The Mirage of the Optimal Implantation Depth With Transcatheter Bioprosthesis

Predictors of pacemaker implantation after TAVI in a registry including self, balloon and mechanical expandable valves

The need for permanent pacemaker implantation (PPMI) is a burdensome complication of transcatheter aortic valve implantation (TAVI). The aim of our study was to evaluate different anatomical, clinical, electrocardiographic, and procedural variables associated with the development of conduction abnormalities after TAVI across the entire device spectrum. Single-center prospective cohort of consecutive patients who underwent TAVI since March 2017. Final cohort was studied to detect areas of calcium within aortic valve characterized by leaflet sector and region. Membranous septum (MS) length was assessed throughout a modified coronal view. Device selection and positioning were performed according to the operator criteria. Device selection and positioning were performed according to the operator criteria. From the 273 patients included, 57 underwent PPMI (20.8%). Univariate analysis determined right bundle branch block (RBBB), QRS duration, MS length and calcium within LVOT of non-coronary cuspid as independent predictors. After multivariable logistic regression, both RBBB (OR 6.138; 95% CI 1.23-30.73, P = 0.027) and MS length (OR 0.259; 95% CI 0.164-0.399, P < 0.005) emerged as statistically significant. As a model, they could predict PPMI in 88.7%, independently of which valve used. Youden index analysis yielded 7.69 mm as the optimal cut-off with a negative and positive predictive value of 94.7 and 71.9%, respectively. In our experience, both RBBB pattern and short membranous septum (< 8 mm) were strongly and independently associated with new permanent pacemaker implantation, regardless of the device type. Our findings suggest that this simple evolved measure of MS length may guide device selection and implantation technique and facilitate early discharge.

Evolut Self-Expanding Transcatheter Aortic Valve Replacement in Patients with Extremely Horizontal Aorta (Aortic Root Angle ≥ 70°)

Because of its rigidity and non-steerability, the presence of a horizontal aortic root poses a major anatomical issue during transcatheter aortic valve replacement (TAVR) with Evolut self-expanding valve. Previous studies have elucidated the difficulties of coaxial implantation of the self-expanding valve in patients with horizontal aorta, often resulting in increased complications and a lower device success rate. To date, most patients with extremely horizontal aorta (aortic root angle ≥ 70°) have been excluded from major TAVR clinical trials. Therefore, available data on TAVR with Evolut in this challenging anatomy are limited, and standardized treatment strategies and clinical results remain unknown. Herein, we report a clinical case series of TAVR with Evolut in extremely horizontal aorta. Among seven patients (aged 80-92 years; STS score, 12.6% ± 7.9%) who underwent TAVR with Evolut system, aortic root angle ranged from 71° to 83° (mean, 75.1°± 4.5°). All patients achieved device success with dedicated strategies and were clinically stable at 3-month follow-up. None of the patients had more than mild paravalvular leakage (PVL) at any point during follow-up.Complications in three patients included complete atrioventricular block requiring a permanent pacemaker implantation, cerebral infarction because of atrial fibrillation 3 days after TAVR, and cardiac tamponade requiring pericardiocentesis. In this case series, Evolut self-expanding TAVR in extremely horizontal aorta was effective and feasible with a high device success rate. Based on anatomical features, some dedicated strategies majorly contribute to the success of this procedure. Large-scale multicenter studies are required to confirm our findings.