Transcatheter Aortic Valve Replacement and Coronary Protection Guided by Deep Learning and 3-Dimensional Printing

OBJECTIVE

In this case report, the auxiliary role of deep learning and 3-dimensional printing technology in the perioperative period was discussed to guide transcatheter aortic valve replacement and coronary stent implantation simultaneously.

CASE PRESENTATION

A 68-year-old man had shortness of breath and chest tightness, accompanied by paroxysmal nocturnal dyspnea, 2 weeks before presenting at our hospital. Echocardiography results obtained in the outpatient department showed severe aortic stenosis combined with regurgitation and pleural effusion. The patient was first treated with closed thoracic drainage. After 800 mL of pleural effusion was collected, the patient's symptoms were relieved and he was admitted to the hospital. Preoperative transthoracic echocardiography showed severe bicuspid aortic valve stenosis combined with calcification and aortic regurgitation (mean pressure gradient, 42 mmHg). Preoperative computed tomography results showed a type I bicuspid aortic valve with severe eccentric calcification. The leaflet could be seen from the left coronary artery plane, which indicated an extremely high possibility of coronary obstruction. After preoperative imaging assessment, deep learning and 3-dimensional printing technology were used for evaluation and simulation. Guided transcatheter aortic valve replacement and a coronary stent implant were completed successfully. Postoperative digital subtraction angiography showed that the bioprosthesis and the chimney coronary stent were in ideal positions. Transesophageal echocardiography showed normal morphology without paravalvular regurgitation.

CONCLUSION

The perioperative guidance of deep learning and 3-dimensional printing are of great help for surgical strategy formulation in patients with severe bicuspid aortic valve stenosis with calcification and high-risk coronary obstruction.

Transcatheter Aortic Valve Replacement for Failed Surgical or Transcatheter Bioprosthetic Valves: A Comprehensive Review

Transcatheter aortic valve replacement (TAVR) has proven to be a safe, effective, and less invasive approach to aortic valve replacement in patients with aortic stenosis. In patients who underwent prior aortic valve replacement, transcatheter and surgical bioprosthetic valve dysfunction may occur as a result of structural deterioration or nonstructural causes such as prosthesis-patient mismatch (PPM) and paravalvular regurgitation. Valve-in-Valve (ViV) TAVR is a procedure that is being increasingly utilized for the replacement of failed transcatheter or surgical bioprosthetic aortic valves. Data regarding long-term outcomes are limited due to the recency of the procedure's approval, but available data regarding the short- and long-term outcomes of ViV TAVR are promising. Studies have shown a reduction in perioperative and 30-day mortality with ViV TAVR procedures compared to redo surgical repair of failed bioprosthetic aortic valves, but 1-year and 5-year mortality rates are more controversial and lack sufficient data. Despite the reduction in 30-day mortality, PPM and rates of coronary obstruction are higher in ViV TAVR as compared to both redo surgical valve repair and native TAVR procedures. New transcatheter heart valve designs and new procedural techniques have been developed to reduce the risk of PPM and coronary obstruction. Newer generation valves, new procedural techniques, and increased operator experience with ViV TAVR may improve patient outcomes; however, further studies are needed to better understand the safety, efficacy, and durability of ViV TAVR.

Clinical considerations and challenges in TAV-in-TAV procedures

Transcatheter aortic valve replacement (TAVR) has emerged as a viable treatment for aortic valve disease, including low-risk patients. However, as TAVR usage increases, concerns about long-term durability and the potential for addition interventions have arisen. Transcatheter aortic valve (TAV)-in-TAV procedures have shown promise in selected patients in numerous registries, offering a less morbid alternative to TAVR explantation. In this review, the authors aimed to comprehensively review the experience surrounding TAV-in-TAV, summarize available data, discuss pre-procedural planning, highlight associated challenges, emphasize the importance of coronary obstruction assessment and provide insights into the future of this technique.

A Case of CABG in a Patient with High Risk of Coronary Obstruction during TAV-in-TAV

A 94-year-old man who underwent transcatheter aortic valve (TAV) replacement 6 years ago was admitted because of exertional dyspnea. Transthoracic echocardiography revealed severe aortic regurgitation owing to TAV dysfunction. The patient was considered to have a high risk of occlusion of the sinus of Valsalva during TAV-in-TAV. Therefore, we performed TAV-in-TAV concomitant with coronary artery bypass grafting (CABG). The postoperative course was uneventful, and computed tomography 9 months later revealed patency of both the grafts. Concomitant CABG could be considered as one of the options in patients with a high risk of coronary occlusion during TAV-in-TAV.

