Transcatheter heart valve explant with infective endocarditis-associated prosthesis failure and outcomes: the EXPLANT-TAVR international registry.

BACKGROUND AND AIMS: Surgical explantation of transcatheter heart valves (THVs) is rapidly increasing, but there are limited data on patients with THV-associated infective endocarditis (IE). This study aims to assess the outcomes of patients undergoing THV explant for IE. METHODS: All patients who underwent THV explant between 2011 and 2022 from 44 sites in the EXPLANT-TAVR registry were identified. Patients with IE as the reason for THV explant were compared to those with other mechanisms of bioprosthetic valve dysfunction (BVD). RESULTS: A total of 372 patients from the EXPLANT-TAVR registry were included. Among them, 184 (49.5%) patients underwent THV explant due to IE and 188 (50.5%) patients due to BVD. At the index transcatheter aortic valve replacement, patients undergoing THV explant for IE were older (74.3 ± 8.6 vs. 71 ± 10.6 years) and had a lower Society of Thoracic Surgeons risk score [2.6% (1.8-5.0) vs. 3.3% (2.1-5.6), P = .029] compared to patients with BVD. Compared to BVD, IE patients had longer intensive care unit and hospital stays (P < .05) and higher stroke rates at 30 days (8.6% vs. 2.9%, P = .032) and 1 year (16.2% vs. 5.2%, P = .010). Adjusted in-hospital, 30-day, and 1-year mortality was 12.1%, 16.1%, and 33.8%, respectively, for the entire cohort, with no significant differences between groups. Although mortality was numerically higher in IE patients 3 years postsurgery (29.6% for BVD vs. 43.9% for IE), Kaplan-Meier analysis showed no significant differences between groups (P = .16). CONCLUSIONS: In the EXPLANT-TAVR registry, patients undergoing THV explant for IE had higher 30-day and 1-year stroke rates and longer intensive care unit and hospital stays. Moreover, patients undergoing THV explant for IE had a higher 3-year mortality rate, which did not reach statistical significance given the relatively small sample size of this unique cohort and the reduced number of events.

Deformation of Transcatheter Aortic Valve Prostheses: Implications for Hypoattenuating Leaflet Thickening and Clinical Outcomes.

BACKGROUND: Although transcatheter aortic valve replacement (TAVR) therapy continues to grow, there have been concerns about the occurrence of hypoattenuating leaflet thickening (HALT), which may affect prosthesis function or durability. This study aimed to examine prosthesis frame factors and correlate their extent to the frequency of HALT and clinical outcomes. METHODS: We prospectively examined 565 patients with cardiac computed tomography screening for HALT at 30 days after balloon-expandable SAPIEN3 and self-expanding EVOLUT TAVR. Deformation of the TAVR prostheses, asymmetric prosthesis leaflet expansion, prosthesis sinus volumes, and commissural alignment were analyzed on the postprocedural computed tomography. For descriptive purposes, an index of prosthesis deformation was calculated, with values >1.00 representing relative midsegment underexpansion. A time-to-event model was performed to evaluate the association of HALT with the clinical outcome. RESULTS: Overall, HALT was present in 21% of SAPIEN3 patients and in 16% of EVOLUT patients at 30 days after TAVR. The occurrence of HALT was directly associated with greater prosthesis frame deformation (P<0.001), worse asymmetry of the leaflets (P<0.001), and smaller TAVR neosinus volumes (P<0.001). These relations were present in both prosthetic types and in all of their size ranges (all P<0.05). In multivariable analyses that include clinical variables previously associated with HALT (eg, anticoagulant therapy), variables of TAVR prosthesis deformation remained predictive of HALT. Although HALT was not associated with changes in prosthetic hemodynamics, its presence was associated with the risk of mortality at 1 year, with respect to greater incidences of all-cause mortality (hazard ratio, 2.98 [95% CI, 1.57-5.63]; P=0.001), cardiac death (hazard ratio, 4.58 [95% CI, 1.81-11.6]; P=0.001), and a composite outcome of all-cause mortality and heart failure hospitalization (hazard ratio, 1.94 [95% CI, 1.14-3.30]; P=0.02) with adjustment for age, sex, and comorbidities. CONCLUSIONS: Nonuniform expansion of TAVR prostheses resulting in frame deformation, asymmetric leaflet, and smaller neosinus volume is related to occurrence of HALT in patients who undergo TAVR. These data may have implications for both prosthesis valve design and deployment techniques to improve clinical outcomes for these patients.

