Update on transcatheter aortic valve replacement

Association of general anesthesia exposure with risk of postoperative delirium in patients receiving transcatheter aortic valve replacement: a meta-analysis and systematic review

The aim of this meta-analysis was to assess the association of general anesthesia (GA) exposure with the risk of POD in this patient population. Databases including Medline, EMBASE, Cochrane library, and Google Scholar were searched from inception to December 2022. Analysis of 17 studies published between 2015 and 2021 involving 10,678 individuals revealed an association of GA exposure with an elevated risk of POD [odd ratio (OR) = 1.846, 95% CI 1.329 to 2.563, p = 0.0003, I2 = 68.4%, 10,678 patients]. Subgroup analysis of the diagnostic methods also demonstrated a positive correlation between GA exposure and POD risk when validated methods were used for POD diagnosis (OR = 2.199, 95% CI 1.46 to 3.31, p = 0.0002). Meta-regression analyses showed no significant impact of age, male proportion, and sample size on the correlation between GA and the risk of POD. The reported overall incidence of POD from the included studies regardless of the type of anesthesia was between 0.8 and 27%. Our meta-analysis showed a pooled incidence of 10.3% (95% CI 7% to 15%). This meta-analysis suggested an association of general anesthesia with an elevated risk of postoperative delirium, implying the necessity of implementing appropriate prophylactic strategies against this complication when general anesthesia was used in this clinical setting.

New stent for transapical mitral valve replacement in acute swine experiment

Background

Many patients with mitral regurgitation are denied open-heart surgery due to perceived high risk. Transcatheter mitral valve replacement is a therapeutic alternative for patients at high surgical risk. This study aimed to assess the feasibility of a new self-expanding valved stent for transcatheter mitral valve replacement via apex in an acute animal model.

Methods

Eight porcine experiments were performed in the acute study. A left thoracotomy was performed, and the new self-expanding transcatheter valved stent was deployed under fluoroscopic guidance in the native mitral annulus via apex. Hemodynamic data were recorded before and after implantation. Mitral annulus diameter and valve area were measured using echocardiography. Transvalvular and left ventricular outflow tract pressure gradients were measured using invasive methods.

Results

Seven animals underwent successful transapical mitral valve replacement; the implantation was unsuccessful in one animal. The mean procedure time, defined from placement to tightening of the purse-string suture, was 17.14 ± 7.86 min. Hemodynamic data before and after transapical mitral valve replacement showed no difference in statistical analysis. The mean diameter of the self-expanding device after implantation was 2.58 ± 1.04 cm; the mean functional area was 2.70 ± 0.26 cm². Trace-to-mild central and paravalvular leaks were detected in 7 valves. The mean pressure gradient across the self-expanding device was 2.00 ± 0.82 mmHg; the corresponding gradient across the LVOT was 3.28 ± 1.11 mmHg. Postmortem evaluation confirmed precise device positioning in 7 animals with no signs of LVOT obstruction.

Conclusion

Transcatheter mitral replacement of the new valved stent was confirmed feasible in acute preclinical models. The new stent reveals optimal design parameters.

Antithrombotic selection in patients undergoing transcatheter aortic valve replacement

PURPOSE

Clinical controversy regarding the most appropriate antithrombotic regimen after transcatheter aortic valve replacement remains. Current evidence, guidelines, and recommendations are discussed.

SUMMARY

Antithrombotic selection following transcatheter aortic valve replacement depends on a variety of patient-specific factors. For patients without a preexisting indication for anticoagulation, initial trials employed dual antiplatelet therapy as the postprocedural therapy of choice. Newer studies in this patient population, however, suggest single antiplatelet therapy reduces bleeding events without sacrificing ischemic protection. In patients with a preexisting indication for anticoagulation, warfarin plus single antiplatelet therapy, as opposed to triple antithrombotic therapy, offered similar ischemic protection while reducing clinically significant bleeding. Warfarin monotherapy was associated with a further reduction in bleeding events. One trial demonstrated the safety and efficacy of using apixaban in patients with concomitant atrial fibrillation; however, routine use of rivaroxaban increased adverse cardiac and bleeding events, leaving the utility of direct-acting oral anticoagulants in question.

CONCLUSION

Available evidence and current guidelines point to a lack of consensus regarding antithrombotic selection after transcatheter aortic valve replacement. Patient-specific factors and comorbidities must be considered when tailoring therapy, with an emphasis on balancing thrombotic and bleeding risks.

A validated computational framework to predict outcomes in TAVI

Transcatheter aortic valve implantation (TAVI) still presents complications: paravalvular leakage (PVL) and onset of conduction abnormalities leading to permanent pacemaker implantation. Our aim was testing a validated patient-specific computational framework for prediction of TAVI outcomes and possible complications. Twenty-eight TAVI patients (14 SapienXT and 14 CoreValve) were retrospectively selected. Pre-procedural CT images were post-processed to create 3D patient-specific implantation sites. The procedures were simulated with finite element analysis. Simulations' results were compared against post-procedural clinical fluoroscopy and echocardiography images. The computational model was in good agreement with clinical findings: the overall stent diameter difference was 2.6% and PVL was correctly identified with a post-processing algorithm in 83% of cases. Strains in the implantation site were studied to assess the risk of conduction system disturbance and were found highest in the patient who required pacemaker implantation. This study suggests that computational tool could support safe planning and broadening of TAVI.

