Hypertrophic cardiomyopathy screening

HCM is a heart disease in which a portion of the heart becomes thickened without an obvious cause.[5] It affects up to one in 200 people and runs in families.[5] A significant number of people with the condition have no symptoms.[5] Screening is a way of identifying HCM in immediate relatives of family members diagnosed with hypertrophic cardiomyopathy (HCM), and athletes as part of a sports medical.[2] Additional tests may also be performed in those who faint or have exertional chest pain.[2] It aims to detect HCM early, so that interventions can be commenced to prevent complications and sudden cardiac death.[1][4]

Generally, screening may be considered for anyone of any age with a family history of HCM or sudden death.[1] Screening includes at first a history of symptoms or family member with HCM, and a physical examination which may reveal a heart murmur or fourth heart sound.[1] Initial tests include an ECG and 24-hour ambulatory ECG.[1][6] Other tests include echocardiogram, genetic testing and cardiac MRI.[4]

The American Heart Association have developed a 14-point evaluation for competitive athletes, which it recommends for screening healthy teenagers and young adults.[4]

• 
  Flight medical: listening of the chest
• 
  ECG of an athlete
• 
  Child having echocardiogram

In a few well-trained athletes, the normal 10% to 20% increase in left ventricular wall thickness may make it less easy to differentiate an athletic heart from HCM.[4] In HCM, the 12-lead ECG typically shows T wave inversion, ST depression and prominent Q waves, unlike the isolated LVH signs of a normal athletic heart.[4] The ventricular cavity in athletes may also be 10% to 15% greater than in comparable non-athletes.[3]

Particularly for black athletes, some of their ECG characteristics are more likely to cross over with those seen in HCM.[3] If interpreted incorrectly, it has the possibility of leading to being wrongly reassured or even incorrectly diagnosed with HCM leading to being unfairly disqualified.[3] Limited studies mean it is unclear what structural adaptations occur in the hearts of other ethnicities.[3] Limited literature on screening Arab and African male athletes shows a high false positive rate; that is the tests indicate they have the disease when they don't.[7]

HCM has traditionally been of greater interest in Europe, North America, Japan, Israel, and Australia.[8]

As of 2020, research on heart adaptations in females, teenagers and Asian populations is required.[3]