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We studied the relationship between physical activity and ambulatory blood pressure (BP) in young and older shiftworkers by simultaneous recordings of activity, blood pressure and pulse rate (PR). Activity was assessed using Activetracer, a self-contained microcomputer with an acceleration sensor, attached to a waist belt. Ambulatory BP was monitored every 30 minutes for 48 hours with a TM2421. Three types of hemodynamic responses were noted in relation to the physical activity. The balance type, in which both BP and PR increase with physical activity, was observed in 5 of 10 young cases (50%) but only in 1 of 7 older cases (14.3%). The BP response type, in which the BP increases with no change in the PR, was observed in 6 of the 7 older (86%) but only in 3 cases in the young group (30%). The PR response type, in which only the PR increase correlated with activity, was observed in 2 cases in the young group (20%) and none in the older group. The difference in systolic BP between periods of activity and rest in the older shiftworker was significantly larger than that in the young group (15.9 +/- 6.4 vs. 5.9 +/- 6.6 mmHg, p < .01), although no significant difference was observed in diastolic BP. In contrast, the increase in pulse rate after movement was significantly higher in the young group (4.4 +/- 4.0 vs. 9.0 +/- 4.8 bpm, p < .05). Thus, the fluctuation of the systolic BP was more dependent on physical activity in the older group, whereas PR variations correlated with the physical activity in the young group.

In order to evaluate the effects of aging on cardiopulmonary receptor function in hypertensive patients, hemodynamic responses after unloading were studied in middle aged and older hypertensive patients. Twenty-one hypertensive patients were divided into 2 groups according to age. The younger group consisted of 9 patients less than 65 years old (mean age: 57.2 years) and the older group contained 12 patients more than 65 years old (77.2 years). Following 10 min rest, deactivation of cardiopulmonary receptors was obtained by reducing central venous pressure through the application of graded negative pressures of -10, -20, and -40 mmHg to the lower body. Blood pressure, pulse rate, and forearm blood flow were measured at baseline and at each level of negative pressure. Furthermore, plasma norepinephrine and plasma renin activity levels were measured at baseline and at -40 mmHg. Forearm blood flow was measured by venous occlusive plethysmography using a Silastic strain gauge applied around the forearm. Forearm peripheral vascular resistance was calculated by dividing the mean arterial pressure by the forearm blood flow. Baseline mean blood pressure, pulse rate, and peripheral vascular resistance were similar in both age groups. Following lower body negative pressure (LBNP), mean blood pressure and pulse rate did not change, suggesting the selective deactivation of cardiopulmonary receptors. The increase in peripheral vascular resistance at LBNP of -40 mmHg in the older group (20.0 +/- 6.2) was significantly lower than that in the younger group (15.5 +/- 8.9, p less than 0.05). Furthermore, the increase in peripheral vascular resistance after LBNP was inversely related to age (Y = -0.32X + 38.8, r = -0.43, p less than 0.05). Increases in plasma norepinephrine and plasma renin activity in the older group were not different from those in the younger group. It is concluded that the sensitivity of cardiopulmonary baroreceptor function in hypertensive patients deteriorates with increasing age.

We examined the efficacy of the combination of coronary reperfusion and calcium-activated neutral protease (CANP) inhibitor (E-64c) for the treatment of acute myocardial infarction in dogs. In 34 dogs, the left anterior descending artery (LAD) was occluded and reperfused after 1 hour (Groups A and B). In the remaining 49 dogs, the LAD was ligated (Groups C and D). E-64c (100 mg/kg, Groups A and C) or vehicle (Groups B and D) was injected intravenously before and after the coronary occlusion or ligation. After 24 hours the hearts were removed. The proportion of the infarct size in the LAD perfusing area (risk zone) in Group A was 47.3 +/- 9.7%, significantly lower than in Group C (54.8 +/- 8.2%, p less than 0.05) or Group D (58.7 +/- 10.0%, p less than 0.01). There was a significant difference between Group B (52.9 +/- 8.6%) and Group D as well (p less than 0.05). The effects of reperfusion (p = 0.0016) and E-64c (p = 0.0226) per se on infarct size were significant, but the combination of reperfusion and E-64c was not additive. The decrease in CPK activity in the risk zone was significantly lower in the reperfused group (p = 0.0001). The mCANP activity was higher in the border zone and lower in the infarct zone. The trend in the mu CANP activity was similar to that of mCANP. Thus, treatment with a CANP inhibitor in the early phase of acute myocardial infarction may be marginally beneficial in combination with reperfusion.

