Is the presence of interatrial septal hypertrophy a marker for atrial fibrillation in the elderly?

Interatrial septal thickness (IST) appears to increase with heart weight, body surface area, and the presence of vacuolated fat cells within the atrial septum. The increased thickness of the atrial septum is an infrequently observed but readily recognized entity by echocardiography. Several reports have suggested that some cardiac arrhythmias, particularly those of atrial origin, may be a consequence of this fatty deposition. However, to date, no study has correlated the presence of atrial fibrillation with IST in the elderly. This is of particular importance as this rhythm is so prevalent in this population. Accordingly, a retrospective analysis was conducted in a group of 40 patients, age 65 and older, to measure IST using transthoracic echocardiography. Furthermore, measurements of right and left atrial size, body surface area, left ventricular wall thickness, and left ventricular ejection fraction were recorded. Group I consisted of 20 patients with known atrial fibrillation (eight males and 12 females; mean age 78+/-8 years) and group II consisted of 20 patients in normal sinus rhythm (three males and 17 females; mean age 74+/-6 years). There was no difference between the two groups in terms of body surface area (1.83 vs. 1.79 m2; p<0.78); left ventricular wall thickness (1.16 vs. 1.12 cm; p<0.58); and left ventricular ejection fraction (48% vs. 55%; p<0.17). Group I had somewhat larger right atrial (4.2 vs. 3.4 cm; p<0.001) and left atrial (4.7 vs. 4.1 cm; p<0.02) dimensions than group II. Furthermore, IST was found to be the most significant variable that differentiated patients with atrial fibrillation from patients with normal sinus rhythm (1.39 vs. 0.85 cm; p<0.0001). Even after adjusting for all the covariables, IST remained statistically significant (p<0.0001). The findings of this pilot study show a strong correlation between IST and atrial fibrillation. Although the stimulus for the increased thickness of the atrial septum remains elusive, IST may identify a structural cause for atrial fibrillation in elderly patients that is easily identified by transthoracic echocardiography.     

Abstracts

The relationship of body fat distribution with blood pressure, fat cell weight and extracellular fluid volume was studied and compared in 20 obese hypertensive men and 20 obese hypertensive women of similar age, degree of overweight and blood pressure level. Body fat distribution, as reflected by the ratio between waist and hip circumference (W/H ratio), was significantly higher in male than in female obese patients. The W/H ratio was positively and independently correlated with systolic arterial pressure both in males and females. However, for the same W/H ratio, systolic arterial pressure was higher in females. The W/H ratio was positively correlated with gluteal fat cell weight only in males and not in females. Both in males and females, the W/H ratio was positively correlated with extracellular fluid volume, independently of the level of blood pressure level and/or the degree of obesity. The study provided evidence that the relationship between body weight and blood pressure in obese hypertensives is affected by the sex-dependence of body fat distribution with possible interferences on fat cell weight and extracellular fluid volume.

Several epidemiological studies have emphasized the positive correlation observed between body weight and blood pressure in man (1-4). Many investigations have documented the association of blood pressure with body weight, weight to height, overweight or other indices of fatness such as skinfold thickness (1-6). However, the correlation coefficients of these different relationships were found constantly small, indicating that the relationship between overweight and blood pressure is somewhat complex.

In patients with hypertension, body weight was shown to be strongly related with the levels of both blood pressure and extracellular fluid volume (7-9). On the other hand, patients with overweight and hypertension were found to be principally affected by hypertrophic obesity, as shown by the evaluation of fat cell weight (10). However these findings were exclusively observed in males. No solid data were reported in females.

The relationships between body weight and extracellular fluid on one hand, and between body weight and fat cell weight on the other hand, are certainly different in males and in females. First, in females, extracellular fluid volume is submitted to cyclic changes in sodium balance involving the effect of sex steroid hormones (1, 7, 11). Second, body fat distribution, a parameter which is weakly correlated to blood pressure (2, 11, 12), is different in males and females. In males, body fat predominates in the upper part of the body while, in females, adiposity is mainly observed in the lower part of the body (5). In that regards, it is important to investigate body fat distribution in males and females with obesity and hypertension, with reference to the most important parameters involved in body weight composition : fat cell weight and extracellular fluid volume.     

