These features are weight, height, time of AF onset, LA volume, mitral regurgitation, LVEF, NYHA functional class, tobacco smoking history, previous direct-current shock application attempt, previous transient ischemic attack or stroke, history of heart failure, history of anticoagulation, pulmonary disease including sleep apnea, impaired physical mobility, beta blockers, ACE inhibitors/Angiotensin receptor blockers, and type of anticoagulation. The gene discussed is ACE; the disease is sleep apnea syndrome.