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Background: Aortic valve neocuspidization (AVNeo) has emerged as a promising aortic valve procedure, and is expected to have a larger effective orifice area (EOA) than commercially available bioprostheses. It is, however, unclear which indices could facilitate left ventricular (LV) reverse remodeling after AVNeo. The aim of this study is to verify the impact of global left ventricular afterload on the LV reverse remodeling following AVNeo., Methods: Data-available consecutive 38 patients (median age, 77; interquartile range, 72.8-82.0) undergoing AVNeo for severe aortic stenosis were enrolled in this study. Preoperative and the last follow-up echocardiographic data were retrospectively analyzed including the valvuloarterial impedance (Zva), a marker of global LV afterload. Reduction in LV geometry index (LVGI) and relative wall thickness (RWT) were used as an indicator for LV reverse remodeling., Results: The Zva reduced in 24 patients (63.2%) during the follow-up period (median, 12 months). Reduction in Zva significantly correlated to improvement of LV geometry (LVGI (r = 0.400, p = 0.013) and RWT (r = 0.627, p < 0.001)), whereas increase in EOA index did not significantly correlate to LVGI (r = 0.009, p = 0.957), or RWT (r = 0.105, p = 0.529)). The reduction in Zva was the multivariate predictor of LV reverse remodeling., Conclusions: Low global LV afterload led to significant LV reverse remodeling even after AVNeo, which could achieve better valve performance than the conventional bioprostheses., (© 2022. The Author(s).)

Background: Conventional indices such as prosthetic valve effective orifice area (EOA) or transvalvular pressure gradients (TPG) may be unreliable in predicting left ventricular (LV) reverse remodeling after aortic valve replacement (AVR). We hypothesized that the global LV afterload, including valvular and arterial impedance, could influence LV reverse remodeling after AVR., Methods: Twenty-three consecutive aortic-stenosis patients (mean age, 76 ± 6.4 years) underwent isolated AVR using contemporary externally wrapped pericardial valves (19 mm, 10 patients; 21 mm 11; 23 mm, 2). Valvuloarterial impedance (Zva), a marker of global LV afterload, was measured on serial echocardiography in addition to indexed EOA, energy loss index (ELI), mean TPG, and stroke work loss. LV mass regression was used as a parameter of LV reverse remodeling., Results: The Zva significantly decreased after AVR (5.05 ± 1.7 mmHg/mL/m 2 , pre-operatively; 3.12 ± 1.0, postoperatively; 3.13 ± 0.89, at last follow-up) in parallel with increased indexed EOA (0.46 ± 0.13 cm 2 /m 2 ; 1.13 ± 0.24; 0.96 ± 0.19), ELI (0.55 ± 0.21 cm 2 /m 2 ; 1.74 ± 0.52; 1.47 ± 0.42), and decreased mean TPG (50.2 ± 19.6 mmHg; 11.1 ± 5.4; 14.7 ± 5.8). The stroke work loss also decreased (26.3 ± 8.5 %; 8.65 ± 4.0; 9.36 ± 3.4). The Zva at last follow-up was significantly correlated with LV mass regression (correlation coefficient, r = - 0.48; P = 0.002), and was a significant predictor of LV reverse remodeling on multiple regression analysis (adjusted odds ratio, -0.43; 95% confidence interval, -31.3 to -0.67, P = 0.042), while indexed EOA, ELI, mean TPG, or systemic arterial compliance were not., Conclusions: The postoperative Zva was significantly associated with LV mass regression after AVR. Maintaining low global LV afterload following AVR may enhance LV reverse remodeling., (© 2017 Wiley Periodicals, Inc.)

