Two-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 significance in patients with chronic aortic regurgitation (AR), no information is available regarding changes over time in aortic root size in patients with the entire spectrum of AR severity or how such changes relate to progression of the AR or to left ventricular (LV) overload. To analyze this, a total of 127 patients with chronic AR who had more than 6 months of follow-up by two-dimensional and Doppler echocardiography were included in the study (69 men and 58 women; mean age 59.3 +/- 21.2 years [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 Simpson'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 differences between patients with mild, moderate, and severe AR were noted only in supraaortic ridge size (1.46 +/- 0.29 cm/m2 vs 1.63 +/- 0.33 cm/m2 [p < 0.006]; vs 1.67 +/- 0.43 cm/m2 [p < 0.03]). A significant increase in aortic root size at all levels was observed during the follow-up period in all three groups of severity of AR. The rate of change of the supraaortic ridge, the upper support structure of the anulus and cusps, was faster in patients with more severe degrees of AR (p = 0.013); this was not the case at the other aortic levels. No differences were observed in aortic root size or rate of progression between patients with bicuspid or tricuspid aortic valves. Patients were considered "progressive" if they lay on the steepest positive segment of the curve representing the rank order in the rate of aortic root progression. Compared with "nonprogressive" patients, patients who were progressive in supraaortic ridge size (rate >0.12 cm/yr; n = 23) had a faster rate of progression in the degree of regurgitation as assessed 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 foster rate of progression of LV end-diastolic volume (30 +/- 22.8 vs 14.4 +/- 15.6 ml/yr; p < 0.0002) and LV mass (70.8 +/- 74.4 vs 16.8 +/- 19.2 gm/yr; p < 0.0004). In conclusion, there is progressive dilation of the aortic root at all levels, even in patients with mild AR. More rapid progression in aortic root size is associated with more rapid progression of the underlying aortic insufficiency, as well as more rapid increases in LV volume and mass.

Doppler echocardiographic assessment of progression of aortic regurgitation.

The rate of progression of the degree of chronic aortic regurgitation (AR) is unknown. Furthermore, although left ventricular (LV) dilation has been studied in patients with severe AR, its rate and determining factors, and specifically, its relation to the degree of regurgitation remain to be established and have not previously been studied for mild and moderate AR. The purpose of this study was to explore the progression of chronic AR by 2-dimensional and Doppler echocardiography, and the relation of LV dilation to the fundamental regurgitant lesion and its progression in patients with a full spectrum of initial AR severity. We studied 127 patients with AR by 2-dimensional and Doppler echocardiography (69 men; 59 +/- 21 years; 67 with mild, 45 with moderate, 15 with severe AR). AR increased in 38 patients (30%) (25% of mild, 44% of moderate, and 50% of moderate to severe lesions; p <0.006). The ratio of proximal AR jet height to LV outflow tract height also increased (30.3 +/- 17.5% vs 35.2 +/- 19.7%; p <0.0001). Initial LV volumes and mass were larger in patients with more severe AR and increased significantly during follow-up (138 +/- 53 to 164 +/- 70 ml; 59 +/- 32 to 71.7 +/- 42 ml; 203 +/- 89 to 241 +/- 114 g; p <0.0001). LV volumes and mass increased faster in patients with more severe AR, and in those in whom the degree of AR progressed more rapidly. Finally, patients with bicuspid aortic valve (n = 21) had a higher prevalence of severe AR than patients with tricuspid aortic valves (52% vs 4%; p <0.001). In conclusion, AR is a progressive disease not only in patients with severe AR but also in those with mild and moderate regurgitation. Patients with more severe AR have larger left ventricles that also dilate more rapidly.

Doppler echocardiographic assessment of long-term progression of mitral stenosis in 103 patients: valve area and right heart disease.

