The characteristics of the left and the right heart volume in isolated ventricular septal defect were investigated in 62 patients before surgery and in 17 after corrective surgery, which was undergone at ages ranging from 0.5 to 13. Postoperative cardiac catheterization was performed one to two months after surgery. Preoperatively, the right atrial maximal volume increased in accordance with the pulmonary to systemic pressure ratio, and the left ventricular end-diastolic volume, the left atrial maximal volume and the right ventricular end-diastolic volume increased in accordance with the degree of the left-to-right syunt. These volumes decreased considerably after surgery, although they still remained above normal. The left ventricular mass also increased in accordance with the degree of the left-to-right syunt preoperatively and did not decrease postoperatively. The left and the right ventricular ejection fractions were close to or within normal limits preoperatively and remained so after surgery. On the basis of our results and the findings previously published in the literature, factors which may influence the post-operative cardiac function in ventricular septal defects were discussed.

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Ten patients with aortic regurgitation underwent aortic valve replacement using a Bjork-Shiley valve prosthesis. They ranged from 27 to 58 years of age. The studies were centered around the postoperative hemodynamics, especially concerning the function of the left ventricle during a follow-up period which averaged about 8 months. The left ventricular end-diastolic volume (LVEDV) returned to the normal range, and the muscle mass of the left ventricle decreased remarkably after surgery. The ejection fraction and mean velocity of the circumferential fiber shortening both increased up to the normal range. The left ventricular end-diastolic pressure exhibited normal values with a decrease of LVEDV. The depressed left ventricular function was largely reversible after surgery.

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The severity of aortic regurgitation (AR) is usually evaluated using cineaortography, but this procedure cannot be carried out easily because of its invasive nature. For estimating the severity of AR non-invasively as well as quantitatively, we measured the blood flow in the aortic arch using an ultrasonic pulsed Doppler flowmeter (UPDF) from a suprasternal notch. The rugurgitant ratio was calculated from the waves of relative flow volume and compared with the severity determined cineaortographically. The following results were obtained : 1) Reproducible waves of the aortic arch flow were recorded in all normal subjects and also in 19 out of 23 patients with AR. 2) Distinctive waves of the regurgitant flow, which could not be seen in normal subjects, were recorded in AR except for some mild cases. 3) The regurgitant ratio obtained from the UPDF corresponded well with the severity based on the cineaortgram. It may be concluded that the UPDF is clinically useful and reliable for quantifying AR non-invasively.

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In order to clarify the pathogenesis of alcoholic cardiomyopathy, acetaldehyde (Ach) was administered to rats using the inhalation method. Serum enzyme changes and structural alterations of the heart were observed at various time intervals after 2 ml of Ach exposure for 2 hours. Possible myocardium-related enzymes, such as glutamic oxaloacetic transaminase, lactic dehydrogenase and creatine phosphokinase, were elevated within 24 hours and then returned almost to the previous levels. The most significant change seen using light microscopy was a prominent contraction band scattered throughout the specimen in the groups exposed for 12 and 24 hours, respectively. Ultrastructually, mitochondrial swelling and cristal disarray concomitant with myofibrillar change (swelling of Z-band) were observed. The former was seen most prominently immediately after exposure, while the latter was observed 24 hours after exposure. The significance of these findings and the difference between alcoholic cardiomyopathy and ischemic lesions were discussed.

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We examined electrophysiological properties of the ischemic myocardium of the canine heart. Multiple bipolar electrodes for stimulation or for recording electrograms were placed on the epicardial surface and at the endocaridum of the ventricle. The time course of changes in excitability threshold, in effective refractory period and in local conduction time during ischemia was estimated at the epicardial and endocardial sides of the central ischemic zone, at the epicardial side of the peripheral ischemic zone and at both sides of the normal zone. Soon after left anterior descending coronary artery occlusion, a rise of excitability threshold, a lengthening of effective refractory period and a prolongation of conduction time consistently occurred in all portions of the ischemic zone. The degree of changes, however, was not uniform : it was greater at the epicardial side of the central ischemic zone. In most experiments, the changes reached maximum within 10 min after occlusion. Then, altered electrophysiological properties recovered to some extent or stabilized. The results indicate that electrophysiological properties deteriorate momentarily after coronary occlusion but then recover or stabilize, and that their changes during acute ischemia are not uniform in the ischemic region but severer at the central zone and epicardial side.

