Single-Center Experience With the LOTUS Edge Transcatheter Heart Valve

Transcatheter Aortic Valve Implantation: Addressing the Subsequent Risk of Permanent Pacemaker Implantation

Transcatheter aortic valve implantation (TAVI) is now a commonly used therapy in patients with severe aortic stenosis, even in those patients at low surgical risk. The indications for TAVI have broadened as the therapy has proven to be safe and effective. Most challenges associated with TAVI after its initial introduction have been impressively reduced; however, the possible need for post-TAVI permanent pacemaker implantation (PPI) secondary to conduction disturbances continues to be on the radar. Conduction abnormalities post-TAVI are always of concern given that the aortic valve lies in close proximity to critical components of the cardiac conduction system. This review will present a summary of noteworthy pre-and post-procedural conduction blocks, the best use of telemetry and ambulatory device monitoring to avoid unnecessary PPI or to recognize the need for late PPI due to delayed high-grade conduction blocks, predictors to identify those patients at greatest risk of requiring PPI, important CT measurements and considerations to optimize TAVI planning, and the utility of the MInimizing Depth According to the membranous Septum (MIDAS) technique and the cusp-overlap technique. It is stressed that careful membranous septal (MS) length measurement by MDCT during pre-TAVI planning is necessary to establish the optimal implantation depth before the procedure to reduce the risk of compression of the MS and consequent damage to the cardiac conduction system.

Incidence and mechanisms of bioprosthetic dysfunction after transcatheter implantation of a mechanically-expandable heart valve

BACKGROUND

The mechanically-expandable transcatheter valve is no longer commercially available, yet clinical and echocardiographic surveillance is imperative for thousands of patients who received transcatheter aortic valve implantation (TAVI) with this platform.

AIMS

We aimed to determine the incidence and mechanism of bioprosthetic valve dysfunction (BVD) following TAVI with mechanically-expandable valves.

METHODS

From 2013 to 2020, all 234 patients who underwent TAVI with the LOTUS valve were included. BVD was categorised as (i) structural valve deterioration (SVD), (ii) non-structural valve dysfunction (NSVD), (iii) clinical valve thrombosis and (iv) endocarditis, according to the Valve Academic Research Consortium-3 criteria.

RESULTS

The mean age was 79±7 years, 60% were male, and the mean Society of Thoracic Surgeons score was 4.2±2.9%. The technical success rate was 94% and the 30-day device success rate was 78%. All-cause mortality at 1 year was 15%; median follow-up duration was 36 (IQR 18-60) months during which 47% of patients died. One hundred and three patients had ≥1 type of BVD (44%), which predominantly consisted of NSVD (39%, mostly because of ≥moderate patient-prosthesis mismatch). BVD during follow-up included endocarditis (3.4%), clinical valve thrombosis (3.4%) and SVD (1.3%). Both endocarditis and clinically apparent valve thrombosis occurred early and late after TAVI and resulted in valve-related deaths in 38% and 13% of patients, respectively. Overall, ≥moderate haemodynamic valve deterioration occurred in 5.5% and bioprosthetic failure in 7.3%, leading to valve-related deaths in 36% of cases.

CONCLUSIONS

BVD represents a relevant health issue after TAVI with a mechanically-expandable valve. Serious but reversible causes of BVD include endocarditis and clinically apparent valve thrombosis, both carrying a time-independent hazard post-TAVI.

Impact of left ventricular outflow tract calcium on valve geometry in self-expanding transcatheter aortic-valve replacement

OBJECTIVES

Evaluate transcatheter heart valve (THV) geometry according to left ventricular outflow tract (LVOT) calcium degree and its impact on hemodynamics and outcomes in patients undergoing transcatheter aortic valve replacement (TAVR) with a contemporary self-expanding THV.

BACKGROUND

LVOT calcium remains challenging for contemporary THVs. LVOT calcium location and degree may affect THV deployment and impact flow patterns and shear stress, accelerating THV degeneration.

METHODS

EPROMPT (CoreValve Evolut Pro Prospective Registry; NCT03423459) is a prospective, investigator-initiated, multicenter registry of patients undergoing TAVR using CoreValve Evolut PRO/PRO + THVs. A total of 107 patients were enrolled in EPROMPT's computed tomography (CT) cohort between January 2018 and October 2021. These patients underwent follow-up CT scan 30 days post-TAVR. We analyzed THV geometry and its interaction with the aortic root following deployment using 30-day post-TAVR CT in patients with none/mild versus moderate/severe LVOT calcium.

RESULTS

Thirty-day THV inflows were less eccentric in the short axis in patients with none/mild versus moderate/severe LVOT calcium (1.16 ± 0.09 vs. 1.21 ± 0.12; p = 0.007). THV became more circular and was similar between both cohorts at the THV waist (1.08 ± 0.06 vs. 1.09 ± 0.11; p = 0.551), leaflet tips (1.03 ± 0.04 vs. 1.05 ± 0.09; p = 0.299), and THV outflow (1.04 ± 2.2 vs. 1.03 ± 2.7; p = 0.143). Thirty-day > mild paravalvular leak was low in both cohorts (1.5% vs. 2.4%; p = 0.724); mean gradients were similar (7.7 ± 3.6 vs. 7.7 ± 3.4 mmHg; p = 0.955).

CONCLUSIONS

Despite inflow deformities observed in patients with moderate/severe LVOT calcium, Evolut PRO/PRO + conforms to elliptical aortic annuli, maintaining circularity and proper function at the leaflets and outflow, even in patients with moderate/severe LVOT calcium.