August 17th, 2011

How Cardiologists Think

Today on CardioExchange, we launch a new mini-series of blog posts on decision making in cardiology. Dr. John E. Brush explores the conscious and unconscious mental strategies that cardiologists use in their everyday work and asks you to examine your own decision-making processes. The aim: to foster a rich dialogue about how we do what we do so that we ultimately improve the care of patients.

A 60-year-old man with systolic heart failure is admitted to the hospital for shortness of breath. You are making rounds when the nurse calls out that the man has collapsed in his room. You look at the telemetry monitor at the nursing station and immediately recognize that the patient is in ventricular tachycardia. After you shock the patient, normal sinus rhythm is restored and the patient recovers.

Another patient comes to the emergency room with chest pain. An urgently performed electrocardiogram shows ST-segment elevation in 3 leads. Without further questioning, the cardiac catheterization laboratory team and the interventional cardiologist are called in for an emergency procedure.

A third patient is admitted with unexplained fever and night sweats. She has new diastolic murmur on exam but also has some enlarged lymph nodes and a 1-week history of diarrhea. After a thorough evaluation and a careful weighing of the evidence, the patient is ultimately diagnosed with subacute bacterial endocarditis.

As these examples demonstrate, cardiology is a field that employs a variety of decision-making strategies. Some tasks demand instantaneous decisions; others require a more deliberative, logical approach. And many of our daily medical decisions are “best guesses” because of the uncertainty surrounding complex diagnostic dilemmas or therapeutic decisions that aren’t directly guided by a basic scientific principle or data from a clinical trial. For the rapid decisions, we frequently use mental shortcuts called heuristics. For the complicated but routine daily decisions, we often use intuition, inductive reasoning, and inference.

How doctors think is fascinating, yet the field of medical reasoning seems to be either ignored or assumed in medical education and practice. In my opinion, because there is enormous variation in how we all make medical decisions, many of those decisions may be suboptimal. Placing greater emphasis on medical decision making in medical education and research represents a big opportunity to improve the quality of medical care.

To examine medical decision making, one must start by evaluating the role of intuition. Whether using intuition is good or bad and whether we should allow our rational mind or our intuition to dominate our thinking has been a source of debate since the days of Plato and Aristotle. The debate raged through the era of the Enlightenment between Descartes and Hume, and through every age and generation since. In recent decades, the fields of cognitive psychology, behavioral economics, and evolutionary psychology have revealed insights into the structure of decision making and have renewed interest in the role of intuition and the value of heuristics. Many popular books such as Blink by Malcolm Gladwell and How We Decide by Jonah Lehrer have brought the research findings about intuition to a larger audience.

The wisdom of the ancient philosophers and the research findings of modern psychologists elucidate the complexities of human cognition in ways that could greatly improve the quality and consistency of medical decision making. As the educator and pragmatic philosopher John Dewey wrote in his book titled How We Think, “The aim of education should be to teach us rather how to think, than what to think — rather to improve our minds, so as to enable us to think for ourselves, than to load the memory with the thoughts of other men.”

Three recent books have raised awareness specifically about medical decision making. Jerome Groopman attracted much media attention with How Doctors Think, where he exposed the use of heuristics in medicine. The fact that we frequently use these cognitive shortcuts was news to much of the lay public, who may have assumed that medical decisions are exactly and precisely defined by rigorous science. In another book also titled How Doctors Think, Kathryn Montgomery posits that medicine is not a science, like Newtonian physics, but is rather a practice, where custom and routines enable doctors to think through the uncertain decisions that are part of their everyday work. She emphasized how doctors use narrative to construct a mental picture and employ abductive or retroductive reasoning to make clinical diagnoses. In Learning Clinical Reasoning, Jerome Kassirer and his coauthors offer numerous examples of the variety of thinking styles that doctors use, as well as the many fallacies and the biased reasoning that can often come into play in medical practice.

In designing a typical medical education curriculum, we tend to focus on the content of medicine: what is known and what is new. We often deny the fact that much is unknown and that many decisions are made under conditions of uncertainty. No common curriculum prepares physicians for the uncertainty of practice, and few courses explicitly teach the mental processes that help us cope with uncertainty. Greater focus on medical reasoning strategies in both primary and continuing medical education would help create a common vocabulary and structure that could improve those strategies and enhance consistency. In addition, greater emphasis on medical reasoning in real-world clinical practice could yield new opportunities for research that uncovers the components of good decisions and allows us to disseminate the best practices.

I started this commentary with three examples of decision making from cardiology practice. The first makes use of the recognition heuristic. The second uses a “take the best answer” heuristic. And the final example synthesizes a variety of cognitive processes, with the ultimate decision likely resulting from the use of either the anchoring and adjusting or the tallying heuristic. In the next several blog posts, I will expound further on these and other medical decision-making strategies.

As this series on decision making in cardiology progresses, I ask you, as CardioExchange members, to engage in dialogue — both with me and with one another — about this important topic. My hope is that together we will become more aware of our decision-making processes and ultimately use that understanding to improve practice. Please join the conversation.

5 Responses to “How Cardiologists Think”

  1. Savas Celebi, md says:

    we must sharpen our decision making by new data and repetition. we must use algorithms and guidelines.
    bytime, it will be just like driving a car. do you think cortically how to throw into gear or use gas pedals?
    it will become subcortical-maybe extrapiramidal?