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A case of rheumatoid arthritis with an involvement of the cardiac conduction system was described. The patient was a 65-year-old man who had a 15-year history of classical rheumatoid arthritis combined with an advanced atrioventricular (AV) block resulting in Adams-Stokes seizure. Prior to the occurrence of the AV block, a complete right bundle branch block with a left axis deviation and a first-degree AV block were found on an electrocardiogram (ECG). The histological examination of the conduction system according to the serial sectioning method disclosed that the branching portion of the Hid bundle and anterior fascicle of the left bundle branch were replaced by the scarring tissue and that the penetrating portion of the His bundle, the AV node and the right bundle branch had rheumatoid granulomatous lesions. The extent and localization of the lesions in the conduction system were well correlated with the findings on the ECG.

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This study was conducted to investigate the functional capacity in post-myocardial infarction. Eighty-four multistage treadmill exercise tests were performed on 60 patients, none of whom had had nay formal rehabilitation or regular exercise. There were 50 men and 10 women, ranging in age from 30 to 81 with an average age of 60. The time interval between the acute attack and the exercise test ranged from one month to 9 years. Even though severe infarction affects the exercise capacity for a long time after an acute attack, its effect on cardiac function was more obvious than that on physical capacity. Age was the most important determinant of physical capacity, and the slope of decreasing physical capacity with age in patients with infarct was the same as that in normal subjects. Cardiac function also decreased with age. However, during the early recovery phase, cardiac function was influenced by the severity of infarction and the influence of age could not be established. There was no significant correlation between early ambulation and physical capacity. The beneficial effects of early ambulation may be lost if physical activity is discontinued for some time after the acute attack. The physical capacity increased 2-3 years after the acute attack, but myocardial function did not change significantly.

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Out of 330 patients with acute myocardial infarction (AMI) admitted to our institution, 256 patients entered our 3-week rehabilitation program and discharged from the hospital. Through the execution of the program, its feasibility and safety were examined, and guidelines for the progress of the program were re-evaluated. The state of outpatient community life and its determining factors were also investigated by a questionnaire. The following results were obtained: 1) Over 90% of patients with uncomplicated MI could complete the rehabilitation nearly on schedule, indicating the feasibility of the program. 2) Mortality after ambulation and serious complications related to rehabilitative activities were very few, indicating the safety of our rehabilitation program. 3) Among guidelines for the progression of the program generally accepted, the case for tan elevation of blood pressure as well as an ST depression was found to be especially important in order to prevent serious complications. 4) Age, discharge exercise capacity, left ventricular function and the severity of coronary disease were important factors influencing the patients' returning to work.

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The relative benefits of 4- and 8 week rehabilitation programs were compared in inpatients with myocardial infarction. In the 8-week program, complete bed rest was instituted for the initial 3 days, followed by walking around the bed from the 14th day ; exercise was gradually increased to target levels such as walking for distances of 500 m per time up to a total of 2 to 3 km and climbing up and down several sets of 20 stairs daily. In the 4-week program, complete bed rest was provided for the initial 3 days, and exercise was more rapidly increased for 4 weeks to reach the same exercise level as that of the 8-week program. The duration of hospitalization, and the clinical progress, prognosis and the ability to return to work after discharge of the patients were compared in each program. The percentage of patients who were hospitalized for 40 days or less increased from 0% in the 8-week program to 15.9% in the 4-week program, while the percentage of patients who were hospitalized from 41 to 60 days increased from 13.3 to 37.0% . Shortening of the program did not cause significant differences in the incidence of serious complications such as heart failure, arrhythmia and infarction. The 2-year mortality was 15.9% in the 8-week program and 7.9% in the 4-week program. The state of work after discharge was comparable in both programs. Exercise tolerance, measured by bicycle ergometer, tended to improve remarkably 6 months after infarction. Based on the above results, the 4-week program is considered to be more practical than the 8-week program.

