BI-SILICA During Transcatheter Aortic Valve Replacement for Noncalcific Aortic Insufficiency: Initial Human Experience

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.

Sealing Behavior in Transcatheter Bicuspid and Tricuspid Aortic Valves Replacement Through Patient-Specific Computational Modeling

Background: Patient-specific computer simulation of transcatheter aortic valve replacement (TAVR) can provide unique insights in device-patient interaction. Aims: This study was to compare transcatheter aortic valve sealing behavior in patients with bicuspid aortic valves (BAV) and tricuspid aortic valves (TAV) through patient-specific computational modeling. Methods: Patient-specific computer simulation was retrospectively performed with FEops HEARTguide for TAVR patients. Simulation output was compared with postprocedural computed tomography and echocardiography to validate the accuracy. Skirt malapposition was defined by a distance larger than 1 mm based on the predicted device-patient interaction by quantifying the distance between the transcatheter heart valve (THV) skirt and the surrounding anatomical regions. Results: In total, 43 patients were included in the study. Predicted and observed THV frame deformation showed good correlation (R 2 ≥ 0.90) for all analyzed measurements (maximum diameter, minimum diameter, area, and perimeter). The amount of predicted THV skirt malapposition was strongly linked with the echocardiographic grading of paravalvular leakage (PVL). More THV skirt malapposition was observed for BAV cases when compared to TAV cases (22.7 vs. 15.5%, p < 0.05). A detailed analysis of skirt malapposition showed a higher degree of malapposition in the interleaflet triangles section for BAV cases as compared to TAV patients (11.1 vs. 5.8%, p < 0.05). Conclusions: Patient-specific computer simulation of TAVR can accurately predict the behavior of the Venus A-valve. BAV patients are associated with more malapposition of the THV skirt as compared to TAV patients, and this is mainly driven by more malapposition in the interleaflet triangle region.

Prevention of coronary obstruction in patients at risk undergoing transcatheter aortic valve implantation: the Hamburg BASILICA experience

OBJECTIVES

This study aimed to assess the clinical outcome of the bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary obstruction (BASILICA) technique in a single-center patient cohort considered at high or prohibitive risk of transcatheter aortic valve implantation (TAVI)-induced coronary obstruction.

METHODS

Between October 2019 and January 2021, a total of 15 consecutive patients (age 81.0 [78.1, 84.4] years; 53.3% female; EuroSCORE II 10.6 [6.3, 14.8] %) underwent BASILICA procedure prior to TAVI at our institution. Indications for TAVI were degeneration of stented (n = 12, 80.0%) or stentless (n = 1, 6.7%) bioprosthetic aortic valves, or calcific stenosis of native aortic valves (n = 2, 13.3%), respectively. Individual risk of TAVI-induced coronary obstruction was assessed by pre-procedural computed tomography analysis. Procedural and 30-day outcomes were documented in accordance with Valve Academic Research Consortium (VARC)-2 criteria.

RESULTS

BASILICA was attempted for single left coronary cusp in 12 patients (80.0%), for single right coronary cusp in 2 patients (13.3%), and for both cusps in 1 patient (6.7%), respectively. The procedure was feasible in 13 patients (86.7%) resulting in effective prevention of coronary obstruction, whilst TAVI was performed without prior successful bioprosthetic leaflet laceration in two patients (13.3%). In one of these patients (6.7%), additional chimney stenting immediately after TAVI was performed. No all-cause deaths or strokes were documented after 30 days.

CONCLUSION

The BASILICA technique appears to be a feasible, safe and effective concept to avoid iatrogenic coronary artery obstruction during TAVI in both native and bioprosthetic valves of patients at high or prohibitive risk. ClinicalTrials.gov Identifier: NCT04227002 (Hamburg AoRtic Valve cOhoRt).

