Charles Theodore Dotter: The Father of Intervention

Abstract

The 1st percutaneous transluminal angioplasty marked a new era in the treatment of peripheral atherosclerotic lesions. The early techniques used in peripheral percutaneous transluminal angioplasty form the basis for subsequent percutaneous intervention both in the peripheral and coronary arteries and are largely the contribution of Charles Dotter. Dotter was the 1st to describe flow-directed balloon catheterization, the double-lumen balloon catheter, the safety guidewire, percutaneous arterial stenting, and more. This practical genius dedicated his considerable energy to the belief that there is always a better way to treat disease. His personal contributions to clinical medicine, research, and teaching have saved millions of limbs and lives all over the world.

Necessity is the mother of invention is a silly proverb. Necessity is the mother of futile dodges is much closer to the truth. The basis of growth of modern invention is science, and science is almost wholly the outgrowth of pleasurable intellectual curiosity.

—Alfred North Whitehead (1861–1947)

Charles Theodore Dotter (Fig. 1) is generally credited with developing a new medical specialty, interventional radiology. His contributions to vascular and interventional radiology are fundamental and broad in scope. He was a leading force in Machlett's development of an x-ray tube capable of obtaining millisecond exposures. He was the 1st to describe flow-directed balloon catheterization, the double-lumen balloon catheter, the safety guidewire, and the “J” tipped guidewire. Percutaneous transluminal angioplasty was his landmark contribution. He also introduced the concepts of percutaneous arterial stenting and stent grafting by placing the 1st percutaneous “coilspring graft” in the femoral artery of a dog. He pioneered the techniques of low-dose fibrinolysis with injection of streptokinase directly into an occluding thrombus. Dotter (along with Marcia K. Bilbao) invented the “loop-snare catheter” for retrieving intravascular foreign bodies. He developed tissue adhesives for vascular occlusion and organ ablation. ¹

Fig. 1 Charles Dotter (ca. 1960)

(Courtesy of Oregon Health Sciences University)

The main theme of Dotter's work was the use of catheters for diagnosis and treatment in an attempt to replace the scalpel. He was 20 years ahead of his time, especially with percutaneous transluminal angioplasty. It would take that long for his peers in radiology and surgery to consider the idea seriously.^* Even today at his home institution, Oregon Health Sciences University, Dotter remains largely unknown.

In the words of Dr. Michael Baird, a colleague at Oregon Health Sciences University, “he was something of a radical when it came to doing things and being willing to try things. I think it made a lot of people nervous, but it also led to an enormous amount of progress.”^** Dotter had a flamboyant personality when he spoke in person or presented scientific papers. European physicians, who were more open to unproven techniques, almost immediately embraced percutaneous transluminal angioplasty, recognizing a “medical breakthrough.” His technique was even affectionately referred to as “Dottering an arterial stenosis.”^*

The Early Years

Dotter was born in Boston on 14 June 1920. He attended grammar school and high school in Freeport, Long Island. An excellent student, he skipped a grade in grammar school. Dotter had boundless energy as a child, but he was small for his age and had little interest in team sports. Instead, he turned to mountaineering as an athletic outlet. He was inquisitive as a child and was interested in mechanical things from an early age. ² He derived great satisfaction from working with tools and rarely encountered a machine he did not try to dismantle and attempt to find more uses for. In adulthood, Dotter designed his own “conceptual trademark” in the form of a crossed pipe and wrench (Fig. 2), both because he loved mechanical things and because this emblem meant “that if a plumber can do it to pipes, we can do it to blood vessels.” ³

Fig. 2 “My favorite conceptual trademark is a sketch that I did years ago of a crossed pipe and wrench. It's a gross oversimplification, of course, but what it means to me is that if a plumber can do it to pipes, we can do it to blood vessels.” ³

(Courtesy of the Dotter Interventional Institute)

Dotter received a bachelor of arts degree in 1941 from Duke University. He went to medical school at Cornell, where he met his future wife, Pamela Battie, a head nurse at New York Hospital. They were married in 1944. He completed his internship at the United States Naval Hospital in New York State, and his residency at New York Hospital. ² Dotter was only 30 years old when he was offered a position as a full-time faculty member at Cornell Medical School. By the time he took his 1st staff position, he had already written a number of articles in the area of his major interest—angiocardiography. Two years later, he took the position of professor and chairman of the Department of Radiology at the University of Oregon Medical School. At 32 years of age, he was the youngest person ever to be named chairman of a radiology department in a major American medical school. He would remain in that position for an additional 32 years. ² During those years, he developed an entirely new medical specialty, interventional radiology (Fig. 3). Along the way, he published more than 300 papers (of which he was 1st author on more than half), produced 3 scientific training films, and created nearly 20 scientific exhibits. ^1–4

Fig. 3 Dr. Dotter, hand-injecting contrast medium into his patients in the radiology suite.

