German Aortic Root Repair Registry-Insights From the First 400 Consecutive Patients.

BACKGROUND: The objective was to provide initial data from our prospective valve-sparing aortic root replacement (V-SARR) registry and reasons for conversion to prosthetic aortic valve replacement. METHODS: Six centers established an intention-to-treat-design V-SARR-registry (the German Aortic Root Repair Registry; first patient in October 2016); the main inclusion criterion was being scheduled for V-SARR as plan A. Clinical information, operative details, intraoperative valve/root measurements, and clinical and transthoracic echocardiography follow-up-data are documented. RESULTS: Of a total of 449 patients, we report data for 401 (81% male; mean age 51 ± 14 years). Overall, 350 patients underwent V-SARR as scheduled, group A (David variants I 55%, III 2%, IV 13%, V 24%, V-Stanford 2%, and Yacoub remodeling 2%); and 51 were converted to aortic valve replacement (group B). Median follow-up was 11 months (range, 0 to 2.6 years), cumulative follow-up was 279 patient-years. In group B, there were fewer connective tissue disorders (6% vs 16%), fewer patients had left ventricular ejection fraction greater than 50% (60% vs 90%), more had bicuspid aortic valves (45% vs 28%), and fewer patients had preoperative none/trace aortic regurgitation (2% vs 20%). Fewer patients in group B had rare types of bicuspid aortic valve (fused N/L, R/N, 10% vs 30%) and more had unbalanced roots (56% vs 40%). Immediate postoperative aortic regurgitation was none/trace in 79% and mild in 20%. At 30 days, the mean transvalvular pressure gradient was 7 ± 5 mm Hg. None of the patients died in hospital; two strokes occurred. One patient needed early aortic valve replacement as redo surgery. CONCLUSIONS: The main factors causing surgeons to convert a planned V-SARR to aortic valve replacement include asymmetry of aortic valve/root, severity of aortic regurgitation, safety reasons (left ventricular ejection fraction), and bicuspid aortic valves (but not rare types). The German Aortic Root Repair Registry will help us identify the impact on long-term outcomes of preoperative and postoperative valvular anatomy and various V-SARR types.

Time-resolved 3-dimensional magnetic resonance phase contrast imaging (4D Flow MRI) reveals altered blood flow patterns in the ascending aorta of patients with valve-sparing aortic root replacement.

OBJECTIVE: The aim of this study was to compare aortic flow patterns in patients after David valve-sparing aortic root replacement with physiologically shaped sinus prostheses or conventional tube grafts in healthy volunteers. METHODS: Twelve patients with sinus prostheses (55 ± 15 years), 6 patients with tube grafts (58 ± 12 years), 12 age-matched, healthy volunteers (55 ± 6 years), and 6 young, healthy volunteers (25 ± 3 years) were examined with time-resolved 3-dimensional magnetic resonance phase contrast imaging (4D Flow MRI). Primary and secondary helical, as well as vortical flow patterns, were evaluated. Aortic arch anatomy as a flow influencing factor was determined. RESULTS: Compared with volunteers, both sinus prostheses and tube grafts developed more than 4 times as many secondary flow patterns in the ascending aorta (sinus prostheses n = 1.6 ± 0.8; tube grafts n = 1.3 ± 0.6; age-matched, healthy volunteers n = 0.3 ± 0.5; young, healthy volunteers n = 0; P ≤ .012) associated with a kinking of the prosthesis itself or at its distal anastomosis. As opposed to round aortic arches in volunteers (n = 16/18), cubic or gothic-shaped arches predominated in patients (n = 16/18, P < .001). In all but 3 volunteers, 2 counter-rotating helices were confirmed in the ascending aorta and were defined as a primary flow pattern. This primary flow pattern did not develop in patients who underwent valve-sparing aortic root replacement. CONCLUSIONS: In patients after valve-sparing aortic root replacement, there was an increased number of secondary flow patterns in the ascending aorta. This seems to be related to surgically altered aortic geometry with kinking. Because flow alterations are known to affect wall shear stress, there seems to be an increased risk for vessel wall remodeling. Compared with previous 4D Flow MRI studies, primary flow patterns in the ascending aorta in healthy subjects were confirmed to be more complex. This underlines the importance of thorough examination of 4D Flow MRI data.

New Device for the Treatment of Functional Ischemic Mitral Regurgitation: Proof of Concept in an In Vitro Model.

