Coronary Risk in Transcatheter Aortic Valve Replacement, Overview of Data, Challenges, and Best Practices.

Coronary artery obstruction is a rare complication of transcatheter aortic valve replacement (TAVR). This risk increases in TAVR-valve-in-valve procedure. Several anatomic risk factors were described in many studies to identify the predictive elements of coronary artery occlusion on computed tomography cardiac scan. Rescue percutaneous coronary intervention was the first approach described to treat this complication with a high mortality rate. Later on, preventive chimney stenting technique was evaluated and results showed that is a safe and effective strategy but it leads to a difficult coronary access later. New preventive techniques are being evaluated recently (Basilica and Shorctut).

BASILICA Procedure Prior to Valve-in-Valve TAVR in a Supra-Annular TAV Prosthesis.

An 80-year-old man with a supra-annular transcatheter aortic valve (TAV) prosthesis presented with severe transvalvular aortic regurgitation 18 months after the TAV replacement procedure. The authors report the first ever valve-in-valve procedure using BASILICA (bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction) in such a supra-annular TAV prosthesis. Minimal paravalvular leakage, normal coronary artery flow, and easy coronary access were seen postimplantation. (Level of Difficulty: Advanced.).

Effect of leaflet laceration on transcatheter aortic valve replacement fluid mechanics and comparison with surgical aortic valve replacement.

BACKGROUND: Leaflet thrombosis after surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) may be caused by blood flow stagnation in the native and neosinus regions. To date, aortic leaflet laceration has been used to mitigate coronary obstruction following TAVR; however, its influence on the fluid mechanics of the native and neosinus regions is poorly understood. This in vitro study compared the flow velocities and flow patterns in the setting of SAVR vs TAVR with and without aortic leaflet lacerations. METHODS: Two valves, (23-mm Perimount and 26-mm SAPIEN 3; Edwards Lifesciences) were studied in a validated mock flow loop under physiologic conditions. Neosinus and native sinus fluid mechanics were quantified using particle image velocimetry in the left and noncoronary cusp, with an increasing number of aortic leaflets lacerated or removed. RESULTS: Across all conditions, SAVR had the highest average sinus and neosinus velocities, and this value was used as a reference to compare against the TAVR conditions. With an increasing number of leaflets lacerated or removed with TAVR, the average sinus and neosinus velocities increased from 25% to 70% of SAVR flow (100%). Diastolic velocities were substantially augmented by leaflet laceration. Also, the shorter frame of the SAVR led to higher flow velocities compared with the longer frame of the TAVR, even after complete leaflet removal. CONCLUSIONS: Leaflet laceration augmented TAVR native and neosinus flow fields, approaching that of SAVR. These findings may have potential clinical implications for the use of single or multiple leaflet lacerations to reduce leaflet thrombosis and thus potentially improve TAVR durability.

Coronary Obstruction From TAVR in Native Aortic Stenosis: Development and Validation of Multivariate Prediction Model.

BACKGROUND: Transcatheter aortic valve replacement (TAVR)-related coronary artery obstruction prediction remains unsatisfactory despite high mortality and novel preventive therapies. OBJECTIVES: This study sought to develop a predictive model for TAVR-related coronary obstruction in native aortic stenosis. METHODS: Preprocedure computed tomography and fluoroscopy images of patients in whom TAVR caused coronary artery obstruction were collected. Central laboratories made measurements, which were compared with unobstructed patients from a single-center database. A multivariate model was developed and validated against a 1:1 propensity-matched subselection of the unobstructed cohort. RESULTS: Sixty patients with angiographically confirmed coronary obstruction and 1,381 without obstruction were included. In-hospital death was higher in the obstruction cohort (26.7% vs 0.7%; P < 0.001). Annular area and perimeter, coronary height, sinus width, and sinotubular junction height and width were all significantly smaller in the obstructed cohort. Obstruction was most common on the left side (78.3%) and at the level of the coronary artery ostium (92.1%). Coronary artery height and sinus width, but not annulus area, were significant risk factors for obstruction by logistic regression but performed poorly in predicting obstruction. The new multivariate model (coronary obstruction IF cusp height > coronary height, AND virtual valve-to-coronary distance ≤4 mm OR culprit leaflet calcium volume >600 mm3) performed well, with an area under the curve of 0.93 (sensitivity = 0.93, specificity = 0.84) for the left coronary artery and 0.94 (sensitivity = 0.92, specificity = 0.96) for the right. CONCLUSIONS: A novel computed tomography-based multivariate prediction model that can be implemented routinely in real-world practice predicted coronary artery obstruction from TAVR in native aortic stenosis.