(Courtesy of Oregon Health Sciences University)

The X-Ray Roll-Film

Angiocardiography was a new area of interest when Dotter entered his residency; it had been only 15 years since the right heart was 1st cannulated. The ideal way to visualize blood flow in the coronary arteries is with real-time fluoroscopy, but in the 1940s the developing field of angiocardiography was severely impeded by a technical limitation: radiographic images still had to be made one at a time. ⁵ The x-ray technician manually changed cassettes for each new image, in an effort to obtain as many images as possible while the contrast agent was still in the coronary arteries. Even the quickest technicians had gaps of a few seconds between exposures, which severely limited imaging studies of the heart. “In 1949, single-plate angiograms were replaced by automatic film cassette changers that produced a rapid series of ‘cut-films.’ Within a year the image intensifier was introduced; this device permitted the development in the 1950s of cineangiograms on roll film.” ⁶

It was Dotter who, in 1950, developed an automatic X-Ray Roll-Film magazine capable of producing images at the rate of 2 per second. ⁷ Although he was not a mechanical engineer, he clearly had an extraordinary ability to solve mechanical problems. The X-Ray Roll machine still stands the test of time and was the prototype for the modern grid-controlled x-ray tube. ¹

Bill Cook and the Teflon Catheter

One of the biggest challenges to catheter therapy was the catheter itself. As Dotter envisioned new uses for catheters, he needed new catheters. Throughout his career, he invented his own interventional tools, often using unconventional materials: guitar strings, VW speedometer cables, and vinyl insulation stripped from a piece of intercom cable found lying in a wastebasket. ³ Technicians in his lab manufactured all the catheters he needed, but as time went on, he needed a corporate partner. A man named Bill Cook, who would become the chief executive officer and sole proprietor of the world's largest supplier of angiographic supplies, was to play a pivotal role in Dotter's success.

Bill Cook met Dotter at a Radiological Society of North America meeting in Chicago in 1963. By that time, Dotter had a “state of the art” angiography laboratory in Oregon. There, his technicians made wire guides and produced Teflon catheters. Dotter himself made some of the catheters with a blowtorch. ⁴ Still, the demand was greater than they could cope with. “Cook Incorporated” was so new that Bill Cook was the sole employee. Cook recalls his 1st encounter with Dotter:

I was demonstrating to prospective customers how to pull tips on Teflon catheters when I noticed someone behind me sitting on a box. It was a short, muscular, bald man with darting eyes—I didn't know who he was, but he made me nervous. I turned and asked if I could be of help, and he said “no”—nothing more—and left. Just before we closed for the day he returned and asked if he could use my blowtorch and “borrow” some Teflon tubing. He said he wanted to practice making catheters in his hotel room. Thinking I had a real “space cadet” on my hands, I said, “Sure, may I have your name?” He answered, “Charles Dotter.” The next morning he was waiting for me with 10 beautifully made Teflon catheters and my blowtorch. Remember, I had just started my business, and I admit that those 10 catheters were sold to someone else for $10.00 each later that day. He was my first production employee. ⁴

On the last day of the conference, Dotter offered to fly Cook to Portland. It was during that 1st visit that Dotter gave him a sketch of 2 telescopic catheters. From those plans, the 1st dilation set, the “Dotter dilatation set,” was soon produced. ⁴ This is the same kit that enabled Dotter to perform the 1st percutaneous transluminal angioplasty. ⁴

Percutaneous Transluminal Angioplasty

Dotter's greatest contribution in radiology was the interventional catheter. Prior to “catheter therapy,” all vascular procedures were done as open surgeries. These involved general anesthesia, several days in the hospital, and all the complications associated with a surgical wound. Understandably, Dotter was very excited about a procedure that gave patients the same benefits they would receive from vascular surgery without as much risk. Throughout his career, his goal remained the same: to treat the patient without the scalpel, lowering morbidity and mortality.^* Although it would be many years before vascular surgeons would willingly refer their patients to radiologists for interventional procedures, vascular surgeons eventually accepted percutaneous transluminal angioplasty, calling it “endoluminal surgery.” ¹

The First Patient

Dotter's 1st arterial recanalization was quite inadvertent: in 1963, he accidentally “recanalized an occluded right iliac artery by passing a percutaneously introduced catheter retrogradely through the occlusion to perform an abdominal aortogram in a patient with renal artery stenosis.” ⁶ He reported this at the Czechoslovak Radiological Congress in June of that year ⁸ and immediately began to conceive of such improvements as balloon-mounted catheters and stents. ⁶