    Competing interests pertaining specifically to this post, comment, or both:

  2. JOHN HAROLD, MD says:

    The commentary on How Cardiologists Think by Dr. John E. Brush made me look back to my mentors who introduced me to the clinical practice of cardiology. Dr. Brush examines the strategies that cardiologists use in their daily work and in clinical decision-making. Most of us evolved these traits during our clinical training. I had the privilege of working with several legends of cardiovascular medicine including Dr. Richard Gorlin, Dr. Simon Dack, Dr. Jeremy Swan, Dr. James Forrester and Dr. P.K. Shah. Each of these master teachers influenced my professional development and approach to patient care and clinical decision making. They introduced me to the clinical reasoning process, learning to generate and refine diagnostic hypotheses, to use and interpret diagnostic tests and to assemble a working diagnosis all too ultimately improve the care of patients. Many of these traits evolve through empiric training and without the platform that comprises the science of medical reasoning. We see only what we know and many of our daily decisions are best guesses.

    As Dr. Brush highlights, for the complicated but routine daily decisions, we often use intuition, inductive reasoning, and inference. Decision-making strategies and science has evolved since the days of my training. We need to be cognizant of how cardiologists think and involve the science of medical reasoning in the development of competency based training. This linkage is critically important as our profession is a field that employs a variety of decision-making strategies. The American College of Cardiology Foundation (ACCF) is embarking upon an initiative to identify the specific clinical competencies or “milestones” that should be attained by cardiology trainees during their fellowship training. This initiative also hopes to the align the curriculum competencies that patients and accrediting bodies can reasonably expect the general cardiologist who has been in practice for ten years or more to maintain. The ACCF will work with the Accreditation Council for Graduate Medical Education (ACGME) and the American Board of Internal Medicine (ABIM) in defining the continuum of competency requirements for our specialty, along with the associated evaluation and education tools. The science of medical reasoning will be an important addition to this competency curriculum. We should strive to prepare trainees for the uncertainty of clinical practice and teach the mental processes that facilitate dealing with uncertainty and to emphasize the components of good decision making that allows the dissemination of best practices. I concur with the observation that “the aim of education should be to teach us rather how to think, than what to think — rather to improve our minds, so as to enable us to think for ourselves, than to load the memory with the thoughts of other men.”

    We also need to be cognizant of the roles of professionalism and medical ethics in clinical decision making and support those attitudes and behaviors that serve to maintain patient interest above physician self-interest. Dr. J. Willis Hurst recently wrote “Dr. Francis W. Peabody, We Need You” (Tex Heart Inst J. 2011; 38(4): 327–329). Although retired, Dr. Hurst continues to teach medical students, house officers, and practicing physicians. After hearing about the unprofessional behavior of a few cardiologists, Dr. Hurst told his trainees that the profession needed Dr. Francis W. Peabody. These “contemporary” students had not heard of Dr. Peabody or his 1927 seminal publication in JAMA: (Peabody FW. Landmark article March 19, 1927: The care of the patient. By Francis W. Peabody. JAMA 1984; 252(6):813–8). Dr. Hurst read to them the last part of the speech that Peabody gave to the medical students at Harvard in 1926:

    Time, sympathy and understanding must be lavishly dispensed, but the reward is to be found in that personal bond which forms the greatest satisfaction of the practice of medicine. One of the essential qualities of the clinician is interest in humanity, for the secret of the care of the patient is in caring for the patient.

    Dr. Hurst stated that “Is it important for patients to know that their doctor cares about them…Doctors must not simply memorize their actions and comments like actors do when they act in a play…”

    Our mentors inspire us to professionalism and continuous professional development. We should become more aware of our decision-making processes and use that understanding to improve clinical practice. We must learn from the science of medical decision making and I look forward to further dialog in CardioExchange on this important topic.

    John Gordon Harold, MD, MACC, MACP, FCCP, FAHA
    Vice President, American College of Cardiology
    Member, Executive Committee, American Board of Internal Medicine
    Clinical Professor of Medicine, David Geffen School of Medicine at UCLA

  3. John E Brush, MD says:

    Thank you, John Harold, for your insightful comments and for your ongoing contributions to the profession. As the ACCF, ACGME, ABIM, and other organizations incorporate medical reasoning into their core clinical competency training, it will be necessary to determine what to include, how to present the topics, and what to test. I hope this series can create a dialogue that will help you and other leaders as you move in this direction.

    I also appreciate your comments about professionalism. One aspect of professionalism is shared decision-making. I think that our patients expect us to use our expertise and experience to guide them through the process of making complex medical decisions. To do this, we, ourselves, need to have a good understanding of medical decision making. We should be able to clearly explain our probability estimates and logic.

  4. “Data is not Knowledge,
    Information is not Wisdom.”

    Sequential assimilation of acquired historical elements(the history), physical diagnosis, pathophysiology and mechanisms of disease followed by test ordering and interpretation, and, ultimately, culminating in treatment or no treatment has important cognitive nuances and pitfalls unique to each step of the sequence. To add to Drs. Brush’s and Harold’s reference base, I call attention to an article by Newman-Toker and Pronovost on diagnostic errors (Diagnostic Errors—The Next Frontier for Patient Safety, JAMA 2009;301(10):1060-1062) and also in The Sunday Magazine of the New York Times(8/21/2001) entitled “To Choose Is To Loose” by John Tierney. The latter defines and explores the concept of “decision fatigue”, a phenomenon with which all clinicians should be aware and learn to manage.

    • John E Brush, MD says:

      Thanks for the references. I like the title and the article and I think that Clinical Reasoning should be the next frontier for quality of care. There are many references scattered out there, but no common curriculum, no common themes, and a lot of variability in practice.