The Origin of Echocardiography?

To the Editor:

I read “The origin of echocardiography: a tribute to Inge Edler” in the Texas Heart Institute Journal.¹ As a medical consultant to the Journal and as one who lived and worked during the early years of cardiac ultrasound, I feel obliged to make some corrections and additions to that article.

First of all, I was not the first person to use the term “echocardiography” to describe the ultrasonic examination of the heart. To my knowledge, the word first appeared in print in an article by Dr. Bernie Segal of Philadelphia. I avoided the use of “echocardiography” initially, because there was no abbreviation for it. The obvious abbreviation for echocardiography would be ECG, and that had been preempted by the electrocardiogram. We could not use the abbreviation “echo,” because echoencephalography was still a viable entity. Only after echoencephalography ceased to exist as a diagnostic procedure were we able to adopt the term “echocardiography.” That made the “echo” abbreviation available for application to echocardiography.

My collaboration with Hal Dodge had nothing to do with ultrasonic instruments. We went to Alabama, where Hal was at the time, because he was doing biplane ventriculography, which was recognized as the gold standard for determining cardiac volumes. We needed an accepted gold standard for comparison with our echocardiographic measurements.

If “father” of a technique implies that a person was the first to use or introduce it, then I am not the father of echocardiography in the United States. When I accidentally stumbled onto diagnostic ultrasound by way of an erroneous advertisement in 1963, Claude Joyner and Jack Reid had already published a paper that duplicated Dr. Edler's mitral valve diastolic E to F slope technique for evaluating mitral stenosis.² I was not the first in the United States to use cardiac ultrasound.

When I saw my first ultrasound instrument, it clearly could not do what was advertised—measure cardiac volume. However, when I placed the transducer on my chest and saw a moving echo from the back wall of my heart, I immediately thought that I could use the gadget to detect pericardial effusion behind the posterior left ventricular wall. It turned out that I was right, and the technique proved to be the first reliable, long-lasting diagnostic application of cardiac ultrasound,³ with the possible exception of its use in detecting left atrial masses, which was first described by Sven Effert.⁴ Although Edler showed a patient with a large pericardial effusion anterior to the heart, anterior echo-free spaces are common and are nonspecific for fluid.

My first efforts were not inspired at all by Dr. Edler or Dr. Joyner. In fact, I visited Dr. Joyner and was most unimpressed with what he was doing. I noted very early that the mitral E to F slope promoted by Dr. Edler and later by Dr. Joyner as the principal use of cardiac ultrasound was unreliable and nonspecific. I then heard Dr. Edler lecture at a general ultrasound meeting in Pittsburgh in 1965. Again, I was thoroughly unimpressed: he mentioned only the E to F slope. It became apparent that he had done no further development of the technique since his movie had been shown at the European Congress of Cardiology in 1960 and a review article had appeared in the Acta Medica Scandinavica Supplement in 1961.⁵ I invited Dr. Edler to participate in the first meeting dedicated to cardiovascular ultrasound in January 1968 in Indianapolis. He did not lecture and only showed the 1960 movie.

The implication of the Texas Heart Institute Journal article is that today's practice of echocardiography is a direct result of Dr. Edler's work. That is not entirely correct. Inge worked in the field for less than 10 years. His efforts culminated in and apparently ended with the above-mentioned movie and review. Although Inge described several parts of the heart and some abnormalities that could be seen ultrasonically, the only application that he thought useful was the mitral E to F slope for the evaluation of mitral stenosis. The fact is that by the early and mid-1960s, the E to F slope already had been discredited; that disrepute cast doubt on all ultrasonic techniques, including those that were coming out of Indianapolis.

The notion that today's echocardiography is a direct result of Dr. Edler's efforts is, in today's terminology, a “disconnect.” In the early and mid-1960s, cardiac ultrasound was essentially dead. At that time, I could not find anyone in the United States or Europe working in the field, other than Dr. Joyner. Hellmuth Hertz had long since left the field, and, according to Dr. Effert (who also left the field), Hellmuth advised Siemens Corporation, the company that had provided the ultrasonoscope for Edler, not to enter the field because it had no future. I suspect that when Drs. Cournand and White rejected what he was doing, Inge also gave up on cardiac ultrasound. When I visited him in Lund in 1969, he was using the technique only for the mitral E to F slope. He had not adopted any of the applications demonstrated at the meeting in Indianapolis. I was also disappointed to learn that no one in Lund or any where else was carrying on in the field.

Thus, in our early years, we not only had to start from scratch, but we had to overcome some serious skepticism as a consequence both of failed techniques, such as ballistocardiography, and of discredited ultrasonic applications, such as the mitral E to F slope. It was very difficult to get our papers published and to have our techniques used clinically. As a result, we had to train a whole new generation of physicians not just in the United States, but all over the world—including Europe. We did this by developing new applications, training fellows, offering multiple meetings and preceptorships, giving many lectures all over the world, and publishing numerous articles and books. It truly would have been much easier for us if we really had been the first to use cardiac ultrasound.

My wife and I had the privilege to be with Inge and his wife Karin on many occasions. They were a delightful couple. Inge was a quiet, humble, and honest man. He would have been the first to admit that if we in Indianapolis had not resurrected echocardiography from the dead in the early and mid-1960s, his work would never have been recognized.

Harvey Feigenbaum, MD
Distinguished Professor of Medicine, Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis, Indiana