Technical note: the use of a physical activity monitor to estimate the eating time of cows in pasture.

Accurate eating time can be used as an index of forage dry matter intake in grazing cows. To develop a method for easily estimating the eating time of dairy cows in a pasture, 8 lactating Holstein cows were fitted with collars equipped with commercial uniaxial accelerometers; namely, the Kenz Lifecorder EX (LCEX; Suzuken Co. Ltd., Nagoya, Japan), and were allowed to graze in a pasture for 4, 8, or 20 h daily for 7 d. The LCEX device recorded the intensity of the physical activity categorized into 1 of 11 activity levels ranging among 0 (no movement), 0.5 (subtle) and from 1 to 9 (1, light; 9, vigorous intensity) every 4s during the experimental period. The activities of the animals were also video-recorded for 11h and were manually classified into 7 categories (eating, searching, ruminating, standing resting, lying resting, drinking, and walking) at 4-s intervals. According to the count distribution of the activity levels for the categorized activities, 94.4% of the counts involving eating activity ranged from activity level 1 to 7. On the other hand, most of the counts were activity level 0 or 0.5 when ruminating and resting activities were observed. No records of activity level 8 or 9 were found in any activities. When activity level 1 was used as a threshold for discriminating eating from the other activities, the lowest misclassification rate of 5.5% was observed. With a threshold of activity level 1, the eating times in pasture for cows grazing for 4, 8, and 20 h/d were 142.8, 290.6, and 438.4 min/d, respectively, and the proportions of the time spent in pasture that were made up of eating time were 0.66, 0.67, and 0.38, respectively [the proportion during daytime (8h of the 20-h grazing treatment) was 0.63 and that at nighttime (12h of the 20-h grazing treatment) was 0.23]. The use of the LCEX device allows for easy measurement of eating time and facilitates the determination of the pattern of eating activity in pasture for grazing cows.

Short communication: effect of grazing on the concentrations of total sialic acid and hexose in bovine milk.

Sialic acid, which is located at the terminal end of glycoconjugates, is believed to have important biological functions. Its concentration in bovine milk varies depending on lactation stage and season. However, it remains unclear whether dietary factors, especially fresh forage, affect the total sialic acid concentration in milk. The purpose of the present study was to investigate the effect of grazing on the concentrations of total sialic acid and hexose in bovine milk. Six healthy dairy cows were used in a crossover design (3 cows fed fresh forage and 3 cows fed grass silage) for 2 wk. Individual milk samples were collected at 2 consecutive milkings (morning and evening) at 0, 1, 3, 5, 8, 11, and 14 d of the experimental period, and 2 consecutive samples in each cow were combined on each sampling day in proportion of the morning and evening milk yields. No differences in body weight, milk yield, or milk composition were observed between the 2 groups during the experimental period. The hexose concentration in milk did not differ between these groups during the experimental period. Conversely, the total sialic acid concentration in the milk of each grazing cow significantly increased at 11 and 14 d of the experimental period compared with that at 0 d. In the grass silage group, the total sialic acid concentration at the end of the experimental period tended to be lower than that at 0 d, but the decrease was not significant. These results indicate that grazing management could have increased the concentration of sialoglycoconjugates in milk. This suggests that grazing may increase the biological function of milk because it is thought that sialic acid is significant in many ways.

Variation of major neutral oligosaccharides levels in human colostrum.

OBJECTIVES: Human colostrum is known to be important for the protection of infants against infection by pathogenic microorganisms. This protection is thought to be due, partially, to various neutral and acidic oligosaccharides that are present in colostrum and milk. However, the concentrations of each of the oligosaccharide of human colostrum have not yet been determined. The aim of this present study was to determine the concentration of each of the major neutral oligosaccharide for three consecutive days from the start of lactation. METHOD: We analyzed the level of each neutral oligosaccharide in human colostrum, for three consecutive days from the start of lactation, obtained from 12 healthy Japanese women (ranging in age from 21 to 35 years; primipara 6 and multipara 6). The ABO blood groups of the donors were determined: A, three; B, three; O, five; AB, one. The determined human milk oligosaccharides were 2'-fucosyllactose (2'-FL), 3-fucosyllactose (3-FL), lactodifucotetraose (LDFT), lacto-N-tetraose (LNT), lacto-N-neotetraose (LNnT), three lacto-N-fucopentaose (LNFP I, II and III) and two lacto-N-difucohexaose (LNFDH I and II) using high-performance liquid chromatography (HPLC) with two derivatization techniques. RESULTS: The concentrations of 2'-FL and LDFT in colostrum on day 1 were significantly higher than those on days 2 and 3 (P<0.05). An increase in LNT was observed on day 3 compared with day 1 (P<0.05). CONCLUSION: These changes in concentrations of 2'-FL, LDFT and LNT may reflect the requirements for prebiotics and anti-infection agents by human infants during early lactation.

