Aortic calcium, aortic valve calcium (AVC), and coronary artery calcium
(CAC) have been associated with cardiovascular event risk. We examined
the prevalence of thoracic aortic calcium (TAC) and AVC in relation to
the presence and extent of CAC, cardiovascular risk factors, and
estimated risk of coronary heart disease (CHD). In 2,740 persons
without known CHD aged 20 to 79 years, CAC was assessed by electron
beam- or multidetector-computed tomography. We determined the
prevalence of TAC and AVC in relation to CAC, CHD risk factors, and
predicted 10-year risk of CHD. A close correspondence of TAC and AVC
was observed with CAC. TAC and AVC increased with age; by the eighth
decade of life, the prevalence of TAC was similar to that of CAC
(>80%), and 36% of men and 24% of women had AVC. Age, male gender,
and low-density lipoprotein cholesterol were directly related to the
likelihood of CAC, TAC, and AVC; higher diastolic blood pressure and
cigarette smoking additionally predicted CAC. Body mass index and
higher systolic and lower diastolic blood pressures were also related
to TAC, and higher body mass index and lower diastolic blood pressure
were related to AVC. Calculated risk of CHD increased with the presence
of AVC and TAC across levels of CAC. TAC and AVC provided incremental
value over CAC in association with the 10-year calculated risk of CHD.
If longitudinal studies show an incremental value of aortic and aortic
valve calcium over that of CAC for prediction of cardiovascular events,
future guidelines for risk assessment incorporating CAC assessment may
additionally incorporate the measurement of aortic and/or aortic valve
calcium. |