Association of transcatheter edge-to-edge repair with improved survival in older patients with severe, symptomatic degenerative mitral regurgitation.

BACKGROUND: Randomized clinical trials demonstrated transcatheter edge-to-edge repair (TEER) efficacy in improving outcome vs. medical management for functional mitral regurgitation, but limited randomized data are available for the treatment of degenerative mitral regurgitation (DMR). We aimed to compare the outcome of older patients treated with TEER vs. unoperated DMR. METHODS AND RESULTS: Registries including consecutive patients ≥65 years with symptomatic severe DMR treated with TEER (MitraSwiss and Minneapolis Heart Institute registries) or unoperated (MIDA registry) were analysed. Survival was compared overall and after matching for age, sex, EuroSCORE II, and ejection fraction. The study included 1187 patients (872 treated with TEER and 315 unoperated). During 24 ± 17 months of follow-up, 430 patients died, 18 ± 1% at 1 year and 50 ± 2% at 4 years. Patients undergoing TEER had similar age (82 ± 6 vs. 82 ± 7 years) and sex to unoperated patients, but higher surgical risk/comorbidity (EuroSCORE II 3.98 ± 4.28% vs. 2.77 ± 2.46%), more symptoms, and atrial fibrillation (P < 0.0001). Transcatheter edge-to-edge repair was associated with lower mortality accounting for age, sex, EuroSCORE II, New York Heart Association class, atrial fibrillation, and ejection fraction [hazard ratio (HR): 0.47, 95% confidence interval (CI): 0.37-0.58; P < 0.0001]. After propensity matching (247 pairs of patients), TEER consistently showed better survival compared with unoperated patients (49 ± 6% vs. 37 ± 3% at 4 years, P < 0.0001) even in comprehensive multivariable analysis (HR: 0.60, 95% CI: 0.40-0.91; P = 0.03). Procedural failure was infrequent but post-procedural mitral regurgitation, remaining moderate-to-severe in 66 (7.6%) patients, was associated with excess mortality vs. trivial residual regurgitation (30 ± 6% vs. 11 ± 1% at 1 year, P < 0.0001). CONCLUSION: Amongst older patients with severe symptomatic DMR at high surgical risk, mitral TEER was associated with higher survival vs. unoperated patients. Successful control of mitral regurgitation was key to survival improvement with mitral TEER, which should be actively considered in patients deemed inoperable.

Re-Dosing del Nido cardioplegia in adult cardiac surgery: Perfusion characteristics and outcomes--Is there an optimal redosing strategy?

OBJECTIVES: del Nido cardioplegia is utilized for myocardial protection in adult patients undergoing cardiac surgery; however, no standardized re-dosing protocol exists. We describe perfusion characteristics and clinical outcomes in adult cardiac surgery patients who were re-dosed with del Nido cardioplegia. METHODS: Chart review was performed for adult patients undergoing cardiac surgery (specific inclusion/exclusion criteria below) who received exactly two doses of del Nido cardioplegia from 2012 to 2019; n = 542 patients. The main outcome was a composite endpoint comprised of operative mortality, myocardial infarction, post-operative cardiac support device (CSD), and postoperative decrease in ejection fraction (EF), which was analyzed via multivariable logistic regression (MVLR). A secondary analysis evaluated postoperative vasoactive-inotropic scores (VIS) via gamma log link regression (GLLR) as a more physiologic indication of myocardial recovery. RESULTS: MVLR demonstrated that increased total cardiopulmonary bypass (CPB) time was associated with a positive composite outcome (p < .001), whereas time between doses (p = .237) and the volume of each dose was not (p = .626). GLLR also demonstrated that prolonged CBP, decreased EF, congestive heart failure at time of surgery, and low hematocrit at the start of the surgery were all associated with higher VIS. CONCLUSIONS: In this retrospective study, variations in re-dosing strategy for del Nido cardioplegia do not affect postoperative outcomes and increased CPB time is associated with increased operative mortality, myocardial infarction, need for post-operative CSDs, and reduced postoperative EF, and increased VIS, irrespective of the re-dosing strategy. Further studies are warranted to to identify additional patient and operative characteristics that predispose to complications.