Transcatheter mitral valve replacement with the NaviGate stent in a preclinical model

AIMS

The aim of this study was to test the feasibility of transcatheter mitral valve implantation of the NaviGate device in acute and chronic preclinical models.

METHODS AND RESULTS

We evaluated NaviGate valved stent implantation in the mitral position in an acute swine model (n=24, ≤5 days) through three different approaches - transatrial, transapical, and transseptal - and in a chronic swine model (n=12, >10 days) through a transatrial approach. The NaviGate implantation procedures were successful in 83% of the acute model studies (n=20) and 83% of the chronic model studies (n=10). Echocardiographic assessment showed low gradient across the valved stent (mean gradient <3 mmHg) and the left ventricular outflow tract (mean gradient <6 mmHg). Post implantation, there was no mitral regurgitation (MR) in 75% (n=15) of the acute studies and mild MR in 25% (n=5). In the chronic model, there was no MR in 60% (n=6) and mild MR in 40% (n=4). The implantation procedure was aborted in four acute studies due to inferior vena cava injury and in two chronic studies due to prosthesis-annulus mismatch.

CONCLUSIONS

In preparation for clinical application, transcatheter mitral implantation of the NaviGate valved stent was proved feasible in acute and chronic preclinical models. The three featured delivery approaches are of particular value for high-risk patients with functional MR and challenging vascular access.

Impact of sheath diameter of different sheath types on vascular complications and mortality in transfemoral TAVI approaches using the Proglide closure device

OBJECTIVE

Evaluation of the impact of the sheath diameter on vascular complications and mortality in transfemoral aortic valve implantation.

METHOD

Between 2012 and 2014, 183 patients underwent the procedure using a sheath diameter of 18-24 F. This collective was divided into two groups: group 1, with a sheath diameter of 18F (G1, n = 94), consisted of patients with 18F Medtronic Sentrant and 18 F Direct Flow sheaths, and group 2 with a sheath diameter of 19-24 F (G2, n = 89) consisted of patients with Edwards expandable e-sheath and Solopath sheaths. Perclose-Proglide® was used as a closure device in all patients.

RESULTS

G1 had significantly more female patients (64.9% vs. 46.1% in G2, p = 0.01) and the average BMI was lower (26 ± 4.5% vs. 27.4 ± 4.7%, p = 0.03). There was no significant difference in the incidence of major and minor vascular complications (G1: 12.8% vs. G2: 12.4%, p = 0.9). 30-day mortality was similar in both groups (G1: 6.4 ± 2.5% [95% CI: 0.88-0.98], G2: 3.7 ± 1.9% [95% CI: 0.92-0.99]. The Kaplan Meier analysis of survival revealed no significant differences either.

CONCLUSION

The difference in sheath diameter had no effect on either incidence or severity of vascular complications. There was no impact on mortality either.

First-in-Man Transcervical Surgical Aortic Valve Replacement Using the CoreVista System

OBJECTIVE

This study aimed to evaluate a novel device system for surgical aortic valve replacement (SAVR) using a unique new less invasive access approach. The hypothesis is that SAVR can be performed through a short transverse incision in the neck, similar to that used for transcervical thymectomy avoiding chest disruption.

METHODS

A new device system was developed to provide retraction, step-by-step illumination, and on-screen visualization for the new approach. Preliminary feasibility studies were performed in cadavers. Comprehensive risk analysis was performed, and training was implemented in Thiel preserved cadavers. For the first-in-man clinical case, a 63-year-old woman with symptomatic critical aortic stenosis (The Society of Thoracic Surgeons risk, 11%) and heavily calcified aortic valve was selected. A short transverse incision was made in the neck; the device was introduced, and the sternum was elevated; femorofemoral cardiopulmonary bypass was established; substernal dissection was guided by the sequenced illumination, and high-definition visualization was provided by the device, allowing for optimal exposition of the aorta and aortic valve; and a 23-mm Medtronic ENABLE sutureless valve prosthesis was implanted. Procedure success was evaluated according to the standardized composite end point definition of "device success" proposed by the Valve Academic Research Consortium.

RESULTS

Access, delivery, and deployment of the valve prosthesis were successful. The correct position and intended performance of the valve were demonstrated (mean gradient, 6 mm Hg; aortic valve area, 2.5 cm) with the absence of moderate or severe prosthetic aortic regurgitation. Only one valve prosthesis was used.

CONCLUSIONS

Transcervical SAVR with sutureless valve is feasible using this novel access system. The new approach has potential to offer patients substantially shorter stay and fewer, less serious complications, as has been observed in transcervical thymectomy. Further studies are merited.

