Page 31 - Read Online

Khokhar et al. Mini-invasive Surg 2022;6:2 https://dx.doi.org/10.20517/2574-1225.2021.97 Page 13 of 19

During the procedure, rapid atrial pacing can be performed to risk stratify patients. Those who develop
atrial-pacing-induced Wenckebach atrioventricular (AV) block are at high risk for PPI, especially when AV
block occurs at lower rates of atrial pacing. Among 284 patients who were evaluated, those who did not
[134]
develop Wenckebach AV block had a negative predictive value of 98.7% for PPI .

Choice of valve prosthesis can have an impact, with lower rates of PPI seen with the use of BEV compared
[128]
to SEV . Latest generation valves such as the ACURATE neo, with its low radial strength, were associated
with a low PPI rate of 8.3% in a 1000 patients . Furthermore, procedural techniques have been developed
[135]
which aim to precisely and systematically achieve a higher implantation with the aim of further reducing
permanent pacemaker implantation rates. The cusp overlap technique involves overlapping the left and
[136]
right coronary cusps to isolate the non-coronary cusp . This is achieved by rotating the C-arm in a right
anterior oblique caudal direction and the optimal projection can be determined from pre-procedural CT.
The key advantage of this projection is that both the delivery catheter and aortic cusps can be aligned,
delivery catheter parallax is eliminated, and the LVOT is not foreshortened, which allows for a more precise
and higher implantation depth. Early registry data are promising with dramatically lower permanent
pacemaker (PPM) implantation rates (4%-7%) observed when using the cusp overlap technique with
different THV [137,138] . Further lowering of PPM rates, particularly with self-expandable devices, can be
[139]
achieved using the minimizing depth according to the membranous septum technique . This patient-
specific approach utilizes the pre-procedural CT to measure the membranous septum, aiming to achieve an
implantation depth less than the length of the membranous septum. When this technique was applied to a
consecutive series of patients prospectively, pacemaker implantation rates fell from 9.7% to 3% with rates of
left bundle branch block falling from 25.8% to 9% .
[139]

At the end of the procedure, consideration must be given to the duration and type of monitoring
required . An algorithmic approach to select which patients require prolonged hospital or ambulatory
[129]
ECG monitoring may minimize the potentially fatal complication of post-discharge high-grade atrio-
ventricular block [129,140] .

CONCLUSION
The evolution of device technology and operator experience has dramatically changed the safety profile of
TAVR. However, the need to prevent and appropriately manage peri-procedural complications remains
ever important, especially as TAVR expands towards lower surgical risk populations. Meticulous pre-
procedural planning is critical to ensuring the risk for complications is minimized.

DECLARATIONS
Authors’ contributions
Conception and design of review article: Khokhar AA, Giannini F, Dudek D, Colombo A
Writing of content and creation of figures: Khokhar AA, Ruggiero R, Chandra K, D’Agostino A, Toselli M,
Mangieri A, Colombo A
Critical review of article: Khokhar AA, Toselli M, Mangieri A, Dudek D, Colombo A, Giannini F

Availability of data and materials
Not applicable.

Financial support and sponsorship
None.