Charles W. Crumpton

Effect of Propranolol on Systemic and Coronary Hemodynamics at Rest and during Simulated Exercise

The systemic and coronary hemodynamic effects of relatively large doses of propranolol have been studied following its infusion into intact anesthetized dogs at rest and during simulated exercise. At rest, the administration of propranolol was associated with decreased cardiac output and ventricular work and increased peripheral, pulmonary, and coronary vascular resistances. Coronary blood flow and coronary sinus oxygen content decreased while myocardial oxygen consumption and the index of cardiac efficiency were unchanged. The usual hemodynamic response to mild exercise was obtained, with increased cardiac output, cardiac work, body oxygen consumption, and a modest but insignificant increase in coronary blood flow. When propranolol was given and the same exercise continued, body oxygen consumption, cardiac output, and left ventricular work significantly decreased. Insignificant decreases occurred in coronary blood flow, left ventricular oxygen usage, and coronary sinus oxygen content. The present observations are consistent with the thesis that beta-adrenergic blockade induced by propranolol decreases cardiac work at rest and reduces the cardiovascular response to exercise.

The Physiologic Effect of Contrast Media Used for Angiocardiography

The deaths from angiocardiography at Wisconsin General Hospital were reviewed and found to be two per cent of 249 patients. These 5 deaths are reported briefly. Investigation was carried out to determine the hemodynamic effects of contrast substances on 12 dogs. In general, there was a temporary increase in right atrial and pulmonary arterial pressure followed by a rather marked decrease in systemic arterial pressure and tachycardia. The significance of these findings is discussed in relation to shunts within the heart or between the aorta and pulmonary artery.

Enhancement of Coronary Vasodilating Action of ATP and Adenosine by Lidoflazine

Lidoflazine, a newly developed coronary vasodilator, greatly enhances the coronary vasodilating action of adenosine and ATP. Experiments were designed to study the combined coronary vasodilating effects of adenosine and lidoflazine and to quantify the enhancement of coronary vasodilation of adenosine and ATP by prior administration of lidoflazine. Results of the experiments showed that the combined coronary vasodilating effects of adenosine and lidoflazine can be classified as supra-additive. For 3 hours after the administration of lidoflazine there was a great intensification (20 to 150 times) of the vasodilating action of adenosine or ATP. An adenosine-sparing effect of lidoflazine in whole blood was also demonstrated, and the enhancement of adenosine action is in part related to this effect. It is suggested that lidoflazine may also produce a change in the sensitivity of the smooth muscle of the coronary vessels to the direct or indirect action of adenosine.

The Effect of Hexamethonium Bromide Upon Coronary Flow, Cardiac Work and Cardiac Efficiency in Normotensive and Renal Hypertensive Dogs

Hexamethonium bromide in normotensive and renal hypertensive dogs resulted in significant reductions in arterial blood pressure, cardiac output and cardiac work. The decrease in cardiac output relative to that in blood pressure suggests that the blood pressure reduction was largely due to the decrease in cardiac output. There was a decrease in coronary flow accompanied by an increase in myocardial oxygen extraction of such Degrees that cardiac oxygen consumption remained unchanged. Since myocardial oxygen consumption remained unchanged despite the decrease in cardiac work the calculated cardiac efficiency was decreased.

The systemic and coronary hemodynamic effects of synthetic bradykinin.

Abstract 1. The systemic and coronary hemodynamic effects of bradykinin have been studied during its infusion into anesthetized dogs. 2. The administration of bradykinin is associated with decreased peripheral, pulmonary, and coronary vascular resistance, accompanied by systemic arterial hypotension. 3. Cardiac output increased, and coronary blood flow increased in those animals with a normal or low resting coronary flow and decreased in those with high resting coronary blood flow. 4. The depletion of catecholamine, through the administration of reserpine, does not change the response basically, although it is modified slightly.

THE SYSTEMIC AND CORONARY HEMODYNAMIC EFFECTS OF DIAZOXIDE.

Abstract 1. 1. Hemodynamic studies, including the determination of cardiac output and coronary blood flow, have been made before and after the intravenous administration of diazoxide to anesthetized intact dogs and unanesthetized man. The response was essentially the same in the dog and in man. 2. 2. Administration of this agent intravenously was accompanied by an acute reduction in peripheral, total pulmonary, and coronary resistances, with a decrease in systemic and pulmonary arterial pressures and an increase in cardiac output and coronary blood flow. 3. 3. Coronary sinus oxygen content increased, with the per cent increase in coronary blood flow significantly greater than the change in cardiac rate, left ventricular work, and left ventricular oxygen consumption. 4. 4. The acute hemodynamic effects of diazoxide in control animals are not significantly different from the effects in animals pretreated with chlorothiazide or small doses of reserpine. 5. 5. Although both diazoxide and chlorothiazide are benzothiadiazine derivatives, their acute hemodynamic effects differ greatly.

Comparison of Systemic and Coronary Hemodynamics in the Normal Human Male and Female

Coronary and systemic hemodynamics were compared in 15 normal men and 15 normal women. Systemic hemodynamics were very similar. The women had 26.5 per cent greater coronary flow and 19.6 per cent more oxygen consumption/100 Gm. of left ventricular myocardium. Their calculated coronary vascular resistance was 35 per cent less. Significant negative correlations between coronary flow and calculated heart weight, and between cardiac oxygen consumption and calculated heart weight, as well as between coronary flow and hematocrit probably explain the differences in part. Whether hormonal or anatomic differences are also significant is not known.

Hemodynamics of Mitral Stenosis with Special Reference to Coronary Blood Flow and Myocardial Oxygen Consumption

A LTHOUGH there are excellent articles concerning the clinical and hemodynamic features of mitral stenosis,1-3 information concerning the coronary blood flow and the myocardial metabolism of oxygen and carbon dioxide in such subjects is inadequate. This report describes hemodynamic observations in 20 female subjects with mitral stenosis who underwent cardiac catheterization with determinations of the cardiac output and coronary blood flow.

The Effect of Hexamethonium upon Cerebral Blood Flow and Metabolism in Patients with Premalignant and Malignant Hypertension

In 13 patients with grade III or grade IV hypertensive retinopathy the effect of intramuscular hexamethonium bromide on cerebral circulation and metabolism has been studied. The results have been compared with Dewars study of hexamethonium in less severe hypertensive patients and with Ketys results following differential spinal sympathetic block. Sixty minutes after intramuscular hexamethonium, mean arterial blood pressure fell 39 per cent, cerebral vascular resistance was reduced 29 per cent, and cerebral blood flow decreased 16 per cent. Cerebral oxygen consumption was maintained at the expense of a reduction in cerebral venous oxygen saturation.

Familial aspects of congenital heart disease

Abstract Nineteen families with two or more cases of congenital heart disease have been presented. It is concluded that hereditary factors play a role in the etiology of congenital heart disease, but their relative importance remain to be determined. In some families the incidence of congenital heart disease is very impressive.