Blastocyst production by in vitro maturation and development of porcine oocytes in defined media following intracytoplasmic sperm injection.

The present study was carried out to establish porcine defined IVP. In Experiments 1 and 2, we investigated the efficacy of additional 0.6 mM cystine and/or 100 microM cysteamine (Cys) to a defined TCM199 maturation medium with regard to the intracellular glutathione (GSH) concentration and the developmental competence of in vitro matured porcine oocytes following intracytoplasmic sperm injection (ICSI). The control medium was a modified TCM199 containing 0.05% (w/v) polyvinyl alcohol (PVA). Cys and/or cystine were added to the control medium. The control group and immature oocytes (presumptive germinal vesicle oocytes; GV) were prepared for GSH assay. In Experiment 3, the efficacy of epidermal growth factor (EGF) addition to a modified porcine zygote medium (mPZM) for in vitro culture (IVC) medium was investigated on embryonic development and the mean cell number of blastocysts following ICSI. As a positive or negative control, 0.3% BSA (mPZM-3) or 0.3% PVA (mPZM-4), respectively, was added to the base medium. The defined IVC medium was supplemented with 5 or 10 ng/ml EGF. In Experiment 1, no significant difference was found in the rates of cleavage (31.4-64.3%) and blastocyst formation (6.5-22.9%) among the treatment and control groups. The mean cell numbers per blastocyst ranged from 30 to 48 among the groups without significant differences. However, in Experiment 2, the intracellular GSH concentrations in the oocytes cultured in the medium supplemented with 100 microM Cys (9.6 pmol/oocyte) or Cys + cystine (9.9 pmol/oocyte) were significantly (p < 0.05) higher than the control (2.5 pmol/oocyte) and 0.6 mM cystine (6.5 pmol/oocyte) groups, but not different from the GV group (9.0 pmol/oocyte). The GSH concentration in the cystine group was also significantly (p < 0.05) higher than that in the control group, but not different from the GV group. In Experiment 3, the rates of cleavage and blastocyst formation and the mean cell numbers of blastocysts were not significantly different among the groups. However, the addition of 5 ng/ml EGF into the mPZM-4 resulted in a significantly (p < 0.05) higher blastocyst rate per cleaved embryo than the other two defined groups (mPZM-4 + 5 ng/ml: 48.6%, mPZM-4 and mPZM-4 +10 ng/ml: 23.4% and 23.1%, respectively). The present results indicate that the addition of Cys to a defined medium for in vitro maturation (IVM) of porcine oocytes increases intracellular GSH concentration. Further addition of cystine into the IVM medium containing 100 microM Cys is not necessary and TCM199 plus Cys (100 microM) could be used as a defined IVM medium for porcine oocytes. The addition of 5 ng/ml EGF to a defined IVC medium has enhanced subsequent development after ICSI. This study shows that porcine blastocysts can be produced by defined media throughout the steps of IVP (IVM, ICSI and IVC).

Diurnal rhythm of cerebrospinal fluid and plasma leptin levels related to feeding in non-lactating and lactating rats.

Leptin suppresses food intake and increases energy expenditure in the hypothalamus. Rats consume most of their daily food intake during the dark phase of the diurnal cycle. Lactating rats have increased food intake, but the involvement of leptin in the regulation of food intake in this physiological condition is not well understood. The present experiment was carried out to determine the circadian pattern of leptin concentrations in plasma and cerebrospinal fluid (CSF) in relation to the feeding behavior of non-lactating and lactating rats. Female rats were maintained on a controlled lighting schedule (lights on between 0600 and 1800 h) and the food intake of lactating rats was two- or threefold higher than that of non-lactating rats. In both groups, food intake was three times greater in the dark phase (P<0.01) compared with the light phase. The plasma concentrations of leptin were lower (P<0.01) in lactating rats than non-lactating rats in both light and dark phases, but there were no differences in plasma leptin levels between light and dark phases. In contrast, and in both groups, the leptin concentrations in CSF were lower (P<0.01) in the dark phase than in the light phase. Leptin levels in CSF were lower (P<0.01) in lactating rats than in non-lactating rats. We conclude that a diurnal pattern of leptin levels within the brain (but not in plasma) reflects characteristics of feeding behavior in lactating and non-lactating rats.

