Several authors consider the following as predictors of recurrence: age, use of angiotensin-converting enzyme inhibitors (ACE inhibitors), angiotensin II receptor blockers (ARBs), spironolactone, comorbidities, time of evolution of AF, increased diameter and atrial volumes, and low peak velocity of the left atrial appendage, among others [23–33]. The gene discussed is ACE; the disease is atrial fibrillation.