The correlations between blood pressure, left ventricular hypertrophy and left atrial enlargement were examined in 2,010 autopsied cases. The cases were classified into 3 groups: 972 (48.2%) normotension cases, 313 cases (15.5%) of systolic hypertension and 725 cases (36.1%) of diastolic hypertension. The incidence of left ventricular hypertrophy (LVH) was significantly higher in systolic and diastolic hypertensive cases than in normotensives (p less than 0.05), but no significant difference in LVH incidence was found between the 2 hypertensive groups. The incidence of an enlarged left atrium was also significantly higher in both hypertensive groups than in the normotensive group (p less than 0.05). The incidence of congestive heart failure and a large CTR were also higher in both hypertensive groups. However, there were no intergroup differences in atrial fibrillation incidence, despite significant differences in atrial size. Finally, the incidence of moderate to severe coronary artery stenosis was significantly higher in both hypertensive groups, but no difference was found between the 2 types of hypertension. We concluded that both systolic and diastolic hypertension contributed to the genesis of left ventricular hypertrophy, left atrial dilatation, coronary sclerosis and congestive heart failure.

The 4 year prospective trial on the effectiveness of the antihypertensive treatment was performed in 100 mild hypertensive patients of the aged, the average age being 76.1 years. Dropouts during the drug-off control period were 9 cases. The matched pair group was selected by the age, sex, and blood pressure. Forty-four drug treated cases and 47 placebo treated cases were comparable in blood pressure as well as in laboratory data. Cerebrovascular and cardiac complications were observed in 4 cases or 10.5% in the drug group, and in 9 cases or 22.0% in the placebo group. When 8 cases of blood pressure elevation over 200/110 mmHg in the placebo group were added to the cardiovascular complications, dropouts in placebo group reached 41.5%, and this showed the significant difference. Other complications were observed in 12 cases or 31.6% in the drug group and in 17 cases or 41.5% in the placebo group. Major complications were cancers, infections, and bone or joint diseases. Blood pressure was decreased from 171/87 to 151/80 in the drug group, and the average decrease was 20/7 mmHg in 4 year period. No significant changes in hematocrit, serum protein, urea nitrogen, uric acid, sodium, and potassium were observed during the trial period. The present study suggested that antihypertensive treatment was effective in the aged with mild hypertension, and that careful follow up was needed not only for cardiovascular complications but also for general health condition.

Ten mg of Nifedipine, a Ca++ antagonist, was administered orally in 2 groups of patients; Group 1: 6 patients in hypertensive emergency and Group II: 12 patients with intractable, severe hypertension. Following results were obtained. 1) A marked hypotensive effect was observed in all patients of Group I. The maximum effect was observed within 30 to 60 min and lasted for approximately 180 min. Clinical symptoms also improved remarkably with the fall in blood pressure. Any side effect was not observed. 2) A marked hypotensive effect was observed in all cases of Group II. The blood pressure fell by 21.4% systolic (p less than 0.01) and 19.4% diastolic (p less than 0.02). The peripheral vascular resistance also showed the decrease by 26.2% (p less than 0.01). The heart rate and cardiac index increased slightly. It was suggested that the hypotensive mechanism of this preparation is due primarily to the peripheral vasodilation.

Seven elderly cases with reversible electrocardiographic changes simulating acute myocardial infarction in the absence of gross myocardial infarction on postmortem examination were observed following the blood transfusion. The underlying diseases were cancer of gastrointestinal tract or gall bladder in 4, gastric ulcer in 2, and 1 of pseudomembranous enterocolitis. The electrocardiogram revealed the abnormal Q waves with monophasic ST elevation and following coronary T inversion. These findings lasted only for 2 to 7 days and returned to the previous normal tracings. The hematocrit was elevated from 28.9 to 47.7 after the blood transfusion of 800 to 1,800 ml. The disseminated intravascular coagulation was shown in 5 cases. GOT levels were within normal ranges except 1 case. Pathological findings in cases with recent electrocardiographic changes were characterized by the mural thromboses, extending into the myocardium through the Thebesian vein. The focal small necroses of the adjacent myocardium or around the thrombosis of small vessels were also observed. In the later phase the fine interstitial fibrosis took place after the resorption of the thrombi and necrotic foci. From these clinical and pathological findings we proposed a new concept of reversible myocardial infarction induced from the hypercoagulability, disseminated intravascular coagulation, and elevated hematocrit.

Three cases of isolated right ventricular infarction resulting from thrombotic occlusion of a hypoplastic right coronary artery were found in 4,000 consecutive autopsies performed at Tokyo Metropolitan Geriatric Hospital. The incidence of isolated right ventricular infarction was 0.08%. The clinical profile of the first case was characterized by shock, pulmonary congestion, pleural effusion, decreased V1R and V2R on ECG, a small elevation of CPK and transaminase, elevation of fibrin degenerative products and decreased platelet count. The patient responded to volume expansion, heparin and catecholamines. One year later she died from cerebral bleeding. In the second case, mild aortic regurgitation and atrial fibrillation were present. He died suddenly during an episode of pneumonia. In the third case, there was chronic obstructive lung disease, atrial fibrillation and lung cancer. He died of respiratory failure. On autopsy, the coronary arteries revealed a marked left dominant and right hypoplastic pattern in all cases. The right coronary artery perfused only the free wall of the right ventricle. Complete occlusion of the hypoplastic right coronary artery resulted in isolated right ventricular infarction. In addition, chronic pulmonary disease and arrhythmia may be contributory.