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Medical Tips for the Endurance Athlete: When Should I Seek a Sports Cardiologist

This is a guest post by Dr. Jonathan Kim MD, FCAA

Case Example. A 54 year-old triathlete (high-level recreational endurance athlete for the last 25 years, competing in 20 marathons and 4 Ironman™ triathlons) presents with exercise intolerance. At baseline, the patient runs 40 miles per week. For the last several months, the patient complains of excessive fatigue and shortness of breath during long runs and bike rides. The athlete states that, “I can’t keep up with friends I used to fly by during races”. They have seen 2 prior cardiologists, but this is the first sports cardiologist seen in consultation. Previous testing included a  “normal” echocardiogram (ultrasound of the heart) and standard exercise treadmill testing. The stress test was stopped because the patient achieved maximum heart rate; there were no symptoms. The patient was previously told nothing was wrong with them because “you compete in triathlons and run 50 miles per week”.

This hypothetical case is, in fact, a description of a common patient seen in general cardiology clinics across the country and an example of why sports cardiology is becoming an integral and essential component of preventive cardiology, specifically for the athletic patient or anyone who places a high premium on exercise performance. Without sports cardiology expertise and significant exposure to athletic patients, one may agree that the patient described is truly “fine”. How could someone this fit have significant exertional shortness of breath and fatigue? Wasn’t there a normal echo and stress test?

Athletes, including recreational endurance exercise participants, typically demonstrate increased cardiac reserve and functional exercise capacity compared to those patients who are more sedentary. As such, subtle perceived changes in exercise tolerance may be representative of underlying cardiovascular abnormalities including coronary artery disease, cardiac arrhythmias, hypertension, and many other pathologic conditions that may be much more obviously presented in a sedentary subject a part of the general population. Clearly, exercise-induced symptoms suggestive of cardiovascular disease such as chest discomfort, shortness of breath, dizziness/fainting, or palpitations clearly warrant further clinical investigation in any patient.

Since the 1990’s, the number of women and men who participate in recreational endurance exercise events in the US continues to rise at a record pace. These striking trends indicate that participation in these endurance exercise events will continue to rise over the coming years and that participants across the age spectrum will begin to engage in recreational endurance exercise. While not every participant requires a cardiac evaluation prior to endurance exercise training, it is paramount for those with concerns, history of cardiac risk factors such as smoking, high blood pressure, high cholesterol, family history of early coronary artery disease, and/or previous sedentary lifestyles to discuss these new exercise aspirations with their doctor. Further referrals to the sports cardiologist may be necessary, but advice regarding risk, healthy training habits, and healthy lifestyle habits can also be discussed with the primary care sports medicine or primary care medicine practitioner.

Going back to the case example: This case illustrates the important point that symptoms experienced by fit ultra-endurance athletes may be subtle, but should not be ignored. In addition, appropriate testing is critical to the evaluation and work-up of the endurance athlete. Although this triathlete had previous “normal” testing, “standard” exercise protocols are not adequate for an elite endurance athlete. Moreover, the functional capacity of this athlete was not assessed properly. The more appropriate test of choice would have been a cardiopulmonary exercise test, utilizing specific exercise protocols in attempts to replicate the training conditions experienced by the athlete. From an echocardiographic standpoint, there are newer, more sensitive echocardiographic techniques that may detect mild abnormalities not readily evident using standard echocardiographic techniques. Thus, the work-up remains incomplete despite “prior testing and reassurance”.

The sports cardiologist has an important role in the individualized medical care of all athletic patients, including endurance athletes. For the endurance athlete, concerning cardiovascular symptoms may be subtle, and it remains paramount for this growing population to be aware of when to seek appropriate medical counseling. Finally, with escalating numbers of patients engaging in recreational endurance exercise, appropriate risk stratification by history, prior to the initiation of strenuous exercise training in those who were previously sedentary, is recommended.


Dr. Jonathan Kim is a sports cardiologist and an Assistant Professor in the Division of Cardiology at Emory University who has developed a Sports Cardiology clinic at Emory-St. Joseph’s Hospital. Dr. Kim received his Bachelor of Science in Biology at Emory University in 1998. He was awarded a Fulbright Scholarship and studied in Melbourne, Australia before attending Vanderbilt University School of Medicine. He completed his internship and residency in Internal Medicine and Pediatrics at the Massachusetts General Hospital/Harvard University in Boston before completing his General Cardiology fellowship at Emory University in 2014. Dr. Kim was chief fellow at Emory between 2013-14. Dr. Kim additionally holds an adjunct professorship in the School of Applied Physiology at the Georgia Institute of Technology. He is the Team Cardiologist for several professional teams in Atlanta, including the Atlanta Falcons and Atlanta Hawks.

If you would like to schedule an appointment with Dr. Kim, call 404-778-6070.  Dr. Kim’s sports cardiology clinic is located at Emory Saint Joseph’s Hospital, 5671 Peachtree Dunwoody Road, Atlanta, GA 30342.


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