In Vitro Hydrodynamic Assessment of a New Transcatheter Heart Valve Concept (the TRISKELE)

This study presents the in vitro hydrodynamic assessment of the TRISKELE, a new system suitable for transcatheter aortic valve implantation (TAVI), aiming to mitigate the procedural challenges experienced with current technologies. The TRISKELE valve comprises three polymeric leaflet and an adaptive sealing cuff, supported by a novel fully retrievable self-expanding nitinol wire frame. Valve prototypes were manufactured in three sizes of 23, 26, and 29 mm by automated dip-coating of a biostable polymer, and tested in a hydrodynamic bench setup in mock aortic roots of 21, 23, 25, and 27 mm annulus, and compared to two reference valves suitable for equivalent implantation ranges: Edwards SAPIEN XT and Medtronic CoreValve. The TRISKELE valves demonstrated a global hydrodynamic performance comparable or superior to the controls with significant reduction in paravalvular leakage. The TRISKELE valve exhibits enhanced anchoring and improved sealing. The valve is currently under preclinical investigation.

Health-related quality-of-life after transapical transcatheter aortic valve implantation

PURPOSE

Transcatheter aortic valve implantation (TA-TAVI) is a well-established treatment for aortic valve stenosis in high-risk patients and indications have been continuously expanding to also include intermediate-risk patients. However, in low-risk patients, experiences are still sparse and although clinical outcomes have been shown favorable results, HRQoL has remained unexplored. The aim of this report was to describe the long-term health-related quality-of-life (HRQoL) in low-risk patients randomized to TA-TAVI or surgical aortic valve replacement (SAVR).

METHODS

In a prospective, randomized trial, patients with aortic valve stenosis were randomized to either TA-TAVI or SAVR. TA-TAVI was performed through a mini thoracotomy with the introduction of prosthesis via the apex of the heart and antegradely advancement over the pre-dilated native valve. SAVR was performed during cardiopulmonary bypass with resection of the native valve and replacement with a prosthesis valve through a median sternotomy. Afterwards, patients were followed yearly with echocardiography and HRQoL assessment.

RESULTS

A total of 58 patients were included; 29 patients for TA-TAVI and 29 patients for SAVR. The only difference in HRQoL was found in the physical component summary after 1 year; 44 ± 9 in the TA-TAVI group compared with 36 ± 9 in the SAVR group, p = .03. There were no differences in any of the remaining timepoints in neither physical nor mental component summary, p = .19 and p = .98, respectively, and there were no differences in survival during the 5 years.

CONCLUSIONS

In low-risk patients with aortic valve stenosis undergoing TA-TAVI, no differences appeared in HRQoL compared with SAVR during a 5-year follow-up period.

[Aortic valve replacement in the elderly]

The treatment of severe symptomatic aortic valve stenosis by conventional aortic valve replacement (AVR) or by transcatheter aortic valve implantation (TAVI) has a good perinterventional prognosis even for patients of advanced age. Having a heart team select the best management strategies based on current guidelines for each individual patient is essential for success. Especially in elderly and increasingly multimorbid patients with sometimes severe preconditions, the detection of functional deficits is relevant not only for the mortality but also for perioperative and postoperative complications as well as the functional outcome. Various methods of geriatric assessment are important supplements to standard risk scores. The aim is to implement targeted interventions to minimize the risk factors and to improve the prognosis for elderly patients. The aim of this article is to provide an overview of the current therapy options for aortic valve replacement and to summarize current aspects of treatment options for elderly patients.

[TAVI in Germany. What have we learned from current studies?]

Transcatheter aortic valve implantation (TAVI) has become an established treatment for symptomatic aortic valve stenosis in inoperable patients and high-risk patients. In Germany the TAVI procedure has now surpassed the annual numbers of isolated surgical aortic valve replacement with a recent trend towards treatment of intermediate-risk patients; however, before TAVI can also be used in patients with lower surgical risk, studies are required to demonstrate the safety and efficacy of this method for this patient population.

Transapical Implantation of a 2nd-Generation JenaValve Device in Patient with Extremely High Surgical Risk

Transcatheter Aortic Valve Replacement (TAVR) is performed in patients who are poor surgical candidates. Many patients have inadequate femoral access, and alternative access sites have been used such as the transapical approach discussed in this paper. We present an elderly and fragile patient not suitable for surgery for unacceptable high risk, including poor ventricular function, previous myocardial infarction with percutaneous coronary intervention, pericardial effusion, and previous cardiac surgery with replacement of mechanical mitral valve. Transapical aortic valve replacement with a second-generation self-expanding JenaValve is performed. The JenaValve is a second-generation transapical TAVR valve consisting of a porcine root valve mounted on a low-profile nitinol stent. The valve is fully retrievable and repositionable. We discuss transapical access, implantation technique, and feasibility of valve implantation in this extremely high surgical risk patient.