An update on complications associated with transcatheter aortic valve implantation: stroke, paravalvular leak, atrioventricular block and perforation

CardioVision: A fully automated deep learning package for medical image segmentation and reconstruction generating digital twins for patients with aortic stenosis

Aortic stenosis (AS) is the most prevalent heart valve disease in western countries that poses a significant public health challenge due to the lack of a medical treatment to prevent valve calcification. Given the aging population demographic, the prevalence of AS is projected to rise, resulting in a progressively significant healthcare and economic burden. While surgical aortic valve replacement (SAVR) has been the gold standard approach, the less invasive transcatheter aortic valve replacement (TAVR) is poised to become the dominant method for high- and medium-risk interventions. Computational simulations using patient-specific models, have opened new research avenues for optimizing emerging devices and predicting clinical outcomes. The traditional techniques of generating digital replicas of patients' aortic root, native valve, and calcification are time-consuming and labor-intensive processes requiring specialized tools and expertise in anatomy. Alternatively, deep learning models, such as the U-Net architecture, have emerged as reliable and fully automated methods for medical image segmentation. Two-dimensional U-Nets have been shown to produce comparable or more accurate results than trained clinicians' manual segmentation while significantly reducing computational costs. In this study, we have developed a fully automatic AI tool capable of reconstructing the digital twin geometry and analyzing the calcification distribution on the aortic valve. The developed automatic segmentation package enables the modeling of patient-specific anatomies, which can then be used to simulate virtual interventional procedures, optimize emerging prosthetic devices, and predict clinical outcomes.

Intracoronary Pacing during "Chimney Technique" in Transcatheter Aortic Valve-in-Valve Implantation: An Alternative Temporary Rapid Ventricular Stimulation?

Temporary rapid ventricular pacing (TRVP) is required during transcatheter aortic valve implantation (TAVI) in order to reduce cardiac output and to facilitate balloon aortic valvuloplasty, prosthesis deployment, and post-deployment balloon dilation. The two most frequently used TRVP techniques are right endocardial (RE)-TRVP and retrograde left endocardial temporary rapid ventricular pacing (RLE)-TRVP. The first one could be responsible for cardiac tamponade, one of the most serious procedural complications during TAVI, while the second one could often be unsuccessful. Intracoronary (IC)-TRVP through a coronary guidewire has been described as a safe and efficient procedure that could avoid such complications. We describe two clinical cases in which IC-TRVP has been effectively used during valve-in-valve TAVI with coronary protection via the "chimney technique", after unsuccessful RLE-TRVP.

Three-dimensional printing for assessment of paravalvular leak in transcatheter aortic valve implantation

Background

Three-dimensional (3D) models have the unique ability to replicate individualized cardiac anatomy and may therefore provide clinical benefit. Transcatheter aortic valve implantation (TAVI) currently relies on preoperative imaging for accurate valve sizing, type of valve used, and avoidance of complications. Three-dimensional (3D) modelling may provide benefit for optimal preoperative TAVI planning. The goal of this study is to assess the utility of 3D modelling in the prediction of paravalvular leak (PVL) post TAVI.

Methods

Retrospective analysis of five patients who underwent TAVI at our center. Pre-operative cardiac gated CT images were utilized to create a 3D printed model with true size aortic root dimensions, including the coronary artery ostium location and left ventricular outflow tract. Deployment of the corresponding model and size TAVI valve into the created 3D model at a similar depth of implantation via fluoroscopy was performed for each patient. Degree of PVL was assessed using a closed system with water infusion under pressure over a duration of 5 s. Correlation was made between the volume obtained in the closed loop model during the pressurized period and the degree of PVL reported on the patients post TAVI placement on transthoracic echocardiogram.

Results

One female, and four males (age in years ranged from 68 to 87) underwent successful TAVI (0% 30-day mortality). PVL on post procedure TTE ranged from none to trivial. Successful deployment of TAVI valves inside the 3D model occurred in all cases. The average volume of water collected on three trials over 5 s ranged between 19.1–24.1 ml A multivariate linear regression showed significant association between the degree of PVL reported on post-operative transthoracic echocardiogram and the amount of volume detected in the 3D model (difference: -3.9657, 95% CI: (− 4.6761,-3.2554), p < 0.001).

Conclusions

Our experiments show that replicated 3D models have potential clinical utilization in predicting PVL in the TAVI population. Future research into the role of 3D modelling in the field of TAVI should continue to be explored.

