Patient Population, Recruitment, and Consent:

Patients presenting to the Houston Methodist DeBakey CMR Laboratory will be enrolled from April 2008 to April 2038. It is expected that up to 100,000 patients may be enrolled during this period.

Subjects will be identified based on their referral to the Houston Methodist DeBakey CMR Laboratory for MRI studies during the proposed study period.

After enrollment, a registered nurse or physician will perform a thorough structured patient interview and/or review of electronic health records to document baseline medical history including cardiac risk factors, symptoms, medication usage, and prior procedure history. A small blood sample will be drawn and stored for future biomarker and/or genetic testing analysis. Annual follow up for clinical status will be performed via review of electronic health records; structured telephone interviews with the patients, relatives, and/or their health care providers; and/or the social security death index database.