John R. Braunstein

Transmural ventricular pressures in experimental cardiac tamponade.

Experimental cardiac tamponade was produced in open-chest dogs. Left and right ventricular systolic pressures fell when intrapericardial pressure was increased only a few millimeters of mercury. Negative diastolic transmural pressures of 1 to 6 mm. Hg developed in the left ventricle and negative diastolic transmural pressures of 2 to 8.5 mm. Hg developed in the right ventricle. In some instances the period of right ventricular systolic ejection was greatly abbreviated at higher levels of intrapericardial pressure.

Study of High Frequency Components in Electrocardiogram by Power Spectrum Analysis

A method has been developed for recording the power spectrum of the hearts electromotive force for the time interval corresponding to the QRS complex of the conventional electrocardiogram. Standards for healthy, young normals have been established. No significant change was noted in a group of healthy, middle-aged normals without heart disease. Three different patterns, however, were found for patients with ischemic heart disease, with and without evidence of infarction.

The Effect of Meals on the Electrocardiogram and the Ballistocardiogram in Patients with Angina Pectoris

The effect of meals on the electrocardiogram and the ballistocardiogram was studied in 59 patients with angina of effort. Approximately one-fourth of the group showed a 0.5 to 1.0 mm. depression of the S-T segment, while the normal controls did not show this change. Premature ventricular contractions and inversion of the T wave were found more frequently in patients with angina following meals than in normal individuals. The patients with angina were unable to increase the cardiac output significantly following meals as compared to normal individuals. It is suggestetd that these findings may prove to be of value in evaluating cardiac function in patients with angina.

Anatomic and Electrocardiographic Position of the Heart

Thirty-four patients were studied by electrocardiogram for electrical position of the heart, and by x-ray and angiocardiogram for anatomic position of the heart. A significant association between electrocardiographic and anatomic positions of the heart was found insofar as rotation about the anteroposterior and longitudinal axes is concerned. No association between electrocardiographic and anatomic positions was found with regard to rotation about the transverse axis.

A Proposed Nomenclature and Convention for Recording the Ballistocardiogram

When this paper was submitted to the editors of CIRCULATION it called to their attention the desirability of enlarging the work that Dr. Braunstein has begun in the following paper. Accordingly, Dr. Howard Sprague, President of the American Heart Association appointed a committee to study the field and to make recommendations leading toward both a uniform terminology and uniform methods of presenting data secured by ballistocardiographs, and Dr. Braunstein kindly consented to withhold the publication of his paper until the committee was ready to report. This committee has now approved the terminology suggested by Dr. Braunstein and, in a first report, which immediately follows Dr. Braunsteins paper, makes other recommendations pertaining to terminology and conventions for parts of the field not covered by Dr. Braunsteins paper.

A Study in Frontal Plane Vectorballistocardiography

Frontal plane ballistocardiograms obtained from 10 normal subjects were analyzed and compared with abnormal records obtained from patients with known cardiovascular disease. The normal vector loop is described, and the importance of the transverse ballistocardiogram is discussed. It is suggested that the orientation of the J loop may be related to the anatomic position of the heart. No such relationship was noted with the frontal plane H, I or K vector loops.

The Ballistocardiogram in a Free Clinic

Of 240 patients consecutively admitted to the Cardiac Clinic of the Cincinnati General Hospital, and on whom a clinical diagnosis of heart disease was ultimately established, 204 had a ballistocardiogram taken and either an electrocardiogram, a six-foot chest plate or both of the latter two. The ballistocardiogram was evaluated (1) in terms of abnormality of pattern and (2) in degree of deviation from normal initial cardiac force. Frequency of abnormality in the various technics is presented for the group as a whole as well as for several etiologic groups. It is concluded that for a population of this kind the frequency of abnormality in the ballistocardiogram and electrocardiogram is essentially the same, whereas it is somewhat less in the chest plate.