The question as to whether one or two DES should be used cannot be answered on the basis of this study. The study showed a low rate (less than 6%) of main branch restenosis with the Cypher stent (regardless of the strategy) and an acceptable rate of side branch restenosis (22% in the two stents group compared with 14% in the balloon + stent group, p=not significant). To date, the reason for the excess of restenosis in the side branch has not been elucidated, though possible explanations may include geographical miss, lack of stent apposition at the carina and role of the technical approach.

In a more recent retrospective study, Ge et al., compared two treatment types with sirolimuseluting stents in 174 consecutive patients with bifurcation lesions (stenting only one branch in 57 or stenting both branches in 117). They found the same trend with DES (see Figure 5) as observed with BMS (see Figure 2) in favour of using one stent (incidence of target vessel revascularisation 5.4% compared with 11.1%, p=0.51 and cumulative MACE (18.9% compared with 23.3%, p=0.76) at nine months.

Figure 5: One or Two Drug-eluting Stents in Bifurcation Lesions

With the advent of DES, new techniques such as Crush or simultaneous kissing stent have been proposed in order to simplify the technical approach and reduce the risk of side branch restenosis. Recent data presented during the American College of Cardiology (ACC) scientific sessions did not demonstrate any benefit associated with these techniques. An excess of restenosis was even evidenced in the absence of final kissing (see Figure 6) as well as an increased risk of stent thrombosis (see Figure 7).

Figure 6: Crushing Technique – Kissing or not Kissing

Conclusions

Coronary bifurcation disease is frequent and can be adequately treated using an appropriate stenting strategy. The advent of DES has generated lengthy debates and a consensus has been reached as to a rational and safe approach applicable in more than 70% of cases. In cases where there is no lesion in the side branch or a purely ostial lesion, stenting the main branch with a jailed wire in the side branch followed by provisional T-stenting of the side branch after guide wire exchange appears to be the most rational and successful strategy, provided that final kissingballoon inflations are systematically performed.

Figure 7: Drug-eluting Stents in Bifurcation Lesions – Safety Data

In the presence of more complex lesions, namely when the side branch lesion extends beyond the ostium by more than 2 or 3mm, a second stent is required in the majority of cases. In such cases, the most appropriate technique between the Crush, simultaneous kissing stent or T-stenting techniques is still the subject of much debate. The data generated by the bench studies and preliminary clinical studies seem to favour the T-stenting technique starting with the main branch.

New dedicated DES and delivery systems will be available in the near future. These new devices will undoubtedly simplify the technical approach and possibly solve the problem of side branch restenosis.