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Khokhar et al. Mini-invasive Surg 2022;6:2 https://dx.doi.org/10.20517/2574-1225.2021.97 Page 5 of 19

immediately with subsequent median sternotomy for surgical exploration and repair. Use of extracorporeal
membrane oxygenation (ECMO) is not helpful and may delay definite surgical management.

In exceptional cases, due to the extreme surgical risk of these patients, percutaneous bail-out measures have
been described. The annular tear can be sealed using vascular plugs, embolization coils, implantation of a
vascular occlusion device in cases of muscular ventricular septal defect perforations, and less successfully
implantation of a second transcatheter heart valve (THV) [39-41,42] . In our experience, reversal of heparin can
be resolutive when extravasation is limited. For more limited or contained ruptures, a conservative
approach can be considered with reversal of heparin, prompt pericardial drainage, and close repeated
echocardiographic or MSCT surveillance . Echocardiography is also useful to detect subtle signs of aortic
[43]
injury such as presence of effusion in the transverse sinus, subepicardial hematoma at the base of the heart,
peri-aortic hematoma, new aortic wall thickening, and local or extended aortic dissection [32,44] .

AORTIC AND VENTRICULAR
Iatrogenic aortic dissection is more common in heavily diseased, calcified, and tortuous aortic anatomies .
[45]
Care should be taken during device and sheath manipulation in these aortas with wire and catheter
exchanges minimized. In a tortuous or horizontal aorta, an additional stiff wire advanced into the aortic
root can enhance the support and deliverability of the THV. In cases of extremely hostile aortas, trans-apical
TAVR can be considered as an alternative access route.

Improvements in device technology and operator experience has reduced the incidence of cardiac
tamponade down to around 1% . Right ventricular perforation is more common and can occur due to
[46]
placement of the temporary pacing wire. Use of a balloon-tipped pacing wire or pacing via the LV guidewire
[47]
can therefore lower this risk . Isolated right ventricular perforation rarely requires surgery and usually
conservative management with pericardiocentesis is sufficient. In contrast, LV perforation almost always
requires prompt surgical repair. The use of softer pre-shaped LV guiding wires has reduced the incidence of
this complication.

TRANSCATHETER VALVE EMBOLIZATION
Transcatheter valve embolization (TVE) is defined as movement of valve prosthesis after deployment such
that it loses contact with the annulus. It has a reported incidence of around 1% and is associated with
elevated post-procedural morbidity and mortality and need for conversion to open heart surgery [48-51] . TVE
can occur in the aortic or ventricular direction and usually occurs during the peri-procedural period,
however delayed migration (> 24 h post-procedure) has been reported [49,52,53] .

Minimizing risk of transcatheter valve embolization
[49]
Multiple anatomical, procedural, and THV risk factors for TVE have been identified . On pre-procedural
MSCT, attention should be given to the presence of significant aortic tortuosity, excessively small or large
annuli, complete absence or presence of heavy calcification, and LVOT hypertrophy [Figure 1]. Pure aortic
regurgitation is usually associated with the combination of large annuli, absence of significant calcification
for device anchoring, and larger stroke volume, all of which can increase the risk for TVE. To mitigate this
risk, device over-sizing and rapid ventricular pacing during deployment is recommended. Additionally,
dedicated THV such as the Jena valve (Jena Valve Technologies, Irvine CA) or J-valve (JC Medical,
Burlingame, CA) can be considered. When treating bicuspid aortic valve stenosis with heavy calcification, a
THV with increased radial strength should be selected to avoid device under-expansion and subsequent risk
of TVE.