Saphenous Vein Graft Failure: From Pathophysiology to Prevention and Treatment Strategies.

Saphenous vein grafts (SVGs) remain the most frequently used conduits in coronary artery bypass graft surgery (CABG). Despite advances in surgical techniques and pharmacotherapy, SVG failure rates remain high, often leading to repeat coronary revascularization. The no-touch SVG harvesting technique (minimal graft manipulation with preservation of vasa vasorum and nerves) reduces the risk of SVG failure, whereas the effect of the off-pump technique on SVG patency remains unclear. Use of buffered storage solutions, intraoperative graft flow measurement, careful selection of the target vessels, and physiological assessment of the native coronary circulation before CABG may also reduce the incidence of SVG failure. Perioperative aspirin and high-intensity statin administration are the cornerstones of secondary prevention after CABG. Dual antiplatelet therapy is recommended for off-pump CABG and in patients with a recent acute coronary syndrome. Intermediate (30%-60%) SVG stenoses often progress rapidly. Stenting of intermediate SVG stenoses failed to improve outcomes; hence, treatment focuses on strict control of coronary artery disease risk factors. Redo CABG is associated with higher perioperative mortality compared with percutaneous coronary intervention (PCI); hence, the latter is preferred for most patients requiring repeat revascularization after CABG. SVG PCI is limited by high rates of no-reflow and a high incidence of restenosis during follow-up. Drug-eluting and bare metal stents provide similar long-term outcomes in SVG PCI. Embolic protection devices reduce no-reflow and should be used when feasible. PCI of the corresponding native coronary artery is associated with better short- and long-term outcomes and is preferred over SVG PCI, if technically feasible.

Impact of inferior vena cava entry characteristics on tricuspid annular access during transcatheter interventions.

OBJECTIVES: The purpose of this study was to characterize the anatomic relationship between the inferior vena cava (IVC) and tricuspid annulus (TA) and its potential impact on the performance of transcatheter TV interventions. BACKGROUND: Transcatheter tricuspid valve (TV) interventions are emerging as a therapeutic alternative for the treatment of severe, symptomatic tricuspid regurgitation (TR). Progression of TR is associated with right heart dilatation. These anatomic changes may distort the IVC-TA relationship and impact successful implantation of transcatheter devices. METHODS: Fifty patients who presented with symptomatic TR for consideration of transcatheter TV therapy with an available CT were included in the study. Comprehensive transesophageal echocardiogram and CT analyses were performed to assess the right-sided cardiac chambers, TA and IVC-TA relationship. RESULTS: The mean age of the study cohort was 78.4 ± 8.9 years. Torrential TR was present in 54% (n = 27). There was considerable variation in the short axis mid-IVC to mid-TA offset (SAXMID 18.2 ± 7.9 mm, range 4.7-42.1 mm). CONCLUSIONS: The IVC-to-TA relationship exhibits significant variability in patients with symptomatic TR. CT analysis of the tricuspid anatomy, including the relationship to the surrounding structures and the IVC, is essential for planning transcatheter TV interventions. Further studies are needed to define whether the IVC-to-TA relationship is a predictor of technical success in the context of specific transcatheter delivery systems.

Anatomic classification of mitral annular calcification for surgical and transcatheter mitral valve replacement.

