Cardiology of Virginia was started in 1998 by Dr. Mark Johns and it continues today as an independently owned practice. The providers at Cardiology of Virginia take excellent care of their patients and care about their well-being. Our providers are what sets us apart from other practices. We have three providers at our Midlothian, Virginia-based cardiology office, Dr. Mark Johns, Dr. Edson De Guzman, and Katie Hiers, FNP. You can count on our professional providers to care for all your cardiac needs.