BACKGROUND: Optimal surgical treatment of functional ischemic mitral regurgitation (FIMR) is still controversy. Due to the underlying pathophysiology, stand-alone ring annuloplasty is assumed with a high recurrence rate of mitral regurgitation, thus additional subvalvular repair techniques might improve the results. This in vitro study introduces a new device for subvalvular mitral valve repair. METHODS: We developed a new device for subvalvular mitral valve repair, consisting of two frames for papillary muscle (PM) attachment, which are connected with two holding bars serving for fixation of the device on an annuloplasty ring. In the first experimental run, porcine mitral valves including the chordae tendineae and PMs were fixated on a holding device, consisting of a holding ring simulating mitral annulus dilation and height-adjustable frames for PM attachment simulating leaflet tethering. In vitro regurgitant volume was determined in a pulse duplicator. Afterward, the frames for PM attachment were replaced by our newly developed device and the measurements were repeated. RESULTS: In the model simulating FIMR, the regurgitant volume was 44.3 ± 12.38 mL/stroke. After subvalvular reconstruction with our new device, the regurgitant volume was significantly reduced to 33.1 ± 11.68 mL/stroke (p = 0.009). CONCLUSION: In this specific in vitro model, our new device for subvalvular mitral valve reconstruction led to a significant reduction of the regurgitant volume, thus representing a promising technique to potentially improve the results of mitral reconstruction in ischemic functional mitral valve regurgitation. Additional studies are required to further investigate and improve our device.

Significance of an additional unenhanced scan in computed tomography angiography of patients with suspected acute aortic syndrome.

AIM: To assess potential benefits of an additional unenhanced acquisition in computed tomography angiography (CTA) in patients with suspected acute aortic syndrome (AAS). METHODS: A total of 103 aortic CTA (non-electrocardiography-gated, 128 slices) performed due to suspected AAS were retrospectively evaluated for acute aortic dissection (AAD), intramural hematoma (IMH), or penetrating aortic ulcer (PAU). Spiral CTA protocol consisted of an unenhanced acquisition and an arterial phase. If AAS was detected, a venous phase (delay, 90 s) was added. Images were evaluated for the presence and extent of AAD, IMH, PAU, and related complications. The diagnostic benefit of the unenhanced acquisition was evaluated concerning detection of IMH. RESULTS: Fifty-six (30% women; mean age, 67 years; median, 68 years) of the screened individuals had AAD or IMH. A triphasic CT scan was conducted in 76.8% (n = 43). 56% of the detected AAD were classified as Stanford type A, 44% as Stanford type B. 53.8% of the detected IMH were classified as Stanford type A, 46.2% as Stanford type B. There was no significant difference in the involvement of the ascending aorta between AAD and IMH (P = 1.0) or in the average age between AAD and IMH (P = 0.548), between Stanford type A and Stanford type B in general (P = 0.650) and between Stanford type A and Stanford type B within the entities of AAD and IMH (AAD: P = 0.785; IMH: P = 0.146). Only the unenhanced acquisitions showed a significant density difference between the adjacent lumen and the IMH (P = 0.035). Subadventitial hematoma involving the pulmonary trunk was present in 5 patients (16%) with Stanford A AAD. The difference between the median radiation exposure of a triphasic (2737 mGy*cm) compared to a biphasic CT scan (2135 mGy*cm) was not significant (P = 0.135). CONCLUSION: IMH is a common and difficult to detect entity of AAS. An additional unenhanced acquisition within an aortic CTA protocol facilitates the detection of IMH.

Survival and reoperation after valve-sparing root replacement and root repair in acute type A dissection.

OBJECTIVE: Optimal treatment of the dissected root in type A dissection is still controversial. Valve-sparing techniques offer the advantage of better valve performance compared with mechanical valves or bioprostheses. The role of the different valve-preserving methods-root repair and replacement-needs further evaluation. METHODS: Follow-up data (median follow-up, 11.4 years; 95% confidence interval [CI], 10.1-12.7; range, 0-22.1 years) of 179 patients with acute type A dissection and root involvement, who underwent a valve-sparing root replacement using reimplantation (n = 44) or remodeling (n = 39) or a valve-sparing root repair (n = 96) between 1993 and 2017 were analyzed with respect to survival and reoperation. RESULTS: Median age of patients with reimplantation was 56.9 (range, 20.2-78), with remodeling 62.6 (range, 31-79.1), and with valve-sparing root repair 64.5 (range, 31-89.6) years. Thirty-day mortality for these groups was 15.9%, 15.4%, and 12.5% (P = .829), late mortality at 15 years was 43.2% (95% CI, 28.1-66.5), 36.7% (95% CI, 19.7-68.1), and 36.5% (95% CI, 23.0-57.9; P = .504). Risk factors for overall mortality were age, connective tissue disease, total arch replacement, surgical time, cross-clamp time, circulatory arrest, and the reimplantation technique. Cumulative incidence of reoperation at 15 years was 13.4% (95% CI, 2.1-24.7), 20% (95% CI, 6.3-33.6), and 13.3% (95% CI, 4.8-21.7; P = .565), respectively. CONCLUSIONS: With the different conditions in each group in this study on patients with acute type A dissection the valve-preserving root repair technique has similar long-term rates of survival and reoperation compared with root replacement techniques, underlining its usefulness as a less complex and even faster surgical technique if individually indicated.