A 77-year-old man successfully underwent aortic valve replacement with a bioprosthesis through a right thoracotomy. Right thoracotomy was utilized because the patient had previously undergone esophagectomy with reconstruction of a substernal gastric tube for esophageal cancer as well as total laryngectomy with tracheostoma formation for laryngeal cancer. Thus, even in a situation in which conventional median sternotomy was difficult, a good outcome for aortic valve replacement was achieved through an alternate approach. This case highlights the need to consider patient history when selecting a surgical approach., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

The case is reported of a 65-year-old male who required reoperation for early failure of a Freestyle stentless valve aortic root bioprosthesis implanted using the full root technique. The bioprosthesis had been implanted to treat annuloaortic ectasia associated with severe aortic regurgitation (AR). At 18 months postoperatively, a new diastolic murmur developed, though without complaint by the patient. Transthoracic echocardiography demonstrated severe AR with aneurysmal dilatation of the non-coronary porcine sinus of Valsalva. Pseudoaneurysm formation, associated with perforation of the non-coronary sinus of Valsalva of the bioprosthesis, was observed at surgery. On inspection, the pseudoaneurysm had pushed the commissures inward, and had created severe aortic valve regurgitation. No infection or calcification was detected on the Freestyle valve, and the aortic root was successfully reconstructed using a composite graft.

Background and Aim of the Study: The presence of conformational changes in the aortic root during the cardiac cycle is well known, but precise information on time-related changes at each level of the root is lacking., Methods: High-resolution, 3D sonomicrometry (200 Hz) was applied in an acute sheep model. Twelve crystals were implanted in eight sheep at each base (n = 3), commissure (n = 3), sinotubular junction (n = 3) and ascending aorta (n = 3). Under stable hemodynamic conditions, geometric changes of the perimeter of each sinus of Valsalva, sinus height, and twist and root tilt angles were time-related to left ventricluar (LV) and aortic pressures., Results: Expansion of the perimeter of the three sinuses of Valsalva was homogeneous, but in significantly different proportions (p < 0.001): the right sinus expanded (+32.4 +/- 2.4%) more than the left (+29.3 +/- 3.2%), and more than the non-coronary (NC) sinus (+25.8 +/- 1.7%). A similar pattern was found for aortic root height: right greater than left, and left greater than NC sinus (p < 0.001). This asymmetry resulted in changes of the root's twist and tilt angles. Although the twist deformation was consistent for each sheep, no general pattern was found. The aortic root tilt angle (between the basal plane and the commissural plane) was 16.3 +/- 1.5 degrees at end-diastole (angle oriented posteriorly and to the left). During systole, it was reduced by 6.6 +/- 0.5 degrees, aligning the LV outflow tract with the ascending aorta. This tilt angle returned to its original value after valve closure., Conclusion: Aortic root expansion is asymmetric, generating precise changes in its tilt angle. During systole, tilt angle reduction resulted in a straight cylinder that probably facilitates ejection; during diastole, the tilt angle increased, probably reducing leaflet stress. These findings should impact upon surgical procedures and the design of new prostheses.

Objective: The aortic and mitral valves have been studied in isolation, as if their functions were independent. We hypothesized that both valves work in synchrony on the basis of the shared myocardial pump and orifice., Methods: Six sonometric crystals (7 sheep) were placed in both trigones, the midpoint of the anterior and posterior anulus, and the lateral extremities of the posterior anulus. In a separate series of animals, 3 crystals (8 sheep) were implanted in the aortic annular base of the right, left, and noncoronary sinuses of Valsalva. In an acute, open-chest model, under stable hemodynamic conditions, geometric changes were time related to simultaneous left ventricular and aortic pressures., Results: From mid-diastole to end-systole, the mitral anulus area contracted by -16.1% +/- 1.9% (mean +/- SEM), whereas the aortic base area expanded by +29.8% +/- 3.3% during systole. The mitral anulus deformation was heterogeneous. In systole, the anterior mitral anulus expanded (intertrigonal distance, +11.5% +/- 2.3%) and the posterior mitral anulus contracted (distance between lateral extremities of the posterior anulus, -12.1% +/- 1.5%). The intertrigonal distance corresponded to the base of the left and noncoronary sinus of Valsalva, which expanded similarly during systole (+12.9% +/- 2.0%). The anteroposterior diameter of the mitral anulus was reduced twice that of the transverse diameter. This disparity of reduction can be explained by the posterior displacement of the intertrigonal area corresponding to the systolic aortic root expansion., Conclusions: Mitral anulus deformation is closely related to aortic root dynamics. During systole, the posterior movement of the aortic curtain allows for aortic root expansion, probably to maximize ejection, whereas during diastole, aortic root reduction participates in mitral anulus dilatation. These findings should affect mitral and aortic surgical approaches.