Circulating leptin response to feeding and exogenous infusion of insulin in sheep exposed to thermoneutral and cold environments.

Leptin has been shown to regulate feed intake and energy expenditure. Insulin stimulates leptin secretion in rodents, but its action on leptin secretion is still obscure in ruminants. If insulin stimulates leptin secretion in ruminants, circulating leptin concentrations may change during exposure to cold, because of fluctuating insulin secretion and action in the cold environment. The present experiment was designed to determine whether feeding or exogenous administration of insulin affects circulating leptin levels in sheep exposed to thermoneutral and cold environments. Suffolk rams that were shorn and fed a diet once daily were subjected to a thermoneutral (20 degrees C) or cold (0 degrees C) environment for at least 1 week. Overall mean concentrations of plasma leptin in the feeding experiment were lower (P<0.05) in the cold environment than in the thermoneutral environment. Plasma leptin levels remained relatively unchanged after feeding in both environments, though plasma insulin response to feeding in both environments increased (P<0.01). The euglycemic clamps (insulin infusion rate: 4 mUkgBW(-1)min(-1) for 2 h) increased (P<0.01) circulating leptin concentrations in the thermoneutral, but not in the cold environment. These results suggest that lower circulating leptin levels in ruminants exposed to the cold environment could be partly due to the depressed insulin action on leptin secretion.

[Review of papers on the efficacy of the treatment in sudden deafness reported between 1989 and 1998 in Japan].

We reviewed hearing recovery in 3,430 patients with sudden deafness reported between 1989 and 1998 in Japan, evaluated using standards of the Research Group on Sudden Deafness of the Ministry of Health and Welfare of Japan. Complete recovery was seen in 30.8%, marked in 24.7%, slight in 23.3% and no change in 21.8%. No remarked improvement in recovery of hearing was seen in patients with sudden deafness in these 10 years. The number of patients studied in evaluating the efficacy of therapies may thus affect results. Complete recovery from sudden deafness was nearly 30% in proportion to the increase of number of patients studied in the literature. At least 200 patients should be studied to make a reliable evaluation.

[Long-term effects of non-supervised home exercise therapy on quality of life in patients with myocardial infarction].

OBJECTIVES: Improvement in exercise tolerance is an important goal in cardiac rehabilitation, but improvement in quality of life (QOL) must also be considered. Therefore, we planned a non-supervised walking exercise program at home for 1 year in patients in the convalescent phase of myocardial infarction to study the exercise tolerance and QOL. METHODS: Thirty-two patients (mean age 60.3 +/- 10 years, 23 men and 9 women) performed our non-supervised home exercise program in which the exercise prescription was based on the rating of perceived exertion. Before discharge, 1 month and 1 year after discharge, exercise tolerance was measured by the cardiopulmonary treadmill exercise test, and QOL was investigated by questionnaire. RESULTS: Anaerobic threshold increased from 15.8 +/- 3.4 ml/kg/min before discharge to 17.5 +/- 3.0 ml/kg/min 1 month after (p < 0.05) and to 18.3 +/- 3.0 ml/min/kg 1 year after (p < 0.05 vs at discharge), and peak oxygen consumption increased from 22.2 +/- 4.3 to 25.2 +/- 5.1 ml/kg/min (p < 0.05) and to 26.4 +/- 5.2 ml/kg/min (p < 0.05 vs at discharge), respectively. QOL score by questionnaire was maintained in 13 patients (improved in 3, same in 10) and decreased in 19 of 32 patients from discharge to 1 month, and the score was maintained in 18 patients (improved in 13, same in 5) and decreased in 14 of 32 patients from 1 month to 1 year after discharge. CONCLUSIONS: In patients with myocardial infarction in the convalescent phase, our non-supervised home exercise program resulted in improvement in exercise tolerance, but QOL score decreased gradually. Therefore, we should not only prescribe an exercise program, but also must give more psychosocial support to the patients. The reasons for the decreased QOL by cardiac rehabilitation must be further investigated.