Valve performance classification in 630 subcoronary Ross patients over 22 years.

OBJECTIVE: To define the function of the "Ross valves" and its clinical meaning in a practical valve performance classification as part of the outcome analysis. METHODS: From 1994 to 2017, 630 consecutive patients underwent the subcoronary Ross procedure at our institution. The valve performance classification combines hemodynamics, symptoms, and management criteria. Median follow-up was 12.5 years (maximum 22.3 years, 7404 patient-years, 99.4% completeness). RESULTS: The mean age of the patients was 44.7 ± 11.9 years. Hospital deaths was 0.3% (n = 2). Twenty years after the operation survival was 73.1% (95% confidence interval [CI], 65.4%-81.6%) and statistically not different from the age- and gender-matched general population; freedom from reoperation was 85.9% (95% CI, 80.2%-92.0%; 0.6% per patient-year), 89.8% (95% CI, 84.3%-95.7%) for autograft, and 91.0% (95% CI, 86.3%-96.0%) for homograft. Preoperative annulus diameter, aortic regurgitation, annulus reinforcement, sinotubular junction reinforcement, and bicuspid aortic valve type were no significant risk factors for reoperation. At 20 years the probability of a patient being in valve performance class I to IV was 5%, 74%, 19%, and 1%, respectively. Time to reoperation was not different in bicuspid and tricuspid aortic valves; preoperative aortic stenosis tended to have better outcome of autograft function. CONCLUSIONS: These up to 22 years data show that the subcoronary Ross procedure continues to provide an excellent tissue aortic valve replacement. The suggested valve performance classification emerged as a practical concept for outcome analysis with the probability of 79% being in the favorable class I or II at 20 years.

A matter of thrombosis: different thrombus-like formations in balloon-expandable transcatheter aortic valve prostheses.

OBJECTIVES: Transcatheter aortic valve implantation is a treatment strategy for degenerated aortic valve prostheses, but there is some concern regarding valve thrombosis. The optimal anticoagulation strategy for implantation of a transcatheter aortic valve prosthesis remains unclear. METHODS: Aortic root models with the Sapien-XT and S3 prostheses (sizes 23 and 26) fixed in a Perimount Magna Ease bioprosthesis (sizes 23 and 25) were constructed. The haemodynamics of the left ventricle were imitated in a proved in vitro model. Milk was used for coagulation after 90s. Different areas of the leaflets (W: wall coagulation, C: commissure coagulation left/right and S: sinus coagulation) were examined and the number of thrombus-like formations was counted. RESULTS: A total of 54% of the thrombus-like formations were found in the sinus, 28% at the wall area, 13% at the right commissure and 10% at the left commissure. Significant differences were detected at the wall area. S3 prostheses had significantly more thrombus-like formations than the XT prostheses. Additionally, in the S3 prostheses, the thrombus-like formation resembled a film whereas in the XT prostheses, the thrombus-like formation was like the crumbs of a cake. We noted exactly the same pattern in explanted prostheses from patients. CONCLUSIONS: The Sapien prostheses tend to form thromboses due to their flow properties. More than half of the thrombus-like formations were seen in the sinus. The S3 prostheses had significantly more thrombus-like formations than the XT prostheses in the wall area. There are different patterns of thrombus-like formations in XT and S3 prostheses used for transcatheter aortic valve implantation both in vivo and in vitro.

Survival and reoperation pattern after 20 years of experience with aortic valve-sparing root replacement in patients with tricuspid and bicuspid valves.

