NoTrace-CTO: Exclusive Drug-Coated Balloon Use After Recanalization of Chronic Total Coronary Occlusions - A Prospective, Single-Center, Single-Arm Study With Paired Quantitative Coronary Angiography and Serial Intravascular Ultrasound
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 38
- 试验地点
- 1
- 主要终点
- In-balloon late lumen loss at nine months
研究概览
简要总结
Chronic total occlusions (CTO) of the coronary arteries are usually treated with drug-eluting stents (DES) after successful recanalization. Permanent metallic scaffolds carry recognized long-term limitations, including late malapposition, very late stent thrombosis, impairment of positive vascular remodeling, and edge restenosis after geographic miss. Drug-coated balloons (DCB) deliver an antiproliferative agent to the vessel wall without leaving a permanent implant, and may be particularly attractive in long, fibrocalcific recanalized CTO segments.
NoTrace-CTO is a prospective, single-center, investigator-initiated, single-arm pilot study evaluating an exclusive DCB-only strategy, with no stent implantation, after successful CTO recanalization. Thirty-eight patients are planned, to yield thirty evaluable patients with paired angiographic follow-up.
The primary endpoint is in-balloon late lumen loss at nine months, measured by quantitative coronary angiography (QCA) and tested against a pre-specified performance goal of 0.50 mm derived from a pooled contemporary second-generation DES benchmark. The proportion of lesions completing the DCB-only strategy without bailout stenting is reported descriptively alongside it. Serial intravascular ultrasound (IVUS) performed at baseline, immediately after DCB delivery and at nine months is the mechanistic centerpiece of the study, assessing vascular remodeling directly. Secondary assessments include quantitative flow ratio (QFR), Seattle Angina Questionnaire (SAQ) scores, binary restenosis, reocclusion, target lesion and target vessel revascularization, major adverse cardiovascular events (MACE), bleeding classified by the Bleeding Academic Research Consortium (BARC) criteria, and acute kidney injury defined by the Kidney Disease: Improving Global Outcomes (KDIGO) criteria.
The study is not powered for comparative clinical superiority or non-inferiority against DES; its findings are hypothesis-generating and intended to inform the design of an adequately powered multicenter trial.
详细描述
Design:
Prospective, single-center, investigator-initiated, single-arm pilot study conducted at the Heart Institute (InCor), Hospital das Clinicas, University of Sao Paulo Medical School. Consecutive eligible patients are enrolled by convenience sampling from the institutional chronic total occlusion (CTO) recanalization waiting list, following routine care pathways without modification of clinical prioritization or therapeutic decision-making.
Index procedure:
Recanalization follows standard interventional practice under the hybrid CTO algorithm, including antegrade wire escalation, antegrade dissection and re-entry, and retrograde approaches. Baseline lesion complexity is graded with the Multicenter CTO Registry of Japan (J-CTO) and Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO) scores. Lesion preparation uses sequential semi-compliant and non-compliant balloon predilatation sized approximately 1:1 to the intravascular ultrasound (IVUS) measured reference lumen diameter; cutting or scoring balloons are used at operator discretion where fibrocalcific tissue prevents adequate luminal gain. Drug-coated balloon (DCB) delivery proceeds only after angiographic and IVUS confirmation of adequate lesion preparation, defined as absence of flow-limiting or otherwise significant dissection, and satisfactory conditions for drug delivery.