Objectives: The long-term behavior of the pulmonary autograft in the aortic position (Ross procedure) remains uncertain. Using three-dimensional (3D) sonomicrometry (200 Hz) we compared the dynamics of the aortic and pulmonary roots., Methods: Twenty-four crystals were implanted in each aortic (eight sheep) and pulmonary roots (six sheep) at: base (3 x 2), commissures (3 x 2), sinotubular junction (3 x 2), ascending aorta (3) and pulmonary trunk (3). Under stable hemodynamic conditions, geometric changes were time-related to left ventricular pressure (LV) and aortic pressure., Results: The expansion of the aortic root is twice that of the pulmonary root. During the cardiac cycle, the aortic root volume increased by 37.7 +/- 2.7% (mean +/- SEM) versus 20.9 +/- 1.0% for the pulmonary root. Both were cone-shaped at end diastole. Because expansion at commissures was twice that of the base, both roots became more cylindrical during ejection. Although both roots started to expand prior to ejection and reached maximal expansion during the first third of ejection, the commissural and sinotubular junction dynamics were different in each root. While in the aortic root, expansion at commissural and sinotubular junction levels was significantly different (63.7 +/- 3.6% versus 37.0 +/- 2.1%), in the pulmonary root, they were similar (29.0 +/- 1.3% versus 27.7 +/- 1.4%). Expansion of the three sinuses was also different (P<0.001). In the aortic root: the right expanded more than the left and more than the non-coronary sinus. In the pulmonary root: the right sinus expanded more than the anterior more than the left., Conclusions: Dynamic differences might explain the global pulmonary root dilatation when subjected to systemic pressure, particularly at the level of the sinotubular junction which might result in the autograft failure. Differences in the asymmetrical expansion of the aortic and pulmonary roots should be considered for the implantation of the pulmonary autograft in the most physiological position.

Background and Aim of the Study: Aortic valve homografts were treated with 50% ethanol and glycerol followed by freeze-drying (D-Hydro). Comparative results of fresh versus D-Hydro-treated aortic roots implanted for up to nine months in the descending aorta of sheep with induced aortic regurgitation (AR) are reported., Methods: Six fresh and six D-Hydro valves were implanted in 12 sheep for three, six and nine months, and echocardiography and pressures were taken at surgery and sacrifice. Tissue sections were stained with hematoxylin and eosin, von Kossa, Masson's trichrome, Movat's pentachrome, von Willebrand factor, CD3 (a T-cell marker) and smooth muscle alpha-actin., Results: No grafts had increased gradients after implantation, or at sacrifice. At explantation, fresh homografts showed early pannus formation followed by thrombus, annular dilatation and wall calcification. Leaflets were thickened and progressively retracted. All had severe AR. The appearance of D-Hydro-treated homografts was normal, except for mild leaflet retraction in three, resulting in AR (in two animals the induced AR had healed). Histologically, a T-cell-mediated reaction was evident in the fresh homografts, and collagen distortion was noted. Calcification was present in all fresh specimens and was severe at nine months. D-Hydro roots showed only minor calcification in the six-month samples. Normal collagen, and a complete layer of von Willebrand factor-stained cells were present at three months. At nine months, cell rehabitation extended for two-thirds of the leaflets (alpha-actin +). The inflammatory reaction was very mild, with CD3+-stained cells absent in most samples., Conclusion: Aortic valve homografts treated with the D-Hydro freeze-drying method performed better than fresh homografts due to the absence of thrombus and annulus dilatation, limited calcification, and rehabitation of the aortic wall and parts of the leaflet by myofibroblasts, as well as the presence of a complete endothelial layer on the aortic wall and leaflet.