OBJECTIVE: Remodeling or reimplantation are established operative techniques of aortic valve-sparing root replacement. Long-term follow-up is necessary comparing tricuspid and bicuspid aortic valves. METHODS: A total of 315 patients (tricuspid, n = 225, bicuspid, n = 89, quadricuspid, n = 1; remodeling, n = 101, reimplantation, n = 214) were evaluated. Mean follow-up was 10.1 ± 5.6 and 6.4 ± 4.2 years for the remodeling and reimplantation group, respectively. Longest follow-up was 21.9 years with 99.2% completeness. Mean age of the patients was 55.9 ± 14.3 for the remodeling group and 48.9 ± 14.5 years for the reimplantation group. RESULTS: There was no significant difference in survival between the remodeling and reimplantation group (P = .11). Survival was comparable with the normal population in the reimplantation group (P = .33). Risk factors for late death were age, diabetes, and a greater New York Heart Association classification. Cumulative incidence of reoperation at 10 years was 5.8% for the reimplantation and 11.7% for the remodeling group (P = .65). Overall, there was no difference in the cumulative incidence of reoperation between tricuspid and bicuspid aortic valve patients (P = .13); however, a landmark analysis showed that in the second decade, the cumulative incidence of reoperation was greater in bicuspid aortic valve patients (P < .001). A total of 10 of 11 reoperated bicuspid aortic valves were degenerated. CONCLUSIONS: The remodeling and reimplantation aortic valve-sparing root replacement techniques provided excellent long-term survival. Although the number of patients was relatively small, we provide some hints that in the second decade after the operation, especially in bicuspid aortic valve patients, the risk of reoperation may be increased, needing further evaluation.

Mitral valve replacement with the novel TRIBIO and an established stented bioprosthesis in a sheep model.

OBJECTIVES: Heart valve replacement with a bioprosthesis is one of the most frequently performed procedures in cardiac surgery and represents a highly effective therapy to relieve diseased heart valves. Nevertheless, as postoperatively elevated transvalvular gradients and prosthesis-patient mismatch are reported as shortcomings of the procedure or of the currently used devices, there is a need for novel bioprostheses with improved haemodynamics. This study presents preclinical haemodynamic results after mitral valve replacement with the novel TRIBIO bioprosthesis (TRIBIO) compared with an established bioprosthesis in a sheep model. METHODS: Six female sheep had their mitral valves replaced with the TRIBIO and 3 with the Carpentier-Edwards Perimount, both sized 19 mm. The TRIBIO consists of a flexible valve-bearing crown, a force-decoupled interface and an intra-annular base ring. Mean and peak transvalvular gradients as well as an effective orifice area were monitored in both groups using transthoracic echocardiography over the course of the 90-day study. RESULTS: In both groups, haemodynamic performance diminished over time. The TRIBIO demonstrated overall superior haemodynamics, i.e. lower transvalvular gradients and a larger effective orifice area, although the results were not statistically significant. On Day 90, the mean values for the mean and peak transvalvular gradients and the effective orifice area were 6 mmHg, 10.2 mmHg and 1.2 cm2 for the TRIBIO and 10 mmHg, 15.8 mmHg and 0.8 cm2 for the Carpentier-Edwards Perimount, respectively. CONCLUSIONS: This study demonstrates a trend towards improved preclinical haemodynamic performance following mitral valve replacement with the TRIBIO compared to that with an established bioprosthesis in a sheep model.

Ex vivo hydrodynamics after central and paracommissural edge-to-edge technique: A further step toward transcatheter tricuspid repair?

OBJECTIVES: Transcatheter approaches in heart valve disease became tremendously important and are currently established in the aortic position, but transcatheter tricuspid repair is still in its beginning and remains challenging. Replicating the surgical edge-to-edge technique, for example, with the MitraClip System (Abbott Vascular, Santa Clara, Calif), represents a promising option and has been reported successfully in small numbers of cases. However, up to now, few data considering the edge-to-edge technique as a transcatheter approach are available. This study aims to determine the ex vivo hydrodynamics after the central and paracommissural edge-to-edge technique in different pathologies. METHODS: Because of basal or apical dislocation of papillary muscles, leaflet prolapse or tethering was simulated in porcine tricuspid valves mounted on a flexible holding device. Central and paracommissural edge-to-edge techniques were evaluated successively in these pathologies. Regurgitant volume and mean transvalvular gradient were determined in a pulse duplicator. RESULTS: In this ex vivo model, the isolated edge-to-edge technique reduced tricuspid regurgitation. In the prolapse model, regurgitant volume decreased significantly after central edge-to-edge technique (from 49.4 ± 13.6 mL/stroke to 39.3 ± 14.1 mL/stroke). In the tethering model, both the central and the paracommissural edge-to-edge techniques led to a significant decrease (from 48.7 ± 13.9 to 43.6 ± 15.6 and to 41.1 ± 13.8 mL/stroke). In all cases, the reduction of regurgitant volume was achieved at the cost of significantly increased mean transvalvular gradient. CONCLUSIONS: This study provides a reduction of tricuspid regurgitation after the edge-to-edge technique in the specific experimental setup. Whether this reduction is sufficient to treat tricuspid regurgitation successfully in clinical practice remains to be established. Transcatheter approaches need to be evaluated further, probably with regard to concomitant annuloplasty for higher reduction of tricuspid regurgitation.

