Background:
Self-expandable prostheses for transcatheter aortic valve replacement (TAVR) frequently require permanent pacemaker implantation (PPI).
Methods:
148 consecutive patients implanted with the novel Navitor TAVR system were compared to 181 consecutive patients implanted with the Evolut system. Patients with preexisting PPI, high-risk ECG (right-bundle branch block) and Navitor 35mm/Evolut 34mm implantation were excluded.
Results:
Patients treated with the Navitor system were elderly (83.0 {78-86} vs. 81.0 {76.0-84.0} years, p<0.01) and had higher interventional risk according to the STS score for mortality (5.6 {3.0-9.9} vs. 4.3 {2.5-7.0} %, p=0.04). 17.6% of Navitor compared to only 6.7% of Evolut patients required PPI (p<0.01).
Those Navitor patients requiring PPI had larger aortic annuli (annular area: 481.0±45.5 vs. 444.0±76.4mm2, p=0.02) and increasing PPI risk was observed with prosthesis size (OR: 1.52; 95% CI: 1.1-2.0, p=0.01). Prosthesis oversizing was similar in both groups (3.2±4.4 vs. 3.3±2.9%, p=0.91), while preexisting left-bundle branch block (23.1 vs. 10.7, p=0.1) tended to be more frequent in PPI patients.
Final implantation depth was significantly deeper in Navitor patients requiring PPI (5.3±1.8 vs. 4.3±2.2mm, p=0.04). High implantation of the Navitor valve using a start position ≤3mm within the annular plane was associated with a significantly lower rate of PPI (2.9 vs. 30.8%, p<0.01).
Conclusion:
Among self-expandable valves, higher PPI rates were observed with the Navitor compared to the Evolut TAVR system. Implantation depth of the Navitor valve could be a modifiable target to reduce PPI rates, but may increase risk for valve migration.