Serum proteins and nutritional status of free-living Thai elderly

Fifty-six Thai males and 146 Thai females aged 60 years and above visiting a special clinic for the elderly were investigated. The serum protein and immunoglobulin of these elderly were assessed. Anthropometric measurements were also taken. From a random sample of the group, the dietary intake of main nutrients was determined by a 24 h recall method with the help of food models. Weight, height and mid-arm muscle circumference of males were greater than those of females. Triceps skinfold thickness was less in the males than in the females. Forty-seven per cent of the individuals investigated had ₁-antitrypsin levels below 200 mg/dl and 25.4% had IgG levels of 200 mg/dl and 39% IgA levels above 450 mg/dl. The males tend to consume more calories in the form of carbohydrates than the females. The nutritional density of fat was less than 20% in the males. A negative correlation between serum albumin and height and a positive correlation between serum IgG and tricep skinfold thickness were found. Weight was found to have a positive correlation with calories, carbohydrates and fat. Height correlated positively with calories, protein and carbohydrates. Serum prealbumin correlated with fat intake. It is concluded that, except for ₁-antitrypsin, IgA, serum proteins are found in a range normally detected also in elderlies in western countries. Body composition does not relate to level of protein intake.     

The aging of the heart: weight and structural changes in the left ventricle with age]

Structural alterations of the cardiovascular system with aging are difficult to differentiate from superimposed pathologic processes. To determine whether aging "per se" affects the dimension of the heart, the weight of the heart, and the left ventricle and their rations to body weight, left ventricle wall thickness, the number of myocyte nuclei in the ventricle and the myocyte cell volume per nucleus were measured in 67 autopsies of subjects, 45 males and 22 females, who died from causes independent of cardiovascular diseases, from 17 to 90 years old. With aging, total heart weight increased slightly, while left ventricular and interventricular septum weights after dissection of the subepicardial fat decreased significantly (r = 0.44; p less than 0.001). Although left ventricular wall thickness remained constant with time, left ventricular weight to body weight ratio decreased progressively. At the structural level the number of myocyte nuclei within the left ventricle decreased (r = 0.45; p less than 0.001), whereas myocyte cell volume per nucleus increased (r = 0.30; p greater than 0.05) with age. Thus, the aging process of the heart is associated with a reduction in volume of the myocardial mass resulting from myocyte cell loss and reactive hypertrophy of the spared myocytes.     

GENDER DIFFERENCE IN THE RELATIONSHIPS AMONG HYPERLEPTINEMIA,HYPERINSULINEMIA, AND HYPERTENSION

Studies reveals that plasma leptin levels (LEP) in females are higher than those in males, and that LEP in hypertensive subjects are higher than those in BMI-matched normotensive subjects. To investigate the relationships among LEP, blood pressure (BP) and insulin sensitivity, we studied these relationships in 133 Japanese males and 263 females. LEP were positively correlated with BP, body mass index, body fat mass (FM) and homeostasis model assessment (HOMA). Regression analysis in which age and FM were adjusted showed LEP were associated with BP and HOMA. Even with adjustment by age, FM and HOMA, LEP were still positively correlated BP in males. LEP in insulin-resistant hypertensives was significantly higher than those in insulin-sensitive hypertensives, in insulin-sensitive normotensives and in insulin-resistant normotensives in males. However, in females, a significantly higher LEP was observed in insulin-resistant subjects than in insulin-sensitive subjects regardless of hypertension. These data suggest that it would be sexual difference in the relationships among hyperleptinemia, hyperinsulinemia and hypertension.     

