George P. Robb

Evaluation of type and degree of change in postexercise electrocardiogram in detecting coronary artery disease.

Summary Ischemic ST segment depression after exercise is due usually to coronary atherosclerosis and insufficiency. Our data suggest that type and degree of ischemic ST segment depression after exercise reflects the severity of the coronary disease. The results of this investigation indicate also that ST junction depression is a normal response to exercise.

The velocity of pulmonary and peripheral venous blood flow and related aspects of the circulation in cardiovascular disease

Abstract 1. 1. Sodium cyanide in amounts sufficient to produce adequate stimulation of respiration can safely be administered to patients with cardiovascular disease. The average effective dosage is approximately three-fourths that required by normal subjects: 5.2 mg., or 2.6 c.c. of a 2 per cent solution, which is equivalent to 0.084 mg. per kilogram. The fact that the respiratory center is hyperirritable to cyanide in the presence of circulatory failure makes this method particularly suitable for the measurement of the velocity of blood flow in heart disease. No untoward results have followed its administration to patients with circulatory failure when given in amounts sufficient to produce marked stimulation of respiration. 2. 2. The curve representing respiratory response following administration of cyanide reveals the character of the pulmonary blood flow in heart disease. 3. 3. Comparative measurements of the circulation time obtained with the cyanide, radium emanation, and vital red methods reveal that results obtained with the cyanide method are reliable indices of the velocity of blood flow in the pulmonary and peripheral venous circulations. As a rule the prolongation of the circulation time paralleled the severity of circulatory failure. 4. 4. Marked reduction in the vital capacity of the lungs may develop at an early stage of circulatory failure when the velocity of pulmonary blood flow shows slight or no decrease and the peripheral venous circulation, as well as the venous pressure, is normal. 5. 5. In a group of patients with arterial hypertension and intense dyspnea, evidence was obtained that pulmonary vascular hypertension existed without retardation of the blood flow through the lungs. 6. 6. In a group of patients with disability due to hypertensive, syphilitic, or arteriosclerotic cardiovascular disease, disturbances of the pulmonary circulation were associated with normal peripheral venous circulation. 7. 7. Owing to the numerous factors influencing hemodynamics, no strict correlation existed between clinical manifestations and the aspects of the circulation studied. Statistically, progressive reduction in the vital capacity and in the velocity of the pulmonary and peripheral venous blood flow, as well as an elevation of the venous pressure, are associated with an increasing degree of disability.1. 1. Sodium cyanide in amounts sufficient to produce adequate stimulation of respiration can safely be administered to patients with cardiovascular disease. The average effective dosage is approximately three-fourths that required by normal subjects: 5.2 mg., or 2.6 c.c. of a 2 per cent solution, which is equivalent to 0.084 mg. per kilogram. The fact that the respiratory center is hyperirritable to cyanide in the presence of circulatory failure makes this method particularly suitable for the measurement of the velocity of blood flow in heart disease. No untoward results have followed its administration to patients with circulatory failure when given in amounts sufficient to produce marked stimulation of respiration. 2. 2. The curve representing respiratory response following administration of cyanide reveals the character of the pulmonary blood flow in heart disease. 3. 3. Comparative measurements of the circulation time obtained with the cyanide, radium emanation, and vital red methods reveal that results obtained with the cyanide method are reliable indices of the velocity of blood flow in the pulmonary and peripheral venous circulations. As a rule the prolongation of the circulation time paralleled the severity of circulatory failure. 4. 4. Marked reduction in the vital capacity of the lungs may develop at an early stage of circulatory failure when the velocity of pulmonary blood flow shows slight or no decrease and the peripheral venous circulation, as well as the venous pressure, is normal. 5. 5. In a group of patients with arterial hypertension and intense dyspnea, evidence was obtained that pulmonary vascular hypertension existed without retardation of the blood flow through the lungs. 6. 6. In a group of patients with disability due to hypertensive, syphilitic, or arteriosclerotic cardiovascular disease, disturbances of the pulmonary circulation were associated with normal peripheral venous circulation. 7. 7. Owing to the numerous factors influencing hemodynamics, no strict correlation existed between clinical manifestations and the aspects of the circulation studied. Statistically, progressive reduction in the vital capacity and in the velocity of the pulmonary and peripheral venous blood flow, as well as an elevation of the venous pressure, are associated with an increasing degree of disability.

