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S Asakuma

Publications and source records attributed to S Asakuma.

At least 19 recordsLinked to original sources
PubMed2004

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.

Animals↗
PubMed2003

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.

Animals↗
PubMed2001

[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.

Hearing Loss, Sudden↗
PubMed2000

[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.

Anaerobic Threshold↗
PubMed2000

[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.

Aged↗
PubMed1999

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.

Aged↗
PubMed1999

[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.

Adolescent↗
PubMed1995

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.

Adrenergic beta-Antagonists↗
PubMed1995

[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.

Adult↗
PubMed1995

[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.

Aged↗
PubMed1992

[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.

Cardiac Catheterization↗
PubMed1991

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.

Echocardiography↗
PubMed1991

[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)

Adult↗
PubMed1991

[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)

Adolescent↗
PubMed1990

[Medical and surgical treatment for patients with dissecting aneurysms of the aorta].

The medical and surgical treatment of 96 patients of dissecting aneurysms was reviewed. There were 42 patients with Stanford type A dissecting aneurysms, 19 of whom received medical treatment and 23 of whom had surgical treatment. Among 54 patients with Stanford type B dissecting aneurysms, 24 had medical and 30 had surgical treatments. The treatment results and the long-term outcomes were studied using the Kaplan-Meier method, categorizing the subjects in non-survivor (in-hospital) and survivor groups. The results indicated that those with surgical treatment had a higher survival rate (75%) in the early post-operative course, for both type A and type B aneurysms. However, the long-term outcome of the survivor group was not different between type A and type B aneurysms regardless of type of treatment. Fifty-six percent of cases with type A aneurysms with serious complications survived by medical treatment alone, and no intimal tears were visualized on angiogram. Therefore, it was suggested that, in patients who had no angiographically defined intimal tears in the acute phase, medical treatment may be more effective, even for type A dissecting aneurysms.

Aortic Dissection↗
PubMed1989

[Precordial ST segment depression in acute inferior myocardial infarction: the importance of posterolateral wall infarction].

To determine whether precordial ST segment depression during acute inferior myocardial infarction indicates posterolateral wall ischemia, anatomical predominance of coronary circulation was examined by coronary angiography and evaluated in 43 patients who experienced first acute inferior myocardial infarction. Among patients who underwent intracoronary thrombolysis within six hours from the onset of symptoms, the infarct-related artery was the right coronary artery (RCA) in 35. In addition, their early 12-lead electrocardiographic features were compared with those in eight patients having the infarct-related left circumflex coronary artery (group Cx). Thirty-five patients with RCA obstruction were categorized in four groups: Four patients with left predominant type (group L), 10 with balanced type (group B), five with right super-predominant type (group SR), and 16 with right intermediate type (group RI). Seventeen of the 21 patients in groups SR and RI demonstrated precordial ST segment depression, whereas it was present in only six of the 14 patients in groups L and B (p less than 0.05). Of the 29 patients in groups SR, Cx and RI, total ST segment depression in leads V1 through V4 (sigma ST) was greater in the 14 patients in groups L and B (p less than 0.05) than in other groups. Furthermore, in these 29, all patients in groups SR and Cx had greater sigma ST than did the patients in group RI (p less than 0.05). There was no significant difference in sigma ST between groups SR and Cx. Precordial ST segment depression did not correlate with concomitant disease of the left anterior descending artery and was not a mirror image of ST segment elevation in inferior leads. On thallium-201 scintigraphy, additional perfusion defects of the posterolateral wall were present in all eight patients in group Cx and in ten of the 21 patients in groups SR and RI. Thus, precordial ST segment depression during acute inferior myocardial infarction seemed to be affected by the pattern of coronary circulation. It was concluded that this ST depression represents more extensive involvement of the posterolateral wall in patients with right predominant coronary circulation as well as in those with left circumflex artery obstruction.

Adult↗
PubMed1989

[Factors influencing exercise tolerance in patients with myocardial infarction as elucidated by Tl-201 myocardial scintigraphy].

Measurements of O2 consumption during treadmill exercise tests and Tl-201 myocardial scintigraphy were performed in 17 cases of myocardial infarction to elucidate O2 consumption at an anaerobic threshold ATVO2 as an adequate index of exercise tolerance, and the scintigraphic indices influencing the exercise tolerance. ATVO2 was obtained using the method of Wasserman and Davisand corrected by body weight. The scintigraphic indices such as the location, extent (residual myocardium), and severity (% uptake) of myocardial infarction were obtained from SPECT and bull's eye displays on Tl-201 myocardial scintigraphy. ATVO2 was correlated with theoretical VO2max as obtained by the predicted maximal heart rate (r = 0.56, p less than 0.01) and with left ventricular ejection fraction as obtained by radionuclide left ventriculography (r = 0.59, p less than 0.01). There was no significant difference between ATVO2 in cases of anterior wall infarction and those of inferior (and/or lateral wall) infarction. There was no significant correlation between % uptake and ATVO2. However, the residual myocardium showed a significant correlation with ATVO2 (r = 0.61, p less than 0.01). In conclusion, 1) ATVO2 is an adequate index of exercise tolerance and reflects cardiac function. 2) The extent of the residual myocardium is most strongly influenced by ATVO2 among the indices of myocardial damage as obtained by Tl-201 myocardial scintigraphy.

Adaptation, Physiological↗