老年人身体脂肪分布与骨密度关系的研究

目的 研究中国宁波市老年人骨密度(BMD)与年龄、体质指数(BMI)、身体脂肪(体脂)、肌肉的关系. 方法 选择宁波市老年男性61例,用双能X线吸收法测量法(DXA)测定腰椎BMD、全身BMD和体脂、肌肉分布,并与63例老年女性进行对照. 结果 老年男性腰椎BMD与年龄呈负相关(r=-0.401,P<0.01),与BMI、全身肌肉比例、躯干肌肉比例、全身脂肪比例及躯干脂肪比例呈正相关(分别为r=0.560,P<0.01;r=0.249,P<0.05;r=0.214,P>0.05;r=0.276,P<0.05;r=0.217,P<0.01);全身BMD与年龄呈负相关(r=-0.423,P<0.01),与BMI、全身肌肉比例、躯干肌肉比例、全身脂肪比例和躯干脂肪比例呈正相关(分别为r=0.542,P<0.01;r=0.314,P<0.05;r=0.197,P>0.05;r=0.253,P<0.05;r=0.191,P>0.01).老年女性腰椎BMD及全身BMD与年龄(r=0.364,P<0.01;r=0.412,P<0.01)、BMI(r=0.413,P<0.01;r=0.49,P<0.01)、全身肌肉比例(r=0.246,P<0.05;r=0.246,P<0.01)、躯干肌肉比例(r=0.215,P<0.05;r=0.320,P<0.01)、全身脂肪比例(r=0.361,P<0.01;r=0.507,P<0.01)及躯干脂肪比例(r=0.434,P<0.01;r=0.422,P<0.01)呈正相关. 结论 老年女性体脂与BMD相关性较男性更为密切;躯干脂肪与腰椎BMD呈正相关,提示向心性肥胖可能对腰椎BMD有保护作用.     

The influence of intensive physical exercise on bone acquisition in adolescent elite female and male artistic gymnasts

Physical exercise enhances bone acquisition during adolescence. The aim of the study was to evaluate the influence of intensive physical exercise on bone acquisition in adolescent elite artistic gymnasts. The study included 262 athletes (93 males and 169 females, aged 13-23 yr) participating in the 24th European Championship held in Greece. Bone age compared with chronological age was delayed by 2 yr for females (n = 120) and 1 yr for males (n = 68). For both sexes, the growth chart of bone mineral density (BMD) followed a normal pattern when estimated according to bone age rather than chronological age. For females, BMD was positively correlated with bone age, chronological age, height, body weight, body mass index, body fat, lean body mass, and with age of onset of training, and negatively with duration of exercise and intensity of training (P values range from <0.05 to <0.0001). Multiple regression analysis revealed that age of onset of training was the major parameter attenuating the effect of exercise on BMD (P < 0.001). The latter was related to the stage of puberty (P < 0.05). For males, BMD was correlated positively with bone age, height, body weight, and lean body mass (P values range from <0.01 to 0.0001). Multiple regression analysis revealed that the more powerful factor influencing BMD was weight (P < 0.01). In conclusion, bone acquisition in adolescents under intensive physical training follows the normal pattern only when estimated according to bone age. The age of onset, the duration, and the intensity of exercise attenuate the bone acquisition, at least in female artistic gymnasts.     

Echocardiographic criteria of normal left atrial size in adults

Although the measurement of left atrial diameter (LAD) is a standard part of anyechocardiographic examination, the normal range for adults has never been well established or correlated with body surface area (BSA) and sex. We studied 100 males and 100 females whose ages ranged from 15 to 70 years, with no evidence of mitral value disease or other form of heart disease which might cause left atrial enlargement. All measurements were obtained between the external surface of posterior aortic root (AR) and the internal surface of the left atrial wall and were recorded at ventricular end diastole (ED) as well as end systole (ES). The LAD at ED ranged from 9.5 to 29.5 mm with a mean of 19 mm ± 5.0 S.D.; the diameter at ES ranged from 18.3 mm to 38.7 mm with a mean of 28.5 mm ± 5.1 S.D. The mean LAD at ED was 20.7 mm ± 4.8 S.D. in males compared to the mean diameter of 18.3 ± 4.9 S.D. in females which represents a significant difference (p<0.001). The LAD did not correlate with BSA. The left atrial dimension by ultrasound in these 200 normal patients was compared with the same measurement in 50 catheterized patients with mitral valve disease and proven left atrial enlargement. When absolute values of the left atrial dimension both at end systole and end diastole were determined by ultrasound, there was a clear separation between normal and abnormal (p<0.0001).     

