The Role of Nuclear Medicine in the Diagnostic Work-Up of Athletes: An Essential Guide for the Sports Cardiologist

Abstract

Athletes with heart disease are at increased risk of malignant ventricular arrhythmias and sudden cardiac death compared to their sedentary counterparts. When athletes have symptoms or abnormal findings at preparticipation screenings, a precise diagnosis by differentiating physiological features of the athlete's heart from pathological signs of cardiac disease is as important as it is challenging. While traditional imaging methods such as echocardiography, cardiac magnetic resonance, and computed tomography are commonly employed, nuclear medicine offers unique advantages, especially in scenarios requiring stress-based functional evaluation. This article reviews the use of nuclear medicine techniques in the diagnostic work-up of athletes with suspected cardiac diseases by highlighting their ability to investigate myocardial perfusion, metabolism, and innervation. The article discusses the application of single photon emission computed tomography (SPECT) and positron emission tomography (PET) using radiotracers such as [99mTc]MIBI, [99mTc]HDP, [18F]FDG, and [123I]MIBG. Several clinical scenarios are explored, including athletes with coronary atherosclerosis, congenital coronary anomalies, ventricular arrhythmias, and non-ischemic myocardial scars. Radiation concerns are addressed, highlighting that modern SPECT and PET equipment significantly reduces radiation doses, making these techniques safer for young athletes. We conclude that, despite being underutilized, nuclear medicine provides unique opportunities for accurate diagnosis and effective management of cardiac diseases in athletes.

Keywords: arrhythmogenic cardiomyopathy; congenital coronary anomalies; coronary artery disease; myocardial bridging; sports cardiology; sudden cardiac death; ventricular arrhythmias.

Figure 1

Representative example of a PET-TC merged image. (A) PET shows increased FDG uptake in the basal septum and basal lateral wall of the left ventricle (arrows). (B) chest CT image, (C) merged PET and TC image that allows better localization of the areas with increased uptake (arrows).

Figure 2

Representative example of an asymptomatic athlete with borderline ST-segment depression performed for preparticipation screening (A). Coronary computed tomography revealed moderate stenosis of the left anterior descending artery (B). However, stress-rest myocardial SPECT showed no inducible myocardial ischemia (C).

Figure 3

Representative example of an asymptomatic athlete with ST-segment depression performed for preparticipation screening (A). Coronary computed tomography revealed myocardial bridging of the left anterior descending artery (B). However, stress-rest myocardial SPECT showed no inducible myocardial ischemia (C).

Figure 4

Representative example of an athlete with premature ventricular beats at exercise testing performed for preparticipation screening (A). Further examinations revealed a right coronary artery originating from the left Valsalva sinus with slit-like ostium and narrowing of the interatrial course (B,C). Stress-rest myocardial SPECT revealed reversible ipoperfusion of the infero-lateral left-ventricular wall, tributary to the abnormal coronary artery (D).

Figure 5

PET-TC with FDG showing disomogeneous intense myocardial uptake, involving the interventricular septum and inferior wall.

Figure 6

Representative examples of myocardial uptake of Tc-99m]HMDP, typical of aTTR cardiac amyloidosis. From left to right—no uptake (Perugini 0), mild uptake (Perugini 1), moderate uptake (Perugini 2), and high uptake (Perugini 3).