The history of medicine has been marked by a perpetual contest, waged by those who propose innovative clinical techniques or technologies and those who resist its widespread use or adoption. As technologic advances in diagnostic imaging continue to leap forward, the cardiologist in the 21st century confronts this back and forth on a regular basis, with both sides offering salient arguments in their favor. History can offer insights into the potential risks and benefits of the implementation of technology and perhaps can provide a navigational guide to the current array of diagnostic testing available to the modern cardiologist.
Until the 19th century, physicians, while having a more precise understanding of the nature of disease in the deceased human body, still had considerable difficulty understanding and diagnosing diseases in the living. The gradual development and enthusiastic reception of technologic aids, then as now, represented remarkable advancements in the evolution of medical practice over the course of the last 200 years. Prior to the development of medical instrumentation, physicians were purely reliant on the patient's subjective symptoms and a few signs that were readily observable. In 1761, Joseph Leopold Auenbrugger of Vienna published a groundbreaking work entitled Inventum Novum, in which he described a new diagnostic method he coined chest percussion. In his work, he documents how by using his technique, one could distinguish between sounds of a healthy chest and a chest affected by pneumonia or tuberculosis.1
Although Auenbrugger's work enabled physicians to make more precise diagnoses, it was largely ignored for several years.2 Despite its limited implementation, it did indirectly influence a French physician named René Théophile-Hyacinthe Laennec. In 1816, drawing from his mentor's enthusiastic acceptance of Auenbrugger's technique, Laennec invented the stethoscope.3 In On Mediate Auscultation, Laennec describes the circumstances that led to his inspiration to use a cylindrical cone to listen to all manner of sounds in the chest. Like any new technologic innovation, the stethoscope had its detractors. Many physicians felt that using the stethoscope was undignified and ludicrous. However, Laennec, undeterred, meticulously correlated the sounds he heard through the stethoscope with postmortem pathologic findings. For many years after his initial description, even after its merits were becoming widely accepted, there was still considerable controversy regarding the technical and acoustic merits of monaural versus biaural instruments.2 Roughly 150 years later in the 1950s, Carl Hellmuth Hertz, a physicist, and Inge Elder, a cardiologist, were also using sound waves in an equally revolutionary way. By reflecting sound waves off of the heart, they were taking the first steps toward modern echocardiography.
It seems laughable today to question the merits of echocardiography or even the stethoscope, but in their day, each of these advances had their detractors and naysayers. The continual questioning and examination of the merits of technologic advances, however, is a vital part of their development. Although this Darwinian approach has seen many evolutionary leaps in diagnostic testing ...