Risk of Sinus Sequestration During Redo Transcatheter Aortic Valve Implantation: The Prevalence, Predictors, and Risk Stratification

The number of patients who underwent transcatheter aortic valve implantation (TAVI) with the potential for reintervention is steadily increasing; however, there is a risk of sinus sequestration (SS) during a redo TAVI. The prevalence, predictors, and risk stratification of the risk for SS remain uncertain. We analyzed computed tomography acquired from 263 patients who underwent TAVI between 2021 and 2022: balloon-expandable valve (BEV) (71%) and self-expandable valve (SEV) (29%). Patients were considered at risk for SS if they met the following: (1) BEV frame > sinotubular junction (STJ) or SEV neocommissure greater than the STJ and (2) valve-to-STJ <2 mm. The risk of left, right, and any SS in 51%, 50%, and 65%, respectively, did not differ between BEV and SEV. The predictors of any SS were the height of the left and right coronary cusp (odds ratio [OR] 0.81 and 0.71, cutoff 18.6 and 19.2 mm, respectively) and STJ minus the annulus diameter (OR 0.65, cutoff 3.7 mm) in BEV, and STJ diameter (OR 0.47, cutoff 27.6 mm) in SEV. The number of predictors stratified the risk of any SS: low risk with BEV at 0 predictors (14% at risk of SS), intermediate risk at 1 predictor (65%), high risk at 2 or 3 predictors (81% and 95%), and low risk with SEV at 0 predictors (33%) versus high risk at 1 predictor (91%). In conclusion, 2/3 of patients who underwent TAVI were at risk of SS. The height of the coronary cusp and the STJ diameter were associated with and adequately stratified the risk of SS.

Transcatheter aortic valve implantation in patients with anomalous origin of a coronary artery

Transcatheter aortic valve implantation (TAVI) has become a well-established treatment option for elderly patients with symptomatic severe aortic stenosis. Coronary artery anomalies are an infrequent finding and there have only been few anecdotal reports of patients with coronary anomalies treated with TAVI. We here present a comprehensive overview of existing reports in addition to an own case series to facilitate better understanding of this potentially challenging clinical scenario.

Very Late Sinus of Valsalva Sequestration After Transcatheter Aortic Valve Implantation in Native Aortic Annuli

Coronary artery obstruction caused by sinus sequestration is well described after transcatheter aortic valve implantation in failed bioprosthetic valves, which usually occurs during or shortly after the transcatheter aortic valve implantation procedure. We report the presentation, management, and outcomes of 2 cases of very late sinus sequestration in native aortic annuli, which has not been described before to our knowledge. (Level of Difficulty: Advanced.).

Predicted vs Observed Valve to Coronary Distance in Valve-in-Valve TAVR: A Computed Tomography Study

BACKGROUND

Preprocedural computed tomography (CT) workup with assessment of virtual transcatheter heart valve-to-coronary ostia (VTC) distance and transcatheter heart valve-to-sinus (VTS) distances is recommended to assess the risk of coronary obstruction following valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR).

OBJECTIVES

The authors sought to investigate the agreement of predicted VTC and VTS distances and observed post-TAVR anatomy on CT and their relationship with transcatheter heart valve (THV) expansion and deployment conditions.

METHODS

Fifty-one patients who underwent a balloon-expandable ViV procedure were included in this study. The expansion of the THV stent frame was evaluated at 4 levels: THV inflow, surgical heart valve (SHV) sewing ring, SHV outflow, and THV outflow. Assessment of the VTC/VTS distances was performed on the pre-TAVR CT, and THV-to-coronary ostia and THV-to-sinus distances were assessed on the post-TAVR CT.

RESULTS

Following the ViV procedure, the THV stent frame flared toward the outflow but was generally underexpanded at all levels, particularly at the SHV sewing ring level. Postdilatation impacted the extent of THV expansion, resulting in greater expansion than nominal balloon filling at all 4 THV levels (P < 0.001). Observed THV-to-coronary ostia distances were systematically larger than predicted by the VTC distance (mean difference 1.25 ±1.28 mm) in patients with nominal balloon filling but systematically smaller in case of postdilatation (mean difference -0.45 ± 0.52 mm). A similar relationship was observed between VTS and THV-to-sinus distance measurements.

CONCLUSIONS

With nominal balloon filling, VTC and VTS distances underestimate postprocedural distances due to THV frame underexpansion. However, postdilatation may lead to distances smaller than predicted due to THV overexpansion at the outflow level.

Redo-TAVR: Essential Concepts, Updated Data and Current Gaps in Evidence

Within the last two decades, transcatheter aortic valve replacement (TAVR) has transformed the treatment strategy for symptomatic severe aortic stenosis (AS), representing a less invasive alternative to traditional open-chest surgery. With time, advances in device features, imaging planning, and implantation techniques have contributed to an improvement in safety as well as a reduction in procedural complications. This has led to the expansion of TAVR to lower-risk patients, where TAVR has shown favorable outcomes compared to surgical aortic valve replacement (SAVR). As TAVR expands to younger and lower-risk patients with longer life expectancies, the need for reintervention for failing transcatheter heart valves is expected to increase. Redo-TAVR has gained increasing relevance in the lifetime management of AS as one of the treatment strategies available for structural valve dysfunction (SVD). However, some issues are associated with this approach, including coronary re-access and the risk of coronary obstruction. In this review, we provide essential concepts to properly select candidates for Redo-TAVR, updated data on clinical outcomes and complication rates, and current gaps in evidence.

