ISSN:0009-7322    

出版商:OVID    

年代:1963

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1963

数据来源: OVID

摘要:

This study reveals three cases of corrected transposition (one with total situs inversus) where an accessory flap or umbrella-like formation of the venous atrioventricular valve presented into the outflow tract of the venous ventricle causing severe subpulmonary stenosis.In one case the ventricular septum was intact, while in each of the other two, a ventricular septal defect lay below the obstruction. The latter combination effected a right-to-left shunt at ventricular level.These cases are important because they portray anatomic details of a condition which, although uncommon, is potentially curable. Clinical identification of the subpulmonary stenosis appears best to be accomplished by selective angiocardiography at the level of the venous ventricle.

ISSN:0009-7322    

出版商:OVID    

年代:1963

数据来源: OVID

摘要:

An ultrasound beam directed into a medium of uniform acoustical impedance will travel in a straight line, but a portion of the waves will be reflected at the interface of a medium of different acoustical impedance. A time-distance curve of motion has been obtained from the heart by recording the echoes returned to a send-receive ultrasound transducer applied in the third, fourth, or fifth left interspace. A characteristic curve having two anterior peaks during each cardiac cycle was obtained in the 25 normal patients studied. One peak follows the P wave of the electrocardiogram and is not seen in atrial fibrillation. The other peak of motion toward the anterior chest is followed by rapid regression posteriorly during ventricular diastole. The velocity of the motion was 85 to 160 mm./sec. in normal subjects. In contrast, the records from 90 patients with mitral stenosis demonstrated a distinctive, abnormal pattern having a plateautype configuration with a velocity of posterior motion of only 2 to 35 mm./sec. The configuration of the curve changed toward normal after successful mitral valvulotomy but none of the 35 patients who were studied before and after surgery has developed a calculated postoperative velocity exceeding 70 mm./sec.Twelve patients with “pure” mitral regurgitation have had records similar to the normal, with velocities in or above the normal range. None of the 135 other patients studied, representing a variety of conditions, demonstrated a curve of the type found in mitral stenosis.

ISSN:0009-7322    

出版商:OVID    

年代:1963

数据来源: OVID

摘要:

Hemodynamic effects of isoproterenol infusion were studied in 26 patients with and without mitral valve disease undergoing combined right and left heart catheterization. The heart rate and cardiac output rose while the left ventricular end-diastolic pressure, pulmonary vascular resistance, and total peripheral resistance fell, regardless of the status of the mitral valve. Infusion produced little change in the mean arterial blood pressure and the diastolic filling period per minute.While the mean left atrial and pulmonary artery pressures fell in patients with normal or insufficient valves, these pressures rose in patients with mitral stenosis. Stroke volume tended to rise in all patients but those with mitral stenosis. In patients with combined mitral stenosis and insufficiency the insufficiency appeared to modify the hemodynamic response associated with mitral stenosis.The presence of a lowered end-diastolic pressure in the left ventricle and an increased pressure in the left atrium in patients with stenosis suggests that isoproterenol has a direct or reflex effect on the left ventricle during diastole.

ISSN:0009-7322    

出版商:OVID    

年代:1963

数据来源: OVID

摘要:

Forearm blood flow measurements have been made at rest and after 8 to 10 minutes arterial occlusion in 50 normal and 131 untreated hypertensive subjects. The latter group comprised 91 with essential hypertension; 11 with chronic renal disease (nephritis or pyelonephritis); 21 with renovascular disease; and eight with primary aldosteronism.The resting blood flow increased with the rising pressure in patients with mild hypertension but there was a significant increase in the resting resistance in the more severe cases. The average minimal resistance obtained during reactive hyperemia was greater in hypertensive (3.1 SE 1.0 units) than in normal subjects (2.0 SE 0.07 units). This abnormality was related to the level of blood pressure but not to the duration of the disease.Patients with renovascular disease or aldosteronism presented the same vascular fault as the more common causes of hypertension.Evidence is presented to show that the reactive hyperemia produced maximal dilatation of the forearm vasculature, and acute elevation in pressure in normotensive or acute depression of pressure in hypertensive subjects did not influence the level of resistance achieved by reactive hyperemia.It is concluded that the blood vessels themselves are abnormal in hypertension and that this abnormality may not be related to the activity of vascular smooth muscle.

ISSN:0009-7322    

出版商:OVID    

年代:1963

数据来源: OVID

摘要:

Sixteen patients were studied immediately and for 3 days following surgical closure of ventricular septal defect. In eight patients with absent or mild pulmonary vascular disease, convalescence was uneventful and only small deviations from normal in cardiac output, blood gas levels, and acid-base profile were observed. The remaining eight patients had pre-existing moderate or severe pulmonary vascular disease. Values for cardiac output were abnormally low at some time in the postoperative period in all but two of these eight patients.Failure to survive was clearly related to a low cardiac output in four of the five nonsurvivors. Reduction in cardiac output observed in this group of patients is believed to be based in major part on the pre-existing increased resistance to blood flow through the pulmonary vascular bed and also to impaired right ventricular function following operation. No evidence was obtained to suggest that major changes in pulmonary vascular resistance occurred in the immediate postoperative period in patients with moderate or severe pulmonary vascular disease following closure of ventricular septal defect. Right ventricular function following atriotomy or transverse ventriculotomy was less impaired than after vertical ventriculotomy.

ISSN:0009-7322    

出版商:OVID    

年代:1963

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1963

数据来源: OVID

摘要:

The effect of breathing 100 per cent oxygen on the pulmonary blood volume, pulmonary arterial pressure, left atrial pressure, and pulmonary vascular distending pressure was studied during cardiac catheterization in eight patients with organic heart disease. In half of the patients, a significant decrease in pulmonary blood volume was observed. This decline in pulmonary blood volume in the face of a decrease or no change in the pulmonary distending pressure is interpreted as evidence for a passive mechanism of action for 100 per cent oxygen.The effects of hyperoxia are compared to those of acetylcholine, which works by actively dilating the pulmonary vascular bed.

ISSN:0009-7322    

出版商:OVID    

年代:1963

数据来源: OVID

摘要:

The effect of supine exercise on the pulmonary blood volume was studied in 14 patients with valvular heart disease and in one patient with cardiomyopathy. Statistically significant increases occurred in the pulmonary blood volume (88.6 ± S.E. 20.9 ml./M.2) and in the central blood volume (121.9 ± S.E. 29.2 ml./M.2), whereas left atrial to brachial arterial volume remained unchanged. These results support the concept that, with exercise, increases in central blood volume reflect increases in pulmonary blood volume in patients with acquired heart disease. The increase in pulmonary blood volume and in pulmonary distending pressure suggests a passive expansion of the pulmonary vascular bed with exercise.

ISSN:0009-7322    

出版商:OVID    

年代:1963

数据来源: OVID