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The aim of the present study is to design a new protocol of low-level treadmill exercise testing suitable for an evaluation of exercise tolerance capacity in patients convalescing from acute myocardial infarction and also to determine the two-step exercise equivalent in energy cost to treadmill exercise of various levels of work load. The whole material consisted of 42 healthy men aged from 24 to 37. They conducted a low-level treadmill exercise testing consisting of 5 stages, which began with the belt speed (v mph) = 1.0 and the slop (G%) = 0 in the first stage and went up to 2.5-mph speed and 12% slope in the fifth one. They also performed 6 stages of intermittent two-step exercise on a Master's original staircase at 10 to 60 trips per 3 min. Thirty and eleven men of the study material exercised on 3 two-step staircases, which differed in the step height (15, 19 and 22.9 cm), at 30 trips and at 20, 30 and 40 trips per 3 min, respectively. The energy expenditure of the low-level treadmill exercise was expressed in the following formula obtained from the data on the whole material : oxygen uptake ( V^^·₂, ml/kg·min) = 8.29+0.98v²+0.25v·G, with r = 0.90 (p<0.01) : V^^·o₂(ml/kg·min) = 6.85+1.17f, with SEE =1.84. There was also a significant linear correlation between V^^·o₂ and the height of the step (h cm) in the data from the 30 men (r = 0.77, p<0.01), the regression equation being V^^·o₂(ml/kg·min) = 5.21+0.58h. The results from the 11 men showed that V^^·o₂ could be expressed as a function of f and h in two-step exercise ; V^^·o₂(ml/kg·min) = 6.10+0.05f·h was obtained with SEE = 1.47 (r = 0.90, p<0.01). The heart rate (HR) significantly correlated with V^^·o₂ in both treadmill (r = 0.70, p<0.01) and two-step (r = 0.84, p<0.01) exercise. The regression equation was HR = 68.3+2.11 V^^·o₂ (SEE = 10.5) in treadmill exercise, and HR = 63.1+2.53 V^^·o₂ (SEE = 11.4) in two-step exercise. The excellent similarity observed in these 2 equations indicates that the heart rate response is nearly identical in these 2 modalities of exercise when O₂ uptake is the same. A new protocol of a low-level multistage treadmill exercise testing was designed, in which the energy cost was 2.5 METs in the first stage and 3 METs in the second one, and subsequently, its increment was 1 MET between the 2 neighbouring stages. The two-step exercise which corresponded in energy cost to each stage of the low-level treadmill exercise protocol was tabulated with the number of trips under 3 different staircases. These data could provide necessary information in comparing the results of these 2 modalities of exercise and also in performing rehabilitative exercise over a two-step staircase after exercise prescription made with a low-level treadmill exercise testing, the latter of which is the ultimate purpose of the present study.

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Twenty cases with effort angina underwent exercise training for a mean follow-up period of 38 weeks. Various parameters were investigated to clarify whether or not such parameters can be used to predict an increase in exercise tolerance of patients with effort angina. The increase of exercise tolerance after training was found to be related to a reduction of the myocardial oxygen demand at a given external work load. The maximal heart rate (max HR) the maximal systolic blood pressure (max SBP) and the maximal rate-pressure product (max RPP) could not predict the post-training increase in exercise tolerance. Before training, the maximal oxygen intake (V^^·o₂ max) was found to be lower, and the HR/ V^^·o₂ max and the SBP/V^^·o₂ max were higher in the group (11 patients) which showed a good response to the exercise program (effective group) than those in the group (9 patients) which did not (unchanged group). Before training, the HR/V^^·o₂ max and the SBP/V^^·o₂ max in the effective group were also higher than those of 96 healthy adults. On the other hand, the HR/V^^·o₂ max and the SBP/V^^·o₂ max in the unchanged group were not different from those of the healthy adults throughout the training. It is useful to compare the values of the HR/V^^·o₂ max and the SBP/V^^·o₂ max of patients with effort angina to those of healthy adults for the prediction of post-training increase in exercise tolerance.