A novel technique to avoid perforation of the right ventricle by the temporary pacing lead during transcatheter aortic valve implantation

Cardiac tamponade is a life-threatening complication during transcatheter aortic valve implantation (TAVI), often caused by perforation of the right ventricle (RV) by the temporary pacemaker used for rapid pacing during valve deployment. We aimed to assess the feasibility of performing rapid pacing while maintaining inflation of the pacing lead balloon in the RV during TAVI. Among 749 consecutive patients who underwent TAVI with SAPIEN XT valves between October 2013 and July 2015, 726 treated using rapid pacing with a transvenous balloon-tip lead were enrolled in our study, and were stratified into three groups according to the extent of balloon inflation in the RV as follows: full inflation (n = 100), partial inflation (n = 196), and deflation (n = 430). We compared the following clinical outcomes: pacing lead-related RV perforation, rapid pacing failure, valve malpositioning due to rapid pacing failure, device success, and 30-day mortality. Pacing lead-related RV perforation occurred only in patients in the deflation group (6 cases, 1.4%), but the differences among the groups were not statistically significant (p = 0.13). Rapid pacing failure, but no valve malpositioning, occurred most frequently in patients in the full inflation group (4.0% vs. 0.5% in the other groups, p = 0.004). The rate of device success (> 94%) and the 30-day mortality (2.0%) were similar among the three groups. Partial inflation of the balloon of the pacing lead may reduce the risk of RV perforation without increasing the risk of pacing failure or valve malpositioning.

Effect of transcatheter aortic valve implantation on intraoperative left ventricular end-diastolic pressure

Transcatheter aortic valve implantation (TAVI) for patients with aortic stenosis is a less invasive alternative to surgical aortic valve replacement. Despite this, careful anesthetic management, especially strict control of blood pressure and fluid management, is necessary. During TAVI, normalization of left ventricular afterload due to aortic balloon valvuloplasty and prosthetic valve deployment is expected to result in rapid improvement of systolic function and consequent improvement in diastolic function. However, the early effect of TAVI on left ventricular diastolic function is less clear. We hypothesized that TAVI induces a rapid decrease in left ventricular end-diastolic pressure (LVEDP) after valve deployment. This retrospective observational study included 71 patients who had undergone TAVI using the transfemoral approach with a balloon-expandable valve under general anesthesia. Intraoperative LVEDP was measured using an intracardiac catheter. The severity of residual aortic regurgitation (AR) was assessed using the Sellers criteria. The mean (SD) LVEDP was 17.8 (5.3) mmHg just before TAVI and increased significantly to 27.3 (8.2) mmHg immediately after prosthetic valve deployment (p < 0.0001). The change in LVEDP was 8.7 (8.6) mmHg in patients with low residual AR (Sellers ≤1) and 11.0 (7.1) mmHg in those with high residual AR (Sellers ≥2); however, this difference was not significant. No correlation was found between the LVEDP change and intraoperative fluid balance. In conclusion, LVEDP increased significantly in the early period after valve deployment during TAVI, regardless of residual AR severity. It was suggested that the tolerability of fluid load could be reduced at that time.

Percutaneous transcatheter aortic valve implantation for degenerated surgical bioprostheses: the first case series in Asia with one-year follow-up

INTRODUCTION

Percutaneous transcatheter aortic valve implantation (TAVI) has become an established therapy for inoperable and high-surgical-risk patients with severe aortic stenosis. Although TAVI in patients with degenerated surgical aortic bioprostheses (i.e. valve-in-valve TAVI) is increasingly reported in Western studies, such data is lacking in Asian patients. We describe the initial experience of valve-in-valve TAVI in Asia.

METHODS

Eight patients who underwent valve-in-valve TAVI due to degenerated aortic bioprostheses were enrolled. The mechanism of bioprosthetic valve failure was stenotic, regurgitation or mixed. All procedures were performed via transfemoral arterial access, using the self-expanding CoreValve prosthesis or balloon-expandable SAPIEN XT prosthesis.

RESULTS

The mean age of the patients was 71.6 ± 13.2 years and five were male. Mean duration to surgical bioprosthesis degeneration was 10.2 ± 4.1 years. Valve-in-valve TAVI was successfully performed in all patients. CoreValve and SAPIEN XT prostheses were used in six and two patients, respectively. There were no deaths, strokes or permanent pacemaker requirement at 30 days, with one noncardiac mortality at one year. All patients experienced New York Heart Association functional class improvement. Post-procedure mean pressure gradients were 20 ± 11 mmHg and 22 ± 8 mmHg at 30 days and one year, respectively. Residual aortic regurgitation (AR) of more than mild severity occurred in one patient at 30 days. At one year, only one patient had mild residual AR.

CONCLUSION

In our experience of valve-in-valve TAVI, procedural success was achieved in all patients without adverse events at 30 days. Good clinical and haemodynamic outcomes were sustained at one year.