Abstract 12959: Clinical Utility of Normal Findings on Non-Invasive Cardiac Assessment in a Population-Based Study of Older Adults

Abstract

Introduction: The lack of abnormalities found on noninvasive cardiac testing may improve cardiovascular disease (CVD) risk stratification efforts and convey reduced risk despite the presence of traditional risk factors. Methods: We examined the clinical utility of normal findings on routine noninvasive cardiac assessment in 3,805 (95% white; 61% women) participants from the Cardiovascular Health Study (CHS) without baseline CVD. The combination of normal electrocardiogram (ECG) + normal echocardiogram was assessed for the development of CVD events. Normal ECG was defined as absence of major or minor Minnesota code abnormalities. Normal echocardiogram was defined as absence of contractile dysfunction, wall motion abnormalities, or abnormal left ventricular mass. Cox regression was used to compute the 10-year risk of developing coronary heart disease (CHD), stroke, and heart failure events. Results: There were 1,555 (41%) participants with normal ECG + normal echocardiogram at baseline. During 10 years of follow up, 783 CHD events, 414 strokes, and 576 cases of heart failure were detected. After accounting for traditional cardiovascular risk factors, a protective benefit was observed for all outcomes among participants who had normal ECG + normal echocardiogram (CHD: multivariable HR=0.56, 95%CI=0.46, 0.69; Stroke; multivariable HR=0.57, 95%CI=0.43, 0.76; Heart Failure: multivariable HR=0.36, 95%CI=0.29, 0.41). The addition of normal ECG + normal echocardiogram resulted in significant net reclassification improvement (NRI) of the Framingham risk score for heart failure (risk categories: <10%, 10-20%, >20%; NRI=0.043, 95%CI=0.010, 0.80). Conclusions: Normal findings on the routine ECG and transthoracic echocardiogram identify a group of individuals aged >65 years in which CVD risk is low. Our data support the existence of a low-risk noninvasive cardiac profile and further studies are needed to explore the utility of this profile regarding the decision to implement certain risk factor modification strategies, including invasive measures, to reduce CVD burden in older adults.