ISSN:0009-7322    

出版商:OVID    

年代:1950

数据来源: OVID

摘要:

An electronic circuit capable of integrating the electrocardiogram is described. The net areas of the QRS complex, the T wave and of the entire ventricular complex, QRS-T, in the standard leads may be estimated by measurement of the length of two vertical lines in each of the integrated records. The manifest areas of QRS, T and the gradient (QRS-T) with the orientation of these vectors are easily calculated from the data. An example of an integrated electrocardiogram is reproduced, and the procedure for estimation of the gradient is presented.

ISSN:0009-7322    

出版商:OVID    

年代:1950

数据来源: OVID

摘要:

Electrical records were made from the interior of the right heart and attached vessels in 14 normal subjects. Technics differed somewhat from those previously reported in that simultaneously recording string galvanometers were used exclusively, and tracings were made whenever the catheter-electrode was moved within the heart. Previously unreported large positive QRS deflections were found in records from the lower part of the right atrium, from the pulmonary artery, and in two instances from within the right ventricle itself close to the base. The possible anatomical origin of these is discussed.

ISSN:0009-7322    

出版商:OVID    

年代:1950

数据来源: OVID

摘要:

Curves which represent bundle branch block can usually be identified. More important are those which represent peri-infarction block. Multiple unipolar leads enable identification of the latter from the former, which they may closely resemble in the limb leads, and from intraventricular block of other types. Criteria and examples of peri-infarction block are presented and an incidence and explanation are offered.

ISSN:0009-7322    

出版商:OVID    

年代:1950

数据来源: OVID

摘要:

The technic of endocardial electrocardiography has been useful in applying certain basic concepts to the interpretation of an electrocardiogram. One of the earliest intra-auricular records, obtained in 1944, is here analyzed in detail. It led to a reaffirmation of the dipole concept of cardiac excitation. A number of selected auricular electrocardiograms recorded by simultaneous tracings from the chestwall and the esophagus demonstrate the direct clinical usefulness of the theoretic postulates.

ISSN:0009-7322    

出版商:OVID    

年代:1950

数据来源: OVID

摘要:

Two parallel researches in progress at the Brigham Hospital, one an investigation of intracardiac electrography in general, the other a long-term study of heart muscle metabolism with the aid of the venous catheter, converge, resulting in the interesting practical and theoretical findings reported here. The authors show how the electrogram may help establish the position of the catheter in the coronary venous system and indicate the type of potential variations recorded in the coronary sinus, in its continuation, the great cardiac vein, and in its tributary, the middle cardiac vein.

ISSN:0009-7322    

出版商:OVID    

年代:1950

数据来源: OVID

摘要:

The electrocardiograms of patients in whom myocardial infarction was excluded at autopsy are presented to bring out (1) the following features of left bundle branch block suggesting anteroseptal infarction—QS or qrS patterns in leads from the right precordium or localized to intermediate leads and/or cove plane inversion of the T waves near the transitional zone; (2) the following features of right bundle branch block suggesting infarction—pseudo Q waves, elevated RS-T segments and inverted T waves in right precordial leads, prominent Q waves in leads from the left precordium.

ISSN:0009-7322    

出版商:OVID    

年代:1950

数据来源: OVID

摘要:

The electrocardiograms of patients in whom myocardial infarction was excluded at autopsy are presented to bring out (1) differentiation of patterns due to subendocardial ischemia or hypopotassemia from those due to subendocardial infarction; (2) differentiation of cove-plane T inversion associated with subepicardial myocarditis or ischemia from that accompanying myocardial infraction; (3) errors resulting from attempts to draw diagnostic inferences from the registraition of prominent Q waves and/or cove negative T waves in ectopic beats or tachycardias.

ISSN:0009-7322    

出版商:OVID    

年代:1950

数据来源: OVID

摘要:

The present role of the electrocardiogram in clinical medicine is discussed and its limitations as a diagnostic tool are pointed out. Its particular usefulness in the analysis of arrhythmias and the value of certain specific empirically derived patterns are discussed. The misuse of the term "unipolar" is explained, the actual conditions present being only crude approximations of the assumptions upon which the equilateral triangle theory rests. The role of multiple V chest leads and the aV limb leads in clinical electrocardiography is outlined. A brief explanation of stereovectorcardiography and the great promise it holds for the future is presented.

ISSN:0009-7322    

出版商:OVID    

年代:1950

数据来源: OVID

摘要:

Modifications in recorder standardization are required to correct inherent scalar differences among potential differences measured in a given electrocardiographic reference frame. In the frontal plane, agreement between the resultant vectors calculated from unipolar limb lead measurements and from standard lead measurements can be obtained by standardizing the galvanometer for recording the unipolar limb lead potentials at √3 cm. per millivolt. A method for calculating this "standardizing factor" and similar factors for other reference frames is presented and applied to calculations for the equilateral tetrahedron, the isosceles tetrahedron, and the cube.

ISSN:0009-7322    

出版商:OVID    

年代:1950

数据来源: OVID