[Clinical characteristics of ventricular tachycardia and ventricular fibrillation in exercise stress testing].

OBJECTIVES: Ventricular tachycardia (VT) and ventricular fibrillation (Vf) induced in exercise stress testing should be treated urgently, although the occurrence of arrhythmia is rare. The conditions for the onset of arrhythmia and the clinical characteristics of VT and Vf patients in exercise stress testing were studied. METHODS: Fifty-nine patients (mean age 54 +/- 17 years, 41 males, 18 females) with VT (succession of 3 or more ventricular premature beats) or Vf induced in exercise stress testing were selected from 7,594 patients with consecutive treadmill stress testing in our hospital from January 1993 to February 1998. RESULTS: The incidence of exercise-induced VT or Vf was 0.8%, and there were no fatal accidents in all tests. Among the 59 patients with exercise-induced VT or Vf, 52 patients had non-sustained VT, 5 had sustained VT, and 2 had Vf. Of the 59 patients, 23 had rhythm or conduction disturbances, 14 had coronary artery disease, 13 had cardiomyopathy, and 9 had valvular heart disease. The VT or Vf incidence in coronary artery disease was 0.2%, and in valvular heart disease was 10.8%. VT or Vf occurred at over 80% of maximum heart rate exercise intensity in 40 patients, including 4 with sustained VT and 2 with Vf, of the 59 patients. Also, in 9 VT patients including the 4 sustained VT patients, VT occurred in the exercise recovery period within 2 min after the exercise. Although VT disappeared spontaneously in 52 non-sustained VT and 3 sustained VT patients, intravenous injection of lidocaine was needed in 2 sustained VT patients and direct current defibrillator was needed in 2 Vf patients. Furthermore, only one non-cardiac death was observed in the follow-up period of average 42 months. CONCLUSIONS: Our results showed clinical characteristics and incidence of VT or Vf similar to past reports. Furthermore, all sustained VT and Vf patients, who should be treated urgently, had a past history of ventricular premature beats or VT. Our data suggest that VT and Vf could occur during the recovery period, especially in patients with documented ventricular tachyarrhythmias when the stress intensity has reached the critical level in the exercise tolerance test.

Simple methods of assessing physical activity in patients with chronic heart failure.

This article reviews simple, noninvasive ways to assess physical activity in patients with chronic heart failure. Six- or 9-minute walk tests appear to be useful not only for selecting patients with relatively advanced heart failure but also as prognostic screening tests. The Master-Borg test (Master's two-step testing and 10-point Borg scale) is useful for assessing symptoms during exercise. Weekly pedometer counts show that the level of activity in patients with heart failure is dramatically less than in healthy controls. Physical activity can be determined directly by an ambulatory calorie counter that measures step scores and energy expenditure using specific accelerometers. Careful clinical interviewing regarding symptoms, together with submaximal exercise testing and use of motion sensors, are recommended as useful, simple, noninvasive alternatives for assessing physical activity in this patient population. (c)2000 by CHF, Inc.

[Acute low-tone sensorineural hearing loss].

Two-hundred forty-one patients with acute low-tone sensorineural hearing loss (ALSH) who consulted my clinic from 1987 to 1996 were retrospectively investigated. The results were as follows: (1) In 110 patients, the sum of hearing level in three low frequencies (125 Hz, 250Hz and 500Hz) was more than 100dB, and that in three high frequencies (2KHz, 4KHz and 8KHz) was less than 60dB. This audiological finding is a widely accepted criterion for the diagnosis of ALSH. One-hundred thirty-one patients did not fit this criterion. (2) The annual number of ALSH patients gradually increased during these ten years due to an increase in the number of female patients. (3) A high incidence of young females characterized these ALSH patients. (4) Of 162 patients, 64.8% and 17.9% showed complete and partial recovery of hearing, respectively. (5) The recovery rates were compared in two groups, one group consisted of patients whose sum of hearing level in the three lower frequencies was more than 100dB, and the other group was comprised of patients whose sum of hearing level in the same lower frequencies was less than 100 dB. There was no statistical difference in recovery rate between the two groups. (6) The frequency distribution of the mean of hearing level in the three lower frequencies was investigated. The mean and standard deviation was 39.1 +/- 11.8dB. By histogram, these results resembled a normal distribution. This suggests that these 241 patients has same disease entity. The pathophysiological condition of ALSH must not be various. Also, that ALSH has the peculiarity that an approximate 40 dB hearing loss may be a normal occurrence.

