Coronary bifurcation stenting: selection of technique, side-branch protection, and prognostic relevant side-branch

To the Editor,

We read with great attention the case report titled ‘Intravascular ultrasound–guided tip-detection antegrade dissection and re-entry as a bailout strategy for calcification-induced side-branch occlusion during complex percutaneous coronary intervention: a case report’ by Kawai et al.¹ We applaud our colleagues for successfully managing a life-threatening complication that any interventional cardiologist would like to avoid if possible. However, we believe that some key points need to be addressed further discussion.

The stepwise provisional stenting (PS) is referred to as a simple approach; however, the procedure is sometimes not as simple, and side branch (SB) occlusion after main vessel (MV) stenting can occur in 6%–18% of cases.² Jailed wire technique (JWT) and jailed balloon technique (JBT) are the most commonly used strategies to preserve the SB during PS in patients with bifurcation lesions.² Jailed wire technique aims to use the guidewire’s body to keep a tract intact which would help to maintain perfusion to the SB, while JBT depends on a low profile balloon to work in the same manner. This concept is still a controversial issue, and most interventional cardiologist have used JWT to avoid SB occlusion; however, a previous trial indicated that the JBT is superior to the JWT in reducing SB occlusion.^3,4 We believe that JBT could be the ‘preferred technique’ especially in patients at high risk of plaque and carina shift.

Furthermore, since the diagonal branches vary in number, size, and distribution along the left anterior descending artery, they conceivably also vary in the amount of myocardium subserved by each. The Bifurcation Academic Research Consortium depicts a diagonal artery as a prognostically relevant SB if its SNuH (size, number, highest) score is ≥2, size >2.5 mm, and SB length >73 mm.⁵ In this case report, the second diagonal artery has a larger diameter, reaches the apex of the heart, and there is no other diagonal artery beneath it. Considering all these parameters, and as our colleagues have successfully demonstrated with intravascular ultrasound, the presence of an ipsilateral calcified lesion and the possible presence of a spiky carina due to the narrow angle, we believe that protecting the second diagonal artery with JWT or JBT in addition to the first diagonal artery might have been a more preferable approach.

Also, we would like to further discuss the choosing of the two-stent technique. The operator applied the intravascular imaging guided tip detection—antegrade dissection and re-entry, which we believe was the most challenging step in this case report, since the patient was also going through a periprocedural myocardial infarction and time was of the essence. After ensuring flow to the second diagonal artery, we believe the choice of technique might be one of the crush techniques (mini- double kissing-, or double barrel) instead of the culotte. Since calcium modifications, including rotational atherectomy, already caused major dissections in the MV, we believe a crush technique that allows the operator to keep the MV guidewire during the procedure (not requiring rewiring) would be a safer strategy because it might have decreased the possibility of subintimal wiring.

In conclusion, the SNuH score might be kept in mind while determining the prognostic value of diagonal arteries. Additionally, crush techniques can be an option, especially if a major dissection has occurred in the MV, as they allow the operator to keep the MV-wire during the procedure.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Data availability

No new data were generated or analysed in support of this research.