Transcatheter aortic valve replacement: clinical safety and performance data

Safety and performance of the Vienna self-expandable transcatheter aortic valve system: 6-month results of the VIVA first-in-human feasibility study

Background

The novel Vienna TAVI system is repositionable and retrievable, already pre-mounted on the delivery system, eliminating the need for assembly and crimping of the device prior to valve implantation.

Aims

The purpose of this first-in-human feasibility study was to determine the safety, feasibility, clinical and hemodynamic performance of the Vienna TAVI system at 6-month follow-up. (ClinicalTrials.gov identifier NCT04861805).

Methods

This is a prospective, non-randomized, single-arm, single-center, first-stage FIH feasibility study, which is followed by a second-stage pivotal, multicenter, multinational study in symptomatic patients with severe aortic stenosis (SAS). The first-stage FIH study evaluated the safety and feasibility, clinical and hemodynamic performance of the device in 10 patients with SAS based on recommendations by the VARC-2.

Results

All patients were alive at 3-month follow-up. 1 non-cardiovascular mortality was reported 5 months after implantation. There were no new cerebrovascular events, life-threatening bleeding or conduction disturbances observed at 6-month follow-up. The mean AV gradient significantly decreased from 48.7 ± 10.8 to 7.32 ± 2.0 mmHg and mean AVA increased from 0.75 ± 0.18 to 2.16 ± 0.42 cm² (p < 0.00001). There was no incidence of moderate or severe total AR observed. In the QoL questionnaires, the patients reported a significant improvement from the baseline 12-KCCQ mean score 58 ± 15 to 76 ± 20. NYHA functional class improved in two patients, remained unchanged in one patient. There was an increase in mean 6-min-walk distance from baseline 285 ± 97 to 347 ± 57 m.

Conclusions

This study demonstrates that using Vienna TAVI system has favourable and sustained 6-month safety and performance outcomes in patients with symptomatic severe aortic stenosis.

Dual Antiplatelet Therapy vs. Single Antiplatelet Therapy After Transcatheter Aortic Valve Replacement: An Updated Systematic Review and Meta-Analysis

Background: Although mainstream guidelines recommend dual antiplatelet therapy (DAPT) with aspirin and clopidogrel in patients following transcatheter aortic valve replacement (TAVR), it is not evidence-based. We aim to investigate the safety and efficacy of DAPT vs. single antiplatelet therapy (SAPT) after TAVR, and review updated evidence. Methods: We systematically searched PubMed, Embase, and Cochrane for studies comparing DAPT to SAPT after TAVR from inception to November 30, 2020. The primary outcome was major adverse cardiac and cerebrovascular events, including all-cause mortality, cardiovascular death, myocardial infarction (MI), stroke, and major or life-threatening bleeding (LTB). Subgroup analysis was performed according to study type (randomized control trials vs. observational studies) using a fixed-effects model. The quality of evidence was assessed by two scoring systems and GRADE (Grading of Recommendations Assessment, Development, and Evaluation). Results: Twelve studies of 20,766 patients were included in our meta-analysis. Compared with SAPT, DAPT was associated with an increased risk for combined life threatening and major bleeding [OR 1.73 (1.19-2.51), p = 0.004] after TAVR. Such a difference was largely driven by major bleeding [OR 2.29 (1.68-3.11), p < 0.001]. There were no significant differences on major adverse cardiovascular events (MACE) [OR 1.19 (0.99-1.44), p = 0.07], cardiovascular mortality [OR 1.46 (0.93-2.30), p = 0.10], and stroke [OR 0.97 (0.80-1.16), p = 0.71]. Conclusions: Compared with SAPT, post-TAVR DAPT was associated with increased risks of major or life-threatening bleeding without additional benefits of reducing thrombotic events. Future guidelines for post-TAVR antiplatelet strategy are expected to be updated as new high-quality evidence emerges. Systematic Review Registration: PROSPERO, Identifier: CRD42021230075.

Outcomes of 1,098 Patients Following Transcatheter Aortic Valve Implantation: A Statewide Population-Linkage Cohort Study

BACKGROUND

The increasing implementation of transcatheter aortic valve implantation (TAVI) in Australia warrants real-world data on the prevalence and outcomes of these patients. The aim of this study is to describe trends in case-volumes of TAVI in New South Wales (NSW), Australia and associated mortality outcomes.

METHODS

From the Centre of Health Record Linkage registry, all NSW residents who underwent TAVI between 5 June 2013 and 30 June 2018 were identified. Cause-specific mortality was tracked from the statewide death registry. Temporal trends in case-volumes between 2013 and 2018 were assessed by linear regression. Binary logistic regression was used to compare differences in in-hospital and 30-day mortality, while Cox proportional hazards regression was used to compare mortality beyond 30 days.

RESULTS

Case-volumes increased from 30 in 2013 to 345 by 2017. The cohort comprised 1,098 persons (mean[±SD] age: 83.3±7.7 yrs). Cumulative in-hospital, 180-day and at end-of-study (mean: 1.8±1.2 yrs) all-cause mortality were 1.3% (n=14), 4.9% (n=54) and 20.3% (n=224) respectively. Heart failure (14.3%, n=2), myocardial infarction (14.3%, n=2), and sepsis (14.3%, n=2) were the primary causes of in-hospital death. Post-discharge, sepsis (25.2%, n=53) was the main cause-specific death, while combined cardiovascular deaths accounted for 46% (n=97), mostly from heart failure (n=35). Heart failure, chronic kidney disease, and requirement for ventilation post-TAVI were independent predictors of in-hospital death and at 180 days. TAVI procedure in low-volume public centres was a predictor of mortality at 180 days.

CONCLUSION

The number of TAVI procedures increased 10-fold between 2013 and 2017 state-wide, with mortality rates comparable to international cohorts at short and medium-term follow-up. Pre-existing comorbidities and site-specific caseloads may be important determinants of outcome, emphasising the importance of appropriate patient selection and treating centre.