BACKGROUND AND AIM OF THE STUDY: A systematic approach to quantify mitral annular calcification (MAC) in all-comers by multidetector computed tomography (MDCT) is essential to guide treatment, but lacking. METHODS: From September 2015 to July 2019, 82 patients with MAC underwent MDCT at two institutions to evaluate for surgical mitral valve replacement (SMVR), transcatheter mitral valve replacement (TMVR), or medical management. Type 1 MAC was defined as <270° annular calcium and Type 2 as ≥270°. Absence/presence of predicted left ventricular outflow tract (LVOT) obstruction with virtual valve placement was used to further define Type 2 MAC into 2A/B for our treatment algorithm. RESULTS: Type 1 MAC was present in 51.2%, Type 2A in 18.3%, and Type 2B in 30.5%. Operable Type 1 patients (50.0%) underwent hybrid transatrial TMVR or SMVR. Type 2A underwent a variety of treatments, and Type 2B surgical candidates (40.0%) underwent hybrid transatrial TMVR secondary to difficult suture anchoring with significant MAC and predicted LVOT obstruction. At a follow-up of 29.6 ± 12.0 months, mortality was 42.7% with 46.3% in the intervention group and 39.0% in the medical group (p = 0.47). All percutaneous TMVR patients expired. This translated to a disproportionate number of Type 2A deaths (80.0% with intervention), but all were high/extreme surgical risk. The hybrid TMVR group consisted of 95.0% Type 1/2B patients and had a lower Society of Thoracic Surgeons predicted risk of operative mortality (7.4% vs. 9.2%, p = 0.43)/mortality. CONCLUSIONS: The highest mortality was seen in percutaneous TMVR Type 2A MAC patients, but they were at the greatest risk. Here we provide an objective MAC treatment algorithm for all-comers based on operability/anatomy.

Implications of hydrodynamic testing to guide sizing of self-expanding transcatheter heart valves for valve-in-valve procedures.

AIMS: The commonly used valve-in-valve (VIV) app recommends sizing based on dimensions of both the transcatheter heart valve (THV) and bioprosthetic surgical valve. The implications of hydrodynamic testing to guide VIV sizing are poorly understood. This bench study assessed the hydrodynamic performance of different sizes of self-expanding supra-annular THVs in three different surgical aortic bioprostheses at different implantation depths. METHODS: A small versus medium ACURATE neo (ACn), and a 26 mm versus 29 mm Evolut R were assessed after VIV implantation in 25 mm Mitroflow, Mosaic, and Magna Ease aortic surgical bioprostheses, at three implantation depths (+2 mm, -2 mm, and -6 mm). RESULTS: The medium-sized ACn had lower gradients compared to the small ACn when the THV was implanted high (+2 mm, or -2 mm). The 29 mm Evolut R had lower gradients compared to a 26 mm Evolut R for all implantation depths, except for a depth of -2 mm in the 25 mm Mitroflow. The medium ACn and 29 mm Evolut R had larger effective orifice areas compared to the small ACn and 26 mm Evolut R, respectively. Both Evolut R sizes had acceptable regurgitant fractions (<15%), while both ACn sizes were above the acceptable performance criteria (>15%), at all implantation depths. CONCLUSIONS: Use of a larger self-expanding THV was associated with superior hydrodynamic performance if the THV was implanted high. Hydrodynamic testing can provide additional information to the VIV app to help guide VIV sizing.

Contemporary suprasternal transcatheter aortic valve replacement: A multicenter experience using a simple, reliable alternative access approach.

