摘要:

Throughout our professional lifetimes, we are conditioned by the need to choose: among careers, among treatments for our patients, among health habits and lifestyles. After detailing the extent to which a choice‐making orientation has dominated our lives, our society, our health system, our science, this paper describes areas in which it is crucial that choicesnotbe made. These include the choice between basic and applied research, between targeted and investigator‐initiated research, between prevention and treatment of cardiovascular disease, and between the need to know (research on mechanisms of disease) and the need to take action (intervention in the individual and the community to control disease). In each of these areas, a decision to emphasize either alternative at the expense of the other is undesirable and defeats the basic goals of understanding and controlling heart and vascular disease.In discussing these sets of alternatives, the three major cardiovascular risk factors are discussed: cigarette smoking, high blood pressure and diet. Examples are chosen from research investigations on risk, intervention, treatment, prevention and community control.

ISSN:0009-7322    

出版商:OVID    

年代:1982

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Physical training is thought to be a stimulus for coronary vascular growth and coronary collateral development. This report is a summary of knowledge in the area. Studies in experimental animals with normal hearts indicate that physical training promotes increased myocardial capillary density and also causes enlargement of the surface coronary vessels. The physiologic effect of these changes on coronary vascular reserve and protection of segments of the heart against myocardial ischemia has not been established. Physically trained dogs and pigs do not appear to be protected against the effects of coronary occlusion, in that the ischemic area appears to be as large in trained animals as in untrained animals for any given coronary lesion. One study in physically trained rats appears to show protection against myocardial infarction, but whether this is related to coronary vascular changes has not been established. Experiments in dogs subjected to chronic narrowing or gradual occlusion demonstrate that physical training in these models does promote collateral blood flow as measured by retrograde flow in open-chest experiments. Studies using the microsphere technique in closed-chest animals confirms increased collateral flow ischemic areas in some animals, but the magnitude of the increases appears to be small and varies greatly from animal to animal.Studies in athletes suggest that myocardial blood flow is lower at any submaximal level of training athletes than in sedentary persons. Studies in patients with coronary artery disease have generally failed show an increase in coronary blood flow or in perfusion of ischemic areas after physical training programs, but the techniques used might not have been sensitive enough to detect changes.The evidence in the experimental animals is sufficiently promising to indicate that the search should continued to define physical training programs that will most stimulate myocardial vascularity and coronary collaterals in humans.

ISSN:0009-7322    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

A prospective electrocardiographic study was designed to establish baseline values for electrocardiographic measurements, with specific reference to the QT interval during infancy, and to test the "QT hypothesis" for the sudden infant death syndrome (SIDS). In this ongoing study, ECGs are recorded on the fourth day of life and in the second, fourth and sixth months. The state of health at 1 year is ascertained by a phone call. So far, 4205 newborns have been enrolled. The mean QTc (QT interval corrected for heart rate) was 397 ± 18 msec (± SD) at the fourth day, 409 ± 15 msec (p < 0.0001) at the second month, and 406 ± 15 msec at the fourth month; by the sixth month, it returned to 400 14 msec. In 88 newborns, the QTc increased by over 40 msec at the second month. Among the 2000 infants checked at year, there have been three sudden and unexpected deaths. The QTc of one'of the victims at the fourth day was 563 msec, which exceeded the mean by more than 9 standard deviations, while the QTc of the other SIDS victims exceeded the mean by more than 2 and 3 standard deviations. These results are consistent with the “QT hypothesis,” but more data are necessary before any conclusion on the potential relationship between QT interval prolongation and SIDS can be'drawn. This study provides definitive waking normal values for' QT interval in infancy and indicates that the QT interval lengthens physiologically and temporarily during the first months of life. In some infants, this lengthening may transiently impair cardiac electrical stability.

ISSN:0009-7322    

出版商:OVID    

年代:1982

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

The treatment of paroxysmal supraventricular tachycardia (PSVT) in infancy with digitalis, adenosine triphosphate (ATP) and verapamil is reported. Treatment was successful in about 90% of the patients treated with ATP and verapamil and in 61-71% of the patients treated with digitalis (Lanatoside C). Verapamil terminated the tachycardia within 2 minutes of administration in most instances and ATP less than 1 minute. Digitalis, however, took as long as 2 hours; it was therefore excluded as the drug of first choice in emergencies, and is better suited for treating patients with poor hemodynamics.Side effects with ATP are common but short-lived. With verapamil, side effects are rare, but may serious if certain contraindications are not taken into account. Digitalis in the dose used in this trial rarely produced side effects.We conclude that ATP or verapamil is the drug of first choice for quick termination of PSVT in infancy.