Contribution of fibrosis and the autonomic nervous system to atrial fibrillation electrograms in heart failure

Background- Fibrotic and autonomic remodeling in heart failure (HF) increase vulnerability to atrial fibrillation (AF). Because AF electrograms (EGMs) are thought to reflect the underlying structural substrate, we sought to (1) determine the differences in AF EGMs in normal versus HF atria and (2) assess how fibrosis and nerve-rich fat contribute to AF EGM characteristics in HF. Methods and Results- AF was induced in 20 normal dogs by vagal stimulation and in 21 HF dogs (subjected to 3 weeks of rapid ventricular pacing at 240 beats per minute). AF EGMs were analyzed for dominant frequency (DF), organization index, fractionation intervals (FIs), and Shannon entropy. In 8 HF dogs, AF EGM correlation with underlying fibrosis/fat/nerves was assessed. In HF compared with normal dogs, DF was lower and organization index/FI/Shannon entropy were greater. DF/FI were more heterogeneous in HF. Percentage fat was greater, and fibrosis and fat were more heterogeneously distributed in the posterior left atrium than in the left atrial appendage. DF/organization index correlated closely with %fibrosis. Heterogeneity of DF/FI correlated with the heterogeneity of fibrosis. Autonomic blockade caused a greater change in DF/FI/Shannon entropy in the posterior left atrium than left atrial appendage, with the decrease in Shannon entropy correlating with %fat. Conclusions- The amount and distribution of fibrosis in the HF atrium seems to contribute to slowing and increased organization of AF EGMs, whereas the nerve-rich fat in the HF posterior left atrium is positively correlated with AF EGM entropy. By allowing for improved detection of regions of dense fibrosis and high autonomic nerve density in the HF atrium, these findings may help enhance the precision and success of substrate-guided ablation for AF.     

Coronary atherosclerosis associated with body structure and obesity in 599 women aged between 15 and 50 years.

OBJECTIVE: Few data are available on the actual degree of coronary atherosclerosis or its relationship to body composition in young women. The present study was carried out to identify, with the help of simple indicators of obesity and body structure, those women under 50 y of age who have the most advanced coronary lesions. DESIGN: Autopsy reports were analysed including age, height, weight, abdominal subcutaneous fat thickness, heart weight, liver and kidney weights, coronary atherosclerosis, and ovarial status. SUBJECTS: Female cases of sudden unexpected death (n = 599) aged between 15 and 50 y autopsied in 1973-1995 were collected from the files of the Department of Forensic Medicine, University of Oulu, Finland. RESULTS: The percentage of individuals with coronary lesions was 50% in women over 41 years of age, 32% in women from 31 to 40, 17% in women from 21 to 30, and 6% in women under 20 y of age. 2.1% of the women had died from manifestations of coronary heart disease (CHD). The most severe lesions were found in women with body mass index (BMI) between 24.2 and 27.2 when adjusted for age, and when abdominal subcutaneous fat thickness exceeded 35 mm when adjusted for age and BMI. Heart weight indexed to body size increased with BMI and abdominal fat and was positively correlated with the degree of coronary atherosclerosis, which was also associated with short stature and high liver and kidney weights when adjusted for body size. CONCLUSION: Mild to moderate overweight, short stature, increased amounts of abdominal subcutaneous fat, increased components of fat free mass and myocardial hypertrophy are the physical characteristics that indicate more advanced coronary atherosclerosis in women under 50 y of age.     

Echocardiographic criteria of normal left atrial size in adults.

Although the measurement of left atrial diameter (LAD) is a standard part of any echocardiographic examination, the normal range for adults has never been well established or correlated with body surface area (BSA) and sex. We studied 100 males and 100 females whose ages ranged from 15 to 70 years, with no evidence of mitral value disease or other form of heart disease which might cause left atrial enlargement. All measurements were obtained between the external surface of posterior aortic root (AR) and the internal surface of the left atrial wall and were recorded at ventricular end diastole (ED) as well as end systole (ES). The LAD at ED ranged from 9.5 to 29.5 mm with a mean of 19 mm +/- 5.0 S.D.; the diameter at ES ranged from 18.3 mm to 38.7 mm with a mean of 28.5 mm +/- 5.1 S.D. The mean LAD at ED was 20.7 mm +/- 4.8 S.D. in makes compared to the mean diameter of 18.3 +/- 4.9 S.D. in females which represents a significant difference (p less than 0.001). The LAD did not correlate with BSA. The left atrial dimension by ultrasound in these 200 normal patients was compared with the same measurement in 50 catheterized patients with mitral valve disease and proven left atrial enlargement. When absolute values of the left atrial dimension both at end systole and end diastole were determined by ultrasound, there was a clear separation between normal and abnormal (p less than 0.001).     

