The impact of the aortic cusps fusion pattern and valve disease severity on the aortic wall mechanics in patients with bicuspid aortic valve.

The ascending aorta dilatation in the bicuspid aortic valve (BAV) patients is often attributed to congenital abnormalities of the aortic wall, but it may be related to hemodynamic disturbances in the course of BAV disease. At present, ascending aortic diameter is used as almost sole but weak predictor of aortic dissection and rupture in BAV. We examined the association between aortic wall mechanics and severity of aortic valve disease including different cusps fusion patterns using conventional echocardiography and tissue Doppler imaging (TDI). We prospectively studied 106 BAV patients: 72 with right-left (R-L) coronary cusp fusion were matched 1:1 to 34 patients with right-noncoronary (R-N) cusp fusion obtaining 34 pairs of patients. Peak systolic radial velocity and acceleration of the ascending aortic wall, measured by TDI, were used as an index of hemodynamic stress imposed on the aorta. Paired analysis showed higher aortic wall radial velocity (4.71 ± 1.61 cm/s vs. 3.33 ± 1.44 cm/s, p = 0.001) and acceleration (1.08 ± 0.46 m/s2 vs. 0.80 ± 0.34 m/s2, p = 0.015) in-R-L compared to R-N fusion. Pearson correlation showed association of ascending tubular aortic diameter with age (r = 0.258, p = 0.012), weight (r = 0.323, p = 0.001), peak aortic valve gradient (r = 0.386, p = 0.0001), aortic root diameter (r = 0.439, p < 0.0001), and R-N fusion pattern (r = 0.209, p = 0.043). Aortic root diameter was related to male gender (r = 0.296, p = 0.003), weight (r = 0.381, p = 0.0001), ascending aortic diameter (r = 0.439, p < 0.0001), and severity of aortic regurgitation (r = 0.337, p = 0.0009). Regional differences in aortic wall motion between different BAV cusp fusion patterns and association of aortic diameters with the severity of aortic valve disease, both suggest a deleterious hemodynamic impact of cusp fusion patterns and aortic valve dysfunction on ascending aortic wall. Assessment of aortic hemodynamic by TDI is feasible and could be potentially used to improve prediction of acute aortic complications, thus helping to establish optimal timing of aortic surgery in BAV patients.

3D and 2D left ventricular systolic function imaging-- from ejection fraction to deformation. Cardiac resynchronization therapy--substudy.

INTRODUCTION: 3D echocardiography offers options of left ventricular systolic function analysis. The aims of this study are: to assess the usefulness of 3D echocardiography, to test 3D regional measurements (with area strain) among a spectrum of patients and then to check prospectively the value of 3D echocardiography vs 2D in the assessment of response to resynchronization. METHODS: The first retrospective study group comprises 42 subjects: 23 consecutive patients with left ventricular systolic heart failure and 19 healthy control subjects. The left ventricle was assessed by: 2D-Simpson's biplane, 3D-triplane and -automated volumetric method. Next, 24 patients undergoing cardiac resynchronization therapy were prospectively assessed before and after 6 months. A haemodynamic response criterion of 15% left ventricular end-systolic volume (ESV) reduction was used. RESULTS: The 3D volumetric method was the fastest method for left ventricular ejection fraction assessment (bi-33 vs tri-53 vs145 sec, ANOVA P < 0.001). In heart failure the only strain parameter associated with QRS width was global peak longitudinal strain (r = 0.47, P = 0.023). A high agreement in left ventricular ejection fraction and volumes between methods was observed. The following measures select resynchronization candidates in the heart failure group: (1) 3D global longitudinal strain (AUC-0.756; P = 0.022; the cut-off value > -9.52%; 78% sensitivity, 80% specificity), radial strain (AUC-0.739; P = 0.086; cut-off value 20%; 78% sensitivity, 80% specificity) and area strain (AUC-0.733; P = 0.045; cut-off value > -13.5%; 67% sensitivity, 80% specificity). The agreement between the response assessment by Simpson's biplane and 3D was 78% with a negative predictive value of 100%. The lack of global area strain improvement after cardiac resynchronization therapy has a negative predictive value of 100% in the selection of non-responders. CONCLUSIONS: 3D echocardiography is applicable in the assessment of both preserved and reduced left ventricular ejection fraction. This assessment is fast and requires minimal user intervention. 3D strain may help in cardiac resynchronization therapy candidates and response assessment. After cardiac resynchronization, none of the patients were incorrectly identified as responder to cardiac resynchronization therapy by 3D algorithms compared to 2D Simpson's reference.