Athletic Heart Syndrome

Introduction

Athletic Heart Syndrome (AHS) is a condition characterized by structural and functional changes in the heart due to prolonged, intense athletic training. These changes are generally benign but need to be distinguished from pathological cardiac conditions.

Causes

AHS occurs as an adaptive response to regular intense exercise, particularly endurance sports like marathon running, cycling, and swimming. The heart enlarges and becomes more efficient in pumping blood, leading to lower resting heart rates and increased stroke volume.

Key Features

• Bradycardia (low heart rate): Resting heart rates below 60 bpm are common in athletes.
• Cardiac hypertrophy: The heart muscle thickens, especially the left ventricle.
• Increased stroke volume: The heart pumps more blood with each beat, compensating for the slower heart rate.
• Normal ECG variations: Athletes often exhibit benign changes in electrical activity that should not be mistaken for disease.

Differentiation from Pathological Conditions

AHS must be distinguished from serious heart diseases, such as: - Hypertrophic cardiomyopathy (HCM): Unlike AHS, HCM is a genetic disorder that leads to abnormal heart muscle thickening and can cause sudden cardiac arrest. - Arrhythmias: Some athletes might experience benign arrhythmias, but others may have underlying conditions requiring medical attention. - Dilated cardiomyopathy: A pathological enlargement of the heart with impaired function.

Diagnosis

• Electrocardiogram (ECG): Helps identify normal variations and rule out dangerous conditions.
• Echocardiography: Assesses heart structure and function.
• Cardiac MRI: Used in uncertain cases to differentiate between AHS and pathologies.
• Exercise stress test: Confirms the heart’s ability to adapt normally to physical exertion.

Management

AHS requires no treatment as long as it is confirmed to be a benign adaptation. Regular follow-ups are encouraged for professional athletes to monitor any changes over time.

Conclusion

Athletic Heart Syndrome is a beneficial adaptation to strenuous exercise and does not pose health risks. However, proper diagnosis is crucial to exclude underlying heart disease.

Source recommendations

1. American Heart Association Guidelines on Sports and Exercise

1. https://www.heart.org/en/healthy-living/fitness/fitness-basics/aha-recs-for-physical-activity-in-adults
2. https://pubmed.ncbi.nlm.nih.gov/17762377/
3. https://www.heart.org/en/healthy-living/fitness/fitness-basics/aha-recs-for-physical-activity-infographic
4. https://pubmed.ncbi.nlm.nih.gov/17762378/
5. https://www.ahajournals.org/doi/10.1161/circulationaha.107.185649

2. European Society of Cardiology Position Paper on Exercise and Sports Cardiology

1. https://pubmed.ncbi.nlm.nih.gov/26285770/
2. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines/sports-cardiology-and-exercise-in-patients-with-cardiovascular-disease
3. https://pubmed.ncbi.nlm.nih.gov/22582328/
4. https://www.escardio.org/Education/sports-cardiology-resources
5. https://academic.oup.com/eurheartj/article/41/43/4191/5897398