History Of The Digital Ballistocardiograph^®

The science of Ballistocardiography was conceived over a century ago and was studied extensively until the 1960’s¹. Originally Ballistocardiograph devices recorded movement caused by the percussive effects of the heart while the patient lay supine on a bed. The bed either contained an apparatus that would allow for the measurement of the motion generated by the heart’s percussive forces or a facilitating apparatus that was attached across the shin area of the legs. HFM derived considerable encouragement and guidance in the development of the dBG300^® from reviewing the classical ballistocardiography publications from the cardiology literature of the 1950s & 60s. These references include:

• Essays defining the physiological significance of Ballistocardiography²
• The interpretation and standardization of nomenclature of the BCG waveforms³
• An understanding of the physics involved in the process⁴

Enthusiasm for the development of a clinically applicable dBG300^® came from papers such as Isaac Starr’s study of the effects of nitro-glycerine on the BCG in patients with coronary artery disease⁵. Later publications, describing attempts to develop improved ballistocardiogram recording devices, indicated a broad interest in the cardiology community⁶.

Extensive work was completed between 1930 and 1960 by Isaac Starr using ballistocardiograph ballistocardiogram data to classify ballistocardiograph waveforms as normal, slightly abnormal, markedly abnormal and extremely abnormal⁷. Further research work was undertaken to categorize BCG waveforms with patients that had known clinical conditions such as hypertension, angina pectoris, congestive failure, rheumatic heart disease⁸. Eventually the science was accepted by the American Heart Association. However the ballistocardiograph device was large and cumbersome. Ballistocardiography was ultimately abandoned in the 1970s as new and emerging technologies including ultrasound and angiography eclipsed the BCG technology. HFM is applying modern accelerometer-based technology to revitalize the science of ballistocardiography.


Where The dBG300^® Fits In Cardiology

The dBG300^® represents a significant improvement compared with classical Ballistocardiograph technology that was offered to cardiologists both in the1950s. It will be used as part of the physician’s overall assessment of patients, either in a busy office practice or in the hospital. It provides information immediately to the physician during the patient’s visit. Physicians already have a range of relatively simple instruments to assess patients. The dBG300^® complements these and accurately provides timing events of the cardiac cycle without having to refer the patient for an echocardiogram. The information is immediately available and the patient is freed from having to return for another visit to see the physician. The dBG300^® offers physicians a simple and quick means of assessing patients safely and non-invasively at every visit. HFM believes that repeat assessments will reveal the relative changes in the heart’s performance. As a result the dBG300^® should eventually be used to assess the capability and the relative efficiency of the heart to pump blood at every patient visit.


References

1. Progress Towards a Physiological Cardiology; A Second Essay on the Ballistocardiogram, Isaac Starr,M.D. Annals of Internal Medicine Vol.63, No. 6 December 1965 pp. 1079 - 1105,
   
2. Proposals for Ballistocardiographic nomenclature and Conventions: Revised and Extended: Report of the Committee on Ballistocardiographic Terminology, Scarborough et al Circulation 1956; 14;435-450
   www.circ.ahajournals.org
   
3. Force, Work, and Power Ballistocardiography; Soon Kyu Suh, W H Cooper, W.H Frederick and E. E. Eddleman Jr.; American Journal of Cardiology, June 1958 pp. 726-735.
   
4. The Effect of Nitroglycerine on the Ballistocardiogram of Persons with and without Clinical Evidence of Coronary Heart Disease. Isaac Starr, Elaine Pedersen and Aldo N. Corbascio; Circulation 1955;12;588- 603.
   
5. Relationship between Seismocardiogram and Echocardiogram for Events in the Cardiac Cycle. Crow,
   Hannan, Jacobs, Hedquist and Salerno; Am J Noninvas. Cardiol 1994;8;39-46
   
6. “Studies on the Estimation of Cardiac Output in Man, and of Abnormalities in Cardiac Function, from the
   Heart!s Recoil and the Blood!s Impact; the Ballistocardiogram” – Starr,I., Rawson,A.J., Schroeder, H.A.,
   and Joseph, N.R. – 1939
   
7. “Clinical Ballistocardiography” – Brown, H. , deLalla, V. , Epstein, M. ,Hoffman, M. – The MacMillan
   Company 1952
   
8. “Ballistocardiography: A Clinical Review” - Piney Pollock - Can Med Assoc J. 1957 May 1; 76(9): 778–783.