Composite Outcomes in Percutaneous Coronary Interventions with the Dedicated Bifurcating Tryton Side Branch Stent - A Systematic Review

Background
Bifurcation lesions account for 15-20% of all percutaneous coronary interventions (PCI) and are associated with increased adverse cardiac events compared with non-bifurcation lesions. Dedicated bifurcation stents, such as the Tryton side branch stent have been developed with the aim of improving clinical outcomes. We performed a systematic review to evaluate the role of bifurcating side branch stenting on long term clinical outcomes and angiographic findings.

Methods
A systematic literature search was performed in PubMed, EMBASE, US National Institutes of Health Registry of Clinical Trials, the Cochrane Central Register of Controlled Trials, Web of Science, Scopus, Ovid, Google Scholar and meeting abstracts for clinical trials evaluating the use of dedicated Tryton bifurcation stents. Angiographic and composite clinical outcomes including Major adverse clinical and cardiac events (MACCE) were compared with descriptive statistics.

Results
A total of 14 studies (n=1722) were included in the systematic review. Average follow-up was 12.9 ±10 months. Mean age of the patients was 66±1.2 years and there were 73.7±8.1% male. Procedural success was 94.7±5.3%, technical success 97.4±1.7%. Use of dedicated Tryton bifurcating stent was associated with a MACCE rate of 8.7±3.6%, target vessel failure (TVF) 9.4±7.0%, periprocedural MI 5.2±4.4%, stent thrombosis 1.2±1.3%, clinically driven target lesion revascularization 5.0±2.4%, and cardiac death of 1.8±1.4%. There has been only one randomized clinical trial comparing Tryton and provisional bifurcation PCI which showed TVF of 17.4%, periprocedural MI 13.6%, stent thrombosis 0.3%, and cardiac death of 1.2%. When bifurcations with branches <2.25 mm were excluded in the randomized trial, the TVF rate decreased to 11.3%, meeting non-inferiority criteria

Conclusions
This systematic review summarizes all available clinical data on the Tryton bifurcation stent. Based on our descriptive analysis, the Tryton bifurcation stent provides a safe and effective alternative to provisional stenting, likely in lesions ³ 2.25 mm. Further research comparing the Tryton stent with other bifurcation techniques is warranted