OBJECTIVES: The purpose of this study was to determine, in a large referral population, the rate of echocardiographic change in mitral valve area (MVA) without interim intervention, to determine which factors influence progression of narrowing and to examine associated changes in the right side of the heart. BACKGROUND: Little information is currently available on the echocardiographic progression of mitral stenosis, particularly on progressive changes in the right side of the heart and the ability of a previously proposed algorithm to predict progression. METHODS: We studied 103 patients (mean age 61 years; 74% female) with serial two-dimensional and Doppler echocardiography. The average interval between entry and most recent follow-up study was 3.3 +/- 2 years (range 1 to 11). RESULTS: During the follow-up period, MVA decreased at a mean rate of 0.09 cm2/year. In 28 patients there was no decrease, in 40 there was only relatively little change (< 0.1 cm2/year) and in 35 the rate of progression of mitral valve narrowing was more rapid (> or = 0.1 cm2/year). The rate of progression was significantly greater among patients with a larger initial MVA and milder mitral stenosis (0.12 vs. 0.06 vs. 0.03 cm2/year for mild, moderate and severe stenosis, p < 0.01). Although the rate of mitral valve narrowing was a weak function of initial MVA and echocardiographic score by multivariate analysis, no set of individual values or cutoff points of these variables or pressure gradients could predict this rate in individual patients. There was a significant increase in right ventricular diastolic area (17 to 18.7 cm2) and tricuspid regurgitation grade (2 + to 3 +; p < 0.0001 between entry and follow-up studies). Progression in right heart disease occurred even in patients with minimal or no change in MVA. Patients with associated aortic regurgitation had a higher rate of decrease in MVA than did those with trace or no aortic regurgitation (0.19 vs. 0.086 cm2/year, p < 0.05). CONCLUSIONS: The rate of mitral valve narrowing in individual patients is variable and cannot be predicted by initial MVA, mitral valve score or transmitral gradient, alone or in combination. Right heart disease can progress independent of mitral valve narrowing.

Quantitative assessment of stenotic aortic valve area by using intracardiac echocardiography: in vitro validation and initial in vivo illustration.

Quantitative assessment of aortic stenosis (AS) is subject to the limitations of all current noninvasive and invasive methods. The ability to obtain a direct measure of aortic valve area with high resolution by intracardiac echocardiography (ICE) could be of great benefit to catheterized patients. To provide a fixed AS area as an ideal standard for comparison, we performed ICE in 12 sheep hearts with experimentally created AS and five human AS hearts from autopsies. ICE catheters were passed retrograde across the aortic valve, and the minimal orifice area on pullback was planimetered and compared with calibrated video imaging. The entire orifice circumference could be successfully recorded in 16 (94%) hearts. Orifice area from ICE correlated well with actual values (r=0.98; standard error of the estimate [SEE] = 0.06 cm2). To illustrate the applicability in vivo, two canine models and 10 patients with AS were studied. The limiting orifice could be imaged in both animals and in 8 of 10 patients, in whom values agreed well with invasive data (r= 0.95; SEE = 0.04 cm2). ICE can therefore accurately measure AS orifice area in vitro; it can be applied in vivo as well. These validation studies laid the foundation for subsequent clinical studies and applications.

Intracardiac ultrasonographic assessment of atrial septal defect area: in vitro validation and technical considerations.

Assessment of atrial septal defect (ASD) size and shape is important for planning and guiding its transcatheter occlusion and can potentially be achieved by intracardiac ultrasonography (ICUS). ICUS accuracy, however, must first be established against stable standards and technical imaging requirements defined. We therefore used 10, 20, and 30 MHz ICUS catheters to examine 17 ASDs that were 0.16 to 6.7 cm2 in area and were surgically created in excised ovine hearts with 10, 20, and 30 MHz ICUS catheters. ASD shape and area by ICUS were compared with direct video images of the actual ASD. In all instances minimal area by ICUS pullback agreed well with actual values (y = 1.04x + 0.2, SEE = 0.23 cm2, r = 0.99) and corresponded well with defect shapes. The maximum angle between ultrasonography beam and septal plane allowing for complete ASD visualization was 20 degrees. The angle depended on transducer frequency and septal thickness. This new technique has potential value for the accurate assessment of ASD shape and size and may be especially useful in the setting of transcatheter occlusion.