On 16 January 1964, Dotter and his trainee, Melvin Judkins, 1st used the catheter for intentional percutaneous transluminal angioplasty. The 1st patient to benefit was Laura Shaw, an 82-year-old woman who was admitted to the University of Oregon Hospital with a painful left foot. The foot had a nonhealing ulcer and gangrenous toes. All of her physicians had recommended amputation, but she had refused. Dr. William Krippaehne, a general surgeon, handled the vascular cases. He had a good relationship with Dotter, and because Ms Shaw refused surgery, Krippaehne asked Dotter to see her. Dotter found out that Ms Shaw had short segmental stenosis of the superficial femoral artery, an ideal lesion upon which to test his percutaneous “dilating” catheters. The procedure went well and within minutes, the patient's foot was warm and hyperemic. ² Her pain disappeared within a week and the ulcer soon healed (Fig. 4). Follow-up angiograms done 3 weeks and 6 months after Dotter's intervention showed the vessel to be patent (Fig. 5). Ms Shaw died of congestive heart failure almost 3 years later, “still walking on my own two feet.” ⁹

Fig. 4 Laura Shaw's left foot 1 week and 5 months after the procedure.

(From: Dotter CT, Judkins MP. Transluminal treatment of arteriosclerotic obstruction. Description of a new technic and a preliminary report of its application. Circulation 1964;30:654–70. Reproduced by permission of the American Heart Association.)

Fig. 5 Angiograms of Dotter's 1st catheter patient, Laura Shaw: A) before transluminal dilation of the left superficial femoral artery, B) immediately after dilation, and C) 3 weeks after the procedure.

(From: Dotter CT, Judkins MP. Transluminal treatment of arteriosclerotic obstruction. Description of a new technic and a preliminary report of its application. Circulation 1964;30:654–70. Reproduced by permission of the American Heart Association.)

Becoming Accepted

In the beginning, the relationship between vascular surgeons and interventionalists was adversarial. A surgeon from the community sent Dotter a patient for an angiogram of the left superficial femoral artery. The surgeon asked for a left femoral angiogram and boldly wrote on the form “visualize but do not try to fix” ⁴ (Fig. 6). The diagnostic angiogram (Fig. 7A) showed that both the superficial and deep femoral arteries had areas of stenosis. Dotter dilated the deep femoral artery. The post-treatment angiogram (Fig. 7B) shows the superficial femoral artery to be stenotic and the deep femoral to be widely patent. Dotter delighted in telling the story of how he got around the surgeon's orders. On a training video, he points out that it “only took a moment” to dilate the stenosis. ⁷ Since Dotter performed meticulous follow-up on his patients, he was often able to demonstrate how his techniques saved their lives. In this patient, the planned open superior femoral arterioplasty procedure eventually failed, while the interventional dilation of the deep femoral remained open. Dotter delighted in pointing out how his dilatation of the deep stenosis, which remained patent for 5 years, saved the man's leg. ⁹ There is a remarkable photograph of Dotter and this patient on the summit of Mt. Hood (ca. 11,000 ft), taken about a year after the procedure (Fig. 8).

Fig. 6 The consultation request that Dotter received in 1964.

(Courtesy of Oregon Health Sciences University)

Fig. 7 Angiograms of the “Do not fix” patient, showing atherosclerotic narrowing of the deep femoral artery A) before and B) after transluminal dilation.

(From: Dotter CT, Judkins MP. Transluminal treatment of arteriosclerotic obstruction. Description of a new technic and a preliminary report of its application. Circulation 1964;30:654–70. Reproduced by permission of the American Heart Association.)

Fig. 8 The “Do not fix” patient and Dotter (on right) after reaching the summit of Mt. Hood (ca. 1965). This image is taken from a VHS copy of the original 16-mm film.

(From: Dr. Dotter's training video for percutaneous transluminal angioplasty. Courtesy of the Dotter Interventional Institute.)