OBJECTIVES: To describe outcomes after suprasternal (SS) transcatheter aortic valve replacement (TAVR) as a new alternative access approach. BACKGROUND: There still remains a cohort of the TAVR population who are not suitable for a transfemoral (TF) approach. SS-TAVR is a safe and effective alternative to TF-TAVR and has now become our preferred alternative access route. METHODS: We retrospectively reviewed all patients from New York Presbyterian Hospital, Columbia University Medical Center and Princeton Baptist Medical Center who underwent SS-TAVR from 2015 to July 2018. A total of 84 patients were included in the study. RESULTS: Technical success was achieved in all cases. Thirty-day survival was 98.8% (n = 83). There were minimal complications. Most notably, there were no transient ischemic attacks or strokes (0%, n = 0). Reexploration for bleeding was 3.6% (n = 3), and major bleeding was 1.7% (n = 1). We also achieved satisfactory results with a mean aortic valve gradient of 6.07 ± 3.79 mmHg and an aortic valve area of 2.21 ± 0.51 cm2 . No patients had anything more than mild paravalvular leak. The mean length of stay (LOS) in the intensive care unit was 1.42 ± 1.23 days, and hospital LOS was 4.20 ± 3.29 days. CONCLUSIONS: SS access for TAVR is an extremely important technique to have in any valve team's alternative access armamentarium. This technique can be safely and reliably reproduced with any standard hybrid operating room setup and no additional equipment, and it can be used with any commercially available valve system. In the current experience, minimal complications and excellent early term results were obtained.

Urgent transcatheter aortic valve replacement for severe acute aortic regurgitation following open mitral valve surgery.

Transcatheter aortic valve replacement (TAVR) is not currently approved for pure native valve aortic incompetence, and is typically performed on a compassionate basis in selected patients who are at high risk for conventional surgery. We describe the first use of TAVR to treat iatrogenic severe acute pure aortic incompetence following mitral valve surgery. A 71-year-old gentleman developed life-threatening acute aortic regurgitation (AR) within hours of a very challenging fifth open heart mitral valve replacement. Careful inspection of echocardiographic and computed tomographic imaging identified the cause as a disrupted left coronary cusp at the commissure caused by the surgical mitral annular reconstruction. Medical management with afterload reduction failed with recurrent pulmonary edema, and a sixth open heart surgery was deemed prohibitively high risk. The lack of aortic annular calcium onto which anchors a transcatheter valve was a concern for TAVR. However, we postulated that the struts of the mitral valve bioprosthesis would offer some support to the TAVR valve. We opted for a self-expanding system because of concerns about potential unfavorable interaction between the balloon onto which balloon-expandable bioprosthesis is mounted and the struts of the mitral bioprosthesis, and because the Evolut R system has additional anchoring points at the crown which might enhance transcatheter valve stability in the non-calcified annulus, compared with the Edwards Sapien system. Transfemoral TAVR, performed with a Medtronic Evolut R 34 mm system under general anesthesia and using moderately rapid ventricular pacing, was successful with minimal residual AR. On follow-up 1 month later the patient was asymptomatic, and the aortic and mitral bioprostheses were functioning normally on echocardiogram.

Balloon-expandable transcatheter aortic valve implantation with or without pre-dilation - results of a meta-analysis of 3 multicenter registries.

BACKGROUND: To evaluate the outcomes of transcatheter aortic valve implantation (TAVI) without balloon aortic valvuloplasty (BAV) in a real-world setting through a patient-level meta-analysis. METHODS: The meta-analysis included patients of three European multicenter, prospective, observational registry studies that compared outcomes after Edwards SAPIEN 3 or XT TAVI with (n = 339) or without (n = 355) BAV. Unadjusted and adjusted pooled odds ratios (with 95% confidence intervals) were calculated for procedural and 30-day outcomes. RESULTS: Median procedural time was shorter in the non-BAV group than in the BAV group (73 versus 93 min, p = 0.001), as was median fluoroscopy time (7 versus 11 min, p = 0.001). Post-delivery balloon dilation (15.5% versus 22.4%, p = 0.02) and catecholamine use (9.0% vs. 17.9%; p = 0.016) was required less often in the non-BAV group than in the BAV group with the difference becoming insignificant after multiple adjustment. There was a reduced risk for periprocedural atrioventricular block during the intervention (1.4% versus 4.1%, p = 0.035) which was non-significant after adjustment. The rate of moderate/severe paravalvular regurgitation post-TAVI was 0.6% in the no-BAV group versus 2.7% in the BAV group. There were no between-group differences in the risk of death, stroke or other adverse clinical outcomes at day 30. CONCLUSIONS: This patient-level meta-analysis of real-world data indicates that TAVI performed without BAV is advantageous as it has an adequate device success rate, reduced procedure time and no adverse effects on short-term clinical outcomes.