Leaflet modification or chimney stenting in patients at risk for coronary artery obstruction in valve-in-valve procedure for a failed surgical bioprosthetic aortic valve.

Valve-in-valve transcatheter aortic valve replacement (VIV-TAVR) for a degenerated surgical aortic bioprosthesis is a well-established treatment modality but carries an increased risk of coronary artery obstruction (CAO) with potentially catastrophic consequences. Both chimney stenting and leaflet modification by BASILICA (Bioprosthetic or Native Aortic Scallop Intentional Laceration to Prevent Iatrogenic Coronary Obstruction) are increasingly employed and can be highly effective means of preventing CAO. Using a case report, in which both strategies were utilized, as a platform for detailed discussion, we address the indications, contraindications, and relative merits of each technique in the prevention of CAO.

Feasibility of precise commissural and coronary alignment with balloon-expandable TAVI.

INTRODUCTION AND OBJECTIVES: We aimed to describe the feasibility and preliminary outcomes of commissural alignment (CA) for the balloon-expandable transcatheter heart valve. METHODS: The relationship among native commissures and transcatheter aortic valve implantation neocommissures was analyzed in 10 consecutive patients with tricuspid severe aortic stenosis undergoing transcatheter aortic valve implantation after guided implantation based on computed tomography analysis with a self-developed software. CA was predicted by in silico bio-modelling in the 10 patients and the calculated rotation was applied during crimping. Degrees of CA and coronary overlap (CO) were measured through 1-month follow up computed tomography. Transvalvular residual gradients and the rate of paravalvular leak were also analyzed. RESULTS: Mean commissural misalignment was 16.7±8°. Four patients showed mild misalignment but none of them showed a moderate or severe degree of misalignment. The in silico model accurately predicted the final in vivo position with a correlation coefficient of 0.983 (95%CI, 0.966-0.992), P <.001. Severe CO with right coronary ostium occurred in 3 patients likely due to ostial eccentricity, and CO was not present with the left coronary artery in any of the patients. Mean transaortic gradient was 6.1±3.3mmHg and there were no moderate-severe paravalvular leaks. CONCLUSIONS: Patient-specific rotation during valve crimping based on preprocedural computed tomography is feasible with balloon-expandable devices and is associated with the absence of moderate or severe commissural misalignment and left main CO.

Aortic Annulus S-Curve: Implications for Transcatheter Aortic Valve Replacement and Related Procedures, Part 1.

Most transcatheter aortic valve replacement-related procedures (eg, transcatheter aortic valve replacement implantation depth, commissural alignment, coronary access, bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction, paravalvular leak closure) require an optimal fluoroscopic viewing angle located somewhere along the aortic annulus S-curve. Chamber views, coronary cusp and coronary anatomy, can be understood along the aortic annulus S-curve. A better understanding of the optimal fluoroscopic viewing angles along the S-curve may translate into increased operator confidence and improved safety and efficacy while reducing procedural time, radiation dose, contrast volume, and complication rates.

Leaflet-splitting device to prevent coronary artery obstruction in valve-in-valve transcatheter aortic valve implantation.

Coronary artery obstruction is a life-threatening complication of transcatheter aortic valve replacement procedures, and current preventive strategies are suboptimal. The novel ShortCut device splits bioprosthetic valve leaflets that are at risk of causing coronary artery obstruction after transcatheter aortic valve implantation, allowing for normal coronary flow. In this video tutorial, we demonstrate a valve-in-valve transcatheter aortic valve implantation using a dedicated leaflet-splitting device for prevention of coronary artery obstruction in transcatheter aortic valve replacement.