Background and Aim of the Study: Stentless aortic valve bioprostheses have become popular because of their superior hemodynamics and expected increased durability. However, the stentless bioprosthesis differs from stented valves in that glutaraldehyde (GA)-treated tissue is implanted in direct contact with the native aorta. The effect of GA-treated tissue on host tissue has not been reported., Methods: In order to analyze the effect of GA in the healing process, sheep descending aortic conduits treated with 0.625% GA were inserted in the descending thoracic aorta of 10 adult sheep. The implants were removed after 4, 5, 10, 12, 15, 25, 30, 32, 60 and 120 days. The upstream and downstream junctions were evaluated macro- and microscopically, and by immunohistology for smooth muscle cell alpha-actin and von Willebrand factor., Results: By day 60 of implantation, the GA-treated conduits were calcified. By days 60 and 120, the calcification had spread to the host aorta, and was seen as foci of calcification in the junctional area. Acellular areas were also seen in the host aorta near the anastomosis. A fibrotic layer spanning the abluminal aspect of the junction between the implant and host aorta was present at day 4 and continued through 120 days. This layer was characterized by a progressive increase in collagenous matrix and cellularity, as well as new blood vessel formation. The luminal aspect of the junction had a neointimal layer of variable thickness containing alpha-actin-expressing cells covered by a monolayer of von Willebrand factor-expressing cells, seen at 15-30 days and present through 120 days., Conclusion: In our model, implanting GA-fixed tissue in direct contact with living tissues resulted in cell death and calcification of host tissue within 60 days. The integrity of the junction did not appear to be compromised. This may be of interest in light of the increased popularity of the stentless aortic bioprosthesis.

Background and Aim of the Study: The increased use of autologous, homologous or heterologous aortic root demands a detailed knowledge of its anatomy and function. The advent of 3-D digital sonomicrometry offered the opportunity to acquire precise information on the root and leaflet movements during the cardiac cycle., Methods: Under cardiopulmonary bypass, sonomicrometry crystals were implanted in the aortic root and valve of eight sheep. Crystals were sutured at each commissure (n = 3), the top of the sinotubular junction (n = 3), lowest point of the annulus (n = 3), and leaflet tip (n = 3). 3-D coordinates of each crystal were recorded, together with left ventricular and aortic root pressures and ECG. When the animal had returned to a stable hemodynamic condition, the maximum and minimum distances between two crystals, and areas between three crystals, were calculated. Changes in root volume and leaflet position were time-related to the pressure changes., Results: The most significant change between maximum and minimum distance between crystals during the cardiac cycle occurred at the commissural level. Similarly, the triangle defined by the three commissural crystals showed the greatest change in area (47%). The root volume increased by an average of 22%; about 40% of this increase occurred during the isovolumic phase. The aortic leaflets began to open before ejection., Conclusion: We postulate that aortic valve opening is initiated by the outward pull of the commissures. These findings should impact on aortic root surgery.

Objective: Although aortic root expansion has been well studied, its deformation and physiologic relevance remain controversial. Three-dimensional (3-D) sonomicrometry (200 Hz) has made time-related 4-D study possible. Methods: Fifteen sonomicrometric crystals were implanted into the aortic root of eight sheep at each base (three), commissures (three), sinuses of Valsalva (three), sinotubular junction (three), and ascending aorta (three). In this acute, open-chest model, the aortic root geometric deformations were time related to left ventricular and aortic pressures. Results: During the cardiac cycle, aortic root volume increased by mean±1 standard error of the mean (SEM) 33.7±2.7%, with 36.7±3.3% occurring prior to ejection. Expansion started during isovolumic contraction at the base and commissures followed (after a delay) by the sinotubular junction. At the same time, ascending aorta area decreased (−2.6±0.4%). During the first third of ejection, the aortic root reached maximal expansion followed by a slow, then late rapid decrease in volume until mid-diastole. During end-diastole, the aortic root volume re-expanded by 11.3±2.4%, but with different dynamics at each area level. Although the base and commissural areas re-expanded, the sinotubular junction and ascending aorta areas kept decreasing. At end-diastole, the aortic root had a truncated cone shape (base area>commissures area by 51.6±2.0%). During systole, the root became more cylindrical (base area>commissures area by 39.2±2.5%) because most of the significant changes occurred at commissural level (63.7±3.6%). Conclusion: Aortic root expansion follows a precise chronology during systole and becomes more cylindrical – probably to maximize ejection. These findings might stimulate a more physiologic approach to aortic valve and aortic root surgical procedures. [Copyright &y& Elsevier]