When Cameron meets with Brennan in the Feb. 21 episode of Married at First Sight, he shares details and an update about his health issues. Early in the season we do see Brennan have to step away from the honeymoon to deal with other health problems, but this appears to be different. Cameron tells Brennan that he was diagnosed with atrial flutter, which is a variation of atrial fibrillation (AFib).

AFib is, generally speaking, not life-threatening. However it does involve a rapid and irregular heartbeat.

This can come and go, and according to the National Library of Medicine, it can be brought on by bouts of extreme anxiety and stress. Atrial flutter is similar, but the main difference between the two is that with AFib, the atria in the heart beat irregularly, whereas with atrial flutter, the atria beat faster than is typical.

There are treatment options, like beta blockers, though it's not clear if Cameron opted to take this route. He does, however, admit that he is dealing with it day by day since some days his health is better than others. Though he understands that he won't be biking anytime soon.