A simple, reliable method of assessing exercise capacity in patients with chronic heart failure.

OBJECTIVE: The accurate determination of limitations in physical activity is important in evaluating patients with heart failure and in assessing the efficacy of treatment. However, the conventional measures used to evaluate hemodynamics, functional class, and exercise capacity all have limitations. Our objective was to develop a simple method (The Master-Borg test) for evaluating the physical activity of patients with chronic heart failure using self-evaluation of the sensation of dyspnea at a constant workload. METHODS: Patients with NYHA class I (N = 20), class II (N = 20), and class III (N = 20) chronic heart failure performed a symptom-limited treadmill exercise test to determine peak VO2 and anaerobic threshold (AT). Patients subsequently performed Master's two-step test for 90 s and maximal dyspnea was self-rated using the visual analog Borg scale (the Master-Borg test). RESULTS: The mean workload in the Master-Borg test was 15.2+/-1.6 mL x min(-1) x kg(-1). A significant correlation was found between the Master-Borg score and peak VO2 (r = 0.87) or AT (r = 0.84). The reproducibility of the Master-Borg tests was represented by a correlation coefficient of 0.93. CONCLUSION: Although simple and inexpensive, the Master-Borg test accurately represents ordinary activity levels, relates the sensation of dyspnea to peak exercise tolerance, and can be completed by most patients with heart failure. Master-Borg scores correlated with peak VO2 and AT, and can differentiate among NYHA classes I, II, and III. The Master-Borg test appears to be clinically useful for evaluating the value of physical activity and exercise capacity of patients with chronic heart failure.

[Effect of cilazapril on exercise tolerance and neurohumoral factors in patients with asymptomatic chronic heart failure after myocardial infarction].

The effects of cilazapril on exercise tolerance and neurohumoral factors were investigated in old myocardial infarction (OMI) patients with asymptomatic heart failure and reduced left ventricular ejection fraction. Cilazapril (0.5 mg) was administered once daily to OMI patients (n = 20) [NYHA class I, sinus rhythm, ejection fraction by radionuclide scanning < 50% (36.8 +/- 9.1%, mean +/- SD)]. Two weeks later, five patients were excluded from the study because of cough or hypotension, and 15 patients received 1.0 mg cilazapril once daily for the next 6 weeks. Exercise tolerance, neurohumoral factors and ejection fraction were measured in OMI patients before and after administration of cilazapril. Seven age-matched healthy adults served as the controls. OMI patients had latent heart failure because their exercise tolerance values and aldosterone levels were lower and alpha-atrial natriuretic polypeptide levels were higher than those in healthy subjects. In OMI patients, 8 weeks after cilazapril administration, exercise duration increased from 545 +/- 59 to 590 +/- 74 sec (p < 0.05), anaerobic threshold from 17.5 +/- 3.2 to 20.1 +/- 2.8 ml/min/kg (p < 0.05), peak-VO2 from 23.5 +/- 4.7 to 27.1 +/- 4.4 ml/min/kg (p < 0.05), plasma renin activity from 1.34 +/- 1.13 to 5.82 +/- 5.47 ng/ml/hr (p < 0.01) and alpha-atrial natriuretic polypeptide decreased from 100.7 +/- 44.3 to 80.5 +/- 28.0 pg/ml (p < 0.05). In patients with asymptomatic left ventricular dysfunction after myocardial infarction, 8 week's cilazapril administration improved exercise tolerance and neurohumoral conditions.

[Acute myocardial infarction during sport].

