ISSN:0009-7322    

出版商:OVID    

年代:1966

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1966

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1966

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1966

数据来源: OVID

摘要:

The influence of respiration on the flow of blood from the abdominal vena cava into the thorax was studied in 15 patients with pulmonary emphysema and in 10 control subjects without thoracic disease or heart failure. In control subjects, during quiet breathing blood flowed into the thorax throughout the respiratory cycle at a rate which was greatest during inspiration. Simultaneously the transmural pressure of the abdominal vena cava fell and transmural right atrial pressure increased. The same pattern of flow was observed in nine of the patients with emphysema. In the other six patients, however, flow was greatly reduced or completely arrested during inspiration, with simultaneous increase in transmural caval pressure and reduction in transmural atrial pressure. This inspiratory obstruction at the thoracic inlet was associated with gross hyperinflation of the lungs and a low diaphragmatic position. It probably was not the result of the high negative and positive intrathoracic pressures that develop duringinspiration and expiration, respectively, in such subjects.It is possible that this phenomenon may account for the peripheral edema that occurs in patients who have emphysema without associated pulmonary hypertension or cardiomegaly.

ISSN:0009-7322    

出版商:OVID    

年代:1966

数据来源: OVID

摘要:

Nine patients with cor pulmonale due to chronic obstructive pulmonary disease were studied by means of right and left heart catheterization. Hemodynamic and respiratory observations were made during a control period and during the infusion of 1 g of aminophylline.Aminophylline produced a significant reduction in mean pulmonary artery pressure from 39.4 to 25.4 mm Hg, in right ventricular end-diastolic pressure from 8.6 to 2.1 mm Hg, in left ventricular end-diastolic pressure from 7.9 to 3.0 mm Hg, and in brachial artery mean pressure from 95.3 to 85.6 mm Hg. The heart rate and oxygen consumption increased, but there was no change in cardiac index. The alveolar ventilation increased significantly from 2.1 to 2.9 L/min/m2(BTPS).Evidence is presented to suggest that the decrease in pulmonary artery pressure was due to pulmonary arteriolar dilatation.

ISSN:0009-7322    

出版商:OVID    

年代:1966

数据来源: OVID

摘要:

The present report concerns ten patients with significant tricuspid stenosis and atrial fibrillation. The diagnosis could be made clinically in only two patients and by pullback record from right ventricle to right atrium in three, including the two mentioned previously. Careful hemodynamic assessment of tricuspid valve function by using simultaneously recorded right atrial and right ventricular pressures resulted in the detection of significant tricuspid stenosis in the nine patients on whom these measurements were made. The influence of atrial fibrillation and respiration on the tricuspid gradient and the role of exercise and amyl nitrite in augmenting barely detectable resting gradients are demonstrated.

ISSN:0009-7322    

出版商:OVID    

年代:1966

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1966

数据来源: OVID

摘要:

The relation between cardiac norepinephrine concentration and the functional state of the myocardium was studied in left ventricular papillary muscles removed from patients with congestive heart failure at the time of mitral valve replacement. Myocardial function was assessed by determining the maximum isometric active tension that the papillary muscle could develop in an in vitro system, and by measuring the increase in active tension in response to the norepinephrine-releasing sympathomimetic amine, tyramine. The norepinephrine concentration averaged 0.36 &mgr;g./Gm. in 17 muscles. In eight of these a response to tyramine was observed with a 21-per cent increase in active tension, and the norepinephrine concentrations averaged 0.53 &mgr;g./Gm.; in the other six muscles tested with tyramine no positive inotropic response was observed, and the norepinephrine concentration was significantly lower, averaging 0.16 &mgr;g./Gm. The maximum active tension in 17 muscles averaged 1.78 Gm./mm.2, and a significant positive correlation between the maximum tension and the norepinephrine concentration of the individual muscles was observed. In the eight muscles responding to tyramine, the maximum tension observed, 2.34 Gm./mm.2, was significantly greater than that observed in the six muscles unresponsive to tyramine, 0.64 Gm./mm.2It is concluded that norepinephrine depletion appears to be associated with defective myocardial function although no causal relationship between these two abnormalities has been established.

ISSN:0009-7322    

出版商:OVID    

年代:1966

数据来源: OVID

摘要:

Measurements of flow and pressures related to the left heart were made on 21 patients immediately prior to and at intervals of 2 and 4 minutes after angiocardiography. These patients had normal mitral valves (group 1), mitral incompetence (group 2), or mitral stenosis (group 3). There was an increase in left ventricular end-diastolic pressure accompanied by an increase in “pulmonary artery wedge” (PA wedge) pressure in all patients. Patients with mitral valve disease generally develop higher PA wedge pressures; those with mitral stenosis develop, in addition, significantly increased mean diastolicand end-diastolic gradients across the mitral valve.These increased gradients in mitral stenosis are due to increased flow across the mitral valve, which results from a combination of increased cardiac output and decreased diastolic filling time. Diagnostic angiocardiography affords an opportunity of observing the effects of valve lesions at a higher flow rate and is particularly useful in those patients with normal PA wedge pressure and small gradients initially.

ISSN:0009-7322    

出版商:OVID    

年代:1966

数据来源: OVID