Conservative management without routine bailout stent for non-flow-limiting dissection after DCB angioplasty: a prospective three-arm study

The optimal management of non-flow-limiting coronary dissection after drug-coated balloon (DCB) angioplasty remains controversial, particularly in Asian populations. We conducted a prospective, three-arm cohort study to evaluate whether conservative management of non-flow-limiting dissection is non-inferior to bailout stent in patients with de novo medium-to-large coronary artery lesions. A total of 276 patients treated with DCB at Shaoxing Central Hospital were enrolled and divided into three Arms: conservative management for non-flow-limiting dissection (Arm 1, n = 91), bailout stent for dissection (Arm 2, n = 93), and none dissection (Arm 3, n = 82). The primary endpoint was 12-month major adverse cardiovascular events (MACE), including cardiac death, target vessel myocardial infarction, and clinically driven target lesion revascularization. Secondary endpoints included BARC 3–5 bleeding, all-cause death, recurrent angina, and ischemic stroke. At 12-month follow-up, the incidence of MACE was 7.7% (7/91) in the conservative management arm, 6.4% (6/93) in the bailout stent arm, and 5.4% (5/92) in the no-dissection control arm (Log-rank P > 0.05). The absolute risk difference (ARD) between conservative and bailout stent arms was 1.3% (95% CI: −4.2% to 6.8%). Since the upper 95% CI limit (6.8%) was below the prespecified 10% non-inferiority margin, non-inferiority was confirmed. The corresponding HR was 1.13 (95% CI: 0.58–2.19, P > 0.05). No significant between-group differences were observed in any secondary clinical endpoints (all P > 0.05). Multivariable Cox proportional-hazards regression analysis demonstrated that dissection management strategy was not an independent predictor of 12-month MACE (adjusted HR 1.12, 95% CI: 0.38–2.21, P > 0.05). Prespecified subgroup and sensitivity analyses yielded consistent results with no significant interaction effects (all P > 0.05). In conclusion, conservative management of non-flow-limiting NHLBI type A–C dissection after DCB angioplasty for de novo medium-to-large coronary lesions is non-inferior to bailout stenting for 12-month MACE in an Asian population, with clinical outcomes comparable to those of patients without dissection. Routine bailout stenting may be considered optional in this clinical setting. These findings suggest the potential value of conservative management as an alternative DCB-only strategy, within the pilot and exploratory nature of this study.