老年心房颤动患者左心房内径及其电活动变化的临床研究

目的探讨老年心房颤动(房颤)患者左心房内径、电活动变化及其意义。方法142例老年非瓣膜性房颤患者(房颤组)进行彩色多普勒超声心动图仪及三导心电图仪检查,测定左心房内径(LAD)、左心室舒张期末内径、左心室后壁厚度、室间隔厚度、左心室射血分数(LVEF)及房颤的检出。采用食管调搏的方法测定左心房电生理特性,以400ms起搏周长(PCL)对左心房进行S1S2扫描,测定基础状态左心房有效不应期(LAERP);以3种不同起搏周长(400、500、600ms)对左心房进行S1S2扫描,观察LAERP频率适应性。150例健康体检者为正常对照组。结果房颤组患者LAD较正常对照组显著增加,其中左心房扩大(LAD>32mm)者占95.07%,且持续性房颤患者LAD较阵发性房颤患者显著增加。左心室肥厚患者LAD较无左心室肥厚患者显著扩大,左心房扩大与心功能降低有关,其中左心房显著扩大者(LAD≥40mm)其LVEF、每搏输出量下降最明显。房颤组患者LAERP较正常对照组显著缩短,LAERP频率适应性较正常对照组减退。结论LAD扩大及其电重构与房颤发生密切相关,LAD扩大与左心室肥厚及心功能减退有关。     

Knee isokinetic strength and body fat analysis in university students

Many factors such as anthropometric variables influence strength performance. This study is to determine the relationship between knee isokinetic strength and body composition, and to compare the gender differences. Test-retest reliability had been performed within one week for all measurement methods before the formal study. Fifty-eight 20-25 year-old university students, 32 females and 26 males, participated in this study. Isokinetic strength of the knee flexion and extension was measured at two angular velocities of 60 degrees/sec and 120 degrees/sec. Body composition was measured by bioelectrical impedance analysis (BIA) and skinfold caliper. The others variables including height, body weight, body mass index (BMI), and waist to hip ratio were measured or calculated. The results showed that the intra-class correlation coefficients for isokinetic knee strength were between 0.83 and 0.93, and body composition and anthropometric variables were between 0.83 and 0.98. Isokinetic knee strength was significantly correlated with body height, body weight, BMI, waist and hip ratio and percent of body fat estimated by skinfold caliper (r = -0.56 to 0.64). The correlation between isokinetic strength with percent of body fat estimated by BIA (r = -0.60 to -0.74; p < 0.001) and with fat free mass (r = 0.64 to 0.78; p < 0.001) was even higher. Although male subjects had significantly greater mean values in body height, body weight, waist to hip ratio and isokinetic strength than female subjects, the MANCOVA showed that the effect of gender on knee isokinetic strength would be eliminated when the covariant variable, the percent of body fat measured by BIA and BMI was controlled in the analysis model. In conclusion, knee isokinetic strength was significantly negatively correlated with proportion of fat and positively correlated with fat free mass. The magnitude of strength difference between males and females could be explained by differences in body fat proportion and BMI in this study. Therapist would take the body fat composition, fat free mass, and BMI into consideration in knee muscle strength measurement. Less body fat and higher BMI will contain more fat free mass that produces more muscle strength.     

Relations of serum aldosterone to cardiac structure: gender-related differences in the Framingham Heart Study

Aldosterone is associated with myocardial fibrosis in experimental studies and with left ventricular remodeling in heart failure patients. We hypothesized that aldosterone influences ventricular remodeling in people without congestive heart failure in the community. We examined the relations between serum aldosterone and echocardiographic left ventricular measurements in 2820 Framingham Study subjects (mean age 57 years, 58% women, 88% white) free of myocardial infarction and overt heart failure. Serum aldosterone levels were higher in women compared with men. In linear regression models (adjusted for age, systolic blood pressure, weight, height, diabetes, heart rate, hypertension treatment, and ethnicity), left ventricular wall thickness and relative wall thickness were positively related, and left ventricular diastolic dimensions were inversely related to serum aldosterone in women (P<0.05 for all), but not in men (P>0.20 for all). There was no effect modification of the relations observed in women by menopausal status. The gender-related differences in relations of serum aldosterone to relative wall thickness were consistent across subgroups defined on the basis of sex-specific median values of systolic blood pressure and body mass index. Fractional shortening, left ventricular mass, and left atrial dimensions were not related to serum aldosterone in either sex. In conclusion, in our community-based sample of individuals free of myocardial infarction and heart failure, serum aldosterone was positively associated with a left ventricular geometric pattern suggestive of concentric remodeling (increased left ventricular wall thickness and relative wall thickness but decreased internal dimensions) in women but not in men. Additional investigations are warranted to confirm these findings.     

