Background: The feasibility and long-term outcomes of the
CrossBoss/Stingray for treating coronary chronic total occlusions (CTO) with
distal diffuse disease landing zone remain unclear. Methods: Consecutive
CTO patients with distal diffuse lesions that underwent percutaneous coronary
intervention by the CrossBoss/Stingray system at Xijing Hospital from April 2016
to October 2020, were included. Patients were analyzed by two groups according to
the extent of stenosis in the distal landing zone:
50%–70% stenosis (moderate stenosis group)
and 70% stenosis (severe stenosis group). The primary efficacy outcome was
technical success, defined as the frequency
of true lumen guidewire placement distal to the CTO. The composite endpoint of
all-cause death, any stroke, or any revascularization was also explored.
Results: A total of 91 consecutive patients were included, with 32
patients in the moderate stenosis group and 59 patients in the severe stenosis
group. The mean J-CTO score was 2.5 1.1. The technical success rate was
79.1% (72/91) in the overall population and was similar between the 2 groups:
78.1% (25/32) and 79.7% (47/59) (p = 0.608). No coronary perforation
occurred. With a median follow-up of 29 months (IQR: 53–92), the estimated rate
of the composite endpoint of all-cause death, any stroke, or any
revascularization was 50.4% (all-cause death: 16.6%, any stroke: 1.1%, any
revascularization: 36.5%) in the overall population. No significant difference
was observed in the rate of the composite endpoint between the moderate stenosis
group and the severe stenosis group (45.1% vs. 54.3%, respectively,
p = 0.797). Conclusions: In CTO lesions with distal diffuse
disease landing zone, the technical success rates of CrossBoss/Stingray and the
long-term clinical outcomes were not significantly different between the moderate
stenosis group (50%–70%) and the severe stenosis group (70%). However, the
relatively high rate of long-term clinical outcomes, especially any
revascularization, warrants further investigations on this indication in future
studies.