Angiotensin converting enzyme inhibitors, angiotensin II type 1 receptor antagonists and pirfenidone have been shown to be effective in attenuating arrhythmogenic atrial remodeling, resulting in a marked reduction in atrial fibrosis, with reduced conduction heterogeneity and AF vulnerability (Li et al., 2001; Kumagai et al., 2003; Lee et al., 2006). The gene discussed is AGTR1; the disease is atrial fibrillation.