Identification of gender differences in the thickness of the left ventricular wall by echocardiography in children

We assessed the thickness of the normal left ventricular wall according to gender by performing two-dimensional echocardiography in children. While a few studies have evaluated left ventricular wall thicknesses in children using two-dimensional echocardiography, there is little information related to the influence of gender throughout childhood. We evaluated 251 patients (128 males and 123 females) with innocent murmurs but without congenital heart anomalies, or coronary artery lesions or arrhythmias, as determined by repeated echocardiographic, and electrocardiographic examinations. Intra-ventricular septal thicknesses at end-diastole and end-systole, and left ventricular posterior thicknesses at end-diastole and end-systole were determined in the parasternal short-axis view. Significant gender differences were observed in the thickness of all four measurements. There was a linear relationship between the thickness of the left ventricular wall and height. Height was the most appropriate and practical index for assessing the thickness of the wall of the left ventricle in children.     

Leptin plasma concentrations are dependent on body fat distribution in obese patients

AIM: To evaluate whether fat distribution plays a role in determining serum leptin concentrations. PATIENTS AND METHODS: One-hundred and forty-seven obese patients, 77 males and 70 females, aged 45.1 +/- 13.2 y (mean +/- s.d.; range 21-73 y), with body mass index (BMI) ranging from 30 to 55 kg/m2 (mean 42.3 +/- 5.9). Ultrasound assessment of the thickness of subcutaneous and preperitoneal fat was carried out and calculation of their ratio as abdominal fat index (AFI), waist-hip ratio (WHR), body composition by bioelectrical impedance to evaluate the percentage of fat mass (FM%) and total amount of fat (FMKg) were also determined. Plasma leptin was measured by radio immuno assay (RIA). RESULTS: In the whole group of patients, serum leptin concentrations were 37.2 +/- 18.4 ng/ml (range 6-101.3 ng/ml); in spite of BMI values not being significantly different, women had leptin values significantly higher (47.4 +/- 17.4 ng/ml) (P < 0.01) than males (28.1 +/- 15.1 ng/ml), also after correction for fat mass. The mean thickness of abdominal subcutaneous fat was 33.7 +/- 12.9 mm and it was significantly (P < 0.001) higher in female (40.9 +/- 10.6 mm) than in male (27.1 +/- 11.2 mm) patients; preperitoneal thickness was 22.9 +/- 7.1 mm, with significantly (P < 0.05) higher values in males (24.2 +/- 6.8 mm) than in females (21.7 +/- 7.3 mm). Accordingly, AFI (in all patients 0.84 +/- 0.6) was significantly higher in males (1.09 +/- 0.6) than in females (0.56 +/- 0.2). In the overall population, leptin concentrations were directly and significantly related to subcutaneous but not preperitoneal fat; they showed a strong inverse relationship with AFI and WHR. When the results were evaluated dividing the patients according to gender, subcutaneous fat thickness showed a stronger association with leptin levels in males than in females, whereas no association was found with preperitoneal fat thickness. Leptin and AFI values were significantly related only in men. WHR values were not correlated with leptin concentrations in either sex. When fat mass was added to the model, subcutaneous fat thickness, AFI and WHR remained independently associated with leptin concentrations. Age and diabetes did not influence these measures. CONCLUSIONS: Fat distribution contributes to the variability in serum leptin in obese patients. In particular, subcutaneous abdominal fat is a determinant of leptin concentration, also independently of the amount of fat mass, whereas the contribution of preperitoneal visceral fat is not significant.     