The attitudes toward percutaneous transluminal angioplasty in American surgical departments began to change in 1974 when a Zurich cardiologist, Andreas Grüntzig, developed a balloon catheter capable of dilating peripheral arteries. After Grüntzig described the first 5 cases of percutaneous transluminal coronary angioplasty in a letter to the editor of Lancet in February 1978, ¹⁰ physicians became more receptive to the idea of transluminal angioplasty. By 1981, Dotter was able to describe the relationship between the interventional radiologist and the vascular surgeon as “excellent.” ³

Grüntzig, who contributed so greatly to the changing attitude, had a different “style” from that of Dotter.^* Melvin Judkins, who trained at Oregon Health Sciences University under Dr. Dotter and also knew Dr. Grüntzig, told it this way:

Dr. Dotter frequently presents ideas in a nonconservative way. Now Dr. Grüntzig is just the opposite; he presents himself as supercautious, where Charlie presents himself as aggressive. And I think both individuals present themselves a little bit differently than they really are. I would describe Dr. Dotter as an individual who develops concepts, who is innovative, who likes to work on the frontiers of development …. Dr. Dotter has frequently been dubbed “Crazy Charlie” because of lack of understanding of his innovative and nonconventional ideas. ³

Whereas Dotter openly ignored the social norms of the medical establishment, Grüntzig was careful to follow them. He took care to present himself in a conservative and scientific light. Grüntzig quickly gained fame for his technique and his persona. “Gruentzig's fame and acceptance helped Dotter because, knowing about ‘Dottering’ and realizing that everything he accomplished was based on Dotter's approaches, he openly gave credit to Dotter—something few cardiovascular surgeons were willing to do until the late 1970s.” ⁵ With Grüntzig behind Dotter, others finally began to give him credit for something he had done nearly 15 years before—the 1st percutaneous transluminal angioplasty. ³

Dotter hoped that his work would eventually translate into improved patient care and stimulate new ideas. In an interview, Dotter explained:

Things have been both rewarding and at times frustrating. In the early days of transluminal angioplasty I had to accept a lot of unpleasant backbiting such as ‘He's a nut, you can't trust his uncontrolled, poorly documented case experience,’ and worse. I'm glad I was thick-skinned enough to stick with it and even more glad that there's so much still to be done and so many others to help do it. ³

Percutaneous transluminal angioplasty, an idea 1st presented and later developed by Dotter, has surpassed all expectations. At the time of its development, Dotter was frustrated because people thought he was rushing in where he should not go. ⁵ Although his ideas were slow to be adopted, this pace was not unexpected. Even in his darkest times, Dotter knew that some of the greatest breakthroughs in medical history had met with the same reaction, but had proved their worth in time.

Coronary Angiography—“A Pressing Responsibility”

Another Dotter “project” was to develop a new method to reliably and safely visualize the coronary vessels. In July of 1958, he published an article in Radiology on the technique called “occlusion aortography,” in which he described his canine experiments (Fig. 9). ¹¹ Prior to this time, there had been no reliable way to visualize the coronary vessels. His method employed a soft, double-lumen balloon catheter. One lumen opened at the tip of the catheter and a 2nd, smaller lumen had a side opening in the catheter wall about 1 inch short of the tip. The latter lumen provided access to a sleeve-like, latex balloon secured to the shaft of the catheter above and below the side orifice. When distended, the balloon was large enough to occlude the human aorta. Under a light general anesthetic, the catheter was advanced from the radial artery to the aorta, where the balloon was inflated with nitrous oxide or carbon dioxide. After trial inflations to determine the correct location and amount of gas for occlusion, the examination proper was carried out. The balloon was quickly inflated, a small amount of contrast medium (4 mL) was injected through the distal lumen, and a series of x-ray exposures was made for 6 to 8 seconds. The balloon was then deflated and the catheter withdrawn. ¹¹

Fig. 9 Selective coronary arteriogram in the normal dog by the technique of occlusion aortography.

LAO = left anterior oblique

(From: Dotter CT, Frische LH. Visualization of the coronary circulation by occlusion aortography: a practical method. Radiology 1958;71:503-23. Reproduced by permission of the Radiological Society of North America.)

Earlier angiocardiographic techniques had depended on the injection of a large amount of contrast agent into a peripheral vein. Dotter believed that technique to be “worse than useless” for studying coronary artery occlusion. ¹¹ His conclusion was based on a case series of 4,000 angiograms that had led to the diagnosis of only 1 intrinsic coronary artery lesion, a coronary arteriovenous fistula. ¹² Cardiac ventriculography, the injection of contrast through a needle inserted through the chest wall, pleural space, pericardium, right ventricular myocardium, and interventricular septum, caused arrhythmias; and the opacified vessels were partially obscured by the opacified left ventricle. ^13–15 The only other option, thoracic aortography, failed to produce recognizable opacification in 30% of the aortograms, and in better than half the cases only 1 coronary vessel was visualized. ¹¹ This was the frustrating state of coronary angiography at the time that Dotter introduced controlled vascular occlusion as a way of visualizing the coronary vessels.

