ISSN:0009-7322    

出版商:OVID    

年代:1968

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

In order to determine whether there is any interference with left atrial emptying or left ventricular filling in idiopathic hypertrophic subaortic stenosis (IHSS) and aortic stenosis, the fall in pressure (y descent) of the left atrialvwave following the opening of the mitral valve was analyzed in 27 patients with IHSS and in 22 patients with valvular aortic stenosis, and the results were compared to those for 13 normal subjects and 24 patients with mitral stenosis. The y descent in 0.1 sec and the mean rate of the y descent, as well as the maximum rate of decline, were reduced in all three groups of patients, as compared to those of the normal group. The changes in IHSS were more marked than those occurring in patients with aortic stenosis or mitral stenosis. These findings in patients with IHSS and valvular aortic stenosis appear to result from reduced left ventricular compliance. It is concluded that there is an impairment of left ventricular filling in IHSS and that obstruction to ventricular inflow, as well as to outflow, contributes to the hemodynamic changes in this condition.

ISSN:0009-7322    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

The vectorcardiographic diagnosis of left ventricular hypertrophy, using the Frank lead system, was evaluated in 93 autopsied male patients (70 with hypertrophy of the left ventricle and 23 without such hypertrophy). The criterion of the maximal QRS magnitude in the transverse plane greater than 2.2 mv below the age of 50 years and 1.8 mv at the age of 50 or more was positive in 61% of hypertrophied hearts and negative for all the nonhypertrophied hearts. The criterion of the T loop vector greater than H°-70° in the transverse plane was positive in 82% of 49 hypertrophied hearts and positive in one (7%) of 15 normal hearts for which the T loop was available.The maximal QRS magnitudes in the frontal and sagittal planes had too low a sensitivity to be of value while the angles of the maximal QRS vector in the transverse and sagittal planes was too nonspecific to be useful.By combining the QRS magnitude and the T loop vector in the transverse plane, the diagnosis of left ventricular hypertrophy was made in 90% of 49 hypertrophied hearts for which the T loop was available.

ISSN:0009-7322    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

Evidence of peri-infarction block was found in 39% of the electrocardiograms of 1,938 patients with definite evidence of myocardial infarction. It most commonly occurred acutely or within several days following infarction and was more common with recurrent infarction. Peri-infarction block infrequently disappeared and was associated with higher values for serum glutamic-oxalacetic transaminase and a greater mortality in the first year following myocardial infarction. There was no autopsy correlation of peri-infarction block and ventricular aneurysmal formation.The term "peri-infarction block" is appropriate only when abnormal intraventricular conduction occurs in association with definite electrocardiographic evidence of myocardial infarction.

ISSN:0009-7322    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

Activity of the renin-angiotensin-aldosterone system was investigated in 53 patients with benign essential hypertension treated with thiazides. Following acute (less than 3 weeks) exposure to thiazide, renin activity was increased in peripheral plasma and sensitivity to infused angiotensin was decreased but only when dietary salt was simultaneously restricted. During chronic (more than 2 months) exposure to hydrochlorothiazide, 32 patients with unrestricted salt intake had normal renin activity in peripheral plasma (39 of 43 determinations), normal sensitivity to infused angiotensin (18 of 22 tests), and normal aldosterone excretion (nine of nine assays). Renin activity correlated well with angiotensin sensitivity (r=0.661;P<0.001). Therefore, chronic ingestion of thiazide apparently induces no change in the renin-angiotensin-aldosterone system and hence presumably neither secondary aldosteronism nor negative sodium balance.

ISSN:0009-7322    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

Observations on the blood pressure of a group of 660 displaced male Tibetans revealed striking dissimilarities in regard to the mean systolic and diastolic figures as compared to those reported for Europeans and Americans. The average Tibetan figures are lower than those of Western populations; however, a comparable variability after the fourth decade and a parallel spread of values with age and weight were found in the Tibetan data. The socioeconomic status and height bore no relation to the blood pressure levels. The results obtained from this survey on the Tibetans are compared with those of other Mongolian groups. It is suggested that the differences of blood pressure among related Mongolian groups and populations studied in the West are largely determined by environment.

ISSN:0009-7322    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

Amiloride, a new, well-tolerated oral natriuretic and mild diuretic agent, has been evaluated alone and in combination with other diuretics. Its remarkable ability to promote retention rather than loss of potassium makes it a useful adjunct in the management of even the most severe edematous states. It also retards the alkalosis produced by certain of the stronger diuretics by blocking hydrogen secretion and promoting bicarbonate loss. In addition to being a valuable adjunctive agent, the compound may be useful alone because of the advantages inherent in steady, sustained natriuretic therapy with a mild diuresis as opposed to incurring precipitous alterations in fluid and electrolyte balance with the intermittent use of more potent agents. In certain patients it was mildly antihypertensive.Amiloride produced marked increases in aldosterone secretion with lesser rises in plasma renin. The adrenal stimulation therefore appeared to result from both potassium retention and renin activation consequent to natriuresis.The compound appears to act primarily in the distal nephron, blocking both sodium-hydrogen exchange and sodium-potassium exchange. Like triamterene, but unlike spirolactone, amiloride has the characteristics of a noncompetitive inhibitor of aldosteronedirected sodium and potassium transport. Because of this, it may be expected to produce more predictable effects than spirolactone and at least in certain instances to be more powerful. It may also be preferable to spirolactone for the acute control of derangements in potassium balance because of its more rapid onset and disappearance of action.No significant toxicity was encountered; however, serum potassium values should be carefully monitored, especially in situations involving impaired renal function.

ISSN:0009-7322    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

Guanethidine was administered to 10 normal subjects in order to examine the effects of reduced adrenergic function on plasma volume. An increase in the plasma volume was observed averaging 21.4% after 1 week, and 12.1% and 13.1% after 2 and 3 weeks of drug administration. A similar change in plasma volume resulted when alphaadrenergic blockade was produced with phenoxybenzamine. These changes occurred in the absence of sodium retention and were associated with attenuation of forearm venous sympathetic reflexes and a rise in forearm venous compliance. The increase in venous compliance which was observed was proportional to the changes in plasma volume in these subjects. Thus, the sympathetic nervous system through its control of venous resistance may provide a means whereby the blood volume can be regulated.

ISSN:0009-7322    

出版商:OVID    

年代:1968

数据来源: OVID

摘要:

In a 14-month-old patient who had been repeatedly hospitalized for recurrent pulmonary infections, cardiac angiography found "absence" of the left pulmonary artery, but thoracic aortography demonstrated that a rudimentary patent ductus filled a distal patent pulmonary artery. There was a coexistent vascular ring with a retroesophageal right subclavian artery.At surgical exploration it was possible to mobilize the distal left pulmonary artery and perform a direct anastomosis between the left pulmonary artery and the main pulmonary artery. This is perhaps the first patient in whom such an operation has been performed. It is emphasized that the absence of a pulmonary artery on pulmonary angiography does not indicate that the entire pulmonary artery is absent. The presence of a patent and surgically reconstructable distal pulmonary artery can be determined only by aortography or possibly by surgical exploration.

ISSN:0009-7322    

出版商:OVID    

年代:1968

数据来源: OVID