Valve-in-Valve Challenges: How to Avoid Coronary Obstruction

Abstract

Coronary obstruction is a rare but life-threatening complication in patients undergoing transcatheter aortic valve replacement (TAVR). Aortic valve-in-valve (VIV) procedures to treat failed surgical bioprosthesis is associated with ~6-fold higher risk for coronary obstruction in certain situations. The primary mechanism consists in the occlusion of the coronary ostium by the dislodged leaflet from the bioprosthesis after deployment of the transcatheter heart valve (THV), which most commonly occurs during the index procedure, but in up to 1/3 of cases a delayed presentation ensues. The clinical presentation consists of severe hypotension and ECG changes in most of the patients, with very high mortality rates. Therefore, pre-procedural multi-slice computed tomography is crucial for identifying high-risk features, such as low coronary heights, shallow sinuses of Valsalva, and short virtual THV to coronary ostial distance (VTC). Also, some models of surgical bioprosthesis present an increased risk for this dreadful complication. Preemptive protective strategies with coronary wiring, with or without placement of an undeployed stent, could mitigate the risks associated with this complication in high-risk patients, even though studies are lacking. This review aims to take a clinical perspective on the challenges in avoiding this complication during VIV procedures.

Keywords: coronary obstruction; failed surgical bioprosthesis; transcatheter aortic valve replacement; transcatheter heart valve; valve-in-valve.

Figure 1

(A) Incidence of coronary obstruction in the main studies in the context of valve-in-valve; (B) Incidence of coronary obstruction according to the type of surgical bioprosthesis. Adapted from Ribeiro et al. (10). Copyrights (2017), with permission from Oxford University Press (license number: 4586671024004).

Figure 2

Main surgical bioprosthesis related with an increased risk of coronary obstruction.

Figure 3

MSCT evaluation of a TAVR VIV case with high-risk features for coronary obstruction. (A) Left coronary height to the valve plane of 6.6 mm; (B) Right coronary height to the valve plane of 9.5 mm; (C) Low STJ; (D) Measurement of the SHV internal diameter; (E) Measurement of the SOV diameters; (F) Measurement of the STJ diameters; (G) Identification of SHV (Medtronic Hancock Standard); (H,I) VTC value <4.0 mm for both left and right coronary arteries.

Figure 4

Suggested pre-procedural risk assessment algorithm for coronary obstruction in patients undergoing VIV.

Figure 5

Example of a left coronary artery chimney stenting technique in a high-risk for coronary obstruction patient receiving a Sapien XT valve with a preemptive guidewire protection approach.

Figure 6

BASILICA procedure. (A) A catheter directs an electrified guidewire through the base of the left aortic cusp into a snare in the left ventricular outflow tract; (B) After snare retrieval; (C) The mid-shaft of the guidewire is electrified to lacerate the leaflet; (D) The leaflet splays after transcatheter aortic valve replacement permitting coronary flow. Reprinted from Khan et al. (19). Copyrights (2018), with permission from Elsevier (license number: 4587251472719).