Coronary Obstruction After Transcatheter Aortic Valve Replacement: Insights From the Spanish TAVI Registry

BACKGROUND

Coronary obstruction (CO) following transcatheter aortic valve replacement (TAVR) is a life-threatening complication, scarcely studied.

OBJECTIVES

The authors analyzed the incidence of CO after TAVR, presentation, management, and in-hospital and 1-year clinical outcomes in a large series of patients undergoing TAVR.

METHODS

Patients from the Spanish TAVI (Transcatheter Aortic Valve Implantation) registry who presented with CO in the procedure, during hospitalization or at follow-up were included. Computed tomography (CT) risk factors were assessed. In-hospital, 30-day, and 1-year all-cause mortality rates were analyzed and compared with patients without CO using logistic regression models in the overall cohort and in a propensity score-matched cohort.

RESULTS

Of 13,675 patients undergoing TAVR, 115 (0.80%) presented with a CO, mainly during the procedure (83.5%). The incidence of CO was stable throughout the study period (2009-2021), with a median annual rate of 0.8% (range 0.3%-1.3%). Preimplantation CT scans were available in 105 patients (91.3%). A combination of at least 2 CT-based risk factors was less frequent in native than in valve-in-valve patients (31.7% vs 78.3%; P < 0.01). Percutaneous coronary intervention was the treatment of choice in 100 patients (86.9%), with a technical success of 78.0%. In-hospital, 30-day, and 1-year mortality rates were higher in CO patients than in those without CO (37.4% vs 4.1%, 38.3% vs 4.3%, and 39.1% vs 9.1%, respectively; P < 0.001).

CONCLUSIONS

In this large, nationwide TAVR registry, CO was a rare, but often fatal, complication that did not decrease over time. The lack of identifiable predisposing factors in a subset of patients and the frequently challenging treatment when established may partly explain these findings.

Coronary Obstruction during Valve-in-Valve Transcatheter Aortic Valve Replacement: Pre-Procedural Risk Evaluation, Intra-Procedural Monitoring, and Follow-Up

Valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) is emerging as an effective treatment for patients with symptomatically failing bioprosthetic valves and a high prohibitive surgical risk; a longer life expectancy has led to a higher demand for these valve reinterventions due to the increased possibilities of outliving the bioprosthetic valve's durability. Coronary obstruction is the most feared complication of valve-in-valve (ViV) TAVR; it is a rare but life-threatening complication and occurs most frequently at the left coronary artery ostium. Accurate pre-procedural planning, mainly based on cardiac computed tomography, is crucial to determining the feasibility of a ViV TAVR and to assessing the anticipated risk of a coronary obstruction and the eventual need for coronary protection measures. Intraprocedurally, the aortic root and a selective coronary angiography are useful for evaluating the anatomic relationship between the aortic valve and coronary ostia; transesophageal echocardiographic real-time monitoring of the coronary flow with a color Doppler and pulsed-wave Doppler is a valuable tool that allows for a determination of real-time coronary patency and the detection of asymptomatic coronary obstructions. Because of the risk of developing a delayed coronary obstruction, the close postprocedural monitoring of patients at a high risk of developing coronary obstructions is advisable. CT simulations of ViV TAVR, 3D printing models, and fusion imaging represent the future directions that may help provide a personalized lifetime strategy and tailored approach for each patient, potentially minimizing complications and improving outcomes.

Hemodynamic and Mid-Term Outcomes for Transcatheter Aortic Valve Replacement in Degenerated Internally Stented Valves

BACKGROUND

Valve-in-valve (ViV) transcatheter aortic valve replacement is indicated in patients undergoing repeat intervention for degenerative aortic valve bioprostheses. Patients with internally stented valves (ie, Mitroflow and Trifecta) are at high risk for coronary artery obstruction during ViV procedures because of valve design, as the leaflets are mounted outside the valve stent.

OBJECTIVES

The aim of this study was to compare the hemodynamic and clinical outcomes of transcatheter aortic valve replacement within internally stented valves (ViV-IS) vs other surgical valves (ViV-OS).

METHODS

Baseline characteristics, hemodynamic parameters, and clinical outcomes of patients who underwent ViV-IS were retrospectively collected and compared with those of patients who underwent ViV-OS.

