YouTube Star Caleb Logan Dies From Undetected Heart Condition: What Is Hypertrophic Cardiomyopathy?

“The doctor confirmed today that Caleb passed away from a heart condition called Hypertrophic Cardiomyopathy that went undetected in his yearly checkups,” Caleb’s mom Annie writes in an Instagram post. (Photo: Instagram)

Caleb Logan, the 13-year-old who was part of the YouTube-famous family the Bratayleys, died from a heart condition called hypertrophic cardiomyopathy.

Logan’s death sent ripples of sadness throughout the YouTube community when he passed away last month. At the time of his death, his family said in a statement that he had died from an “undetected medical condition.”

Hypertrophic cardiomyopathy occurs when the heart muscle is abnormally thick, which makes it more difficult for the heart to pump blood, according to the Mayo Clinic.

The condition is notoriously undiagnosed because it often doesn’t produce any symptoms. However, for some people, it can lead to chest pain, shortness of breath, and even electrical problems with the heart — which can cause arrhythmia (when the heart’s rhythms are abnormal), the Mayo Clinic says.

The condition can also cause sudden cardiac arrest, according to the American Heart Association.

Around one in 500 people has hypertrophic cardiomyopathy, and it’s about equally common in men and women, the AHA says. It’s typically considered an inherited condition, since it’s caused by gene mutations in the heart muscle proteins. USA Today reports that Caleb’s sisters’ hearts have been checked, and they appear to be healthy.

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