Rest and exercise haemodynamics in patients with one of two stented bioprostheses and in healthy controls with small aortic annuli.

OBJECTIVES: Because bioprosthetic aortic valve replacement remains one of the most frequent cardiac surgical procedures, it is necessary to study patient haemodynamics in more detail. Until now, a few studies assessed haemodynamics during exercise, but none with special regard to small aortic annuli. We compared patients who had the differently designed bioprostheses, Trifecta and Perimount Magna Ease (PME), size ≤ 23 mm, and a healthy control group during rest and exercise. METHODS: We determined the mean transvalvular gradient, the effective orifice area (EOA) and the EOA index during rest and exercise using transthoracic echocardiography in 35 patients with the Trifecta (mean age 71.4 years, follow-up 1 year, labelled valve size 21.7 mm), in 16 patients with the PME (mean age 66.2 years, follow-up 2.6 years, labelled valve size 21.6 mm) and in 25 healthy persons. The parameters derived were summarized in a simplified Valve Academic Research Consortium-2 classification to determine prosthetic valve dysfunction. RESULTS: When we compared the Trifecta and the PME, a significant superiority of the Trifecta was seen at rest in mean transvalvular gradient (7.96 vs 12.19 mmHg) and EOA (1.57 vs 1.48 cm2), during exercise in all parameters (mean transvalvular gradient 11.06 vs 19.2 mmHg, EOA 1.77 vs 1.26 cm2, EOA index 0.96 vs 0.67 cm2/m2). The Trifecta showed a physiological increase in the EOA index during exercise. Exercise led to a shift to better simplified Valve Academic Research Consortium-2 categories in the Trifecta and to worse in the PME group. CONCLUSIONS: This study reveals the haemodynamic superiority of the Trifecta to the PME. Especially in small aortic annuli, this difference might have some relevance for clinical and research issues.

Longer-term results, z scores, and decision nomograms for treatment of the ascending aorta in 1693 bicuspid aortic valve operations.

OBJECTIVE: This study aims to fine-tune the decision making for ascending aorta treatment in bicuspid aortic valve surgery. METHODS: A total of 1693 patients with a primary indication for aortic valve surgery were investigated retrospectively with respect to a multifactorial decision-making policy including the z score and the clinical outcome in relation to different techniques for ascending aorta treatment (no intervention n = 1116; intervention n = 577 either by ascending aorta replacement n = 404 or aortoplasty n = 173). Follow-up was 99.5% complete (mean 7.0 ± 4.4 years, range 0-17.7 years, 11,895 patient-years). RESULTS: Hospital mortality was 1.2% for the no-intervention group and 0.9% for the intervention group and was not different between groups (P = .629). Survival compared with the adjusted normal population was lower for both groups (no intervention: P < .001) but not by such a great margin for the intervention group (P = .27). Determinants for death were not related to the ascending aorta treatment. Aortoplasty led to significantly more reoperations (P = .002). The z score thresholds for intervention on the ascending aorta were greater for younger patients, intervention was more liberal in young age, depicted in nomograms. CONCLUSIONS: In our study, ascending aorta intervention could be performed with low hospital mortality and obviously did not add to the overall mortality compared with no intervention. Ascending aorta replacement was the most definite intervention. The multifactorial decision for ascending aorta intervention including the z score of the ascending aorta was more liberal in younger patients compared to the simple aortic size guidelines and provided excellent results. However, generalizability needs further data.

First ex vivo and preliminary sheep model results of the new TRIBIO aortic valve bioprosthesis in small aortic annuli.