Incidence, predictors, and clinical outcomes of coronary obstruction following transcatheter aortic valve replacement for degenerative bioprosthetic surgical valves: insights from the VIVID registry.

Aims: There are limited data on coronary obstruction following transcatheter valve-in-valve (ViV) implantation inside failed aortic bioprostheses. The objectives of this study were to determine the incidence, predictors, and clinical outcomes of coronary obstruction in transcatheter ViV procedures. Methods and results: A total of 1612 aortic procedures from the Valve-in-Valve International Data (VIVID) Registry were evaluated. Data were subject to centralized blinded corelab computed tomography (CT) analysis in a subset of patients. The virtual transcatheter valve to coronary ostium distance (VTC) was determined. A total of 37 patients (2.3%) had clinically evident coronary obstruction. Baseline clinical characteristics in the coronary obstruction patients were similar to controls. Coronary obstruction was more common in stented bioprostheses with externally mounted leaflets or stentless bioprostheses than in stented with internally mounted leaflets bioprostheses (6.1% vs. 3.7% vs. 0.8%, respectively; P < 0.001). CT measurements were obtained in 20 (54%) and 90 (5.4%) of patients with and without coronary obstruction, respectively. VTC distance was shorter in coronary obstruction patients in relation to controls (3.24 ± 2.22 vs. 6.30 ± 2.34, respectively; P < 0.001). Using multivariable analysis, the use of a stentless or stented bioprosthesis with externally mounted leaflets [odds ratio (OR): 7.67; 95% confidence interval (CI): 3.14-18.7; P < 0.001] associated with coronary obstruction for the global population. In a second model with CT data, a shorter VTC distance predicted this complication (OR: 0.22 per 1 mm increase; 95% CI: 0.09-0.51; P < 0.001), with an optimal cut-off level of 4 mm (area under the curve: 0.943; P < 0.001). Coronary obstruction was associated with a high 30-day mortality (52.9% vs. 3.9% in the controls, respectively; P < 0.001). Conclusion: Coronary obstruction following aortic ViV procedures is a life-threatening complication that occurred more frequently in patients with prior stentless or stented bioprostheses with externally mounted leaflets and in those with a short VTC.

Modified Single-Puncture Technique for Transcatheter Aortic Valve Implantation in Patients without Peripheral Vascular Access.

Transcatheter aortic valve implantation (TAVI) is now routinely performed to treat inoperable and high-risk patients with severe aortic stenosis (AS). Transapical or transaortic approaches are alternative routes used when peripheral accesses are unsuitable.Correct placement of the device is achieved with the help of an angiography performed with a pigtail catheter to identify the deployment view. However, in patients with severe vascular disease, placement of a pigtail catheter may not be possible.We report a modified single-puncture technique, whereby a single access point is used to perform both angiography and TAVI by using visible calcification landmarks as reference points.

Concomitant transatrial valve-in-valve in pulmonal and tricuspid position.

Transcatheter valve implantation in the pulmonary valve has been established as a valuable treatment option for patients with conduit failure in the right ventricular outflow tract, most often with the use of the Melody valve. Transcatheter valve-in-valve (VIV) implantation in the tricuspid position is restricted to single case reports, most often with the implantation of the Edwards SAPIEN valve. A 67 years old male with carcionoid syndrome and previously implanted bioprosthesis in the pulmonary and tricuspid valve now presented with worsening symptoms due to degeneration of both bioprostheses. The risk of new open surgery was deemed to high. We report of the first transatrial double VIV implantation using the balloon expandable Edwards SAPIEN XT in pulmonary and tricuspid position.

