IS COLOR-FLOW IMAGING NEEDED TO EXCLUDE CLINICALLY SIGNIFICANT VALVULAR REGURGITATION IN ADULT PATIENTS UNDERGOING TRANSTHORACIC ECHOCARDIOGRAPHY

OBJECTIVE: To establish whether clinically significant aortic and mitr al valvular regurgitation can be excluded in adult patients undergoing transthoracic echocardiography without using colour flow imaging. SET TING: Sunnybrook Health Science Centre, a tertiary referral centre wit h full cardiovascular services affiliated with the University of Toron to, Toronto, Ontario. DESIGN: Logistic regression models were develope d from a retrospective review of 14,051 unselected consecutive echocar diograms from 1991 through 1994. The dependent variable was more than mild aortic or mitral valvular regurgitation. Independent variables in cluded age, sex and various functional and structural measures obtaine d during routine two-dimensional echocardiography. The negative predic tive values and sensitivity of the models were estimated. INTERVENTION : The number of patients correctly classified by these models, as well as the proportion for whom the colour flow imaging did not add to the baseline echocardiogram, was determined. Nonparametric bootstrapping was used to obtain confidence intervals for these statistics. MAIN RES ULTS: Ten models were developed, with negative predictive values rangi ng from 96.2% to 100%. Incorporation of such decision aids into the so ftware of echocardiographic machinery would help echocardiographers to rule out significant aortic or mitral regurgitant lesions. In practic es where colour flow imaging is routinely employed, 40% fewer procedur es could be performed. CONCLUSIONS: Models based on simple demographic and two-dimensional echocardiographic variables can reliably exclude significant valvular regurgitation and could potentially reduce the vo lumes and costs of colour flow imaging. Given the widespread diffusion of colour Doppler imaging, the models may also be helpful to avoid mi sinterpretation of flow imaging results, by defining subgroups in whom the prior probability of significant aortic or mitral regurgitation i s extremely low.