Transposition of basilic vein for vascular access for haemodialysis: An experience of a tertiary care hospital.

Basilic vein transposition (BVT) is the preferred permanent haemodialysis access due to better patency and lower infection rates compared to synthetic grafts. The outcomes of BVT cases, performed at Shifa International Hospital, Islamabad, from March 2006 to June 2018, were ambispectively investigated. The primary patency of the fistula was assessed immediately after surgery, at 24 hours, at 7-14 days, at 6-8 weeks and then at 3-6 months. A total of 160 patients were included in the study, out of which 83 (51.87%) were males while 77 (48.12%) were females. Of the total 160 patients, 119 (74.4%) underwent one stage BVT, while 41 (25.6%) underwent two stage BVT. One hundred and thirty-five (84.4%) procedures were successful and survived while in 25 (15.6%) cases it failed. Mean basilic vein diameter was 2.712±0.772 mm. Overall, 10(6.3%) patients had bleeding, 15(9.4%) fistulae thrombosed, 6(3.8%) had steal syndrome and only 1 (0.6%) patient developed pseudo aneurysm. We conclude that BVT is a feasible technique with very good patency rate especially for those patients who have multiple forearm AVF surgeries.

Use of Electrosurgery in Interventional Cardiology.

Transcatheter electrosurgery is a versatile tool that can be used to cut cardiac tissue without the need for a sternotomy, cardiopulmonary bypass, and cardioplegia. With adequate imaging and suitable anatomy, any cardiac tissue can be cut. Thus, transcatheter electrosurgery can provide bespoke therapies for complex patients who often have no other good treatment options. In this review, we will discuss the common applications for electrosurgical tissue traversal and laceration, including transcaval access, BASILICA, LAMPOON, and ELASTA-Clip, summarizing the evidence and the key technical steps for each.

Risk of Coronary Obstruction During Redo-TAVR in Patients With Bicuspid Versus Tricuspid Aortic Valve Stenosis.

OBJECTIVES: The aim of this study was to investigate the risk of coronary obstruction during redo-transcatheter aortic valve replacement (TAVR) within a previously implanted self-expanding valve in bicuspid aortic valve (BAV) versus tricuspid aortic valve (TAV) stenosis. BACKGROUND: The prevalence of BAV in TAVR patients is expected to increase as the indication expands; however, no study has investigated the risk of coronary obstruction for future redo-TAVR in these patients. METHODS: Computed tomography (CT) simulation analysis was performed in 86 type 0 BAV, 70 type 1 BAV, and 132 TAV patients who underwent TAVR with 1 VenusA-Valve (Venus Medtech) between January 2014 and December 2019. RESULTS: CT-identified risk of coronary obstruction during redo-TAVR was observed in 36.1% of patients for the left coronary ostium (LCO) and 27.8% of patients for the right coronary ostium (RCO); however, the incidences were significantly lower in the type 0 BAV group than in the type 1 BAV or TAV group (for LCO: OR: 1.00 [reference] vs OR: 2.49; 95% CI: 1.24-5.01 vs OR: 2.60; 95% CI: 1.40-4.81; for RCO: OR: 1.00 [reference] vs OR: 2.14; 95% CI: 1.02-4.48 vs OR: 1.97; 95% CI: 1.02-3.80). The leaflet laceration technique may be unfeasible to improve coronary flow in 61.5% of the threatened LCOs and 58.8% of the threatened RCOs during redo-TAVR. The percentages were significantly or numerically lower in the type 0 BAV group than other groups (for LCO: 26.3% vs 62.1% vs 73.2%; P overall = 0.001; for RCO: 43.8% vs 65.2% vs 61.0%; P overall = 0.374). CONCLUSIONS: Differences in anatomical features may impact the feasibility of future redo-TAVR. Type 0 BAV anatomy was associated with the lower incidence of CT-identified risk of coronary obstruction during redo-TAVR, and the leaflet laceration technique may be more feasible to ensure coronary flow in this population.

