“If It Isn’t Fun.” – M.S. in Medicine
As research fellow in the Laboratory of Physiological Hygiene in 1956, I took up a tradition at Minnesota for medical and surgical fellows to seek graduate degrees in research. The formal degree was unimportant in itself and contributed little to academic reputation or earning power, but the experience and discipline involved were thought to be worthwhile. At any rate, in those days, it was the thing to do. The research questions were usually posed and assigned by the fellow’s mentor and were often pedestrian or methodological, but the technique, understanding, and integrity engendered with the hands-on experience of data collection and measurement and analysis, the writing and presentation, were a cold bath for the dilettante or a sound preparation for the embryonic serious investigator.
I introduced my M.S. thesis as follows: “The duration of the QRS curve of the electrocardiogram (ECG) is a measure of time during which ventricular myocardium becomes electrically excited for contraction. Since correct measurement of QRS duration depends upon accurate determination of earliest and latest activation potentials, the QRS interval measured classically in frontal plane limb leads rarely represents total duration of the spread of excitation.”
In those days, the early 1950s, my mentor, Ernst Simonson, was collaborating with biophysicist Otto Schmitt at Minnesota in development of the most advanced quantitative stereo-vector-electrocardiographic system, SVEC III. On a six-month research assignment, I landed in the midst of this fascinating development, which was based on studies made in saline-filled models of graduate student torsos. In these, a current source (dipole) was immersed and countless surface measurements made to find those optimally orthogonal leads, X, Y, and Z also having least sensitivity to displacements in the dipole position.
Moreover, with his engineers, Schmitt had constructed an ingenious teaching device having a plastic toy at the center and resolvers so that the observer could place himself in any position in space in respect to the toy and, while peering through a stereoptikon, witness a live display of the P, QRS, and T vector loops of the ECG flashing through space. In frontal view, the QRS loop would usually zoom toward the observer, then sweep down and away and around to return again to the origin. In a horizontal view, rotating oneself directly above the doll, it became clear (in the photograph) why the vectors of earliest onset and latest offset of activation, being perpendicular to the frontal plane, would not register at all on the frontal leads of the conventional electrocardiogram. And by tradition, since Einthoven’s day, those were the leads in which wave durations were measured.
Thus, the intent of my thesis was to measure spatially correct ECG intervals. This was hardly an earthshaking topic, but for me it was a happy immersion into the tedium, satisfactions, and mysteries of empirical research.
Elsewhere I describe how I recruited the population of Navy personnel and made the SVEC recordings at rest and after effort. Then I mounted the jet-written records and projected them to 10 times magnification onto a screen in the somber old library of the LPH underneath Memorial Stadium, making direct measurements of QRS onset and offset with a plastic ruler, to 1 or 2 milliseconds accuracy. The mean QRS value was 0.1010 secs. (s.d. 0.0104) and 54 percent of values fell above 0.10 seconds, which was then the upper normal limit in conventional electrocardiography. The QRS appeared to lengthen a fraction with exercise.
The precision and tediousness of this thesis work took me back to days in quantitative chemistry lab. at the University of Miami. I came to think that I could be happy as a laboratory type in a lifetime of passionate isolation and mystery, free and intense, working in silence under bright lights in darkened rooms. At any rate, I worked late into the evening in the library and would often arrive home in Bush Lake to find my children long in bed and my wife long since exhausted. This went on for a number of weeks.
The board of examiners for my oral defense of the thesis was headed by my VA attending, Ralph Smith. The only query I recall was his: “How many metabolic equivalents (later called Mets) are reached in Grave’s disease (thyrotoxic goiter), and how does this compare with that achieved in exercise?” My guess, 10 to 15 mets in each, was a sufficient approximation. At any rate, he claimed to be impressed.
The thesis was carefully written up and properly bound and submitted to the graduate school and a companion article was soon published in the American Heart Journal. Since then, I have rarely seen it referenced by others. It may have died the quiet death of the SVEC III lead system of Schmitt and Simonson itself. But the hard work, the intensity of the solitary, late-night vigils, the self-discipline to complete the whole, and the satisfaction of publication — all were addicting. At the time I thought that I could well spend my life at such laboratory work — if only.
But the “ifs” were not to be: neither my rate of new ideas nor my biophysical expertise was sufficient to continue in that line. My natural leanings came more and more toward the larger health issues of prevention. But in the end, the M.S. thesis was a wonderful and seductive, if only a fringe experience in scientific method. With it, I also learned scientific etiquette, illustrated in these acknowledgments:
“Dr. Ernst Simonson has directed my attention to the cardinal problems in electrocardiographic theory, and to the necessity for improvement of quantitative differentiation between normal and abnormal electrocardiograms. His wide knowledge of the field, his battery of ideas, and his stimulation to research have been an impetus to my interest and studies.
Dr. O. H. Schmitt and Dr. R. B. Levine of the Biophysics Department have been much help in improving a lay concept of vector analysis and communications theory as applied to the electrocardiogram.
Professor Ancel Keys graciously supported my electrocardiographic studies during an assignment as Medical Fellow in his department.
Constructive suggestions by Dr. Ralph Smith of the VA Hospital are appreciated, as is the participation of Lt. G. K. Kennard and other naval personnel at the Wold-Chamberlain Naval Air Station.”