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Discusses the diagnostic approaches of coronary artery disease. Tests utilized to examine the capability of electrocardiogram to detect latent impairment of the coronary circulation; Efficiency of exercise electrocardiogram test in the detection and monitoring of coronary heart disease; Capability of the test to reflect the behavior of an intact circulation during stress.

1. The effect of bowel function on the peripheral circulation was investigated in a group of normal and constipated subjects by observing the changes in arterial and venous pressure as well as in segmental blood flow. A study was also made of the effects of controlled straining on segmental blood flow, digital blood flow and peripheral vascular resistance. 2. The peripheral circulation is subjected to a variety of stresses during normal bowel function release of the strain there was a transient return of the blood flow toward control levels followed by a second diminution, after which a vasodilation occurred before the return of the resting state. In response to controlled straining efforts, the venous pressure rose proportionately to the magnitude of straining. 4. During controlled exertions, the digital blood flow and pulse volume showed a pattern of change similar to that of the segmental circulation. Again, a. vasoconstriction and a vasodilation were observed after the strain period. 5. Controlled straining efforts produced a marked rise in peripheral segmental and digital vascular resistance. The response was greater in the legs and toes than in the arms and fingers. This increased resistance terminated at the conclusion of the strain only to be followed by a sharp increase during the poststrain period. 6. Throughout the study, the fluctuations among the constipated group were of a greater magnitude and frequency than those observed among the normal subjects. This was a reflection of the greater and more profound straining efforts of the former group. 7. The implications of these findings with respect to the mobilization of peripheral thrombi and production of pulmonary embolism are discussed. The present findings emphasize the conclusion of our earlier study14 that, if tragic cardiovascular episodes associated with defecation are to be avoided, the immediate correction of constipation is of particular importance. [ABSTRACT FROM AUTHOR]

1. The effect of bowel straining on the cardiopulmonary system was studied in a group of normal and constipated subjects by observation of changes in the heart rate, electrocardiogram, heart sounds, pulmonary circulation and circulation time. 2. The presence of either a tachycardia or bradycardia occurring in connection with certain straining efforts of defecation as they affect the heart rate was confirmed. These alterations of the rate are reflexes principally associated with the Valsalva phenomenon. 3. The Valsalva maneuver initiated electrocardiographic changes in 2.5 per cent of the 209 healthy persons studied. These changes most often consisted of marked T-wave lowering and ST-segment depression. Other alterations included extrasystoles, partial heart block, slurring of the QRS-complex and T-P fusion. It was concluded that reduced coronary perfusion was the most likely causative factor for the abnormalities described. 4. The effect of bowel straining on heart sounds and murmurs appears to conform to the known dynamic results of straining at stool and the physiologic mechanism accountable for the acoustic phenomena. 5. The entire pulmonary circulation is a low tension system, indicating large channels of flow with low resistance. The effects of straining on the venous return to the heart from the pulmonary circuit, as well as the results of straining on pulmonary arterial, left atrial and pulmonary ‘capillary’ pressures are discussed and related to the four phases into which the circulatory system's response to the Valsalva maneuver has been divided. 6. The effect of straining on the circulation time was studied in terms of strains of periods shorter than 10 seconds, along with the possible additive effects of individual strains of less than 6 seconds' duration would grossly affect the circulation time. However, sustained efforts exerted at pressures in excess of 10 mm Hg for more than 6 or 8 seconds would prolong circulation time in rough approximation to the duration of the strain. 7. The straining efforts in constipated individuals are greater and more profound than in normal individuals. The implication of this fact with respect to the cardiopulmonary dynamics of bowel function is discussed and the hazards involved are indicated. 8. The present findings emphasize the conclusion that physiologic changes after straining at stool may result in serious consequences, and, if tragic episodes are to be avoided, the immediate correction of constipation assumes special significance for persons who suffer from serious organic heart disease. [ABSTRACT FROM AUTHOR]

1. In normal dogs and monkeys, the Valsalva maneuver was found to produce a marked fall in carotid blood pressure with a simultaneous rise in jugular vein and cerebrospinal fluid pressures, parallelling the rise in intrathoracic pressure. In two human subjects without cerebrovascular disease, performance of the Vulsalva maneuver resulted in a brief rise in brachial and carotid arterial pressure, followed rapidly by a precipitous fall. 2. Electroencephalographic as well as angiographic studies in normal dogs demonstrated that performance of the Valsalva maneuver produces circulatory stasis sufficient to result in anoxic changes in the cortical cells. 3. It is emphasized that a transient fall in cerebral blood pressure, resulting in fluctuations in cerebral oxygen supply, may be particularly hazardous to patients with existent cerebrovascular disease. In such individuals, reduction of stresses to the cerebral circulation is of utmost importance. Since straining at stool is perhaps the most common source of such circulatory stress, and since the magnitude and duration of straining efforts are greatest among constipated patients, the correction of constipation becomes an essential part of the therapeutic regimen of patients with cerebrovascular or vascular disease. [ABSTRACT FROM AUTHOR]