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We studied the relationship between the mental disorders and the mental severities of 163 patients with acute myocardial infarction (AMI), who were admitted to the CCU (Coronary Care Unit) of Nippon Medical School Hospital during the past 2 years. Their mental disorders were diagnosed by psychiatrists, and the relationship between their physical severities according to Killip's classification and their mental severities was investigated. Based on these studies, the authors described the way to manage AMI patients in a CCU, especially from a psychiatric point of view. 1) About 64% of all the patients showed some mental disorders, and many of them were in a state of anxiety or depression. In most of the cases their mental severities were considered to be mild or moderate. 2) We found some correlation between physical severities according to Killip's classification and mental severities (r = 0.3061, p<0.005). Many patients with grade I of Killip's classification showed a normal or mild severity, and many with grade II had a mild or moderate severity. About one half of the patients with grades III and IV showed moderate and sever severities, respectively. 3) About 26% of the subjects were in need of psychotropic medication. 4) About 10% of the subjects showed disorientation or cloudy consciousness. The mental severity of patients with an acute lidocaine intoxication was sever. These results showed that there was a significant correlation between physical severity according to Killip's classification and mental severity of AMI patients in the CCU. Patients whose physical severity was not so great showed comparatively mild mental disorders. As Killip's grade of physical severity progressed, mental disorder became more severe.

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We designed a rehabilitation program for patients with post-myocardial infarction by modifying the 14-step program of Emory University into a more suitable form for a Japanese. The usefulness of this rehabilitation program was evaluated by comparing the clinical course of our patients with that of the patients in our affiliated institutions, where patients had no systematic rehabilitation therapy. The following results were obtained: 1) Most patients of the rehabilitation-completed group were living a non-restricted life 6 months after discharge. The life style of the rehabilitation group even including the rehabilitation-non-completed group, was far better than that of the non-rehabilitation group. 2) Many patients of the rehabilitation group were working at the same job as before infarction 3 years after discharge, while a substantial number of the patients of the non-rehabilitation group had changed their job or retired within 3 years after discharge. 3) The reason for changing job or retiring was primarily subjective symptoms or objective findings in the rehabilitation-completed group, while it was mostly fear in the non-rehabilitation group. 4) Patients who could not complete our program were mainly old patients of over 70 years of age, patients with extensive anterior infarction and subendocardial infarction and ones with complications such as shock and cardiac failure.

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Semi-supervised physical training for 12 weeks was performed on 60 patients with coronary heart disease including 48 patients with myocardial infarction and 12 with angina pectoris. The training program consisted of medically-supervised training at the institute once a week and unsupervised training at home at least twice a week with an intensity of 70 to 85% of the maximum heart rate which had been attained by a symptom-limited multiphasic treadmill stress testing according to Bruce's protocol. The results showed an average increase of maximum oxygen consumption from 27.0 ± 5.7 to 31.0 ± 7.8 ml/min·kg (p<0.01) and of treadmill time from 507 ± 120 to 673 ± 140 sec (p<0.0001). Cardiovascular responses reduced at a submaximal level of exercise and remained unchanged at the maximal level of exercise. No detrimental events were encountered during the program. The left heart catheterization and coronary angiogram were performed on 35 out of 60 patients. The trainability was higher in patients with single-vessel disease than in those with multi-vessel disease. Based on these results, supervised training should be required mostly for patients with low physical fitness, and patients with high physical fitness can probably improve their physical abilities by self-training at home following a proper exercise program.

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In order to investigate how rehabilitation during hospitalization influences the prognosis of patients with acute myocardial infarction, the authors investigated 496 cases, including 405 males and 91 females hospitalized in the institutes participating in the Cardiac Rehabilitation Research Conference, during the period of 10 years from 1969 through 1978. Patients' ages averaged 59.2 years for males and 66.5 years for females. The total number of deaths during the average follow-up period of 5 years and 7 months was 104 (21.0%), of which 73 cases of cardiac death were included, showing 14.7% of the total cases and 70.2% of the total deaths. The incidence of bed-ridden patients after discharge was as low as 1.0%, and the rate of returning to work varied according to age: it decreased from 86.7% to 9.3% with age, averaging 54.4%. The rate of rehabilitation performance in the hospitals was 73.7% for patients under 69 years of age and 48% for those under 70. The rate of cardiac death was 8.4% in the rehabilitated group (exercise group), and 27% in the non-rehabilitated (control) group, and the rates of returning to work were 50.2% and 25%, respectively and there were significant differences in both the mortality rate and the working rate between these 2 groups (p<0.01). As for the severity of myocardial infarction, the more severe the disease, the wider the difference in the prognosis between the exercise and the control group.

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