RESULTS

A total of 250 patients (65% men, median Society of Thoracic Surgeons score 4.4% [IQR: 2.2%-8.4%]) were included. Seventy-one patients (28%) underwent ViV-IS, and 179 (72%) patients underwent ViV-OS. Patients who underwent ViV-OS had better periprocedural hemodynamic status compared with those who underwent ViV-IS (median mean gradient 6 [IQR: 2-13] vs 12 [IQR: 6-16]; P < 0.001). This was not significantly different when both groups were matched on the basis of age, sex, and valve internal diameter size (median mean gradient: 18 [IQR: 13-25] for ViV-OS vs 18 [IQR: 11-24] for ViV-IS; P = 0.36). Coronary protection for potential occlusion was performed more in ViV-IS vs ViV-OS pr (79% vs 6%, respectively; P < 0.001). Patients who underwent ViV-IS had a higher risk for coronary occlusion, requiring stent deployment, compared with those who underwent ViV-OS (54% vs 3%, respectively; P < 0.001. There was no difference in mortality at 3 years between the 2 groups (P = 0.59).

CONCLUSIONS

Patients who underwent ViV-IS had a very high incidence of coronary compromise that can be safely and effectively treated. In the setting of a systematic coronary protection strategy, ViV-OS and ViV-IS provide similar mid-term outcome, and periprocedural hemodynamic status (following adjustment for age, sex, and true internal diameter).

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.

Novel Humanized Biosimulator to Predict Coronary Obstruction in High-Risk Valve-in-Valve Procedures

We developed humanized biosimulator to predict the risk of coronary obstruction among high-risk patients undergoing valve-in-valve (ViV) procedures. In this case, based on unchanged instantaneous wave-free ratio values measured during a ViV simulation session, the procedure was performed safely in the patient the day afterward, without coronary artery issues and with good hemodynamic results. (Level of Difficulty: Advanced.).

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.

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.

Commissural Versus Coronary Optimized Alignment During Transcatheter Aortic Valve Replacement

OBJECTIVES

The aims of this study were to determine the rate of noncentered coronary ostia and their risk for coronary overlap (CO) and to develop an improved orientation strategy for transcatheter aortic valve replacement (TAVR) devices taking into account anatomical cues to identify patients at risk for CO regardless of commissural alignment and compute an alternative, CO-free TAVR rotation angle for those patients.

BACKGROUND

Commissural alignment during TAVR reduces CO risk. However, eccentricity of coronary ostia from the center of the sinus of Valsalva may result in CO even after perfect alignment of TAVR commissures.

METHODS

Baseline computed tomography from TAVR candidates helped identify distance from commissures to the right coronary artery (RCA) and the left coronary artery (LCA). Then, for each case, a virtual valve was simulated with ideal commissural or coronary alignment, and the degree of CO was determined. On the basis of the potential BASILICA (bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction) efficacy, 3 groups were defined: no risk for CO (>35° from neocommissure to coronary ostia), moderate risk (20°-35°), and severe risk (≤20°).

RESULTS

Computed tomographic studies from 107 patients were included. After excluding 7 patients (poor quality or bicuspid valve), 100 patients were analyzed. The RCA showed greater eccentricity compared with the LCA (18.5° [IQR: 3.3°-12.8°] vs 6.5° [IQR: 3.3°-12.8°]; P < 0.001). The mean intercoronary angle was 140.0° ± 18.7° (95% CI: 136.3°-143.7°). Thirty-two patients had moderate to severe risk for CO (≤35°) despite ideal commissural alignment. Greater coronary eccentricity (cutoff for RCA, 24.5°; cutoff for LCA, 19°) and intercoronary angle >147.5° or <103° were associated with greater risk for moderate to severe CO despite commissural alignment (area under the curve: 0.97; 95% CI: 0.91-0.99). If optimal coronary alignment was simulated, this prevented severe CO in all cases and reduced moderate CO from 27% to 5% (P < 0.001).

CONCLUSIONS

One third of patients would have CO during TAVR-in-TAVR despite commissural alignment; a 6-fold decrease in this risk was achieved with optimized coronary alignment. Coronary eccentricity and intercoronary angle were the main predictors.

Calcific Aortic Stenosis-A Review on Acquired Mechanisms of the Disease and Treatments

Calcific aortic stenosis is a progressive disease that has become more prevalent in recent decades. Despite advances in research to uncover underlying biomechanisms, and development of new generations of prosthetic valves and replacement techniques, management of calcific aortic stenosis still comes with unresolved complications. In this review, we highlight underlying molecular mechanisms of acquired aortic stenosis calcification in relation to hemodynamics, complications related to the disease, diagnostic methods, and evolving treatment practices for calcific aortic stenosis.

Simple 2-dimensional anatomic model to predict the risk of coronary obstruction during transcatheter aortic valve replacement

OBJECTIVE

In this study, a 2-dimensional (2D) index relying on preprocedural computed tomography (CT) data was developed to evaluate the risk of coronary obstruction during transcatheter aortic valve replacement (TAVR) procedures.

METHODS

Anatomic measurements from pre-TAVR CT scans were collected in 28 patients among 600 who were flagged as high risk (defined as meeting coronary artery height, h, <14 mm and/or sinus of Valsalva diameter, SOVd, <30 mm) for coronary obstruction. A geometric model derived from these anatomic measurements was used to predict the post-TAVR native cusp apposition relative to the coronary ostium. The distance from the cusp to the coronary ostium, DLC2D, was measured from the geometric model and indexed with the coronary artery diameter, d, to yield a fractional obstruction measure, DLC2D/d.