Fístula arteriovenosa con elevación de la vena basílica. Reporte de casos / Arteriovenous fistula with basilic vein elevation. Case series

RESUMEN Las fístulas arteriovenosas (FAV) se requieren para hemodiálisis permanente. Las recomendaciones de acceso preferidas son radio cefálica, braquiocefálica, braquio-basilica con elevación o transposición y tunelización. El objetivo de este trabajo fue presentar la experiencia con la creación de FAV con vena basílica elevada. Entre junio 2017 y marzo 2020, se realizaron trece FAV braquio-basílicas con técnica de elevación de acuerdo al registro de cirugías realizadas por la Unidad, siete hombres y seis mujeres. La edad media fue 65,7 años. En el post operatorio temprano hubo hematomas de antebrazo en dos casos, infección de herida en dos casos, así como un caso de edema. En el periodo de seguimiento, tres no maduraron, y tres pacientes fallecieron; mientras que las FAV restantes aún están funcionando. En conclusión, la FAV braquio-basilica con vena elevada es una alternativa en pacientes que ya han agotado otras opciones.

ABSTRACT Arteriovenous fistula (AVF) is necessary for hemodialysis access. The preferred configurations are radial-cephalic, brachial-cephalic, and brachial-basilic with elevation or transposition and tunneling. The purpose of this study was to present our experience for creating arteriovenous fistulae using the elevation of the basilic vein technique. Between June 2017 and March 2020, thirteen brachial-basilic fistulae with elevation of the basilic vein were performed in seven male and six female subjects. Their mean age was 65.7 years. During the early post-op period, there were two cases of forearm hematoma, wound infection in two cases, and edema in one case. During the follow-up period, three fistulae did not have a good progression, and three patients died; the remaining AVFs are still working. In conclusion, brachial-basilic AVF with elevation of the basilic vein is an alternative in patients who have already exhausted other access options.

Risk Assessment of Coronary Obstruction During Transcatheter Aortic Valve Replacement: Insights From Post-BASILICA Computed Tomography.

OBJECTIVES: The aim of this study was to examine the predictive value of preprocedural computed tomography (CT)-based risk stratification of coronary obstruction during transcatheter aortic valve replacement (TAVR) on the basis of geometric measurements on postprocedural CT. BACKGROUND: Proper patient selection for additional procedures to prevent coronary obstruction during TAVR has not been adequately evaluated. METHODS: Pre- and postprocedural computed tomographic scans of 28 patients treated using bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction (BASILICA) and TAVR were analyzed. Using the postprocedural computed tomographic images, threatened coronary obstruction (TCO) was defined as: 1) ostial obstruction (adherence of the transcatheter heart valve [THV] to the coronary ostium with leaflet extension above the ostium); and/or 2) sinus sequestration (THV adherence to the sinotubular junction [STJ] with leaflet extension above the STJ) and was substratified into complete and incomplete types. RESULTS: A total of 51 leaflets were evaluated (88% surgical tissue valves) after excluding leaflets not visible on CT (n = 5). On postprocedural CT, complete TCO was observed in 25.4% (13 of 51 leaflets). On preprocedural CT, leaflets were at high risk for complete TCO (incidence 53%) if the virtual THV-to-coronary distance (VTC) was <3.0 mm, or if the virtual THV-to-STJ distance (VTSTJ) was <1.0 mm with STJ height - leaflet length <0 mm (leaflet-STJ mismatch). Leaflets were at low risk (incidence 0%) if the VTC was ≥3 mm and VTSTJ was ≥3.0 mm or STJ height - leaflet length was ≥+2.0 mm. Of 28 leaflets treated using BASILICA, complete TCO was seen in 35.7% (n = 10), due to sinus sequestration (100%) with coexisting ostial obstruction (30%). Actual coronary events occurred in 7.1% (n = 2) because of leaflet prolapse, corresponding to an absolute risk reduction by BASILICA of 29% (P = 0.021). CONCLUSIONS: Risk assessment of coronary obstruction after TAVR may improve with a multiparametric approach incorporating VTC, VTSTJ, and leaflet-STJ mismatch. BASILICA appeared to reduce actual coronary events even in leaflets with anticipated coronary obstruction.