Occlusion aortography produced beautiful images of the coronary vasculature. In Dotter's 1958 Radiology article, he reported that all 78 dogs survived the procedure. ¹¹ In addition, in this study, acetylcholine was used to cause transient cardiac arrest, which markedly improved the quality of the images. ¹⁶ Unfortunately, the risk of ventricular fibrillation was great and, in this era before closed-chest defibrillation and cardiopulmonary resuscitation, the technique never “caught on.” ⁵ Dotter tried to allay fears about occlusion aortography when he stated: “the main risks of occlusion aortography without the acetylcholine are (1) operative technic or the hazards of aortic catheterization per se; (2) effects of aortic occlusion, in relation to physiologic consequences; (3) choice of contrast agent or the toxicology of coronary visualization.” ¹¹ Dotter asserted that all 3 factors added up to a small risk for the patient. The “risk of occlusion aortography can be reduced to a minimum defined by technical competence …. Complete circulatory arrest for a period of one or two minutes is without danger, particularly when coronary flow is maintained. To think otherwise would … cast aspersions on the honored sphygmomanometer cuff.” In addition, “the alternatives to thorotrast [a contrast agent] are drugs which offer a considerably greater risk to the patient than the hazards associated with incompletely diagnosed coronary artery disease.” ¹¹

At the time, surgeons, too, were having trouble with coronary artery disease. Because there was no good way to visualize the coronary vessels, they had no way to know where to operate. In his Radiology article, Dotter states, “The development of improved methods for radiographic demonstration of the coronary vessels in man is one of radiology's most pressing responsibilities. Once this is achieved, there should result a significant acceleration toward what is hoped will be a successful surgical attack upon coronary vessels.” ¹¹ Boldly, Dotter makes his expectation clear. One wonders whether he yet had plans to use angiographic imaging to treat patients with his “catheter therapy”—which is, of course, what he and his colleagues in radiology eventually did. The foundation prepared by these early imaging studies, together with the better-known work of Mason Sones, formed the basis of modern angiography. It was in October of that same year (1958) that Sones accidentally intubated the ostium of a patient's right coronary artery and selectively opacified that vessel before he could remove the catheter. Selective opacification eclipsed Dotter's occlusion aortography as a method of imaging the coronary vasculature. Indeed, Dotter sent Melvin Judkins to Cleveland to learn Sones's technique for use in Portland—at the request of Albert Starr, who wanted to evaluate prosthetic-valve candidates over the age of 50. ⁶ Having learned coronary angiography from both Dotter and Sones, Judkins subsequently developed an improved set of catheters that would seek out the coronary ostia, regardless of aortic structure. ⁶

Right Heart Catheterization

In 1950, Dotter turned his attention to the use of balloon-tipped catheters to study circulation. Dotter developed an ingenious balloon method that could produce a reversible increase in pulmonary resistance and completely obstruct a branch of the pulmonary artery. ¹⁷ A similar double-lumen, flow-guided catheter designed to measure right heart pressures was marketed by Swan and Ganz in 1970. ¹⁸ The Dotter catheter was made by mounting a rubber balloon near the tip of an 8.5-F catheter. His objective was to create a measure of right heart function that used the ability of the right ventricle to pump against a controlled resistance. In animal models, he recorded pressures in the femoral and right ventricular arteries before and after inflation of the balloon in the pulmonary artery. ¹⁷

While Dotter was developing his balloon catheter, he also created a flow-guided catheter for the right heart and pulmonary artery. ¹⁹ At the time, this was quite an innovation because it was not easy to find a suitable material: radiopaque, sterile, and with an anticoagulant surface. Dotter experimented with many combinations of materials, including “specially dipped latex tubing and military surplus electronic insulation” before settling on Silastic, an inorganic silicone rubber.

The 1st flow-guided cardiac catheterization kit to be marketed was the one developed by Swan and Ganz. This same kit in a slightly modified form, the Swan-Ganz catheter, is now used routinely throughout the world. Although Dotter invented both a balloon catheter, and a balloon catheter capable of measuring right heart pressures, he was never able to put the 2 together. ⁵ Without the attached balloon, the catheter was prone to “tangle” in the vasculature, with the potential for serious complications.^*

When he was developing his flow-guided catheter, therapeutic applications of the device were on Dotter's mind. Prior to the use of flexible tubing, passing a catheter into the pulmonary artery could require 10 to 30 minutes. The patient was made as comfortable as possible, placed in the left lateral recumbent position, and left there for half an hour, so the catheter would have time to work its way into the heart. Dotter believed that this was much too long. In a seminal article on Silastic “flow guided” cardiac catheterization, ¹⁹ he alludes to the brief “free phase” of pulmonary embolization. “During the time required to read this sentence, the reader's antecubital veins will be traversed by 3 or 4 billion red cells, virtually all of which will, within 2 to 4 seconds, reach the pulmonary artery. The free phase of pulmonary embolism is similarly brief. Why, then, does it require an average of 10 to 30 minutes to pass a cardiac cath-eter into the pulmonary arteries?” ¹⁹ The Silastic cath-eter solved this problem.