VISUALIZATION OF THE CHAMBERS OF THE HEART AND THE THORACIC BLOOD VESSELS IN PULMONARY HEART DISEASE; A CASE STUDY

Excerpt Pulmonary heart disease, orcor pulmonale, has long been known as a disorder which tends to develop in the course of certain chronic pulmonary diseases. Emphysema1, 2, 3and pulmonary fibrosi...

The Dilator Effect of Histamine on the Cerebral Vessels in Man.

Direct evidence as to whether or not the cerebral vessels in man possess vasomotor play is still lacking. The following observations on patients indicate that the arterioles, capillaries, and venules of the human brain respond with prompt dilatation to histamine. Following the intravenous administration of an average dose of 0.07 mg. (0.7 cc. of a solution of 1:10,000) of histamine phosphate the spinal fluid pressure showed a marked rise. The onset of this rise occurred about simultaneously with the circulation time of the injected histamine. During and slightly after the rise of the spinal fluid pressure the excursions of the oscillatory pulsation of the spinal fluid were greatly increased, although there was no demonstrable rise in the simultaneously registered arterial or venous blood pressure. Coincident with these objective changes there was a sensation of throbbing and pressure in the head. A small amount of histamine phosphate administered intravenously, when the hemisphere was exposed for the purpose of removal of tumor, caused a prompt bulging of the brain, a distinctly increased cerebral pulsation, and a visible bright flush of the brain surface. These changes, just as other bodily responses following the single intravenous dose, lasted but 0.5 to 3 minutes. Forbes, Wolf and Cobb have observed a similar behaviour of the small pial vessels of the cat. Adult subjects tolerated well the continuous intravenous administration of 0.05 to 0.1 mg. of histamine phosphate per minute of a solution of 1:10,000. The oxygen and carbon dioxide content of the arterial blood flowing to, and the venous blood returning from the brain was measured. It was observed that while the arterial blood during the administration of histamine showed an average increase of 8% in the oxygen content, because of increased concentration of the blood; the oxygen content of the blood obtained from the internal jugular vein showed an average rise of 20% over the value found before the injection of histamine. During identical experimental conditions the average increase in the oxygen content of the blood obtained from the external jugular vein was 12%, and that from the basilic vein 24%. The average decrease of the carbon dioxide content of the blood obtained from the internal jugular vein was 9%.

Modification of the electrocardiogram of myocardial infarction by anomalous atrioventricular excitation; Wolff-Parkinson-White syndrome.

Abstract The difficulty in occasional instances of differentiating myocardial infarction from anomalous atrioventricular excitation (Wolff-Parkinson-White syndrome) has been noted by Levine and Beeson, 1 Palatucci and Knighton, 2 Eichert, 3 and Missal, Wood, and Leo. 4 The paroxysmal tachycardia which occurs so regularly with anomalous excitation may produce chest discomfort which may be mistaken for the pain of infarction, and the electrocardiogram of anomalous excitation may also cause confusion. Fischer, 5 Zoll and Sachs, 23 Goldbloom and Dumanis, 6 and Rinzler and Travell 24 have reported cases of the coexistence of the two conditions. In these cases electrocardiograms were not recorded during periods when the anomalous excitation reverted to normal excitation, so that there is no comparison between the two, and the effect of anomalous excitation on the electrocardiogram of myocardial infarction cannot be determined. In the case which is the basis of the present discussion there is definite evidence of the coexistence of the two conditions, and electrocardiograms were recorded shortly after infarction showing both normal and anomalous excitation. These electrocardiograms reveal the fact that anomalous atrioventricular excitation may obscure some of the diagnostic electrocardiographic signs of infarction, in this case, the Q wave. During normal excitation the electrocardiograms showed the characteristic Q 2 and Q 3 of posterior wall infarction. At other times, however, during anomalous excitation the Q 2 and Q 3 were absent, and the initial portions of QRS 2 and QRS 3 were small R waves.