OBJECTIVES: Small aortic annuli are challenging in aortic valve replacement. Prosthesis-patient mismatch, accompanied by high transvalvular gradients and small orifice area, is an often faced problem impairing postoperative outcome. The new TRIBIO bioprosthesis aims to enable enhanced haemodynamics, being increasingly important with decreasing annular size. This study compares ex vivo hydrodynamics of TRIBIO with 2 established bioprostheses in small annuli at different stroke volumes, simulating 'rest' and 'exercise', and evaluates haemodynamics of TRIBIO in a sheep model. METHODS: Ex vivo: Porcine aortic roots were hardened with glutaraldehyde, approaching the stiffness of decalcified roots. Each bioprosthesis (TRIBIO, Trifecta™, Perimount® Magna Ease), size 19 mm, was implanted in each aortic root and inserted into a pulse duplicator, determining hydrodynamics and geometric orifice area at different stroke volumes (74, 90, 104 ml). Sheep model: Postoperative transvalvular gradients were assessed after implantation of 19 mm TRIBIO in aortic position. RESULTS: Ex vivo: Mean transvalvular gradients were lowest in TRIBIO (7.3, 8.7, 10.2 mmHg at 74, 90, 104 ml) with significant difference to Perimount® Magna Ease. Geometric orifice area in TRIBIO was 2.7 cm2 and significantly larger compared to Perimount® Magna Ease and Trifecta™. Opening of TRIBIO was uniform and apparently complete, whereas leaflet's outward movement was restricted particularly in Perimount® Magna Ease. Sheep model: TRIBIO presented with low transvalvular gradients (δpmean 4.1 ± 2 mmHg, δpmax 7.8 ± 4.6 mmHg), unimpaired leaflet motion and no central or paravalvular leakage. CONCLUSIONS: Ex vivo, the TRIBIO achieved superior hydrodynamics compared to latest generation bioprostheses. These excellent data are supported by very low transvalvular gradients in a preliminary sheep model.

In vitro coronary flow after transcatheter aortic valve-in-valve implantation: A comparison of 2 valves.

BACKGROUND: Transcatheter aortic valve-in-valve implantation (TAVI-ViV) is an evolving treatment strategy for degenerated surgical aortic valve bioprostheses (SAVBs). However, there is some concern regarding coronary obstruction, especially after TAVI-ViV in calcified SAVBs with externally mounted leaflets. We investigated in vitro coronary flow and hydrodynamics after TAVI-ViV using 2 modern SAVBs with externally and internally mounted leaflets. METHODS: Aortic root models including known risk factors for coronary obstruction served for the implantation of SAVBs with either externally mounted leaflets (St Jude Trifecta, size 25) or internally mounted leaflets (Edwards Perimount Magna Ease, size 25). Left and right coronary flow, as well as hydrodynamic parameters, were measured before and after TAVI-ViV with an Edwards Sapien XT transcatheter heart valve, size 23. After the first experimental run, the SAVB leaflets were artificially "calcified," and the measurements were repeated. RESULTS: In both models, noncalcified and calcified, there was no significant reduction in coronary flow with either the Trifecta or the Perimount Magna Ease SAVB. After TAVI-ViV, in the noncalcified model, the mean pressure gradient was increased (Trifecta, P = .0001; Perimount Magna Ease, P = .006) and the geometric orifice area was decreased (P < .001 for both), whereas in the calcified model, the mean pressure gradient was decreased (P < .001 for both) and the geometric orifice area was increased (P < .001 for both). CONCLUSIONS: In our specific model, in noncalcified as well as calcified conditions, TAVI-ViV is feasible with either SAVB (Trifecta or Perimount Magna Ease) without an increased risk of coronary obstruction. Nevertheless, before clinical application of these results, thorough preoperative assessment, considering the different limitations of this model, is mandatory.

Long-Term (up to 21 Years) Follow Up after Biological and Mechanical Aortic Valve Replacement in Younger Patients.

BACKGROUND: Despite the limited durability of biological aortic valves, increasing numbers of younger patients are choosing to receive them, due mainly to the lack of a need for permanent anticoagulation. Few data exist, however, regarding the outcomes of valve replacement in patients aged <55 years, and additional data are required in this patient population. METHODS: Between 1993 and 2014, at the authors' institution, a total of 448 patients (237 males, 101 females; mean age 45.8 ± 8.0 years) underwent aortic valve replacement (AVR) with either a mechanical prosthesis (M1 group, n = 318) or a biological prosthesis (B1 group, n = 130). The mean follow up was 8.5 ± 5.8 years (range: 4 days to 20.8 years) in the M1 group, and 4.9 ± 4.6 years (range: 2 days to 21 years) in the B1 group. The entire collective (EC) (n = 448 patients) was compared and analyzed with a selective collective (SC) (n = 109 patients) after exclusion of patients with concomitant procedures or comorbidities (M2 group, n = 74; B2 group, n = 35). RESULTS: Early mortality was greater after biological AVR in the EC (6.1% versus 1.9%), but in the SC no early deaths were observed after both primary and redo procedures. The reoperation rate was greater after biological AVR in both collectives. The late mortality, survival and endocarditis rates were comparable in both collectives. Bleeding occurred more often in the EC after mechanical AVR. CONCLUSIONS: Biological AVR in patients aged <55 years provides satisfactory outcomes, whereas reoperations were performed less commonly in patients with mechanical valve substitutes. In selective patients, AVR can be performed with zero mortality.