ISSN:0009-7322    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

We report 21 patients with discrete subaortic stenosis (DSS) causing mild obstruction with a peak systolic left ventricular outflow pressure gradients less than 50 mm Hg. They were followed 1-17 years (mean 6.5 years), and eight were recatheterized before surgery, 2-17 years after the first cardiac catheterization.Three patients (14%) had subacute bacterial endocarditis. Ten (48%) had aortic insufficiency, one of whom had no pressure gradient across the left ventricular outflow tract. In three of the 10 patients, aortic insufficiency was found only at the second catheterization. Nine patients (43%) had hyperactive, asymmetric left ventricular contraction; in three, this finding was present only at the second catheterization. Seven of the eight patients who were recatheterized (33% of the entire group) showed an increase in gradient. The increase was from a mean gradient of 35.2 mm Hg to 76.7 mm Hg. Seventeen patients (81 %) had at least one of these four features.In view of these data, we suggest that surgical indications for DSS might be expanded, although definitive recommendations are not possible. All cases of DSS should be carefully followed. Surgery should be performed if signs of progressive complications develop.

ISSN:0009-7322    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

We studied plasma renin activity (PRA) in eight children before and after surgical correction of aortic coarctation. These eight children underwent a combination of low-sodium diet and diuresis before surgery, and PRA was measured shortly thereafter. Thirty-two to 51 months after successful surgical correction, PRAwas measured again. The mean PRAwas 21.4 1.3 ng/ml/hour (± SD) preoperatively and 5.5 ± 1.5 ng/ml/hour postoperatively. These findings provide further evidence of the significance of increased renin-angiotensin activity in patients with aortic coarctation.

ISSN:0009-7322    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Thirty pairs of drinking and nondrinking men, matched for age and weight, were drawn from a working population in which a close relationship between alcohol consumption and blood pressure had been demonstrated. In this smaller sample, men who drank an average of 408 ml of ethanol/week had higher supine (126.9 ± 2.3 mm Hg) and standing (113.3 ± 2.5 mm Hg) systolic and supine diastolic blood pressure (75.5 ± 2.2 mm Hg) than nondrinkers (117.5 ± 2.0, 107.4 ± 2.2 and 68.9 ± 1.8 mm Hg, respectively). Resting plasma concentrations of free and sulfated norepinephrine and epinephrine, renin activity, angiotensin II, aldosterone and cortisol were similar in drinkers and nondrinkers. To investigate differences that may arise when sympathoadrenal activity was stimulated, the subjects underwent a series of standardized physiologic stresses: isometric hand grip, mental arithmetic, cold pressor testing, standing and bicycle exercise. Blood pressure and heart rate responses were similar in drinkers and nondrinkers, although the differences in blood pressure between the two groups tended to become smaller after certain stresses. No differences in the plasma levels of free or conjugated catecholamines were apparent after these stresses. Plasma renin activity increased only after bicycle exercise, and this was similar in both groups. Plasma cortisol levels did not increase. The higher blood pressure in drinkers, therefore, cannot be explained by increased activity of the sympathoadrenal and renal pressor mechanisms.

ISSN:0009-7322    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

Serum total cholesterol level and dietary intake were surveyed 1975–1977 in six Japanese population groups with different lifestyles, including groups in both rural (Akita and Kochi) and urban (Osaka) areas. Clerical workers in Osaka, who had the most westernized lifestyle of all the study groups, had the highest mean serum total cholesterol level (202 mg/dl for men ages 40-49 and 50-59 years), while farmers in Akita had the lowest mean serum total cholesterol level (163 mg/dl for men 40-49 years old, 159 mg/dl for men 50-59 years old, 165 mg/dl for men 60-69 years old). Nutrient intake data for men ages 40-59 years showed 23% of calories from fat for clerical workers in Osaka, the highest among the study groups, whereas farmers in Akita showed a low level of 14%. The ratio of dietary polyunsaturated to saturated fatty acids was over 1.1 for all groups. Cholesterol intake was 339-487 mg/day. Total carbohydrate as a percentage of calories was 53-65%; 75-80% of carbohydrate energy was ingested from cereals. Sugar accounted for less than 3.5% of total calories.In the cross-group correlation analysis between dietary lipid intake and serum total cholesterol, a significant strong positive correlation was found between the dietary lipid factor (44 of Keys et al. and the mean serum total cholesterol level. A weak but significant correlation was observed between the dietary lipid factor and serum total cholesterol for individual inhabitants of Osaka.

ISSN:0009-7322    

出版商:OVID    

年代:1982

数据来源: OVID