Isolated Aortic Valve Replacement in Octogenarians and Septuagenarians: Five-Year Cohort Study

Abstract

Background:Abdominal aortic calcification (AAC)measured on spine X-rays is an established cardiovascular risk factor, though the significance of its presence on dualenergy X-ray absorptiometry (DEXA) is less certain. We set out to determine whether AAC on DEXA is associated with cardiovascular variables, including coronary calcium score and events, in middle-aged men. Methods: Men over 40 years of age from a local randomised trial of calcium supplementation were studied. DEXA was performed at baseline and two-year followup for retrospective AAC assessment using the AAC-8 score. Coronary and aortic calcium scores were assessed by computed tomography (CT). Vascular events including myocardial infarction (MI), stroke (CVA) and sudden death were independently adjudicated. Results: AAC (AAC-8> 0) was present at baseline in 17.2% (57/320) of subjects, and significantly increased to 26%at two years (P< 0.001). Agewas the only independent predictor of baselineAAC (OR=1.06, P< 0.001).Meanpredicted five-year cardiovascular risk (5y-CV) was higher in presence ofAAC (2.5%vs. 1.7%,P< 0.001). AACwas significantly associated with higher CT coronary (P= 0.03) and aortic calcium (P= 0.003) scores. In linear regression models, AAC and coronary calcium score accounted for 8.5% and 19.9%, respectively of the variance of 5y-CV. AACwas significantly associated with MI using survival analysis (HR 5.32, P= 0.04), though did not remain an independent predictor after adjusting for 5y-CV. Conclusion: AAC assessed by DEXA was significantly associated with higher CT coronary and aortic calcium scores and incident myocardial infarction in middleaged men, and therefore can add valuable information regarding cardiovascular risk in this population.