1. The physiology of defecation is discussed and the contribution of intrathoracic, intraabdominal and intestinal intraluminal pressures to the straining forces of bowel function is explored. 2. Exertion at stool may effect an intraabdominal pressure increase of up to 200 mm Kg and also tends to produce excessive intraluminal and intrathoracic pressures. Various techniques for recording intraluminal pressures are described. 3. The duration and magnitude of elevated intrathoracic pressures during straining episodes in normal and constipated subjects were studied and classified according to the criteria of the Valsalva maneuver. It was found that use of the lied pan (in normal individual) and the presence of constipation markedly increase the frequency, intensity and duration of straining during defecation. More than half of the efforts of the constipated group met the Valsalva criteria, whereas only 12 per cent of the exertions of the normal group fell into this category. 4. The use of a constipation corrective reduced the number of strains exceeding 40 mm Hg from a pretreatment level of 93.9 per cent ot 38.8 per rent, and the incidence of exertions lasting longer than 8 seconds was reduced from 03.3 per cent before therapy to 12.2 per cent after therapy. The use of such agents, therefore, is indicated to reduce the incidence of these stressor effects. [ABSTRACT FROM AUTHOR]

The proposed mechanisms of the symptomology for Raynaud's disease and Raynaud's phenomenon have been reviewed, and these have been extended to include the role of serotonin in both the initiation and propagation of the digital symptoms. [ABSTRACT FROM AUTHOR]

Examines the efficacy of quinidine in the treatment of cardiovascular diseases. Contraindication to the use of the drug due to its toxic manifestations; Analysis on the allergic and idiosyncratic reaction of the drug; Response of cardiac patients to cardiovascular therapy using quinidine.

1. A series of investigations utilizing several hundred patient observations wore carried out to determine the effects of defecation on circulatory function in presumably normal individuals and persons with chronic constipation. 2. It appears that during bowel function of apparently normal individuals, approximately 12 per cent of the straining episodes are of sufficient intensity and duration to satisfy the accepted criteria for the Valsalva maneuver, and that by substituting a bedpan for the commode, this incidence is more than doubled (28.0 per cent). Constipation, it may be noted, increases this frequency approximately fivefold (57.9 per cent). From the results of research presently underway, the use of a constipation corrective, Senokot, favorably modifies the magnitude and duration of straining among constipated individuals. 3. The established sequential changes in blood pressure of the Valsalva maneuver were found to occur during defecation in response to those strains meeting this criteria. While the height of the initial blood pressure rise was roughly proportional to the intensity of the effort in both groups, the constipated group had twice as many peaks above 60 mm Hg than did the normal group and conversely, the normals had three times as many peaks below 20 mm Hg as did the constipated series. 4. The peaks of the phase IV overshoot were not found to be related to the height of the original straining pressures exerted. The distribution of these peaks was comparable in both groups, when they occurred. 5. The Valsalva maneuver initiated electrocardiographic changes in approximately 20 JXT cent of the normal subjects studied. These changes included (1) ST depression, (2) flattening of the T wave, (3) poststraining arrhythmia, and (4) the reversal of a previously al)normal T wave to one which became fiat to upright. These abnormalities are generally associated with physiologic myocardial insufficiency. No significant abnormalities of the electrocardiogram were detected in the remaining 80.4 per cent of the over-all group performing the Valsalva maneuver. 6. The presence of either a tachycardia or a bradycardia occurring in connection with certain of the straining efforts of defecation was confirmed. These alterations of the rate arc reflexes principally associated with the Valsalva phenomenon. 7. It becomes apparent, therefore, that the physician must seriously consider the volatile effects and potential hazards of .stool-straining in his cardiac patients. Our data indicates that physiologic changes following straining at stool may result in serious consequences, and if tragic episodes are to be avoided, the immediate correction of constipation becomes of special importance to the patient with cardiovascular disease. [ABSTRACT FROM AUTHOR]