A Correlation of the Hemodynamics, Function, and Histologic Structure of the Kidney in Malignant Arterial Hypertension with Malignant Nephrosclerosis

Excerpt The correlation of the functional behavior and the structural characteristics of the blood vessels with the physiological units of the kidney is one of the most significant advances in the ...

Isolated dextrocardia, with diodrast studies

Abstract 1. 1. A case of congenital isolated dextrocardia, without “mirror-image” inversion of the chambers, but with signs of congenital heart disease and attacks of paroxysmal tachycardia is presented. 2. 2. The expected noninversion of the heart chambers was supported by diodrast and electrocardiographic studies. The “apex” of the heart was shown to be formed by the right (venous) ventricle. The left-sided aortic arch and superior vena cava were also demonstrated by diodrast visualization. 3. 3. The rarity of the long survival of the patient and of the attacks of paroxysmal tachycardia is noted.

A Visualization Study of Fibrothorax: Identification of the Cardiovascular Structures1,2

IN patients having massive pulmonary fibrosis, or “fibrothorax,” the conventional roentgenogram fails to reveal the essential features of the thoracic cardiovascular system. However, visualization of these structures is now possible, for, recently, we have developed a method for the visualization of the chambers of the heart, the pulmonary circulation, and the, great vessels (1, 2), and have reported examples of its value in the normal individual (3) and in patients having heart (4) and lung (5) disease. It has been possible to see the cavity and wall of each chamber, the interventricular septum, the pulmonic and aortic valves, the pulmonary artery and wall, the entire pulmonary circulation, and the thoracic aorta with its wall and the branches from the arch. In this paper we wish to illustrate the value of this method in a patient in whom there was displacement and obscuring of the heart by pulmonary and pleural fibrosis and to show that it is now possible to visualize the cardiovascular structures as we...

Effect of Digitalis and Rest on Pulmonary and Peripheral Circulation in Patients with Circulatory Failure Caused by Heart Disease

This study was undertaken to shed further light on the mechanism of circulatory failure caused by heart disease and on the circulatory changes that follow administration of large therapeutic doses of digitalis, and rest. Weiss and Ellis 1 observed the effect of digitalis on the volume and velocity of blood flow and other aspects of the circulation after repeated control observations in patients with rheumatic heart disease and with compensated circulation at rest. In this study such repeated control observations on the aspects of the circulation measured, because of the clinical condition of the patients and of the methods used, were not feasible. A definite separation of the changes due to digitalis effect and rest between determinations, therefore, cannot be made, but the arrangement of the observations was similar to those used in the treatment of cardiac patients. To ascertain a possible correlation between the pulmonary circulation and ventilatory function, in some of the cases measurements of different components of the lung volume were also performed simultaneously with the circulatory observations. The following aspects of the circulation were studied simultaneously before and after digitalis: (1) electrocardiogram; (2) the degree of orthopnea; (3) arterial blood pressure; (4) venous pressure with the method of Moritz and Tabora 2 ; (5) cardiac minute volume output with the method of Moore, Kinsman, Hamilton, and Spurling 3 ; (6) the peripheral and pulmonary velocity of the blood flow according to the method of Weiss and Robb 4 ; (7) blood volume according to the method of Keith, Rowntree and Geraghty 5 ; (8) lung volume with the method of Van Slyke and Binger 6 ; (9) oxygen and carbon dioxide content of the blood samples obtained from the femoral artery and vein.