RESULTS

Twenty-three of 28 high-risk patients successfully underwent TAVR without coronary obstruction, of whom 1 had coronary obstruction and 4 were deemed non-TAVR candidates. DLC2D/d differed significantly between the 2 groups (P < .0018), but neither h nor SOVd did (P > .32). The optimal sensitivity and specificity for DLC2D/d were 85% and occurred at a cutoff of 0.45. The optimal sensitivity and specificity of h and SOVd in this high-risk group were only 60% and 40%, respectively, for cutoffs of h = 10 mm and SOVd = 30.5 mm.

CONCLUSIONS

The 2D geometric model derived in this study shows promise for identifying patients with low-lying coronary ostium and/or small SOVd that may be safely treated with TAVR. DLC2D/d is more predictive of obstruction or poor TAVR candidacy compared with h and SOVd.

Bailout From Sinus Jailing: In-Series TAVR-in-TAVR to Avoid Coronary Flow Obstruction

Redo transcatheter aortic valve replacement (TAVR) may pose the risk of coronary flow obstruction. We report 2 cases of severe TAVR regurgitation due to different physiopathological mechanisms in which TAVR-in-TAVR could be at high risk for sinus sequestration. Both cases were successfully treated by in-series implantation of a second transcatheter heart valve, thus avoiding sinus sequestration. (Level of Difficulty: Intermediate.).

Left Ventricular Outflow Tract Gradient Is Associated With Coronary Artery Obstruction in Children With Williams-Beuren Syndrome

OBJECTIVES

Patients with Williams-Beuren syndrome are associated with a high risk of hemodynamic collapse during sedation and/or anesthesia, presumably due to occult coronary obstruction. The objective of this study was to determine the association between transthoracic echocardiogram findings and the presence of coronary obstruction to examine if coronary obstruction can be predicted by transthoracic echocardiogram before anesthesia.

DESIGN

Retrospective data analysis of patients with Williams-Beuren syndrome who underwent transthoracic echocardiogram, cardiac catheterization, and/or surgical interventions to determine the correlation between echocardiogram findings and the presence of coronary obstruction determined by cardiac catheterization and/or surgery.

SETTING

Single-center university teaching hospital.

PARTICIPANTS

The study included 49 patients with Williams-Beuren syndrome who underwent transthoracic echocardiogram, cardiac catheterization, and/or surgical interventions.

MEASUREMENTS AND MAIN RESULTS

The only variable associated with coronary artery obstruction was the maximum instantaneous gradient (MIG) across the left ventricular outflow tract (LVOT) on a transthoracic echocardiogram. LVOT MIG ≥ 75 mmHg as the optimal cutoff value was associated with coronary artery obstruction (area under the curve 0.659, odds ratio 6.71, 95% CI 1.31-34.35, p = 0.022).

CONCLUSION

LVOT gradient can serve as a good predictor of the presence of coronary obstruction in patients with Williams-Beuren syndrome.

Optimizing self-expandable transcatheter heart valve sizing in patients with small sinus of Valsalva

OBJECTIVES

To evaluate the feasibility and efficacy of transcatheter aortic valve replacement (TAVR) in patients with small sinus of Valsalva (SOV).

BACKGROUND

Patients with small SOV are considered unfavorable for TAVR since it carries risk of coronary obstruction after valve implantation. Therefore, these patients with small SOV were excluded from previous clinical trials.

METHODS

Between February 2017 and February 2019, a total of 139 consecutive patients with severe aortic stenosis (AS) undergoing TAVR were prospectively enrolled in the Tokai Valve Registry. Patients with small SOV who were treated with smaller size of self-expandable transcatheter heart valve (THV) than expected by perimeter-based sizing were included in this study. Eleven patients (7.9%) were included.

RESULTS

Mean age was 86.5 ± 3.8 years and median STS Score was 8.5% (interquartile range: 6.3-12.3%). Device success was accomplished in all patients and no coronary obstruction was observed. No moderate/severe paravalvular leakage, new onset conduction disturbance, and new permanent pacemaker implantation were noted. At 30-day follow-up, mean aortic valve gradient was 6.9 ± 1.7 mmHg and mean indexed aortic valve area was 0.95 ± 0.16 cm² /m² . Prosthetic valve performance was stable at 12-month follow-up. No severe prosthesis patient mismatch was documented at any time point. No in-hospital, 30-day, and 12-month mortality were observed. The median follow-up was 711 days (IQR: 547-803 days), and no patient was lost to follow-up.

CONCLUSIONS

Our preliminary experience suggests favorable safety and efficacy of TAVR utilizing self-expandable THV with intentional down-sizing in patients with severe AS and small SOV in a mid-term follow-up.

