Background: With the advent of color Doppler echocardiography, which can detect even a trivial aortic regurgitation (AR), the spectrum of the audible cardiac murmurs caused by AR which presents specific and characteristic findings should receive further refinement.
Methods: Twenty-eight subjects with isolated AR (21 male and 7 female, mean age 61 +/- 41 yrs) diagnosed by colour Doppler echocardiography (15 mild, 6 moderate, and 7 severe by Nanda's criteria) and 8 normal controls (5 male and 3 female, mean age 38 +/- 15 yrs) were randomly invited for a physical examination to evaluate the systolic and diastolic murmurs in four auscultation areas by two experienced cardiologists who were blind to the clinical profile of each patient. Subsequently, a complete and comprehensive echocardiographic examination was performed to measure the transaortic peak velocity and time velocity integral, aortic root diameter, stroke volume, peak diastolic velocity and pressure half time of the AR jet, fractional shortening, and left ventricular systolic and diastolic internal dimensions.
Results: Systolic murmur was present in 62.5%, 66.7%, 100% and 100% of subjects with no, mild, moderate and severe AR, respectively. The corresponding numbers for diastolic murmur were 12.5%, 13.3%, 100% and 100% in subjects with no, mild, moderate and severe AR, respectively. The corresponding numbers for diastolic murmur were 12.5%, 13.3%, 100% and 100%. Multivariate analyses revealed that only the high peak aortic flow velocity was a significant determinant of systolic murmur. High grade AR, low diastolic blood pressure, high peak velocity of the AR jet and high systolic blood pressure were significant determinants of diastolic murmur.
Conclusions: Both systolic and diastolic murmurs can be heard in most patients with moderate to severe AR. In contrast, a large proportion of subjects with mild AR have systolic murmur alone.