My brother is 47 and had afib twice. Once they chemically cardioverted him and the second time they used a shock.
His doctor is diagnosing it as thyrotoxicosis.
His is Free t3 was 3.8 (ref 2.0-3.5) and now went up to 4.1. His Free t4 was 1.1 (ref 0.9-1.7)
Does anyone have experience with this? Does a slightly elevated t3 = thyrotoxicosis
He is on androgel, and opiates for Chronic pain.