Valve-in-valve implantation of a novel and small self-expandable transcatheter heart valve in degenerated small surgical bioprostheses: The Hamburg experience

Contemporary Outcome Trends in Transcatheter Aortic Valve-in-Valve Implantation Versus Redo Aortic Valve Replacement

As valve-in-valve (ViV) transcatheter aortic valve implantation is still an evolving method, we evaluated the development of early and midterm outcomes after ViV and conventional redo-surgical aortic valve replacement (SAVR) over the past 2 decades. In-hospital databases were retrospectively screened for patients ≥60 years treated for failing bioprosthetic aortic valves at our center. Clinical and follow-up characteristics were compared between patients who underwent ViV or redo-SAVR according to valve academic research consortium-2 (VARC-2) definitions. The comparison of outcome parameters was adjusted for baseline differences between groups. Between June 2002 and April 2020, 209 patients with ViV and 65 redo-SAVR patients met inclusion criteria. No significant differences were found in 30 days (ViV 3.8%, SAVR 3.1%, p = 0.778) or 6-month mortality (ViV 14.0%, SAVR 7.5%, p = 0.283). As patients with ViV less frequently experienced acute kidney injury (stage II or III) and life-threatening bleeding, they more frequently reached the 30-day VARC-2 combined safety end point (79.2% vs 61.5%, odds ratio [OR] 2.540, p = 0.023). Patients with ViV less frequently reached clinical efficacy (68.3% vs 84.6%, OR 0.408, p = 0.041) and device success (79.9% vs 92.3%, OR 0.311, p = 0.040) end points, because of higher frequency of postprocedural transvalvular gradients >20 mm Hg. However, over the past decade, VARC-2 clinical efficacy and device success rates continuously increased in ViV cases. In conclusion, ViV and SAVR were associated with similar acute mortality and different beneficial and adverse outcome profiles in this single-center cohort. Results after ViV procedures have continuously improved over the past years.

Meta-analysis Comparing Valve-In-Valve Transcatheter Aortic Valve Implantation With Self-Expanding Versus Balloon-Expandable Valves

Valve-in-valve (ViV) transcatheter aortic valve implantation (TAVI) is an alternative to redo-surgery in patients with failed surgical bioprostheses. It remains unclear whether outcomes vary when using either self-expanding (SE) or balloon-expandable (BE) valves. The aim of this study was to compare outcomes between SE and BE transcatheter heart valves when used for ViV TAVI. A systematic review of PubMed, MEDLINE, and EMBASE was performed identifying studies reporting outcomes following ViV TAVI. Event rates were pooled for meta-analysis using a random-effects model. The primary outcome was all-cause mortality at 12 months. Secondary outcomes included 30-day and 3-year mortality in addition to standard safety outcomes after the procedure as per the Valve Academic Research Consortium criteria. Nineteen studies reporting outcomes for 1,772 patients were included: 924 in the SE group and 848 patients in the BE group. There was no significant difference in all-cause mortality at 12 months (SE 10.3% vs BE 12.6%, p = 0.165, I² = 0%), or 3 years (SE 21.2% vs BE 31.2%, p = 0.407, I² = 63.79). SE valves had lower transvalvular gradients after procedure and acute kidney injury, but higher rates of pacemaker insertion, moderate or severe paravalvular regurgitation and need for ≥2 valves (all p < 0.05). There were no differences in stroke, coronary obstruction, bleeding, or vascular complications. Despite significant differences in key procedural outcomes between SE and BE valves when used for ViV TAVI, we found no difference in 12-month mortality. Tailored device selection may further reduce the risk of adverse procedural outcomes, particularly over the longer term.

Transcatheter aortic valve implantation: new hope in the management of valvular heart disease

Severe calcific aortic stenosis is relatively common, and unless treated with valve replacement it carries an adverse prognosis. A large number of patients, however, are denied surgery due to their advanced age or coexistent medical conditions that increase perioperative cardiovascular risks. Transcatheter aortic valve implantation (TAVI), a technique in which a bioprosthetic valve is inserted via a catheter and implanted within the diseased native aortic valve, is a new therapeutic modality for treatment of older patients with severe symptomatic aortic stenosis and other comorbidities, who have an inherently high surgical risk. This review will provide an overview of the pivotal trials in the development of TAVI; while also investigating important complications and limitations of the procedure and evaluating how new valves are being designed and clinically evaluated, with the ultimate goal of reducing potential complications and expanding the use of TAVI to lower-risk patient cohorts.

Transcatheter valve-in-valve implantation versus reoperative conventional aortic valve replacement: a systematic review

Transcatheter valve-in-valve (VIV) implantation for degenerated aortic bioprostheses has emerged as a promising alternative to redo conventional aortic valve replacement (cAVR). However there are concerns surrounding the efficacy and safety of VIV. This systematic review aims to compare the outcomes and safety of transcatheter VIV implantation with redoes cAVR. Six databases were systematically searched. A total of 18 relevant studies (823 patients) were included. Pooled analysis demonstrated VIV achieved significant improvements in mean gradient (38 mmHg preoperatively to 15.2 mmHg postoperatively, P<0.001) and peak gradient (59.2 to 23.2 mmHg, P=0.0003). These improvements were similar to the outcomes achieved by cAVR. The incidence of moderate paravalvular leaks (PVL) were significantly higher for VIV compared to cAVR (3.3% vs. 0.4%, P=0.022). In terms of morbidity, VIV had a significantly lower incidence of stroke and bleeding compared to redo cAVR (1.9% vs. 8.8%, P=0.002 & 6.9% vs. 9.1%, P=0.014, respectively). Perioperative mortality rates were similar for VIV (7.9%) and redo cAVR (6.1%, P=0.35). In conclusion, transcatheter VIV implantation achieves similar haemodynamic outcomes, with lower risk of strokes and bleeding but higher PVL rates compared to redo cAVR. Future randomized studies and prospective registries are essential to compare the effectiveness of transcatheter VIV with cAVR, and clarify the rates of PVLs.

New devices for TAVI: technologies and initial clinical experiences

Treatment of aortic stenosis in high-risk surgical patients has been modified in the past 10 years owing to the introduction of transcatheter aortic valve implantation (TAVI). Several issues affecting outcomes with implantation of the first-generation TAVI devices remain unresolved, including haemorrhagic and vascular complications, neurological events, rhythm disturbances, and paravalvular leakage. Further technological improvements are, therefore, required before the indications for TAVI can be extended to young and low-risk patients with aortic stenosis. Many new-generation TAVI devices are currently in the early stages of clinical evaluation. Modifications in the new devices include the ability to reposition the valve before final deployment, features to reduce paravalvular leakage, and the introduction of low-profile delivery systems. The aim of this Review is to provide an overview of the new-generation transcatheter valvular technologies, including initial clinical reports.