Thirty patients with acute myocardial infarction which occurred during sport were investigated to identify the type of sport, prodromata, situations at the onset of disease, habit of exercise, preceding medical evaluation, coronary risk factors, and coronary angiographic findings. Infarction occurred during golf in 12 patients, bowling in 4, gateball in 4, jogging or running in 5, baseball in 2, and tennis or table tennis in 3. The majority of the patients were playing ball games. Twenty-seven patients were men (90%) and 3 were women (10%). All patients had played the same kind of sport for several years. Twenty-four patients had one or more coronary risk factors, and especially 18 patients smoked cigarettes. Nine patients had experienced anterior chest pain but only two patients had received medical evaluation. Coronary angiography was performed in 25 patients (83.3%), revealing single-vessel disease in 14, two-vessel disease in 6, three-vessel disease in 4, and disease of all left main coronary trunks in 1. The acute episode of infarction occurred mainly in spring or fall. Many patients with acute myocardial infarction occurring during sport participate in sports of low or moderate dynamic and low static exercises which are generally regarded safe. Many patients had enjoyed their sports regularly for a long time. Though many patients had coronary risk factors, only a few had received a medical check before their heart attack.

The effects of antianginal drugs on energy expenditure during exercise in normal subjects.

The respiratory quotient (RQ = VCO2/VO2) provides important information (ie, the ratio of carbohydrate to fat utilization) concerning energy expenditure. We studied the effects of various antianginal drugs on energy expenditure during steady-state aerobic exercise in 9 healthy adult men. The drugs used were propranolol (a non-selective beta-blocker), metoprolol (a beta-1 selective blocker), amosulalol (an alpha- and beta-blocker), nicardipine (a calcium antagonist) and isosorbide dinitrate. Each drug was administered for 2 weeks, followed by a 2-week washout period. VO2, VCO2 and RQ were measured with an expired gas analyzer during treadmill exercise tests before and during the administration of each drug. Two protocols of constant-load exercise were performed: Protocol 1 lasted for 10 min at a speed of 5.5 km/h and a grade of 0%, (at a level of about 30% peak VO2), while Protocol 2 lasted for 10 min at a speed of 7 km/h and a grade of 0%, (at a level of about 40% peak VO2). RQ during exercise was significantly increased and VO2 was decreased after propranolol, metoprolol and amosulalol (P < 0.05). Neither nicardipine nor isosorbide dinitrate produced significant changes in these values. These data suggest that propranolol, metoprolol and amosulalol increase the efficiency of energy expenditure during ordinary physical activity by increasing the utilization of carbohydrate and by decreasing the utilization of fat.

[Left ventricular wall motion mimicking stunned myocardium in hypertrophic obstructive cardiomyopathy with normal coronary arteries: a case report].

A 63-year-old woman was admitted to the coronary care unit of Hyogo College of Medicine because of cardiogenic shock. She previously had been hospitalized in the Gynecology Department for the treatment of recurrent uterine cancer. She had poor appetite due to chemotherapy which was given for 10 days prior to her admission. On admission, echocardiography and cardiac catheterization revealed hypertrophic obstructive cardiomyopathy and extensive left ventricular wall motion abnormalities. Coronary arteriography showed no coronary artery disease. Left ventriculography as well as echocardiography performed on the 21st post-admission day revealed that the wall motion abnormalities had completely resolved and the systolic anterior motion of the mitral valve (SAM) was no longer evident. The systolic pressure at the apex of the left ventricle was 200 mmHg on admission. The increased ventricular pressure and the simultaneous resolution of the wall motion abnormality and SAM suggest that marked obstruction of the left ventricular outflow tract is more likely to be involved in transient ventricular wall motion abnormality rather than acute myocardial ischemia. The mechanism of the SAM in the present case seemed to be related to a Venturi effect which was augmented by the decreased preload due to hypovolemia. In addition, papillary muscle contraction seemed to pull the mitral valve toward the interventricular septum during systole.

Elevated plasma beta-endorphin levels in patients with congestive heart failure.