Device and technique:
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age 18 years or older
- •Chronic total coronary occlusion (CTO) of more than three months' duration, confirmed by prior angiography or lesion characteristics
- •Clinical indication for revascularization, defined as limiting angina and/or documented ischemia
- •Successful CTO recanalization, defined as restoration of Thrombolysis in Myocardial Infarction (TIMI) grade 3 antegrade flow and absence of any flow-limiting dissection
- •Life expectancy greater than one year
- •Written informed consent provided
排除标准
- •Acute coronary syndrome or cardiogenic shock at presentation
- •Flow-limiting dissection (TIMI grade below 3) requiring stent implantation
- •Left main coronary artery as the CTO target vessel
- •Reference vessel diameter below 2.0 mm or above 4.0 mm
- •In-stent chronic total occlusion
- •Absolute contraindication to dual antiplatelet therapy for the protocol-defined duration of 3 to 6 months
- •Inability to achieve adequate lesion preparation, defined as absence of flow-limiting or otherwise significant dissection and satisfactory conditions for drug delivery, confirmed by angiography and intravascular ultrasound (IVUS)
研究组 & 干预措施
DCB-only strategy
Patients with successful chronic total occlusion (CTO) recanalization and adequate lesion preparation, confirmed by intravascular ultrasound (IVUS) and angiography, receive exclusive paclitaxel drug-coated balloon (DCB) treatment of the target lesion, with no permanent metallic scaffold implanted. Bailout stent implantation is performed only for flow-limiting dissection that cannot be optimized with repeat balloon inflation, and is classified as technical failure of the DCB-only strategy.
干预措施: Paclitaxel-coated balloon (AGENT Paclitaxel-Coated PTCA Balloon Catheter) (Device)
DCB-only strategy
Patients with successful chronic total occlusion (CTO) recanalization and adequate lesion preparation, confirmed by intravascular ultrasound (IVUS) and angiography, receive exclusive paclitaxel drug-coated balloon (DCB) treatment of the target lesion, with no permanent metallic scaffold implanted. Bailout stent implantation is performed only for flow-limiting dissection that cannot be optimized with repeat balloon inflation, and is classified as technical failure of the DCB-only strategy.
干预措施: Serial intravascular ultrasound and protocol-mandated nine-month angiographic reassessment (Procedure)
结局指标
主要结局
In-balloon late lumen loss at nine months
时间窗: 9 months
Difference between the minimal luminal diameter measured by quantitative coronary angiography immediately after the index procedure and the minimal luminal diameter at nine-month follow-up angiography. This is the sole endpoint against which the pre-specified performance goal of 0.50 mm is formally tested, using the upper bound of the one-sided 97.5% confidence interval, in the per-protocol population.
DCB-only strategy success
时间窗: Periprocedural
Proportion of enrolled, successfully recanalized lesions treated exclusively with a drug-coated balloon without bailout stent implantation, defined consistent with Drug-Coated Balloon Academic Research Consortium recommendations and calculated on the full intention-to-treat denominator. Reported descriptively with an exact Clopper-Pearson 95% confidence interval; not hypothesis-tested against a performance goal.
次要结局
- In-segment late lumen loss at nine months(9 months)
- Change in quantitative flow ratio(Periprocedural and 9 months)
- In-balloon binary angiographic restenosis at 9 months(9 months)
- In-segment binary angiographic restenosis at 9 months(9 months)
- Target lesion reocclusion(9 months)
- Clinically driven target lesion revascularization(9 months)
- Clinically driven target vessel revascularization(9 months)
- Change in minimal lumen area by intravascular ultrasound(Periprocedural and 9 months)
- Change in external elastic membrane cross-sectional area by intravascular ultrasound(Periprocedural and 9 months)
- Vascular remodeling index by intravascular ultrasound(Periprocedural and 9 months.)
- Change in plaque burden by intravascular ultrasound(Periprocedural and 9 months)
- Change in percent atheroma volume by intravascular ultrasound(Periprocedural and 9 months)
- Change in Seattle Angina Questionnaire Physical Limitation domain score(Baseline, 1 month, and 9 months)
- Change in Seattle Angina Questionnaire Angina Stability domain score(Baseline, 1 month, and 9 months)
- Change in Seattle Angina Questionnaire Angina Frequency domain score(Baseline, 1 month, and 9 months)
- Change in Seattle Angina Questionnaire Treatment Satisfaction domain score(Baseline, 1 month, and 9 months)
- Change in Seattle Angina Questionnaire Angina-Related Quality of Life domain score(Baseline, 1 month, and 9 months)
- Number of participants with major adverse cardiovascular events(Up to 9 months)
- Number of participants with bleeding events by Bleeding Academic Research Consortium type(Up to 9 months)
- Number of participants with acute kidney injury(Periprocedural)