Does Undersizing of Transcatheter Aortic Valve Bioprostheses during Valve-in-Valve Implantation Avoid Coronary Obstruction? An In Vitro Study.

Background The transcatheter aortic valve-in-valve implantation (TAViVI) is an evolving treatment strategy for degenerated surgical aortic valve bioprostheses (SAVBs) in patients with high operative risk. Although hemodynamics is excellent, there is some concern regarding coronary obstruction, especially in SAVB with externally mounted leaflet tissue, such as the Trifecta (St. Jude Medical Inc., St. Paul, Minnesota, United States). We investigated coronary flow and hydrodynamics before and after TAViVI in a SAVB with externally mounted leaflet tissue (St. Jude Medical, Trifecta) with an undersized transcatheter aortic valve bioprosthesis (Edwards Sapien XT; Edwards Lifesciences LLC, Irvine, California, United States) in an in vitro study. Materials and Methods An aortic root model was constructed incorporating geometric dimensions known as risk factors for coronary obstruction. Investigating the validity of this model, we primarily performed recommended TAViVI with the Sapien XT (size 26 mm) in a Trifecta (size 25 mm) in a mock circulation. Thereafter, hydrodynamic performance and coronary flow (left/right coronary diastolic flow [lCF/rCF]) after TAViVI with an undersized Sapien XT (size 23 mm) in a Trifecta (size 25 mm) were investigated at two different coronary ostia heights (COHs, 8 and 10 mm). Results Validation of the model led to significant coronary obstruction (p < 0.001). Undersized TAViVI showed no significant reduction with respect to coronary flow (lCF: COH 8 mm, 0.90-0.87 mL/stroke; COH 10 mm, 0.89-0.82 mL/stroke and rCF: COH 8 mm, 0.64-0.60 mL/stroke; COH 10 mm, 0.62-0.58 mL/stroke). Mean transvalvular gradients (4-5 mm Hg, p < 0.001) increased significantly after TAViVI. Conclusions In our in vitro model, undersized TAViVI with the balloon-expandable Sapien XT into a modern generation SAVB (Trifecta) successfully avoided coronary flow obstruction.

Is the outcome in acute aortic dissection type A influenced by of femoral versus central cannulation?

BACKGROUND: The purpose of this study was to evaluate the single-center experience in initial femoral versus central cannulation of the extracorporeal circulation for acute aortic dissection type A (AADA). METHODS: Between January 2003 and December 2015, 235 patients underwent repair of AADA. All patients were evaluated for the type of arterial cannulation (femoral vs. central) for initial bypass. Demographic data and outcome parameters were accessed. RESULTS: One hundred and twenty seven (54.0%) were initially cannulated in the central aortic vessels (ascending aorta or subclavian/axillary artery) and 108 (46.0%) in the femoral artery. Patients were comparable between age (62.4±14.4 vs. 62.9±14.4 years, P=0.805), gender (male, 62.2 vs. 69.4%, P=0.152) and previous sternotomy (15.7 vs. 16.7%, P=0.861) between both cannulation groups; while EuroSCORE I (11.5±4.0 vs. 12.7±4.2, P=0.031) and ASA Score (3.5±0.81 vs. 3.8±0.57, P=0.011) were significantly higher in the femoral artery cannulation group. Bypass (249±102 vs. 240±81 min, P=0.474), X-clamp (166±85 vs. 157±67 min, P=0.418) and circulatory arrest time (51.6±28.7 vs. 48.3±21.7 min, P=0.365) were similar between the groups as were lowest temperature (18.1±2.0 vs. 18.1±2.2, P=0.775). Postoperative neurologic deficit and 30-day mortality were comparable between both cannulation groups (11.7 vs. 7.2%, P=0.449 and 20.2 vs. 16.9%, P=0.699, central vs. peripheral cannulation). Multivariate analysis revealed only EuroScore I above 13 as single preoperative predictor for mortality. CONCLUSIONS: AADA can be operated with both femoral and central cannulation with similar results. Risk for early mortality was driven by the preoperative clinical and hemodynamic status before operation rather than the cannulation technique.

Time-resolved 3-dimensional magnetic resonance phase contrast imaging (4D Flow MRI) analysis of hemodynamics in valve-sparing aortic root repair with an anatomically shaped sinus prosthesis.