Recent experimental studies show that the opioid system is important to the pathophysiology of cardiovascular impairment in congestive heart failure. Plasma beta-endorphin levels were measured in 37 patients with congestive heart failure and compared with those of 21 age- and gender-matched normal subjects. The relation of plasma beta-endorphin levels and cardiac function at rest and exercise capacity was assessed in 17 of the patients with dilated cardiomyopathy. Exercise capacity was determined by symptom-limited maximal treadmill exercise with expired gas analysis. Plasma beta-endorphin levels were elevated and correlated with the patients' New York Heart Association functional cardiac status (control: 14.0 +/- 4.4 pg/ml; class II: 17.9 +/- 3.6 pg/ml; class III: 28.3 +/- 8.8 pg/ml; class IV: 46.7 +/- 14.6 pg/ml, mean +/- SD). No relation was found between plasma beta-endorphin levels and left ventricular systolic performance as assessed by M-mode and Doppler echocardiography. Plasma beta-endorphin levels were negatively correlated with cardiac output determined by Doppler echocardiography and positively correlated with systemic vascular resistance (r = -0.733, r = 0.747, respectively, both p less than 0.001), but not correlated with calf blood flow as measured by a plethysmography. A good correlation was found between plasma beta-endorphin levels at rest and exercise capacity. The correlations with peak oxygen consumption, anaerobic threshold, and peak rate-pressure product were r = -0.721, -0.672, and -0.674, respectively (p less than 0.01). The data show that plasma beta-endorphin levels are elevated in patients with congestive heart failure and reflect, to some degree, the severity of the disease.

[Cardiopulmonary exercise test in patients with DDD pacemaker: report of two cases with increased exercise capacity by decreased ventricular tracking limit rate setting].

We reported 2 patients with complete A-V block with a DDD pacemaker whose exercise capacity was increased by decreased ventricular tracking limit rate setting (VTL) of their pacemakers. Cardiopulmonary exercise test was used for estimating exercise capacity. Case 1: A 15-year-old girl complained of fainting. Her electrocardiogram (ECG) revealed complete A-V block (atrial rates 100/min, ventricular rates 39/min). After implantation of a DDD pacemaker and the VTL setting at 152/min, her bradycardia disappeared, however, she complained of dyspnea after a few minutes' walk. We performed symptom-limited cardiopulmonary exercise test with a motor-driven treadmill. When the pacing rate reached VTL (152/min), ECG suddenly changed to approximately 2:1 pacing (80/min) and the patient complained of dyspnea. Concomitant rapid increases in VE, VCO2 and RQ suggested that dyspnea was caused by the marked change in pacing rates on VTL. With the lowered VTL (110/min), there was no rapid increase in VE, VCO2 and RQ, and dyspnea subsided when the pacing rate reached VTL. At the same time, the peak VO2 and exercise time were increased by 15% and 8%, respectively. Case 2: A 47-year-old man complained of syncope. His ECG revealed complete A-V block (atrial rates 100/min, ventricular rates 33/min). After a DDD pacemaker implantation (VTL: 150/min), he experienced dyspnea while walking up the stairs in his office. Like in Case 1, when the VTL was lowered from 150/min to 110/min, both the peak VO2 and exercise time were increased by 11%.(ABSTRACT TRUNCATED AT 250 WORDS)

[Exercise tolerance in patients after successful percutaneous transluminal coronary angioplasty].

In 32 patients with successful percutaneous transluminal coronary angioplasty (PTCA), we performed treadmill exercise tests (TMET) before and about one month after PTCA to assess the correlation between the improvement in coronary artery lesions and exercise tolerance. Either the Bruce protocol (B: n = 12) or the modified Bruce protocol (MB: n = 20) was used; with the latter being applied to patients whose cardiac function seemed depressed. In 15 patients, oxygen consumption (VO2) was measured by analyzing the expired gases, 13 patients underwent exercise thallium-201 myocardial perfusion scintigraphy before and after PTCA, whose results were compared with those of TMET. In both B and MB protocols, the treadmill walking time was significantly prolonged after PTCA, compared to that before PTCA (B: 7.4 +/- 1.3 vs 9.5 +/- 1.9, MB: 11.4 +/- 3.5 vs 12.7 +/- 3.5 min). Heart rates (HR) and rate pressure products (RPP) were significantly increased after PTCA in both protocols (HR B: 139 +/- 18 vs 154 +/- 17, MB: 121 +/- 20 vs 137 +/- 19 bpm, RPP B: 26,500 +/- 5,600 vs 30,300 +/- 6,700, MB: 19,400 +/- 6,200 vs 22,700 +/- 6,600 mmHg.bpm), however, systolic blood pressure did not change significantly after PTCA in either protocol. While there was a significant improvement in VO2 after PTCA (21.6 +/- 6.3 vs 25.7 +/- 4.2 ml/kg/min), the O2-pulse remained unchanged. Thallium-201 myocardial scintigraphy revealed improvement of myocardial perfusion in 8 of the 13 cases examined.(ABSTRACT TRUNCATED AT 250 WORDS)