When calcium channel function is impaired, calcium homeostasis is disrupted.Recent studies have shown that Cav1.2, Cav3.3, connexin 43, and RyR2 are highlyexpressed in the pulmonary veins of horses with AF, indicating a link betweencalcium channel dysregulation and AF [96]. This evidence concerns the gene CACNA1I and atrial fibrillation.