Neo-annulus: a reference plane in a surgical heart valve to facilitate a valve-in-valve procedure.

OBJECTIVES: To determine the level of the narrowest plane (neo-annulus) of a surgical heart valve (SHV), which could be used for sizing and securing a transcatheter heart valve (THV) during a valve-in-valve (VIV) procedure and define its relationship with the fluoroscopic markers of the SHV. BACKGROUND: In the native aortic valve, the aortic annulus is used as a reference plane for sizing and deployment of THV as it provides the narrowest dimension to securely anchor the THV. However, the reference level for different models of SHV that are currently treated by a VIV procedure remains unknown. METHODS: We studied 13 aortic SHVs from all major heart valve manufacturers (labeled size 21, 22, or 23). A 26cc valvuloplasty balloon was inflated with contrast within each SHV under fluoroscopy to achieve a 'waist'. The level of the 'waist' was compared with the SHV and its fluoroscopic markers to identify the level of the neo-annulus. RESULTS: In all SHVs tested, the balloon 'waist' or 'neo-annulus' was at the level of the sewing ring. When the fluoroscopic marker of the SHV was the sewing ring, the level of the neo-annulus was also at that level, irrespective of supra-annular or intra-annular design. However, when the fluoroscopic marker was the stent frame, the relationship between the fluoroscopic marker and the level of the neo-annulus was different for supra-annular and intra-annular designs. This correlation was not possible in two models of SHV as neither the stent nor the sewing ring was radio-opaque. CONCLUSIONS: We have demonstrated that the narrowest portion of all SHVs is at the level of its sewing ring, which can be identified fluoroscopically and should be used as a reference level during a VIV procedure.

Open issues in transcatheter aortic valve implantation. Part 2: procedural issues and outcomes after transcatheter aortic valve implantation.

This article provides an overview on procedure-related issues and uncertainties in outcomes after transcatheter aortic valve implantation (TAVI). The different access sites and how to select them in an individual patient are discussed. Also, the occurrence and potential predictors of aortic regurgitation (AR) after TAVI are addressed. The different methods to quantify AR are reviewed, and it appears that accurate and reproducible quantification is suboptimal. Complications such as prosthesis-patient mismatch and conduction abnormalities (and need for permanent pacemaker) are discussed, as well as cerebrovascular events, which emphasize the development of optimal anti-coagulative strategies. Finally, recent registries have shown the adoption of TAVI in the real world, but longer follow-up studies are needed to evaluate the outcome (but also prosthesis durability). Additionally, future studies are briefly discussed, which will address the use of TAVI in pure AR and lower-risk patients.

Open issues in transcatheter aortic valve implantation. Part 1: patient selection and treatment strategy for transcatheter aortic valve implantation.

An exponential increase in the use of transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis has been witnessed over the recent years. The current article reviews different areas of uncertainty related to patient selection. The use and limitations of risk scores are addressed, followed by an extensive discussion on the value of three-dimensional imaging for prosthesis sizing and the assessment of complex valve anatomy such as degenerated bicuspid valves. The uncertainty about valvular stenosis severity in patients with a mismatch between the transvalvular gradient and the aortic valve area, and how integrated use of echocardiography and computed tomographic imaging may help, is also addressed. Finally, patients referred for TAVI may have concomitant mitral regurgitation and/or coronary artery disease and the management of these patients is discussed.

Delayed migration of Sapien valve following a transcatheter mitral valve-in-valve implantation.

We report two cases of delayed migration of the Sapien XT device after a successful mitral valve-in-valve (VIV) implantation. The procedure was performed through a transapical approach. Echocardiography was used to choose the size of the Sapien XT device. Although the immediate results were satisfactory both the cases presented with severe regurgitation (1 week and 3 months). Investigations revealed atrial migration of the Sapien device in both the cases, which was confirmed at the time of reoperation. We discuss possible mechanisms, which could have resulted in the delayed migration and highlight the difference between VIV procedures in mitral position versus other positions.