Transcatheter Aortic Valve Replacement in Bicuspid Aortic Valve Stenosis

After 15 years of successive randomized, controlled trials, indications for transcatheter aortic valve replacement (TAVR) are rapidly expanding. In the coming years, this procedure could become the first line treatment for patients with a symptomatic severe aortic stenosis and a tricuspid aortic valve anatomy. However, randomized, controlled trials have excluded bicuspid aortic valve (BAV), which is the most frequent congenital heart disease occurring in 1% to 2% of the total population and representing at least 25% of patients 80 years of age or older referred for aortic valve replacement. The use of a less invasive transcatheter therapy in this elderly population became rapidly attractive, and approximately 10% of patients currently undergoing TAVR have a BAV. The U.S. Food and Drug Administration and the "European Conformity" have approved TAVR for low-risk patients regardless of the aortic valve anatomy whereas international guidelines recommend surgical replacement in BAV populations. Given this progressive expansion of TAVR toward younger and lower-risk patients, heart teams are encountering BAV patients more frequently, while the ability of this therapy to treat such a challenging anatomy remains uncertain. This review will address the singularity of BAV anatomy and associated technical challenges for the TAVR procedure. We will examine and summarize available clinical evidence and highlight critical knowledge gaps regarding TAVR utilization in BAV patients. We will provide a comprehensive overview of the role of computed tomography scans in the diagnosis, and classification of BAV and TAVR procedure planning. Overall, we will offer an integrated framework for understanding the current role of TAVR in the treatment of bicuspid aortic stenosis and for guiding physicians in clinical decision-making.

Preventing Coronary Obstruction During Transcatheter Aortic Valve Replacement: From Computed Tomography to BASILICA

Coronary artery obstruction is an uncommon but devastating complication of transcatheter aortic valve replacement (TAVR). Computed tomography appears to be a sensitive but nonspecific predictor of coronary artery obstruction. Transcatheter approaches to prevent and treat coronary artery obstruction, such as "snorkel" stenting, are unsatisfactory because of serious early and late ischemic complications. Bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction during TAVR (BASILICA) is an early-stage transcatheter procedure to prevent coronary artery obstruction. It works by splitting the native or bioprosthetic leaflets so that they splay after TAVR and preserve coronary artery inflow. Because of the paucity of suitable alternatives, there is interest in the BASILICA technique despite its infancy. This tutorial review summarizes current thinking about how to predict and prevent coronary artery obstruction using BASILICA. First, the authors depict the main pathophysiological mechanisms of TAVR-associated coronary artery obstruction, along with the factors thought to contribute to coronary obstruction. Next, the authors provide a step-by-step guide to analyzing pre-procedural computed tomographic findings to assess obstruction risk and, if desirable, to plan BASILICA. Next, the authors describe the mechanisms underlying transcatheter electrosurgery. Finally, they provide step-by-step guidance on how to perform the procedure, along with a required equipment list.

The bicuspid aortic valve: Still a toothy problem

Transcatheter aortic valve replacement (TAVR) is an acceptable treatment alternative to surgical aortic valve replacement in selected patients with a bicuspid aortic valve. TAVR appears to have acceptable mid-term outcomes in patients with bicuspid aortic stenosis. A large-scale, randomized, clinical trial is necessary to better define the role of TAVR for patients with bicuspid aortic stenosis.

The BASILICA Trial: Prospective Multicenter Investigation of Intentional Leaflet Laceration to Prevent TAVR Coronary Obstruction

OBJECTIVES

The BASILICA (Bioprosthetic or native Aortic Scallop Intentional Laceration to prevent Iatrogenic Coronary Artery obstruction during TAVR) investigational device exemption trial was a prospective, multicenter, single-arm safety and feasibility study.

BACKGROUND

Coronary artery obstruction is a rare but devastating complication of transcatheter aortic valve replacement (TAVR). Current stent-based preventative strategies are suboptimal. Bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction during TAVR (BASILICA) is a novel transcatheter technique performed immediately before TAVR to prevent coronary artery obstruction.

METHODS

Subjects with severe native or bioprosthetic aortic valve disease at high or extreme risk for surgery, and at high risk of coronary artery obstruction, were included. The primary success endpoint was successful BASILICA and TAVR without coronary obstruction or reintervention. The primary safety endpoint was freedom from major adverse cardiovascular events. Data were independently monitored. Endpoints were independently adjudicated. A core laboratory analyzed computed tomography images.

RESULTS

Between February 2018 and July 2018, 30 subjects were enrolled. Primary success was met in 28 (93%) subjects. BASILICA traversal and laceration was successful in 35 of 37 (95%) attempted leaflets. There was 100% freedom from coronary obstruction and reintervention. Primary safety was met in 21 (70%), driven by 6 (20%) major vascular complications related to TAVR but not BASILICA. There was 1 death at 30 days. There was 1 (3%) disabling stroke and 2 (7%) nondisabling strokes. Transient hemodynamic compromise was rare (7%) and resolved promptly with TAVR.

CONCLUSIONS

BASILICA was feasible in both native and bioprosthetic valves. Hemodynamic compromise was uncommon. Safety was acceptable and needs confirmation in larger studies. BASILICA appears effective in preventing coronary artery obstruction from TAVR in subjects at high risk.