Hypertrophic cardiomyopathy (HCM) is a heart disorder marked by excessive thickening of heart muscle. It affects approximately 1 in 500 people and is a genetically transmitted disease. Although patients with HCM can lead long lives without limiting symptoms, the condition is associated with an increased risk of serious health events, including sudden death. This is why it is recommended that relatives of patients diagnosed with HCM are routinely screened for the condition.
There are 2 ways to screen for the disease. One is through genetic testing. It turns out that there are distinct genetic fingerprints which can identify a clear predisposition to the disease. If the relative who was diagnosed with HCM undergoes genetic testing and a fingerprint defect is identified, first degree relatives can be evaluated through the genetic screening route. The advantage of this approach is that it is fairly definitive. The problem is that more than 50% of patients with HCM do not display a distinct genetic marker for the disease - so genetic screening in their relatives is not helpful.
The other way to screen for the disease (as an alternate to genetic screening or in the case where genetic screening was not helpful) is by looking at the hearts of first degree relatives with echocardiograms. The current recommendation is that first degree relatives undergo yearly echocardiograms from age 12 until age 20. After that, if they are participating in competitive athletics, yearly echocardiograms should continue. Otherwise reducing echocardiographic screening to every 5 years until the 6th decade of life is advocated.