Harry L. Jaffe

Spatial vectorcardiography: Technique for the simultaneous recording of the frontal, sagittal, and horizontal projections. I

Abstract A technique for the simultaneous recording of a frontal, sagittal, and horizontal vectorcardiogram is described. The geometric arrangement selected for electrode placement is that of a cube. The reasons for preferring the cube arrangement to the equilateral tetrahedron are discussed.

Bundle branch and intraventricular block in acute coronary artery occlusion

Abstract 1. 1. Intraventricular block, including bundle branch block, was present in 15 per cent of 375 cases of acute coronary artery occlusion. 2. 2. Patients in this group were older than controls and presented clinical and pathologic evidence of severe heart disease. Congestive heart failure, antecedent hypertension, cardiac enlargement and evidence of previous attacks were the rule. 3. 3. The conduction defect was usually observed on the first day and was usually permanent. In six patients it was transient. 4. 4. Intraventricular or bundle branch block could not be diagnosed clinically since there were no specific symptoms or physical signs. Gallop rhythm was present in 60 per cent of the cases, but was probably due to the associated wevere heart failure. 5. 5. Left bundle branch block occurred in 51 per cent of the group, typical or atypical right bundle branch block in 28 per cent and intraventricular block in 21 per cent. The configuration of the ventricular complexes as well as the axis deviation often varied in serial records. 6. 6. In the presence of intraventricular block characteristic electrocardiographic signs of myocardial infarction failed to appear in one-third of the cases. 7. 7. The precordial lead may be of diagnostic importance, for progressive S-T and T-wave changes may occur only in this lead. Absence or marked diminution in the initial positive deflection in this lead is usually due to anterior wall infarction even when bundle branch block is present, although occasionally the latter alone is the cause. 8. 8. Intraventricular block was often associated with impaired auriculoventricular conduction. Other arrhythmias were not more common than in coronary occlusion in general. 9. 9. The sudden appearance of defective intraventricular conduction should suggest recent coronary occlusion. Since bundle branch or intraventricular block following coronary occlusion is usually permanent, it may be the only evidence that the patient has suffered a coronary occlusion in the past. Repeated attacks of coronary occlusion may result in a progressive increase in the QRS duration. 10. 10. The presence of defective intraventricular conduction in coronary occlusion adds to the seriousness of the prognosis, the mortality rate being 42 per cent. The more severe the conduction defect was, the higher the mortality rate, but there was no correlation with the type of block. 11. 11. The anatomical basis for the conduction defect was septal infarction, which was present in four-fifths of the hearts. 12. 12. Correlation between the vessels occluded or the location of the septal infarct and the type of conduction defect could not be made; occlusion of the right coronary artery was as frequent as that of the left and anterior infarction was as common as posterior infarction, regardless of the type of block. 13. 13. The persistence of normal conduction in many cases with septal infarction was attributed mainly to the presence of adequate collateral circulation in the septum. 14. 14. Transient bundle branch block was probably due to anoxemia resulting from shock, tachycardia, and heart failure. 15. 15. The vagus nerve probably played no role in bundle branch block since the latter was not affected by the injection of atropine. 16. 16. The relation between cardiac enlargement and bundle branch block was discussed, and the influence on the electrocardiogram of cardiac enlargement and bundle branch involvement contrasted. 17. 17. The treatment is that of coronary occlusion in general, with special attention to heart failure. The value of aminophyllin and oxygen was emphasized. Quinidine and digitalis should be used only when there is persistent rapid ventricular rate with failure.

DISTURBANCES OF RATE AND RHYTHM IN ACUTE CORONARY ARTERY THROMBOSIS

Excerpt INTRODUCTION Investigators1-5during the nineteenth century observed that ligation of the coronary arteries in animals very frequently produced cardiac arrhythmias either transient or severe...

The treatment and the immediate prognosis of coronary artery thrombosis (267 attacks)

Abstract 1. 1. Two hundred and forty-three patients suffering from coronary artery thrombosis were treated by a low calorie diet and prolonged rest in bed. Digitalis, adrenalin, or nitrites were not used. 2. 2. The mortality rate in 267 attacks was 16.5 per cent; in first attacks only 8 per cent. Most patients survive an initial attack of coronary thrombosis. Almost one-half of our patients had suffered one or more previous attacks. 3. 3. Coronary thrombosis is not uncommon in women. The ratio of men to women was 3 to 1. It occurs not infrequently in the fourth and fifth decades and the prognosis in these is better than in the older age groups. The average age in our series was fifty-four years. 4. 4. Hypertension, which preceded the attack in 66 per cent of cases, did not directly influence the prognosis. When coronary thrombosis occurs in women, hypertension or diabetes is usually present. 5. 5. Infarction of the anterior and posterior surface of the left ventricle occurs with equal frequency; there is no difference in prognosis. 6. 6. Irregularities of the heart developing during an attack were transitory in most cases and required no specific treatment. 7. 7. Evidence is given that the good results reported in this series may be attributed in part to the undernutrition therapy which eliminates gastrocardiac reflexes, minimizes the rise in metabolism and cardiac output which usually follows a meal, and gradually lowers the basal metabolic rate. This effects a decrease in pulse rate and blood pressure, and so a diminution in the work of the heart. 8. 8. No ill effects were observed following the use of the low caloric diet. 9. 9. Instances of coronary artery thrombosis occur which are inevitably fatal because of the size of one or several simultaneous infarctions or because of the severe degree of involvement of all the coronary vessels. From this series of cases, however, it appears that in the main the prognosis of an attack is hopeful and, indeed, death in the first attack is infrequent.