This advance inevitably led to the idea that pulmonary emboli could be treated by catheterization. In the same article, ¹⁹ Dotter shows the injection of contrast medium through a catheter into a mid-sized pulmonary artery. Similarly, Dotter pioneered the injection of streptokinase into the pulmonary vasculature as a treatment for pulmonary embolism. ^20,21 Although the use of streptokinase was eventually abandoned in the United States due to a high incidence of lobar hemorrhage, it is still used in other countries as an important treatment for acute pulmonary embolism. ^22,23

One wonders why the Silastic catheter, like nearly all of Dotter's ideas, was not immediately embraced as an important innovation in both diagnosis and treatment. In an unpublished interview, Josef Rösch comments that at the time “he [Dotter] was interested in cardiac treatment, not diagnosis …. It seemed to him to be too traumatic. He was always thinking of how to do it easier, more effectively.”^* In a 1965 lecture, Dotter comments, “Since flow-guided right heart catheterization is neither difficult nor time-consuming, and, since vascular cut-down is not required, it is possible to study pulmonary blood pressures in hospital populations.” He specifically mentions the development of an “economic, sterile, ready-for-use catheter pack,” as well as a battery-operated, lightweight amplifier and transducer for use in the field. ²⁰ But the combination of potential complications, Dotter's lack of controlled trials, and professional skepticism prevented the Silastic catheter from going very far.

Dotter the Person

Dotter was a risk taker. “He was a pilot and a flyer [in cars] and a mountain climber, and one of those people that just did things.”^* He was a Renaissance man. Rösch remembers, “Charles always found time for his wife Pamela, three children, and close friends, as well as classical music, painting, photography and outdoor living.” ⁴ “Charlie was such a dramatic person. He was climbing mountains, painting pictures, doing things in x-ray, always on the move.”^* Dan Labby, who was chief resident in internal medicine at Cornell when Dotter rotated through as a student, remembers Dotter well. “He was very flamboyant. On top of that, he was extremely intelligent, had a very broad intelligence. Everything interested him. He was a mountain climber, he drew and painted beautifully, and so on. He was an amazing man.”^** Herbert Adams, a colleague and friend at Stanford, remembers Dotter for his “fertile mind, caustic comments, strong convictions and his understanding and belief that there were other ways to help sick people and that he had some of the answers.” ⁴ Of his style in medicine, a colleague said, “Charles Dotter had thirty brilliant ideas a day. It took the rest of us to figure out which one was really worthwhile.”***

Dotter was an accomplished mountaineer. He made it a goal to climb all 67 peaks over 14,000 feet in the continental United States, and it was a goal he accomplished. This was despite 2 bouts with Hodgkin's lymphoma and 2 open-heart surgeries for coronary artery stenosis. He tried never to let his medical problems slow him down. For example, he celebrated the favorable outcome of mantle radiation therapy for his 1st occurrence of Hodgkin's in 1970 by climbing the Matterhorn without a guide. ⁴ Stories of Dotter's adventures on mountains quickly spread throughout the staff of the new University Hospital. Nelson Niles remembers how it would go: “He'd decide he was going to do it [climb a mountain], and he'd pile his wife, maybe, and a friend or two who [were] going to go with him, and a couple of dogs, he always liked to take dogs, and they'd drive for a thousand miles, and he'd drive nonstop and then climb the mountain and then drive back.” Many people vividly remember experiences they had in the wild with Dr. Dotter.

Bill Cook recalls more than 1 such occasion:

During the 1960s and 1970s he would occasionally call and say, “Let's go out West.” One time in Montana, Charles … [was] having [coffee] at a restaurant in Beaverhead National Forest. All of a sudden, Charles ran out the door with his camera. Some time later, we found him at the foot of a tree talking to a young bear and snapping pictures. We later learned that the treed bear was one of the rogues that had killed several young people in Yellowstone Park and had recently been relocated in Beaverhead.

