardium on the delayed scans. The former were observed mainly at the sites of recent anterior myocardial infarction and the latter were seen in about half of the patients with recent and remote anterior myocardial infarctions. However, these findings were inadequately imaged in patients with inferoposterior infarction and subendocardial infarction. Among 137 patients with transmural infarction, enhanced CT revealed left ventricular aneurysms in 51 (37%) and ventricular thrombi in 26 (19%). ECG-gated MRI apparatus having a superconducting magnetic operating at 0.25 Tesla was used, and data for this study were collected using the single-slice spin echo technique. In eight of nine patients with acute myocardial infarction, gated MRI demonstrated the infarcted myocardium as regions of high signal intensity relative to that of the adjacent normal myocardium. Such a difference in MRI signal intensity was scarcely recognized in the chronic stage of myocardial infarction, but the indirect findings of infarction, such as regional wall thinning, wall motion disturbances, left ventricular aneurysms, and ventricular thrombi were easily detected using MRI. No characteristic finding was obtained by CT or MRI in patients with angina pectoris.

Descending aorta wall volume and coronary artery disease: a comparative study using enhanced computed tomography of the chest and coronary angiography.

The study examined the association between aortic wall volume (AWV) detected by enhanced computed tomography and coronary artery atherosclerosis observed on angiography. In 180 cases, AWV was measured as the total wall volume of a 7-cm portion of the descending thoracic aorta distal from the tracheal bifurcation. Coronary artery atherosclerosis was angiographically quantified by both Gensini score, in terms of the severity of coronary artery stenosis, and Extent score, in terms of the severity of coronary artery involvement. Mean AWV values between the patients with significant coronary artery stenosis and those without significant stenosis were 9.83+/-4.04 cm3 and 8.09+/-2.39 cm3, respectively (p<0.001). AWV was a significantly independent variable for significant coronary artery disease (p=0.0097) and an Extent score > or = 60 (p=0.0092). Calcification of AWV, however, was not associated with coronary atherosclerosis. The quantification of aortic atherosclerosis was useful for diagnosing coronary artery disease.

Assessment of aortic atherosclerosis and carotid atherosclerosis in coronary artery disease.

The present study investigated the relationship between aortic atherosclerosis and carotid atherosclerosis, and studied the effects of coronary risk factors for these arteries. The subjects consisted of 78 patients with coronary artery disease (CAD) and 69 patients without CAD. All subjects underwent enhanced computed tomography and B-mode ultrasonography within a short time period to determine the extent of aorta and carotid atherosclerosis. Significant correlations between maximal aortic wall thickness (MAWT) and aortic wall volume (AWV) with carotid intima-media thickness (IMT) were demonstrated. MAWT, AWV and IMT were significantly higher in patients with CAD compared with controls (p=0.009, p=0.024, p=0.001, respectively). Furthermore, there were significant differences in MAWT, AWV and IMT among groups classified by the number of coronary artery stenoses, and no significant differences among groups classified by risk factors, but it was shown that MAWT, AWV and IMT increased gradually as the risk factors increased in number. MAWT, AWV and IMT had positive correlations with age, systolic blood pressure and triglyceride, and a negative correlation with high density lipoprotein-cholesterol. This study demonstrated that both aortic atherosclerosis and carotid atherosclerosis are closely correlated with coronary atherosclerosis, and that the atherosclerosis indices are independently associated with age and hyperlipidemia.