Searches were free texts and included the following keywords: “high fat diet,” “ion channel,” “obesity,” “metabolic syndrome,” “LQTS,” “atrial fibrillation,” “dyslipidemia,” “cardiac calcium channel,” “cardiac potassium channel,” “cardiac sodium channel,” “Ca handling proteins,” “NCX,” “pro-inflammatory cytokines,” “insulin,” “leptin,” “hyperglycemia,” and “hyperuricemia.” Despite our thorough search, it is also possible that we may have missed relevant studies including non–English language studies. This evidence concerns the gene KCNA4 and atrial fibrillation.