https://mazenz.com/Newsemia/2019/08/13/2018-acc-aha-hrs-guideline-on-the-evaluation-and-management-of-patients-with-bradycardia-and-cardiac-conduction-delay-executive-summary-a-report-of-the-american-college-of-cardiology-american-heart/
2018 ACC/AHA/HRS Guideline on the Evaluation and Management of Patients With Bradycardia and Cardiac Conduction Delay: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines, and the Heart Rhythm Society