OBJECTIVE: The anatomically shaped sinus prosthesis (Uni-Graft W SINUS; Braun, Melsungen, Germany) used in valve-sparing aortic root replacement promises physiological hemodynamics believed to grant physiologic valve function. Using time-resolved 3-dimensional magnetic resonance phase contrast imaging (4D Flow MRI), we analyzed sinus vortex formation and transvalvular pressure gradients in patients with sinus prosthesis compared with age-matched and young healthy volunteers. METHODS: Twelve patients with sinus prosthesis (55 ± 15 years), 12 age-matched and 6 young healthy volunteers (55 ± 6 years, 25 ± 3 years, respectively) were examined at 3T with a 4D flow magnetic resonance imaging sequence. Sinus vortices visualized by streamlines and time-resolved particle paths were graded on a 4-point Likert scale. Time resolved pressure differences of the left ventricular outflow tract and the ascending aorta to a reference point in the aortic bulb as well as the transvalvular pressure gradient were evaluated. RESULTS: 4D flow visualizations revealed a propensity of the sinus prosthesis toward intermediate (50%) and large (28%) vortices compared with age-matched volunteers with small (61%) and intermediate (36%) vortices. Vortices in sinus prostheses had a similar configuration compared with those in volunteers. The peak transvalvular pressure gradient did not vary significantly between patients and age-matched volunteers (4.0 ± 0.9 mm Hg, 3.8 ± 0.7 mm Hg, P = .373), its temporal evolution resembled that of volunteers with a prolonged positive phase in patients. CONCLUSIONS: Hemodynamics closely relating to those of volunteers were confirmed in sinus prostheses, believed to grant physiological valve function. Minor differences are presumably attributed to graft compliance and temporal resolution of the acquisition. Nevertheless, long-term deterioration of valve function as it was described for straight grafts could potentially be decelerated using sinus prostheses.

Survival and freedom from aortic valve-related reoperation after valve-sparing aortic root replacement in 1015 patients.

OBJECTIVES: The aim of this study was to characterize mortality and aortic valve replacement after valve-sparing aortic root replacement (V-SARR) in a multicentre cohort. METHODS: Between 1994 and 2014, 1015 patients had V-SARR with (n = 288, 28%) or without cusp/commissure repair (n = 727, 72%) at the centres of Lübeck (n = 343, 34%), Stuttgart (n = 346, 34%), Hamburg (n = 109, 11%) and Freiburg (n = 217, 21%), Germany. Comparative survival of an age- and gender-matched general population was calculated. Log-rank tests and multiple logistic regression were used to identify risk factors. RESULTS: The mean follow-up was 5.2 ± 3.9 years. Cumulative follow-up comprised 2933 patient-years. Early survival was 98%. NYHA status and aneurysm size were predictive of death during mid-term follow-up (P = 0.025). Freedom from aortic valve replacement was 90% at 8 years, with the type of V-SARR (root remodelling, David II) being a risk factor (P = 0.015). Bicuspid aortic valve (P = 0.26) and initial valve function (P = 0.4) did not impact reoperation. The need of additional valve repair (cusps/commissures) was not linked to reoperation: freedom from aortic valve replacement at 8 years was 84% if cusp repair was performed versus 90% if V-SARR alone was performed (P = 0.218). Marfan syndrome had no impact on survival or on aortic valve replacement. CONCLUSIONS: Mid-term survival of patients after V-SARR is comparable with that of a matched general population. The regurgitant bicuspid aortic valve is a favourable substrate for V-SARR. Prophylactic surgery should be performed before symptoms or large aneurysms are present to achieve optimal mid-term outcomes.

In vitro investigation of a novel elastic vascular prosthesis for valve-sparing aortic root and ascending aorta replacement.

OBJECTIVES: Prosthetic replacement of the thoracic aorta with common Dacron prostheses impairs the aortic 'windkessel' and, in valve-sparing procedures, also aortic valve function. Elastic graft material may overcome these deficiencies. METHODS: Fresh porcine aortas including the root were set up in a mock circulation before and after replacement of the ascending part with a novel vascular prosthesis providing elastic behaviours. In a first series (n = 14), haemodynamics and leaflet motions of the aortic valve were investigated and also cyclic changes of aortic dimensions at different levels of the root. In a second series (n = 7), intravascular pressure and dimensions of the proximal descending aorta were measured and the corresponding wall tension was calculated. RESULTS: Haemodynamics of the aortic valve remain comparable after replacement. Though the novel prosthesis does not feature such high distensibility as the native aorta, the dynamic of the root was significantly increased compared with common Dacron prostheses at the commissural level, preserving 'windkessel' function. Thus, wall tension of the residual aorta remained unchanged; nevertheless, maximum pressure-time differential dp/dt increased by 13%. CONCLUSIONS: The use of the novel elastic prosthesis for replacement of the ascending aorta seems to be beneficial, especially with regard to the preservation of the aortic windkessel. Further studies will be needed to clarify long-term utilization of the material in vivo.