Obesity in male and female rhesus monkeys: fat distribution, glucoregulation, and serum androgen levels

Obese (n = 8) and nonobese (n = 6) adult rhesus monkeys (Macaca mulatta) were assessed in terms of body size and distribution of body fat, glucose tolerance, and serum lipid, insulin, and androgen levels. The weights of the obese monkeys were more than 2 SD above the mean for their sex, while the nonobese monkeys averaged less than 0.25 SD from the mean. Obese males and females had excess body fat located predominantly in the abdominal region; abdominal circumference was highly correlated with total body fat, as estimated by the isotope dilution method (r = 0.98; P less than 0.001). Obese monkeys of both sexes had fasting hyperinsulinemia, greater insulin response to iv glucose administration, and marginally impaired glucose tolerance. Obese males had delayed maximal insulin response to glucose administration. Fasting serum triglycerides also were elevated in the obese monkeys (0.95 +/- 0.08 vs. 0.47 +/- 0.05 mmol/L; P less than 0.001). Obese males had lower serum dihydrotestosterone levels than nonobese males (3.1 +/- 0.7 vs. 5.6 +/- 0.4 nmol/L; P less than 0.01). Nonobese females had approximately 2-fold higher serum dehydroepiandrosterone sulfate levels than the other groups. We conclude that obese male and female rhesus monkeys have patterns of fat distribution and glucoregulatory abnormalities similar to those of humans with upper body obesity. The contribution of differences in androgen metabolism to the development of obesity and its complications in rhesus monkeys remain to be defined.     

Sympathetic Overactivity in Patients with Rheumatic Mitral Stenosis

Background: Mitral stenosis may increase sympathetic nervous activity by increasing left atrial pressure and reducing cardiac output. And elevated sympathetic nerve activity may be a risk factor for the development of clinical manifestations of mitral stenosis. In this study, we assessed the autonomic nervous system activity in patients with mitral stenosis by heart rate variability analysis and defined factors affecting autonomic functions. Methods and Results: Fifty‐four patients with rheumatic mitral stenosis were compared with an age‐ and gender‐matched control group composed of 42 healthy individuals. SDNN, RMSSD, PNN50, and HF were lower; mean heart rate (HR), LF and LF/HF ratio were higher in the patients with mitral stenosis compared to the control group. SDNN was correlated positively with left ventricle ejection fraction (LVEF), negatively with mitral valve area, left atrial (LA) diameter, and duration of symptoms. RMSSD was correlated positively with mean transmitral gradient, negatively correlated with age; PNN50 was correlated negatively with mitral valve area and positively correlated with transmitral gradient. LF was positively and HF was negatively correlated with LA diameter; LF was correlated positively, and HF was negatively correlated with duration of symptoms. LF/HF ratio was positively correlated with LA diameter and duration of symptoms, negatively with LVEF and mean valve area. Conclusion: As a result, sympathetic nervous system activity is increased in patients with mitral stenosis and sympathetic overactivity worsens their symptoms. Most significant factors that affect autonomic functions in these patients are left atrial dilatation and mitral valve area.     

The relation of antemortem characteristics to cardiovascular findings at necropsy--The Framingham Study

The relation of premorbid cardiovascular risk attributes routinely measures at regular biennial examinations to cardiac necropsy findings using a special autopsy protocol was examined among 127 decedents of the Framingham cohort. Necropsy findings analyzed were: heart weight, left ventricular (LV) muscle thickness, percent luminal insufficiency of the coronary arteries, and percent intimal involvement with atherosclerosis. Clinical data analyzed included weight, height, blood pressure and serum cholesterol measured 1, 5, and 9 years prior to death. Systolic blood pressure, but not diastolic, correlated strongly with heart weight and LV muscle thickness in both sexes, and with atherosclerotic involvement in women, but not men. Serum cholesterol 1, 5, and 9 years antemortem all correlated positively with the degree of luminal insufficiency in men, while in women only cholesterol 9 years before death correlated significantly. In multivariate analysis only systolic pressure in women correlated independently with left ventricular muscle thickness and relative weight was the only independent correlate of heart weight. Only age was an independent significant correlate of the extent of coronary atherosclerosis in women. For men, coronary atherosclerotic involvement was independently correlated with only the serum cholesterol and measures of obesity were the major predictors of heart size. The degree of coronary pathology also correlated positively with heart weight in men and LV muscle thickness in women. In general clinical data measured just prior to death did not correlate as well with pathological findings as did earlier measurements.