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The present study was conducted to investigate the effects of cilazapril on exercise tolerance and the hormone kinetics of catecholamines, the reninangiotensin-aldosterone system and alpha-atrial natriuretic peptide (ANP) in patients in the chronic phase of acute myocardial infarction (AMI). The subjects consisted of 19 cases of AMI. Cardiopulmonary exercise testing was performed 1 month after the onset of AMI, and patients were randomly assigned to either a group treated with 1 mg/day of cilazapril (9 cases) and or an untreated group (10 cases). After the completion of 2 months of exercise training at the anaerobic threshold (AT), blood samples were taken during a cardiopulmonary exercise test and various hormones were measured. In comparing the parameters of exercise tolerance before and after the completion of exercise training there were no significant differences between the 2 groups with respect to oxygen uptake, oxygen pulse, or exercise time at AT or at peak exercise. With regard to temporal changes in exercise tolerance, oxygen uptake, oxygen pulse and exercise time all tended to increase in both groups. With regard to hormone kinetics, the alpha-ANP concentration at peak exercise was significantly lower, and the noradrenaline secretions also tended to be lower, in the cilazapril-treated group, even though the peak exercise time was similar in both groups. These results may be support the hypothesis that cilazapril mitigates the left ventricular load during exercise therapy in patients in the chronic phase of AMI.

The relationship between ischemic ST depression and oxygen uptake kinetics was examined during cardiopulmonary exercise test using the ramp protocol in 22 patients (17 males and 5 females, mean age 61.4 +/- 8.1 years) with ischemic ST change (horizontal or down sloping ST depression over 1 mm) during a previous multi-stage exercise test (Bruce method). Patients were classified into three groups according to coronary angiographic findings: absence of significant stenosis group (control, n = 7), single-vessel disease group (n = 7) and multivessel disease (MVD) group (n = 8). Peak exercise time, peak heart rate, peak systolic blood pressure, anaerobic threshold, peak oxygen uptake (peak Vo2), exercise time, heart rate, systolic blood pressure, and oxygen uptake at appearance of ischemic ST change were measured. The ratio of oxygen uptake increase at appearance of ischemic ST change was calculated. Peak Vo2 was lower in the MVD group than in the control group (20.9 +/- 6.2 vs 27.3 +/- 3.3 ml/min/kg, p < 0.05), and exercise time from the beginning of ramp exercise to the appearance of ischemic ST depression was shorter in the MVD group than in the control group (5.2 +/- 2.1 vs 8.2 +/- 1.9 ml/min/kg, p < 0.05). The ratio of oxygen uptake increase was smaller in the MVD group than in the control group (0.7 +/- 0.3 vs 1.2 +/- 0.2, p < 0.01). These results could be caused by impaired increase of cardiac output due to myocardial ischemia occurring during exercise. In the clinical setting, these phenomena could be used as a parameter for differentiating ischemic from non-ischemic ST depression or evaluating the sensitivity of ischemic heart disease.

The effect of combined aerobic and weight training on indexes of muscle strength and exercise capacity was investigated in 59 patients after myocardial infarction. Subjects were randomly assigned into three groups: group I performing combined aerobic and weight training (n = 22), group II performing ordinary aerobic training alone (n = 19) and group III not performing physical training (n = 18). Before and after the training, isokinetic knee extension strength was measured and cardiopulmonary exercise testing was performed. Physical training was prescribed for 8 weeks. Weight training of knee extensors was performed at 60% of 1 repetition maximum and aerobic training was prescribed at the heart rate of anaerobic threshold (AT) level. After 8 weeks, the increase of isokinetic knee extension strength was significantly greater in group I (26 +/- 14%) than group II (6 +/- 8%) and III (4 +/- 8%). Increases in peak VO2, exercise time, AT and peak O2 pulse were greater in groups I and II than group III. Furthermore, increase of exercise time was greater in group I (25 +/- 14%) than group II (16 +/- 9%). The rating of perceived exertion in submaximal exercise decreased significantly only for group I. In patients with myocardial infarction, combined aerobic and weight training is a more effective method for increasing muscle strength and exercise capacity than only ordinary aerobic training.

Exercise training usually involves the sustained performance of exercise at a prescribed intensity. The effects of exercise performed at the anaerobic threshold (AT) have been widely studied. The effects of single-level exercise on catecholamines and cardiac function were assessed at the AT, and at 120% of the AT in eight healthy Japanese men (mean age 21.9 +/- 1.8 years). 1) Symptom-limited exercise testing utilized the ramp protocol with a bicycle ergometer (20 watts/min) for measuring AT and peak oxygen uptake (peak VO2). 2) Exercise testing was repeated on another day, following the same protocol, with blood sampled to measure norepinephrine (NE) and epinephrine (E) in the resting control state and at the AT and peak exercise. 3) Single-level exercise testing at the AT and at 120% of AT utilized the bicycle ergometer on yet another day. Blood for measurement of NE and E was drawn at 3 and 7 min after achieving a steady-state condition. In addition, the cardiac index (CI) and stroke index (SI) were measured by the CO2 rebreathing method. (1) Mean AT and peak VO2 were 18.3 +/- 1.3 and 40.2 +/- 3.0 ml/min/g, respectively. (2) NE and E measured during ramp exercise testing increased rapidly when the intensity of exercise exceeded the AT. NE measured after 3 and 7 min at the AT during single-level exercise equalled 94.7% and 94.5% of the NE value measured at the AT of ramp exercise, respectively. NE measured after 3 and 7 min at 120% of the AT during single-level exercise was 124.7% and 144.7% at the AT of ramp exercise, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

To predict exercise tolerance in the chronic phase of myocardial infarction (MI), cardiopulmonary exercise testing was performed using a ramp treadmill protocol in 25 patients at 1 and 3 months after the onset of MI. Oxygen uptake, heart rate and O2 pulse were estimated at rest, during a warm-up period, and at the levels of anaerobic threshold (AT), respiratory compensation (RC) and peak exercise. Results were as follows: 1) AT and peak oxygen uptake at 3 months after the onset of MI were 14.1 +/- 2.8 and 21.8 +/- 5.2 ml/min/Kg, respectively. 2) The subjects were divided into 2 groups according to peak oxygen uptake at 3 months: one showing peak oxygen uptake > 22 ml/min/Kg and the other < 22 ml/min/Kg. The former group (n = 13) was referred to as the good tolerance group, and the latter group (n = 12) was referred to as the poor tolerance group. Oxygen uptake at AT, RC and peak exercise was lower in the poor tolerance group than in the good tolerance group (11.2 vs 14.7, 15.1 vs 20.4, 17.1 vs 23.4 ml/min/Kg, respectively). 3) The increases in oxygen uptake from AT to RC and from AT to peak exercise were less in the poor tolerance group than in the good tolerance group. 4) O2 pulse at rest, warm-up, AT, RC and peak exercise were also lower in the poor tolerance group.2+ tolerance in the chronic phase of MI.