Subintimal bailout recanalization for acute stent-jailed side branch occlusion: a single-center retrospective case series with QFR assessment

BACKGROUND: Acute side branch (SB) occlusion after main vessel (MV) stenting remains a challenging complication of bifurcation PCI, particularly when conventional true-lumen rewiring attempts fail. In such scenarios, operators face limited standardized bailout options, and guidance on decision-making is scarce. METHODS: We retrospectively analyzed a highly selected single-center case series of patients with acute stent-jailed SB occlusion refractory to conventional rewiring who underwent chronic total occlusion (CTO)-derived subintimal bailout recanalization. A predefined technical framework was applied. Angiographic results were assessed using Thrombolysis in Myocardial Infarction(TIMI) flow, and angiography-derived quantitative flow ratio (QFR) was used as physiological confirmation of reperfusion. RESULTS: Among 9,832 PCI procedures performed between 2019 and 2023, 15 consecutive patients met the inclusion criteria. Subintimal SB recanalization was achieved in all cases, resulting in restoration of TIMI 3 flow. Postprocedural SB QFR was successfully obtained in all patients, with a mean value of 0.91 ± 0.04; all exceeded the predefined ischemic threshold (QFR ≥ 0.80). No procedure-related perforation, tamponade, or device entrapment was observed. Limited follow-up angiography and QFR data, available in two patients, demonstrated stable or improved functional values. CONCLUSIONS: In a highly selected case series managed at an experienced center, a structured subintimal bailout framework appears feasible for the treatment of acute stent-jailed SB occlusion when conventional rewiring fails. Integration of QFR provides objective physiological confirmation of SB reperfusion and may assist in procedural decision-making. These findings should be considered hypothesis-generating and warrant validation in larger, prospective studies.