Safety and efficacy of repeat transcatheter aortic valve replacement for the treatment of transcatheter prosthesis dysfunction

Introduction: Transcatheter aortic valve replacement (TAVR) has recently expanded toward the treatment of younger patients with lower surgical risk and longer life expectancy. Thus, transcatheter heart valve (THV) durability has become a central issue, and an important increase in the number of TAVR-in-TAVR is expected in the coming years. Areas covered: Overview of the current status of TAVR-in-TAVR for the treatment of THV dysfunction, focusing on safety and efficacy of repeat TAVR procedures. Expert opinion: An accurate analysis of the pre-procedure cardiac computed tomography, incorporating new parameters such as the position of the top of the first THV in relation to the sinotubular-junction, will be necessary to assess the risk of coronary occlusion. Subsequent coronary angiography will be necessary in a proportion of TAVR-in-TAVR patients, but coronary access may be very difficult or even impossible in some of them. Therefore, the choice between TAVR and SAVR in young low-risk patients should incorporate the potential need for treating coronary events at mid- to long-term follow-up. Likewise, the choice of the valve type and the implantation position at the time of the first TAVR procedure should take into account the possibility of TAVR-in-TAVR in the future.Abbreviations ACS: acute coronary syndrome; CO: coronary obstruction; EOA: effective orifice area; SAVR: surgical aortic valve replacement; SVD: structural valve degenerationTAVR: transcatheter aortic valve replacement; THV: transcatheter heart valve.

Risk of Coronary Obstruction and Feasibility of Coronary Access After Repeat Transcatheter Aortic Valve Replacement With the Self-Expanding Evolut Valve: A Computed Tomography Simulation Study

BACKGROUND

The supra-annular leaflet position and tall stent frame of the self-expanding Evolut PRO or Evolut PRO+ transcatheter heart valves (THVs) may cause coronary occlusion during transcatheter aortic valve replacement (TAVR)-in-TAVR and present challenges for future coronary access. We sought to evaluate the risk of TAVR-in-TAVR with Evolut PRO or Evolut PRO+ THVs and the feasibility of future coronary access.

METHODS

The CoreValve Evolut PRO Prospective Registry (EPROMPT; NCT03423459) prospectively enrolled patients with symptomatic severe aortic stenosis to undergo TAVR using a commercially available latest generation self-expanding THV at 2 centers in the United States. Computed tomography was performed 30 days after TAVR, which we used to simulate TAVR-in-TAVR with a second Evolut PRO or Evolut PRO+ THV and evaluate for risk of coronary obstruction and feasibility of future coronary access.

RESULTS

Eighty-one patients enrolled with interpretable computed tomography are reported herein. Computed tomography simulation predicted sinus of Valsalva sequestration and resultant coronary obstruction during future TAVR-in-TAVR in up to 23% of patients. Computed tomography simulation predicted that the position of the pinned THV leaflets would hinder future coronary access in up to 78% of patients after TAVR-in-TAVR.

CONCLUSIONS

Further THV design improvements and leaflet modification strategies are needed to mitigate the risk of coronary obstruction during TAVR-in-TAVR with self-expanding THVs and to facilitate future coronary access. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03423459.

Distribution of C-arm projections in native and bioprosthetic aortic valves cusps: Implication for BASILICA procedures

OBJECTIVES

We sought to document aortic cusps fluoroscopic projections and their distributions using leaflet alignment which is a novel concept to optimize visualization of leaflets and for guiding BASILICA (bioprosthetic or native aortic scallop intentional laceration to prevent coronary artery obstruction) and determine whether these projections were feasible in catheter laboratory.

BACKGROUND

Optimal fluoroscopic projections of aortic valve cusps have not been well described.

METHODS

A total of 128 pre-transcatheter aortic valve replacement (pre-TAVR) computed tomographies (CT) (72 native valves and 56 bioprosthetic surgical valves) were analyzed. Using CT software (3Mensio, Pie medical imaging, the Netherlands), leaflet alignment was performed and the feasibility of these angles, which were defined as rate of obtainable with efforts (within LAO/RAO of 85° and CRA/CAU of 50°) were evaluated.

RESULTS

High feasibility was seen in right coronary cusp (RCC) front view (100%) and left coronary cusp (LCC) side view (99.2%), followed by noncoronary cusp side view (95.3%). In contrast, low feasibility of RCC side view (7.8%) and LCC front view (47.6%) was observed. No statistical differences were seen between the distribution of native valves and bioprosthetic surgical valves. With patient/table tilt of 20°LAO and 10°CRA, the feasibility of RCC side view and LCC front view increased to 43.7 and 85.2%, respectively.

CONCLUSION

Distributions of each cusp's leaflet alignment follows "sigmoid curve" which can provide better understanding of aortic valve cusp orientation in TAVR and BASILICA. RCC side view used in right cusp BASILICA is commonly unachievable in catheter laboratory and may improve with patient/table tilt.