Charles also took me mountain climbing—once. There we were on Three Fingered Jack in a blizzard—never again! He also tried to talk me into flying under a bridge so he could take pictures for one of his films—I wouldn't do it. Next, he asked if I would fly him near several mountain peaks in Southern Oregon—I did, but he couldn't take pictures because of the turbulence and snow. ⁴

Another mountaineering story involves Lou Frische (a colleague) and Mount St. Helen's:

They had disappeared into the wilderness, and they didn't come back on time. The word was out that two doctors were lost on the mountain. Well, they didn't get lost …. There were reasons why they were slow and got kind of stuck, but they managed fine. When they got back to the university, there were signs everywhere in Radiology, “To Dr. Dotter and Dr. Frische: This way to the bathroom; this way to the cafeteria; this way to your office.” Everywhere there were signs. I think they never quite lived that one down.^*

Legends were also born on campus. One occurs in the setting of medical grand rounds at the University of Oregon Medical School around 1961. It is the one story most vividly remembered by people who worked with Dotter, because it is so characteristic of the things he loved to do.

Charlie was doing grand rounds that morning at eight o'clock for the Department of Medicine, and he was talking about what you could realize if you could get a catheter in the heart and what the graphs would look like. Well, he brought in a rather large—standing about six feet tall—cathode oscillograph, which is, you know, like a TV screen with these graphs on it. And he said, “I've been standing here and talking to you for about twenty minutes, and all this time I have had a catheter in my heart,” whereupon he rolled up his sleeve, and there was the end of the catheter. And he said, “Now I'll show you what a normal heart reading looks like.” So he went and he plugged himself into the machine, and we were all kind of gasping, you know. There's a man standing there with a catheter in his heart—and he moved it among the chambers of the heart as he stood there, and he explained what the graphs represented.^*

It was an absolutely horrifying example, but it was the kind of thing he did, to say it is perfectly safe, it can be done, it isn't dangerous.^**

He did these kinds of things precisely because he felt he had to. It was his way of building rapport with the medical staff, but conventional medicine being what it was, physicians were understandably taken aback by such demonstrations.

In a letter from Herbert Adams in the Department of Radiology at Stanford, some of Dotter's true personality outside of medicine is revealed.

One day in the 1950s, Charlie and his wife dropped by our home … with a small gift for our two children, aged 7 and 10. We lived on a hillside, among the redwood trees, with a large patio …. There, before the wide eyes of my kids, Charlie took the exhaust from a vacuum cleaner and proceeded to blow up a war surplus balloon until it was larger than the patio itself. As it reached the edge of the patio, a lovely rose bush with a nasty thorn punctured the balloon …. Charlie picked up my son, lifted him into the air and said: “Well, you win some and you lose some. That's life, sonny boy.”

And that was Charlie's way. If someone ridiculed his latest thought or shrugged his shoulders in expressive skepticism, Charlie was never daunted. Not only did you “win some and lose some,” but also “time would tell.” ⁴

This was Dotter, kind with children and surrounded by loving, supportive friends, but aggressive with other colleagues and often ridiculed by them. His personality and drive were very strong and tended to provoke equally strong, polar reactions. It was in this setting that Dotter made most of his consequential discoveries.

Contributions in Forensic Pathology and Life-Support Therapy

In 1961, while a consultant to the state crime laboratory, Dotter published “Murder by Suffocation,” a case report in dental radiography and photography. ²⁴ The subject appeared to have been beaten to death in a drunken altercation, but was the beating the only cause of death? Radiographs of the skull revealed a lower denture in normal position, but a complete upper denture was seen lying transversely in the posterior oral pharynx. In view of this finding, the tongue, pharynx, and denture were removed en bloc. A fragment of soft-drink bottle was found lodged in the denture. A final autopsy report of “death by suffocation” was made. ²⁴

The following year (1962), Dotter published an article on cardiac resuscitation and “last chance” therapy in Electrical Engineering. ²⁵ In it, he presents ideas far ahead of their time. This article must have been submitted to a medical journal and rejected, then resubmitted to an electrical engineering journal. If so, rejection by medical reviewers is not surprising. The 1st line reads, “The stethoscope and electrocardiograph, time-honored tools of medicine, are instrumental equivalents of the ear trumpet and smoked drum recorder.” ²⁵ Dramatic and trying to make a point, Dotter ignores etiquette.

The content is shocking as well. He forcefully supports the 2-year-old technique of resuscitation by closed-chest compression, now known as CPR, and the slightly older defibrillation technique. Dotter goes so far as to disagree with the American Heart Association over who should learn CPR. He states, “I believe the technique should be used without delay whenever sudden collapse and unconsciousness are accompanied by the loss of pulse or audible heartbeat. In such circumstances there generally will be much to gain and nothing to lose.” These techniques were quite revolutionary and were offered as alternatives to the then-standard open-chest massage that was used as a last resort in cardiac failure.

Probably a case he was involved with the year prior (1961) was behind this thought. The case is outlined in an article published that same year: ²⁶

Case I: A 38-year-old male was examined by contrast cardiovascular visualization prior to planned surgery for aortic valvular stenosis. Two or three minutes following an injection of Hypaque into the proximal aorta, chest pain and the characteristic electrocardiographic changes of myocardial infarction heralded the onset of left heart failure and acute pulmonary edema. Ventricular tachycardia soon led to ventricular fibrillation.

