Cardiovascular Specialists of Central Maryland 10710 Charter Dr, Ste 400 Columbia, MD 21044 Google Map. Phone: 410-997-7979 Appt: 443-276-6050 Fax: 410-997-9231 Practice Hours. Echo and nuclear stress testing appointments are available beginning at 7:30 a.m., vascular testing at 8 a.m., and office visit appointments at 8:30 am..