Bioprosthetic Valve Leaflet Displacement During Valve-in-Valve Intervention: An Ex Vivo Bench Study

OBJECTIVES

The aim of this study was to examine the effect of different transcatheter heart valves (THVs) on valve leaflet displacement when deployed within bioprosthetic surgical valves and, thereby, risk for coronary obstruction.

BACKGROUND

Coronary obstruction is a potentially devastating complication during valve-in-valve (ViV) transcatheter aortic valve replacement. Strategies such as provisional stenting and intentional bioprosthetic valve leaflet laceration have been developed to mitigate this risk. Alternatively, the use of a THV that retracts the bioprosthetic leaflet away from the coronary ostium may prevent coronary obstruction.

METHODS

A 25-mm J-Valve, a 26-mm Evolut Pro, and a 23-mm JenaValve were implanted into both a 25-mm Trifecta surgical valve and a 25-mm Mitroflow surgical valve. A 23-mm and a 26-mm SAPIEN 3 were deployed into the Trifecta and Mitroflow, respectively. Displacement of the surgical valve leaflets (retraction vs. expansion) was measured with implantation of each THV by measuring displacement angle and maximal displacement distance.

RESULTS

Within both the Trifecta and Mitroflow valves, implantation of the J-Valve and JenaValve resulted in retraction of the surgical valve leaflets, and placement of the Evolut Pro and SAPIEN 3 resulted in tubular expansion of the surgical valve leaflets. There were significant differences in displacement angles and distances between both the J-Valve and JenaValve and the SAPIEN 3 and Evolut Pro (p < 0.0001).

CONCLUSIONS

ViV implantation with new-generation THVs that directly interact with bioprosthetic valve leaflets results in surgical valve leaflet retraction. This might mitigate the risk for coronary obstruction in selected cases of ViV transcatheter aortic valve replacement and also facilitate coronary reaccess after ViV TAVR.

Coronary Protection to Prevent Coronary Obstruction During TAVR: A Multicenter International Registry

OBJECTIVES

The aim of this study was to investigate the safety and efficacy of coronary protection by preventive coronary wiring and stenting across the coronary ostia in patients at high risk for coronary obstruction after transcatheter aortic valve replacement (TAVR).

BACKGROUND

Coronary obstruction following TAVR is a life-threatening complication with high procedural and short-term mortality.

METHODS

Data were collected retrospectively from a multicenter international registry between April 2011 and February 2019.

RESULTS

Among 236 patients undergoing coronary protection with preventive coronary wiring, 143 had eventually stents implanted across the coronary ostia after valve deployment. At 3-year follow-up, rates of cardiac death were 7.8% in patients receiving stents and 15.7% in those not receiving stents (adjusted hazard ratio: 0.42; 95% confidence interval: 0.14 to 1.28; p = 0.13). There were 2 definite stent thromboses (0.9%) in patients receiving stents, both occurring after TAVR in "valve-in-valve" procedures. In patients not receiving stents, there were 4 delayed coronary occlusions (DCOs) (4.3%), occurring from 5 min to 6 h after wire removal. Three cases occurred in valve-in-valve procedures and 1 in a native aortic valve procedure. Distance between the virtual transcatheter valve and the protected coronary ostia <4 mm was present in 75.0% of patients with DCO compared with 30.4% of patients without DCO (p = 0.19).

CONCLUSIONS

In patients undergoing TAVR at high risk for coronary obstruction, preventive stent implantation across the coronary ostia is associated with good mid-term survival rates and low rates of stent thrombosis. Patients undergoing coronary protection with wire only have a considerable risk for DCO.

Acute coronary artery obstruction following surgical repair of congenital heart disease

OBJECTIVES

Acute coronary artery obstruction is a rare complication of congenital heart disease surgery but imposes a high burden of morbidity and mortality. Previous case series have described episodes in specific congenital heart lesions or surgical repairs but have not examined the complication in all-comers to congenital heart surgery. We hypothesize that shorter time from a clinically recognized postoperative sentinel event suggestive of coronary ischemia to diagnosis of coronary obstruction is associated with improved clinical outcomes.

METHODS

This was a single-center, retrospective review of patients diagnosed with acute coronary artery obstruction by angiography following surgical repair of congenital heart disease between January 2000 and June 2016.

RESULTS

In total, 34 patients were identified. The most common procedures associated with coronary artery obstruction were the Norwood procedure, arterial switch operation, and aortic valve repair/replacement. In total, 79% required mechanical circulatory support, 41% died, and 27% were listed for heart transplant. Patients who died or were listed for heart transplant had longer median sentinel-event-to-cardiac-catheterization time (28 [6-168] hours vs 10 [3-56] hours, P = .001), and longer median sentinel-event-to-intervention time (32 [11-350] hours vs 13 [5-59] hours, P = .003). Patients with hypoplastic left heart syndrome were at greater risk of death or transplant listing (odds ratio, 9.23, P = .03).

CONCLUSIONS

Time from clinically relevant postoperative sentinel event to diagnosis of coronary artery obstruction by angiography was associated with transplant-listing-free survival. Clinicians should maintain a high index of suspicion for coronary obstruction and consider early catheterization and coronary angiography for patients in whom post-operative coronary compromise is suspected.