Dotter describes how the patient was kept alive for 3 hours with closed chest compression and mechanical ventilation. During that time, the patient was able to say good-bye to his wife and undergo aortic valvulotomy. Unfortunately, the infarction was large and the left ventricle was not able to regain function. ^25,26

With this case as a reference point, Dotter pondered the definition of death and argued that new interventional techniques have a role in the treatment of end-stage heart disease.

Unfortunately, it is difficult for physicians to alter the concept that death occurs when heartbeat and respiration cease. Not so, for death is an irreversible state. Thus, its clinical criteria cannot be rigidly stated if they are to be both useful and contemporary. Today it is possible to institute artificial circulation and respiration within a matter of seconds after the heart ceases to beat …. When means for its fabrication can be obtained, a special balloon catheter intermittently inflated within the heart shows great promise of providing a sophisticated means for emergency artificial circulation. Although resuscitative artificial circulation and respiration cannot be used indefinitely, they permit a new concept in medical treatment …. In this situation [the maintenance of the 38 year old for surgery] the most radical experimental technique can be regarded as risk-free and certainly offers the patient an infinitely greater chance than the customary alternative …. I believe this concept of planned “last chance” treatment warrants the serious and immediate consideration of my colleagues in medicine. ²⁵

The techniques to which Dr. Dotter referred would be taken seriously. His “special balloon catheter intermittently inflated within the heart” would evolve into the intra-aortic balloon pump, used today in cardiac surgery and cardiogenic shock; ^26,27 and “planned last chance therapy,” in the form of cardiopulmonary bypass, would become standard protocol for cardiac surgery.

Another idea that came out of the experience was the closed-chest compression machine, “the circulator.” ²⁶ Dotter understood the great amount of work required to perform closed-chest compression over prolonged periods of time and reasoned that “an anesthesia machine using room air is superior to chest compression for the purpose of artificial respiration. By analogy, even greater advantage should result from the development of a mechanical device for compressing the heart through forced sternal depression.” ²⁶ A machine to do just that was manufactured by Dotter out of an electric motor, cam, and thrust rod with a rubber shoe that would attach to the patient's sternum (Fig. 10). The impetus behind the machine was the idea that, “In providing a temporary substitute for the heart which has failed, artificial circulation affords an opportunity to treat the basic disease after it has ‘killed’ the patient.” ²⁶ The circulator never established itself in patient care, but Dotter's point remains valid. It is true that “the moment when irreversible cell death occurs in human myocardial infarction is not clear.” Patients who have been maintained on left ventricular assist devices while awaiting transplantation are living proof that Dotter's basic vision was correct. Patients are kept alive in preparation for treatment of diseases that otherwise would have killed them long before.

Fig. 10 Simulated use of the circulator: electric motor, cam, and thrust rod with rubber shoe that contacts the patient's sternum. Patient lies between the motor board and the base of the external circulator.

(From: Dotter CT, Straube KR, Strain DC. Circulatory arrest: manual and mechanical means for emergency management. Radiology 1961;77:426-33. Reproduced by permission of the Radiological Society of North America.)

The Future of Catheter Intervention

As Dotter hoped, his catheter therapy is more and more often replacing the scalpel. Internal medicine, cardiology, cardiothoracic surgery, radiology, gastro-enterology, nephrology, neurology, neurosurgery, and gynecologic surgery all rely on interventional techniques to treat patients. The tenets presented in Dotter's 1964 article ²⁸ that describes the 1st interventional case still hold true today. Indeed his summation is understatement: “It seems reasonable to expect that the transluminal technic for recanalization will extend the scope of treatment beyond the limits of present day surgery.”

Acknowledgments

The author would like to thank a number of people for their support during this project. Rebecca Harrison, MD, Department of Medicine at the Oregon Health Sciences University, served as preceptor. Lynn Loriaux, MD, PhD, Chair, Department of Medicine at the Oregon Health Sciences University, served as editor. Dr. Josef Rösch, Professor and Director of Research at the Dotter Interventional Institute, provided several original articles, stories, and mementos, and served as an invaluable support during the project. Dr. Fred Keller, Director of the Dotter Interventional Institute, made editorial suggestions and provided historical references. Linda Weimer, MLS, MPS, of the Oregon Health Sciences University Oral History Project, provided the oral histories cited and the photographic portrait of Dr. Dotter. In addition, many physicians from Oregon deserve thanks for sharing their thoughts and memories regarding Charles Dotter.