Multidetector Computed Tomography Study of Diameters of the Thoracic Aorta, Abdominal Aorta and Pulmonary Artery in the Offspring and Third Generation Cohorts

Multi-detector CT scanning was conducted using a single General Electric Lightspeed 8 Detector scanner for the primary purpose of detecting and quantifying coronary calcification and thoracic and abdominal aortic calcification. The scanner was located at the Massachusetts General Hospital West Imaging Facility in Waltham, MA. Women < 40 years of age and men < 35 years of age were excluded from the original protocol and pre-menopausal women required a negative screening urine pregnancy test. Subjects were included based upon membership in two generation families and ongoing participation in the Framingham Heart Study. 1200 Offspring Cohort subjects and 1900 selected Gen 3 subjects were included in the original protocol; and an additional 429 subjects were included in the imaging study due to enrollment in an overlapping MDCT study that was part of the NHLBI's Family Heart Study-SCAN study. Therefore, in total, 3529 participants (2111 Third Generation, 1418 Offspring participants) underwent MDCT assessment for coronary and aortic calcium. The CT test was conducted using standard protocols, including two coronary images and one abdominal image. A quantitative CT phantom was placed below the heart and abdomen for each coronary scan and the aortic scan. For the current datasets, the majority of scanned subjects were randomly selected for digital measurement of antero-posterior and transverse diameters of the ascending thoracic aorta at level of the right pulmonary artery, the descending thoracic aorta at the level of the right pulmonary artery, the main pulmonary artery at the level of the right pulmonary artery, the abdominal aorta at two landmarks, one 5cm above the aorto-common iliac bifurcation and the second just above the aorto-common iliac bifurcation. Protocols for imaging, reproducibility, and quality assurance in the Framingham Heart Study were similar or identical to those being used in the Multi-Ethnic Study of Atherosclerosis (MESA) as well as the NHLBI Family Heart Study-SCAN study. Quality control included a daily test of the General Electric scanner. Inter-reader reproducibility for aortic dimension measurements was excellent for readings between two trained physician readers.

In 1948, researchers recruited men and women from the town of Framingham, Massachusetts, beginning the first round of extensive physical examinations and lifestyle interviews that would later be analyzed for common patterns related to CVD development.

Initially, the Framingham Heart Study enrolled 5,209 men and women from the Framingham area who were between the ages of 28 and 62 years. Beginning in 1971, the Framingham Heart Study enrolled 5,124 men and women, who were either offspring of the original cohort or spouses of those offspring. In 2002, 4,095 third generation participants (men and women) were enrolled.

During each clinic exam cycle, the participants undergo a detailed examination including physical examination, medical history, laboratory testing, and electrocardiogram. Over the years, other tests (that may not be performed at every exam cycle) have included pulmonary function, lifestyle, physical function, cognitive function questionnaires, and various noninvasive cardiovascular tests including echocardiograms. The content of each exam cycle differs for Original, Offspring and Generation 3 cohorts and can be found in the Exam Cycle Protocol Manuals.

• Study Weblinks:
  • The Framingham Heart Study
• Study Design:
  • Prospective Longitudinal Cohort
• Study Type:
  • Longitudinal
  • Prospective
• Total number of consented subjects: 3477
• Subject Sample Telemetry Report (SSTR)

Women < 40 years of age and men < 35 years of age were excluded from the original protocol and pre-menopausal women required a negative screening urine pregnancy test. Subjects were included based upon membership in two generation families and ongoing participation in the Framingham Heart Study.

Scanning occurred between June 2002 to April 2005. Interpretation of coronary and aortic calcium measurements was completed in 2006. Interpretation of aortic and pulmonary artery diameter measurements was completed in 2009.

The Generation 1 (or Original) cohort Exam 1 took place between 1948 and 1953. Biennial exams have continued to the present. Exam 29 took place between 2006 and 2007. Exam 30 began in 2008.

The Generation 2 (or Offspring) cohort Exam 1 took place between 1971 and 1975. This cohort on average has been examined every three to four years. However, there was an eight year gap between Exam 1 and Exam 2 and a seven year gap between Exam 7 and Exam 8. Exam 8 took place between 2005 and 2008.

The Generation 3 cohort Exam 1 took place between 2002 and 2005. Exam 2 began in 2008.

The New Offspring Spouse cohort Exam 1 took place between 2003 and 2005. Exam 2 began in 2008.

• Primary Phenotype: Cardiovascular System
• Aorta
• Aortic Aneurysm
• Dissection

• Principal Investigator
  • Christopher J. O'Donnell MD MPH. National heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
• Co-Investigator
  • Udo Hoffmann, MD. Massachusetts General Hospital, Boston, MA, USA.