Valve-in-Valve Challenges: How to Avoid Coronary Obstruction

Coronary obstruction is a rare but life-threatening complication in patients undergoing transcatheter aortic valve replacement (TAVR). Aortic valve-in-valve (VIV) procedures to treat failed surgical bioprosthesis is associated with ~6-fold higher risk for coronary obstruction in certain situations. The primary mechanism consists in the occlusion of the coronary ostium by the dislodged leaflet from the bioprosthesis after deployment of the transcatheter heart valve (THV), which most commonly occurs during the index procedure, but in up to 1/3 of cases a delayed presentation ensues. The clinical presentation consists of severe hypotension and ECG changes in most of the patients, with very high mortality rates. Therefore, pre-procedural multi-slice computed tomography is crucial for identifying high-risk features, such as low coronary heights, shallow sinuses of Valsalva, and short virtual THV to coronary ostial distance (VTC). Also, some models of surgical bioprosthesis present an increased risk for this dreadful complication. Preemptive protective strategies with coronary wiring, with or without placement of an undeployed stent, could mitigate the risks associated with this complication in high-risk patients, even though studies are lacking. This review aims to take a clinical perspective on the challenges in avoiding this complication during VIV procedures.

Modeling risk of coronary obstruction during transcatheter aortic valve replacement

OBJECTIVE

In this study we aimed to evaluate risk of coronary obstruction during transcatheter aortic valve replacement and develop improved criteria based on computational modeling.

METHODS

Patient specific 3-dimensional models were constructed and validated for 28 patients out of 600 patients who were flagged as high risk for coronary obstruction (defined as meeting coronary ostium height < 14 mm and/or sinus of Valsalva diameter [SOVd] < 30 mm). The models consisted finite element analysis to predict the post- transcatheter aortic valve replacement native cusp apposition relative to the coronary ostium and were validated in vitro. The distance from cusp to coronary ostium (DLC) was derived from the 3-dimensional models and indexed with the coronary artery diameter to yield a fractional obstruction measure (DLC/d).

RESULTS

Twenty-two out of 28 high-risk patients successfully underwent transcatheter aortic valve replacement without coronary obstruction and 6 did not. DLC/d between the 2 groups was significantly different (P < .00078), whereas neither coronary ostium height nor SOVd were significantly different (P > .32). A cutoff of DLC/d < 0.7 was predictive with 100% sensitivity and 95.7% specificity. The optimal sensitivity and specificity of coronary ostium height and SOVd in this high-risk group was only 60% and 40%, respectively, for cutoff coronary ostium height of 10 mm and SOVd of 30.5 mm.

CONCLUSIONS

Three-dimensional modeling has the potential to enable more patients to be safely treated with transcatheter aortic valve replacement who have a low-lying coronary ostium or small SOVd. DLC/d is more predictive of obstruction than coronary ostium height and SOVd.

A Case of Acute Left Main Coronary Obstruction Following Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) is a highly effective procedure in selected patients with severe degenerative aortic valve stenosis at high risk for conventional surgery. Coronary occlusion is a periprocedural life-threatening complication that despite its low frequency (˂1%) is poorly predictable and requires immediate diagnosis and treatment. Herein, we report a coronary obstruction after transcatheter implantation of valve prosthesis, followed by coronary intervention with successful recanalization.

Incidence and predictors of coronary obstruction following transcatheter aortic valve implantation in the real world

OBJECTIVES

Coronary obstruction (CO) is a rare but serious complication of transcatheter aortic valve implantation (TAVI). There are very limited data regarding CO following TAVI. The aim of this study was to evaluate the incidence and outcomes of CO after TAVI and identify the predictors including the valve type.

METHODS

Between October 2006 and March 2015, 1,203 TAVI cases were performed in our institution. Of them, 814 cases whose coronary height was measured using computed tomography for screening were analyzed in this study.

RESULTS

The Edwards SAPIEN/SAPIEN XT (S/XT) was used in 427 (52.4%) cases, the CoreValve in 265 (32.6%), and the S3 in 122 (15.0%). CO occurred in 8 (1.0%) cases, 1.6% with S/XT, 0.4% with CoreValve, and 0% with S3. All instances of CO occurred at the left coronary artery. The 30-day mortality was significantly higher in cases of CO (37.5% vs. 5.8%, P = 0.010). The frequency of CO tended to be lower in recipients of the CoreValve (0.4%) and S3 (0%) compared with the S/XT (1.6%) (P = 0.188 for CoreValve vs. S/XT, P = 0.022 for S3 vs. S/XT).

CONCLUSIONS

CO has poor outcomes and identification of patients at risk of CO to take preventive measures is crucial. The preliminary data showing that the occurrence of CO is low in patients receiving the S3 despite increased prosthesis height need further confirmation. © 2017 Wiley Periodicals, Inc.