2-DIMENSIONAL ECHOCARDIOGRAPHIC ASSESSMENT OF THE PROGRESSION OF AORTIC ROOT SIZE IN 127 PATIENTS WITH CHRONIC AORTIC REGURGITATION - ROLE OF THE SUPRAAORTIC RIDGE AND RELATION TO THE PROGRESSION OF THE LESION

Although aortic root dilation has etiologic and prognostic significanc e in patients with chronic aortic regurgitation (AR), no information i s available regarding changes over time in aortic root size in patient s with the entire spectrum of AR severity or how such changes relate t o progression of the AR or to left ventricular (LV) overload. To analy ze-this, a total of 127 patients with chronic AR who had more than 6 m onths of follow-up by two-dimensional and Doppler echocardiography wer e included in the study (69 men and 58 women; mean age 59.3 +/- 21.2 y ears [range 14 to 94 years]; 67 cases of mild, 45 moderate, 15 severe, and 21 bicuspid aortic valve disease). The aortic anulus, sinuses of Valsalva, supraaortic ridge, and ascending aorta were measured in the parasternal long-axis view, LV volumes were calculated (biplane Simpso n's approach), and the severity of AR was quantified based on proximal jet size and graded according to an algorithm that takes into account major color Doppler criteria. At entry to the study; significant diff erences between patients with mild, moderate, and severe AR were noted only in supraaortic ridge size (1.46 +/- 0.29 cm/m(2) vs 1.63 +/- 0.3 3 cm/m(2) [p < 0.006]; vs 1.67 +/- 0.43 cm/m(2) [p < 0.03]). A signifi cant increase in aortic root size at all levels was observed during th e follow-up period in all three groves of severity of AR. The rate of change of the supraaortic ridge, the upper support structure of the an ulus and cusps, was foster in patients with more severe degrees of AR (p = 0.013); this was not the case at the other aortic levels. No diff erences-were observed in aortic root size or rate of progression betwe en patients with bicuspid or tricuspid aortic valves. Patients were co nsidered ''progressive'' if they lay on the steepest positive segment of the curve representing the rank order in the rate of aortic root pr ogression. Compared with ''nonprogressive'' patients, patients who wer e progressive in suproaortic ridge size (rate >0.12 cm/yr; n = 23) had a faster rate of progression in the degree of regurgitation as assess ed by the regurgitant jet area/LV outflow tract area ratio measured in the parasternal short-axis view (0.48 +/- 0.45 vs 0.24 +/- 0.5/yr; p < 0.03) and a faster rate of progression of LV end-diastolic volume (3 0 +/- 22.8 vs 14.4 +/- 15.6 ml/yr; p < 0.0002) and LV mass (70.8 +/- 7 4.4 vs 16.8 +/- 19.2 gm/yr.; p < 0.0004). In conclusion, there is prog ressive dilation of the aortic root at all levels, even in patients wi th mild AR. More rapid progression in aortic root size is associated w ith more rapid progression of the underlying aortic insufficiency, as well as more rapid increases in LV volume and mass.