Computer diagnosis of electrocardiograms. IV. A computer program for contour analysis with clinical results of rhythm and contour interpretation

Abstract The logic for the contour analysis programs and the results of a comparison of computer and physician diagnosis for over two thousand cases are described. A detailed breakdown of the patient population and nature of the errors made by the program is given. The effectiveness of the program as a screening tool is also considered.

The Two-Step Exercise Electrocardiogram A Double-Blind Evaluation of Its Use in the Diagnosis of Angina Pectoris

A double-blind study was made to evaluate the two-step exercise electrocardiographic test (Master) as a means of differentiating between anginal and nonanginal chest pain in 100 consecutive patients. A high percentage of false-positive results in nonanginal cases and a number of false negatives in anginal cases greatly impaired the usefulness of the test for this purpose. When Masters criterion of an ST depression of 0.5 mm. or more was employed, there were 39 per cent false positives and 12 per cent false negatives. Stricter criteria progressively diminished the number of false positives, but resulted in increasing numbers of false negatives. Even if 1 mm. or more of ST depression was required, there were 8 per cent false positives and 43 per cent false negatives. There were no false positives only when the ST segment was depressed 2 mm. or more. Although an ischemic type of ST depression may be more significant for angina pectoris than the J type, in our series ischemic ST depressions also occurred more frequently than the J type in false-positive tests in nonanginal patients. The new criteria of Master and Rosenfeld were not more satisfactory than the previous criteria recommended. There are relatively few cases in which an objective two-step test is necessary to aid in the differentiation of anginal and nonanginal pain, since an unequivocal diagnosis of angina pectoris or nonanginal pain was made in 86 per cent of cases independently by at least two observers, on the basis of a single interview, and since this percentage could undoubtedly have been increased by further interviews concerning the effect of effort and of nitroglycerin. Insofar as confirmation of a clinical diagnosis of angina pectoris by an objective exercise test is desirable, an ST-segment depression of at least 1 mm. usually offers such confirmation. However, this degree of ST-segment depression is often absent in unequivocal cases of angina pectoris and conversely may be occasionally present in patients with nonanginal pain.

The course of the blood pressure before, during, and after coronary occlusion

Abstract The course of the blood pressure before, during, and after the attack has been analyzed in five hundred thirty-eight cases of coronary occlusion. The incidence of hypertension increased with age. The blood pressure fell to some extent in every case, although in a few cases the fall was slight. A transitory rise in pressure occurred infrequently at the onset of the attack. A rapid fall was somewhat more common than a gradual one. Occasionally the fall did not occur until after a week. The lowest pressure was usually reached between the twelfth and twentieth days. In some cases the initial fall was soon followed by a temporary or permanent rise in pressure. The trend of the blood pressure was similar in the hypertensive and nonhypertensive groups, although a rapid fall was more common among the nonhypertensive patients who died. The systolic blood pressure rarely fell below 90 mm. in the hypertensive group, but this was common in the nonhypertensive group. When the pressure fell below 80 the patient usually died. In almost one-fifth of patients with a previous pressure of 200 mm. or more the pressure did not fall below 150 mm. Two-thirds of the hypertensive patients regained a hypertensive level; in half of these this took place before discharge from the hospital, and, in the remaining half, usually within one or two years. The height of the blood pressure after the attack did not significantly influence the future course of the patient with respect to subsequent angina pectoris, heart failure, coronary occlusion, or death.

Acute coronary insufficiency: its differential diagnosis and treatment.

Excerpt As the years pass, the known incidence of coronary disease continues to rise. Today, about one of every three men over the age of 35 and the vast majority of men over 50 have a significant ...

PREMONITORY SYMPTOMS OF ACUTE CORONARY OCCLUSION; A STUDY OF 260 CASES

Excerpt The symptoms of occlusion of the coronary artery are now well known, and the diagnosis of the acute attack is generally made with little difficulty. It is only recently, however, that atten...

Chest Leads in Normal Children.

Conclusion Positive T-waves at, or within the apex, which are abnormal findings in adults, are normal in children.